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Sample records for situ stabilization technique

  1. In situ containment and stabilization of buried waste

    Energy Technology Data Exchange (ETDEWEB)

    Allan, M.L.; Kukacka, L.E.; Heiser, J.H.

    1992-11-01

    The objective of the project was to develop, demonstrate and implement advanced grouting materials for the in-situ installation of impermeable, durable subsurface barriers and caps around waste sites and for the in-situ stabilization of contaminated soils. Specifically, the work was aimed at remediation of the Chemical Waste (CWL) and Mixed Waste Landfills (MWL) at Sandia National Laboratories (SNL) as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). This report documents this project, which was conducted in two subtasks. These were (1) Capping and Barrier Grouts, and (2) In-situ Stabilization of Contaminated Soils. Subtask 1 examined materials and placement methods for in-situ containment of contaminated sites by subsurface barriers and surface caps. In Subtask 2 materials and techniques were evaluated for in-situ chemical stabilization of chromium in soil.

  2. Cross-check of ex-situ and in-situ metrology of a bendable temperature stabilized KB mirror

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Sheng Sam; Goldberg, Kenneth A.; Yashchuk, Valeriy V.; Celestre, Richard; McKinney, Wayne R.; Morrison, Gregory; Macdougall, James; Mochi, Iacopo; Warwick, Tony

    2010-09-15

    At the Advanced Light Source (ALS), we are developing broadly applicable, high-accuracy, in-situ, at-wavelength wavefront slope measurement techniques for Kirkpatrick-Baez (KB) mirror nano-focusing. In this paper, we report an initial cross-check of ex-situ and in-situ metrology of a bendable temperature stabilized KB mirror. This cross-check provides a validation of the in-situ shearing interferometry currently under development at the ALS.

  3. Implementation of an ex situ stabilization technique at the Sand Springs superfund site to solidify and stabilize acid tar sludges involving a quick-lime based stabilization process and innovative equipment design

    Energy Technology Data Exchange (ETDEWEB)

    McManus, R.W. [SOUND Environmental Services, Inc., Dallas, TX (United States); Grajczak, P. [ARCO, Los Angeles, CA (United States); Wilcoxson, J.C. [ARCO, Plano, TX (United States); Webster, S.D. [Environmental Protection Agency, Dallas, TX (United States)

    1997-12-31

    An old refinery site was safely remediated a year before schedule and for 25% less than final engineering estimates for the stabilization remedy thanks to energetic project management and innovative design involving ex situ stabilization/solidification of acid tar sludges. A quicklime based process, Dispersion by Chemical Reaction (DCR{trademark}), was employed to solidify and stabilize (SS) over 103,000 cubic meters (135,000 cubic yards) of petroleum waste, mostly acidic tarry sludge. The SS process was selected over competing methods because it afforded minimal volume increase, could readily achieve Record of Decision (ROD) specified physical and chemical treatment goals, could be implemented with treatment equipment that minimized emissions, and could be performed with low reagent usage and at low cost. To ensure treatment goals were achieved and an accelerated schedule met, a custom designed and fabricated transportable treatment unit (TTU) was employed to implement the process. The treated material was visually soil-like in character, it was left in stockpiles for periods of time, and it was placed and compacted in the on site landfill using standard earth-moving equipment.

  4. Implementation of an ex situ stabilization technique at the Sand Springs superfund site to solidify and stabilize acid tar sludges involving a quick-lime based stabilization process and innovative equipment design

    International Nuclear Information System (INIS)

    An old refinery site was safely remediated a year before schedule and for 25% less than final engineering estimates for the stabilization remedy thanks to energetic project management and innovative design involving ex situ stabilization/solidification of acid tar sludges. A quicklime based process, Dispersion by Chemical Reaction (DCR trademark), was employed to solidify and stabilize (SS) over 103,000 cubic meters (135,000 cubic yards) of petroleum waste, mostly acidic tarry sludge. The SS process was selected over competing methods because it afforded minimal volume increase, could readily achieve Record of Decision (ROD) specified physical and chemical treatment goals, could be implemented with treatment equipment that minimized emissions, and could be performed with low reagent usage and at low cost. To ensure treatment goals were achieved and an accelerated schedule met, a custom designed and fabricated transportable treatment unit (TTU) was employed to implement the process. The treated material was visually soil-like in character, it was left in stockpiles for periods of time, and it was placed and compacted in the on site landfill using standard earth-moving equipment

  5. In-situ synchrotron diffraction and digital image correlation technique for characterizations of retained austenite stability in low-alloyed transformation induced plasticity steel

    International Nuclear Information System (INIS)

    Direct measurement and quantification of phase transformation in a low-alloyed transformation induced plasticity steels depending on the tensile load as well as determination of the real true stress and true strain values were carried out in-situ using high energy synchrotron radiation. Digital image correlation technique was used to quantify more precisely the true strain values. The aim of the work was to obtain a better understanding of the phase transformation of commercial low-alloyed transformation induced plasticity steel depending on the true strain and true stress values.

  6. Chemoport anchoring – the in situ technique

    OpenAIRE

    Yagachikatte Chikkanarasaiah Madhu; Krishnamachar Harish

    2011-01-01

    Chemoports are subcutaneously placed long term central venous access devices usually inserted under local anaesthesia. Rare complications include port inversion or flip over. These can be prevented by anchoring the port to the tissues at its base. We describe an in situ technique of port anchoring. Here, the port is first ‘fixed’ temporarily to the overlying skin by Huber needle, thus facilitating placement of fixing sutures without port manipulation. The described technique is safe and we ha...

  7. In situ vitrification: application analysis for stabilization of transuranic waste

    International Nuclear Information System (INIS)

    The in situ vitrification process builds upon the electric melter technology previously developed for high-level waste immobilization. In situ vitrification converts buried wastes and contaminated soil to an extremely durable glass and crystalline waste form by melting the materials, in place, using joule heating. Once the waste materials have been solidified, the high integrity waste form should not cause future ground subsidence. Environmental transport of the waste due to water or wind erosion, and plant or animal intrusion, is minimized. Environmental studies are currently being conducted to determine whether additional stabilization is required for certain in-ground transuranic waste sites. An applications analysis has been performed to identify several in situ vitrification process limitations which may exist at transuranic waste sites. Based on the process limit analysis, in situ vitrification is well suited for solidification of most in-ground transuranic wastes. The process is best suited for liquid disposal sites. A site-specific performance analysis, based on safety, health, environmental, and economic assessments, will be required to determine for which sites in situ vitrification is an acceptable disposal technique. Process economics of in situ vitrification compare favorably with other in-situ solidification processes and are an order of magnitude less than the costs for exhumation and disposal in a repository. Leachability of the vitrified product compares closely with that of Pyrex glass and is significantly better than granite, marble, or bottle glass. Total release to the environment from a vitrified waste site is estimated to be less than 10-5 parts per year. 32 figures, 30 tables

  8. In situ containment and stabilization of buried waste. Annual report FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    Allan, M.L.; Kukacka, L.E.; Heiser, J.H.

    1992-11-01

    The objective of the project was to develop, demonstrate and implement advanced grouting materials for the in-situ installation of impermeable, durable subsurface barriers and caps around waste sites and for the in-situ stabilization of contaminated soils. Specifically, the work was aimed at remediation of the Chemical Waste (CWL) and Mixed Waste Landfills (MWL) at Sandia National Laboratories (SNL) as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). This report documents this project, which was conducted in two subtasks. These were (1) Capping and Barrier Grouts, and (2) In-situ Stabilization of Contaminated Soils. Subtask 1 examined materials and placement methods for in-situ containment of contaminated sites by subsurface barriers and surface caps. In Subtask 2 materials and techniques were evaluated for in-situ chemical stabilization of chromium in soil.

  9. Latex-modified grouts for in-situ stabilization of buried transuranic/mixed waste

    International Nuclear Information System (INIS)

    The Department of Applied Science at Brookhaven national Laboratory was requested to investigate latex-modified grouts for in-situ stabilization of buried TRU/mixed waste for INEL. The waste exists in shallow trenches that were backfilled with soil. The objective was to formulate latex-modified grouts for use with the jet grouting technique to enable in-situ stabilization of buried waste. The stabilized waste was either to be left in place or retrieved for further processing. Grouting prior to retrieval reduces the potential release of contaminants. Rheological properties of latex-modified grouts were investigated and compared with those of conventional neat cement grouts used for jet grouting

  10. A SURVEY ON VIDEO STABILIZATION TECHNIQUES

    Directory of Open Access Journals (Sweden)

    Patel Amisha

    2015-02-01

    Full Text Available In computer vision, video stabilization is an image processing method to remove visually distributing shaky or unstable motions from videos. This image disturbance may be due to the handshake of the camera holder or platform vibrations in case of surveillance cameras. In order to remove these unsteady motions, video stabilization contains three major step Motion estimation, Motion compensation or Motion smoothing, and Image warping. There are mainly four categories of video stabilization viz., optical stabilization, electronic stabilization, mechanical stabilization, digital stabilization. Digital video stabilization techniques make use only of information drawn from already captured footage and do not need any additional hardware or knowledge about camera physical motion, making it inexpensive and relatively easy to use. Video stabilization is used for astrophotography, tracking targets in military, earth motion etc. Many approaches of video stabilization have been proposed. In this paper provide an analysis of different techniques used for digital video stabilization.

  11. Optical metrology techniques for dimensional stability measurements:

    OpenAIRE

    Ellis, Jonathan David

    2010-01-01

    This thesis work is optical metrology techniques to determine material stability. In addition to displacement interferometry, topics such as periodic nonlinearity, Fabry-Perot interferometry, refractometry, and laser stabilization are covered.

  12. In situ uranium stabilization by microbial metabolites

    International Nuclear Information System (INIS)

    Microbial melanin production by autochthonous bacteria was explored in this study as a means to increase U immobilization in U contaminated soil. This article demonstrates the application of bacterial physiology and soil ecology for enhanced U immobilization in order to develop an in situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE), Savannah River Site (SRS), South Carolina, as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >106 cells per g wet soil. Pyomelanin demonstrated U complexing and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in a field test demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments

  13. IN SITU URANIUM STABILIZATION BY MICROBIAL METABOLITES

    Energy Technology Data Exchange (ETDEWEB)

    Turick, C; Anna Knox, A; Chad L Leverette,C; Yianne Kritzas, Y

    2006-11-29

    Soil contaminated with U was the focus of this study in order to develop in-situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE) Savannah River Site (SRS) as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >106 cells/g wet soil. Pyomelanin demonstrated U chelating and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in field tests demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments.

  14. In situ uranium stabilization by microbial metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Turick, Charles E. [Environmental Science and Biotechnology, Savannah River National Laboratory, Building 999W, Aiken, SC 29808 (United States)], E-mail: Charles.Turick@srnl.doe.gov; Knox, Anna S. [Environmental Science and Biotechnology, Savannah River National Laboratory, Building 999W, Aiken, SC 29808 (United States); Leverette, Chad L.; Kritzas, Yianne G. [Department of Chemistry and Physics, University of South Carolina Aiken, Aiken, SC 29801 (United States)

    2008-06-15

    Microbial melanin production by autochthonous bacteria was explored in this study as a means to increase U immobilization in U contaminated soil. This article demonstrates the application of bacterial physiology and soil ecology for enhanced U immobilization in order to develop an in situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE), Savannah River Site (SRS), South Carolina, as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >10{sup 6} cells per g wet soil. Pyomelanin demonstrated U complexing and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in a field test demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments.

  15. Efficient technique for measuring laser frequency stability

    OpenAIRE

    Sargsyan, A.; Papoyan, A. V.; Sarkisyan, D.; Weis, Antoine

    2009-01-01

    We propose a new technique for measuring the frequency stability of cw laser radiation. The technique relies on using the laser to be tested as a coupling laser in a scheme of electromagnetically-induced transparency (EIT), either on a ? or a ladder system. A second, frequency tunable laser (stabilization of this laser is not needed) is used both to act as the EIT probe laser, and to form an atomic frequency reference spectrum. The frequency stability is monitored via the frequency deviation...

  16. Stabilization of contaminated soils by in situ vitrification

    International Nuclear Information System (INIS)

    In situ methods are preferred for the stabilization or restoration of soil sites contaminated with elevated levels of hazardous materials (e.g., radionuclides, metals, organics) to minimize potential risks to personnel and the environment associated with removal and treatment. In situ methods available include polymer and silicate grouting, compaction, chemical treatment, groundwater diversion, and vitrification. Of these, in situ vitrification (ISV) is most desirable because it is more a permanent solution and produces a final waste form with the most preferred characteristics. The ISV product, generally a mixture of glass and crystals, has high strength, is resistant to leaching, and has low porosity and permeability. Results are presented on an ISV test at an Oak Ridge Laboratory Site

  17. In-situ stabilization of mixed waste contaminated soil

    International Nuclear Information System (INIS)

    A full-scale field demonstration was conducted to evaluate in for stabilizing an inactive RCRA land treatment site at a DOE facility in Ohio. Subsurface silt and clay deposits were contaminated principally with up to 500 mg/kg of trichloroethylene and other halocarbons, but also trace to low levels of Pb, Cr, 235U, and 99Tc. In situ solidification was studied in three, 3.1 m diameter by 4.6 m deep columns. During mixing, a cement-based grout was injected and any missions from the mixed region were captured in a shroud and treated by filtration and carbon adsorption. During in situ processing, operation and performance parameters were measured, and soil cores were obtained from a solidified column 15 months later. Despite previous site-specific treatability experience, there were difficulties in selecting a grout with the requisite treatment agents amenable to subsurface injection and at a volume adequate for distribution throughout the mixed region while minimizing volume expansion. observations during the demonstration revealed that in situ solidification was rapidly accomplished (e.g., >90 m3/d) with limited emissions of volatile organics (i.e., -6 cm/s vs. 10-8 cm/s). Leaching tests performed on the treated samples revealed non-detectable to acceptably low concentrations of all target contaminants

  18. In-situ vacuum deposition technique of lithium on neutron production target for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Ishiyama, S. [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Baba, Y., E-mail: baba.yuji@jaea.go.jp [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Fujii, R.; Nakamura, M.; Imahori, Y. [Cancer Intelligence Care Systems, Inc., Ariake 3-5-7, Koutou-ku, Tokyo 135-0063 (Japan)

    2012-10-01

    For the purpose of avoiding the radiation blistering of the lithium target for neutron production in BNCT (Boron Neutron Capture Therapy) device, trilaminar Li target, of which palladium thin layer was inserted between cupper substrate and Li layer, was newly designed. In-situ vacuum deposition and electrolytic coating techniques were applied to validate the method of fabrication of the Li/Pd/Cu target, and the layered structures of the synthesized target were characterized. In-situ vacuum re-deposition technique was also established for repairing and maintenance for lithium target damaged. Following conclusions were derived; (1) Uniform lithium layers with the thickness from 1.6 nm to a few hundreds nanometer were formed on Pd/Cu multilayer surface by in situ vacuum deposition technique using metallic lithium as a source material. (2) Re-deposition of lithium layer on Li surface can be achieved by in situ vacuum deposition technique. (3) Small amount of water and carbonate was observed on the top surface of Li. But the thickness of the adsorbed layer was less than monolayer, which will not affect the quality of the Li target. (4) The formation of Pd-Li alloy layer was observed at the Pd and Li interface. The alloy layer would contribute to the stability of the Li layer.

  19. Stabilization of contaminated soils by in situ vitrification

    International Nuclear Information System (INIS)

    In Situ Vitrification is an emerging technology developed by Pacific Northwest Laboratory for potential in-place immobilization of radioactive wastes. The contaminated soil is stabilized and converted to an inert glass form. This conversion is accomplished by inserting electrodes in the soil and establishing an electric current between the electrodes. The electrical energy causes a joule heating effect that melts the soil during processing. Any contaminants released from the melt are collected and routed to an off-gas treatment system. A stable and durable glass block is produced which chemically and physically encapsulates any residual waste components. In situ vitrification has been developed for the potential application to radioactive wastes, specifically, contaminated soil sites; however, it could possibly be applied to hazardous chemical and buried munitions waste sites. The technology has been developed and demonstrated to date through a series of 21 engineering-scale tests [producing 50 to 1000 kg (100 to 2000 lb) blocks] and seven pilot-scale tests [producing 9000 kg (20,000 lb) blocks], the most recent of which illustrated treatment of actual radioactively contaminated soil. Testing with some organic materials has shown relatively complete thermal destruction and incineration. Further experiments have documented the insensitivity of in situ vitrification to soil characteristics such as fusion temperature, specific heat, thermal conductivity, electrical resisat, thermal conductivity, electrical resistivity, and moisture content. Soil inclusions such as metals, cements, ceramics, and combustibles normally present only minor process limitations. Costs for hazardous waste applications are estimated to be less than $175/m3 ($5.00/ft3) of material vitrified. For many applications, in situ vitrification can provide a cost-effective alternative to other disposal options. 13 references, 4 figures, 1 table

  20. 40 CFR 1065.195 - PM-stabilization environment for in-situ analyzers.

    Science.gov (United States)

    2010-07-01

    ...thermodynamic conditions within the environment before measuring PM: ...meet the PM-stabilization environment specifications in subpart...the in-situ stabilization environment is within the tolerances...Isolate the balance from any external noise and vibration...

  1. In-situ containment and stabilization of buried waste

    International Nuclear Information System (INIS)

    In FY 1993 research continued on development and testing of grout materials for in-situ containment and stabilization of buried waste. Specifically, the work was aimed at remediation of the Chemical Waste Landfill (CWL) at Sandia National Laboratories (SNL) in Albuquerque, New Mexico as part of the Mixed Waste Landfill Integrated Demonstration (MWLID). The work on grouting materials was initiated in FY 1992 and the accomplishments for that year are documented in the previous annual report (Allan, Kukacka and Heiser, 1992). The remediation plan involves stabilization of the chromium plume, placement of impermeable vertical and horizontal barriers to isolate the landfill and installation of a surface cap. The required depth of subsurface barriers is approximately 33 m (100 ft). The work concentrated on optimization of grout formulations for use as grout and soil cement barriers and caps. The durability of such materials was investigated, in addition to shrinkage cracking resistance, compressive and flexural strength and permeability. The potential for using fibers in grouts to control cracking was studied. Small scale field trials were conducted to test the practicality of using the identified formulations and to measure the long term performance. Large scale trials were conducted at Sandia as part of the Subsurface Barrier Emplacement Technology Program. Since it was already determined in FY 1992 that cementitious grouts could effectively stabilize the chromium plume at the CWL after pre-treatment is performed, the majority of the work was devoted to the containment aspect

  2. In situ stabilization of soil lead using phosphorus.

    Science.gov (United States)

    Hettiarachchi, G M; Pierzynski, G M; Ransom, M D

    2001-01-01

    In situ stabilization of Pb-contaminated soils can be accomplished by adding phosphorus. The standard remediation procedure of soil removal and replacement currently used in residential areas is costly and disruptive. This study was carried out to evaluate the influence of P and other soil amendments on five metal-contaminated soils and mine wastes. Seven treatments were used: unamended control; 2,500 mg of P/kg as triple superphosphate (TSP), phosphate rock (PR), acetic acid followed by TSP, and phosphoric acid (PA); and 5,000 mg of P/kg as TSP or PR. A significant reduction in bioavailable Pb, as determined by the physiologically based extraction test (PBET), compared with the control upon addition of P was observed in all materials tested. Increasing the amount of P added from 2,500 to 5,000 mg/kg also resulted in a significantly greater reduction in bioavailable Pb. Phosphate rock was equally or more effective than TSP or PA in reducing bioavailable Pb in four out of five soils tested. Preacidification produced significantly lower bioavailable Pb compared with the same amount of P from TSP or PR in only one material. Reductions in Pb bioavailability as measured by PBET were evident 3 d after treatment, and it may indicate that the reactions between soil Pb and P occurred in situ or during the PBET. No further reductions were noted over 365 d. X-ray diffraction data suggested the formation of pyromorphite-like minerals induced by P additions. This study suggests that P addition reduced bioavailable Pb by PBET and has potential for in situ remediation of Pb-contaminated soils. PMID:11476498

  3. Dispersion stabilization of silver nanoparticles in synthetic lung fluid studied under in situ conditions

    Energy Technology Data Exchange (ETDEWEB)

    MacCuspie, R.I.; Allen, A.J.; Hackley, V.A. (NIST)

    2014-09-24

    The dispersion stabilization of silver nanoparticles (AgNPs) in synthetic lung fluid was studied to interrogate the effects on colloidal stability due to the principal constituents of the fluid. The colloidal stability of 20 nm citrate-AgNPs dispersed in the presence of each constituent of the synthetic lung fluid (individually, the complete fluid, and without additives) was observed during titration of increasing sodium chloride concentration. A variety of complementary in situ measurement techniques were utilized, including dynamic light scattering, ultraviolet-visible absorption spectroscopy, atomic force microscopy, and small-angle X-ray scattering, which provided a collective set of information that enabled far better understanding of the dispersion behavior in the fluid than any one technique alone. It was observed that AgNPs continued to adsorb bovine serum albumin (BSA) protein from the synthetic lung fluid solution as the sodium chloride concentration increased, until a maximum BSA coating was achieved prior to reaching the physiological sodium chloride concentration of 154 mmol L{sup -1}. BSA was determined to be the constituent of the synthetic lung fluid that is required to provide colloidal stability at high salt loadings, though the phospholipid constituent exerts a subtle effect. Additionally, as AgNPs are a distinctly different class of nanoparticles apart from the carbon nanotubes and titanium dioxide nanoparticles initially reported to be dispersible using this fluid, this work also demonstrates the broad applicability of synthetic lung fluid in providing stable dispersions for engineered nanoparticles for use in biological assays.

  4. Engineering feasibility analysis for in-situ stabilization of Canonsburg residues

    International Nuclear Information System (INIS)

    The US Department of Energy is considering several methods for carrying out remedial actions in Canonsburg, Pennsylvania, at the site of an inactive uranium-processing mill. The main objective of this study is to determine the feasibility of in-situ stabilization as the remedial action. In-situ stabilization is an alternative to site decontamination and offsite disposal. The problems associated with offsite hauling of large quantities of contaminated material and with the location and development of a new disposal site could be avoided by the implementation of an in-situ stabilization concept. In addition, the in-situ approach would be more cost-effective than offsite disposal. This study will establish that a technically feasible and implementable in-situ stabilization concept can be developed that meets regulatory requirements and is cost effective. This study in no way commits the DOE to implement any specific actions described herein. 11 refs., 30 figs., 24 tabs

  5. A novel natural analog in situ stabilization agent

    International Nuclear Information System (INIS)

    This report summarizes the laboratory-scale test results on a synthetic analog of natural hematite cement for potential as an in situ treatment and stabilization agent for buried hazardous and radioactive waste. The concept is based on the principle that the ideal waste isolation materials are synthetic analogs of those natural encapsulating materials (cements), which are in equilibrium with the environment in which they occur. If equilibrium is achieved, then such materials will remain intact as long as the natural environment remains unchanged. The specific waste application is long-term stabilization of transuranic-contaminated waste pits and trenches at the Idaho National Engineering Laboratory (INEL). Six properties of the natural analog agent and resulting wasteforms are discussed to access the agent's effectiveness and implementability: hydraulic conductivity; compressive strength; mineralogy and microstructure; compatibility with possible waste materials, nitrates, machine cutting oil, and metallic iron; leachability of hazardous metals; and field application parameters. Data indicated that the iron waste encapsulation materials tested are appropriate choices for buried waste mixed with INEL soil. Iron oxide/gypsum INEL soil wasteforms have hydraulic conductivity values close to the regulatory limit. Wasteforms with soil and wastes have compressive strength greater than the regulatory minimum. Gypsum/iron oxide removes hazardous metals from solution by adsorpt hazardous metals from solution by adsorption and would pass Toxicity Characteristic Leaching Procedure limits for most toxic metals. It appears to be chemically and physically inert with respect to the bulk of the waste materials likely to be found at INEL, and has properties conducive to jet grouting

  6. In situ solidification/stabilization pilot study for the treatment of coal tar contaminated soils and river sediments

    International Nuclear Information System (INIS)

    Coal tar contamination was encountered at a former coal gasification site in soils below the groundwater table, and in the sediments of the adjacent river. Ex situ remediation techniques at this site would be costly because of the need to dewater the impacted media. In situ solidification/stabilization was tested to evaluate its effectiveness. Treatability testing was performed to evaluate a Portland cement/fly ash binder system with added stabilizing agents. Results were sufficiently promising to warrant pilot testing. Grout containing Portland cement, fly ash, organically modified clay, and granular activated carbon was pilot tested at the site. Test specimens were collected and tested to evaluate durability, compressive strength, and permeability. The samples were extracted by several methods and analyzed to measure the leachable concentrations of organic compounds and metals. Results indicated acceptable physical characteristics. Leachable concentrations of most polynuclear aromatic compounds were decreased

  7. COMPARISON OF DIFFERENT TECHNIQUES FOR DESIGN OF POWER SYSTEM STABILIZER

    Directory of Open Access Journals (Sweden)

    M. Ravindra Babu,

    2011-05-01

    Full Text Available The major problem in power system operation is related to small signal instability caused by insufficient damping in the system. The most effective way of countering this instability is to use auxiliary controllers called power system stabilizers, to produce additional damping during low frequency oscillations in the system. Heffron-Phillip’s Model of a synchronous machine is commonly used in small signal stability analysis. Different techniques for designing of power system stabilizer is proposed for Modified Heffron-Phillip’smodel, the parameters of the power system stabilizer has been tuned by the three ways , linear quadratic power system stabilizer, genetic algorithm power system stabilizer and proposed power system stabilizer. The efficiency of the proposed design technique and the performance of the stabilizer has been evaluated over a range of operating and system conditions and the performance of the proposed controller is much better than the linear quadratic power system stabilizer and genetic algorithm based power system stabilizer.

  8. Well completion for in situ heating oil recovery technique

    Energy Technology Data Exchange (ETDEWEB)

    Chacon, O. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of). INTEVEP

    2009-07-01

    This paper discussed thermal well completion technologies for use in Venezuela's heavy and extra-heavy oil reservoirs. A review and comparison of thermal well completions was conducted and a specialized software program was used to select appropriate well completion technologies for an oilfield in Venezuela's Orinoco oil belt. The study focused on in situ combustion (ISC) methods that inject air into the reservoir while igniting the oil to generate a combustion front. The method was shown to increase oil mobility and facilitate its displacement towards production wells. Cemented and perforated liners were evaluated in this study along with methods for preparing injection wells. Methods of controlling sand production during ISC were also discussed and steam flooded and ISC well completion techniques were compared. The thermal loads for well completions undergoing ISC processes were analyzed. A tubing stress analysis was also presented. It was concluded that the simulations validated the proposed ISC well completion strategy. 6 refs., 4 tabs., 4 figs.

  9. In-situ stabilization of the Geiger (C and M Oil) Superfund Site

    International Nuclear Information System (INIS)

    The Geiger (C and M Oil) Superfund Site is the first US Army Corps of Engineers managed soil remediation project which utilized the in-situ stabilization/solidification technique to remediate the soil. This project involved the remediation of approximately 23,000 cubic yards of contaminated soil. Contaminants of concern included chromium, lead, PCB'S, toluene, benzene, and other organic compounds. Clean-up criteria for the stabilized material was equal to the National Primary Drinking Water Regulations, when tested using the TCLP leachate extraction method. Chromium, lead, and toluene were the main contaminants of concern, with TCLP clean-up goals of 150, 15 and 1,000 parts per billion (ppb), respectively. This National Priorities List (NPL) site is located near Charleston, SC and was an abandoned old waste oil facility that utilized unlined shallow trenches for the storage of waste oil. This paper summarizes the initial testing programs and the final production work at the site. Extensive testing was performed throughout all phases of the project. This testing was performed for the purpose of mix optimization, quality assurance, and verification testing. Specific parameters tested included: TCLP testing of organics, metals and PCBs, permeability testing, and unconfirmed compression strength

  10. In Situ Mercury Stabilization (ISMS) Treatment: Technology Maturation Project Phase I Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Kalb,P.D.; Milian, L.

    2008-03-01

    Mercury (Hg) was used to separate lithium-6 isotope for weapons production at the Y-12 Plant in Oak Ridge in the 1950s and 1960s. As much as two million pounds of elemental mercury was 'lost' or unaccounted for and a large portion of that material is believed to have entered the environment. The DOE site office in Oak Ridge has identified Hg pollution in soils, sediments, and streams as the most significant environmental challenge currently faced. In industry, large amounts of mercury have been used to manufacture products (e.g., fluorescent light bulbs, thermometers) and for chemical processing (e.g., production of chlorine and alkali via mercury electrochemical cells) and many of these industrial sites are now polluted with mercury contaminated soil as a result of previous releases and/or inadvertent leaks. Remediation techniques for Hg contaminated soils are either based on thermal desorption and recovery of the mercury or excavation and shipping of large volumes of material to remote facilities for treatment and disposal. Both of these alternatives are extremely costly. The Brookhaven National Laboratory (BNL) Environmental Research & Technology Division (ERTD) has demonstrated, in laboratory-scale experiments, the viability of treating mercury contaminated soils by means of sulfide treatment rods inserted into the soil through a process known as In Situ Mercury Stabilization (ISMS). This approach is partly based on BNL's patented and successfully licensed ex situ process for Hg treatment, Sulfur Polymer Stabilization/Solidification (SPSS) which converts Hg to the more stable sulfide form. The original experiments showed that Hg homogeneously distributed in soil rapidly migrates to form a high concentration zone of chemically stable mercuric sulfide near the treatment rods while concentrations of Hg in surrounding areas away from the treatment rods are depleted to acceptable levels. BSA has subsequently filed for patent protection on the ISMS technology. If further developed it has the potential for large-scale in-situ treatment of contaminated soils that could substantially reduce the prohibitive cost of thermal desorption and/or excavation and disposal. Licensing and spin-off technology development opportunities would then be viable. Depending on performance and regulatory acceptance, the treated mercury could either be excavated for disposal elsewhere or left in place as a stable alternative. Excavated spent treatment rods could be processed by the SPSS process to reduce the potential for dispersion and lower leachability even further. The Phase I objectives of the In Situ Mercury Stabilization Treatment Process Technology Maturation Project were to: (1) replicate the original bench-scale results that formed the basis for BNL's patent application, i.e., mercury contamination in soil will migrate to and react with 'rods' containing sulfur and/or sulfur compounds, (2) provide enough information to evaluate a decision to conduct further development, and (3) establish some of the critical parameters that require further technology maturation during Phase II. The information contained in this report summarizes the work conducted in Phase I to meet these objectives.

  11. Transient Stability Assessment using Decision Trees and Fuzzy Logic Techniques

    Directory of Open Access Journals (Sweden)

    A. Y. Abdelaziz

    2013-09-01

    Full Text Available Many techniques are used for Transient Stability assessment (TSA of synchronous generators encompassing traditional time domain state numerical integration, Lyapunov based methods, probabilistic approaches and Artificial Intelligence (AI techniques like pattern recognition and artificial neural networks.This paper examines another two proposed artificial intelligence techniques to tackle the transient stability problem. The first technique is based on the Inductive Inference Reasoning (IIR approach which belongs to a particular family of machine learning from examples. The second presents a simple fuzzy logic classifier system for TSA. Not only steady state but transient attributes are used for transient stability estimation so as to reflect machine dynamics and network changes due to faults.The two techniques are tested on a standard test power system. The performance evaluation demonstrated satisfactory results in early detection of machine instability. The advantage of the two techniques is that they are straightforward and simple for on-line implementation.

  12. Alcohol oxidase protein mediated in-situ synthesized and stabilized gold nanoparticles for developing amperometric alcohol biosensor.

    Science.gov (United States)

    Chinnadayyala, Somasekhar R; Santhosh, Mallesh; Singh, Naveen K; Goswami, Pranab

    2015-07-15

    A simple one step method for the alcohol oxidases (AOx) protein mediated synthesis of gold nano-particles (AuNPs) in alkaline (pH 8.5) condition with simultaneous stabilization of the nanoparticles on the AOx protein surface under native environment has been developed. The formation of the AOx conjugated AuNPs was confirmed by advanced analytical and spectroscopic techniques. The significant increase in zeta potential (?) value of -57mV for the synthesized AOx-AuNPs conjugate from the AOx (pI 4.5) protein (?, -30mV) implied good stability of the in-situ synthesized nano-conjugate. The AOx-AuNPs conjugate showed steady stability in alkaline (upto pH 8.5) and NaCl (up to 10(-1)M) solutions. The efficiency (Kcat/Km) of the AuNP conjugated AOx was increased by 18% from the free enzyme confirming the activating role of the surface stabilized AuNPs for the enzyme. The AuNPs-AOx conjugate was encapsulated with polyaniline (PANI) synthesized by oxidative polymerization of aniline using H2O2 generated in-situ from the AOx catalysed oxidation of alcohol. The PANI encapsulated AuNPs-AOx assembly was stabilized on a glassy carbon electrode (GCE) by chitosan-Nafion mixture and then utilized the fabricated bioelectrode for detection of alcohol amperometrically using H2O2 as redox indicator at +0.6V. The constructed biosensor showed high operational stability (6.3% loss after 25 measurements), wide linear detection range of 10µM-4.7mM (R(2)=0.9731), high sensitivity of 68.3±0.35µAmM(-1) and low detection limit of 7±0.027µM for ethanol. The fabricated bioelectrode was successfully used for the selective determination of alcohol in beverage samples. PMID:25725464

  13. Experimental techniques for mass measurement far from stability

    International Nuclear Information System (INIS)

    The measurement of nuclear masses is a fundamental tool to probe nuclear structure ar from stability. A review of the techniques that have been most commonly employed to undertake such measurements is presented. (author)

  14. Routine application of the in situ soil analysis technique by the Yankee Atomic Environmental Laboratory

    International Nuclear Information System (INIS)

    Using a technique developed by the Environmental Measurements Laboratory (EML) for field spectrometry, the Yankee Atomic Environmental Laboratory (YAEL) has routinely performed in situ soil measurements in the vicinity of five nuclear power stations for more than a decade. As a special research endeavor, several locations at the FURNAS Angra 1 site in Brazil having high natural backgrounds were also measured in 1987. The technical basis of the technique, a comparison of soil radionuclide concentrations predicted by the in situ technique to soil radionuclide concentrations predicted by the in situ technique to soil analyses from the same sites, the advantages and disadvantages of the in situ methodology, and the evolution of the portable equipment utilized at YAEL for the field measurements are presented in this paper

  15. Investigating structure-property relationships in cathode materials via combined ex-situ and in-situ diffraction techniques

    International Nuclear Information System (INIS)

    While anode and electrolyte materials continue to see significant advances, cathode materials remain underdeveloped in comparison. As a battery's performance is determined by its weakest component further improvements to cathode materials are essential. Given the complex chemical and structural changes which can take place in cathode materials on cycling, a range of advanced characterization techniques must be utilised in order to understand the properties well enough to then improve upon them. A combination and ex-situ type dialyses has been performed on the cathode material Li0.18Sr0.66Ti0.5BNb0.5O3. Ex-situ neutron diffraction experiments, following the chemical insertion of lithium enabled the location of lithium within the structure to be accurately determined through Rietveld refinement and calculation of Fourier difference maps. More significantly, the evolution of phases and structural change in this material has been followed utilizing both in-situ neutron and synchrotron diffraction experiments. Sequential Rietveld refinements have allowed the change in structure to be directly correlated with the observed electrochemical properties. Specifically, due to the real time collection of structure; data as a function of discharge. the rate of structural change was measured and directly correlated with electrochemical portfolio. This contribution will demonstrate how a combination of ex-situ diffraction of chemical and electrochemical insertion of lithium as well as in-situ diffraction of electrochemical insertion of lithium can provide a robust picture of how the structure influences properties.

  16. Ion exchange blinding-preventing technique of in-situ uranium leaching in Qianerkuai uranium deposit

    International Nuclear Information System (INIS)

    Qianerkuai uranium deposit contains high carbonates and rich clay. It is a low penetrability sandstone uranium ore which can be exploited by in-situ leaching technique. During the pilot production, the blinding phenomena occurred because of its low penetrability. According to the in-situ uranium leaching mechanism, the 001 x 7 cation exchange resin was selected to remove Ca2+ and Mg2+ from the injection liquid, which are the main cations to form the precipitation. The experiment results show that the removal effect of Ca2+ and Mg2+ is excellent. This technique can be applied in in-situ leaching of uranium. (authors)

  17. Power system stabilizers based on modern control techniques

    Energy Technology Data Exchange (ETDEWEB)

    Malik, O.P.; Chen, G.P.; Zhang, Y.; El-Metwally, K. [Calgary Univ., AB (Canada). Dept. of Electrical and Computer Engineering

    1994-12-31

    Developments in digital technology have made it feasible to develop and implement improved controllers based on sophisticated control techniques. Power system stabilizers based on adaptive control, fuzzy logic and artificial networks are being developed. Each of these control techniques possesses unique features and strengths. In this paper, the relative performance of power systems stabilizers based on adaptive control, fuzzy logic and neural network, both in simulation studies and real time tests on a physical model of a power system, is presented and compared to that of a fixed parameter conventional power system stabilizer. (author) 16 refs., 45 figs., 3 tabs.

  18. In-situ containment and stabilization of buried waste: Annual report FY 1994

    International Nuclear Information System (INIS)

    The two landfills of specific interest are the Chemical Waste Landfill (CWL) and the Mixed Waste Landfill (MWL), both located at Sandia National Laboratory. The work is comprised of two subtasks: (1) In-Situ Barriers and (2) In-Situ Stabilization of Contaminated Soils. The main environmental concern at the CWL is a chromium plume resulting from disposal of chromic acid and chromic sulfuric acid into unlined pits. This program has investigated means of in-situ stabilization of chromium contaminated soils and placement of containment barriers around the CWL. The MWL contains a plume of tritiated water. In-situ immobilization of tritiated water with cementitious grouts was not considered to be a method with a high probability of success and was not pursued. This is discussed further in Section 5.0. Containment barriers for the tritium plume were investigated. FY 94 work focused on stabilization of chromium contaminated soil with blast furnace slag modified grouts to bypass the stage of pre-reduction of Cr(6), barriers for tritiated water containment at the MWL, continued study of barriers for the CWL, and jet grouting field trials for CWL barriers at an uncontaminated site at SNL. Cores from the FY 93 permeation grouting field trails were also tested in FY 94

  19. Stabilization of microorganisms for in situ degradation of toxic chemicals

    International Nuclear Information System (INIS)

    Methods for large-scale microencapsulation of bacteria and nutrients into microbeads with small enough diameters to travel through aquifers have been developed at the University of Idaho. Both free and immobilized cells of Flavobacterium ATCC 39723, a gram-negative aerobe that degrades various chlorinated phenols, into aquifer microcosms, through which pentachlorophenol (PCP)-contaminated groundwater flowed at in situ flow rates. Aquifer samples were collected with an auger from three wells at the University of Idaho Ground Water Research Site, and packed into 24 columns. Some sterile columns were also prepared, by irradiation at the Washington State University Radiation Center. In some of the columns the free Flavobacterium cells were mixed with the aquifer material before packing the columns. In others, agarose-microimmobilized Flavobacterium were mixed into the aquifer material. The effluent from each column was collected daily for 170 days and analyzed by UV spectroscopy or HPLC for remaining PCP. There were no statistically significant differences between the degradation rates of free or encapsulated Flavobacterium in sterile or native aquifer material as tested in these experiments. This work has shown at the lab scale that encapsulated PCP-degrading Flavobacterium were able to survive under conditions of starvation, predation, and lack of water

  20. Application of in-situ XRF technique on some aeromagnetic anomalies point of Xitianshan

    International Nuclear Information System (INIS)

    In-situ X-ray fluorescence technique is a convenient, efficient and economic field survey technique. In the project the technique was applied to the determining concentrations of Fe, Cu, Zn, Pb, As, Mn, Ni, in rock outcrops and soil of the aeromagnetic anomalies areas and we analysed distributions of these elements for aeromagnetic anomalies evaluation to provide the basis. It comes to a conclusion that in-situ X-ray fluorescence technique provides a convenient and fast method for aeromagnetic anomalies confirmation. (authors)

  1. In-situ vein bypass: a modified technique.

    OpenAIRE

    Galland, R. B.; Young, A. E.; Jamieson, C. W.

    1981-01-01

    The preliminary results and operative details are presented of a new way of undertaking an in-situ vein bypass in which the vein is distended by blood under arterial pressure before the valves are destroyed. The results are encouraging; 7 of the distal anastomoses were to small calf vessels and at a follow-up of at least 6 months 17 of 20 limbs are improved.

  2. Cervical Spine Motion during Transfer and Stabilization Techniques.

    Science.gov (United States)

    Shrier, Ian; Boissy, Patrick; Lebel, Karina; Boulay, John; Segal, Eli; Delaney, J Scott; Vacon, L Charlene; Steele, Russell J

    2015-01-01

    Abstract Objectives. To compare paramedics' ability to minimize cervical spine motion during patient transfer onto a vacuum mattress with two stabilization techniques (head squeeze vs. trap squeeze) and two transfer methods (log roll with one assistant (LR2) vs. 3 assistants (LR4)). Methods. We used a crossover design to minimize bias. Each lead paramedic performed 10 LR2 transfers and 10 LR4 transfers. For each of the 10 LR2 and 10 LR4 transfers, the lead paramedic stabilized the cervical spine using the head squeeze technique five times and the trap squeeze technique five times. We randomized the order of the stabilization techniques and LR2/LR4 across lead paramedics to avoid a practice or fatigue effect with repeated trials. We measured relative cervical spine motion between the head and trunk using inertial measurement units placed on the forehead and sternum. Results. On average, total motion was 3.9° less with three assistants compared to one assistant (p = 0.0002), and 2.8° less with the trap squeeze compared to the head squeeze (p = 0.002). There was no interaction between the transfer method and stabilization technique. When examining specific motions in the six directions, the trap squeeze generally produced less lateral flexion and rotation motion but allowed more extension. Examining within paramedic differences, some paramedics were clearly more proficient with the trap squeeze technique and others were clearly more proficient with the head squeeze technique. Conclusion. Paramedics performing a log roll with three assistants created less motion compared to a log roll with only one assistant, and using the trap squeeze stabilization technique resulted in less motion than the head squeeze technique but the clinical relevance of the magnitude remains unclear. However, large individual differences suggest future paramedic training should incorporate both best evidence practice as well as recognition that there may be individual differences between paramedics. PMID:25076192

  3. Thermal Stability and Properties of Deformation-Processed Cu-Fe In Situ Composites

    Science.gov (United States)

    Liu, Keming; Jiang, Zhengyi; Zhao, Jingwei; Zou, Jin; Lu, Lei; Lu, Deping

    2015-05-01

    This paper investigated the thermal stability, tensile strength, and conductivity of deformation-processed Cu-14Fe in situ composites produced by thermo-mechanical processing. The thermal stability was analyzed using scanning electronic microscope and transmission electron microscope. The tensile strength and conductivity were evaluated using tensile-testing machine and micro-ohmmeter, respectively. The Fe fibers in the deformation-processed Cu-14Fe in situ composites undergo edge recession, longitudinal splitting, cylinderization, break-up, and spheroidization during the heat treatment. The Cu matrix experiences recovery, recrystallization, and precipitation phase transition. The tensile strength and conductivity first increase with increasing temperature of heat treatment, reach peak values at different temperatures, and then decrease at higher temperatures. The value of parameter Z of the in situ composite reaches the peak of 2.86 × 107 MPa2 pct IACS after isothermal heat treatment at 798 K (525 °C) for 1 hour. The obtained tensile strength and conductivity of the in situ composites are 907 MPa and 54.3 pct IACS; 868 MPa and 55.2 pct IACS; 810 MPa and 55.8 pct IACS; or 745 MPa and 57.4 pct IACS, at ? = 7.8 after isochronal heat treatment for 1 hour.

  4. Switchable pickering emulsions stabilized by silica nanoparticles hydrophobized in situ with a switchable surfactant.

    Science.gov (United States)

    Jiang, Jianzhong; Zhu, Yue; Cui, Zhenggang; Binks, Bernard P

    2013-11-18

    Back and forth: The CO2 /N2 trigger of a switchable surfactant (neutral amidine/cationic amidinium) was transferred to mineral nanoparticles through in?situ hydrophobization in water. Switchable oil-in-water Pickering emulsions that entail a CO2 /N2 trigger were obtained by using negatively charged silica nanoparticles and a trace amount of the switchable surfactant as the stabilizer. PMID:24123666

  5. Indigenous development of A-15 superconductors through in situ technique

    International Nuclear Information System (INIS)

    The preliminary results obtained on the in situ Cu-Nb3Sn composite superconductors are reported. Two phase alloys of Cu-Nb (15 to 30 at.%) have been prepared by arc melting and rolled/drawn to fine wires and tapes without intermediate annealing. Prior to tin coating, these specimens were characterized for their T/sub c/ and J/sub c/ values. A mid point T/sub c/ of 8.8K and a self field overall J/sub c/ of 2.5 x 105 A.cm-2 (4.2K) have been obtained for specimens with 20 to 30 at.% Nb. The rolled Cu-Nb tapes with well aligned filaments show critical current anisotropy with the magnetic field direction. Cu-Nb3Sn composite wires have been prepared by coating these wires with varying amounts of tin and heat treating them at 5500C for various periods. The best specimen has a T/sub c/ (midpoint) of 17.5K and a J/sub c/ of 3 x 105 A.cm-2 at 6T, 4.2K and 3 x 104 A.cm-2 at 12T, 4.2K. These values compare well with the published data. Studies are continuing for the optimization of various parameters. In situ Cu-V3Ga composite wires have also been prepared and are presently begin characterized

  6. In situ stabilization of mixed radioactive waste storage tanks and contaminated soil areas

    International Nuclear Information System (INIS)

    Within the Department of Energy (DOE) Complex, there are a number of small (<50,000 gallons) underground Storage tanks containing mixed waste materials. The radioactive content of wastes eliminates the feasibility for hazardous waste treatment in accordance with previously prescribed Resource Conservation and Recovery Act (RCRA) technologies. As a result, DOE is funding in situ stabilization technology development for these tanks, Some of this development work has been done at the Idaho National Engineering and Environmental Laboratory (INEEL) and the initial efforts there were concentrated on the stabilization of the contents of the Test Area North (TAN) V-9 Tank. This is a 400 gallon underground tank filled with about 320 gallons of liquids and silty sediments. Sampling data indicates that approximately 50 wt% of the tank contents is aqueous-phase liquids. The vertically oriented cylindrical tank has a conical bottom and a chordal baffle that separates the tank inlet from its outlet. Access to the tank is through a six inch diameter access pipe on top of the tank. Because of the high volume, and the high concentration of aqueous-phase materials, Tank V-9 stabilization efforts have focussed on applying in situ agitation with dry feed addition to stabilize its contents. Materials selected for dry feed addition to this tank include a mixture of Aquaset IIH, and Type I/II Portland cement. This paper describes the results of proof-of-concept tests performed on full scale mockups of the Tank V-9. This proof-of-concept test were used to set operating parameters for in situ mixing, as well as evaluate how variations in Aquaset IIH/Portland cement ratio and sediment to liquid volume affected mixing of the tank

  7. In Situ Techniques for Monitoring Electrochromism: An Advanced Laboratory Experiment

    Science.gov (United States)

    Saricayir, Hakan; Uce, Musa; Koca, Atif

    2010-01-01

    This experiment employs current technology to enhance and extend existing lab content. The basic principles of spectroscopic and electroanalytical techniques and their use in determining material properties are covered in some detail in many undergraduate chemistry programs. However, there are limited examples of laboratory experiments with in…

  8. Application of in situ x-ray diffraction techniques in heterogenous catalytic systems

    International Nuclear Information System (INIS)

    A broad range of techniques is available today for the characterisation of catalysts and the investigation of catalyst reaction mechanisms. However, only a limited number of those are suitable for in situ studies, i.e experiments performed in conditions mimicking or close as possible to real operating conditions. Various commercially and in-house developed in situ X-Ray diffraction (XRD) cells have been used to obtain information on the phase and structure of materials at the initial formation stage, activation methodology, calcination, reduction and carburization. A major advantage of the in situ X-ray cells is that it allows direct observations on the decomposition of precursors leading to various phases in a controlled environment, i.e. controlled temperature and pressure under specified gases. The cells can be operated both at high temperatures and high pressures, equipped with Position Sensitive Detector (PSD), feature which was used to study phase transformation occurring during the activation of various solids. In MoO3, XRD results provide detailed information on the hydrogen insertion into its lattice, followed by carburization providing good understanding on the mechanism in the solid transformation leading to the metastable MoC1-x phase. For the Bi-SnOx systems, the environmental cell coupled with XRD and PSD allow the design of activation procedure to obtain the active Bi2Sn2O7. The in situ XSn2O7. The in situ XRD technique reveals crucial information on the initial stage of oxides formations prior to condensation reaction shown in MCM-41 and titania systems. In this presentation, discussions on general achievements and problems relating to the use of in situ XRD techniques as well as of specific examples selected to illustrate the use and potential of in situ XRD are made. It is not intended to be a review of the art but a highlight of the challenges which the catalytic and material scientists face when entering the avenue. (Author)

  9. Use of agar agar stabilized milled zero-valent iron particles for in situ groundwater remediation

    Science.gov (United States)

    Schmid, Doris; Velimirovi?, Milica; Wagner, Stephan; Mici? Batka, Vesna; von der Kammer, Frank; Hofmann, Thilo

    2015-04-01

    A major obstacle for use of nanoscale zero-valent iron (nZVI) particles as a nontoxic material for effective in situ degradation of chlorinated aliphatic hydrocarbons (CAHs) is the high production cost. For that reason, submicro-scale milled zero-valent iron particles were recently developed (milled ZVI, UVR-FIA, Germany) by grinding macroscopic raw materials of elementary iron as a cheaper alternative to products produced by solid-state reduction. However, milled ZVI particles tend to aggregate and due to the rather large particle size (d50= 11.9 µm) also rapidly sediment. To prevent aggregation and consequently sedimentation of milled ZVI particles and therefore improve the mobility after in situ application, the use of a stabilizer is considered in literature as a most promising option. In this study, milled ZVI particles (1 g L-1 of particle concentration) were stabilized by environmentally friendly polymer agar agar (>0.5 g L-1), which had a positive impact on the milled ZVI stability. Sedimentation rate was significantly decreased by increasing the suspension viscosity. Column transport experiments were performed for bare and agar agar stabilized milled ZVI particles in commercially available fine grained quartz sand (DORSILIT® Nr.8, Gebrüder Dorfner GmbH Co, Germany) and different porous media collected from brownfields. The experiments were carried out under field relevant injection conditions of 100 m d-1. The maximal travel distance (LT) of less than 10 cm was determined for non-stabilized suspension in fine grained quartz sand, while agar agar (1 g L-1) stabilized milled ZVI suspension revealed LT of 12 m. Similar results were observed for porous media from brownfields showing that mobility of agar agar stabilized particle suspensions was significantly improved compared to bare particles. Based on the mobility data, agar agar stabilized milled zero-valent iron particles could be used for in situ application. Finally, lab-scale batch degradation experiments were performed to determine the impact of agar agar on the reactivity of milled ZVI and investigate the apparent corrosion rate of particles by quantifying the hydrogen gas generated by anaerobic corrosion of milled ZVI. The results indicate that agar agar had a positive impact on the milled ZVI stability and mobility, however adverse impact on the reactivity towards trichloroethene (TCE) was observed compared to the non-stabilized material. On the other hand, this study shows that the apparent corrosion rate of non-stabilized and agar agar stabilized milled ZVI particles is in the same order of magnitude. These data indicate that the dechlorination pathway of TCE by agar agar stabilized milled ZVI particles is possibly impacted by blocking of the reactive sites and not hydrogen revealed during particles corrosion. Finally, calculated longevity of the particles based on the apparent corrosion rate is significantly prolonged compared to the longevity of the nZVI particles reported in previous studies. This research receives funding from the European Union's Seventh Framework Programme FP7/2007-2013 under grant agreement n°309517.

  10. Straightforward technique for in situ imaging of spin-coated thin films

    Science.gov (United States)

    Toolan, Daniel T. W.

    2015-02-01

    Spin-coating provides a facile method for the production of highly uniform thin films that have applications as photoresists, coatings, and in organic electronics. Due to the rapid high-speed nature of spin-coating, obtaining data in situ has proved problematic. Recently, a number of in situ characterization techniques have provided new insights into the processes occurring during spin-coating. This paper demonstrates a straightforward method for obtaining in situ optical reflectance images during spin-coating that provide insights into film thinning dynamics, the origins of surface inhomogeneities caused by contaminated substrates, and crystallization processes. This technique could be easily implemented industrially and in many laboratories and will allow for a better understanding of the spin-coating process.

  11. Does the in situ technique improve flow characteristics in femoropopliteal bypass?

    Science.gov (United States)

    Gannon, M X; Simms, M H; Goldman, M

    1986-12-01

    A postulated advantage of in situ over reversed vein bypass is improved flow characteristics. This study compares Doppler frequency analyses in 22 patients with reversed veins and in 21 patients with in situ femoropopliteal vein grafts. Signals from the common femoral artery, the femoral anastomosis, and the vein in the mid thigh were analyzed and the pulsatility index (PI) and flow disturbance index (FDI) calculated (FDI = maximum frequency divided by median frequency). The two groups were similar clinically and common femoral artery PI showed inflow to be similar and satisfactory. Marked turbulence occurred at the femoral anastomosis where peak FDI rose from 1.67 +/- 0.19 (mean +/- SD) to 2.96 +/- 0.69 in the in situ vein group and from 1.74 +/- 0.51 to 3.11 +/- 0.64 in the reversed vein group (p less than 0.001). This turbulence was much reduced at mid thigh level where peak FDI had fallen to 1.45 +/- 0.17 in the reversed vein group and 1.51 +/- 0.23 in the in situ vein group (p less than 0.001). Comparison of the signals from the femoral anastomosis and from the vein at mid thigh showed that the amount of flow disturbance was no different in the in situ vein group from that in the reversed vein group (unpaired t test). In this study flow patterns were not improved by use of the in situ bypass technique. PMID:3537343

  12. Localized in-situ polymerization on graphene surfaces for stabilized graphene dispersions

    OpenAIRE

    Das, Sriya; Wajid, Ahmed S.; Shelburne, John L.; Liao, Yen-Chi; Green, Micah J.

    2010-01-01

    We demonstrate a novel in situ polymerization technique to develop localized polymer coatings on the surface of dispersed pristine graphene sheets. Graphene sheets show great promise as strong, conductive fillers in polymer nanocomposites; however, difficulties in dispersion quality and interfacial strength between filler and matrix have been a persistent problem for graphene-based nanocomposites, particularly for pristine graphene. To address this problem, a physisorbed pol...

  13. A novel in-situ sampling and VFA sensor technique for anaerobic systems

    OpenAIRE

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær

    2006-01-01

    A key information for understanding and controlling the anaerobic biogas process is the concentration of Volatile Fatty Acids (VFA). However, access to this information has so far been limited to off-line measurements by manual time and labour consuming methods. We have developed a new technique that has made it possible to monitor VFA on-line in one of the most difficult media: animal slurry or manure. A novel in-situ filtration technique has made it possible to perform microfilt...

  14. Switchable pickering emulsions stabilized by silica nanoparticles hydrophobized in situ with a conventional cationic surfactant.

    Science.gov (United States)

    Zhu, Yue; Jiang, Jianzhong; Liu, Kaihong; Cui, Zhenggang; Binks, Bernard P

    2015-03-24

    A stable oil-in-water Pickering emulsion stabilized by negatively charged silica nanoparticles hydrophobized in situ with a trace amount of a conventional cationic surfactant can be rendered unstable on addition of an equimolar amount of an anionic surfactant. The emulsion can be subsequently restabilized by adding a similar trace amount of cationic surfactant along with rehomogenization. This destabilization-stabilization behavior can be cycled many times, demonstrating that the Pickering emulsion is switchable. The trigger is the stronger electrostatic interaction between the oppositely charged ionic surfactants compared with that between the cationic surfactant and the (initially) negatively charged particle surfaces. The cationic surfactant prefers to form ion pairs with the added anionic surfactant and thus desorbs from particle surfaces rendering them surface-inactive. This access to switchable Pickering emulsions is easier than those employing switchable surfactants, polymers, or surface-active particles, avoiding both the complicated synthesis and the stringent switching conditions. PMID:25736518

  15. Application of optical techniques for in situ analysis of plasma facing carbon tiles

    Science.gov (United States)

    Nakazato, H.; Yoshida, M.; Tanabe, T.; Masaki, K.; Miya, N.; Sato, M.

    2009-06-01

    Optical absorption/emission spectroscopy is considered to be used for in situ characterization of plasma facing carbon tiles and quantitative evaluation of tritium. In this paper we have applied ex situ laser Raman spectroscopy for carbon tiles used as first wall and divertor in JT-60 exposed to HH discharge plasma to verify the applicability of the technique. The analysis shows that the micro-structure of the carbon tile surfaces is modified in a similar way like damaging by energetic ion irradiation and that one can get information of how graphite structures are damaged by plasma exposure or what kind of structures the redeposited carbon obtains.

  16. Instrumentation for in situ coal gasification: an assessment of techniques evaluated on the Hanna II experiment

    Energy Technology Data Exchange (ETDEWEB)

    Northrop, D.A.; Beard, S.G.; Bartel, L.C.; Beckham, L.W.; Hommert, P.J.

    1977-09-01

    The Hanna II in-situ coal gasification experiment was conducted by the Laramie Energy Research Center during 1975 to 76. Sandia Laboratories designed, fielded, and evaluated variations of seven instrumentation techniques belonging to two general classes: (a) diagnostic techniques (thermal, in-seam gas sampling and pressure, and overburden tilt and displacement) to obtain data for process characterization and (b) remote monitoring techniques (electrical, passive acoustic, and induced seismic) being developed to provide a continuous, real-time map of the in-situ process for application in a process control system. Assessments of these techniques have been made with respect to feasibility, information obtainable, and possible future development and applications. In general, very positive assessments were obtained. Extensive thermocouple arrays, which incorporated special branched circuitry for data validation, provided the most detailed characterization of in-situ coal gasification yet obtained. The feasibility of in-seam gas sampling and pressure measurements was demonstrated and composition changes due to the advancing reaction front were detailed. The thermocouple circuits and gas sampling and pressure canisters are part of a diagnostic well specification now under development for general in-situ applications. Promising results were obtained for two remote monitoring techniques. Direct excitation electrical potential and a modified Schlumberger technique. Contour maps of potential data from a surface array showed the location and movement of the reaction at 300 ft depth. Mapping the source of process-related acoustic signals was shown to be feasible. Borehole-to-borehole induced seismic techniques were able to delineate the advance of the gasification process.

  17. In situ observation of defect growth beyond the irradiated region in yttria-stabilized zirconia induced by 400 keV xenon ion-beam at -90 and 30 degrees C

    International Nuclear Information System (INIS)

    Single crystals of yttria-stabilized zirconia were irradiated with 400 keV Xe ion-beam at room temperature and minus 90 degrees centigrade. Defect growth was monitored in situ with Rutherford Backscattering and ion channeling techniques using a 2 MeV He ion beam

  18. Laser Based In Situ Techniques: Novel Methods for Generating Extreme Conditions in TEM Samples

    Energy Technology Data Exchange (ETDEWEB)

    Taheri, M; Lagrange, T; Reed, B; Armstrong, M; Campbell, G; DeHope, W; Kim, J; King, W; Masiel, D; Browning, N

    2008-02-25

    The Dynamic Transmission Electron Microscope (DTEM) is introduced as a novel tool for in situ processing of materials. Examples of various types of dynamic studies outline the advantages and differences of laser-based heating in the DTEM in comparison to conventional (resistive) heating in situ TEM methods. We demonstrate various unique capabilities of the drive laser, namely, in situ processing of nanoscale materials, rapid and high temperature phase transformations, and controlled thermal activation of materials. These experiments would otherwise be impossible without the use of the DTEM drive laser. Thus, the potential of the DTEM to as a new technique to process and characterize the growth of a myriad of micro and nanostructures is demonstrated.

  19. Blast furnace slag-modified grouts for in situ stabilization of chromium-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Allan, M.L.; Kukacka, L.E. [Brookhaven National Lab., Upton, NY (United States)

    1995-12-01

    Blast furnace slag-modified grouts were used to stabilize soils contaminated with trivalent and hexavalent chromium. Slag content, grout/soil ratio and water/cementitious material ratio were varied to determine the effects on leachability of chromium, permeability and compressive strength. Slag-modified grouts successfully stabilized Cr(VI)-contaminated soil to give low leachability, thereby allowing omission of the pretreatment stage to reduce Cr(VI) to Cr(III) necessary with lime and ordinary Portland cement stabilization procedures. Leachability of both Cr(III) and Cr(VI) decreased with increasing slag content. The permanence of leach resistance is enhanced by higher slag levels in grout. Compressive strength of grout-treated soil ranges from 6 to 36 MPa and permeability is of the order of 10{sup {minus}11} to 10{sup {minus}7} cm/s, depending on mix proportions. Slag-modified grouts have potential for in situ stabilization of Cr(III)- or Cr(VI)-contaminated landfills.

  20. New techniques for in-situ observations of crack growth behaviour

    OpenAIRE

    Marrow, TJ

    2008-01-01

    Experimental observations are essential for the validation for models for crack growth behaviour, particularly in the short crack regime. This paper reports the use of several new methods applied to in-situ short crack observation, including 3D observations of microstructure and cracking by synchrotron tomography techniques, and 2D optical digital image correlation. The examples presented include stress corrosion of stainless steels in aqueous environments, and brittle fracture of of nuclear ...

  1. Cyanea capillata Bell Kinematics Analysis through Corrected In Situ Imaging and Modeling Using Strategic Discretization Techniques

    OpenAIRE

    Villanueva, Alex A.; Priya, Shashank

    2014-01-01

    Obtaining accurate kinematic data of animals is essential for many biological studies and bio-inspired engineering. Many animals, however, are either too large or too delicate to transport to controlled environments where accurate kinematic data can be easily obtained. Often, in situ recordings are the only means available but are often subject to multi-axis motion and relative magnification changes with time leading to large discrepancies in the animal kinematics. Techniques to compensate fo...

  2. Detection of chromosome aberrations in interphase nuclei using fluorescence in situ hybridization technique.

    OpenAIRE

    Song, H. G.; Choi, S. O.; Kang, I. B.

    1993-01-01

    We report here several experiences of interphase cytogenetics, using fluorescence in situ hybridization (FISH) technique, for the detection of chromosome aberrations. FISH, using alpha satellite specific probes of 18, X, Y chromosomes, was done in interphase nuclei from peripheral blood of patients with Edwards' syndrome, Klinefelter's syndrome and Turner's syndrome with healthy male and female controls, respectively. The distributions of fluorescent signals in 100 interphase nuclei were well...

  3. On the stability of a variety of organic photovoltaic devices by IPCE and in situ IPCE analyses – the ISOS-3 inter-laboratory collaboration

    DEFF Research Database (Denmark)

    Teran-Escobar, Gerardo; Tanenbaum, David

    2012-01-01

    This work is part of the inter-laboratory collaboration to study the stability of seven distinct sets of state-of-the-art organic photovoltaic (OPV) devices prepared by leading research laboratories. All devices have been shipped to and degraded at RISØ-DTU up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. In this work, we apply the Incident Photon-to-Electron Conversion Efficiency (IPCE) and the in situ IPCE techniques to determine the relation between solar cell performance and solar cell stability. Different ageing conditions were considered: accelerated full sun simulation, low level indoor fluorescent lighting and dark storage. The devices were also monitored under conditions of ambient and inert (N2) atmospheres, which allows for the identification of the solar cell materials more susceptible to degradation by ambient air (oxygen and moisture). The different OPVs configurations permitted the study of the intrinsic stability of the devices depending on: two different ITO-replacement alternatives, two different hole extraction layers (PEDOT:PSS and MoO3), and two different P3HT-based polymers. The response of un-encapsulated devices to ambient atmosphere offered insight into the importance of moisture in solar cell performance. Our results demonstrate that the IPCE and the in situ IPCE techniques are valuable analytical methods to understand device degradation and solar cell lifetime.

  4. Grout performance in support of in situ stabilization/solidification of the GAAT tank sludges

    International Nuclear Information System (INIS)

    The Gunite trademark and associated tanks (GAATs) were constructed at ORNL between 1943 and 1951 and were used for many years to collect radioactive and chemical wastes. These tanks are currently inactive. Varying amounts of the sludge were removed and disposed of through the Hydrofracture Program. Thus, some tanks are virtually empty, while others still contain significant amounts of sludge and supernatant. In situ grouting of the sludges in the tanks using multi-point injection (MPI trademark), a patented, proprietary technique, is being investigated as a low-cost alternative to (1) moving the sludges to the Melton Valley Storage Tanks (MVSTs) for later solidification and disposal, (2) ex situ grouting of the sludges followed by either disposal back in the tanks or containerizing and disposal elsewhere, and (3) vitrification of the sludges. The paper discusses the chemical characteristics of the GAATs and the type of chemical surrogate that was used during the leachability tests. This is followed by the experimental work, which, consisted of scope testing and sensitivity testing. The scope testing explored the rheology of the proposed jetting slurries and the settling properties of the proposed grouts using sand-water mixes for the wet sludge. After establishing a jetting slurry and grout with an acceptable rheology and settling properties, the proposed in situ grout formulation was subjected to sensitivity testing for variations in the formulation

  5. Nuclear in-situ analysis techniques for the mineral and energy resources mining industries

    International Nuclear Information System (INIS)

    The technology for in-situ analysis based on nuclear techniques, such as borehole logging and surface analysis, is now utilised by the energy and metalliferous mining industry. The techniques developed by CSIRO are spectrometric. This uniquely provides opportunity for implementing analysis techniques which are direct instead of being based on the measurement of surrogates. Thus, the techniques lead to quantitative assays, which are available on-line, which provides mining-technology users with increased flexibility in scheduling operations to achieve improved productivity. The paper reviews in detail the performance of the various CSIRO techniques (and the consequent licensed SIROLOG technology) in current routine application such as deposits of black and brown coals and iron ore. It also briefly discussed the potential for logging applications in the nickel, manganese, copper and lead-zinc mining industries. New relevant developments, namely the ultra-low activity probes and face analysers, are also presented. 14 refs., 1 tab., 5 figs

  6. Dynamic Probing of Nanoparticle Stability In Vivo: A Liposomal Model Assessed Using In Situ Microdialysis and Optical Imaging

    International Nuclear Information System (INIS)

    Nanoparticle-mediated drug delivery and controlled release has been a vigorous research area in contemporary nano medicine. The in vivo stability of nanoparticle delivered on site is a prerequisite for the design of drug-controlled release by any means. In this study, the first methodology comprised of microdialysis and optical imaging to assess the liposome stability in vivo is reported. Macroscopically, we demonstrated the DPPG liposomes with negative surface charge fast accumulated in the rat liver upon their i.v. administration using optical imaging. Microscopically, the concurrent analysis of fluorescent molecules leaching from the liposomes, in situ sampled using microdialysis probe, provides the dynamic information of stability of DPPG liposomes locus in quo. The current combination of in situ microdialysis and optical imaging possesses a great potential for use as a platform technology to evaluate the nanoparticle stability and the bioavailability of drug payload released on targeted site in vivo.

  7. Techniques for the stabilization and assessment of treated copper-, chromium-, and arsenic-contaminated soil.

    Science.gov (United States)

    Maurice, Christian; Lidelöw, Sofia; Gustavsson, Björn; Lättström, Anders; Ragnvaldsson, Daniel; Leffler, Per; Lövgren, Lars; Tesfalidet, Solomon; Kumpiene, Jurate

    2007-09-01

    Remediation mainly based on excavation and burial of the contaminated soil is impractical with regard to the large numbers of sites identified as being in need of remediation. Therefore, alternative methods are needed for brownfield remediation. This study was conducted to assess a chemical stabilization procedure of CCA-contaminated soil using iron (Fe)-containing blaster sand (BS) or oxygen-scarfing granulate (OSG). The stabilization technique was assessed with regard to the feasibility of mixing ameliorants at an industrial scale and the efficiency of the stabilization under different redox conditions. The stability was investigated under natural conditions in 1-m3 lysimeters in a field experiment, and the effect of redox conditions was assessed in a laboratory experiment (10 L). The treatments with high additions of ameliorant (8% and 17%) were more successful in both the laboratory and field experiments, even though there was enough Fe on a stochiometric basis even at the lowest addition rates (0.1% and 1%). The particle size of the Fe and the mixing influenced the stabilization efficiency. The development of anaerobic conditions, simulated by water saturation, increases the fraction of arsenic (AsIII) and, consequently, As mobility. The use of high concentrations of OSG under aerobic conditions increased the concentrations of nickel (Ni) and copper (Cu) in the pore water. However, under anaerobic conditions, it decreased the As leaching compared with the untreated soil, and Ni and Cu leaching was not critical. The final destination of the treated soil should govern the amendment choice, that is, an OSG concentration of approximately 10% may be suitable if the soil is to be landfilled under anaerobic conditions. Alternatively, the soil mixed with 1% BS could be kept under aerobic conditions in a landfill cover or in situ at a brownfield site. In addition, the treatment with BS appeared to produce better effects in the long term than treatment with OSG. PMID:17985696

  8. Robust Digital Image Stabilization Technique for Car Camera

    Directory of Open Access Journals (Sweden)

    Yuefei Zhang

    2011-01-01

    Full Text Available This research studies the digital image stabilization technique for the In-Car videos which are acquired from a car camera. Firstly, the relationship is established between the lane-line positions in a camera coordinate and an image plane. Then an analysis is performed to reveal the positions of the lane-lines in In-Car videos. Next, a digital image stabilization method for car cameras is proposed based on lane-line matching. This method begins with extracting the lane-lines from an In-Car video. Then, feature triangles are constructed to estimate the global inter-frame motions of the input video and a series of compensating motion vectors are yielded by using Kalman filter based algorithm with the inter-frame motions. Finally, repositioning the frames of the input video, according to the compensating motion vectors, can produce a stabilized In-Car video. The proposed method is resistant to the scene changes of In-Car videos. The experimental results, both for the simulated In-Car videos and the real ones, have demonstrated that the proposed method can robustly reduce the effects of undesired car camera motions on In-Car videos.

  9. Synthesis of superhydrophobic silica nanofibrous membranes with robust thermal stability and flexibility via in situ polymerization

    Science.gov (United States)

    Yang, Liping; Raza, Aikifa; Si, Yang; Mao, Xue; Shang, Yanwei; Ding, Bin; Yu, Jianyong; Al-Deyab, Salem S.

    2012-09-01

    Superhydrophobic silica nanofibrous membranes exhibiting robust thermal stability and flexibility were prepared by a facile combination of electrospun silica nanofibers and a novel in situ polymerized fluorinated polybenzoxazine (F-PBZ) functional layer that incorporated SiO2 nanoparticles (SiO2 NPs). By using F-PBZ/SiO2 NP modification, the pristine hydrophilic silica nanofibrous membranes were endowed with superhydrophobicity with a water contact angle (WCA) of up to 161°. Surface morphological studies have revealed that the wettability of resultant membranes could be manipulated by tuning the surface composition as well as the hierarchical structures. Quantitative fractal dimension analysis using the N2 adsorption method has confirmed the correlation between hierarchical roughness and WCA for the modified membranes. Furthermore, the as-prepared membranes exhibited high thermal stability (450 °C), good flexibility (0.0127 gf cm), and comparable tensile strength (2.58 MPa), suggesting their use as promising materials for a variety of potential applications in high-temperature filtration, self-cleaning coatings, catalyst carriers, etc., and also provided new insight into the design and development of functional nanofibrous membranes through F-PBZ modification.Superhydrophobic silica nanofibrous membranes exhibiting robust thermal stability and flexibility were prepared by a facile combination of electrospun silica nanofibers and a novel in situ polymerized fluorinated polybenzoxazine (F-PBZ) functional layer that incorporated SiO2 nanoparticles (SiO2 NPs). By using F-PBZ/SiO2 NP modification, the pristine hydrophilic silica nanofibrous membranes were endowed with superhydrophobicity with a water contact angle (WCA) of up to 161°. Surface morphological studies have revealed that the wettability of resultant membranes could be manipulated by tuning the surface composition as well as the hierarchical structures. Quantitative fractal dimension analysis using the N2 adsorption method has confirmed the correlation between hierarchical roughness and WCA for the modified membranes. Furthermore, the as-prepared membranes exhibited high thermal stability (450 °C), good flexibility (0.0127 gf cm), and comparable tensile strength (2.58 MPa), suggesting their use as promising materials for a variety of potential applications in high-temperature filtration, self-cleaning coatings, catalyst carriers, etc., and also provided new insight into the design and development of functional nanofibrous membranes through F-PBZ modification. Electronic supplementary information (ESI) available: Detailed chemical synthesis and structural confirmation of BAF-tfa, FT-IR results, and FE-SEM results. See DOI: 10.1039/c2nr32095a

  10. In situ stabilization of soil lead using phosphorus and manganese oxide: influence of plant growth.

    Science.gov (United States)

    Hettiarachchi, Ganga M; Pierzynski, Gary M

    2002-01-01

    In situ stabilization of Pb contaminated soils can be accomplished by adding P and Mn(IV) oxide. However, the long-term efficacy of in situ stabilization under continual P removal through plant growth is unknown. Moreover, the effects these treatments have on phytoavailability of other metals (Cd and Zn) commonly associated with Pb in soil are not well understood. Greenhouse experiments using sudax [Sorghum vulgare (L.) Moench] and Swiss chard [Beta vulgaris (L.) Koch] were carried out to evaluate the effects of plant growth on soil Pb bioavailability to humans after addition of P and other amendments, and the effects of these treatments on Pb, Cd, and Zn phytoavailability in three metal-contaminated soils. Eight treatments were used: zero P; 2500 mg of P as triple superphosphate (TSP); 5000 mg of P as TSP or phosphate rock (PR); 5000 mg of Mn oxide/kg; and combinations of Mn oxide and P as TSP or PR. The addition of P and/or Mn oxide significantly reduced bioavailable Pb, as measured by the physiologically based extraction test (PBET), in soils compared with the control even after extensive cropping. The PBET data also suggested that removal of P from soluble P sources by plants could negate the beneficial effects of P on bioavailable Pb, unless sufficient soluble P was added or soluble P was combined with Mn oxide. In general, Ph, Cd, and Zn concentrations in shoot tissues of sudax and Swiss chard were reduced significantly by TSP and did not change with the addition of PR. The combination of PR and Mn oxide significantly reduced Pb concentrations in plants compared with the control. PMID:11931448

  11. Concrete - Opalinus clay interaction: in-situ experiment and technique for coring undisturbed interfaces

    International Nuclear Information System (INIS)

    Document available in extended abstract form only. Designs for deep geologic disposal of radioactive waste foresee cementitious materials as structural elements, backfill or waste matrix. Interactions near interfaces are driven by chemical gradients in pore water and resultant diffusive transport, and are predicted to lead to mineralogical alterations in the barrier system, which in turn influences properties like swelling pressure, permeability, or specific retention in case of clay materials. Reactive transport modelling predictions and laboratory and in situ studies revealed significant alteration in both cement and clay-stone. An increase in porosity in the cement close to the interface, and clogging in the clay-stone adjacent to the interface is commonly predicted and observed. The Cement-Clay Interaction (CI) Experiment at the Mont Terri Underground Laboratory (St. Ursanne, Switzerland) aims at demonstrating some of the processes at interfaces to be expected at a realistic spatial scale and under saturated conditions. A duration of 20 years is foreseen during which reaction progress should become measurable and thus comparable to laboratory experiments and modelling predictions. Companion studies address cement hydration, and develop new high-resolution techniques for phase identification using ?-X-ray diffraction at the Paul Scherrer Institut. The field experiment at Mont Terri comprises two vertical boreholes (384 mm diameter, up to 9 m length) in Opalinus Cliameter, up to 9 m length) in Opalinus Clay (OPA) filled with layers of three different concretes and bentonite. The concrete formulations are based on three different binders: Portland cement (OPC), ESDRED cement designed for repository applications (40% of cement substituted by silica fume), and low alkali cement (LAC, containing slag and nano-silica). The characterisation of the three concrete-OPA interfaces after 2 years of alteration are presented in a companion contribution (Jenni et al.). A key issue is the repeat recovery of undisturbed samples of the different interfaces with concrete. A first sampling campaign in 2009 used a simple stabilisation technique with a central anchor rod that was glued in before coring. It was impossible to retrieve completely undisturbed samples. A new technique was developed for the drilling campaign during February 2012, and it was successfully applied in all four sampling boreholes carried out, retrieving a total of 150 kg of core and 10 physically and chemically undisturbed interface samples. The technique comprised intersection drilling at 45 deg. inclination and 220 mm OD to within 50 cm of the vertical concrete pile. The base was reamed planar, and templates were installed to drill a circular arrangement of 6 boreholes with 46 mm OD, three at a time. These small boreholes extended across the entire pile (1.4-1.6 m), and anchor rods made of fibre glass and filled with cement were embedded with epoxy resin. A different template was subsequently used to over-core (131 mm OD / 101 mm core DM, double-barrel, acrylic liner) cutting through the reinforcements. Stabilized composite cores of 1.4-1.6 m length could be retrieved in this manner. (authors)

  12. CASE STUDY: IN-SITU SOLIDIFICATION/STABILIZATION OF HAZARDOUS ACID WASTE OIL SLUDGE AND LESSONS LEARNED

    Science.gov (United States)

    The South 8th Street site contained a 2.5 acre oily sludge pit with very low pH waste produced by oil recycling activities. This sludge was treated using in-situ solidification/stabilization technology applied by deep soil mixing augers. The problems encountered, solutions develo...

  13. Deciphering the thermal behavior of lithium rich cathode material by in situ X-ray diffraction technique

    Science.gov (United States)

    Muhammad, Shoaib; Lee, Sangwoo; Kim, Hyunchul; Yoon, Jeongbae; Jang, Donghyuk; Yoon, Jaegu; Park, Jin-Hwan; Yoon, Won-Sub

    2015-07-01

    Thermal stability is one of the critical requirements for commercial operation of high energy lithium-ion batteries. In this study, we use in situ X-ray diffraction technique to elucidate the thermal degradation mechanism of 0.5Li2MnO3-0.5LiNi0.33Co0.33Mn0.33O2 lithium rich cathode material in the absence and presence of electrolyte to simulate the real life battery conditions and compare its thermal behavior with the commercial LiNi0.33Co0.33Mn0.33O2 cathode material. We show that the thermal induced phase transformations in delithiated lithium rich cathode material are much more intense compared to similar single phase layered cathode material in the presence of electrolyte. The structural changes in both cathode materials with the temperature rise follow different trends in the absence and presence of electrolyte between 25 and 600 °C. Phase transitions are comparatively simple in the absence of electrolyte, the fully charged lithium rich cathode material demonstrates better thermal stability by maintaining its phase till 379 °C, and afterwards spinel structure is formed. In the presence of electrolyte, however, the spinel structure appears at 207 °C, subsequently it transforms to rock salt type cubic phase at 425 °C with additional metallic, metal fluoride, and metal carbonate phases.

  14. New insights into the formation of microporous materials by in situ scattering techniques.

    Science.gov (United States)

    Sankar, Gopinathan; Okubo, Tatsuya; Fan, Wei; Meneau, Florian

    2007-01-01

    The formation of zeolite A (LTA) in the presence of tetramethylammonium cations and CoA1PO-5 (AFI structure) in the presence of tetraethyl ammonium hydroxide was studied using time-resolved, in situ energy dispersive X-ray diffraction (EDXRD) and small angle and wide angle X-ray scattering (SAXS/WAXS) techniques. The in situ SAXS measurements show the formation of homogeneous precursors, ca. 10 nm in size, prior to the crystallization of LTA, and consumed during the crystallization. The crystal size is estimated by fitting the SAXS patterns with an equation for a cubic particle, and it is revealed that the final crystal size of the LTA depends on the synthesis temperature. The crystallisation of CoA1PO-5 occurs through the formation of poly-dispersed particles with an average size of the precursor particle of ca. 50 nm. PMID:17955808

  15. Powder metallurgical nanostructured medium carbon bainitic steel: Kinetics, structure, and in situ thermal stability studies

    International Nuclear Information System (INIS)

    It has been possible to produce incredibly fine plates of bainitic ferrite separated by a percolating network of retained austenite in a medium carbon steel produced by mechanical alloying followed by spark plasma sintering and isothermal heat treatment. This is because the sintering process limits the growth of the austenite grains to such an extent that the martensite-start temperature is suppressed in spite of the medium carbon concentration. Furthermore, the fine austenite grain size accelerates the bainite transformation, which can therefore be suppressed to low temperatures to obtain a nanostructure. Microscopy and in situ synchrotron X-ray diffraction were used to investigate the morphology and the thermal stability of the retained austenite during continuous heating. These latter experiments revealed a gradient of carbon concentration in the retained austenite and a reduced thermal stability in high carbon film-austenite. It was also possible to correlate the evolution of defect density and carbon depletion in both retained austenite and bainitic ferrite during tempering.

  16. Powder metallurgical nanostructured medium carbon bainitic steel: Kinetics, structure, and in situ thermal stability studies

    Energy Technology Data Exchange (ETDEWEB)

    Lonardelli, I., E-mail: il244@cam.ac.uk [University of Cambridge, Materials Science and Metallurgy, Pembroke Street, Cambridge CB2 3QZ (United Kingdom); University of Trento, Materials Engineering and Industrial Technologies, via Mesiano 77, 38123 Trento (Italy); Bortolotti, M. [Fondazione Bruno Kessler, via Sommarive 18, 38123 Trento (Italy); Beek, W. van [Swiss-Norwegian Beamlines, ESRF, BP 220, 38043 Grenoble Cedex (France); Girardini, L.; Zadra, M. [K4-Sint, via Dante 300, 38057 Pergine Valsugana (Italy); Bhadeshia, H.K.D.H. [University of Cambridge, Materials Science and Metallurgy, Pembroke Street, Cambridge CB2 3QZ (United Kingdom)

    2012-10-15

    It has been possible to produce incredibly fine plates of bainitic ferrite separated by a percolating network of retained austenite in a medium carbon steel produced by mechanical alloying followed by spark plasma sintering and isothermal heat treatment. This is because the sintering process limits the growth of the austenite grains to such an extent that the martensite-start temperature is suppressed in spite of the medium carbon concentration. Furthermore, the fine austenite grain size accelerates the bainite transformation, which can therefore be suppressed to low temperatures to obtain a nanostructure. Microscopy and in situ synchrotron X-ray diffraction were used to investigate the morphology and the thermal stability of the retained austenite during continuous heating. These latter experiments revealed a gradient of carbon concentration in the retained austenite and a reduced thermal stability in high carbon film-austenite. It was also possible to correlate the evolution of defect density and carbon depletion in both retained austenite and bainitic ferrite during tempering.

  17. Remote in situ voltammetric techniques to characterize the biogeochemical cycling of trace metals in aquatic systems.

    Science.gov (United States)

    Tercier-Waeber, Mary-Lou; Taillefert, Martial

    2008-01-01

    The contamination of aquatic ecosystems by natural and anthropogenic metals has lead to a need to better characterize their impact in the environment. To a large extent, the fate and the (eco)toxicity of these elements in aquatic systems are related to their chemical speciation, which may vary continuously in space and time. Detailed measurements of the fraction of specific metal species or groups of homologous metal species and their variation as a function of the bio-physicochemical conditions of the natural media are thus of prime importance. To determine these metal fractions as well as redox chemical species regulating their distribution (dissolved oxygen, sulfides, iron and manganese oxides), new analytical tools capable of performing in situ, real-time monitoring in both water columns and sediments with minimum perturbation of the media are required. This paper reviews the challenges associated with metal speciation studies, and the progress made with state of the art voltammetric techniques to measure the speciation of metals in situ. More specifically, it summarizes the specific conceptual, analytical, and technical criteria that must be considered and/or fulfilled to develop rugged, field deployable, non-perturbing sensors and probes. Strategies used to satisfy these criteria are presented by describing the up-to-date most advanced voltammetric sensors, mini-/micro-integrated analytical systems, and submersible equipments developed for in situ measurements of trace metals and main redox species in aquatic systems. The spatial and temporal resolutions achieved by these news tools represent a significant advantage over traditional laboratory techniques, while simultaneously remaining cost effective. The application of these tools to aquatic systems is illustrated by several examples of unattended and remote in situ monitoring and/or profiling in water columns and sediments. PMID:18175016

  18. Screening of premalignant cervical lesions for HPV 16 DNA by sandwich and in situ hybridization techniques.

    Science.gov (United States)

    Parkkinen, S; Syrjänen, S; Syrjänen, K; Yliskoski, M; Tenhunen, J; Mäntyjärvi, R; Ranki, M

    1988-06-01

    A series of 97 cervical smears and 69 directed punch biopsies derived from 84 consecutive women prospectively followed-up for cervical HPV (human papillomavirus) infections were studied using the sandwich hybridization and in situ hybridization techniques with HPV 16 DNA probes. The aim was to test the sensitivity and applicability of these two techniques in routine diagnosis of cervical HPV infections from smears. As a measure of specimen adequacy, the number of cells recovered in the cervical scrape was determined along with HPV 16 DNA in the sandwich hybridization test using human pro-alpha 2(I)-collagen gene probe. CIN (cervical intraepithelial neoplasia) was suggested in 56% of the patients by the Pap smear, and disclosed in 65% of the biopsies. HPV 16 DNA was present in 57% of cervical scrapes consistent with CIN, i.e., were of Pap smear classes III or IV. Forty percent of the scrapes not suggestive of CIN, i.e., Pap smear classes I or II, also contained HPV 16 DNA. The detection rate for HPV 16 DNA of the sandwich hybridization method was 89% of that of the in situ method in adequate scrapes, but only 43% in cell-poor specimens. The number of HPV 16 DNA-positive scrapes as compared with the total number of diagnoses obtained by studying also the biopsies was 31/36 (69 patients). The results indicate that the cervical scrape as a noninvasive specimen is applicable for screening of cervical HPV infections, and it can be studied with acceptable sensitivity by the rapid sandwich hybridization technique. However, if a punch biopsy is indicated it should be studied using the in situ hybridization technique that allows more sensitive detection of HPV DNA than any other hybridization method and enables the analysis of several HPV types in the same sample instead of only one HPV type in the scrapes. PMID:2836276

  19. In situ cDNA polymerase chain reaction. A novel technique for detecting mRNA expression.

    OpenAIRE

    Chen, R H; Fuggle, S. V.

    1993-01-01

    We report a novel method for detecting intracellular messenger RNA by combining the techniques of in situ hybridization and polymerase chain reaction (PCR) (in situ cDNA PCR). The technique could detect low abundancy signals and distinguish different levels of gene expression. We examined the expression of the functional markers of activated cytotoxic T lymphocytes, granzyme A, and perforin in human lymphocytes from in vitro cultures. The amplification products were found in the cells and the...

  20. In situ preparation of fluorescent CdTe quantum dots with small thiols and hyperbranched polymers as co-stabilizers

    OpenAIRE

    Shi, Yunfeng; Ma, Zhimin; Cui, Ningning; Liu, Yanli; Hou, Xiaoyu; Du, Weimin; Liu, Lin; Gangsheng, Tong

    2014-01-01

    A new strategy for in situ preparation of highly fluorescent CdTe quantum dots (QDs) with 3-mercaptopropionic acid (MPA) and hyperbranched poly(amidoamine)s (HPAMAM) as co-stabilizers was proposed in this paper. MPA and HPAMAM were added in turn to coordinate Cd2+. After adding NaHTe and further microwave irradiation, fluorescent CdTe QDs stabilized by MPA and HPAMAM were obtained. Such a strategy avoids the aftertreatment of thiol-stabilized QDs in their bioapplication and provides an opport...

  1. Stabilized in situ rectangular MgB2 wires: the effect of B purity and sheath materials

    International Nuclear Information System (INIS)

    Stabilized four-filament SiC-added in situ MgB2 wires were prepared by the rectangular wire-in-tube (RWIT) technique, using boron powders of different purity (90% and 99%), SiC powders of different agglomerate size and sheaths of different metals. The critical current density at 11 T and 4.2 K improved by 5-10 times by using boron powder of higher purity, SiC powder of small agglomerate size, a chemically inert Ti barrier and mechanical support provided by a Monel sheath. The decrease in critical temperature (Tc) and increase in critical current density (Jc) of wires could be explained in terms of carbon doping. Formation of Mg2Si and B-rich secondary phases, and carbon substitution was studied using EDX chemical mapping in a scanning electron microscope (SEM). The addition of SiC results in the formation of B-rich secondary phases. Our results support the mechanism of carbon doping through the reaction of SiC with Mg to form Mg2Si and release free carbon. However, the extent of effective carbon doping depends on the size of the precursor SiC agglomerates, as large SiC agglomerates are unable to react with Mg. B precursor powder of lower purity and Mg2Si secondary phase formation led to incomplete phase formation of MgB2 and consequently to lowered Jc

  2. Stabilized in situ rectangular MgB2 wires: the effect of B purity and sheath materials

    Science.gov (United States)

    Ková?, P.; Birajdar, B.; Hušek, I.; Holúbek, T.; Eibl, O.

    2008-04-01

    Stabilized four-filament SiC-added in situ MgB2 wires were prepared by the rectangular wire-in-tube (RWIT) technique, using boron powders of different purity (90% and 99%), SiC powders of different agglomerate size and sheaths of different metals. The critical current density at 11 T and 4.2 K improved by 5-10 times by using boron powder of higher purity, SiC powder of small agglomerate size, a chemically inert Ti barrier and mechanical support provided by a Monel sheath. The decrease in critical temperature (Tc) and increase in critical current density (Jc) of wires could be explained in terms of carbon doping. Formation of Mg2Si and B-rich secondary phases, and carbon substitution was studied using EDX chemical mapping in a scanning electron microscope (SEM). The addition of SiC results in the formation of B-rich secondary phases. Our results support the mechanism of carbon doping through the reaction of SiC with Mg to form Mg2Si and release free carbon. However, the extent of effective carbon doping depends on the size of the precursor SiC agglomerates, as large SiC agglomerates are unable to react with Mg. B precursor powder of lower purity and Mg2Si secondary phase formation led to incomplete phase formation of MgB2 and consequently to lowered Jc.

  3. Thermo-stabilized, porous polyimide microspheres prepared from nanosized SiO2 templating via in situ polymerization

    Directory of Open Access Journals (Sweden)

    M. Q. Liu

    2015-01-01

    Full Text Available In this article, we addressed a feasible and versatile method of the fabrication of porous polyimide microspheres presenting excellent heat resistance. The preparation process consisted of two steps. Firstly, a novel polyimide/nano-silica composite microsphere was prepared via the self-assembly structures of poly(amic acid (PAA, precursor of PI/nanosized SiO2 blends after in situ polymerization, following the two-steps imidization. Subsequently, the encapsulated nanoparticles were etched away by hydrofluoric acid treatment, giving rise to the pores. It is found the composite structure of PI/SiO2 is a precondition of the formation of nanoporous structures, furthermore, the morphology of the resultant pore could be relatively tuned by changing the content and initial morphology of silica nano-particles trapped into PI matrix. The thermal properties of the synthesized PI porous spheres were studied, indicating that the introduction of nanopores could not effectively influence the thermal stabilities of PI microspheres. Moreover, the fabrication technique described here may be extended to other porous polymer systems.

  4. Measurement techniques for in situ stresses around underground constructions in a deep clay formation

    Directory of Open Access Journals (Sweden)

    Li X.L.

    2010-06-01

    Full Text Available Disposal in deep underground geological formations is internationally recognized as the most viable option for the long-term management of high-level radioactive waste. In Belgium, the Boom clay formation is extensively studied in this context, in particular at the 225 m deep HADES Underground Research Facility in Mol. A cost-effective design of deep underground structures requires an accurate assessment of the in situ stresses; a good estimation of these stresses is also essential when interpreting in situ experiments regarding the hydro-mechanical behaviour of the host formation. Different measurement techniques are available to provide data on the stress evolution and other mechanical properties of the geological formation. The measurement can be direct (measurement of total pressure, or it can be an indirect technique, deriving the stress from related quantities such as strain (changes in structural members. Most total stress measurements are performed through permanently installed sensors; also once-only measurements are performed through specific methods (e.g. pressuremeter. Direct measurement of the stress state is challenging due to the complex mechanical behaviour of the clay, and the fact that the sensor installation inevitably disturbs the original stress field. This paper describes ways to deal with these problems and presents the results obtained using different techniques at HADES.

  5. Lab scale testing of novel natural analog in situ stabilization agents

    International Nuclear Information System (INIS)

    This report summarizes the laboratory-scale test results on several novel in situ treatment and stabilization agents for buried hazardous and radioactive waste. Paraffin, hematite and phosphate materials were examined when combined with soil and other wastes representative of what might be present at buried waste DOE sites. Hematite was made from the reaction of agricultural iron and lime slurries to form gypsum and iron oxide/hydroxide. Common household paraffin was melted, both with and without a zeolitic additive, waste added and then cooled. Magnesium phosphate was made from the reaction of magnesium oxide and phosphoric acid or potassium biphosphate to form, magnesium phosphate. All were tested with soil and some with additional waste sumulants such as ash, machine oil and nitrate salts. The following laboratory-generated data indicate that all waste encapsulation materials tested are appropriate materials, for field in situ testing. Compressive strengths of treated Idaho National Engineering and Environment Laboratory (INEEL) soil and the waste encapsulation material were sufficient to prevent collapse of the void space in waste, i.e., greater than the NRC 60 psi minimum. The mineralogy and microstructure of hematite was amorphous but should progress to an interlocking crystalline solid. Phosphate was crystalline with characteristics of higher temperature ceramics. Paraffin is non crystalline but encapsulates even very fine grained INEEL soils. Each agent appears to be chemically and physically inert to possible waste materials such as, nitrates and machine cutting oil. Two of the agents hematite and phosphate react favorably with ash increasing the metals retention at higher waste loadings than Portland cement. Hematite, phosphate and zeolite decrease leaching of most hazardous metals from waste when compared to untreated waste and soil. Solution pH, time for reaction initiation, and viscosity values are conducive to jet-grouting application

  6. Lab scale testing of novel natural analog in situ stabilization agents

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, P. [Lockheed Martin Idaho Technology Co., Idaho Falls, ID (United States)

    1997-12-31

    This report summarizes the laboratory-scale test results on several novel in situ treatment and stabilization agents for buried hazardous and radioactive waste. Paraffin, hematite and phosphate materials were examined when combined with soil and other wastes representative of what might be present at buried waste DOE sites. Hematite was made from the reaction of agricultural iron and lime slurries to form gypsum and iron oxide/hydroxide. Common household paraffin was melted, both with and without a zeolitic additive, waste added and then cooled. Magnesium phosphate was made from the reaction of magnesium oxide and phosphoric acid or potassium biphosphate to form, magnesium phosphate. All were tested with soil and some with additional waste sumulants such as ash, machine oil and nitrate salts. The following laboratory-generated data indicate that all waste encapsulation materials tested are appropriate materials, for field in situ testing. Compressive strengths of treated Idaho National Engineering and Environment Laboratory (INEEL) soil and the waste encapsulation material were sufficient to prevent collapse of the void space in waste, i.e., greater than the NRC 60 psi minimum. The mineralogy and microstructure of hematite was amorphous but should progress to an interlocking crystalline solid. Phosphate was crystalline with characteristics of higher temperature ceramics. Paraffin is non crystalline but encapsulates even very fine grained INEEL soils. Each agent appears to be chemically and physically inert to possible waste materials such as, nitrates and machine cutting oil. Two of the agents hematite and phosphate react favorably with ash increasing the metals retention at higher waste loadings than Portland cement. Hematite, phosphate and zeolite decrease leaching of most hazardous metals from waste when compared to untreated waste and soil. Solution pH, time for reaction initiation, and viscosity values are conducive to jet-grouting application.

  7. Efficiency of in situ hybridization as a function of probe size and fixation technique

    International Nuclear Information System (INIS)

    In an attempt to improve fixation technique for viral RNA detection by in situ hybridization, the authors have quantitatively compared the hybridization signal obtained when measles virus or visna virus infected cell cultures were fixed with eight different fixatives and hybridized with 35S-labeled virus-complementary DNA probes of several size ranges. The highest signals were obtained with periodate-lysine-paraformaldehyde-glutaraldehyde (PLPG) fixed cells hybridized with small probes, and were 1.5- to 6.7-fold greater than those obtained with the commonly used fixative acetic ethanol. PLPG and other glutaraldehyde based fixatives also greatly improved the preservation of cellular morphology compared to acetic ethanol. (Auth.)

  8. In Situ Synchrotron X-Ray Techniques for the Study of Lithium Battery Materials

    International Nuclear Information System (INIS)

    The combination of in situ X-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) is a very powerful technique in the study of lithium battery cathode materials. XRD identifies the phase changes that occur during cycling and XAS gives information on the redox charge compensation processes that occur on the transition metal oxides. Because of its element specific nature XAS can identify the occurrence of redox processes on the various cations in doped oxide cathode materials. Since XAS probes short range order and is particularly useful in the study of amorphous tin based composite oxide anode materials

  9. In situ tagging technique for fishes provides insight into growth and movement of invasive lionfish.

    Science.gov (United States)

    Akins, John L; Morris, James A; Green, Stephanie J

    2014-10-01

    Information on fish movement and growth is primarily obtained through the marking and tracking of individuals with external tags, which are usually affixed to anesthetized individuals at the surface. However, the quantity and quality of data obtained by this method is often limited by small sample sizes owing to the time associated with the tagging process, high rates of tagging-related mortality, and displacement of tagged individuals from the initial capture location. To address these issues, we describe a technique for applying external streamer and dart tags in situ, which uses SCUBA divers to capture and tag individual fish on the sea floor without the use of anesthetic. We demonstrate this method for Indo-Pacific lionfish (Pterois volitans/P. miles), species which are particularly vulnerable to barotrauma when transported to and handled at the surface. To test our method, we tagged 161 individuals inhabiting 26 coral reef locations in the Bahamas over a period of 3 years. Our method resulted in no instances of barotrauma, reduced handling and recovery time, and minimal post-tagging release displacement compared with conventional ex situ tag application. Opportunistic resighting and recapture of tagged individuals reveals that lionfish exhibit highly variable site fidelity, movement patterns, and growth rates on invaded coral reef habitats. In total, 24% of lionfish were resighted between 29 and 188 days after tagging. Of these, 90% were located at the site of capture, while the remaining individuals were resighted between 200 m and 1.1 km from initial site of capture over 29 days later. In situ growth rates ranged between 0.1 and 0.6 mm/day. While individuals tagged with streamer tags posted slower growth rates with increasing size, as expected, there was no relationship between growth rate and fish size for individuals marked with dart tags, potentially because of large effects of tag presence on the activities of small bodied lionfish (i.e., tag was up to 7.6% of the lionfish's mass. Our study offers a novel in situ tagging technique that can be used to provide critical information on fish site fidelity, movement patterns, and growth in cases where ex situ tagging is not feasible. PMID:25614791

  10. New application technology for 'in situ' pipeline protection using pigging techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pretorius, Louis Charles [Corrocoat SA (PTY) Ltd., Durban (South Africa)

    2005-07-01

    Pigging of long pipelines is a technique for in situ (field) coating, creating seamless internal structural linings. Originally developed for cleaning pipes, the system was adapted to apply internal anti-corrosion protection to pipes using a thin epoxy layer, which had some problems in weld coverage, stress cracking, poor cold weather curing and the inability to fill pitting corrosion metal loss. New coating materials, revised application methods and modified pigging equipment have made it possible to apply in situ liquid film coatings up to 1 mm thick, as an internal corrosion barrier to pipes, in a single application (similar to continuous screeding) resulting in a bonded 'GRP pipe within a steel pipe'. The method can be used for new projects on fully welded pipe lines avoiding coating problems associated with flange joints and/or couplings, or for refurbishment of old pipelines, varying from 150-900 mm diameter, up to 12 km long. Pipes can be buried, submerged, continuously welded or flanged. Many different pipes, such as oil platform to shore based pipelines, can all be treated using this method. Thick film polymer pigging techniques create new possibilities for Engineers to extend the life of pipeline systems, with significant cost savings compared to replacement pipe. (author)

  11. In situ polymerase chain reaction technique revealed by flow cytometry as a tool for gene detection.

    Science.gov (United States)

    Gibellini, D; Zauli, G; Re, M C; Furlini, G; Lolli, S; Bassini, A; Celeghini, C; La Placa, M

    1995-07-01

    We report a methodology for detecting specific DNA sequences directly inside cells, combining in situ PCR and flow cytometry. This technique is based on in situ PCR performed in the presence of digoxigenin-labeled dUTP to obtain a digoxigenin-labeled amplicon, which is then revealed by an anti-digoxigenin polyclonal antibody directly conjugated to fluorescein. Fluorescence intensity is next evaluated by flow cytometry. Our experimental models were represented by the lymphoblastoid cell lines 8E5LAV, carrying an integrated HIV-1 DNA proviral copy per cell, and A.301, infected in vitro with HIV-1 (strain IIIB). The technique is described in detail with particular attention to the optimization of critical fixation and permeabilization steps. This method allows not only the detection but also an accurate quantification of the number of positive cells in a background of negative cells. Moreover, it has the potentiality to develop into a multiparametric method for the simultaneous study of specific DNA or RNA sequences and surface or intracellular markers. PMID:8572303

  12. Development of Advanced In-Situ Techniques for Chemistry Monitoring and Corrosion Mitigation in SCWO Environments

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, D. D.; Lvov, S. N.

    2000-03-31

    This project is developing sensing technologies and corrosion monitoring techniques for use in super critical water oxidation (SCWO) systems to reduce the volume of mixed low-level nuclear waste by oxidizing organic components in a closed cycle system where CO2 and other gaseous oxides are produced, leaving the radioactive elements concentrated in ash. The technique uses water at supercritical temperatures under highly oxidized conditions by maintaining a high fugacity of molecular oxygen in the system, which causes high corrosion rates of even the most corrosive resistant reactor materials. This project significantly addresses the high corrosion shortcoming through development of (a) advanced electrodes and sensors for in situ potentiometric monitoring of pH in high subcritical and supercritical aqueous solutions, (b) an approach for evaluating the association constants for 1-1 aqueous electrolytes using a flow-through electrochemical thermocell; (c) an electrochemical noise sensor for the in situ measurement of corrosion rate in subcritical and supercritical aqueous systems; (d) a model for estimating the effect of pressure on reaction rates, including corrosion reactions, in high subcritical and supercritical aqueous systems. The project achieved all objectives, except for installing some of the sensors into a fully operating SCWO system.

  13. Technique for in situ measurement of free spectral range and transverse mode spacing of optical cavities.

    Science.gov (United States)

    Stochino, Alberto; Arai, Koji; Adhikari, Rana X

    2012-09-20

    Length and g-factor are fundamental parameters that characterize optical cavities. We developed a technique to measure these parameters in situ by determining the frequency spacing between the resonances of fundamental and spatial modes of an optical cavity. Two laser beams are injected into the cavity, and their relative frequency is scanned by a phase-lock loop, while the cavity is locked to either laser. The measurement of the amplitude of their beat note in transmission reveals the resonances of the longitudinal and the transverse modes of the cavity and their spacing. This method proves particularly useful to characterize complex optical systems, including very long and/or coupled optical cavities, as in gravitational-wave interferometers. This technique and the results of its application to the coupled cavities of a 40 m-long gravitational-wave interferometer prototype are presented here. PMID:23033027

  14. Field application of innovative grouting agents for in situ stabilization of buried waste sites

    Energy Technology Data Exchange (ETDEWEB)

    Loomis, G.G.; Farnsworth, R.K. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1997-12-31

    This paper presents field applications for two innovative grouting agents that were used to in situ stabilize buried waste sites, via jet grouting. The two grouting agents include paraffin and a proprietary iron oxide based cement grout called TECT. These materials were tested in specially designed cold test pits that simulate buried transuranic waste at the Idaho National Engineering Laboratory (INEL). The field demonstrations were performed at the INEL in an area referred to as the Cold Test Pit, which is adjacent to the INEL Radioactive Waste Management Complex (RWMC). At the RWMC, 56,000 m{sup 3} of transuranic (TRU) waste is co-mingled with over 170,000 m{sup 3} of soil in shallow land burial. Improving the confinement of this waste is one of the options for final disposition of this waste. Using jet-grouting technology to inject these materials into the pore spaces of buried waste sites results in the creation of buried monolithic waste forms that simultaneously protect the waste from subsidence, while eliminating the migratory potential of hazardous and radioactive contaminants in the waste.

  15. Field application of innovative grouting agents for in situ stabilization of buried waste sites

    International Nuclear Information System (INIS)

    This paper presents field applications for two innovative grouting agents that were used to in situ stabilize buried waste sites, via jet grouting. The two grouting agents include paraffin and a proprietary iron oxide based cement grout called TECT. These materials were tested in specially designed cold test pits that simulate buried transuranic waste at the Idaho National Engineering Laboratory (INEL). The field demonstrations were performed at the INEL in an area referred to as the Cold Test Pit, which is adjacent to the INEL Radioactive Waste Management Complex (RWMC). At the RWMC, 56,000 m3 of transuranic (TRU) waste is co-mingled with over 170,000 m3 of soil in shallow land burial. Improving the confinement of this waste is one of the options for final disposition of this waste. Using jet-grouting technology to inject these materials into the pore spaces of buried waste sites results in the creation of buried monolithic waste forms that simultaneously protect the waste from subsidence, while eliminating the migratory potential of hazardous and radioactive contaminants in the waste

  16. In situ vitrification demonstration for the stabilization of buried wastes at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    A demonstration of In Situ Vitrification (ISV) technology for the stabilization of radioactively contaminated soil sites at the Oak Ridge National Laboratory (ORNL) was successfully completed during July 1987. This demonstration is the first application of the ISV process not performed at the Hanford Site, where the technology was developed. The joint ORNL-PNL pilot-scale demonstration was performed on a 3/8-scale trench (2 m deep x 1 m wide x 10 m long) that was constructed to simulate a typical seepage trench used for liquid low-level radioactive waste disposal at ORNL from 1951 to 1966. In the ISV process, electrodes are inserted around a volume of contaminated soil, power is applied to the electrodes, and the entire mass is melted from the surface of the soil down through the contaminated zone, thus making a glassy-to-microcrystalline waste form that incorporates the contaminants. Gases produced during the melting are collected, treated, monitored, and released through an off-gas process trailer. In the ORNL demonstration, a 25-t mass of melted rock approximately 1.2 m thick x 2.1 m wide x 4.9 m long was formed during 110 h of operation that consumed approximately 29 MWh of power. Data obtained on the operational performance of the test and waste-form durability will be used to assess the feasibility of applying the ISV technology to an actual waste trench

  17. Improved thermal stability of exchange bias of Mn-Ir/Co-Fe bilayers by novel in situ thermal annealing procedure

    International Nuclear Information System (INIS)

    The effect of in situ thermal annealing of Mn-Ir films under ultra-high vacuum on the metallurgical microstructure and on the thermal stability of the unidirectional anisotropy constant, JK, was investigated for Mn73Ir27/Co70Fe30 bilayers. As a result, we found that the average lateral grain size of Mn-Ir increases with increasing the in situ annealing temperature, TIR and that the shape of JK-T curve changes to convex with increasing the TIR, implying a narrowing distribution of local blocking temperature. We conclude that ultra-high vacuum annealing is effective in improving the thermal stability of the exchange anisotropy of Mn-Ir/Co-Fe bilayers through the change of lateral grain size distribution of the Mn-Ir layer

  18. Computational techniques for voltage stability assessment and control

    CERN Document Server

    Ajjarapu, Venkataramana

    2007-01-01

    Presenting the continuation and bifurcation-based approaches to assess power system voltage stability, this manual provides definitions related to voltage stability based on IEEE/CIGRE voltage stability classification. It presents a tutorial introduction to the basic concepts in bifurcation theory and continuation methods.

  19. POSSIBILITIES OF USING THE FLUORESCENCE IN SITU HYBRIDIZATION TECHNIQUE IN THE DIAGNOSIS OF BLADDER CANCER AND ITS RECURRENCES

    Directory of Open Access Journals (Sweden)

    V. B. Matveev

    2014-07-01

    Full Text Available Fluorescence in situ hybridization is a current technique to detect chromosomal specific genetic disorders specific to urinary bladder cancer (UBC. This technique may be used to diagnose UBC, to follow up patients after surgical treatment, to evaluate the efficiency of adjuvant therapy in these patients, and to predict the development of disease recurrence.

  20. Diagnosis of In Situ Metabolic State and Rates of Microbial Metabolism During In Situ Uranium Bioremediation with Molecular Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lovley, Derek R. [University of Massachusetts, Amherst

    2012-11-28

    The goal of these projects was to develop molecule tools to tract the metabolic activity and physiological status of microorganisms during in situ uranium bioremediation. Such information is important in able to design improved bioremediation strategies. As summarized below, the research was highly successful with new strategies developed for estimating in situ rates of metabolism and diagnosing the physiological status of the predominant subsurface microorganisms. This is a first not only for groundwater bioremediation studies, but also for subsurface microbiology in general. The tools and approaches developed in these studies should be applicable to the study of microbial communities in a diversity of soils and sediments.

  1. Assessment of phytoremediation as an in-situ technique for cleaning oil-contaminated sites

    International Nuclear Information System (INIS)

    Literature on examples of phytoremediation techniques used in the in-situ remediation of soils contaminated by petroleum hydrocarbons is reviewed. The review includes discussion of the key mechanisms involved in each case, benefits, limitations and costs compared to alternative approaches, including natural attenuation, engineering and bioremediation. Review of the literature led to the conclusion that phytoremediation is an effective method for degrading and containing petroleum hydrocarbons in soil, and confirmed the ability of plants to transfer volatile petroleum hydrocarbons, such as napthalene, from the soil to the atmosphere via transpiration. The primary loss mechanism for the degradation of petroleum hydrocarbons appears to be microorganisms in the rhizosphere of plants. The available information also suggests that plants may degrade petroleum hydrocarbons directly, although the indirect role played by plants is far more common. These roles include supplying root exudates for microbial use, releasing root-associated enzymes that degrade contaminants in the soil, and altering soil to promote phytoremediation. BTEX compounds are most easily amenable to phytoremediation; large and lipophilic compounds such as four or five-ring polyaromatic hydrocarbons are more difficult to remediate. The limited information available suggests that phytoremediation is slightly less expensive than bioremediation, and several order of magnitude less than engineering techniques. Initude less than engineering techniques. In general, phytoremediation is faster than natural attenuation, but typically slower than engineering and bioremediation. On the other hand, it is less disruptive to the site than ex-situ engineering and bioremediation that involve excavation efforts. Phytoremediation is most effective with shallow contamination. Preliminary screenings indicate that there are several plant species, native and introduced, that may be used with some success for phytoremediation in the Prairie and Boreal Plains ecozones. The report includes a glossary and appendices listing types and behaviour of petroleum hydrocarbons, potential applications of phytoremediation in western Canada, and sources of information on phytoremediation on the Internet. 151 refs., tabs., figs

  2. In-situ health monitoring technique for composite structures utilizing embedded thermal fiber optic sensors

    Science.gov (United States)

    Stewart, Anna Kristina

    Health monitoring techniques are necessary for the safety, reliability and longevity of structural components. However, dependable, in-situ, and practical damage detection methods are difficult to develop and implement. In this dissertation, a novel health monitoring technique based on thermography that uses optical fiber thermal sensors to detect damage within a laminated graphite epoxy composite specimen is investigated. The concept follows: when an internal defect exists inside a composite panel and an external heat flux is applied, the defect can hinder the heat from propagating through the panel. Consequently, thermal sensors placed near the defect measure a temperature change when compared to a defect-free panel. Fiber optic sensors are permanently embedded within a structure to allow for direct temperature measurement and an in-situ health monitoring technique. Fiber optic sensors are advantageous primarily due to their multiplexing capabilities. Certain fiber optic technologies permit 1000 point sensors on a single fiber, which in turn reduces the cabling sizes by three orders of magnitude. A comprehensive proof-of-concept study involved five sets of composite samples and a numerical model. The first set validated the concept, the second tested two types of fiber optic sensors, the third provided a thorough study using the superior sensor technology, the fourth provided data to develop a numerical model, and the last set validated the model's findings. The numerical model provided a close approximation to the experimental data, and was used to determine proper sensor placement. The first three sets of specimens used a simulated impact system to induce damage of varying degrees into the samples. The last two sets used artificial damage in the form of Teflon inserts in an effort to quantify the size and location of damage. A flash lamp apparatus rapidly heated the samples while the fiber optic sensors and exterior thermocouples recorded temperature changes. Results confirm that the fiber optic thermal sensors can detect the presence and severity of damage.

  3. A Review of Voltage Stability Assessment Techniques with an Improved Voltage Stability Indicator

    Science.gov (United States)

    Danish, Mir Sayed Shah; Yona, Atsushi; Senjyu, Tomonobu

    2015-04-01

    A blackout can take place in entire power system or a part of the system due to extreme voltage instability (voltage collapse) that can appear abruptly. Instability prediction and continuous monitoring of the power system performance is, therefore, known exigent. This paper is conducted with a broad overview of the voltage stability indices, which are previously studied in the literature, and have the same foundation during their formulation. Afterward, an improved voltage stability indicator is introduced as a result of the multi-criteria integration and enhancement of the original indices by employing linear algebra methods. It is found that the proposed algorithm can overcome on the probable limitations from calculating point view. Then comparative analysis of the indices is presented in order to reach a unique consensus about the typical techniques of modal analysis (sensitivity, eigenvalue, right eigenvectors, and bus participation factor) as a precise algorithm. Finally, the IEEE 14-bus, and 30-bus test systems are selected to verify the algorithm, and compare the performance of the improved indicator approach with the existing indices.

  4. In situ monitoring technique for determining post remedial action concentrations of radium in soil

    International Nuclear Information System (INIS)

    There are several federal programs where action is being carried out to clean up or otherwise control residual radioactivity, at levels above current guidelines, which exists as a result of activities carried out during the early years of this nation's atomic energy program. At most of the sites which are candidates for clean up, the principal radionuclide of concern is Ra-226. Following excavation of open land areas, measuring the concentration of Ra-226 in soil samples from discrete locations or by indirect monitoring techniques. For application in remedial action programs, as in situ monitoring technique has been employed with favorable results. Instrumentation for this technique consists of a 2'' x 2'' NaI probe mounted on a wheeled dolly so that the detector is approximately 12'' above the ground. Radiation levels are read out using a portable digital ratemeter/scaler. Readings with this device are representative of photons which reach the detector from a ground area subtended by projection of the cone shield side wall. This system was calibrated using facilities at the Department of Energy Technical Measurements Center, Grand Junction, CO. A series of measurements at this facility revealed a conversion factor which relates the response for Ra-226 in dry soil: Ra-226 pCi/g = 1.06 x 10-3 (cpm) - 2.94. The correlation coefficient was 0.99. This technique has been used extensively to predict the Ra-226 soil concentration averaged over individual 100 m2 areas

  5. Sintering process optimization for multi-layer CGO membranes by in situ techniques

    DEFF Research Database (Denmark)

    Kaiser, Andreas; Prasad, A.S.

    2013-01-01

    The sintering of asymmetric CGO bi-layers (thin dense membrane on a porous support; Ce0.9Gd0.1O1.95-delta = CGO) with Co3O4 as sintering additive has been optimized by combination of two in situ techniques. Optical dilatometry revealed that bi-layer shape and microstructure are dramatically changing in a narrow temperature range of less than 100 degrees C. Below 1030 degrees C, a higher densification rate in the dense membrane layer than in the porous support leads to concave shape, whereas the densification rate of the support is dominant above 1030 degrees C, leading to convex shape. A fiat bi-layer could be prepared at 1030 degrees C, when shrinkage rates were similar. In situ van der Pauw measurements on tape cast layers during sintering allowed following the conductivity during sintering. A strong increase in conductivity and in activation energy E-a for conduction was observed between 900 and 1030 degrees C indicating an activation of the reactive sintering process and phase transformation of cobalt oxide. (C) 2012 Elsevier Ltd. All rights reserved.

  6. Comparative review of techniques used for in situ remediation of contaminated soils; Revision comparativa de tecnicas empleadas para la descontaminacion in situ de suelos contaminados

    Energy Technology Data Exchange (ETDEWEB)

    Escusol Tomey, M.; Rodriguez Abad, R.

    2014-07-01

    Soil pollution may influence the geotechnical parameters of the soil itself, properties such as solid particle density or water within its pores. It may also vary its friction angle, modify its structure and texture, or change the properties of its constitutive minerals due to the inclusion of polluting components. For these reasons, soil decontamination is an important factor to consider in geotechnics. This work focuses on those soil decontamination techniques carried out in situ, since they allow to eliminate soil pollutants in a less invasive way than confinement, containment or ex situ remediation techniques, causing a minor soil alteration and, therefore, affecting less to its mechanical properties. These factors should be taken into account when carrying out a geotechnical performance on a previously decontaminated soil. (Author)

  7. Application of voltammetric techniques at microelectrodes to the study of the chemical stability of highly reactive species.

    Science.gov (United States)

    Laborda, Eduardo; Olmos, José-Manuel; Torralba, Encarnación; Molina, Angela

    2015-02-01

    The application of voltammetric techniques to the study of chemical speciation and stability is addressed both theoretically and experimentally in this work. In such systems, electrode reactions are coupled to homogeneous chemical equilibria (complexations, protonations, ion associations, ...) that can be studied in a simple, economical, and accurate way by means of electrochemical methods. These are of particular interest when some of the participating species are unstable given that the generation and characterization of the species are performed in situ and on a short time scale. With the above aim, simple explicit solutions are presented in this article for quantitative characterization with any voltammetric technique and with the most common electrode geometries. From the theoretical results obtained, it is pointed out that the use of square-wave voltammetry in combination with microelectrodes is very suitable. Finally, the theory is applied to the investigation of the ion association between the anthraquinone radical monoanion and the tetrabutylammonium cation in acetonitrile medium. PMID:25551335

  8. Stabilized in situ rectangular MgB{sub 2} wires: the effect of B purity and sheath materials

    Energy Technology Data Exchange (ETDEWEB)

    Kovac, P; Birajdar, B; Husek, I; Holubek, T [Institute of Electrical Engineering, Centre of Excellence CENG, Slovak Academy of Sciences, Dubravska cesta 9, 841 04 Bratislava (Slovakia); Eibl, O [Institut fuer Angewandte Physik, Universitaet Tuebingen, Auf der Morgenstelle 10, D-72076 Tuebingen (Germany)

    2008-04-01

    Stabilized four-filament SiC-added in situ MgB{sub 2} wires were prepared by the rectangular wire-in-tube (RWIT) technique, using boron powders of different purity (90% and 99%), SiC powders of different agglomerate size and sheaths of different metals. The critical current density at 11 T and 4.2 K improved by 5-10 times by using boron powder of higher purity, SiC powder of small agglomerate size, a chemically inert Ti barrier and mechanical support provided by a Monel sheath. The decrease in critical temperature (T{sub c}) and increase in critical current density (J{sub c}) of wires could be explained in terms of carbon doping. Formation of Mg{sub 2}Si and B-rich secondary phases, and carbon substitution was studied using EDX chemical mapping in a scanning electron microscope (SEM). The addition of SiC results in the formation of B-rich secondary phases. Our results support the mechanism of carbon doping through the reaction of SiC with Mg to form Mg{sub 2}Si and release free carbon. However, the extent of effective carbon doping depends on the size of the precursor SiC agglomerates, as large SiC agglomerates are unable to react with Mg. B precursor powder of lower purity and Mg{sub 2}Si secondary phase formation led to incomplete phase formation of MgB{sub 2} and consequently to lowered J{sub c}.

  9. In situ growth of high temperature superconductor thin films with evaporation techniques using an ozone jet

    International Nuclear Information System (INIS)

    This paper reports on high quality YBa2Cu3O7 thin films grown in situ on various substrates (SrTiO3, Al2O3, Si) using MBE techniques and an ozone jet. The yttrium and copper are evaporated from electron gun sources and the barium is evaporated from a Knudsen cell. All sources are controlled by a single mass spectrometer feedback system to obtain the correct fluxes at high partial ozone pressures. During deposition the partial ozone pressure at the substrate position is estimated to be 10-3-10-2 mbar. The substrate holder temperature is 700 degrees C. The real substrate temperature is estimated to be lower than 650 degrees C. The films are analyzed with R(T), X-ray diffraction and RBS measurements. SEM photographs are taken of the surface

  10. Towards a more realistic picture of in situ biocide actions: Combining physiological and microscopy techniques

    International Nuclear Information System (INIS)

    In this study, we combined chlorophyll a fluorescence (ChlaF) measurements, using pulse-amplitude-modulate (PAM) equipment, with scanning electron microscopy in backscattered electron mode (SEM-BSE) and transmission electron microscopy (TEM) images to evaluate the actions of Koretrel at lower concentrations on Verrucaria nigrescens colonising a dolostone. ChlaF measurements are good indicators of the damaging effects of biocides. However, these indicators only provide an incomplete view of the mechanism of biocides used to control biodeterioration agents. The death of the V. nigrescens photobiont at two biocide concentrations was revealed by PAM, SEM-BSE and TEM. Once Koretrel was applied, the Fv/Fm ratios markedly fell in the first few hours after the 1.5% treatment, and ratios for the 3% dilution remained close to zero throughout the study. The algal zone shows the plasmolysed appearance of the photobiont cells, and important aspects related to the action of the biocide on free and lichenised fungi were also detected using SEM-BSE. Many of the mycobiont cells had only their cell walls preserved; although, some fungal hyphae in lichen thalli and some microorganisms in endolithic clusters maintained lipid storage in their cytoplasm. These results indicated that the combination of physiological and microscopy techniques improves the assessment of biocide action in situ and this will help to optimize protocols in order to reduce the emission of these compounds to the environment. -- Highlights: ? We combined ChlaF measurements with EM images to analyses the biocides action on stone biodeterioration agents. ? At lower biocide concentrations damage to photobiont and mycobiont cells integrity, ultrastructure and vitality were observed. ? The limited action of biocides on fungi and algae were detected using SEM-BSE. ? The combination of physiological and microscopy techniques improves the assessment of biocide action in situ. ? This new approach will help to optimize protocols of biocide application on stone.

  11. Direct push driven in situ color logging tool (CLT): technique, analysis routines, and application

    Science.gov (United States)

    Werban, U.; Hausmann, J.; Dietrich, P.; Vienken, T.

    2014-12-01

    Direct push technologies have recently seen a broad development providing several tools for in situ parameterization of unconsolidated sediments. One of these techniques is the measurement of soil colors - a proxy information that reveals to soil/sediment properties. We introduce the direct push driven color logging tool (CLT) for real-time and depth-resolved investigation of soil colors within the visible spectrum. Until now, no routines exist on how to handle high-resolved (mm-scale) soil color data. To develop such a routine, we transform raw data (CIEXYZ) into soil color surrogates of selected color spaces (CIExyY, CIEL*a*b*, CIEL*c*h*, sRGB) and denoise small-scale natural variability by Haar and Daublet4 wavelet transformation, gathering interpretable color logs over depth. However, interpreting color log data as a single application remains challenging. Additional information, such as site-specific knowledge of the geological setting, is required to correlate soil color data to specific layers properties. Hence, we exemplary provide results from a joint interpretation of in situ-obtained soil color data and 'state-of-the-art' direct push based profiling tool data and discuss the benefit of additional data. The developed routine is capable of transferring the provided information obtained as colorimetric data into interpretable color surrogates. Soil color data proved to correlate with small-scale lithological/chemical changes (e.g., grain size, oxidative and reductive conditions), especially when combined with additional direct push vertical high resolution data (e.g., cone penetration testing and soil sampling). Thus, the technique allows enhanced profiling by means of providing another reproducible high-resolution parameter for analysis subsurface conditions. This opens potential new areas of application and new outputs for such data in site investigation. It is our intention to improve color measurements by means method of application and data interpretation, useful to characterize vadose layer/soil/sediment characteristics.

  12. A double labeling technique for performing immunocytochemistry and in situ hybridization in virus infected cell cultures and tissues

    International Nuclear Information System (INIS)

    This report describes a combined immunocytochemical and in situ hybridization procedure which allows visualization of cellular or viral antigens and viral RNA in the same cell. Cultures infected with visna or measles virus were fixed in periodate-lysine-paraformaldehyde-glutaraldehyde, stained by the avidin-biotin-peroxidase technique using antibodies to viral or cellular proteins and then incubated with radiolabeled specific DNA probes (in situ hybridization). This technique provides a new approach to the study of viral pathogenesis by: (1) identifying the types of cells which are infected in the host and (2) identifying points of blockade in the virus life cycle during persistent infections. (Auth.)

  13. In situ preparation of fluorescent CdTe quantum dots with small thiols and hyperbranched polymers as co-stabilizers

    Science.gov (United States)

    Shi, Yunfeng; Ma, Zhimin; Cui, Ningning; Liu, Yanli; Hou, Xiaoyu; Du, Weimin; Liu, Lin; Gangsheng, Tong

    2014-03-01

    A new strategy for in situ preparation of highly fluorescent CdTe quantum dots (QDs) with 3-mercaptopropionic acid (MPA) and hyperbranched poly(amidoamine)s (HPAMAM) as co-stabilizers was proposed in this paper. MPA and HPAMAM were added in turn to coordinate Cd2+. After adding NaHTe and further microwave irradiation, fluorescent CdTe QDs stabilized by MPA and HPAMAM were obtained. Such a strategy avoids the aftertreatment of thiol-stabilized QDs in their bioapplication and provides an opportunity for direct biomedical use of QDs due to the existence of biocompatible HPAMAM. The resulting CdTe QDs combine the mechanical, biocompatibility properties of HPAMAM and the optical, electrical properties of CdTe QDs together.

  14. Review of in situ tokamak detritiation techniques: current status and remaining open issues before ITER implementation

    International Nuclear Information System (INIS)

    The in vessel tritium inventory control is one of the most ITER challenging issues which has to be performed to fulfil safety requirements. This is due mainly to the presence of Carbon as a constituent of Plasma Facing Material (PFM) which leads to a high fuel permanent retention. For several years now, physics studies and technological developments have been undertaken worldwide in order to develop reliable techniques which could be used in ITER severe environment (Magnetic field, vacuum, high temperature) for in situ tritium recovery. The scope of this presentation is to review the present status of these achievements and define the remaining work to be done in order to propose a dedicated work program. A brief description of the major results observed in tokamak concerning erosion, particle transport et redeposition of wall constituents will be first presented. We will also focus on fuel trapping in the PFM and co deposited layer with a special insight of results obtained during tokamak long pulse operation. A particular attention will be devoted to the observed properties of mixed material as beryllium Carbide and on the expected consequences on material treatment. From these results, an extrapolation to the ITER operation constraints will be crudely established. The different treatment techniques currently used in fusion devices will be then reviewed from usual conditioning procedures as Glow discharge to radio frequency or tokamak plasma assisted techniques. In the frame of ITER, they will be compared in term of fuel removal efficiency. The capability of treating complex surfaces as voids or castellated structure as well as remote area will be also addressed. The necessity to use additional in situ surface treatments in order to maintain tritium inventory under safety limits will be addressed. These treatments mainly based on photo-cleaning (flash lamp or laser) or oxidation will be reviewed in term of possible consequences on plasma operation and of expected technological problem. Ad last, a work program which has to be undertaken in term of fusion technology developments in order to fulfil ITER requirements on PFC treatments will be presented. (author)

  15. Robust design of decentralized power system stabilizers using meta-heuristic optimization techniques for multimachine systems

    Directory of Open Access Journals (Sweden)

    Jeevanandham Arumugam

    2009-01-01

    Full Text Available In this paper a classical lead-lag power system stabilizer is used for demonstration. The stabilizer parameters are selected in such a manner to damp the rotor oscillations. The problem of selecting the stabilizer parameters is converted to a simple optimization problem with an eigen value based objective function and it is proposed to employ simulated annealing and particle swarm optimization for solving the optimization problem. The objective function allows the selection of the stabilizer parameters to optimally place the closed-loop eigen values in the left hand side of the complex s-plane. The single machine connected to infinite bus system and 10-machine 39-bus system are considered for this study. The effectiveness of the stabilizer tuned using the best technique, in enhancing the stability of power system. Stability is confirmed through eigen value analysis and simulation results and suitable heuristic technique will be selected for the best performance of the system.

  16. Testing the Chemical/Structural Stability of Proton Conducting Perovskite Ceramic Membranes by in Situ/ex Situ Autoclave Raman Microscopy

    Science.gov (United States)

    Slodczyk, Aneta; Zaafrani, Oumaya; Sharp, Matthew D.; Kilner, John A.; Dabrowski, Bogdan; Lacroix, Olivier; Colomban, Philippe

    2013-01-01

    Ceramics, which exhibit high proton conductivity at moderate temperatures, are studied as electrolyte membranes or electrode components of fuel cells, electrolysers or CO2 converters. In severe operating conditions (high gas pressure/high temperature), the chemical activity towards potentially reactive atmospheres (water, CO2, etc.) is enhanced. This can lead to mechanical, chemical, and structural instability of the membranes and premature efficiency loss. Since the lifetime duration of a device determines its economical interest, stability/aging tests are essential. Consequently, we have developed autoclaves equipped with a sapphire window, allowing in situ Raman study in the 25–620 °C temperature region under 1–50 bar of water vapor/gas pressure, both with and without the application of an electric field. Taking examples of four widely investigated perovskites (BaZr0.9Yb0.1O3??, SrZr0.9Yb0.1O3??, BaZr0.25In0.75O3??, BaCe0.5Zr0.3Y0.16Zn0.04O3??), we demonstrate the high potential of our unique set-up to discriminate between good/stable and instable electrolytes as well as the ability to detect and monitor in situ: (i) the sample surface reaction with surrounding atmospheres and the formation of crystalline or amorphous secondary phases (carbonates, hydroxides, hydrates, etc.); and (ii) the structural modifications as a function of operating conditions. The results of these studies allow us to compare quantitatively the chemical stability versus water (corrosion rate from ~150 µm/day to less than 0.25 µm/day under 200–500 °C/15–80 bar PH2O) and to go further in comprehension of the aging mechanism of the membrane. PMID:24957060

  17. Conceptual design for the demonstration and evaluation of stabilization and closure techniques of a low-level radioactive waste disposal site

    International Nuclear Information System (INIS)

    Long term stabilization and closure of radioactive or hazardous waste disposal sites is a critical element in waste management which is presently undemonstrated. This report represents an integration of stabilization and closure methodology researched at ORNL and other locations into a design, and ultimately a demonstration of long term passive stabilization and closure techniques. The chosen demonstration site is a 19 trench low level waste disposal site within Solid Waste Storage Area (SWSA) No. 6 at ORNL. Design criteria included prevention of biological intrusion (animals and plant roots), waste stabilization, hydrological isolation, failure detection, run-off and infiltration monitoring, and passive performance evaluation capability. These criteria are satisfied through incorporation of these basic components: dynamic compaction; in situ chemical grouting; high density polyethylene (HDPE); high swelling bentonite; rock/gravel animal and root barrier; native soil cap; and under-cap and surface drainage

  18. Measurement of in-situ stress in salt and rock using NQR techniques

    International Nuclear Information System (INIS)

    A discussion of how stress and strain affect the quantities which can be measured in an NQR experiment shows that, for stresses of the magnitude to be expected at depths up to about 10,000 feet, quadrupole coupling constants will fall in the range of 1 to 10 kHz for both the sodium and chloride ions in NaCl. The most promising system involves pulsed nuclear double resonance detection; and alterative is to observe the quadrupolar splitting of the NMR signal. Choices to be made in the measurement and mapping techniques are discussed. The well-known perturbation of the homogenous stress field in the neighborhood of a borehole is shown to be advantageous from the point of view of obtaining directional information on the stress. Construction and operation of a borehole stress sensor are considered. The NQR technique seems feasible for measuring the magnitude and direction of underground stress with a resolution of about 25 psi, or 2.5% at 1000 psi. Downhole instrumentation suitable for in-situ determinations of stress appears within the state of the art. Additional tasks required on the project are identified

  19. Establishment of the genomic in situ hybridization (GISH) technique for analysis in interspecific hybrids of Passiflora.

    Science.gov (United States)

    Melo, C A F; Silva, G S; Souza, M M

    2015-01-01

    The genomic in situ hybridization (GISH) technique was applied to Passiflora interspecific F1 HD13-133 hybrids (Passiflora sublanceolata x Passiflora foetida) and HD15-101 (Passiflora gardineri x Passiflora gibertii), and the backcrossed hybrids (BC1) HD18-106 and HD18-113 (Passiflora sublanceolata x HD13-133). GISH was performed using genomic probes prepared with the DNA from the paternal genitor, whereas the maternal DNA was used as blocking DNA and employed at various concentrations (20X, 40X, 60X, and 100X) in relation to the probe concentration. At the same time, GISH was applied with the use of simultaneous probes from both genomes, paternal and maternal, that were detected with avidin-FITC and anti-digoxigenin-rhodamine, respectively. Both methodologies allowed the distinguishing of the maternal and paternal genomes, thus confirming the hybrid nature of all the analyzed genotypes. Furthermore, the presence of recombinant chromosomes in BC1 hybrids revealed the occurrence of meiotic recombination in HD13 hybrids. This application of the GISH technique is an important step towards genomic analyses of Passiflora hybrids: it can broaden the phylogenetic and evolutionary studies of the genus and, at the same time, contribute to breeding programs. PMID:25867365

  20. Measurement of in-situ stress in salt and rock using NQR techniques

    Energy Technology Data Exchange (ETDEWEB)

    Schempp, E.; Hirschfeld, T.; Klainer, S.

    1980-12-01

    A discussion of how stress and strain affect the quantities which can be measured in an NQR experiment shows that, for stresses of the magnitude to be expected at depths up to about 10,000 feet, quadrupole coupling constants will fall in the range of 1 to 10 kHz for both the sodium and chloride ions in NaCl. The most promising system involves pulsed nuclear double resonance detection; and alterative is to observe the quadrupolar splitting of the NMR signal. Choices to be made in the measurement and mapping techniques are discussed. The well-known perturbation of the homogenous stress field in the neighborhood of a borehole is shown to be advantageous from the point of view of obtaining directional information on the stress. Construction and operation of a borehole stress sensor are considered. The NQR technique seems feasible for measuring the magnitude and direction of underground stress with a resolution of about 25 psi, or 2.5% at 1000 psi. Downhole instrumentation suitable for in-situ determinations of stress appears within the state of the art. Additional tasks required on the project are identified.

  1. In Situ Determination of Sulfate Reduction in Peatlands - A Downscaled Push-Pull Tracer Technique

    Science.gov (United States)

    Goldhammer, T.; Blodau, C.

    2005-12-01

    Microbial dissimilatory sulfate reduction is a key process for carbon cycling in nutrient-poor peatlands. For an estimation of a future behaviour of these carbon-rich ecosystems under altered environmental conditions, reliable methods for a quantification of biogeochemical processes still have to be developed. In general, sulfate reduction is being quantified via laboratory-scale incubation experiments with field samples. A main disadvantage and source of uncertainty of this approach is the use of disturbed samples and the determination of not actual but potential turnover rates, which can not easily be extrapolated to the field scale. In order to find an alternative for measuring sulfate reduction in peat soils we developed an experimental design derived from hydrogeological practice, where single-well push-pull tracer tests are widely used for in situ determination of microbial activities in aquifers. A mixture of a conservative tracer and a reactant is injected into a well and regained after a certain time of in situ incubation. Assuming that sulfate reduction follows mainly first-order reaction kinetics, the analysis of the obtained breakthrough curve data is simple. The slope of a log-linear regression of the ratio of relative reactant vs. tracer concentrations plotted against time since injection delivers the reaction rate coefficient k. Nine piezometers installed at three depth levels (20-30, 30-40 and 50-60cm below ground surface) in Mer Bleue Bog, Ontario, Canada were used to conduct three series of push-pull tracer tests. In both uppermost depth-levels, increased hydraulic conductivity causes a dominance of lateral flow and leads to lower recovery rates. Nevertheless, with restrictions due to a higher sensitivity to operational errors, data from these replicates could be used for method evaluation. Mean k values ranged from -7.2*10-3 to -11.7*10-3 h-1. Positive k values representing increasing sulfate concentrations were determined in several series of the upper levels. We concluded that sulfate was not net consumed in the shallow peat. These first results indicate that small scale push-pull tests are a suitable technique for the determination of biogeochemical in situ reaction rates.

  2. Pilot demonstration for containment using in situ soil mixing techniques at a chemical disposal superfund site

    International Nuclear Information System (INIS)

    Kiber Environmental Services, Inc. (Kiber), under contract to McLaren-Hart Corporation and the site PRP group, performed technical oversight and on-site sampling and analyses at the confidential site located in Texas. The site consists of 15,000 cubic meters (20,000 cubic yards) of contaminated materials that were to be solidified on-site. The contaminants included heavy metals, PAHs, oil and grease, and volatile organics. Groundwater is less than 1 meter from the surface. Kiber was retained after several unsuccessful efforts to find on-site containment methods that effectively solidified the waste pits while achieving the performance goals. The PRP group then contracted with Kiber to perform the treatability and pilot oversight studies. The full-scale pilot demonstration was performed by Geo-Con. Pilot-scale treatment was performed to evaluate the effectiveness of in situ solidification treatment at achieving the site specific performance criteria, including an unconfined compressive strength of greater than 170 kPa (25 psi) and a permeability of less than 1x10-6 cm/sec. Technical oversight and on-site sampling and analysis were provided to evaluate pilot-scale application of the selected technology and verify treatment effectiveness. The project was divided into several subtasks. First, laboratory treatability testing was conducted to verify that performance specifications were achievable using the proposed reagent formulations. Next, a pilot demonstration was performed by Geo-Con using a Manotowoc 4000 crane equipped with a 1.5-meter diameter auger to evaluate shallow soil mixing. The final task included a comparative study between the performance of test specimens collected using wet sampling techniques versus in situ post-treatment coring

  3. Pilot demonstration for containment using in situ soil mixing techniques at a chemical disposal superfund site

    Energy Technology Data Exchange (ETDEWEB)

    Zarlinski, S.J.; Kingham, N.W.; Semenak, R. [Kiber Environmental Services, Inc., Atlanta, GA (United States)

    1997-12-31

    Kiber Environmental Services, Inc. (Kiber), under contract to McLaren-Hart Corporation and the site PRP group, performed technical oversight and on-site sampling and analyses at the confidential site located in Texas. The site consists of 15,000 cubic meters (20,000 cubic yards) of contaminated materials that were to be solidified on-site. The contaminants included heavy metals, PAHs, oil and grease, and volatile organics. Groundwater is less than 1 meter from the surface. Kiber was retained after several unsuccessful efforts to find on-site containment methods that effectively solidified the waste pits while achieving the performance goals. The PRP group then contracted with Kiber to perform the treatability and pilot oversight studies. The full-scale pilot demonstration was performed by Geo-Con. Pilot-scale treatment was performed to evaluate the effectiveness of in situ solidification treatment at achieving the site specific performance criteria, including an unconfined compressive strength of greater than 170 kPa (25 psi) and a permeability of less than 1x10{sup -6} cm/sec. Technical oversight and on-site sampling and analysis were provided to evaluate pilot-scale application of the selected technology and verify treatment effectiveness. The project was divided into several subtasks. First, laboratory treatability testing was conducted to verify that performance specifications were achievable using the proposed reagent formulations. Next, a pilot demonstration was performed by Geo-Con using a Manotowoc 4000 crane equipped with a 1.5-meter diameter auger to evaluate shallow soil mixing. The final task included a comparative study between the performance of test specimens collected using wet sampling techniques versus in situ post-treatment coring.

  4. Following the Transient Reactions in Lithium-Sulfur Batteries Using In an In Situ Nuclear Magnetic Resonance Technique

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Jie; Hu, Jian Z.; Chen, Honghao; Vijayakumar, M.; Zheng, Jianming; Pan, Huilin; Walter, Eric D.; Hu, Mary Y.; Deng, Xuchu; Feng, Ju; Liaw, Bor Yann; Gu, Meng; Deng, Zhiqun; Lu, Dongping; Xu, Suochang; Wang, Chong M.; Liu, Jun

    2015-05-13

    Li-S batteries hold great potential for next-generation, large-format power source applications; yet, the fundamental understanding of the electrochemical reaction pathways remains lacking to enable their functionality as promised. Here, in situ NMR technique employing a specially designed cylindrical micro battery was used to monitor the chemical environments around Li+ ions during repetitive charge-discharge process and track the transient electrochemical and chemical reactions occurring in the whole Li-S system. The in situ NMR provides real time, quantitative information related to the temporal concentration variations of the polysulfides with various chain lengths, providing important clues for the reaction pathways during both discharge and charge processes. The in-situ technique also reveals that redox reactions may involve transient species that are difficult to detect in ex-situ NMR study. Intermediate species such as charged free radicals may play an important role in the formation of the polysulfide products. Additionally, in situ NMR measurement simultaneously reveals vital information on the 7Li chemical environments in the electrochemical and parasitic reactions on the lithium anode that promotes the understanding of the failure mechanism in the Li-S system. These new insights could help design effective strategies to accelerate the development of Li-S battery technology.

  5. Development and clinical application of an innovative fluorescence in situ hybridization technique which detects submicroscopic rearrangements involving telomeres.

    OpenAIRE

    Knight, Sj; Horsley, Sw; Regan, R.; Lawrie, Nm; Maher, Ej; Cardy, Dl; Flint, J.; Kearney, L.

    1997-01-01

    We report an innovative fluorescence in situ hybridization technique which exploits a unique resource of 41 telomere-specific probes and allows the simultaneous analysis of the subtelomeric region of every chromosome for deletion, triplication and balanced translocation events. This technique requires only a single microscope slide per patient and is expected to be a useful diagnostic tool with applications in the fields of idiopathic mental retardation, the detection of congenital abnormalit...

  6. Towards a more realistic picture of in situ biocide actions: Combining physiological and microscopy techniques

    Energy Technology Data Exchange (ETDEWEB)

    Speranza, M., E-mail: speranzamariela@gmail.com [Museo Nacional de Ciencias Naturales, MNCN-CSIC, Serrano 115 bis, 28006 Madrid (Spain); Wierzchos, J.; De Los Rios, A.; Perez-Ortega, S. [Museo Nacional de Ciencias Naturales, MNCN-CSIC, Serrano 115 bis, 28006 Madrid (Spain); Souza-Egipsy, V. [Instituto de Ciencias Agrarias, ICA-CSIC, Serrano 115 bis, 28006 Madrid (Spain); Ascaso, C., E-mail: ascaso@mncn.csic.es [Museo Nacional de Ciencias Naturales, MNCN-CSIC, Serrano 115 bis, 28006 Madrid (Spain)

    2012-11-15

    In this study, we combined chlorophyll a fluorescence (ChlaF) measurements, using pulse-amplitude-modulate (PAM) equipment, with scanning electron microscopy in backscattered electron mode (SEM-BSE) and transmission electron microscopy (TEM) images to evaluate the actions of Koretrel at lower concentrations on Verrucaria nigrescens colonising a dolostone. ChlaF measurements are good indicators of the damaging effects of biocides. However, these indicators only provide an incomplete view of the mechanism of biocides used to control biodeterioration agents. The death of the V. nigrescens photobiont at two biocide concentrations was revealed by PAM, SEM-BSE and TEM. Once Koretrel was applied, the Fv/Fm ratios markedly fell in the first few hours after the 1.5% treatment, and ratios for the 3% dilution remained close to zero throughout the study. The algal zone shows the plasmolysed appearance of the photobiont cells, and important aspects related to the action of the biocide on free and lichenised fungi were also detected using SEM-BSE. Many of the mycobiont cells had only their cell walls preserved; although, some fungal hyphae in lichen thalli and some microorganisms in endolithic clusters maintained lipid storage in their cytoplasm. These results indicated that the combination of physiological and microscopy techniques improves the assessment of biocide action in situ and this will help to optimize protocols in order to reduce the emission of these compounds to the environment. -- Highlights: Black-Right-Pointing-Pointer We combined ChlaF measurements with EM images to analyses the biocides action on stone biodeterioration agents. Black-Right-Pointing-Pointer At lower biocide concentrations damage to photobiont and mycobiont cells integrity, ultrastructure and vitality were observed. Black-Right-Pointing-Pointer The limited action of biocides on fungi and algae were detected using SEM-BSE. Black-Right-Pointing-Pointer The combination of physiological and microscopy techniques improves the assessment of biocide action in situ. Black-Right-Pointing-Pointer This new approach will help to optimize protocols of biocide application on stone.

  7. In Situ Stabilization of Trace Metals in a Copper-Contaminated Soil using P-Spiked Linz-Donawitz Slag

    OpenAIRE

    Negim, O.; Mench, Michel; Bes, Cle?mence; Motelica-heino, Mikael; Amin, Fouad; Le Coustumer, Philippe

    2012-01-01

    P-spiked Linz-Donawitz (LD) slag was used as a soil additive to improve physico-chemical soil properties and in situ stabilize Cu and other trace metals in a sandy Cu-contaminated soil (630 mg kg-1 soil) from a former wood preservation site. The LD slag was incorporated into the contaminated soil to consist four treatments: 0 % (T1), 1 % (T2), 2 % (T3), and 4 % (T4) per air-dried soil weight. A similar uncontaminated soil was used as a control (CTRL). After a one-month reaction period, potted...

  8. In situ characterization of catalytic activity of graphene stabilized small-sized Pd nanoparticles for CO oxidation

    International Nuclear Information System (INIS)

    The room-temperature ionic liquid assisted sputtering method is utilized to achieve the Pd-nanoparticle (NP)–graphene hybrid. The supported Pd NPs possess uniformly small sizes of 1–2 nm, which create huge surface area with ultralow Pd consumption and high NP stability. The Pd-NP–graphene hybrid is in situ characterized by the ambient pressure X-ray photoelectron spectroscopy using synchrotron radiation, and the results demonstrate high catalytic activity of the hybrid for CO oxidation. The catalytic behavior is reproducible for several catalytic cycles. The present simple and clean approach is promising to produce metal-NP-based high-efficiency catalysts for CO oxidation

  9. Transmission Electron Microscope In Situ Straining Technique to Directly Observe Defects and Interfaces During Deformation in Magnesium

    Science.gov (United States)

    Morrow, B. M.; Cerreta, E. K.; McCabe, R. J.; Tomé, C. N.

    2015-05-01

    In situ straining was used to study deformation behavior of hexagonal close-packed (hcp) metals. Twinning and dislocation motion, both essential to plasticity in hcp materials, were observed. Typically, these processes are characterized postmortem by examining remnant microstructural features after straining has occurred. By imposing deformation during imaging, direct observation of active deformation mechanisms is possible. This work focuses on straining of structural metals in a transmission electron microscope (TEM), and a recently developed technique that utilizes familiar procedures and equipment to increase ease of experiments. In situ straining in a TEM presents several advantages over conventional postmortem characterization, most notably time resolution of deformation and streamlined identification of active deformation mechanisms. Drawbacks to the technique and applicability to other studies are also addressed. In situ straining is used to study twin boundary motion in hcp magnesium. A {10bar{1}2} } twin was observed during tensile and compressive loading. Twin-dislocation interactions are directly observed. Notably, dislocations are observed to remain mobile, even after multiple interactions with twin boundaries; this result suggests that Basinki's dislocation transformation mechanism by twinning is not present in hcp metals. The coupling of in situ straining with traditional postmortem characterization yields more detailed information about material behavior during deformation than either technique alone.

  10. Fabrication of Cu-sheathed MgB2 wire with high Jc-B performance using a mixture of in situ and ex situ PIT techniques

    International Nuclear Information System (INIS)

    This work investigated methods of fabricating Cu-sheathed MgB2 wire, and succeeded in producing samples with enhanced Jc-B performance. Initially, MgB2/Cu wires were fabricated using either insitu or ex situ routes of the powder in tube (PIT) technique. The Jc-B performance of insitu MgB2/Cu wire is better (especially at lower magnetic fields) than that of the ex situ MgB2/Cu wire. However, the absolute Jc value was not particularly high (Jc at 6 T ? 3.4 x 102 A/cm2-4.2 K). As the next step, we tried to fabricate MgB2/Cu wire by the double core method, which enabled us to obtain wire in which the outer and inner cores correspond to ex situ and insitu wires, respectively. In this case, the Jc-B performance is drastically enhanced and the Jc at 6 T was 3.5 times higher (?1.2 x 103 A/cm2) than that of simple insitu MgB2/Cu wire. The double core method does not require special expensive tools, and there are many possibilities for future improvements in the wire. Therefore, we believe that this double core MgB2/Cu wire has a strong potential for the industrial fabrication of MgB2 wire with in-demand sheath materials such as Cu or Al.

  11. Thermal stability and in situ SiN passivation of InAlN/GaN high electron mobility heterostructures

    International Nuclear Information System (INIS)

    We investigate the thermal stability of nearly lattice-matched InAlN layers under metal organic vapor phase epitaxy conditions for temperatures >800?°C and show that they are not fully stable. In particular, InAlN top layers undergo degradation during high temperature annealing due to a surface related process, which causes the loss of crystal quality. This strongly impacts the transport properties of InAlN/GaN HEMT heterostructures; in particular, the mobility is significantly reduced. However, we demonstrate that high thermal stability can be achieved by capping with a GaN layer as thin as 0.5?nm. Those findings enabled us to realize in situ passivated HEMT heterostructures with state of the art transport properties.

  12. Thermal stability and in situ SiN passivation of InAlN/GaN high electron mobility heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Lugani, L.; Carlin, J.-F.; Py, M. A.; Grandjean, N. [ICMP, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland)

    2014-09-15

    We investigate the thermal stability of nearly lattice-matched InAlN layers under metal organic vapor phase epitaxy conditions for temperatures >800?°C and show that they are not fully stable. In particular, InAlN top layers undergo degradation during high temperature annealing due to a surface related process, which causes the loss of crystal quality. This strongly impacts the transport properties of InAlN/GaN HEMT heterostructures; in particular, the mobility is significantly reduced. However, we demonstrate that high thermal stability can be achieved by capping with a GaN layer as thin as 0.5?nm. Those findings enabled us to realize in situ passivated HEMT heterostructures with state of the art transport properties.

  13. Thermal stability and in situ SiN passivation of InAlN/GaN high electron mobility heterostructures

    Science.gov (United States)

    Lugani, L.; Carlin, J.-F.; Py, M. A.; Grandjean, N.

    2014-09-01

    We investigate the thermal stability of nearly lattice-matched InAlN layers under metal organic vapor phase epitaxy conditions for temperatures >800 °C and show that they are not fully stable. In particular, InAlN top layers undergo degradation during high temperature annealing due to a surface related process, which causes the loss of crystal quality. This strongly impacts the transport properties of InAlN/GaN HEMT heterostructures; in particular, the mobility is significantly reduced. However, we demonstrate that high thermal stability can be achieved by capping with a GaN layer as thin as 0.5 nm. Those findings enabled us to realize in situ passivated HEMT heterostructures with state of the art transport properties.

  14. Assessment of phytoremediation as an in-situ technique for cleaning oil-contaminated sites

    International Nuclear Information System (INIS)

    The effectiveness of phytoremediation as a tool for cleaning up hydrocarbon contaminated soil and groundwater was evaluated by reviewing relative literature. Phytoremediation is an emerging technology which consists of the use of plants for in situ treatment of contaminated soils. Grasses, herbs, shrubs and deciduous trees were the main types of plants considered in this study. A database is presently under construction to act as an inventory of plant species that tolerate or phytoremediate petroleum hydrocarbons. This paper focused on the main mechanisms and special considerations involved in the phytoremediation alkanes, aromatics, polycyclic aromatic hydrocarbons, and creosote. While phytoremediation does not require intensive engineering techniques, it does involve human intervention to establish appropriate plants and microorganisms to enhance natural degradation processes. Plants such as canola, oats barley have been shown to tolerate and accumulate metals such as selenium, copper, cadmium and zinc. Hybrid poplar trees reduce the concentration of nitrate in surficial groundwater and degrade the herbicide atrazine. Forage grasses inoculated with bacteria can degrade chlorinated benzoic acids. Various grasses and leguminous plants can increase the removal of petroleum hydrocarbons from contaminated soils. 66 refs., 3 tabs., 2 figs

  15. New techniques required to understand the by-stander effect in situ.

    Science.gov (United States)

    Britten, Richard

    2008-03-01

    The by-stander effect has been known for nearly a century under various names, of which the abscopal effect is probably the most well known. More recently the by-stander effect has received a lot of attention, and various models have been developed to assess the relative importance of the bystander effect in radiation treatment. It is clear that irradiated cells release factors that lead to alterations in the physiology of adjacent irradiated cells, both via inter-cellular junctions and through systemic factors. Most studies that have sought to identify the systemic factors and the cellular mechanisms that are responsible for the bystander effect have by necessity used in vitro systems. The purpose of this presentation is to alert the audience to the various techniques that are available to study the proteomic changes related to the bystander effect in situ. We shall pay attention to the use of MALDI-imaging to track spatial proteomic changes in tissue that have been exposed to microbeams.

  16. Valve disruption for in situ vein bypass: use of a new technique.

    Science.gov (United States)

    Enzler, M A; Smith, L L

    1991-11-01

    Following its introduction in 1960, the in situ bypass technique has gradually gained acceptance among vascular surgeons. This can be explained, in part, by the lack of a reliable method for rendering vein valves incompetent. Several instruments developed by Skagseth and Hall, Leather and Karmody, and others have been used. Although most are relatively easy to use, one common drawback is the difficulty in controlling rotation of the cutting blade. This is due to insufficient torsional rigidity of the shaft and the lack of a blade plane indicator. Edwards, in 1936, described the consistent orientation of vein valves, whose margins are always parallel to the overlying skin surface. This knowledge facilitates complete midline incision of the valve cusps, provided that the surgeon is able to control the cutting blade. With this fact in mind, we have developed a new set of instruments. They feature satisfactory torsional rigidity, as well as blade plane indicators at the handle. For the endoscopist, the blade plane is made visible by a mark at the tip of each instrument. Precision-manufactured of stainless steel and welded with laser technology, the instruments are suitable for multiple use, which we consider an advantage from an economic, as well as an ecological viewpoint. PMID:1772767

  17. In situ assessment of the saliva effect on enamel morphology after microabrasion technique

    Scientific Electronic Library Online (English)

    Núbia Inocencya Pavesi, Pini; Débora Alves Nunes Leite, Lima; Renato Herman, Sundfeld; Gláucia Maria Bovi, Ambrosano; Flávio Henrique Baggio, Aguiar; José Roberto, Lovadino.

    2014-09-01

    Full Text Available AIM: This study evaluated saliva effects on enamel morphology surface after microabrasion technique. METHODS: Enamel blocks (16 mm2) obtained from bovine incisors were divided into 9 groups as follows: one control group (no treatment), four groups with microabrasion treatment using 35% phospho [...] ric acid and pumice (H3PO4+Pum) and other four groups treated with 6.6% hydrochloric acid and silica (HCl+Sil). One group of each treatment was submitted to 4 frames of saliva exposure: without exposure, 1-h exposure, 24-h exposure, and 7-days exposure on in situ regimen. Nineteen volunteers (n=19), considered as statistical blocks, used an intraoral appliance containing the specimens, for 7 days. Enamel roughness (Ra) was tested before and after treatment, and after saliva exposure. Confocal laser scanning microscopy (CLSM) was used to evaluate qualitatively the enamel morphology. RESULTS: All groups exhibited increased Ra after microabrasion. With regards to saliva exposure, the treatment with HCl+Sil presented more susceptibility to the saliva action, but no period of time was efficient in re-establishing this characteristic compared with the control group. CLSM analysis showed reduction of the micro-abrasive damages during the experimental times. CONCLUSIONS: Seven days of saliva exposure were not sufficient for the treated enamel to reach its normal characteristics compared with the control group.

  18. In-situ performance evaluation of radon measurement techniques in Uranium mine exhausts of Jaduguda

    International Nuclear Information System (INIS)

    Several techniques are used for the measurement of the activity concentration of radon in the work place and the environment. Devices like Scintillation cell, Alpha guard and Low Level Radon Detection System (LLRDS) are widely used for the estimation of radon. Some of the devices like scintillation cell is normally used in high activity concentration, whereas, device like LLRDS is used in low activity concentration range. All these above devices are used in ambient mode in which air sample is either collected in a cell or in a chamber and the alpha counts are recorded after a definite delay. In some device, air is allowed to be diffused through a filter and alpha activity is estimated using proper detection system. Passive radon dosimeters can effectively be used both in low and high activity concentration range. The cumulative radon exposure can be assessed using passive radon dosimeters. For in situ performance evaluation an area is required where both high and low level activity concentration of radon is anticipated. Uranium mines exhaust area is presumed to be an area where both these conditions can be found by mere variation in the placement of the device. Inter comparison exercise can also be done effectively at this location using various devices of radon estimation

  19. Model predictions of metal speciation in freshwaters compared to measurements by in situ techniques.

    Science.gov (United States)

    Unsworth, Emily R; Warnken, Kent W; Zhang, Hao; Davison, William; Black, Frank; Buffle, Jacques; Cao, Jun; Cleven, Rob; Galceran, Josep; Gunkel, Peggy; Kalis, Erwin; Kistler, David; Van Leeuwen, Herman P; Martin, Michel; Noël, Stéphane; Nur, Yusuf; Odzak, Niksa; Puy, Jaume; Van Riemsdijk, Willem; Sigg, Laura; Temminghoff, Erwin; Tercier-Waeber, Mary-Lou; Toepperwien, Stefanie; Town, Raewyn M; Weng, Liping; Xue, Hanbin

    2006-03-15

    Measurements of trace metal species in situ in a softwater river, a hardwater lake, and a hardwater stream were compared to the equilibrium distribution of species calculated using two models, WHAM 6, incorporating humic ion binding model VI and visual MINTEQ incorporating NICA-Donnan. Diffusive gradients in thin films (DGT) and voltammetry at a gel integrated microelectrode (GIME) were used to estimate dynamic species that are both labile and mobile. The Donnan membrane technique (DMT) and hollow fiber permeation liquid membrane (HFPLM) were used to measure free ion activities. Predictions of dominant metal species using the two models agreed reasonably well, even when colloidal oxide components were considered. Concentrations derived using GIME were generally lower than those from DGT, consistent with calculations of the lability criteria that take into account the smaller time window available forthe fluxto GIME. Model predictions of free ion activities generally did not agree with measurements, highlighting the need for further work and difficulties in obtaining appropriate input data. PMID:16570619

  20. Stability and Reactive Power Compensation Techniques in Wind Farm

    Directory of Open Access Journals (Sweden)

    Kadam D.P

    2014-02-01

    Full Text Available Wind energy’s presence in the electric power system has dramatically grown over the past decade and will continue to grow worldwide as many countries have planned future developments. Large number of wind turbines are being installed and connected to power systems. In some of the countries the penetration of wind power is significant high so as to affect the power quality, system operation and control and power system stability. In this paper an attempt is made to predict the reactive power burden of the wind farm based on conventional fixed speed induction generator during wind variation and fault condition. PSCAD/EMTDC based large scale wind farm model is developed where STATCOM is introduced as an active voltage and reactive power supporter to increase the power system stability. STATCOM unit injects reactive power to mitigate power quality problems and to get stable grid operation.

  1. Synthesis of magnesia stabilized zirconia by co-precipitation technique

    International Nuclear Information System (INIS)

    The demand for new structural elements possessing a combination of properties such as good strength retention at high temperatures and high resistance to corrosion that find application in nuclear, aerospace, fuel cells etc., have led to the development of new materials as well as improvement in existing materials. Among the important development in the later direction is the synthesis of Stabilized Zirconia. This paper deals with the synthesis of oxide powders of magnesia stabilized zirconia used for high temperature applications mentioned above. Salts of zirconium oxy chloride and magnesium chloride were used as the precursors. The process involved controlled reaction of an aqueous solution of ammonium hydroxide into a solution containing zirconium oxy chloride and magnesium chloride. The resulting solution was filtered, dried and calcined. XRD, SEM/EDAX analyses were done and the results are reported. Variation of conductivity with temperature has also been studied. (author)

  2. The stability of chalk during flooding of carbonated sea water at reservoir in-situ conditions

    Science.gov (United States)

    Nermoen, Anders; Korsnes, Reidar I.; Madland, Merete V.

    2014-05-01

    Injection of CO2 into carbonate oil reservoirs has been proposed as a possible utilization of the captured CO2 due to its capability to enhance the oil recovery. For offshore reservoirs such as Ekofisk and Valhall it has been discussed to alternate the CO2 and sea water injection (WAG) to reduce costs and keep the beneficial effects of both sea water (SSW) and gas injection. Water and CO2 mix to form carbonic acids that enhance the solubility of carbonates, thus a serious concern has been raised upon the potential de-stabilization of the reservoirs during CO2 injection. In this study we focus on how carbonated sea water alters the mechanical integrity of carbonate rocks both to evaluate safety of carbon storage sites and in the planning of production strategies in producing oil fields since enhanced compaction may have both detrimental and beneficial effects. Here we will present results from long term experiments (approx. half year each) performed on Kansas outcrop chalk (38-41% porosity), which serves as model material to understand the physical and chemical interplaying processes taking place in chalk reservoirs. All tests are performed at uni-axial strain conditions, meaning that the confining radial stresses are automatically adjusted to ensure zero radial strain. The tests are performed at in-situ conditions and run through a series of stages that mimic the reservoir history at both Ekofisk and Valhall fields. We observe the strain response caused by the injected brine. The experimental stages are: (a) axial stress build-up by pore pressure depletion to stresses above yield with NaCl-brine which is inert to the chalk; (b) uni-axial creep at constant axial stresses with NaCl-brine; (c) sea water injection; and (d) injection of carbonated water (SSW+CO2) at various mixture concentrations. Two test series were performed in which the pore pressure was increased (re-pressurized) before stage (c) to explore the stress dependency of the fluid induced strain triggering. The main findings of our investigations are: 1. The creep rate in the plastic phase is pore fluid dependent. The injection of sea water induces a period of accelerating creep. 2. The injection of CO2 and sea water reduces the deformation rate, a result which is in contrast to what has previously been shown. 3. The solid weight of the plugs is maintained during flooding which indicates that the observed carbonate dissolution at the inlet side is counteracted with secondary precipitation, possibly calcium sulphate, within the plug. These recent obtained results show that chalk cores maintain their mechanical integrity during flooding of carbonated water. This experimental study, however, separates from earlier studies by the low injection rate which allows secondary precipitation processes to equilibrate within the plugs, chalk type, test temperature, and stress conditions, which all are factors that will affect the reported dynamics.

  3. Stabilization, Selection, and Tracking of Unstable Patterns by Fourier Space Techniques

    Science.gov (United States)

    Martin, R.; Scroggie, A. J.; Oppo, G.-L.; Firth, W. J.

    1996-11-01

    A new method for the stabilization and manipulation of unstable states of a pattern forming system is presented. The technique is applied to an optical system where unstable homogeneous solutions, rolls, squares, hexagons, and honeycombs are all stabilized and tracked. The control consists of a small spatial modulation to the input pump field, which is derived from the Fourier transform of the output electric field. Once stabilization is achieved, the control vanishes. The method can be used as a numerical tool for pattern forming systems to determine the existence and stability of solutions.

  4. Dimensional stability of a novel polyvinyl siloxane impression technique

    Scientific Electronic Library Online (English)

    Moira Pedroso, Leão; Camila Paloma, Pinto; Ana Paula, Sponchiado; Bárbara Pick, Ornaghi.

    2014-04-01

    Full Text Available AIM: To introduce a modification of the reline impression technique (MRIT), and compare the dimensional changes of impressions obtained by MRIT and by conventional reline impression technique (CRIT). METHODS: An acrylic resin tablet was milled by a CAD-CAM system to simulate three abutments (A [...] , B and C) with different distances among them. The abutments were molded using both impression techniques. For MRIT, before completing the putty silicone polymerization, the relieve procedure was made by compression and it was immediately repositioned to complete the polymerization. Impressions were stored dry at room temperature for different periods (immediately, 1 h, 2 days and 7 days). The distances were obtained by scanning. The differences between the impressions and their respective matrix reference measurements were calculated to determine the dimensional changes. Data were subjected to ANOVA and Tukey's test (p

  5. Evaluation of some by-Products using In situ and In vitro Gas Production Techniques

    Directory of Open Access Journals (Sweden)

    Besharati Maghsoud

    2008-01-01

    Full Text Available Food by-products in Iran are produced in high levels. In this study, in situ and in vitro gas production techniques were used to describe nutritive value of apple pomace, tomato pomace and noodle waste. For this purpose two ruminal fistulated sheep were used. Nylon bags which were approximately (6×12 cm containing 5 g samples (2 mm screen were incubated in duplicate in the rumen of fistulated sheep for 0,2,4,6,8,12,16,24,36 and 48 h. The gas production was recorded after 2, 4, 6, 8, 12, 16, 24, 36 and 48 h of incubation and the equation of P = A (1-e-ct was used to describe the kinetics of gas production. The data was analyzed using completely randomized design. DM and CP disappearance were significantly different among feedstuffs (p<0.05. After 48 h of incubation DM disappearance in noodle waste was highest and in tomato pomace was lowest. Regarding to the results, at the most incubation times tomato pomace had lower CP disappearance among feedstuffs (p<0.05. Potential gas production (A and rates of gas production (c differed among feedstuffs. Apple pomace showed higher potential gas production (A (305.1 mL g?1 DM and tomato pomace had higher rate of gas production (c (0.09 h?1 than the other feedstuffs. According to gas production volume, the value for the ME, OMD and SCFA ranged from in 8.87 noodle waste to 9.76 in apple pomace, 56.1 in tomato pomace to 64.3 in apple pomace and 0.919 in noodle waste to 1.168 in apple pomace, respectively. Partitioning factor in noodle waste was highest and in tomato pomace was lowest. In the present study, feeds composition significantly affected the degradation parameters.

  6. Simultaneous in situ Optical Monitoring Techniques during Crystal Growth of ZnSe by Physical Vapor Transport

    Science.gov (United States)

    Su, C.- H.; Feth, S.; Lehoczky, S. L.

    1998-01-01

    ZnSe crystals grown in sealed ampoules by the physical vapor transport method were monitored in situ using three techniques, simultaneously. A Michelson interferometer was set-up to observe the growth rate and surface morphological evolution. An interference pattern (interferogram) is formed by the interaction between the reflection of a HeNe laser (632.8 nm wavelength) off the crystal-vapor interface and a reference beam from the same laser. Preliminary results indicate that the rate of growth/thermal-etching can be calculated using analog data acquisition and simple fringe counting techniques. Gross surface features may also be observed using a digital frame grabber and fringe analysis software. The second in situ technique uses optical absorption to determine the partial pressures of the vapor species. The Se2 and Zn vapor species present in the sealed ampoule absorb light at characteristic wavelengths. The optical absorption is determined by monitoring the light intensity difference between the sample and reference beams. The Se2 Partial pressure profile along the length of the ampoule was estimated from the vibronic absorption peaks at 340.5, 350.8, 361.3 and 379.2 nm using the Beer's law constants established in the calibration runs of pure Se. Finally, because the high temperature crystal growth furnace contains windows, in situ visual observation of the growing crystal is also possible. The use of these techniques not only permits in situ investigation of high temperature vapor growth of semiconductors, but also offers the potential for real time feed back on the growing crystal and allows the possibility of actively controlling the growth process.

  7. Styrene grafted natural rubber reinforced by in situ silica generated via sol–gel technique

    Energy Technology Data Exchange (ETDEWEB)

    Sittiphan, Torpong [Program of Petrochemistry and Polymer Sciences, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand); Prasassarakich, Pattarapan [Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand); Poompradub, Sirilux, E-mail: sirilux.p@chula.ac.th [Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand)

    2014-02-15

    Highlights: • Sol–gel reaction by NR latex was the absence of use of organic solvent and base catalyst. • Well dispersed in situ formed silica particles in the rubber matrix were obtained. • In situ silica was better to improve mechanical properties of rubber vulcanizates. -- Abstract: The filling of styrene graft natural rubber (ST-GNR) with in situ formed silica was performed using the sol–gel reaction via the latex solution method. The mechanical properties of ST-GNR/NR vulcanizate were improved when using the in situ formed silica to levels higher than those obtained with the commercial ex situ formed silica filled ST-GNR/NR vulcanizates at a comparable silica content of 12 parts by weight per hundred parts of rubber. Transmission electron microscopy analysis revealed that the in situ silica particles were small (?40 nm diameter) and well dispersed, while the commercial silica particles were larger (?60 nm diameter) and markedly agglomerated in the rubbery matrix. The mechanical properties of the composites prepared via both the solid rubber and latex solution methods were comparable.

  8. Styrene grafted natural rubber reinforced by in situ silica generated via sol–gel technique

    International Nuclear Information System (INIS)

    Highlights: • Sol–gel reaction by NR latex was the absence of use of organic solvent and base catalyst. • Well dispersed in situ formed silica particles in the rubber matrix were obtained. • In situ silica was better to improve mechanical properties of rubber vulcanizates. -- Abstract: The filling of styrene graft natural rubber (ST-GNR) with in situ formed silica was performed using the sol–gel reaction via the latex solution method. The mechanical properties of ST-GNR/NR vulcanizate were improved when using the in situ formed silica to levels higher than those obtained with the commercial ex situ formed silica filled ST-GNR/NR vulcanizates at a comparable silica content of 12 parts by weight per hundred parts of rubber. Transmission electron microscopy analysis revealed that the in situ silica particles were small (?40 nm diameter) and well dispersed, while the commercial silica particles were larger (?60 nm diameter) and markedly agglomerated in the rubbery matrix. The mechanical properties of the composites prepared via both the solid rubber and latex solution methods were comparable

  9. Empleo de la técnica hibridación in situ fluorescente para visualizar microorganismos / Use of fluorescence in situ hybridization technique to visualize microorganisms

    Scientific Electronic Library Online (English)

    Raúl, Rodríguez Martínez.

    2011-12-01

    Full Text Available La hibridación in situ fluorescente (FISH), es una técnica que emplea sondas de oligonucleótidos marcadas con fluorocromos las cuales van dirigidas hacia secuencias específicas del ácido ribonucleico ribosomal (ARNr), lo que permite la identificación rápida y específica de células microbianas ya sea [...] que estén como células individuales o se encuentren agrupadas en su ambiente natural. El conocimiento de la composición y distribución de los microorganismos en los hábitats naturales, proporciona un soporte sólido para comprender la interacción entre las diversas especies que componen el micro hábitat. El objetivo de la revisión es presentar la forma como ha evolucionado la hibridación, el empleo del ARNr como molécula diana, los tipos de marcaje, los marcadores fluorescentes empleados hoy en día, la metodología, así como las mejoras que se le han hecho a la técnica FISH al emplearse en conjunto con otras técnicas en la identificación microbiana. Salud UIS 2011; 43 (3): 307-316 Abstract in english Fluorescence in situ hybridization (FISH), is a technique that uses oligonucleotides probes labeled with fluorochromes which are directed to specific sequences of ribosomal ribonucleic acid (rRNA), this allows the rapid and specific identification of microbial cells whether as individual cells or gr [...] ouped cells in their natural environment. Knowledge of the composition and distribution of microorganisms in natural habitats provides a solid support to understand interaction between different species in the microhabitat. This review shows how hybridization has evolved, the use of rRNA as target molecule, the type of labeling, the labeled uses today in fluorescent and the methodology, as well as the improvements that have been made to the FISH technique when is used in conjunction with other techniques in microbial identification. Salud UIS 2011; 43 (3): 307-316

  10. Techniques for assessing the performance of in situ bioreduction and immobilization of metals and radionuclides in contaminated subsurface environments

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, P.M.; Watson, D.B.; Blake, D.A.; Beard, L.P.; Brooks, S.C.; Carley, J.M.; Criddle, C.S.; Doll, W.E.; Fields, M.W.; Fendorf, S.E.; Geesey, G.G.; Ginder-Vogel, M.; Hubbard, S.S.; Istok, J.D.; Kelly, S.; Kemner, K.M.; Peacock, A.D.; Spalding, B.P.; White, D.C.; Wolf, A.; Wu, W.; Zhou, J.

    2004-11-14

    Department of Energy (DOE) facilities within the weapons complex face a daunting challenge of remediating huge below inventories of legacy radioactive and toxic metal waste. More often than not, the scope of the problem is massive, particularly in the high recharge, humid regions east of the Mississippi river, where the off-site migration of contaminants continues to plague soil water, groundwater, and surface water sources. As of 2002, contaminated sites are closing rapidly and many remediation strategies have chosen to leave contaminants in-place. In situ barriers, surface caps, and bioremediation are often the remedial strategies of chose. By choosing to leave contaminants in-place, we must accept the fact that the contaminants will continue to interact with subsurface and surface media. Contaminant interactions with the geosphere are complex and investigating long term changes and interactive processes is imperative to verifying risks. We must be able to understand the consequences of our action or inaction. The focus of this manuscript is to describe recent technical developments for assessing the performance of in situ bioremediation and immobilization of subsurface metals and radionuclides. Research within DOE's NABIR and EMSP programs has been investigating the possibility of using subsurface microorganisms to convert redox sensitive toxic metals and radionuclides (e.g. Cr, U, Tc, Co) into a less soluble, less mobile forms. Much of the research is motivated by the likelihood that subsurface metal-reducing bacteria can be stimulated to effectively alter the redox state of metals and radionuclides so that they are immobilized in situ for long time periods. The approach is difficult, however, since subsurface media and waste constituents are complex with competing electron acceptors and hydrogeological conditions making biostimulation a challenge. Performance assessment of in situ biostimulation strategies is also difficult and typically requires detailed monitoring of coupled hydrological, geochemical/geophysical, and microbial processes. In the following manuscript we will (1) discuss contaminant fate and transport problems in humid regimes, (2) efforts to immobilize metals and radionuclides in situ via bioremediation, and (3) state-of-the-art techniques for assessing the performance of in situ bioreduction and immobilization of metals and radionuclides. These included (a) in situ solution and solid phase monitoring, (b) in situ and laboratory microbial community analysis, (c) noninvasive geophysical methods, and (d) solid phase speciation via high resolution spectroscopy.

  11. Monitoring of cement stabilized surrogate waste using resonant frequency techniques

    International Nuclear Information System (INIS)

    It is often necessary to track incremental changes in the physical properties of composites with portland cement binders caused by chemical attack, freeze-thaw cycles, and other deterioration mechanisms. The vibration testing procedure presented for measuring the resonant frequency of a specimen is directly applicable to the monitoring of the deterioration of stabilized/solidified waste specimens. The change in the fundamental frequency is significantly more sensitive than the loss of mass to the internal changes in the mechanical properties of specimens. The time and effort required to determine the fundamental frequency of a specimen is also significantly less than that required to determine the loss of mass of the same specimen. The proposed method has been demonstrated to work on small cylindrical specimens (44 mm by 74 mm) with aspect ratios less than 2.0. The use of elastomeric bands as the means of attachment of the specimen to the test equipment does not interfere with or limit other chemical and mechanical performance tests scheduled for the specimens

  12. Development of the DGT technique for in-situ Pu speciation measurements

    International Nuclear Information System (INIS)

    Toxic effects of artificial radionuclides are strongly dependent on the surrounding chemical environment which determines the bioavailability of contaminant species. Speciation of plutonium in the environment is of particular interest since it is a long-life actinide contributing to the dose exposure via ingestion with water and food in case of radioactive discharge. Furthermore, natural colloids present in waters, as main carriers of dissolved trace metals, can transport plutonium over significant distances from contaminated sites. The diffusive gradients in thin films (DGT) technique is an efficient instrument for passive sampling of trace metals. It allows for in-situ monitoring of mean concentrations of bioavailable contaminant species (1). A DGT sampler consists of two gel layers: a polyacrylamide hydrogel diffusion layer allowing to diffuse labile metal species to the second, binding layer, impregnated with ion-exchange resin. Resin elution and further analysis allow determining the amount of the bioavailable fraction of trace metals in the bulk solution, which can be calculated from the relationship: Cbulk= (M x ?g)/(D x t x A) where M is the measured metal species inventory in the resin, ?g the thickness of the diffusion layer, D the diffusion coefficient of the species in the gel, t the time of deployment, A the diffusion area. To our knowledge, the DGT has not yet been applied for Pu speciation measurements and the D value is unknown. Here we propose the use of DGT to monitor the dissolved phase and labile complexes of plutonium in the aquatic environment. We have first measured the diffusion coefficient of plutonium in the hydrogel. Experiments were carried out in a diffusion cell (2) and with commercially available DGT samplers exposed in standardized solutions containing 239Pu at pico-molar concentrations. Both approaches give comparable D values in the range of 2.30 x 10-6 - 2.45 x 10-6 cm2 s-1. We then studied plutonium diffusion in the presence of naturally occurring ligands - fulvic and humic acids - and in natural waters sampled at a mineral spring and an organic-rich brook of a karst system in the Swiss Jura Mountains, in which the increased mobility of 239+240Pu compared to 241Am and 137Cs has been recently observed (3). Diffusion experiments in simulated natural conditions show different mobility of the radionuclide in fresh waters with different DOM content, supporting the idea that the speciation of plutonium and the abundance of free ionic form in particular, are of prime importance to better estimate the bioavailability and the toxicity of plutonium. (authors)

  13. Development of the DGT technique for in-situ Pu speciation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Cusnir, R.; Bochud, F.; Froidevaux, P. [Institute of Radiation Physics, Lausanne University Hospital, Rue du Grand-Pre 1, CH-1007 Lausanne (Switzerland); Steinmann, P. [Federal Office of Public Health, Swarzenburgstrasse 165, CH-3003 Bern (Switzerland)

    2014-07-01

    Toxic effects of artificial radionuclides are strongly dependent on the surrounding chemical environment which determines the bioavailability of contaminant species. Speciation of plutonium in the environment is of particular interest since it is a long-life actinide contributing to the dose exposure via ingestion with water and food in case of radioactive discharge. Furthermore, natural colloids present in waters, as main carriers of dissolved trace metals, can transport plutonium over significant distances from contaminated sites. The diffusive gradients in thin films (DGT) technique is an efficient instrument for passive sampling of trace metals. It allows for in-situ monitoring of mean concentrations of bioavailable contaminant species (1). A DGT sampler consists of two gel layers: a polyacrylamide hydrogel diffusion layer allowing to diffuse labile metal species to the second, binding layer, impregnated with ion-exchange resin. Resin elution and further analysis allow determining the amount of the bioavailable fraction of trace metals in the bulk solution, which can be calculated from the relationship: C{sub bulk}= (M x ?g)/(D x t x A) where M is the measured metal species inventory in the resin, ?g the thickness of the diffusion layer, D the diffusion coefficient of the species in the gel, t the time of deployment, A the diffusion area. To our knowledge, the DGT has not yet been applied for Pu speciation measurements and the D value is unknown. Here we propose the use of DGT to monitor the dissolved phase and labile complexes of plutonium in the aquatic environment. We have first measured the diffusion coefficient of plutonium in the hydrogel. Experiments were carried out in a diffusion cell (2) and with commercially available DGT samplers exposed in standardized solutions containing {sup 239}Pu at pico-molar concentrations. Both approaches give comparable D values in the range of 2.30 x 10{sup -6} - 2.45 x 10{sup -6} cm{sup 2} s{sup -1}. We then studied plutonium diffusion in the presence of naturally occurring ligands - fulvic and humic acids - and in natural waters sampled at a mineral spring and an organic-rich brook of a karst system in the Swiss Jura Mountains, in which the increased mobility of {sup 239+240}Pu compared to {sup 241}Am and {sup 137}Cs has been recently observed (3). Diffusion experiments in simulated natural conditions show different mobility of the radionuclide in fresh waters with different DOM content, supporting the idea that the speciation of plutonium and the abundance of free ionic form in particular, are of prime importance to better estimate the bioavailability and the toxicity of plutonium. (authors)

  14. Electrochemical and spectroscopic in situ techniques for the investigation of the phosphating of zinc coated steel

    International Nuclear Information System (INIS)

    In this work spectroscopic and electrochemical techniques were developed for the investigation of surface treatments used in steel industry. ICP-atomic emission spectroscopy (ICP-AES), Raman spectroscopy and the Quartz crystal microbalance (QCM) were applied to the investigation of the kinetics of phosphating as well as the properties of phosphate layers. Phosphating of zinc coated steel leads to the formation of a crystalline layer consisting of zinc phosphate and is employed to enhance paint adhesion and corrosion protection. For the high reaction rates necessary in industrial production lines, oxidation agents are added to the phosphating bathes to accelerate the reaction. The oxidation agents provide an additional reduction reaction beside the hydrogen formation and therefore decrease the number of gas bubbles, which would block the zinc surface and reduce the rate of phosphating. With addition of H2O2 or nitrates the rate of layer formation is distinctly increased. In a combined experiment of ICP-AES with QCM and potential transients, it was shown that the presence of these accelerators in the phosphating bath increases the rate of zinc dissolution and hence leads to a faster formation of the phosphate layer. In under paint corrosion of painted, zinc coated steel phosphate layers are exposed to a highly alkaline environment. The stability of a phosphate layer against alkaline attack is therefore essential for its performance in corrosion protection. To enhance thnce in corrosion protection. To enhance the alkaline stability Mn and Ni are added to modern phosphating bathes. The incorporation of these elements reduces the dissolution rate in 0.1 M NaOH proportional to their concentration in the phosphate layer. The dissolution of Zn, P, Mn and Ni was determined quantitatively with ICP-AES. Raman spectroscopy showed the formation of a Mn-hydroxide layer during alkaline attack, which protects the phosphate layer and reduces further dissolution. On basis of these results the reaction of phosphate layers with alkaline solution can be proposed as an ion-exchange of PO43- and OH- resulting in a mixed hydroxide consisting of Zn and Mn. The model of the reaction mechanism was confirmed by additional QCM experiments. (author)

  15. A Genetic Algorithm-based Technique to Enhance H? Controller: Stabilizes Acceleration in PMSM

    Directory of Open Access Journals (Sweden)

    T.S. Viswanath

    2010-12-01

    Full Text Available In recent years, a high class evolution has been achieved by control systems in different application areas. Acceleration control in Permanent Magnet Synchronous Motor is one among the noteworthy applications of evolving control systems. Though numerous methodologies have been proposed in the literature, they perform thecontrol operations statically. Moreover, controllers are very rarely used for this purpose. This leads to the problem of delayed stability in the acceleration/velocity control of Permanent Magnet Synchronous Motor. In this paper, a Genetic Algorithm-based technique is proposed to accomplish effective stability in Permanent Magnet Synchronous Motor controlling operations. This technique introduces multiples of rotor mass (considered without load, along with the system parameters. A GA-based optimization is performed over the considered system parameters and so acceleration achieves stability in a very short time. The proposed technique is tested with a standard ? H problem and the results are evaluated by comparing them with that of an existing H-infinity control technique. The implementation results have shown that the proposed technique achieves stability of acceleration as well as velocity in a much shorter time compared to the existing technique.

  16. In situ transmission FTIR spectroelectrochemistry: A new technique for studying lithium batteries

    International Nuclear Information System (INIS)

    In situ transmission FTIR spectra are measured during the electrochemical insertion of lithium into phospho-olivine FePO4. The spectroelectrochemical cell consists of a composite FePO4 cathode, a lithium metal anode, and an electrolyte of 1 M LiPF6 in a 1:1 mixture of ethylene carbonate and diethyl carbonate (EC-DEC). Bands belonging to the electrolyte and cathode are identified in the infrared spectra of the in situ cells. The antisymmetric PO4 3- bending vibrations (?4) are used to monitor Li+ insertion into FePO4. Discharging produces spectral changes that are consistent with the formation of phospho-olivine LiFePO4, yet the electrolyte bands are not affected by the discharging process. The in situ infrared experiments confirm the two-phase mechanism for lithium insertion into FePO4. Moreover, the experiments demonstrate the ability to collect in situ transmission FTIR spectra of functioning electrode materials in lithium batteries. Unfortunately, lithium plating occurs on the optical window when the Li//FePO4 half-cells are charged. The use of an intercalation anode such as graphite could alleviate this problem; however, this avenue of research is not explored in this study

  17. In situ transmission FTIR spectroelectrochemistry: A new technique for studying lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Burba, Christopher M.; Frech, Roger [University of Oklahoma, Norman, OK (United States). Department of Chemistry and Biochemistry

    2006-11-12

    In situ transmission FTIR spectra are measured during the electrochemical insertion of lithium into phospho-olivine FePO{sub 4}. The spectroelectrochemical cell consists of a composite FePO{sub 4} cathode, a lithium metal anode, and an electrolyte of 1M LiPF{sub 6} in a 1:1 mixture of ethylene carbonate and diethyl carbonate (EC-DEC). Bands belonging to the electrolyte and cathode are identified in the infrared spectra of the in situ cells. The antisymmetric PO{sub 4}{sup 3-} bending vibrations (n{sub 4}) are used to monitor Li{sup +} insertion into FePO{sub 4}. Discharging produces spectral changes that are consistent with the formation of phospho-olivine LiFePO{sub 4}, yet the electrolyte bands are not affected by the discharging process. The in situ infrared experiments confirm the two-phase mechanism for lithium insertion into FePO{sub 4}. Moreover, the experiments demonstrate the ability to collect in situ transmission FTIR spectra of functioning electrode materials in lithium batteries. Unfortunately, lithium plating occurs on the optical window when the Li//FePO{sub 4} half-cells are charged. The use of an intercalation anode such as graphite could alleviate this problem; however, this avenue of research is not explored in this study. (author)

  18. A novel fluorescent in situ hybridization technique for detection of Rickettsia spp. in archival samples

    DEFF Research Database (Denmark)

    Svendsen, Claus Bo; Boye, Mette

    2009-01-01

    A novel, sensitive and specific method for detecting Rickettsia spp. in archival samples is described. The method involves the use of fluorescently marked oligonucleotide probes for in situ hybridization. Specific hybridization of Ricekttsia was found without problems of cross-reactions with bacterial species shown to cross-react serologically.

  19. A New Meta-heuristic Technique Based on Robust Power System Stabilizer with Wind Power Penetrations

    Directory of Open Access Journals (Sweden)

    Vahid Sattarpoor

    2015-06-01

    Full Text Available In this paper a robust Power System Stabilizer (PSS is proposed based on inverse additive perturbation in a power system with wind farms. The  proposed controller designed by new Improve Bacteria Foraging Algorithm (IBFA to achieve robustness of this strategy where the optimization process is formulated based on an enhancement of system robust stability margin. The designed optimal PSS is based on Fuzzy Logic Controller (FLC. The effectiveness of the proposed technique is tested over ten macine 39 buses New England power system. Obtained results demonstrate the superiority of proposed technique over conventional PSS.

  20. Development of in-situ laser based cutting technique for shock absorber rear nut in pressurized heavy water reactors. CP-2.1

    International Nuclear Information System (INIS)

    We have developed a laser based cutting technique for shock absorber rear nuts in pressurized heavy water reactors (PHWRs). This technique has been successfully used for in-situ laser cutting at RAPS-3 reactor. The technique consists of a motorized compact fixture, which holds a fiber optic beam delivery cutting nozzle and can be operated remotely

  1. Stabilization of hydrogen peroxide used as oxidizing agent in the in-situ leaching of uranium from arkosic sandstone

    International Nuclear Information System (INIS)

    H/sub 2/O/sub 2/ was used as oxidizing agent of the insoluble tetravalent uranium into the soluble hexavalent state along with NH/sub 4/HCO/sub 3/as complexing agent in tap water solvent. The study was conducted to look at the possibility of commercial scale in situ leaching of uranium from an underground arkosic sandstone ore deposit. It was found that the peroxide was unstable in the basic tap water solvent as well as in the lixiviants to be used for uranium leaching, especially, in the presence of Ca ions and NH/sub 4/HCO/sub 3/. The rate of dissipation of the oxidizing agent was studied in different media at room temperature for 192 hours with distilled water as a reference medium. The material was stabilized by complexing the different ions / metal catalysts in the lixiviant by EDTA. In the presence of EDTA the stability behaviour of the peroxide became almost identical in the distilled water and tap water lixiviants. (author)

  2. Structural stability of SiGe nanoparticles under 'in situ' electron beam irradiation in TEM

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, M I; Kanyinda-Malu, C; Ballesteros, C [epartamento de Fisica, E. P. S, Universidad Carlos III de Madrid, Avda. Universidad 30, 28911 Leganes, Madrid (Spain); Rodriguez, A; Sangrador, J; Rodriguez, T [Departamento de TecnologIa Electronica, E.T.S.I. de Telecomunicacion, Universidad Politecnica de Madrid, 28040 Madrid (Spain)], E-mail: balleste@fis.uc3m.es

    2008-08-15

    The structure of amorphous and crystalline SiGe nanoparticles, embedded in a dielectric medium, SiO{sub 2}, and its stability under 'in situ' electron beam irradiation is reported. High-resolution transmission electron microscopy and electron-diffraction pattern simulation by fast Fourier transform was used to analyze the crystal structure of the SiGe nanoparticles. Electron beam irradiation induces structural alternate order-disorder transitions in the nanoparticles for irradiation effects are mainly associated to the density of current. For irradiation with current densities < 7 A.cm-{sup -2} no effects are observed in the as-deposited amorphous samples, whereas in the crystallized samples, SiGe nanocrystals show higher stability and no effects are observed for irradiation densities of current < 50 A-cm{sup -2}. Irradiation with densities of current greater than these thresholds cause consecutive amorphous-crystalline or crystalline-amorphous structure transitions respectively for both amorphous and crystallized nanoparticles. A hexagonal structure is proposed for those nanocrystals obtained after irradiation in the as deposited amorphous samples.

  3. In-situ measurements of the radiation stability of amino acids at 15-140 K

    CERN Document Server

    Gerakines, P A; Moore, M H; Bell, J -L

    2015-01-01

    We present new kinetics data on the radiolytic destruction of amino acids measured in situ with infrared spectroscopy. Samples were irradiated at 15, 100, and 140 K with 0.8-MeV protons, and amino-acid decay was followed at each temperature with and without H$_2$O present. Observed radiation products included CO$_2$ and amines, consistent with amino-acid decarboxylation. The half-lives of glycine, alanine, and phenylalanine were estimated for various extraterrestrial environments. Infrared spectral changes demonstrated the conversion from the non-zwitterion structure NH$_2$-CH$_2$(R)-COOH at 15 K to the zwitterion structure $^+$NH$_3$-CH$_2$(R)-COO$^-$ at 140 K for each amino acid studied.

  4. In-Situ Measurements of the Radiation Stability of Amino Acids at 15-140 K

    Science.gov (United States)

    Gerakines, Perry A.; Hudson, Reggie L.; Moore, Marla H.; Bell, Jan-Luca

    2012-01-01

    We present new kinetics data on the radiolytic destruction of amino acids measured in situ with infrared spectroscopy. Samples were irradiated at 15, 100, and 140 K with D.8-MeV protons, and amino-acid decay was followed at each temperature with and without H2O present. Observed radiation products included CO2 and amines, consistent with amino-acid decarboxylation. The half-lives of glycine, alanine, and phenylalanine were estimated for various extraterrestrial environments. Infrared spectral changes demonstrated the conversion from the non-zwitterion structure NH2-CH2(R)-COOH at 15 K to the zwitterion structure +NH3-CH2(R)-COO- at 140 K for each amino acid studied.

  5. Stabilization of ambient sensitive atomic layer deposited lanthanum aluminates by annealing and in situ capping

    Science.gov (United States)

    Swerts, J.; Gielis, S.; Vereecke, G.; Hardy, A.; Dewulf, D.; Adelmann, C.; Van Bael, M. K.; Van Elshocht, S.

    2011-03-01

    We have studied the effect of air exposure on lanthanum aluminates (LaAlOx) deposited by atomic layer deposition. Fourier transform infrared spectroscopy and thermal desorption spectroscopy of as-deposited LaAlOx showed that H2O is absorbed during air exposure and that the amount of absorbed H2O increases with increasing La atomic percent. C was found to be incorporated already during deposition in the form of carbonates. H2O and CO2 are outgassed during postdeposition annealing in an inert atmosphere. After a 700 °C postdeposition anneal, the LaAlOx becomes resistant against H2O absorption due to film densification. Alternatively, in situ capping of the LaAlOx with a ˜2 nm thin Al2O3 film protects the LaAlOx against H2O absorption, but it also hinders the outgassing of the C contaminants during a postdeposition anneal.

  6. Stability of Porous Platinum Nanoparticles: Combined In Situ TEM and Theoretical Study

    DEFF Research Database (Denmark)

    Chang, Shery L. Y.; Barnard, Amanda S.

    2012-01-01

    Porous platinum nanoparticles provide a route for the development of catalysts that use less platinum without sacrificing catalytic performance. Here, we examine porous platinum nanoparticles using a combination of in situ transmission electron microscopy and calculations based on a first-principles-parametrized thermodynamic model. Our experimental observations show that the initially irregular morphologies of the as-sythesized porous nanoparticles undergo changes at high temperatures to morphologies having faceted external surfaces with voids present in the interior of the particles. The increasing size of stable voids with increasing temperature, as predicted by the theoretical calculations, shows excellent agreement with the experimental findings. The results indicate that hollow-structured nanoparticles with an appropriate void-to-total-volume ratio can be stable at high temperatures.

  7. Design of top covers supporting aerobic in situ stabilization of old landfills – An experimental simulation in lysimeters

    International Nuclear Information System (INIS)

    Highlights: ? Tested engineered covers as surrogate to gas extraction during and after in situ aeration. ? Examined how covers influence gas emissions, water balance and leachate generation. ? Investigated effect of top covers on air-distribution in waste mass during aeration. ? We suggest criteria and cover design to meet the demands during and after aeration. ? Such cover systems may offer greenhouse gas emission reduction also after active aeration. - Abstract: Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top covers that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 × 2 × 3 m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results revein situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH4 loadings up to 300 l CH4/m2 d. In addition, the compost material provided high air permeability even at 100% water holding capacity (WHC). In contrast, the more cohesive, mineral soil cover was expected to cause a notably uniform distribution of the injected air within the waste layer. Laboratory results also revealed sufficient air permeability of the soil materials (TS-F and SS-Z) placed in lysimeter C. However, at higher compaction density SS-Z became impermeable at 100% WHC. Methane emissions from the reference lysimeter with the smaller substrate cover (12–52 g CH4/m2 d) were significantly higher than fluxes from the other lysimeters (0–19 g CH4/m2 d) during in situ aeration. Regarding water balance, lysimeters covered with compost and compost-sand mixture, showed the lowest leachate rate (18–26% of the precipitation) due to the high water holding capacity and more favourable plant growth conditions compared to the lysimeters with mineral, more cohesive, soil covers (27–45% of the precipitation). On the basis of these results, the authors suggest a layered top cover system using both compost material as well as mineral soil in order to support active low-pressure aeration. Conventional soil materials with lower permeability may be used on top of the landfill body for a more uniform aeration of the waste due to an increased resistance to vertical gas flow. A compost cover may be built on top of the soil cover underlain by a gas distribution layer to improve methane oxidation rates and minimise water infiltration. By planting vegetation with a high transpiration rate, the leachate amount emanating from the landfill could be further minimised. The suggested design may be particularly suitable in combination with intermittent in situ aeration, in the later stage of an aeration measure, or at very small sites and shallow deposits. The top cover system could further regulate water infiltration into the landfill and mitigate residual CH4 emissions, even beyond the time of active aeration.

  8. Engineering feasibility analysis for in-situ stabilization of Burrell Township site residues

    International Nuclear Information System (INIS)

    The Burrell Township site, located in western Pennsylvania, received approximately 11,600 tons of radioactively-contaminated material in late 1956 and early 1957 from the Vitro Manufacturing Company's operations in Canonsburg, Pennsylvania. WESTON was requested to conduct an engineering study to determine the feasibility of stabilizing the site in accordance with the US Environmental Protection Agency's (EPA) interim and proposed standards (45 FR 27366--27368, April 22, 1980, and 46 FR 2556--2563, January 9, 1981). The scope of this study is limited to those alternatives that can be implemented on the site and will not require removal and offsite disposal of radioactively-contaminated material. Four alternatives for control of the radioactive material at the Burrell site were considered and evaluated, as follows: 1. Site stabilization and closure. 2. Site control and containment. 3. Waste excavation and encapsulation. 4. Waste excavation, incineration, and encapsulation. 2 refs., 32 figs., 12 tabs

  9. Thermal stability and surface behaviors of CeO2/Si films during in-situ vacuum annealing

    Science.gov (United States)

    Luo, Lizhu; Chen, Jun; Wang, Xiaolin

    2014-12-01

    CeO2 thin films were deposited on Si (1 1 1) substrates by laser molecular-beam epitaxy (LMBE). The thermal stability and surface behaviors of CeO2/Si samples were investigated by X-ray photoelectron spectroscopy during in-situ vacuum annealing. Temperature dependency of surface compositions was identified. At the temperature from 700 K to 1000 K, CeO2 was reduced gradually, but incomplete transformation of CeO2 to Ce2O3 was found even when the sample was annealed at 1000 K for an hour. When the sample was exposed to oxygen ambience, the enhanced thermal stability of the partially reduced surface was revealed by the slight variation of Ce3d and Ce4d spectra. Si2p peak at 102.7 eV was detected on the top surface after the whole heating treatments, while not for the sub-surface during sputtering till to the interface. The Si signal at the outmost surface is induced by surface segregation due to the decreasing solid solubility of Si atoms in CeO2 matrix with the decreasing temperature. At the interface, Si2p peaks at 99.9 eV with the presence of Ce4d peaks at 122.2 eV and 125.6 eV are attributed to the formation of cerium silicates with Ce-Si-O matrix during annealing due to interfacial reactions, which are supposed to stabilize the partially reduced ceria system.

  10. In situ applications of X ray fluorescence techniques. Final report of a coordinated research project 2000-2003

    International Nuclear Information System (INIS)

    In 2000 the IAEA initiated a Coordinated Research Project (CRP) on In Situ Applications of XRF Techniques as one of the elements of the project on Nuclear Instruments for Specific Applications, the major objective of which is to assist Member States in the development of nuclear instruments and software for special applications such as the characterization of materials. An overall objective of the CRP was to assist laboratories in Member States in such areas as environmental pollution monitoring, mineral exploration, the preservation of cultural heritage, the control of industrial processes and the optimization of analytical methodologies for these applications using field-portable X ray fluorescence (FPXRF). Although a significant amount of work has been undertaken in the development of FPXRF techniques, there is little consensus on the best approach for any particular application. The most important aspect before FPXRF techniques can be applied successfully is, therefore, the development of a clear FPXRF methodology. Because of the wide range of problems to which FPXRF can be applied, these procedures must be comprehensive and cover many applications involving the analysis of samples such as rocks, soils, air particulates or liquid samples. The specific research objectives of the CRP included the development and optimization of sampling methodologies for in situ XRF measurements, the improvement in the analytical performance of FPXRF based on the study of mineralogical effects, surface irregularity effects, heterogeneity and the influence of moisture content, the development and validation of quantitative and/or semi-quantitative procedures to be applied for in situ XRF analysis and development of complete operating procedures for selected in situ applications, including relevant quality assurance. The CRP covered a period of four years (2000?2003). Twelve laboratories from both developed and developing Member States and the IAEA?s Laboratories participated.This publication presents the results of the CRP. The IAEA officers responsible for the publication were A. Markowicz, D. Wegrzynek and K. Will of the Agency?s Laboratories, Seibersdorf. In the presented reports a summary of the work carried out by Member States and achievements at their laboratories related to the XRF and FPXRF techniques was given. The individual country reports are included in this publication. It was concluded that the participants carried out the research according to the agreed work plans and the objectives of the CRP were met. The following recommendations resulted from the CRP: Training courses in FPXRF analysis and in XRF data evaluation and interpretation are needed. Promotion of FPXRF spectrometry based on the advantages over other analytical techniques as applied for in situ soil analysis, geochemical prospecting, archaeometry and alloy identification is required. Regional Technical Cooperation projects are possible in order to improve implementation of XRF techniques in support of various areas of economy and development in the Member States. A database of certified standard reference materials applicable to XRF techniques is required. Development of dedicated FPXRF instruments for analysis of works of art and study of cultural heritage objects, environmental monitoring, etc., has to be continued. The Coordinated Research Project was very useful and cost effective. Therefore, further support of the XRF laboratories in Member States involved in research in the field of X ray fluorescence is required. Moreover, the uniqueness and potential applications of XRF techniques should be promoted. A new Coordinated Research Project in this field should be considered, e.g., focused on selected applications (such as environmental monitoring, archaeometry, material sciences or agriculture)

  11. Neutron capture gamma-ray technique for in situ mineral analysis

    International Nuclear Information System (INIS)

    The application of neutron capture gamma ray method for in situ analysis of mineral deposits is discussed. A borehole sonde for prompt gamma analysis (PGA) using a 3 Ci Americium-Berelium neutron source and a hyper pure germanium detector has been designed, constructed and evaluated. The evaluation program was designed to include neutron flux distribution in the simulated borehole, both experimentally and theoretically, response of the borehole sonde to elements of different concentrations and at different locations from the sonde, response of the sonde to dry borehole and to a water layer between the sonde and the borehole casing, and the response of the sonde to various elements in the matrix. The results indicate that the sonde is able to perform in situ multielement analysis for more than 20 elements. The extent of detection depends on elemental concentration and the other associated elements in the given matrix and to the water layer thickness between the sonde and the borehole casing. 39 refs

  12. Field Deployment for In-situ Metal and Radionuclide Stabilization by Microbial Metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Turick, C. E.; Knox, A. S.; Dixon, K. L.; Roseberry, R. J.; Kritzas, Y. G

    2005-09-26

    A novel biotechnology is reported here that was demonstrated at SRS that facilitates metal and actinide immobilization by incorporating the physiology and ecology of indigenous bacteria. This technology is based on our previous work with pyomelanin-producing bacteria isolated from SRS soils. Through tyrosine supplementation, overproduction of pyomelanin was achieved, which lead ultimately to metal and actinide immobilization, both in-vitro and in-situ. Pyomelanin is a recalcitrant microbial pigment and a humic type compound in the class of melanin pigments. Pyomelanin has electron shuttling and metal chelation capabilities and thus accelerates the bacterial reduction and/or immobilization of metals. Pyomelanin is produced outside the cell and either diffuses away or attaches to the cell surface. In either case, the reduced pyomelanin is capable of transferring electrons to metals as well as chelating metals. Because of its recalcitrance and redox cycling properties, pyomelanin molecules can be used over and over again for metal transformation. When produced in excess, pyomelanin produced by one bacterial species can be used by other species for metal reduction, thereby extending the utility of pyomelanin and further accelerating metal immobilization rates. Soils contaminated with Ni and U were the focus of this study in order to develop in-situ, metal bioimmobilization technologies. We have demonstrated pyomelanin production in soil from the Tims Branch area of SRS as a result of tyrosine amendments. These results were documented in laboratory soil column studies and field deployment studies. The amended soils demonstrated increased redox behavior and sequestration capacity of U and transition metals following pyomelanin production. Treatments incorporating tyrosine and lactate demonstrated the highest levels of pyomelanin production. In order to determine the potential use of this technology at other areas of SRS, pyomelanin producing bacteria were also quantified from metal contaminated soils at TNX and D areas of SRS. A bacterial culture collection from subsurface studies near P Area of SRS were also evaluated for pyomelanin production. Bacterial densities of pyomelanin producers were determined to be >10{sup 6} cells/g soil at TNX and D areas. In addition, approximately 25% of isolates from P area demonstrated pyomelanin production in the presence of tyrosine. Biogeochemical activity is an ongoing and dynamic process due, in part, to bacterial activity in the subsurface. Bacteria contribute significantly to biotransformation of metals and radionuclides. An understanding and application of the mechanisms of metal and radionuclide reduction offers tremendous potential for development into bioremedial processes and technologies. This report demonstrates the application of recent advances in bacterial physiology and soil ecology for future bioremediation activities involving metal and actinide immobilization.

  13. Deformation processes in functional materials studied by in-situ neutron diffraction and ultrasonic techniques.

    Czech Academy of Sciences Publication Activity Database

    Šittner, Petr; Novák, Václav; Landa, Michal; Lukáš, Petr

    2007-01-01

    Ro?. 462, - (2007), s. 12-22. ISSN 0921-5093 R&D Projects: GA AV ?R IAA1048107; GA ?R GA106/03/1073 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z10480505; CEZ:AV0Z20760514 Keywords : in situ neutron diffraction * ultrasonics * SMA * NiTi * phase transformations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.457, year: 2007

  14. In Situ Stability of Substrate-Associated Cellulases Studied by DSC

    DEFF Research Database (Denmark)

    Borch, Kim; Cruys-Bagger, Nicolaj

    2014-01-01

    This work shows that differential scanning calorimetry (DSC) can be used to monitor the stability of substrate-adsorbed cellulases during long-term hydrolysis of insoluble cellulose. Thermal transitions of adsorbed enzyme were measured regularly in subsets of a progressing hydrolysis, and the size of the transition peak was used as a gauge of the population of native enzyme. Analogous measurements were made for enzymes in pure buffer. Investigations of two cellobiohydrolases, Cel6A and Cel7A, from Trichoderma reesei, which is an anamorph of the fungus Hypocrea jerorina, showed that these enzymes were essentially stable at 25 °C. Thus, over a 53 h experiment, Cel6A lost less than 15% of the native population and Cel7A showed no detectable loss for either the free or substrate-adsorbed state. At higher temperatures we found significant losses in the native populations, and at the highest tested temperature (49 °C) about 80% Cel6A and 35% of Cel7A was lost after 53 h of hydrolysis. The data consistently showed that Cel7A was more long-term stable than Cel6A and that substrate-associated enzyme was less long-term stable than enzyme in pure buffer stored under otherwise equal conditions. There was no correlation between the intrinsic stability, specified by the transition temperature in the DSC, and the long-term stability derived from the peak area. The results are discussed with respect to the role of enzyme denaturation for the ubiquitous slowdown observed in the enzymatic hydrolysis of cellulose.

  15. A microfluidic electrochemical detection technique for assessing stability of thin films and emulsions.

    Science.gov (United States)

    Mostowfi, Farshid; Czarnecki, Jan; Masliyah, Jacob; Bhattacharjee, Subir

    2008-01-15

    An experimental technique is developed for assessing stability of thin liquid films by application of electric potential to compress the liquid film and to simultaneously measure the electrical properties of the system. The concept involves creating a thin film at the intersection of two microchannels etched onto a glass substrate. A ramped DC potential difference is applied across the film, which develops an electrical stress across the film. Increasing the potential to a critical value leads to the rupture of the film. The critical potential is used to assess the stability of the liquid film. Small channel dimensions in this microfluidic platform allow characterization of thin films formed between micron-sized droplets representing systems with high capillary pressures, analysis of which are typically beyond the scope of conventional thin film characterization techniques. The results of DC potential breakdown of films show that critical potential can be considered as a measure of thin film stability. PMID:17964591

  16. Design of top covers supporting aerobic in situ stabilization of old landfills - An experimental simulation in lysimeters

    Energy Technology Data Exchange (ETDEWEB)

    Hrad, Marlies [Institute of Waste Management, Department of Water-Atmosphere-Environment, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna (Austria); Huber-Humer, Marion, E-mail: marion.huber-humer@boku.ac.at [Institute of Waste Management, Department of Water-Atmosphere-Environment, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna (Austria); Wimmer, Bernhard; Reichenauer, Thomas G. [Health and Environment Department, Environmental Resources and Technologies, AIT Austrian Institute of Technology GmbH, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Tested engineered covers as surrogate to gas extraction during and after in situ aeration. Black-Right-Pointing-Pointer Examined how covers influence gas emissions, water balance and leachate generation. Black-Right-Pointing-Pointer Investigated effect of top covers on air-distribution in waste mass during aeration. Black-Right-Pointing-Pointer We suggest criteria and cover design to meet the demands during and after aeration. Black-Right-Pointing-Pointer Such cover systems may offer greenhouse gas emission reduction also after active aeration. - Abstract: Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top covers that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 Multiplication-Sign 2 Multiplication-Sign 3 m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH{sub 4} loadings up to 300 l CH{sub 4}/m{sup 2} d. In addition, the compost material provided high air permeability even at 100% water holding capacity (WHC). In contrast, the more cohesive, mineral soil cover was expected to cause a notably uniform distribution of the injected air within the waste layer. Laboratory results also revealed sufficient air permeability of the soil materials (TS-F and SS-Z) placed in lysimeter C. However, at higher compaction density SS-Z became impermeable at 100% WHC. Methane emissions from the reference lysimeter with the smaller substrate cover (12-52 g CH{sub 4}/m{sup 2} d) were significantly higher than fluxes from the other lysimeters (0-19 g CH{sub 4}/m{sup 2} d) during in situ aeration. Regarding water balance, lysimeters covered with compost and compost-sand mixture, showed the lowest leachate rate (18-26% of the precipitation) due to the high water holding capacity and more favourable plant growth conditions compared to the lysimeters with mineral, more cohesive, soil covers (27-45% of the precipitation). On the basis of these results, the authors suggest a layered top cover system using both compost material as well as mineral soil in order to support active low-pressure aeration. Conventional soil materials with lower permeability may be used on top of the landfill body for a more uniform aeration of the waste due to an increased resistance to vertical gas flow. A compost cover may be built on top of the soil cover underlain by a gas distribution layer to improve methane oxidation rates and minimise water infiltration. By planting vegetation with a high transpiration rate, the leachate amount emanating from the landfill could be further minimised. The suggested design may be particularly suitable in combination with intermittent in situ aeration, in the later stage of an aeration measure, or at very small sites and shallow deposits. The top cover system could further regulate water infiltration into the landfill and mitigate residual CH{sub 4} emissions, even beyond the time of active aeration.

  17. A comprehensive approach for the assessment of in-situ pavement density using GPR technique

    Science.gov (United States)

    Plati, Christina; Georgiou, Panos; Loizos, Andreas

    2013-04-01

    Proper construction of the asphalt pavement is a prerequisite to developing a long lasting roadway that does not require extensive future maintenance. This goal is achieved by verifying that design specifications are met through the use of quality assurance (QA) practices. The in-situ density is regarded as one of the most important controls used to ensure that a pavement being placed is of high quality because it is a good indicator of future performance. In-situ density is frequently assessed utilizing one or more of the following three methods: cores, nuclear density gauge measurements or non-nuclear density gauge measurements. Each of the above mentioned methods, however, have their distinct disadvantages. Cores, for example, are generally considered to be the most accurate means of measuring in-situ density, however, they are a time consuming and destructive test that introduces a defect into asphalt pavements. Because of the destructive nature associated with coring, contractors and agencies have alternatively used non-destructive nuclear and non-nuclear density gauges for quality control purposes. These instruments allow for a more rapid assessment of the in-situ density, allowing measurements to be taken even during the pavement's construction. The disadvantage of these gauges are that they provide density readings only at discrete locations of the asphalt pavement mat, while no consensus exists among pavement researchers on the proper correlation between the gauges and core density. In recent years, numerous alternative methods have been introduced for the assessment of in-situ density, both during asphalt pavement construction and afterwards. These methods include, amongst others, intelligent compaction, thermal imaging and ground penetrating radar (GPR). Among these methods, GPR has been defined as both a technically feasible and promising method for the nondestructive, rapid, and continuous evaluation of in-situ asphalt pavement density based on electromagnetic mixing (EM) theory, through the utilization of proper models. These models enable the prediction of asphalt mixture density dependent on its bulk dielectric constant as measured by the GPR, the dielectric properties of the asphalt mix materials, as well as other material information. The goal of the present study is to attempt to verify the prediction performance of various density models. To accomplish this goal GPR surveys were carried out in the field during asphalt pavement construction to evaluate the density results due to different compaction modes. The GPR data was analyzed to calculate the appropriate asphalt mix dielectric properties needed for the activation of the considered density prediction models. Predicted densities were compared with densities of the field cores extracted from the as-built asphalt pavement prior to trafficking. It was found that the predicted density values were significantly lower when compared to the ground truth data. A further investigation of the effect of temperature on GPR readings showed that GPR seems to overestimate the in-situ density. However, this approach could be used effectively to evaluate the performance of different compaction methods and set up the compaction pattern that is needed to achieve the desired asphalt pavement density.

  18. In Situ Microbial Community Control of the Stability of Bio-reduced Uranium

    International Nuclear Information System (INIS)

    In aerobic aquifers typical of many Department of Energy (DOE) legacy waste sites, uranium is present in the oxidized U(VI) form which is more soluble and thus more mobile. Field experiments at the Old Rifle UMTRA site have demonstrated that biostimulation by electron donor addition (acetate) promotes biological U(VI) reduction (2). However, U(VI) reduction is reversible and oxidative dissolution of precipitated U(IV) after the cessation of electron donor addition remains a critical issue for the application of biostimulation as a treatment technology. Despite the potential for oxidative dissolution, field experiments at the Old Rifle site have shown that rapid reoxidation of bio-reduced uranium does not occur and U(VI) concentrations can remain at approximately 20% of background levels for more than one year. The extent of post-amendment U(VI) removal and the maintenance of bioreduced uranium may result from many factors including U(VI) sorption to iron-containing mineral phases, generation of H2S or FeS0.9, or the preferential sorption of U(VI) by microbial cells or biopolymers, but the processes controlling the reduction and in situ reoxidation rates are not known. To investigate the role of microbial community composition in the maintenance of bioreduced uranium, in-well sediment incubators (ISIs) were developed allowing field deployment of amended and native sediments during on-going experiments at the site. Field deployment of the ISIs allows expedient interrogation of microbial community response to field environmental perturbations and varying geochemical conditions.

  19. A Technique for In-situ Measurement of Free Spectral Range and Transverse Mode Spacing of Optical Cavitie

    CERN Document Server

    Stochino, Alberto; Adhikari, Rana X

    2012-01-01

    Length and g-factor are fundamental parameters that characterize optical cavities. We developed a technique to measure these parameters in-situ by determining the frequency spacing between the resonances of fundamental and spatial modes of an optical cavity. Two laser beams are injected into the cavity, and their relative frequency is scanned by a phase-lock loop, while the cavity is locked to either laser. The measurement of the amplitude of their beat note in transmission reveals the resonances of the longitudinal and the transverse modes of the cavity and their spacing. This method proves particularly useful to characterize complex optical systems, including very long and/or coupled optical cavities, as in gravitational wave interferometers. This technique and the results of its application to the coupled cavities of a 40-meter-long gravitational wave interferometer prototype are here presented.

  20. Establishment of 60Co dose calibration curve using fluorescent in situ hybridization assay technique: Result of preliminary study

    International Nuclear Information System (INIS)

    This study aims at establishing an in-vitro 60Co dose calibration curve using Fluorescent In-Situ Hybridization assay technique for the Malaysian National Bio dosimetry Laboratory. Blood samples collected from a female healthy donor were irradiated with several doses of 60Co radiation. Following culturing of lymphocytes, microscopic slides are prepared, denatured and hybridized. The frequencies of translocation are estimated in the metaphases. A calibration curve was then generated using a regression technique. It shows a good fit to a linear-quadratic model. The results of this study might be useful in estimating absorbed dose for the individual exposed to ionizing radiation retrospectively. This information may be useful as a guide for medical treatment for the assessment of possible health consequences. (author)

  1. Real-time stability in power systems techniques for early detection of the risk of blackout

    CERN Document Server

    Savulescu, Savu

    2014-01-01

    This pioneering volume has been updated and enriched to reflect the state-of-the-art in blackout prediction and prevention. It documents and explains background and algorithmic aspects of the most successful steady-state, transient and voltage stability solutions available today in real-time. It also describes new, cutting-edge stability applications of synchrophasor technology, and captures industry acceptance of metrics and visualization tools that quantify and monitor the distance to instability. Expert contributors review a broad spectrum of additionally available techniques, such as traje

  2. Analysis to feature-based video stabilization/registration techniques within application of traffic data collection

    Science.gov (United States)

    Sadat, Mojtaba T.; Viti, Francesco

    2015-02-01

    Machine vision is rapidly gaining popularity in the field of Intelligent Transportation Systems. In particular, advantages are foreseen by the exploitation of Aerial Vehicles (AV) in delivering a superior view on traffic phenomena. However, vibration on AVs makes it difficult to extract moving objects on the ground. To partly overcome this issue, image stabilization/registration procedures are adopted to correct and stitch multiple frames taken of the same scene but from different positions, angles, or sensors. In this study, we examine the impact of multiple feature-based techniques for stabilization, and we show that SURF detector outperforms the others in terms of time efficiency and output similarity.

  3. Optical In-Situ Plasma Process Monitoring Technique for Detection of Abnormal Plasma Discharge

    Directory of Open Access Journals (Sweden)

    Sang Jeen Hong

    2013-04-01

    Full Text Available Advanced semiconductor manufacturing technology requires methods to maximize tool efficiency and improveproduct quality by reducing process variability. Real-time plasma process monitoring and diagnosis have becomecrucial for fault detection and classification (FDC and advanced process control (APC. Additional sensors mayincrease the accuracy of detection of process anomalies, and optical monitoring methods are non-invasive. In thispaper, we propose the use of a chromatic data acquisition system for real-time in-situ plasma process monitoringcalled the Plasma Eyes Chromatic System (PECS. The proposed system was initially tested in a six-inch researchtool, and it was then further evaluated for its potential to detect process anomalies in an eight-inch production toolfor etching blanket oxide films. Chromatic representation of the PECS output shows a clear correlation with smallchanges in process parameters, such as RF power, pressure, and gas flow. We also present how the PECS may beadapted as an in-situ plasma arc detector. The proposed system can provide useful indications of a faulty process in atimely and non-invasive manner for successful run-to-run (R2R control and FDC.

  4. Cu-Ti Formation in Nb-Ti/Cu Superconducting Strand Monitored by in situ Techniques

    CERN Document Server

    Pong, I; Pong, Ian; Gerardin, Alexandre; Scheuerlein, Christian; Bottura, Luca

    2010-01-01

    In order to investigate the high temperature exposure effect on Nb-Ti/Cu superconducting strands, as might be encountered in joining by soldering and in cabling annealing, X-ray diffraction and resistometry measurements were performed in situ during heat treatment, and complemented by conventional metallography, mechanical tests and superconducting properties measurements. Changes of the Nb-Ti nanostructure at temperatures above 300 degrees C are manifested in the degradation of critical current in an applied external magnetic field, although degradation at self field was insignificant up to 400 degrees C for several minutes. Above 500 degrees C, the formation of various Cu-Ti intermetallic compounds, due to Ti diffusion from Nb-Ti into Cu, is detected by in situ XRD albeit not resolvable by SEM-EDS. There is a ductile to brittle transition near 600 degrees C, and liquid formation is observed below 900 degrees C. The formation of Cu-Ti causes a delayed reduction of the residual resistivity ratio (RRR) and adv...

  5. Effects and thermal stability of hydrogen microwave plasma treatment on tetrahedral amorphous carbon films by in situ ultraviolet photoelectron spectroscopy

    International Nuclear Information System (INIS)

    This paper reports a comprehensive experimental study on the effects of hydrogen microwave plasma treatment on nonhydrogenated high sp3 content tetrahedral amorphous carbon (ta-C) film. In this study, a surface C-H dipole layer was first observed by high resolution electron energy loss spectroscopy, showing the presence of C-H bonding states. This resulted in the enhancement of electron field emission of the plasma treated films by largely lowering the turn-on field. Thermal stability tests using in situ ultraviolet photoelectron spectroscopy confirm that the C-H dipole layer not only reduces the work function of the films, it is extremely stable in both ambient and vacuum conditions and can sustain up to 600 deg. C annealing in vacuum. Atomic force microscopy studies also show minimal modifications to the surface morphology, leading to the conclusion that the C-H dipole layer is responsible for lowering the work function. This has improved the electron emission properties which can lead to potential applications such as electron emission displays.

  6. Kinetic stabilization of Fe film on GaAs(100): An in situ x-ray reflectivity Study

    CERN Document Server

    Kim, T C; Kim, Y; Noh, D Y; OH, S J; Kim, J S

    2006-01-01

    We study the growth of the Fe films on GaAs(100) at a low temperature, 140 K, by $in$-$situ$ UHV x-ray reflectivity using synchrotron radiation. We find rough surface with the growth exponent, $\\beta_S$ = 0.51$\\pm$0.04. This indicates that the growth of the Fe film proceeds via the restrictive relaxation due to insufficient thermal diffusion of the adatoms. The XRR curves are nicely fit by a model with a uniform Fe film, implying that the surface segregation and interface alloying of both Ga and As are negligible. When the Fe film is annealed to 300 K, however, the corresponding XRR can be fit only after including an additional layer of 9 A thickness between the Fe film and the substrate, indicating the formation of ultrathin alloy near the interface. The confinement of the alloy near the interface derives from the fact that the diffusion of Ga and As from the substrate should proceed via the inefficient bulk diffusion, and hence the overlying Fe film is kinetically stabilized.

  7. A New in Situ Synchrotron X-ray Diffraction Technique to Study the Chemical Delithiation of LiFePO4

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.Y.; Chen, H.-Y.; Yu, X.; Wu, L.; Nam, K.-W.; Bai, J.; Li, H.; Huang, X.; Yang, X.-Q.

    2011-07-07

    We report a new synchrotron based in situ X-ray diffraction (XRD) technique to study the chemical delithiation of LiFePO{sub 4}. This technique provides a new powerful tool to study chemical reactions with excellent time-resolving power for dynamic studies.

  8. A New in Situ Synchrotron X-ray Diffraction Technique to Study the Chemical Delithiation of LiFePO4

    Energy Technology Data Exchange (ETDEWEB)

    X Wang; H Chen; X Yu; L Wu; K Nam; J Bai; H Li; X Huang; X Yang

    2011-12-31

    We report a new synchrotron based in situ X-ray diffraction (XRD) technique to study the chemical delithiation of LiFePO{sub 4}. This technique provides a new powerful tool to study chemical reactions with excellent time-resolving power for dynamic studies.

  9. ‘Expansion in-situ’ concept as a new technique for expanding skin and soft tissue

    OpenAIRE

    Fang, Lin; Zhou, Chuande; Yang, Mingyong

    2013-01-01

    Techniques for expanding skin and soft tissue are widely used to repair damaged areas since they facilitate the provision of new, additional skin tissue with similar quality, texture and color to that surrounding the defective area. Conventional expansion techniques involve placing expanders under the normal skin adjacent to a lesion. However, these techniques may involve additional incisions, complications with blood supply and ‘dog-ear’ deformities and may result in a low utilization ra...

  10. Ambient in-situ immersion freezing measurements - findings from the ZAMBIS 2014 field campaign for three ice nucleation techniques

    Science.gov (United States)

    Kohn, Monika; Atkinson, James D.; Lohmann, Ulrike; Kanji, Zamin A.

    2015-04-01

    To estimate the influence of clouds on the Earth's radiation budget, it is crucial to understand cloud formation processes in the atmosphere. A key process, which significantly affects cloud microphysical properties and the initiation of precipitation thus contributing to the hydrological cycle, is the prevailing type of ice nucleation mechanism. In mixed-phase clouds immersion freezing is the dominant ice crystal forming mechanism, whereby ice nucleating particles (INP) first act as cloud condensation nuclei (CCN) and are activated to cloud droplets followed by freezing upon supercooling. There are a number of experimental methods and techniques to investigate the ice nucleating ability in the immersion mode, however most techniques are offline for field sampling or only suitable for laboratory measurements. In-situ atmospheric studies are needed to understand the ice formation processes of 'real world' particles. Laboratory experiments simulate conditions of atmospheric processes like ageing or coating but are still idealized. Our method is able to measure ambient in-situ immersion freezing on single immersed aerosol particles. The instrumental setup consists of the recently developed portable immersion mode cooling chamber (PIMCA) as a vertical extension to the portable ice nucleation chamber (PINC, [1]), where the frozen fraction of activated aerosol particles are detected by the ice optical depolarization detector (IODE, [2]). Two additional immersion freezing techniques based on a droplet freezing array [3,4] are used to sample ambient aerosol particles either in a suspension (fraction larger ~0.6 ?m) or on PM10-filters to compare different ice nucleation techniques. Here, we present ambient in-situ measurements at an urban forest site in Zurich, Switzerland held during the Zurich ambient immersion freezing study (ZAMBIS) in spring 2014. We investigated the ice nucleating ability of natural atmospheric aerosol with the PIMCA/PINC immersion freezing setup as well as a droplet freezing method on aerosol particles either collected in a suspension or on PM10-filters to obtain atmospheric IN concentrations based on the measured ambient aerosol. Investigation of physical properties (number and size distribution) and chemical composition as well as the meteorological conditions provide supplementary information that help to understand the nature of particles and air masses that contribute to immersion freezing. Acknowledgements We thank Hannes Wydler and Hansjörg Frei from ETH Zurich for their technical support. Furthermore, the authors want thank Franz Conen from the University of Basel for sharing equipment and training in the drop freezing experiment. References [1] Chou et al. (2011), Atmos. Chem. Phys., 11, 4725-4738. [2] Nicolet et al. (2010), Atmos. Chem. Phys., 10, 313-325. [3] Conen et al. (2012), Atmos. Meas. Tech., 5, 321-327. [4] Stopelli et al. (2014), Atmos. Meas. Tech., 7, 129-134.

  11. IN-SITU CHEMICAL STABILIZATION OF METALS AND RADIONUCLIDES THROUGH ENHANCED ANAEROBIC REDUCTIVE PRECIPITATION

    Energy Technology Data Exchange (ETDEWEB)

    Christopher C. Lutes; Angela Frizzell, PG; Todd A. Thornton; James M. Harrington

    2003-08-01

    The objective of this NETL sponsored bench-scale study was to demonstrate the efficacy of enhanced anaerobic reductive precipitation (EARP) technology for precipitating uranium using samples from contaminated groundwater at the Fernald Closure Project (FCP) in Cincinnati, Ohio. EARP enhances the natural biological reactions in the groundwater through addition of food grade substrates (typically molasses) to drive the oxidative-reductive potential of the groundwater to a lower, more reduced state, thereby precipitating uranium from solution. In order for this in-situ technology to be successful in the long term, the precipitated uranium must not be re-dissolved at an unacceptable rate once groundwater geochemical conditions return to their pretreatment, aerobic state. The approach for this study is based on the premise that redissolution of precipitated uranium will be slowed by several mechanisms including the presence of iron sulfide precipitates and coatings, and sorption onto fresh iron oxides. A bench-scale study of the technology was performed using columns packed with site soil and subjected to a continuous flow of uranium-contaminated site groundwater (476 {micro}g/L). The ''treated'' column received a steady stream of dilute food grade molasses injected into the contaminated influent. Upon attainment of a consistently reducing environment and demonstrated removal of uranium, an iron sulfate amendment was added along with the molasses in the influent solution. After a month long period of iron addition, the treatments were halted, and uncontaminated, aerobic, unamended water was introduced to the treated column to assess rebound of uranium concentrations. In the first two months of treatment, the uranium concentration in the treated column decreased to the clean-up level (30 {micro}g/L) or below, and remained there for the remainder of the treatment period. A brief period of resolubilization of uranium was observed as the treated column returned to aerobic conditions, but the concentration later returned to below the clean-up level. Speciation analysis was conducted on soil collected from the treated column after rebound testing. The experimental results show that: (a) The mass of uranium resolubilized in more than four months of column testing was much lower than the amount precipitated. (b) The majority of the uranium was precipitated in the first few inches of the treated column. The majority of the uranium precipitated was associated with iron oxides or in other immobile/sequestered phases. It is important to contrast this result with the results reported by Bryan (2003) who shows that most of the uranium associated with contaminated aquifer solids at Fernald under the existing natural attenuation/pump and treat with reinjection conditions is carbonate bound. Carbonate bound forms are traditionally seen as fairly mobile, but may not be under a calcite/dolomite saturated condition. Fernald is currently conducting further studies to investigate the mobility of the carbonate bound forms. (c) Though reoxidation concentrations from the bench-scale column exceeded 30 {micro}g/L for a time, they later returned to below this value. Effluent concentrations from the treated column are expected to over predict full-scale concentrations for reasons discussed in depth in the text. Finally, these results must be viewed in light of the site's ongoing pump-and-treat with reinjection system. There is reason to believe that although the pump-and-treat technology is currently effectively controlling the uranium plume and reducing the groundwater concentration, it may not be able to reach the treatment standard of 30 {micro}g/L within an economical operating lifetime and then maintain that concentration without rebound. This study suggests that Enhanced Anaerobic Reductive Precipitation can change the speciation and thus reduce the mobility of uranium at the site and expedite closure.

  12. Recent trends in non-invasive in situ techniques to monitor bacterial colonies in solid (model) food

    Science.gov (United States)

    Lobete, María M.; Fernandez, Estefania Noriega; Van Impe, Jan F. M.

    2015-01-01

    Planktonic cells typically found in liquid systems, are routinely used for building predictive models or assessing the efficacy of food preserving technologies. However, freely suspended cells often show different susceptibility to environmental hurdles than colony cells in solid matrices. Limited oxygen, water and nutrient availability, metabolite accumulation and physical constraints due to cell immobilization in the matrix, are main factors affecting cell growth. Moreover, intra- and inter-colony interactions, as a consequence of the initial microbial load in solid systems, may affect microbial physiology. Predictive food microbiology approaches are moving toward a more realistic resemblance to food products, performing studies in structured solid systems instead of liquids. Since structured systems promote microbial cells to become immobilized and grow as colonies, it is essential to study the colony behavior, not only for food safety assurance systems, but also for understanding cell physiology and optimizing food production processes in solid matrices. Traditionally, microbial dynamics in solid systems have been assessed with a macroscopic approach by applying invasive analytical techniques; for instance, viable plate counting, which yield information about overall population. In the last years, this approach is being substituted by more mechanistically inspired ones at mesoscopic (colony) and microscopic (cell) levels. Therefore, non-invasive and in situ monitoring is mandatory for a deeper insight into bacterial colony dynamics. Several methodologies that enable high-throughput data collection have been developed, such as microscopy-based techniques coupled with image analysis and OD-based measurements in microplate readers. This research paper provides an overview of non-invasive in situ techniques to monitor bacterial colonies in solid (model) food and emphasizes their advantages and inconveniences in terms of accuracy, performance and output information. PMID:25798133

  13. Robust Coordinated Design of PSS and TCSC using PSO Technique for Power System Stability Enhancement

    Directory of Open Access Journals (Sweden)

    S. Panda

    2007-06-01

    Full Text Available Power system stability improvement by coordinated design of a Power System Stabilizer (PSS and a Thyristor Controlled Series Compensator (TCSC controller is addressed in this paper. Particle Swarm Optimization (PSO technique is employed for optimization of the parameterconstrained nonlinear optimization problem implemented in a simulation environment. The proposed controllers are tested on a weakly connected power system. The non-linear simulation results are presented for wide range of loading conditions with various fault disturbances and fault clearing sequences as well as for various small disturbances. The eigenvalue analysis and simulation results show the effectiveness and robustness of proposed controllers to improve the stability performance of power system by efficient damping of low frequency oscillations under various disturbances.

  14. Comparación de las técnicas in situ, in vitro y enzimática (celulasa) para estimar la digestibilidad de forrajes en ovinos / Comparison of the in situ, in vitro and Enzimatic (Cellulase) Techniques for Digestibility Estimation of Forages in Sheep

    Scientific Electronic Library Online (English)

    Giovanna, Torres G.; Teresa, Arbaiza F.; Fernando, Carcelén C.; Orlando, Lucas A..

    Full Text Available Se comparó los resultados de las técnicas in vitro, in situ y enzimática (celulasa) para estimar la digestibilidad de forrajes de diferente calidad nutritiva en ovinos. Se colectó muestras de forraje de tres calidades: alta (rye grass de 2-4 semanas), media (rye grass de 8 semanas y heno de alfalfa) [...] y baja (paja de avena). Las muestras fueron secadas, molidas y pasaron por tamiz de 1 mm para la técnica in vitro y celulasa y 3 mm para la técnica in situ. Se determinó la digestibilidad in vitro de la materia seca (DIVMS), digestibilidad in situ de la materia seca (DISMS) y digestibilidad a la celulasa de la materia seca (DCMS). Se emplearon tres ovinos con fístula ruminal y alimentados con maíz forrajero y heno de alfalfa. Se usó un diseño experimental con arreglo factorial de 4 x 3 (4 calidades de forraje y 3 técnicas). La DISMS fue superior (p Abstract in english The objective of the study was to compare the efficiency of the in situ, in vitro and enzymatic (cellulose) techniques in estimating the digestibility of forage with different nutritional quality in sheep. Samples of three qualities of forage were collected: high (rye grass of 2-4 weeks), medium (ry [...] e grass of 8 weeks and alfalfa hay), and low (oat straw). The samples were dried, grounded and passed through 1 mm sieve for the in vitro and cellulose technique and 3 mm sieve for the in situ technique. The in vitro digestibility of dry matter (IVDDM), in situ digestibility of dry matter (ISDDM), and cellulose digestibility of dry matter (CDDM) were determined. Three adult rams with ruminal fistula and fed with a diet based on alfalfa hay and corn stalk. A complete randomized 4 x 3 experimental design (4 quality forages and 3 techniques) was used. The ISDDM was higher (p

  15. In situ non-invasive investigation on the painting techniques of early Meissen Stoneware

    Science.gov (United States)

    Miliani, Costanza; Doherty, Brenda; Daveri, Alessia; Loesch, Anette; Ulbricht, Heike; Brunetti, Brunetto G.; Sgamellotti, Antonio

    2009-08-01

    In situ, non-invasive investigations by means of portable X-ray fluorescence and fibre optic reflectance mid-infrared (mid-FTIR) spectroscopy of painted Böttger Stoneware objects have been carried out through the MOLAB transnational access to the Porcelain Collection of the Staatliche Kunstsammlungen in Dresden. It has been possible to gather information regarding the composition of the black glaze by applying a principal component analysis to the elemental analysis to distinguish between the variations of lead, iron and manganese compositions of each glaze. It has been furthermore feasible to combine molecular spectroscopy for characterization of the constituent painting materials, namely lead white as cerusite and hydrocerusite, the use of cinnabar, azurite and Prussian blue leading to a better knowledge of the state of conservation and utility of certain pigments that may give rise to chronology of the decorative artwork. The identification of oxalates namely whedellite and moolooite are assigned as degradation products relative to the decorative areas.

  16. Ultrasonic techniques for the in situ characterisation of 'legacy' Waste sludges and dispersions - 59111

    International Nuclear Information System (INIS)

    Research being undertaken at the University of Leeds, as part of the DIAMOND university consortium, is exploring the effectiveness of various ultrasonic technologies as in situ probes to characterize and monitor nuclear waste slurries, such as the 'Legacy' Magnesium hydroxide sludges found in Sellafield, U.K. Through use of a commercial Acoustic Backscatter Sensor (ABS) with 1 - 5 MHz transducers, various properties of free-settling oxide simulant sludges were determined. Work was focused upon characterizing essentially 'static' sludges (to give prospective use as tools for the wastes in current deposits); although, the sensors also have potential as dispersion monitors during any future processing and storage of the Legacy wastes, as well as many other storage, clarifier or thickener systems across a wide range of industrial processing operations. ABS data of mixed glass powder dispersions was analysed and compared to scattering theory, to understand the correlations between acoustic attenuation and particulate concentration. The ABS was also calibrated to measure changes in average particulate concentration within a settling suspension over time, and showed the depth-wise segregation of the dispersion through the settling column at different particular time intervals. It was found that observed hindered settling also led to an increase in particulate concentration over the sludge zone and significant segregation occurred at moderate time intervals, due to the broad moderate time intervals, due to the broad size distribution of the aggregates measured. It is hoped in future that these sensors may be able to be fitted to robotic handlers that have been installed onsite (and previously used for sampling), allowing fully automatic in situ sludge analysis. (authors)

  17. Development of laser-based techniques for in situ characterization of the first wall in ITER and future fusion devices

    Science.gov (United States)

    Philipps, V.; Malaquias, A.; Hakola, A.; Karhunen, J.; Maddaluno, G.; Almaviva, S.; Caneve, L.; Colao, F.; Fortuna, E.; Gasior, P.; Kubkowska, M.; Czarnecka, A.; Laan, M.; Lissovski, A.; Paris, P.; van der Meiden, H. J.; Petersson, P.; Rubel, M.; Huber, A.; Zlobinski, M.; Schweer, B.; Gierse, N.; Xiao, Q.; Sergienko, G.

    2013-09-01

    Analysis and understanding of wall erosion, material transport and fuel retention are among the most important tasks for ITER and future devices, since these questions determine largely the lifetime and availability of the fusion reactor. These data are also of extreme value to improve the understanding and validate the models of the in vessel build-up of the T inventory in ITER and future D-T devices. So far, research in these areas is largely supported by post-mortem analysis of wall tiles. However, access to samples will be very much restricted in the next-generation devices (such as ITER, JT-60SA, W7-X, etc) with actively cooled plasma-facing components (PFC) and increasing duty cycle. This has motivated the development of methods to measure the deposition of material and retention of plasma fuel on the walls of fusion devices in situ, without removal of PFC samples. For this purpose, laser-based methods are the most promising candidates. Their feasibility has been assessed in a cooperative undertaking in various European associations under EFDA coordination. Different laser techniques have been explored both under laboratory and tokamak conditions with the emphasis to develop a conceptual design for a laser-based wall diagnostic which is integrated into an ITER port plug, aiming to characterize in situ relevant parts of the inner wall, the upper region of the inner divertor, part of the dome and the upper X-point region.

  18. Stable Sensor Network (SSN): A Dynamic Clustering Technique for Maximizing Stability in Wireless Sensor Networks

    OpenAIRE

    Humayun Kabir; Chowdhury Sayeed Hyder; Alim Al Islam, A. B. M.; Mahmuda Naznin

    2010-01-01

    Stability is one of the major concerns in advancement of Wireless Sensor Networks (WSN). A number of applications of WSN require guaranteed sensing, coverage and connectivity throughout its operational period. Death of the first node might cause instability in the network. Therefore, all of the sensor nodes in the network must be alive to achieve the goal during that period. One of the major obstacles to ensure these phenomena is unbalanced energy consumption rate. Different techniques have a...

  19. Observation of localized heating phenomena during microwave heating of mixed powders using in situ x-ray diffraction technique

    Science.gov (United States)

    Sabelström, N.; Hayashi, M.; Watanabe, T.; Nagata, K.

    2014-10-01

    In materials processing research using microwave heating, there have been several observations of various phenomena occurring known as microwave effects. One significant example of such a phenomenon is increased reaction kinetics. It is believed that there is a possibility that this might be caused by localized heating, were some reactants would attain a higher than apparent temperature. To examine whether such thermal gradients are indeed possible, mixed powders of two microwave non-absorbers, alumina and magnesia, were mixed with graphite, a known absorber, and heated in a microwave furnace. During microwave irradiation, the local temperatures of the respective sample constituents were measured using an in situ x-ray diffraction technique. In the case of the alumina and graphite sample, a temperature difference of around 100 °C could be observed.

  20. Flow characterization of electroconvective micromixer with a nanoporous polymer membrane in-situ fabricated using a laser polymerization technique.

    Science.gov (United States)

    Hwang, Sangbeom; Song, Simon

    2015-05-01

    Electroconvection is known to cause strong convective mixing in a microchannel near a nanoporous membrane or a nanochannel in contact with an electrolyte solution due to the external electric field. This study addresses micromixer behavior subject to electroconvection occurring near a nanoporous membrane in-situ fabricated by a laser polymerization technique on a microfluidic chip. We found that the micromixer behavior can be categorized into three regimes. Briefly, the weak electroconvection regime is characterized by weak mixing performance at a low applied voltage and KCl concentration, whereas the strong electroconvection regime has a high mixing performance when the applied voltage and KCl concentration are moderately high. Finally, the incomplete electroconvection regime has an incomplete electric double-layer overlap in the nanopores of the membrane when the electrolyte concentration is very high. The mixing index reached 0.92 in the strong electroconvection regime. The detailed fabrication methods for the micromixer and characterization results are discussed in this paper. PMID:26064195

  1. Observation of localized heating phenomena during microwave heating of mixed powders using in situ x-ray diffraction technique

    International Nuclear Information System (INIS)

    In materials processing research using microwave heating, there have been several observations of various phenomena occurring known as microwave effects. One significant example of such a phenomenon is increased reaction kinetics. It is believed that there is a possibility that this might be caused by localized heating, were some reactants would attain a higher than apparent temperature. To examine whether such thermal gradients are indeed possible, mixed powders of two microwave non-absorbers, alumina and magnesia, were mixed with graphite, a known absorber, and heated in a microwave furnace. During microwave irradiation, the local temperatures of the respective sample constituents were measured using an in situ x-ray diffraction technique. In the case of the alumina and graphite sample, a temperature difference of around 100?°C could be observed.

  2. Observation of localized heating phenomena during microwave heating of mixed powders using in situ x-ray diffraction technique

    Energy Technology Data Exchange (ETDEWEB)

    Sabelström, N., E-mail: sabelstrom.n.aa@m.titech.ac.jp; Hayashi, M. [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, Tokyo 152-8552 (Japan); Watanabe, T. [Department of Chemistry and Materials Science, Tokyo Institute of Technology, Tokyo 152-8552 (Japan); Nagata, K. [Department of Conservation Science, Tokyo University of the Arts, 12-8 Ueno Park, Taito-ku, Tokyo (Japan)

    2014-10-28

    In materials processing research using microwave heating, there have been several observations of various phenomena occurring known as microwave effects. One significant example of such a phenomenon is increased reaction kinetics. It is believed that there is a possibility that this might be caused by localized heating, were some reactants would attain a higher than apparent temperature. To examine whether such thermal gradients are indeed possible, mixed powders of two microwave non-absorbers, alumina and magnesia, were mixed with graphite, a known absorber, and heated in a microwave furnace. During microwave irradiation, the local temperatures of the respective sample constituents were measured using an in situ x-ray diffraction technique. In the case of the alumina and graphite sample, a temperature difference of around 100?°C could be observed.

  3. Evaluation of three new laser spectrometer techniques for in-situ carbon monoxide measurements

    Directory of Open Access Journals (Sweden)

    C. Zellweger

    2012-07-01

    Full Text Available Long-term time series of the atmospheric composition are essential for environmental research and thus require compatible, multi-decadal monitoring activities. However, the current data quality objectives of the World Meteorological Organization (WMO for carbon monoxide (CO in the atmosphere are very challenging to meet with the measurement techniques that have been used until recently. During the past few years, new spectroscopic techniques came on the market with promising properties for trace gas analytics. The current study compares three instruments that are recently commercially available (since 2011 with the up to now best available technique (vacuum UV fluorescence and provides a link to previous comparison studies. The instruments were investigated for their performance regarding repeatability, reproducibility, drift, temperature dependence, water vapour interference and linearity. Finally, all instruments were examined during a short measurement campaign to assess their applicability for long-term field measurements. It could be shown that the new techniques provide a considerably better performance compared to previous techniques, although some issues such as temperature influence and cross sensitivities need further attention.

  4. A new tracer technique for in situ experimental study of bioturbation processes

    International Nuclear Information System (INIS)

    An experimental method has been developed to study material and radioactivity fluxes at the sediment-water interface and in the sedimentary column. This method has been applied in the Gulf of Fos, an area that is affected by deposits from the river Rhone, and where biodeposition products, resulting from the presence of intensive mussel cultures, can induce a concentration of trace elements at the sediment-water interface. Sediment surface materials were labelled with a mixture of radionuclides (Cerium-144, Cobalt-60 and Cesium-137), in experimental cores filled either with sediment containing in situ fauna or with defaunated sediment. The coupling of this mixture with inert colored sediment particles enabled us to measure radionuclide flux in both solute fraction and solid fraction. At the sediment-water interface, the tracer balance indicates that migrations into deeper sediment are estimated to be until 25 times greater in presence of macrofauna, depending on the tracer examined. Bioturbation may equally enhance exportation to the water column, to a factor ranging from 1.5 to 2.0. During a period of 14 days, in presence of macrofauna, we observed a migration of radionuclides to a maximum depth of 11 cm. A similar distribution pattern of luminophores at the same sediment depths indicates the preponderance of particle reworking in migration. (Author)

  5. Evaluation of in situ mechanical properties of composites by using nanoindentation techniques

    International Nuclear Information System (INIS)

    The in situ mechanical properties of the fibers, matrices and interfaces in an Al2O3 fiber-reinforced ?-21S Ti alloy have been evaluated by using two nanoscale indentation tests. The Al2O3 fibers were coated with a refractory metal and Y2O3 duplex coating which served as a diffusion barrier during the HIPing used to produce the metal matrix composites. The hardness of the fibers, interfaces and matrix were obtained by performing a series of indentations across the fiber/matrix interface. The hardness decreases from the Al2O3 fiber to the Ti matrix. Additionally, by doing fiber pushout tests, the interfacial shear strength, interfacial frictional stress and mode 2 interfacial fracture energy were obtained. Scanning electron microscopy and X-ray mapping were used for microstructural and chemical analysis. The mechanical properties of the interfaces were related to their chemical composition. The interfacial fracture was found to occur at the interface between the refractory metal and the Y2O3. The mode 2 interfacial fracture energy in this system is more than two orders of magnitude lower than the interfacial fracture energy of Ti/Al2O3 without the diffusion barrier

  6. A novel fluidized bed respirometric technique for determination of in situ biofilm kinetics.

    Science.gov (United States)

    Chowdhury, Nabin; Nakhla, George; Zhu, Jesse

    2012-01-01

    A respirometric approach has been developed to determine heterotrophic biofilm kinetics using fluidized bioparticles--particles with attached biomass. Lava rock particles of 600 microm were used as a biomass carrier medium. The modified respirometer successfully estimates in situ biofilm kinetics of the bioparticles collected from a pilot-scale liquid-solid circulating fluidized bed (LSCFB) bioreactor. The observed maximum specific growth rates (micro(max)) of 3.69 +/- 0.44 d(-1) and biomass yields (Y(H)) of 0.36 +/- 0.03 g COD/g COD in the fluidized bed respirometers were significantly different from the micro(max) of 5.57-5.72 d(-1) and Y(H) of 0.54-0.59 g COD/g COD observed in the conventional respirometric tests for bioparticles and detached biomass. The higher Monod half-saturation coefficient (K(S)) of 186-219mg COD/L observed in the fluidized bed respirometers relative to the 49-58 mg COD/L in the conventional respirometers reveals the presence of mass transfer resistance in the LSCFB despite fluidization. Significantly reduced yields in the fluidized bed respirometers and the estimated maintenance coefficient of 1.16 d(-1) for the particulate biofilm in the LSCFB clearly emphasize that a substantial amount of substrate was utilized for cell maintenance at the low food to microorganism (S/X) ratio of 0.5 g COD/g VSS. PMID:22629617

  7. Nuclear borehole logging techniques developed by CSIRO - Exploration and Mining for in situ evaluation of coal and mineral deposits

    International Nuclear Information System (INIS)

    CSIRO - Exploration and Mining Division has developed a spectrometric nuclear techniques for in situ evaluation of coal and mineral deposits. Whilst the use of this technology is seen mainly in coal mining, it is becoming increasingly apparent in metalliferous mining. The logging tools developed by CSIRO are using the gamma-gamma, prompt neutron activation and spectrometric natural gamma techniques. The technology is used both in exploration and mine production for quality control. Nuclear borehole logging is complementary to the laboratory analysis of core samples retrieved from boreholes. Although it can not provide the same detailed information as the analysis of the core, the volume of rock sampled by nuclear borehole logging is much larger than the core samples and the results are provided almost instantaneously. Nuclear logging is particularly useful for mineral deposits where the core can not be fully recovered or in situations when not all the information provided by the analysis of the core is needed. Important savings can be made if the information required is acquired by logging open holes instead of drilling more expensive cored holes. The paper reviews various techniques developed by CSIRO - Exploration and Mining for both the coal and metalliferous mining industry. Emphasis is given to current research for developing logging tools equipped with ultra - low intensity gamma-ray sources (below 3.7 MBq activity). The tools are developed for both borehole logging and face analysis

  8. In-situ stabilization of radioactively contaminated low-level solid wastes buried in shallow trenches: an assessment

    International Nuclear Information System (INIS)

    The potential effectiveness of materials for in-situ encapsulation of low-level, radioactively contaminated solid waste buried in shallow trenches is enumerated. Cement, clay materials, and miscellaneous sorbents, aqueous and nonaqueous gelling fluids and their combinations are available to solidify contaminated free water in trenches, to fill open voids, and to minimize radionuclide mobility. The success of the grouting technique will depend on the availability of reliable geohydrologic data and laboratory development of a mix with enhanced sorption capacity for dominant radionuclides present in the trenches. A cement-bentonite-based grout mix with low consistency for pumping, several hours controlled rate of hardening, negligible bleeding, and more than 170 kPa (25 psi) compressive strength are a few of the suggested parameters in laboratory mix development. Cost estimates of a cement-bentonite-based grout mix indicate that effective and durable encapsulation can be accomplished at a reasonable cost (about $113 per cubic meter). However, extensive implementation of the method suggests the need for a field demonstration of the method. 53 references

  9. Semi-destructive techniques for in-situ evaluation of historic wood structures.

    Czech Academy of Sciences Publication Activity Database

    Kasal, Bohumil; Anthony, R.W.

    Praha : Ústav teoretické a aplikované mechaniky AV ?R, 2007. s. 42-49. ISBN 978-80-86246-36-9 R&D Projects: GA MŠk(CZ) ME 887 Institutional research plan: CEZ:AV0Z20710524 Keywords : semi- destructive techniques * historic wood structures * material properties Subject RIV: AL - Art, Architecture, Cultural Heritage

  10. Coating stresses in thermal barrier coatings by an in-situ curvature monitoring technique

    International Nuclear Information System (INIS)

    In this paper, coating stresses in thermal barrier coating (TBC) changing with cyclic heating - cooling are measured with a curvature measurement device developed in this study. The coating system chosen in this study is a dual-layered structure, and it consists of a partially stabilized zirconia (PSZ) as the ceramic coating layer and CoNiCrAlY as the metal-bond coating layer. The specimen used here is a strip-plate shape with thin thickness (600?m) extracted chemically from carbon steel coated by a thermal spraying process. A cyclic heating-cooling test and a cyclic heating-cooling test with a dwelling time at the maximum temperature are conducted for the strip-plate specimen. Deflection and coating stresses are measured continuously under these cyclic tests, and thermal deformation mechanisms generating the deflection and coating stresses are discussed based on primitive knowledge using an elementary beam theory. (author)

  11. A bipolar LED drive technique for high performance, stability and power in the nanosecond time scale

    Science.gov (United States)

    Ronchi, E.; Andersson Sundén, E.; Conroy, S.; Ericsson, G.; Gatu Johnson, M.; Kallne, J.; Hellesen, C.; Hjalmarsson, A.; Sjöstrand, H.; Weiszflog, M.; Puccio, W.; Åhlén, L.; JET-EFDA Contributors

    2009-02-01

    Pulsed light sources are often used to monitor the stability of light detectors such as photomultiplier tubes. Light emitting diodes (LEDs) are suitable for this due to their high specific light yield. While pulsed operation in the region of ?s is generally accessible with most LEDs and drivers, the ns time scale often represents a technical challenge. This paper describes a technique of bipolar LED drive that can produce light pulses of a few ns at high stability, reliability and power. The driver also offers control over the properties of the light pulse produced such as shape, intensity and repetition rate. This approach has been studied in 2003 and implemented in 2004 for two fusion neutron spectrometers at the Joint European Torus (JET) namely the Magnetic Proton Recoil upgrade (MPRu) and the Time Of Flight Optimized for Rate (TOFOR). A driver has been manufactured and connected to the scintillation detectors of each spectrometer through an optical fiber distribution network. Both MPRu and TOFOR have been successfully relying on this system for calibration and performance monitoring for several years, confirming the long-term stability and reliability of this technique.

  12. Sinus elevation by in situ utilization of bone scrapers: technique and results

    Scientific Electronic Library Online (English)

    Pedro, Martos Díaz; Luis, Naval Gías; Jesús, Sastre Pérez; Raúl, González García; Fernando, Bances del Castillo; María, Mancha de la Plata; Pablo, Galindo Moreno; Mario, Muñoz Guerra.

    2007-11-01

    Full Text Available Objectives: The objective was to present a novel technique for antrostomy performed before sinus elevation in atrophic maxilla for subsequent implant placement. Material and methods: The study included 10 sinus elevations performed by the proposed technique in nine consecutive patients presenting wi [...] th inadequate posterior maxillary height. The technique is described, calculating the antrostomy surface area, volume of bone tissue obtained and final height attained in each case. A total of 16 implants were placed. Results: All ten elevations were accomplished. Mean antrostomy surface area was 0.55 mm², mean bone volume obtained was 0.56 cm³ and mean height attained was 11.7 mm from a baseline mean height of 5.6 mm. Out of the 16 implants, 14 were inserted immediately after the elevation and 2 were inserted in a second step, after ossification; 93.7% of the implants were osseointegrated at 6 months after prosthesis placement. Conclusion: The use of bone scrapers to create antrostomy for sinus elevation is a simple and very safe procedure. It provides a variable amount of particulate bone graft that is easily handled and highly useful for packing the cavity that will elevate the sinus membrane.

  13. In situ sorbtion techniques for radiocaesium. Rapid group separation and measurement of actinides

    International Nuclear Information System (INIS)

    Full text: a) A technique for impregnation of filters with copperferrocyanide has been developed. The sorbtion of radiocaesium has been tested on different types of liquids containing radiocaesium; urine (1-2 l), lake, river and sea water (100-2000 l) and dialysis liquid (120 l). The efficiency and analytical results were investigated and compared with results using ammonium molybdophosphate for sorbtion of caesium. Results are in good agreement with volumes not exceeding 500 I using two consecutive filters. Assessment of radiocaesium in large groups of people can be done rapidly by sorbtion from urine. Persons with malfunctioning kidneys and undergoing regular dialysis do not constitute a critical group. Dialysis is an effective method for cleaning the blood from radiocaesium. b) Actinides can be grouped separately from the bulk of solids using anion exchange from polar solvent-mineral acid media. This method is known since long. In combination with new techniques for source preparation using fluoride precipitation and new measurement techniques, mass spectrometry, laser excitation or gridded ion chambers (if sources have to be large) offers a possibility to shorten the analytical method. 2) Proposed Work for the Next Year: Decontamination of iodine (131I) from the body using dialysis will be investigated. Also other radiologically important radionuclides, 210Po and 226Ra will be investigated with this emphasis. Source preparation by fluoride precipitation and large area sources measured with gridded ionization chamber will be executed. (author)

  14. Comparison of continuous in-situ CO2 observations at Jungfraujoch using two different measurement techniques

    Science.gov (United States)

    Schibig, M. F.; Steinbacher, M.; Buchmann, B.; van der Laan-Luijkx, I. T.; van der Laan, S.; Ranjan, S.; Leuenberger, M. C.

    2014-07-01

    Since 2004, atmospheric carbon dioxide (CO2) is measured at the High Altitude Research Station Jungfraujoch by the division of Climate and Environmental Physics at the University of Bern (KUP) using a nondispersive infrared gas analyzer (NDIR) in combination with a paramagnetic O2 analyzer. In January 2010, CO2 measurements based on cavity ring down spectroscopy (CRDS) as part of the Swiss National Air Pollution Monitoring Network have been added by the Swiss Federal Laboratories for Materials Science and Technology (Empa). To ensure a smooth transition - a prerequisite when merging two datasets e.g. for trend determinations - the two measurement systems run in parallel for several years. Such a long-term intercomparison also allows identifying potential offsets between the two datasets and getting information about the compatibility of the two systems on different time scales. A good agreement of the seasonality as well as for the short-term variations was observed and to a lesser extent for trend calculations mainly due to the short common period. However, the comparison revealed some issues related to the stability of the calibration gases of the KUP system and their assigned CO2 mole fraction. It was possible to adapt an improved calibration strategy based on standard gas determinations, which lead to better agreement between the two data sets. By excluding periods with technical problems and bad calibration gas cylinders, the average hourly difference (CRDS - NDIR) of the two systems is -0.03 ppm ± 0.25 ppm. Although the difference of the two datasets is in line with the compatibility goal of ±0.1 ppm of the World Meteorological Organization (WMO), the standard deviation is still too high. A significant part of this uncertainty originates from the necessity to switch the KUP system frequently (every 12 min) for 6 min from ambient air to a working gas in order to correct short-term variations of the O2 measurement system. Allowing additionally for signal stabilization after switching the sample, an effective data coverage of only 1/6 for the KUP system is achieved while the Empa system has a nearly complete data coverage. Additionally, different internal volumes and flow rates between the two systems may affect observed differences.

  15. Comparison of continuous in situ CO2 observations at Jungfraujoch using two different measurement techniques

    Science.gov (United States)

    Schibig, M. F.; Steinbacher, M.; Buchmann, B.; van der Laan-Luijkx, I. T.; van der Laan, S.; Ranjan, S.; Leuenberger, M. C.

    2015-01-01

    Since 2004, atmospheric carbon dioxide (CO2) is being measured at the High Altitude Research Station Jungfraujoch by the division of Climate and Environmental Physics at the University of Bern (KUP) using a nondispersive infrared gas analyzer (NDIR) in combination with a paramagnetic O2 analyzer. In January 2010, CO2 measurements based on cavity ring-down spectroscopy (CRDS) as part of the Swiss National Air Pollution Monitoring Network were added by the Swiss Federal Laboratories for Materials Science and Technology (Empa). To ensure a smooth transition - a prerequisite when merging two data sets, e.g., for trend determinations - the two measurement systems run in parallel for several years. Such a long-term intercomparison also allows the identification of potential offsets between the two data sets and the collection of information about the compatibility of the two systems on different time scales. A good agreement of the seasonality, short-term variations and, to a lesser extent mainly due to the short common period, trend calculations is observed. However, the comparison reveals some issues related to the stability of the calibration gases of the KUP system and their assigned CO2 mole fraction. It is possible to adapt an improved calibration strategy based on standard gas determinations, which leads to better agreement between the two data sets. By excluding periods with technical problems and bad calibration gas cylinders, the average hourly difference (CRDS - NDIR) of the two systems is -0.03 ppm ± 0.25 ppm. Although the difference of the two data sets is in line with the compatibility goal of ±0.1 ppm of the World Meteorological Organization (WMO), the standard deviation is still too high. A significant part of this uncertainty originates from the necessity to switch the KUP system frequently (every 12 min) for 6 min from ambient air to a working gas in order to correct short-term variations of the O2 measurement system. Allowing additional time for signal stabilization after switching the sample, an effective data coverage of only one-sixth for the KUP system is achieved while the Empa system has a nearly complete data coverage. Additionally, different internal volumes and flow rates may affect observed differences.

  16. Comparison of continuous in-situ CO2 observations at Jungfraujoch using two different measurement techniques

    Directory of Open Access Journals (Sweden)

    M. F. Schibig

    2014-07-01

    Full Text Available Since 2004, atmospheric carbon dioxide (CO2 is measured at the High Altitude Research Station Jungfraujoch by the division of Climate and Environmental Physics at the University of Bern (KUP using a nondispersive infrared gas analyzer (NDIR in combination with a paramagnetic O2 analyzer. In January 2010, CO2 measurements based on cavity ring down spectroscopy (CRDS as part of the Swiss National Air Pollution Monitoring Network have been added by the Swiss Federal Laboratories for Materials Science and Technology (Empa. To ensure a smooth transition – a prerequisite when merging two datasets e.g. for trend determinations – the two measurement systems run in parallel for several years. Such a long-term intercomparison also allows identifying potential offsets between the two datasets and getting information about the compatibility of the two systems on different time scales. A good agreement of the seasonality as well as for the short-term variations was observed and to a lesser extent for trend calculations mainly due to the short common period. However, the comparison revealed some issues related to the stability of the calibration gases of the KUP system and their assigned CO2 mole fraction. It was possible to adapt an improved calibration strategy based on standard gas determinations, which lead to better agreement between the two data sets. By excluding periods with technical problems and bad calibration gas cylinders, the average hourly difference (CRDS ? NDIR of the two systems is ?0.03 ppm ± 0.25 ppm. Although the difference of the two datasets is in line with the compatibility goal of ±0.1 ppm of the World Meteorological Organization (WMO, the standard deviation is still too high. A significant part of this uncertainty originates from the necessity to switch the KUP system frequently (every 12 min for 6 min from ambient air to a working gas in order to correct short-term variations of the O2 measurement system. Allowing additionally for signal stabilization after switching the sample, an effective data coverage of only 1/6 for the KUP system is achieved while the Empa system has a nearly complete data coverage. Additionally, different internal volumes and flow rates between the two systems may affect observed differences.

  17. Improving carbon cycle models using inverse modelling techniques with in-situ measurements and satellite observations

    Science.gov (United States)

    Delahaies, Sylvain; Roulstone, Ian; Nichols, Nancy

    2014-05-01

    Improving our understanding of the carbon cycle is an important component of modelling climate and the Earth system, and a variety of inverse modelling techniques have been used to combine process models with different types of observational data. Model data fusion, or inverse modelling, is the process of best combining our under- standing of the dynamics of a system, observations and our prior knowledge of the state of the system. We consider a simple model for the carbon budget allocation for terrestrial ecosystems, the Data Assimilation-Linked Ecosystem model (DALEC). DALEC is a box model simulating a large range of processes occurring at different time scales from days to millennia. Eddy covariance measurements of net ecosystem exchange of CO2 have been used intensively for over a decade to confront DALEC with real data to estimate model parameters and quantify uncertainty of the model predictions. The REgional FLux Estimation eXperiment (REFLEX), compared the strengths and weaknesses of various inverse modelling strategies (MCMC, ENKF) to estimate parameters and initial stocks for DALEC; most results agreed on the fact that parameters and initial stocks directly related to fast processes were best estimated with narrow confidence intervals, whereas those related to slow processes were poorly estimated with very large uncertainties. While other studies have tried to overcome this difficulty by adding complementary data streams or by considering longer observation windows no systematic analysis has been carried out so far to explain the large differences among results of REFLEX. One of the merits of DALEC is its simplicity that facilitates close mathematical scrutiny. Using variational techniques we quantify the ill-posedness of the inverse problem and we discuss various regularisation techniques. Using the tangent linear model we study the information content of multiple data sources and show how these multiple data sources help constraining initial carbon stocks and parameters.

  18. Assaying depleted uranium in bones in-situ using a non-invasive x-ray fluorescence technique

    International Nuclear Information System (INIS)

    The occupational exposure to uranium associated with milling and fabrication of depleted uranium is presently assessed from bioassay of urine samples. The evaluation of the body-burden of uranium from urine analysis has many difficulties and uncertainties associated with accounting for the bio-transport of inhaled uranium particles from the lungs, to absorption in the blood and excretion through the kidneys. The chemical toxicity of uranium and other transuranic elements is not fully understood, partially because of the difficulty of assessing the body burden of these metals in-situ. The transuranic elements are known to be deposited and retained in bone. A non-invasive X-ray fluorescence technique has been developed to assay the depleted uranium in bones in-situ. The K-shell electrons in uranium, which have a binding energy of 115.6 keV, are excited by the 122 and 136 keV gamma rays from a Co-57 source. A liquid N2 cooled intrinsic Ge-detector is employed to measure the characteristic K fluorescence from the uranium as well as the coherently scattered gamma rays from the Co-57 source. The quantity of uranium in the bone is determined from the number of K fluorescence events extracted from the measured scattered photon spectrum. In addition, the bone mineral mass is determined from the number of coherently scattered gamma rays, permitting the assay of uranium to be pressed in terms of micrograms per unit mass bone. Using this system it was possible to measuUsing this system it was possible to measure molar concentrations of uranium with high precision and reproducibility

  19. Application of hot patch technique for stabilized post-CHF test in a rod bundle

    International Nuclear Information System (INIS)

    Convective boiling beyond critical-heat-flux (CHF) with nonequilibrium between the phases is encountered in a number of applications such as cryogenic systems, steam generators, and in the hypothetical nuclear reactor loss-of-coolant accidents. In a vertical geometry the CHF location may progress up or down depending on the operating conditions. As a result, the phenomena is time dependent and hard to measure accurately. Several experimental studies of such phenomena in a single tube were conducted using a hot-patch technique to arrest the quench front, and generate stabilized post-CHF conditions in the test section. This paper describes the first successful application of the hot-patch technique in rod bundles. Design requirements for the 3X3 rod bundle test section with a heated shroud, and hot patch are described. Preliminary experiments are also presented and show that the quench front can be stabilized with the help of the present hot-patch design for rod bundles. The paper also describes the techniques used for measuring nonequilibrium vapor temperatures, and pressure drop in a high temperature two-phase flow

  20. Monitoring Nitrate, Chlorophyll, and CDOM Cycling in a Reservoir using In Situ Mapping Techniques

    Science.gov (United States)

    OConnor, J.; Showers, W. J.; Osburn, C. L.; DeMaster, D. J.

    2013-12-01

    Degradation of surface waters due to increased nutrient loading and subsequent eutrophication is a persistent problem on a global scale. Expanding human populations and their associated development create increased pressure on local watersheds in terms of both point and non-point source pollution. In this study a suite of in situ sensors measuring nitrate concentration, chlorophyll a concentration (Chl a), and chromophoric dissolved organic material (CDOM) fluorescence were deployed from a rapidly moving boat (~32 km/h) in order to identify sources of nutrients and CDOM, and to determine their relationship to eutrophication symptoms in Falls Lake, North Carolina. In addition, water samples were collected throughout the lake and from tributaries of interest for laboratory analysis. Results indicated the three main tributaries at the north end of the lake were the important contributors of both nitrate and CDOM. While two of the three were degraded due to significant effluent discharge from Waste Water Treatment Plants, the third appeared to be impacted by diffuse nutrient sources. However, atmospheric deposition of nitrate and ammonium exceeded tributary input, and the net nutrient loading to the lake was dominated by sediment release of both ammonium and phosphate. No direct relationship between nitrate and Chl a concentrations was observed, but bays that sewage impacted rivers emptied into displayed elevated Chl a values. Water samples from both the lake and streams were analyzed for stable isotopic analysis of ?15N and ?18O composition and were consistent with waste as the primary source of nitrate. Samples were also analyzed for CDOM absorbance and fluorescence through the creation of Excitation and Emission Matrices (EEMs) and the development of a nine component PARAFAC model. Fluorescence values consistently declined from the north end of the lake to the southern end at the dam and water treatment plant intake. Absorbance values at 254 nm (a254) also showed a decreasing trend from north to south, while SR increased. The loss of absorption could have been caused by photobleaching, however, a hydrologic modeling experiment demonstrated that this change in optical character was actually due to mixing of un-polluted tributary and rain water with water from the main tributaries at the north end. At the southern end of the lake, adjacent to the water treatment plant intake, a series of depth profiles were made that revealed a stratified water column during summer months. There was evidence of production of CDOM in the anoxic hypolimnion that appeared to be linked to an increase in Chl a concentration. There was also a significant increase in a254 and a decrease in SR that suggested CDOM was released from the sediments in the hypolimnion. This study showed that the north end of the lake suffered from persistent eutrophication symptoms. However, as the water traveled south to the two exit points at the dam and the water treatment plant, water quality improved.

  1. Influence of in situ synthesized TiC on thermal stability and corrosion behavior of Zr60Cu10Al15Ni15 amorphous composites

    Science.gov (United States)

    Geng, Jiwei; Teng, Xinying; Zhou, Guorong; Leng, Jinfeng; Zhao, Degang

    2014-03-01

    In situ synthesized TiC particles were prepared by a thermal explosion method. Adding “in situ synthesized” TiC into Zr60Cu10Al15Ni15 glass matrix to obtain amorphous matrix composites was achieved. The corrosion behavior of Zr60Cu10Al15Ni15 amorphous composites was evaluated using potentiodynamic polarization measurements in 3.5 wt% NaCl solution at room temperature. The results show that the microhardness and thermal stability are improved apparently, while the TiC (?0.6 wt%) does not significantly affect the supercooled liquid behavior. Moreover, the corrosion resistance is improved apparently because the nanocrystals accelerate the diffusion of passive elements for faster formation of the protective passive film at nanocrystals/amorphous interfaces. However, when the TiC content is more than 0.6 wt%, both glass forming ability and corrosion resistance are reduced significantly.

  2. Influence of in situ synthesized TiC on thermal stability and corrosion behavior of Zr60Cu10Al15Ni15 amorphous composites

    International Nuclear Information System (INIS)

    In situ synthesized TiC particles were prepared by a thermal explosion method. Adding “in situ synthesized” TiC into Zr60Cu10Al15Ni15 glass matrix to obtain amorphous matrix composites was achieved. The corrosion behavior of Zr60Cu10Al15Ni15 amorphous composites was evaluated using potentiodynamic polarization measurements in 3.5 wt% NaCl solution at room temperature. The results show that the microhardness and thermal stability are improved apparently, while the TiC (?0.6 wt%) does not significantly affect the supercooled liquid behavior. Moreover, the corrosion resistance is improved apparently because the nanocrystals accelerate the diffusion of passive elements for faster formation of the protective passive film at nanocrystals/amorphous interfaces. However, when the TiC content is more than 0.6 wt%, both glass forming ability and corrosion resistance are reduced significantly

  3. A novel rocket-based in-situ collection technique for mesospheric and stratospheric aerosol particles

    Directory of Open Access Journals (Sweden)

    W. Reid

    2012-11-01

    Full Text Available A technique for collecting aerosol particles between altitudes of 85 and 17 km is described. Collection probes are ejected from a sounding rocket allowing for multi-point measurements. Each probe is equipped with 110 collection samples that are 3 mm in diameter. The collection samples are one of three types: standard transmission electron microscopy carbon grids, glass fibre filter paper or silicone gel. Each collection sample is exposed over a 50 m to 5 km height range with a total of 45 separate ranges. Post-flight electron microscopy gives size-resolved information on particle number, shape and elemental composition. Each collection probe is equipped with a suite of sensors to capture the probe's status during the fall. Parachute recovery systems along with GPS-based localization ensure that each probe can be located and recovered for post-flight analysis.

  4. A well logging technique for the in situ determination of 90Sr

    International Nuclear Information System (INIS)

    A technique for determining the 90Sr concentration in soils and sediments by measurements of bremsstrahlung radiation in the energy range 60-236 keV with a large intrinsic germanium diode capable of logging wells as small as 3'' in diameter is described. Correction are made for changing background levels as a function of depth and for interferences from any other radionuclides present. A 90Sr concentration as low as 9 nCi cm-3 can be measured in only 10 s in typical fission product gamma-ray activities of 100 nCi cm-3. If no interfering radionuclides are present, 90Sr concentrations of -3 can be determined. The relationship between detector size and sensitivity is discussed. Detection limits are given for different counting times as a function of interfering activity levels. (orig.)

  5. Voltage stability constrained ATC computations in deregulated power system using novel technique

    Directory of Open Access Journals (Sweden)

    P. Gopi Krishna

    2008-12-01

    Full Text Available The voltage stability constrained Available Transfer Capability (ATC computations are obtained on IEEE 9-bus by running load flow until the voltage collapse point is achieved by enhancing the load in steps with constant power factor. These results are used to train the Neural Network by using Radial Basis Function Neural Network (RBFN technique. The comparative results of convergence method, L-index method and RBFN network are presented in this study. The results are certainly useful in an online environment of deregulated power system in view of computational simplicity, time and computer memory.

  6. Application Of Differential Pulse Cathodic Stripping Voltammetric Technique In Studying Stability Of Aflatoxins

    OpenAIRE

    Yaacob, Mohammad Hadzri; Yusoff, Abdull Rahim Hj. Mohd.; Ahamad, Rahmalan; Marpongahtun

    2009-01-01

    A stability studies of aflatoxins (AFB1, AFB2, AFG1 and AFG2 ) in Britton-Robinson buffer (BRb) using a Differential Pulse Cathodic Stripping Voltammetric (DPCSV) technique is described. The DPCSV was performed by cathodic potential scan through within the range of -950 to -1400 mV with 80s accumulation time using a BRb at pH 9.0 as the supporting electrolyte. The sampels were exposed for 0 to 8 hrs to normal laboratory condition before being scanned under optimised voltammetric parameters...

  7. The study of the stability of passive films using potentiostatic-galvanostatic transient technique

    International Nuclear Information System (INIS)

    An on-line measurement system for the potentiostatic-galvanostatic (P-G) transient response of passive metals was established. A mathematical model for the P-G response curves in the case of the pitting was set up. Using the Monte Carlo method the electrochemical parameters which characterized the stability of the passive films were calculated from the sampling data of the response curves. The results for some steels in sodium chloride solution measured by this technique are presented and the features of the breakdown of passive films for different steels are discussed. (author)

  8. Stability Study of Filtering Techniques in Pictures of mini-MIAS Database

    International Nuclear Information System (INIS)

    The study of filtering techniques applied to medical imaging is particularly important because it can be decisive for an accurate diagnosis. This work aims to study the stability of Fuzzy Peer Group Averaging filter when applied to mammographic images of different nature in relation to the type of tissue abnormality found and diagnosis. The results show that the filter is effective, because obtained a PSNR value of 27 by comparing the filtered image with the original, and a value of 17 by comparing the filtered image with contaminated with noise. Also show that the filter will behave properly regardless of the image characteristics. (Author)

  9. Trace Metals in Groundwater and the Vadose Zone Calcite: In Situ Containment and Stabilization of Strontium-90 and Other Divalent Metals and Radionuclides at Arid West DOE

    International Nuclear Information System (INIS)

    Radionuclide and metal contaminants such as strontium-90 are present beneath U.S. Department of Energy (DOE) lands in both the groundwater (e.g., 100-N area at Hanford, WA) and vadose zone (e.g., Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory). In situ containment and stabilization of these contaminants is a cost-effective treatment strategy. However, implementing in situ containment and stabilization approaches requires definition of the mechanisms that control contaminant sequestration. We are investigating the in situ immobilization of radionuclides or contaminant metals (e.g., strontium-90) by their facilitated co-precipitation with calcium carbonate in groundwater and vadose zone systems. Our facilitated approach, shown schematically in Figure 1, relies upon the hydrolysis of introduced urea to cause the acceleration of calcium carbonate precipitation (and trace metal co-precipitation) by increasing pH and alkalinity. Subsurface urea hydrolysis is catalyzed by the urease enzyme, which may be either introduced with the urea or produced in situ by ubiquitous subsurface urea hydrolyzing microorganisms. Because the precipitation process tends to be irreversible and many western aquifers are saturated with respect to calcite, the co-precipitated metals and radionuclides will be effectively removed from the aqueous phase over the long-term. Another advantage of the ureolysis approach is that the ammonium ions produced by the reaction can exchange with radionuclides sorbed to subsurface minerals, thereby enhancing the availability of the radionuclides for re-capture in a more stable solid phase (co-precipitation rather than adsorption)

  10. Techniques for the measurement of moments of nuclei far from stability

    International Nuclear Information System (INIS)

    Techniques for the measurement of static moments of nuclei far from stability formed with heavy ion fusion evaporation reactions are discussed. Integral perturbed angular correlation techniques have been used to measure g-factors in 168W110Pd(61Ni,3n)168W at 225 MeV with a beam from the Stony Brook Superconducting Linac. The W was implanted in an polarized Fe host, and the rotation of the angular distribution of the ? radiation was detected with Ge spectrometer. The g factor of the 12+ state just above the backbend was found to be -0.212(67), consistent with a backbend caused by a pair of i/sub 13/s/ neutrons. The g-factor of the first 2+ state was found to be +0.254(55)

  11. Stability of revision acetabular components using the rim-fit technique.

    Science.gov (United States)

    Lang, Jason E; Bono, James V; Whiddon, David R; Salyapongse, Aaron K; Moezzi, Darius M; Smith, Eric L

    2010-01-01

    Use of the rim-fit technique in revision acetabular surgery was reviewed for 20 hips in 18 patients. Defects at revision surgery included isolated medial segmental and global cavitary deficiencies with largely intact peripheral rim. A cementless acetabular component is placed to achieve a press-fit against the bony acetabular rim after morselized allograft and/or autograft was placed behind the cup. The average follow-up period was 68.3 months (5.7 years) (range, 27-112 months). Cup migration was assessed using digital radiography. Average vertical migration was 1.02 mm superiorly, and average horizontal migration was 0.8 mm medially. The abduction angle changed on average by 0.25 degrees. Use of the rim-fit technique for treatment of cavitary acetabular defects is associated with component stability and minimal component migration. PMID:19056229

  12. In-situ measurements of dynamic irradiation effects using optical techniques

    International Nuclear Information System (INIS)

    The feasibility of applying optical fibers to the in-core measurement in nuclear reactors was examined by using the material testing reactor JMTR in Japan Atomic Energy Research Institute. For the research on the development of the materials and fuel with excellent radiation resistance, it is necessary to develop the system which measures irradiation effect in nuclear reactors on real time, and optical measurement is the most desirable technique. Regarding optical fibers, it has been made clear according to the experience in the past that the transmission characteristics deteriorate remarkably due to irradiation as color centers are introduced in large quantity into the fiber core due to the ionization effect of radiation. The use of optical fibers in intense radiation fields and the behavior of optical fibers in nuclear reactors are reported. The radiation-resistant fibers which were developed showed the very good transmission characteristics in the long wavelength region exceeding 750 nm. In short wavelength region, the characteristics in visible region were worsened remarkably by large absorption. (K.I.)

  13. Novel in situ gelling ocular films for the opioid growth factor-receptor antagonist-naltrexone hydrochloride: fabrication, mechanical properties, mucoadhesion, tolerability and stability studies.

    Science.gov (United States)

    Abdelkader, Hamdy; Pierscionek, Barbara; Alany, Raid G

    2014-12-30

    Naltrexone hydrochloride (NTX) is an innovative drug used in ophthalmology for treatment of ocular surface diseases such as impaired corneal wound healing and severe dry eye. Poor chemical stability has been a major limitation for development of NTX in solution form. The aim of this study was to develop and characterise NTX in situ ocular films for enhanced chemical stability and improved ocular tolerability. The films were prepared from different amorphous polymers and characterised for physicochemical compatibility, moisture-sorption, surface pH, mechanical properties, sterilisability, surface morphology, mucoadhesion, in vitro release, conjunctival irritation and accelerated stability at 40°C/75% relative humidity for 3 months. Glycerin (GLY)-plasticised films exhibited significantly better mechanical properties, compared with polyethylene glycol (PEG) 400 and triethylcitrate (TEC)-plasticised formulations. Superior mucoadhesion was recorded for F7 and F9 plasticised with GLY and PEG 400, respectively. The stability of NTX was significantly enhanced more than 18-times, compared with the solution form. Combination of carboxymethylcellulose sodium (CMC) and sodium alginate (ALG) in a film formulation demonstrated minimal % moisture sorption, good mechanical properties, in vitro release, excellent chemical stability and minimal conjunctival irritation lending them as promising ocular formulations. PMID:25445974

  14. Marital stability and quality in families created by assisted reproduction techniques: a follow-up study.

    Science.gov (United States)

    Blake, L; Casey, P; Jadva, V; Golombok, S

    2012-12-01

    An increasing number of children are being born with the use of assisted reproduction techniques such as donor insemination, egg donation and surrogacy. There have been concerns that the use of these third-party reproduction techniques may have a negative effect on the quality of the relationship between the mother and father. Marital stability and quality was examined in a UK sample of donor insemination, egg donation and surrogacy families and families in which children were naturally conceived. Interview and questionnaire assessments of marital stability and quality were collected from mothers and fathers over five time points, when the children in the families were aged 1, 2, 3, 7 and 10. Of those families who participated when children were 10years old, a minority of couples in each family type had divorced/separated and few differences emerged between the different family types in terms of mothers' or fathers' marital quality. Despite concerns, couples in families created by donor insemination, egg donation and surrogacy were found to be functioning well. PMID:23063821

  15. A new technique to monitor the long-term stability of an optoelectronic oscillator.

    Science.gov (United States)

    Pham, Toan Thang; Ledoux-Rak, Isabelle; Journet, Bernard; Vu, Van Yem

    2015-01-01

    The main advantage of an optoelectronic oscillator (OEO) is the ability to synthesize directly very high spectral purity frequency in microwave domain. Beside applications in radar, telecommunication and satellite systems, OEO can also be used in sensor applications such as refractive index or distance measurements. However, the long-term stability of the OEO is easily affected by ambient environment variations. The optical fiber loop effective refractive index varies corresponding to its surrounding temperature changes. Consequently, it makes the optical transmission path inside the fiber loop differ from the initial state, leading to oscillation frequency changes. To stabilize the single loop OEO, it is essential to keep its high Q elements in a well-controlled thermal box as much as possible. Unfortunately, in the real implementation condition, this requirement is difficult to be satisfied. In this paper, we present a new technique to estimate the oscillation frequency variation under the room temperature by using a vector network analyzer (VNA). Experimental results show a good correlation between OEO oscillation frequency drift and the phase measured by the VNA. This technique can be implemented to apply corrections when using the OEO as a distance variation or a refractive index measurement tool. We also tracked the temperature of the fiber loop at the same time with the VNAbased experiment to compare two correlations of temperature and phase with OEO oscillation frequency.

  16. Intrinsic stress in ZrN thin films: Evaluation of grain boundary contribution from in situ wafer curvature and ex situ x-ray diffraction techniques

    Energy Technology Data Exchange (ETDEWEB)

    Koutsokeras, L. E. [Departement Physique et Mecanique des Materiaux, Institut Pprime, CNRS-Universite de Poitiers-ENSMA, UPR 3346, SP2MI, Teleport 2, Bd M et P Curie, F 86962 Chasseneuil-Futuroscope (France); Department of Materials Science and Engineering, University of Ioannina, Ioannina 45110 (Greece); Abadias, G. [Departement Physique et Mecanique des Materiaux, Institut Pprime, CNRS-Universite de Poitiers-ENSMA, UPR 3346, SP2MI, Teleport 2, Bd M et P Curie, F 86962 Chasseneuil-Futuroscope (France)

    2012-05-01

    Low-mobility materials, like transition metal nitrides, usually undergo large residual stress when sputter-deposited as thin films. While the origin of stress development has been an active area of research for high-mobility materials, atomistic processes are less understood for low-mobility systems. In the present work, the contribution of grain boundary to intrinsic stress in reactively magnetron-sputtered ZrN films is evaluated by combining in situ wafer curvature measurements, providing information on the overall biaxial stress, and ex situ x-ray diffraction, giving information on elastic strain (and related stress) inside crystallites. The thermal stress contribution was also determined from the in situ stress evolution during cooling down, after deposition was stopped. The stress data are correlated with variations in film microstructure and growth energetics, in the 0.13-0.42 Pa working pressure range investigated, and discussed based on existing stress models. At low pressure (high energetic bombardment conditions), a large compressive stress is observed due to atomic peening, which induces defects inside crystallites but also promotes incorporation of excess atoms in the grain boundary. Above 0.3-0.4 Pa, the adatom surface mobility is reduced, leading to the build-up of tensile stress resulting from attractive forces between under-dense neighbouring column boundary and possible void formation, while crystallites can still remain under compressive stress.

  17. Development of Ground-Based Auroral Photometry Techniques Using In-Situ Electron Precipitation Measurements from the GREECE Mission

    Science.gov (United States)

    Grubbs, G. A., II; Samara, M.; Michell, R.; Hampton, D.

    2014-12-01

    The Ground-to-Rocket Electrodynamics-Electrons Correlative Experiment (GREECE) mission successfully launched from Poker Flat, Alaska on 03 March 2014 at 11:09:50 UT and reached an apogee of approximately 335 km during a luminous auroral event. Multiple ground-based electron-multiplying charge-coupled device (EMCCD) imagers were positioned at Venetie, Alaska and aimed along magnetic zenith in order to observe the brightness of different auroral emission lines (427.8, 557.7, and 844.6 nm with a 47 degree field of view) at the magnetic footpoint of the payload, near apogee. Emission line brightness data are presented at the footpoint of the rocket flight and correlated with electron characteristics taken by the Acute Precipitating Electron Spectrometer (APES) on-board instrument. Ratios of different auroral emission lines are also compared to previously published methods and models. This research aims to describe the auroral emissions produced from a known precipitating electron distribution, such that we can more accurately use ground-based imaging and photometry to infer the characteristics of the precipitating electrons. These techniques can then be applied over larger scales and longer times, when only multi-spectral imaging data are available with no corresponding in situ data.

  18. Tuning of colossal dielectric constant in gold-polypyrrole composite nanotubes using in-situ x-ray diffraction techniques

    Energy Technology Data Exchange (ETDEWEB)

    Sarma, Abhisakh; Sanyal, Milan K., E-mail: milank.sanyal@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India)

    2014-09-15

    In-situ x-ray diffraction technique has been used to study the growth process of gold incorporated polypyrrole nanotubes that exhibit colossal dielectric constant due to existence of quasi-one-dimensional charge density wave state. These composite nanotubes were formed within nanopores of a polycarbonate membrane by flowing pyrrole monomer from one side and mixture of ferric chloride and chloroauric acid from other side in a sample cell that allows collection of x-ray data during the reaction. The size of the gold nanoparticle embedded in the walls of the nanotubes was found to be dependent on chloroauric acid concentration for nanowires having diameter more than 100 nm. For lower diameter nanotubes the nanoparticle size become independent of chloroauric acid concentration and depends on the diameter of nanotubes only. The result of this study also shows that for 50 nm gold-polypyrrole composite nanotubes obtained with 5.3 mM chloroauric acid gives colossal dielectric constant of about 10{sup 7}. This value remain almost constant over a frequency range from 1Hz to 10{sup 6} Hz even at 80 K temperature.

  19. Stabilized methods and post-processing techniques for Darcy flow and related problems

    International Nuclear Information System (INIS)

    In this paper we present a review of stabilized methods and post-processing techniques for Darcy flow problems, with particular emphasis in the miscible displacement model. The system of partial differential equations governing the miscible displacement consists of an elliptic system coming from the conservation of mass and Darcy's law and a nonlinear transport equation expressing the conservation of the injected fluid (concentration). The main difficulties are related to the evaluation of the primary unknowns of the elliptic equation (pressure) and their spatial derivatives by Darcy's law (velocity) and the coupling with the convection dominated transport equation. Finite element solutions for this problem have been obtained using mixed methods for the pressure/gradient problem combined with the modified method of characteristics. However, this approach involves different interpolation schemes for pressure, velocity and concentration. In order to overcome the difficulties associated with the previous schemes, we have been working in the development of finite element formulations where all variables are interpolated by equal-order functions. To recover accurate velocity approximations we have developed new global and local post-processing techniques. These post-processing techniques consist in solving the elliptic problem for pressure and then computing velocity considering residual forms of Darcy's law with the known pressure, the mass balance equation and the irrota, the mass balance equation and the irrotationality condition. These post-processing techniques are then combined with semidiscrete or space-time SUPG or GLS formulations with shock capturing. We also address in this paper issues related to the improvement of computational efficiency of our methods. Among then we will show reduced integration techniques with hourglass control for the elliptic, post-processing and transport equations, its association to superconvergent techniques for gradient recovery, adaptive time stepping strategies based on feedback control theory and parallel element-by-element strategies. Extensive numerical results will show the effectiveness of our approach. (author)

  20. Elaboration of Nanocomposites Based on Poly (Ethyl Methacrylate-co-Acrylonitrile by In Situ Polymerization Using an Algerian Bentonite. Thermal Stability and Kinetic Study

    Directory of Open Access Journals (Sweden)

    Djadoun S.

    2012-08-01

    Full Text Available This contribution focuses on the synthesis and characterization of nanocomposites based on poly (ethyl methacrylate-co-acrylonitrile (PEMAN and different loadings of an organically modified bentonite from Algeria prepared via in situ polymerization. TEM images and X-ray patterns revealed that depending on the loading of this clay, intercalated or partially exfoliated nanocomposites were obtained. These nanocomposites showed an increase in their glass transition temperature compared to the pure copolymer as investigated by Differential Scanning Calorimetry and improved thermal stability as evidenced by Thermogravimetric analysis and kinetics of their thermal degradation. Activation energies (Ea of thermal decomposition of PEMAN and its nanocomposites were determined by Flynn–Wall–Ozawa and Kissinger-Akahira-Sunose methods. The changes in (Ea value with the level of conversion suggest a significant improved thermal stability of the nanocomposites compared to the copolymer matrix.

  1. Wheat improvement for drought resistance and yield stability using mutation techniques

    International Nuclear Information System (INIS)

    The main problem of plant breeding is development of varieties with optimal combination of high drought resistance, productivity and yield stability in varying unfavorable conditions. It is especially important for Kazakhstan, the main agricultural areas of which are located in the arid zones characterized by moisture supply deficiency. Mutation techniques have proven to be valuable technique in enhancing crop genetic diversity for selecting new variants with traits of economic importance. Therefore we used M2 population of spring bread wheat var. Kazakhstastanskaya 126 treated by nicotinic acid extracted from tobacco leaves 0,01% and 0,1%, respectively. Based on germplasm of M2 there was developed genotype Grekum 476 having changes in leaf shape such as rolling of flag leaf. This trait protects plant from intensive insolation and overheating, prevent losses of water and provide long-term function of leaves and therefore it was used for wheat improvement of commercial cultivars. The objective of this study is the analysis of genotype x environment interaction (GEI) and evaluation of the donors of drought resistance and stability among the winter wheat genotypes. Experimental material has been grown in 2004-2006 at thee contrasting ecological zones including irrigated and non-irrigated conditions. To analyze GEI the method Tai (1971) was used. Drought susceptibility index was used for drought resistance assessment (Fisher and Maurer, 1978). The obsessment (Fisher and Maurer, 1978). The objects of study were wheat genotypes with inserted leaf rolling trait (Grekum 476, Hostianum 88, Albidum 109, Miras), and varieties developed in Kazakhstan and the Ukraine, that differ in the level of productivity and drought resistance. It was found that rolling leaf trait in the main source Grekum 476 is controlled by two dominant Rl-genes. The genotypes with Rl-genes able to conserve high leaf water potential as the tendency for greater leaf hydration seems to be a consequence of osmotic adjustment connected to drought resistance has a high level of osmotic adjustment. Analysis of GEI allowed differentiating experimental material by the level of stability. The best stability observed in donors of RL-genes - Grekum 476 and Album 109. The biggest level of field drought resistance was observed in varieties Bogarnaya 56, Krasnovodopadskaya 210 and Grekum 476, which were high yielding in stress environments. It is known that ecological reaction of adaptability - the rolling of leaves, is the characteristics for the varieties with Rl-genes. This trait allows using water economically by limitation of transpiration, to regulate plant water balance more efficiently. Obviously, the high level of drought resistance of Grekum 476 has been provided by the presence in its genotype of Rl-genes. Thus, the use of chemical mutagen allowed widening the spectrum of genetic variability of wheat germplasm. In comparison to the origin cultivar Kazakhstanskaya 126, their mutant derivatives demonstrated higher level of drought resistance and yield stability. These germplasms were ranged by the level of yield stability and drought resistance in wheat. The relationship between field drought resistance and ecological parameters of stability was found. (author)

  2. Advanced Techniques for Assessment of Postural and Locomotor Ataxia, Spatial Orientation, and Gaze Stability

    Science.gov (United States)

    Wall, Conrad., III

    1999-01-01

    In addition to adapting to microgravity, major neurovestibular problems of space flight include postflight difficulties with standing, walking, turning corners, and other activities that require stable upright posture and gaze stability. These difficulties inhibit astronauts' ability to stand or escape from their vehicle during emergencies. The long-ter7n goal of the NSBRI is the development of countermeasures to ameliorate the effects of long duration space flight. These countermeasures must be tested with valid and reliable tools. This project aims to develop quantitative, parametric approaches for assessing gaze stability and spatial orientation during normal gait and when gait is perturbed. Two of this year's most important findings concern head fixation distance and ideal trajectory analysis. During a normal cycle of walking the head moves up and down linearly. A simultaneous angular pitching motion of the head keeps it aligned toward an imaginary point in space at a distance of about one meter in front of a subject and along the line of march. This distance is called the head fixation distance. Head fixation distance provides the fundamental framework necessary for understanding the functional significance of the vestibular reflexes that couple head motion to eye motion. This framework facilitates the intelligent design of counter-measures for the effects of exposure to microgravity upon the vestibular ocular reflexes. Ideal trajectory analysis is a simple candidate countermeasure based upon quantifying body sway during repeated up and down stair stepping. It provides one number that estimates the body sway deviation from an ideal sinusoidal body sway trajectory normalized on the subject's height. This concept has been developed with NSBRI funding in less than one year. These findings are explained in more detail below. Compared to assessments of the vestibuo-ocular reflex, analysis of vestibular effects on locomotor function is relatively less well developed and quantified. We are improving this situation by applying methodologies such as nonlinear orbital stability to quantify responses and by using multivariate statistical approaches to link together the responses across separate tests. In this way we can exploit the information available and increase the ability to discriminate between normal and pathological responses. Measures of stability and orientation are compared to measures such as dynamic visual acuity and with balance function tests. The responses of normal human subjects and of patients having well documented pathophysiologies are being characterized. When these studies are completed, we should have a clearer idea about normal and abnormal patterns of eye, head, and body movements during locomotion and their stability in a wide range of environments. We plan eventually to use this information to validate the efficacy of candidate neurovestibular and neuromuscular rehabilitative techniques. Some representative studies made during this year are summarized.

  3. Demonstration of the stabilization technique for nonplanar optical resonant cavities utilizing polarization

    Science.gov (United States)

    Akagi, T.; Araki, S.; Funahashi, Y.; Honda, Y.; Miyoshi, S.; Okugi, T.; Omori, T.; Shimizu, H.; Sakaue, K.; Takahashi, T.; Tanaka, R.; Terunuma, N.; Uesugi, Y.; Urakawa, J.; Washio, M.; Yoshitama, H.

    2015-04-01

    Based on our previously developed scheme to stabilize nonplanar optical resonant cavities utilizing polarization caused by a geometric phase in electromagnetic waves traveling along a twisted path, we report an application of the technique for a cavity installed in the Accelerator Test Facility, a 1.3-GeV electron beam accelerator at KEK, in which photons are generated by laser-Compton scattering. We successfully achieved a power enhancement of 1200 with 1.4% fluctuation, which means that the optical path length of the cavity has been controlled with a precision of 14 pm under an accelerator environment. In addition, polarization switching utilizing a geometric phase of the nonplanar cavity was demonstrated.

  4. Advanced kinetics for calorimetric techniques and thermal stability screening of sulfide minerals

    International Nuclear Information System (INIS)

    Thermal methods of analysis such as differential scanning calorimetry (DSC) provide a powerful methodology for the study of solid reactions. This paper proposes an improved thermal analysis methodology for thermal stability investigation of complex solid-state reactions. The proposed methodology is based on differential iso-conversional approach and involves peak separation, individual peak analysis and combination of isothermal/non-isothermal DSC measurements for kinetic analysis and prediction. The proposed thermal analysis, which coupled with Mineral Libration Analyzer (MLA) technique was employed to investigate thermal behavior of sulfide mineral oxidation. The importance of various experimental variables such as particle size, heating rate and atmosphere were investigated and discussed. The information gained from such an advanced thermal analysis method is useful for scale-up processes with potential of significant savings in plant operations, as well as in mitigating adverse environmental and safety issues arising from handling and storage of sulfide minerals.

  5. Experimental analysis of mechanical response of stabilized occipitocervical junction by 3D mark tracking technique

    Directory of Open Access Journals (Sweden)

    Brémand F.

    2010-06-01

    Full Text Available This study is about a biomechanical comparison of some stabilization solutions for the occipitocervical junction. Four kinds of occipito-cervical fixations are analysed in this work: lateral plates fixed by two kinds of screws, lateral plates fixed by hooks and median plate. To study mechanical rigidity of each one, tests have been performed on human skulls by applying loadings and by studying mechanical response of fixations and bone. For this experimental analysis, a specific setup has been developed to impose a load corresponding to the flexion-extension physiological movements. 3D mark tracking technique is employed to measure 3D displacement fields on the bone and on the fixations. Observations of displacement evolution on the bone according to the fixation show different rigidities given by each solution.

  6. On the Decay Ratio Determination in BWR Stability Analysis by Auto-Correlation Function Techniques

    International Nuclear Information System (INIS)

    A novel auto-correlation function (ACF) method has been investigated for determining the oscillation frequency and the decay ratio in BWR stability analyses. The neutron signals are band-pass filtered to separate the oscillation peak in the power spectral density (PSD) from background. Two linear second-order oscillation models are considered. These models, corrected for signal filtering and including a background term under the peak in the PSD, are then least-squares fitted to the ACF of the previously filtered neutron signal, in order to determine the oscillation frequency and the decay ratio. Our method uses fast Fourier transform techniques with signal segmentation for filtering and ACF estimation. Gliding 'short-term' ACF estimates on a record allow the evaluation of uncertainties. Numerical results are given which have been obtained from neutron data of the recent Forsmark I and Forsmark II NEA benchmark project. Our results are compared with those obtained by other participants in the benchmark project. The present PSI report is an extended version of the publication K. Behringer, D. Hennig 'A novel auto-correlation function method for the determination of the decay ratio in BWR stability studies' (Behringer, Hennig, 2002)

  7. Synthesis, microstructure and mechanical properties of ceria stabilized tetragonal zirconia prepared by spray drying technique

    International Nuclear Information System (INIS)

    Ceria stabilized zirconia powders with ceria concentration varying from 6 to 16 mol% were synthesized using spray drying technique. Powders were characterized for their particle size distribution and specific surface area. The dense sintered ceramics fabricated using these powders were characterized for their microstructure, crystallite size and phase composition. The flexural strength, fracture toughness and micro-hardness of sintered ceramics were measured. High fracture toughness and flexural strength were obtained for sintered bodies with 12 mol% of CeO2. Flexural strength and fracture toughness were dependent on CeO2 concentration, crystallite size and phase composition of sintered bodies. Correlation of data has indicated that the transformable tetragonal phase is the key factor in controlling the fracture toughness and strength of ceramics. It has been demonstrated that the synthesis method is effective to prepare nanocrystalline tetragonal ceria stabilized zirconia powders with improved mechanical properties. Ce-ZrO2 with 20 wt% alumina was also prepared with flexural strength, 1200 MPa and fracture toughness 9.2 MPa?m. (author)

  8. In-situ characterization of gamma/gamma ' lattice stability in a nickel-base superalloy by neutron diffraction

    OpenAIRE

    Wang, DQ; Babu, SS; Payzant, EA; Radaelli, PG; Hannon, AC

    2001-01-01

    Microstructural stability for nickel-base superalloys were studied to investigate between lattice stability, diffusion and thermal treatments. The volume fraction of precipitates, phase composition and lattice mismatch between precipitates and matrix were found. Neutron scattering experiments were carried out using a diffractometer. An individual diffraction spectrum of sufficient resolution was obtained in one minute interval.

  9. Multi-platform in-situ and remote sensing techniques to derive Saharan dust properties during AMISOC-TNF 2013

    Science.gov (United States)

    Córdoba-Jabonero, Carmen; Andrey, Javier; Adame, José Antonio; Sorribas, Mar; Gómez, Laura; Cuevas, Emilio; Gil-Ojeda, Manuel

    2014-10-01

    In the framework of AMISOC (Atmospheric Minor Species relevant to the Ozone Chemistry) project, a multiinstrumented campaign was performed in the Canary Islands area in summer-time from 01 July to 11 August 2013. Both ground-based remote-sensing and airborne in-situ measurements were performed under dust loading conditions. Saharan dusty (DD) conditions were reported during 57% of the overall campaign period. Particular DD cases corresponded to a 2-day period with a progressively arriving Saharan dust intrusion over Tenerife on 31 July (weak incidence) and 01 August (strong incidence). As reference, the non-dusty (ND) situation on 30 July was also examined. Vertical size distributions (SD) for particles within an extended fine-to-coarse (0.16-2.8 ?m) mode were provided by using aircraft aerosol PCASP sonde measurements. Extinction profiles and Lidar ratio (LR) values were derived from Micro Pulse Lidar measurements. Despite no MAXDOAS aerosol profiling retrievals were available, the potential of this technique has also been introduced. A good agreement is found between the optical and microphysical properties, showing dust particles confined in a wide layer of around 4.5 km thickness from 1.5 to 6 km height. Dust incidence mostly affected the Free Troposphere (FT). LR ranged between 50 and 55 sr, showing typical values for Saharan dust particles. In general, the dust impact on mass concentration was enhanced due to the increase of larger particles, affecting both the Boundary layer (BL) and FT, but showing differences depending on the dusty case. MAXDOAS profiles are expected to be included in an extended version of this work.

  10. Effect of particle size on the pore characterization and strength of porous cordierite-mullite ceramics prepared by a pore-forming in-situ technique

    OpenAIRE

    Yan W.; Li N.; Tong J.; Liu G; Xu J

    2013-01-01

    The porous cordierite-mullite ceramics were prepared by the pore-forming in-situ technique. The characterizations of porous cordierite-mullite ceramics were determined by an X-ray diffractometer (XRD), a scanning electron microscopy (SEM), and a microscopy measured method, etc., and the effect of particle size on phase composition, pore characterization and strength were investigated. It’s found that particle size affects strongly the formations of cordierite and mullite, and then cha...

  11. Demonstration of pseudorabies virus DNA in the mouse inner ear by an in situ nucleic acid hybridization technique in plastic embedded bony material

    OpenAIRE

    Falser, N.; Bandtlow, I; Hausmann, M.; Wolf, Hans J.

    1986-01-01

    This investigation is concerned with the possibility of identifying viral DNA using the in situ DNA hybridization method in methylmethacrylate-embedded material. As an experimental model we chose viral labyrinthitis produced by intranasal infection of the mouse with pseudorabies virus. Fixation and embedding methods specially adapted to this procedure and bony histology preparation technique (specimens by grinding or micromilling) made it possible to identify viral DNA directly morphologicall...

  12. A Systematic Review of Biochar Research, with a Focus on Its Stability in situ and Its Promise as a Climate Mitigation Strategy

    Science.gov (United States)

    Gurwick, Noel P.; Moore, Lisa A.; Kelly, Charlene; Elias, Patricia

    2013-01-01

    Background Claims about the environmental benefits of charring biomass and applying the resulting “biochar” to soil are impressive. If true, they could influence land management worldwide. Alleged benefits include increased crop yields, soil fertility, and water-holding capacity; the most widely discussed idea is that applying biochar to soil will mitigate climate change. This claim rests on the assumption that biochar persists for hundreds or thousands of years, thus storing carbon that would otherwise decompose. We conducted a systematic review to quantify research effort directed toward ten aspects of biochar and closely evaluated the literature concerning biochar's stability. Findings We identified 311 peer-reviewed research articles published through 2011. We found very few field studies that addressed biochar's influence on several ecosystem processes: one on soil nutrient loss, one on soil contaminants, six concerning non-CO2 greenhouse gas (GHG) fluxes (some of which fail to support claims that biochar decreases non-CO2 GHG fluxes), and 16–19 on plants and soil properties. Of 74 studies related to biochar stability, transport or fate in soil, only seven estimated biochar decomposition rates in situ, with mean residence times ranging from 8 to almost 4,000 years. Conclusions Our review shows there are not enough data to draw conclusions about how biochar production and application affect whole-system GHG budgets. Wide-ranging estimates of a key variable, biochar stability in situ, likely result from diverse environmental conditions, feedstocks, and study designs. There are even fewer data about the extent to which biochar stimulates decomposition of soil organic matter or affects non-CO2 GHG emissions. Identifying conditions where biochar amendments yield favorable GHG budgets requires a systematic field research program. Finally, evaluating biochar's suitability as a climate mitigation strategy requires comparing its effects with alternative uses of biomass and considering GHG budgets over both long and short time scales. PMID:24098746

  13. Robust Power System Stabilizer Design Using Genetic Local Search Technique for Single Machine Connected to an Infinite Bus

    OpenAIRE

    Mohamed Zellagui

    2008-01-01

    The genetic local search technique hybridizes the genetic algorithm and the local search (such as hill climbing) in order to eliminate the disadvantages in genetic algorithm. The parameters of the power system stabilizer (gain, phase lead time constant) are tuned by considering the single machine connected to infinite bus system. Here, power system stabilizer are used for damping low frequency local mode of oscillations. Eigen value analysis shows that the proposed GLSPSS based PSS have bette...

  14. THE EFFICACY OF REINFORCEMENT TECHNIQUE ON THE FLY ASH STABILIZED EXPANSIVE SOIL AS A SUBGRADE EMBANKMENT FOR HIGHWAYS

    OpenAIRE

    KOTESWARA RAO.D

    2011-01-01

    The most significant factor that influencing the design thickness of a flexible pavement overlay is rebound deformation from repeated load application and subgrade support values . It is essential to stabilize and reinforce the poor soils to bear the traffic intensity or truck loading. Different types of materials are provided with stabilization techniques to achieve suitable performance and to reduce maintenance costs and also to provide required service life for the subgrade embankments. In...

  15. Emulsification technique affects oxidative stability of fish oil-in-water emulsions

    DEFF Research Database (Denmark)

    Horn, Anna Frisenfeldt; Nielsen, Nina Skall

    In oil-in-water emulsions, lipid oxidation is expected to be initiated at the oil-water interface. The properties of the emulsifier used, and the structure at the interface is therefore expected to be of great importance for lipid oxidation in emulsions. Previous studies have shown that e.g. homogenization pressure can affect how proteins locate themselves at the interface of an emulsion. The hypothesis is therefore that emulsions produced with different emulsification equipments differ in their oxidative stability due to differences in the behaviour of the proteins at the interface. The aim of this study was to compare lipid oxidation in 10% fish oil-in-water emulsions prepared by two different kinds of high pressure homogenizers i.e. a microfluidizer and a two valve high pressure homogenizer. Emulsions were made with equal droplet sizes, and with either 1% sodium caseinate or 1% whey protein isolate. Emulsions were characterised and investigated by microscopy. Lipid oxidation was assessed by PV and the formation of secondary volatile oxidation products. Results showed that the different emulsification techniques had an influence on lipid oxidation and that the effect of the emulsification technique depended on the type of protein used as an emulsifier.

  16. Emulsification technique affects oxidative stability of fish oil-in-water emulsion

    DEFF Research Database (Denmark)

    Horn, Anna Frisenfeldt; Nielsen, Nina Skall

    In oil-in-water emulsions, lipid oxidation is expected to be initiated at the oil-water interface. The properties of the emulsifier used, and the structure at the interface is therefore expected to be of great importance for lipid oxidation in emulsions. Previous studies have shown that e.g. homogenization pressure can affect how proteins locate themselves at the interface of an emulsion. The hypothesis is therefore that emulsions produced with different emulsification equipments differ in their oxidative stability due to differences in the behaviour of the proteins at the interface. The aim of this study was therefore to compare lipid oxidation in 10% fish oil-in-water emulsions prepared by two different kinds of high pressure homogenizers i.e. a microfluidizer and a two valve high pressure homogenizer. Emulsions were made with equal droplet sizes, and with either 1% sodium caseinate or 1% whey protein isolate. Emulsions were characterised and investigated by microscopy. Lipid oxidation was assessed by PV and the formation of secondary volatile oxidation products. Results showed that the different emulsification techniques had an influence on lipid oxidation and that the effect of the emulsification technique depended on the type of protein used as an emulsifier.

  17. In Situ Nitroxide-Mediated Polymerized Poly(acrylic acid) as a Stabilizer/Compatibilizer Carbon Nanotube/Polymer Composites

    OpenAIRE

    Laurence Couvreur; Olivier Guerret; Sylvain Bourrigaud; Nicolas Passade-Boupatt; Sylvie Dagréou; Christelle Guerret-Piécourt; Laurent Billon; Vitaliy Datsyuk

    2007-01-01

    Carbon nanotube (CNT) polymer composites were synthesized via in situ nitroxide-mediated diblock copolymerization. Poly(acrylic acid) (PAA) was chosen as a first block to obtain a precomposite CNT-PAA which is readily dispersible in various solvents including water. The immobilization of the stable poly(acrylic acid) alkoxyamine functionality on the nanotube surface occurs during the synthesis of the first block without CNT prior treatment. The living character of this block is established b...

  18. STABILITY OF PATTERNS OF BEHAVIOR IN THE BUTTERFLY TECHNIQUE OF THE ELITE SWIMMERS

    Directory of Open Access Journals (Sweden)

    Hugo Louro

    2010-09-01

    Full Text Available The purpose of this study was to find patterns in the butterfly swimming technique, with an adaptation of the Behavioral Observation System Tech. This, as an instrument for ad-hoc qualitative analysis, enables the study of the stability of the technical implementation. When used in the training of swimmers, analysis can reduce the variability of behavioral tuning swimming technique. Through the analysis of temporal patterns (T-pattern and a sequence of five cycles running at hand maximum speed, the behavior of four technical Portuguese elite swimmers, with a record of 259 alphanumeric codes and a total of 160 configurations, were studied. The structure of the original instrument, based on a mixed system of categories and formats Field, can record technical features, observed during the execution of hand cycles. The validity was ensured through the index of intra-observer reliability (95% and inter-observer accuracy (96%. To detect patterns in each swimmer, the Theme 5.0 software was used, which allowed to identify the stable structures of technical performance within a critical interval of time (p <0.05 - t-patterns. The patterns were different, adjusting to the characteristics of technical implementation of the swimmers. It was found that the swimmer can create settings with different levels of structure complexity, depending on the implementation of changes within the hand cycle. Variations of codes in each configuration obtained using the SOCTM, allowed determining the differences between swimmers. However, the records showed a clear behavioral similarity when comparing the result with a general pattern of the butterfly technique. The potential quality of this instrument seems to be important due to the patterns obtained from a temporal sequence

  19. Report of the first research co-ordination meeting under co-ordinated research project on 'In situ applications of XRF techniques'

    International Nuclear Information System (INIS)

    X-ray fluorescence is a well-established analytical technique widely used in industrial and research applications for materials characterisation. However, a relatively recent development has been the availability of portable instrumentation, which can be used for both the direct in situ non-destructive analysis of samples, and also is readily transportable to field sites for use in a 'mobile laboratory' style of operation. In situ analyses using the XRF technique can make an essential contribution to a wide range of projects, including: - Analysis of soils, particularly in the assessment of agricultural land and contaminated land - Sorting scrap metal alloys and plastics to increase the value of recyclable materials - Geochemical mapping and exploration to locate mineralisation deposits - Environmental monitoring related to air pollution studies and contamination of the work - The on-line control of industrial processes for the production of raw materials - Archaeological studies and the classification of artefacts, the restoration of sculptures, paintings and other objects of cultural heritage. - In situ geochemical studies on Mars, including the 1997 NASA Pathfinder mission and the forthcoming European Space Agency Mars Express mission, which includes the In these applications, the major advantages of field-portable X-ray fluorescence (FPXRF) spectrometry include: on-site immediate availability of analytical results, non-destructive analysis, a multielement capability, speed of operation and access to valuable/unique samples that otherwise would be unavailable for chemical analysis. The CRP on 'In situ applications of XRF techniques' is one element of the project on Nuclear Instruments for Specific Applications the major objective of which is to assist Member States in the development of nuclear instruments and software for special applications, such as the characterisation of materials. An overall objective of this CRP is to assist laboratories in Member States in such areas as environmental pollution monitoring, mineral exploration, the preservation of cultural heritage, the control of industrial processes and the optimisation of analytical methodologies for these applications using FPXRF

  20. Thermal stability and long term hydrogen/deuterium release from soft to hard amorphous carbon layers analyzed using in-situ Raman spectroscopy. Comparison with Tore Supra deposits

    CERN Document Server

    Pardanaud, C; Giacometti, G; Mellet, N; Pégourié, B; Roubin, P

    2015-01-01

    The thermal stability of 200 nm thick plasma enhanced chemical vapor deposited a-C:H and a-C:D layers ranging from soft to hard layers has been studied and compared to that of deposits collected on the Tore Supra tokamak plasma facing components by means of in-situ Raman spectroscopy. Linear ramp heating and long term isotherms (from several minutes to 21 days) have been performed and correlations between spectrometric parameters have been found. The information obtained on the sp 2 clustering has been investigated by comparing the G band shift and the 514 nm photon absorption evolution due to the thermal treatment of the layer. The effects of isotopic substitution have also been investigated.

  1. Stability of Patterns of Behavior in the Butterfly Technique of the Elite Swimmers

    Science.gov (United States)

    Louro, Hugo; Silva, António J.; Anguera, Teresa; Marinho, Daniel A.; Oliveira, Conceição; Conceição, Ana; Campaniço, Jorge

    2010-01-01

    The purpose of this study was to find patterns in the butterfly swimming technique, with an adaptation of the Behavioral Observation System Tech. This, as an instrument for ad-hoc qualitative analysis, enables the study of the stability of the technical implementation. When used in the training of swimmers, analysis can reduce the variability of behavioral tuning swimming technique. Through the analysis of temporal patterns (T-pattern) and a sequence of five cycles running at hand maximum speed, the behavior of four technical Portuguese elite swimmers, with a record of 259 alphanumeric codes and a total of 160 configurations, were studied. The structure of the original instrument, based on a mixed system of categories and formats Field, can record technical features, observed during the execution of hand cycles. The validity was ensured through the index of intra-observer reliability (95%) and inter-observer accuracy (96%). To detect patterns in each swimmer, the Theme 5.0 software was used, which allowed to identify the stable structures of technical performance within a critical interval of time (p <0.05) - t-patterns. The patterns were different, adjusting to the characteristics of technical implementation of the swimmers. It was found that the swimmer can create settings with different levels of structure complexity, depending on the implementation of changes within the hand cycle. Variations of codes in each configuration obtained using the SOCTM, allowed determining the differences between swimmers. However, the records showed a clear behavioral similarity when comparing the result with a general pattern of the butterfly technique. The potential quality of this instrument seems to be important due to the patterns obtained from a temporal sequence. Key points The patterns were different, adjusting to the characteristics of technical implementation of the swimmers. The swimmer can make settings with different levels of structure complexity, depending on the implementation of changes within the hand cycle. Variations of codes in each configuration obtained using the SOCTM, allowed determining the differences between swimmers. The records showed a clear behavioral similarity when comparing the result with a general pattern of the butterfly technique. The potential quality of this instrument seems to be important due to the patterns obtained from a temporal sequence. PMID:24149384

  2. In-Situ Uranium Stabilization Through Polyphosphate Injection: Pilot-Scale Treatability Test at the 300 Area, Hanford Site - 8187

    International Nuclear Information System (INIS)

    This paper describes the pilot-scale treatability test that was conducted to evaluate the efficacy of using a polyphosphate injection approach to treat uranium-contaminated groundwater in situ within the 300 Area aquifer at the Hanford Site in Richland, Washington. Primary test objectives were to assess (1) direct treatment of available uranium contributing to the groundwater plume through precipitation of the uranyl phosphate mineral autunite, and (2) emplacement of secondary-treatment capacity via precipitation of the calcium phosphate mineral apatite, which acts as a long-term sorbent for uranium

  3. Synthesis of 1,1-disubstituted tetrahydroisoquinolines by lithiation and substitution, with in situ IR spectroscopy and configurational stability studies.

    Science.gov (United States)

    Li, Xiabing; Coldham, Iain

    2014-04-16

    Lithiation of N-Boc-1-phenyltetrahydroisoquinolines was optimized by in situ IR spectroscopy. The kinetics for rotation of the carbamate group and for the enantiomerization of the organolithium were determined. The organolithium is configurationally stable at low temperature, and the asymmetric synthesis of 1,1-disubstituted tetrahydroisoquinolines can be achieved with high yields and high enantiomer ratios. The chemistry was applied to the preparation of FR115427 and provides a way to recycle the undesired enantiomer in the synthesis of solifenacin. PMID:24707968

  4. Aqueous Foams Stabilized by Hydrophilic Silica Nanoparticles via In-Situ Physisorption of Nonionic TX100 Surfactant

    Directory of Open Access Journals (Sweden)

    Suriatie Yusuf

    2013-01-01

    Full Text Available This paper present the study of aqueous CO foam prepared 2 by a mixtures hydrophilic silica nanoparticles and non-ionic Triton X100, TX100, surfactant. The synergistic effects of the mixture on stabilizing the CO2 foam were inferred into few key parameters namely; particles and surfactant concentration, adsorption of surfactant onto the particles via surface tension and adsorption isotherm, foam lifetime and, the size of the bubbles produced. It was found that the adsorption behaviour of TX100 on silica surface exhibit a particular characteristics depend on the concentration of silica, high total surface area available leads to high adsorptionof surfactant molecules. The synergetic performance of silica/TX100 in stabilizing foam can be observed at low (0.01% and intermediate (0.1% concentration of TX100. Lower concentration required low silica concentration while the intermediate concentration required high silica fraction in the dispersion to stabilize the foam.

  5. Predicting the stability of horizontal wells and multi-laterals - the role of in situ stress and rock properties

    Energy Technology Data Exchange (ETDEWEB)

    Moos, A.; Peska, P. [GeoMechanics International (United States); Zoback, M. D. [Stanford Univ., CA (United States)

    1998-12-31

    A new suite of software tools, developed to study wellbore stability in a wide variety of geologic environments is introduced as means by which to accurately predict optimally-stable wellbore trajectories from knowledge of the stress tensor. In step one of the process stress, is determined from observations of failure in existing wells; in step two, this knowledge is applied to predict the stability of proposed wells while drilling, as well as later during production. Three case studies are presented to illustrate use of this approach. The examples concentrate on issues related to the stability of highly inclined wells, but the approach can be used to determine the state of stress for other purposes as well. 21 refs., 8 figs.

  6. Biodegradable surfactant stabilized nanoscale zero-valent iron for in situ treatment of vinyl chloride and 1,2-dichloroethane

    International Nuclear Information System (INIS)

    Highlights: ? Biodegradable surfactant stabilized nanoscale zero-valent iron (NZVI) is tested. ? Vinyl chloride and 1,2-dichloroethane are remediated by NZVI in the field. ? Multiple functions of biodegradable surfactants are confirmed. ? Biodegradable surfactants stabilize NZVI and facilitate the bioremediation. ? NZVI creates reducing conditions beneficial to an anaerobic bioremediation. - Abstract: Nanoscale zero-valent iron (NZVI) stabilized with dispersants is a promising technology for the remediation of contaminated groundwater. In this study, we demonstrated the use of biodegradable surfactant stabilized NZVI slurry for successful treatment of vinyl chloride (VC) and 1,2-dichloroethane (1,2-DCA) in a contaminated site in Taiwan. The biodegradable surfactant stabilized NZVI was coated with palladium and synthesized on-site. From monitoring the iron concentration breakthrough and distribution, it was found that the stabilized NZVI is capable of transporting in the aquifer at the test plot (200 m2). VC was effectively degraded by NZVI while the 1,2-DCA degradation was relatively sluggish during the 3-month field test. Nevertheless, as 1,2-DCA is known to resist abiotic reduction by NZVI, the observation of 1,2-DCA degradation and hydrocarbon production suggested a bioremediation took place. ORP and pH results revealed that a reducing condition was achieved at the testing area facilitating the biodegradation of chlorinated organic hydrocarbonschlorinated organic hydrocarbons. The bioremediation may be attributed to the production of hydrogen gas as electron donor from the corrosion of NZVI in the presence of water or the added biodegradable surfactant serving as the carbon source as well as electron donor to stimulate microbial growth.

  7. Demonstration of pseudorabies virus DNA in the mouse inner ear by an in situ nucleic acid hybridization technique in plastic embedded bony material.

    Science.gov (United States)

    Falser, N; Bandtlow, I; Haus, M; Wolf, H

    1986-01-01

    This investigation is concerned with the possibility of identifying viral DNA using the in situ DNA hybridization method in methylmethacrylate-embedded material. As an experimental model we chose viral labyrinthitis produced by intranasal infection of the mouse with pseudorabies virus. Fixation and embedding methods specially adapted to this procedure and bony histology preparation technique (specimens by grinding or micromilling) made it possible to identify viral DNA directly morphologically and virologically in the inner ear. Quantitative microphotometric analyses of trans-sagittal sections of the entire skull after in situ DNA hybridization are presented and discussed here as an explicit method of investigating the path of distribution of viral DNA in the brain and the inner ear. PMID:3007764

  8. In situ TEM observation of synergistic electronic-excitation-effects of phase stability in III-V binary compound nanoparticles

    Science.gov (United States)

    Yasuda, H.; Tanaka, A.; Usui, H.; Mori, H.; Lee, J. G.

    2007-07-01

    Electronic-excitation-effects of phase stability in III-V binary compound nanoparticles have been studied by TEM. When GaSb particles were excited by 75 keV electrons, the compound transforms to a two-phase consisting of an antimony core and a gallium shell or an amorphous phase, or remains the original crystalline phase, depending on particle size and/or temperature. It is suggested that such nonlinear responses of the phase stability may arise from synergistic effects of bond instability under excited states, formation of high density of excited states, chemical equilibrium under excited states and temperature dependence of defects mobility.

  9. A comparison of the mechanical stability of silicon nitride films deposited with various techniques

    International Nuclear Information System (INIS)

    Highlights: ? LPCVD, RTCVD and ALD as-deposited nitride films present tensile stress dependant on the Si/N ratio and are thermally stable. ? Stress of as-deposited PECVD nitride layers range from compressive to tensile, depending on ion bombardment during growth. ? After high temperature annealing, PECVD nitride films behave similarly to LPCVD layers. ? Young's moduli and density are positively correlated. - Abstract: A comparison of mechanical properties of amorphous silicon nitride thin films deposited with various techniques used for microelectronic applications was conducted. Nitride films with thicknesses less than 80 nm were deposited on (0 0 1) oriented silicon wafers by using various methods: low pressure chemical vapor deposition (LPCVD), rapid thermal CVD (RTCVD), atomic layer deposition (ALD) and plasma enhanced CVD (PECVD). The wafer curvature method was used to show that the as-deposited LPCVD, RTCVD and ALD films exhibited tensile residual stresses that decreased with silicon richness. In contrast, the stress of the PECVD as-deposited layers ranged from tensile to ultra-compressive, depending on the exposure to high plasma power and ion bombardment during growth. After high temperature annealing, the LPCVD, RTCVD and ALD nitride stresses were almost unchanged, indicating that these films/substrate systems have significant thermal mechanical stability. In contrast, it was observed that, regardless of the initial stress, the annealed PECVD films detress, the annealed PECVD films developed tensile stress after high temperature treatment, with the same dependence of stress on refractive index as was found with the other deposition techniques. The Young's moduli, measured by performing nano-indentation on 200 nm thick nitride layers, were found for most samples to be correlated with film density.

  10. Importance of shale anisotropy in estimating in-situ stresses and wellbore stability analysis in Horn River basin

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Safdar; Ansari, Sajjad; Han, Hongxue; Khosravi, Nader [Schlumberger (United States)

    2011-07-01

    The importance of understanding shale formation anisotropic behavior prior to drilling was discussed in this paper. The objective of this work is to show how shale anisotropy is often not taken into consideration in conventional wellbore analysis, and how this practice might lead to serious consequences and instabilities in the wellbore system. Two fields in the Horn River basin area were investigated. The laminated structures of the shale were explained and the mechanical properties including in-situ stresses, directional variations, and horizontal and vertical Young's modulus were calculated. In general the investigated region proved to be highly anisotropic. It was proposed that this phenomenon was the main reason for discrepancies in mechanical properties along the parallel and perpendicular directions of the planes. Moreover, it was shown that not taking anisotropic effects into consideration can cause miscalculations of in-situ stresses and breakdown pressure; hence, causing instabilities in the wellbore system. Therefore, anisotropic analysis was recommended as an important step in designing wells.

  11. Engineered In-Situ Precipitation of Technetium and Uranium in Groundwater at the Savannah River Site: Treatment Targeting Long-Term Stability (Invited)

    Science.gov (United States)

    Gillow, J. B.; Lutes, C. C.; Frizzell, A.; Clark, B.; Horst, J.

    2009-12-01

    The U.S. Department of Energy (DOE) Savannah River Site (SRS) is a former nuclear weapons facility that is undergoing clean-up of groundwater and soil contamination. Alternatives to conventional pump-and-treat are being evaluated through DOE’s Advanced Remediation Technologies (ART) program as part of the EM-22 Groundwater and Soil Remediation program. A pilot project is underway to evaluate an emerging approach to remediation through the in-situ precipitation of insoluble forms of technetium and uranium. The demonstration involves the injection of organic carbon into the aquifer to stimulate biogeochemical processes leading to the transformation of soluble radionuclides to insoluble forms. However, once carbon addition is ceased and geochemical conditions return to oxidizing, the insoluble radionuclides may re-dissolve. The pilot project will target long term stability by enhancing the creation of reduced mineral forms in and around the precipitated radionuclides to act as both a redox buffer for oxidizing groundwater and as a sorptive medium for any dissolved uranium and technetium. Successful treatment with respect to in situ radionuclide precipitation extends beyond numeric cleanup goals and invokes a standard of care that considers not only short-term solubility achieved during active remediation, but the range of factors that might erode/compromise the stability of the precipitated solids over the long-term. Long-term stability may be achieved by incorporating the targeted radionuclide in a matrix of other precipitates formed through the treatment process. In the short term, this can include the precipitates of other more abundant metals (e.g., iron) that can preferentially scavenge oxygen. Longer term, this is expected to transition to passivation within a matrix of more stable mineral phases, such that rates of rebound dissolution are sufficiently suppressed to maintain dissolved concentrations below remedial targets. The in situ reactive zone (IRZ) treatment will be sustained for 2 years, followed by a period of rebound monitoring to determine the stability of the insoluble metals and radionuclides. The treatment will promote microbial sulfate-reducing conditions in order to facilitate uranium precipitation as well as formation of sparingly soluble technetium phases incorporated into iron sulfide and other biogenic iron minerals. A key to sustained treatment is the establishment of a mass of minerals within the treatment zone capable of consuming incoming oxidants (present in the naturally oxic aquifer) as well as the creation of sorptive mineral phases for long-term stabilization. Soil samples were obtained during well installation for geochemical, radiological, and mineralogical analysis to establish the baseline conditions; the biogenic mineral matrix will be characterized in the post-treatment soil samples. A key aspect for achieving optimum treatment is through initial tracer testing, which is being used to refine substrate distribution strategy. The treatment pilot will be discussed in the context of this strategy.

  12. Study of thermal stability of ZnO:B films grown by LPCVD technique

    International Nuclear Information System (INIS)

    Zinc oxide thin films with different boron doping levels (ZnO:B) are prepared by low pressure chemical vapor deposition (LPCVD) technique. All films here exhibit a pyramid-like surface texture. Stability of the ZnO:B films is systematically investigated through a post heat treatment at ambient temperatures of 300 °C and 250 °C for different durations. It is found that total transmission (TT) of these films at near infrared (NIR) wavelength range increases with the enhanced thermal treating intensity, which could be attributed to decrease of free carrier concentration inside the films. Moreover, light absorption in NIR wavelength range decreases profoundly with the increasing carrier concentration after a post thermal treatment in particular for highly doped ZnO:B films. However, morphology of these ZnO:B films does not vary after the thermal treatment and thus the corresponding light scattering properties do not change as well. Therefore, the thermally treated ZnO:B films may lead to an increase in light-generated current and resulting a higher cell efficiency due to the enhancement of TT when they work as front contact in silicon thin film solar cells.

  13. Real-time in situ measurements of trace gases from agriculturally cultivated soils by means of laser spectroscopic techniques

    OpenAIRE

    Hillebrand, Malte

    2008-01-01

    Zwei Messgeräte, zur Untersuchung des klimarelevanten Treibhausgasaustauschs zwischen landwirtschaftlich genutzten Böden und der Atmosphäre in der Nordchinesischen Tiefebene, werden in dieser Arbeit präsentiert. Sie basieren auf dem Prinzip der photoakustischen Spektroskopie mithilfe von Diodenlasern (Tunable Diode Laser Photoacoustic Spectroscopy, TDL-PAS). Die Geräte sind für in situ Echtzeitmessungen von Spurengasen geeignet. Nachweisgrenzen bei Methan von 85 ppb und bei Ammoniak von...

  14. Dynamic Clustering with Relay Nodes (DCRN: A Clustering Technique to Maximize Stability in Wireless Sensor Networks with Relay Nodes

    Directory of Open Access Journals (Sweden)

    Vijay Raghunathan

    2012-06-01

    Full Text Available With the growing popularity of wireless sensor networks, network stability has become a key area of current research. Different applications of wireless sensor networks demand stable sensing, coverage, and connectivity throughout their operational periods. In some cases, the death of just a single sensor node might disrupt the stability of the entire network. Therefore, a number of techniques have been proposed to improve the network stability. Clustering is one of the most commonly used techniques in this regard. Most clustering techniques assume the presence of high power sensor nodes called relay nodes and implicitly assume that these relay nodes serve as cluster heads in the network. This assumption may lead to faulty network behavior when any of the relay nodes becomes unavailable to its followers. Moreover, relay node based clustering techniques do not address the heterogeneity of sensor nodes in terms of their residual energies, which frequently occur during the operation of a network. To address these two issues, we present a novel clustering technique, Dynamic Clustering with Relay Nodes (DCRN, by considering the heterogeneity in residual battery capacity and by removing the assumption that relay nodes always serve as cluster-heads. We use an essence of the underlying mechanism of LEACH (Low-Energy Adaptive Clustering Hierarchy, which is one of the most popular clustering solutions for wireless sensor networks. In our work, we present four heuristics to increase network stability periods in terms of the time elapsed before the death of the first node in the network. Based on the proposed heuristics, we devise an algorithm for DCRN and formulate a mathematical model for its long-term rate of energy consumption. Further, we calculate the optimal percentage of relay nodes from our mathematical model. Finally, we verify the efficiency of DCRN and correctness of the mathematical model by exhaustive simulation results. Our simulation results reveal that DCRN enhances the network stability period by a significant margin in comparison to LEACH and its best-known variant.

  15. Stability-enhanced indium hexacyanoferrate electrodes: Morphological characterization, in situ EQCM analysis in nonaqueous electrolytes and application to a WO3 electrochromic device

    International Nuclear Information System (INIS)

    This paper presents a promising transparent counterelectrode system for a WO3 electrochromic device (ECD) on the basis of a stability-enhanced indium hexacyanoferrate (InHCF) electrode and a NaClO4/propylene carbonate (PC) electrolyte. Through SEM characterization it was found that clusters of granular InHCF nanoparticles (ca. 80-140 nm) were deposited on ITO substrates in HCl and KCl-stabilized plating solutions, and uniform micrometer thick films with high charge capacity could be obtained. From in situ electrochemical quartz crystal microbalance study, it was discovered that Na+ would enter or move out from the InHCF film in the 'desolvated' form during the redox process in a PC electrolyte. Besides, NaClO4/PC resulted in higher electrochemical activity and reversibility than LiClO4/PC. With these discoveries, a durable WO3-InHCF ECD featuring blue-to-colorless electrochromism was fabricated successfully. The device remained 73.6 and 88.7% of its initial ?T values at 600 and 800 nm after 40,000 rapid and successive coloring/bleaching cycles, respectively. Moreover, the cycling-induced loss of electrochromic performance almost completely restored after 1-month rest and kept unchanged for another month. Thus, the applicability of this nonaqueous InHCF counterelectrode system to ECDs was verified

  16. Thermal stability and kinetic study of poly(ethyl methacrylate-co-acrylonitrile) nanocomposites prepared by in situ polymerization in presence of an Algerian bentonite

    Energy Technology Data Exchange (ETDEWEB)

    Kadi, Souad [Université des Sciences et de la Technologie Houari Boumediene, Laboratoire des Matériaux Polymères, Faculté de Chimie, BP 32 El-Alia, Bab-Ezzouar, 16111 Algiers (Algeria); Djadoun, Saïd, E-mail: matpolylab@yahoo.fr [Université des Sciences et de la Technologie Houari Boumediene, Laboratoire des Matériaux Polymères, Faculté de Chimie, BP 32 El-Alia, Bab-Ezzouar, 16111 Algiers (Algeria); Sbirrazzuoli, Nicolas [Univ. Nice Sophia Antipolis, CNRS, LPMC, UMR 7336, 06100 Nice (France)

    2013-10-10

    Graphical abstract: - Highlights: • poly(ethyl methacrylate-co-acrylonitrile) nanocomposites were successfully prepared. • These nanocomposites were of higher T{sub g} and improved thermal stability. • Their (E{sub ?}) of thermal decomposition were higher than those of the virgin copolymer. • Increase of (E{sub ?}), confirmed change in the degradation mechanism with clay loading. - Abstract: Poly(ethyl methacrylate-co-acrylonitrile) (PEAMN20) nanocomposites were successfully prepared via free radical in situ polymerization using a bentonite from Algeria modified by Hexadecyltrimethylammonium chloride (HDTMA). X-ray diffraction (XRD) and transmission electronic microscopy (TEM) investigations revealed that depending on the OMMT loading, intercalated or partially exfoliated nanocomposites were obtained. These nanocomposites exhibited an overall improved thermal stability and an increase in their glass transition temperature compared to the pure copolymer (PEMAN20) as evidenced by Thermogravimetric (TGA) and Differential Scanning Calorimetry (DSC) analysis. Apparent activation energies (E{sub ?}) of thermal decomposition of the elaborated nanocomposites, determined by Tang method, were higher than those of the virgin copolymer. The significant increase of (E{sub ?}), observed with PEMAN20/OMMT (1 wt%) confirmed the change in the degradation mechanism with OMMT loading and the ratio of intercalated/exfoliated structures.

  17. Thermal stability and kinetic study of poly(ethyl methacrylate-co-acrylonitrile) nanocomposites prepared by in situ polymerization in presence of an Algerian bentonite

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • poly(ethyl methacrylate-co-acrylonitrile) nanocomposites were successfully prepared. • These nanocomposites were of higher Tg and improved thermal stability. • Their (E?) of thermal decomposition were higher than those of the virgin copolymer. • Increase of (E?), confirmed change in the degradation mechanism with clay loading. - Abstract: Poly(ethyl methacrylate-co-acrylonitrile) (PEAMN20) nanocomposites were successfully prepared via free radical in situ polymerization using a bentonite from Algeria modified by Hexadecyltrimethylammonium chloride (HDTMA). X-ray diffraction (XRD) and transmission electronic microscopy (TEM) investigations revealed that depending on the OMMT loading, intercalated or partially exfoliated nanocomposites were obtained. These nanocomposites exhibited an overall improved thermal stability and an increase in their glass transition temperature compared to the pure copolymer (PEMAN20) as evidenced by Thermogravimetric (TGA) and Differential Scanning Calorimetry (DSC) analysis. Apparent activation energies (E?) of thermal decomposition of the elaborated nanocomposites, determined by Tang method, were higher than those of the virgin copolymer. The significant increase of (E?), observed with PEMAN20/OMMT (1 wt%) confirmed the change in the degradation mechanism with OMMT loading and the ratio of intercalated/exfoliated structures

  18. The application of fluorescence in situ hybridization (FISH technique for studying the microbial communities in intestinal tissues of white shrimp (Penaeus vannamei

    Directory of Open Access Journals (Sweden)

    Supamattaya, K.

    2005-02-01

    Full Text Available Fluorescence in situ hybridization technique is very useful for the evaluation of microbial communities in various environments. It is possible to apply this technique to study the intestinal microflora in white shrimp (Penaeus vannamei. Different fixatives and storage temperature were tested in this technique. It was found that fixation with 10% buffered formalin for 12 hours and changed to 70% ethanol shown positive results when compared to the fixation with Davidson's fixative or RF fixative. The best signaling was obtainedfrom the samples which were stored in -20ºC. By using the DNA probe targeted to the Eubacteria domain (EUB338 probe, 5?-GCT GCC TCC CGT AGG AGT-3? labeled with fluorescein as a hybridizing probe, it was found that most intestinal microflora were aggregated with the intestinal contents, or dispersed in the lumen. There was not evidence of the attachment of the microflora with the intestinal epithelium in this study.

  19. Investigations on dry sliding wear behavior of in situ casted AA7075–TiC metal matrix composites by using Taguchi technique

    International Nuclear Information System (INIS)

    Highlights: • The AA7075–TiC metal matrix composites were produced by in situ casting technique. • The produced composites were characterized by XRD analysis and SEM. • The dry sliding wear behavior of composites was investigated by Taguchi technique. • The significant factors and their contribution in wear rate identified by ANOVA. • The formation of oxidation at high sliding velocity was verified by EDS. - Abstract: High strength 7075 aluminum matrix composites with 4 and 8 wt.% of TiC particulate reinforcement was synthesized by reactive in situ casting technique. X-ray diffraction analysis and scanning electron microscopy were used to confirm the presence of TiC particles and its uniform distribution over the aluminum matrix. The dry sliding wear behavior of the as-casted composites was investigated based on Taguchi L27 orthogonal array experimental design to examine the significance of reinforcement quantity, load, sliding velocity and sliding distance on wear rate. The combination of 4 wt.% of TiC, 9.81 N load, 3 m/s sliding velocity and 1500 m sliding distance was identified as the optimum blend for minimum wear rate using the main effect plot. Load and sliding velocity were identified as the highly contributing significant parameters on the wear rate using ANOVA analysis. Further a confirmation test was also conducted with the optimum parameter combination for validation of the Taguchi results

  20. Study of phase stability in a class of binary alloys using augmented space recursion based orbital peeling technique

    International Nuclear Information System (INIS)

    In this communication we have developed a recursion based approach to the study of phase stability and transition of binary alloys. We have combined the recursion method introduced by Haydock et al. [J. Phys. C: Solid State Phys. 5 (1972) 2845] and the our augmented space approach [A. Mookerjee, J. Phys. C: Solid State Phys. 6 (1973) 1340] with the orbital peeling technique proposed by Burke [Surf. Sci. 58 (1976) 349] to determine the small energy differences involved in the discussion of phase stability. We have studied three alloy systems: one which segregates and the other two orders at lower temperatures

  1. Determination of stability constants of iron(III and chromium(III-nitrilotriacetate-methyl cysteine mixed complexes by electrophoretic technique

    Directory of Open Access Journals (Sweden)

    Brij Bhushan Tewari

    2004-06-01

    Full Text Available The stability constants of Fe(III and Cr(III with methyl cysteine and nitrilotriacetate (NTA were determined by paper electrophoretic technique. Beside binary ternary complexes have also been studied, in which nitrilotriacetate and methyl cysteine acts as primary and secondary ligand, respectively. The stability constants of mixed ligand complexes metal (M-nitrilotriacetate-methyl cysteine have been found to be 5.72 plus or minus 0.09 and 5.54 plus or minus 0.11 (log K values for Fe(III and Cr(III complexes, respectively, at 35 oC and ionic strength 0.1 M.

  2. The influence of additives on the morphology and stability of roll-to-roll processed polymer solar cells studied through ex situ and in situ X-ray scattering

    DEFF Research Database (Denmark)

    Zawacka, Natalia Klaudia; Andersen, Thomas Rieks

    2014-01-01

    The effect of twelve different additives on organic solar cells with an active layer based on poly-3- hexylthiophene (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) has been studied in this work and tested for suitability in roll-to-roll slot-die coating. Three of the twelve additives increased the solar cell efficiency while the rest showed no effect or a negative influence on the efficiency and coatability. In cases where the additive caused an increase in performance the relation to surface topography and the structure was investigated using Atomic Force Microscopy (AFM), UV-Vis Spectroscopy and Small Angle X-ray Scattering (SAXS) for cells prepared with 1-chloronaphthalene (CN), N-methyl-2-pyrrolidone (NMP) and 1,3-dimethyl-barbituric acid (BARB) as processing additives. The studies suggested that the use of these additives resulted in films with improved morphology and electrical properties of the active layer. The effect of the CN on structural evolution during different solvent evaporation and annealing times was further investigated with an in situ roll-to-roll X-ray study. Lifetime studies under continuous illumination were used to assess the impact of the additives on the stability of the prepared devices that had an active area of 1 cm2.

  3. Combination of Fluorescence In Situ Hybridization with Staining Techniques for Cell Viability and Accumulation of PHA and polyP in Microorganisms in Complex Microbial Systems

    Science.gov (United States)

    Nielsen, Jeppe Lund; Kragelund, Caroline; Nielsen, Per Halkjær

    Fluorescence in situ hybridization (FISH) can be combined with a number of staining techniques to reveal the relationships between the microorganisms and their function in complex microbial systems with a single-cell resolution. In this chapter, we have focused on staining methods for intracellular storage compounds (polyhydroxyalkanoates, polyphosphate) and a measure for cell viability, reduction of the tetrazolium-based redox stain CTC. These protocols are optimized for the study of microorganisms in waste-water treatment (activated sludge and biofilms), but they may also be used with minor modifications in many other ecosystems.

  4. A study on the annealing behavior of Cu-added bake-hardenable steel using an in situ EBSD technique

    International Nuclear Information System (INIS)

    A combination of electron backscatter diffraction and in situ heating was used to study the annealing behavior of Cu-added bake-hardenable (BH) steel. The annealing behavior of cold-rolled, Cu-added BH steel was strongly dependent on the type and number of average orientations developed in the deformed grains. If deformed grains (type I) had a single ?-fiber component as the average orientation of a unique grain (UG), the density of the nuclei was very low and recrystallization began at a later stage of the in situ annealing. However, the average grain size of the recrystallized grains was drastically increased regardless of the deformed grain as soon as recrystallization had begun. If deformed grains (type II) had multiple ?-fiber components as the average orientation of a UG, the density of the nuclei steadily increased as the elapsed time of in situ annealing increased. The area fraction of the recrystallized grains in the partially recrystallized specimens gradually increased, but the kinetics depended on the deformed matrix. However, the average grain size of the recrystallized grains gradually increased in all deformed grains from the beginning of in situ annealing. If deformed grains (type III) had texture components which could not be assigned to either ?-fiber or ?-fiber components as the average orientation of a UG, the number of the recrystallized grains was maximized, but the recrystallization kinetics based on a normalized number of recrystallized grains was similar to that of type II. Since type III was a minor deformed grain in the as-rolled Cu-added BH steel, the recrystallization in types I and II was identified as the principal feature determining the overall recrystallization phenomena of Cu-added BH steel

  5. A Localized In-Situ Hydrogel-Mediated Protein Digestion and Extraction Technique For On-Tissue Analysis

    OpenAIRE

    Harris, Glenn A.; Nicklay, Joshua J.; Caprioli, Richard M.

    2013-01-01

    A simultaneous on-tissue proteolytic digestion and extraction method is described for the in-situ analysis of proteins from spatially distinct areas of a tissue section. The digestion occurs on-tissue within a hydrogel network, and peptides extracted from this gel are identified with liquid chromatography tandem MS (LC-MS/MS). The hydrogels are compatible with solubility agents (e.g. chaotropes and detergents) known to improve enzymatic digestion of proteins. Additionally, digestions and extr...

  6. Determination Nutritional Value and Digestibility of Three Rangeland Plants of through Chemical Method and in Situ (Nylon Bags Techniques

    Directory of Open Access Journals (Sweden)

    Ali Ahmad Ghotbi

    2012-04-01

    Full Text Available This research has been conducted to evaluate nutritional value, digestibility and degradability of three rangeland species Dactylic glomereta, Onobrychis sativa and Setaria galauca through chemical and in situ methods. The experiment conducted based on Randomized Complete Design with three fistulated sheep in 3 replications and obtained data were analyzed by software SAS and Neway. Specifications such as Crude Protein (CP, Neutral Detergent Fiber (NDF, Acid Detergent Fiber (ADF, Ether Extract (EE, Ash, Crude Fiber (CF, NFC (Non Fiber Carbohydrate, Nitrogen Free Extract (NFE and organic material (OM were determined in chemical method and degradation of dry matter and protein were determined at times 0, 4, 8, 16, 24, 48, 72 and 96 through in situ method for the three species. O. sativa showed the most amount of crude protein (23.95% and the least amount of ADF. Also, S. galauca showed the least amount of protein (7.95% and the most amount of ADF (45.73%. Results of degradability in in-situ (nylon bags method show that S. galauca has the least and O. sativa has the most degradability of dry matter and protein. Results also show that O. sativa and D. glomereta have the capability of being applied as livestock food and S. galauca could be applied aslivestock food in combination with suitable species of legumes.

  7. THERMAL TECHNIQUES FOR THE IN-SITU CHARACTERIZATION AND REMEDIATION OF MERCURY: INSIGHTS FROM DEPLOYMENT OF THE MEMBRANE INTERFACE PROBE

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Dennis; Looney, Brian; Eddy-Dilek, Carol A.

    2013-08-07

    This presentation focuses on how thermal energy can effectively be used to enhance characterization, promote the remediation, and aid in delivering a sequestering agent to stabilize elemental mercury in subsurface soils. Slides and speaker notes are provided.

  8. The search for stability: bar displacement in three series of pectus excavatum patients treated with the Nuss technique

    Directory of Open Access Journals (Sweden)

    Miguel Lia Tedde

    2011-01-01

    Full Text Available OBJECTIVES: To compare bar displacement and complication rates in three retrospective series of patients operated on by the same surgical team. METHOD: A retrospective medical chart analysis of the three patient series was performed. In the first series, the original, unmodified Nuss technique was performed. In the second, we used the ''third point fixation'' technique,and in the last series, the correction was performed with modifications to the stabilizer and stabilizer position. RESULTS: There were no deaths in any of the series. Minor complications occurred in six (4.9% patients: pneumothorax with spontaneous resolution (2, suture site infection (2, and bar displacement without the reoperation need (2. Major complications were observed in eight (6.5% patients: pleural effusion requiring drainage (1, foreign body reaction to the bar (1, pneumonia and shock septic (1, cardiac perforation (1, skin erosion/seroma (1, and displacement that necessitated a second operation to remove the bar within the 30 days of implantation (3. All major complications occurred in the first and second series. CONCLUSION: The elimination of fixation wires, the use of shorter bars and redesigned stabilizers placed in a more medial position results in a better outcome for pectus excavatum patients treated with the Nuss technique. With bar displacement and instability no longer significant postoperative risks, the Nuss technique should be considered among the available options for the surgical correction of pectus excavatum in pediatric patients.

  9. The search for stability: bar displacement in three series of pectus excavatum patients treated with the Nuss technique

    Scientific Electronic Library Online (English)

    Miguel Lia, Tedde; Jose Ribas Milanez de, Campos; João-Carlos, Das-Neves-Pereira; Fernando Conrado, Abrao; Fábio Biscegli, Jatene.

    1743-17-01

    Full Text Available OBJECTIVES: To compare bar displacement and complication rates in three retrospective series of patients operated on by the same surgical team. METHOD: A retrospective medical chart analysis of the three patient series was performed. In the first series, the original, unmodified Nuss technique was p [...] erformed. In the second, we used the ''third point fixation'' technique,and in the last series, the correction was performed with modifications to the stabilizer and stabilizer position. RESULTS: There were no deaths in any of the series. Minor complications occurred in six (4.9%) patients: pneumothorax with spontaneous resolution (2), suture site infection (2), and bar displacement without the reoperation need (2). Major complications were observed in eight (6.5%) patients: pleural effusion requiring drainage (1), foreign body reaction to the bar (1), pneumonia and shock septic (1), cardiac perforation (1), skin erosion/seroma (1), and displacement that necessitated a second operation to remove the bar within the 30 days of implantation (3). All major complications occurred in the first and second series. CONCLUSION: The elimination of fixation wires, the use of shorter bars and redesigned stabilizers placed in a more medial position results in a better outcome for pectus excavatum patients treated with the Nuss technique. With bar displacement and instability no longer significant postoperative risks, the Nuss technique should be considered among the available options for the surgical correction of pectus excavatum in pediatric patients.

  10. Comparative stability analyses of traditional and selective room-and-pillar mining techniques for sub-horizontal tungsten veins

    Science.gov (United States)

    Navarro Torres, Vidal Félix; Dinis da Gama, Carlos; Costa E Silva, Matilde; Neves, Paula Falcão; Xie, Qiang

    2011-02-01

    The stability and productivity concerning a modification on the traditional room and pillar for a new selective technique at the Portuguese Panasqueira Mine have been described. The traditional room-and-pillar stoping uses 5.0-m wide rooms with 3.0 m ×3.0 m pillars, while the selective room-and-pillar mining technique consists in stoping with rooms of 4.0 m wide and pillars of 4 m ×4 m with a subsequent selective cutting of the quartz veins at the mid pillar of approximately 0.5 m high, to obtain a pillar section with an area of 3.0 m × 3.0 m. The stability and productivity analyses indicate that the selective technique obtains smaller average pillar safety factor, more rock mass displacement, more extraction and selectivity ratios, and ore grade improvement, compared with the traditional technique. These results show that the selective technique is also more convenient. This proposed selective room-and-pillar mining technique is applicable to any sub-horizontal narrow quartz veins with wolfram, gold, etc. such as the famous La Rinconada gold mine in the Peruvian Andes.

  11. The radiation stability of glycine in solid CO2 - in situ laboratory measurements with applications to Mars

    CERN Document Server

    Gerakines, P A

    2015-01-01

    The detection of biologically important, organic molecules on Mars is an important goal that may soon be reached. However, the current small number of organic detections at the Martian surface may be due to the harsh UV and radiation conditions there. It seems likely that a successful search will require probing the subsurface of Mars, where penetrating cosmic rays and Solar energetic particles dominate the radiation environment, with an influence that weakens with depth. Toward the goal of understanding the survival of organic molecules in cold radiation-rich environments on Mars, we present new kinetics data on the radiolytic destruction of glycine diluted in frozen carbon dioxide. Rate constants were measured in situ with infrared spectroscopy, without additional sample manipulation, for irradiations at 25, 50, and 75 K with 0.8-MeV protons. The resulting half-lives for glycine in CO2-ice are compared to previous results for glycine in H2O-ice and show that glycine in CO2-ice is much less stable in a radia...

  12. In Situ Nitroxide-Mediated Polymerized Poly(acrylic acid as a Stabilizer/Compatibilizer Carbon Nanotube/Polymer Composites

    Directory of Open Access Journals (Sweden)

    Laurence Couvreur

    2007-11-01

    Full Text Available Carbon nanotube (CNT polymer composites were synthesized via in situ nitroxide-mediated diblock copolymerization. Poly(acrylic acid (PAA was chosen as a first block to obtain a precomposite CNT-PAA which is readily dispersible in various solvents including water. The immobilization of the stable poly(acrylic acid alkoxyamine functionality on the nanotube surface occurs during the synthesis of the first block without CNT prior treatment. The living character of this block is established by spectroscopic methods and the nature of the CNT/PAA interaction is discussed. This living first block offers the opportunity to reinitiate the polymerization of a second block that can be chosen among a wide range of monomers. This versatility is illustrated with a second block containing methyl acrylate (MA or styrene (S. Scanning and transmission electron microscopies confirm good CNT dispersion in the polymer network, while transmission electron microscopy also spots the anchorage locations of PAA on the CNT surface. Such nanotubes wrapped by diblock copolymers can be dispersed in various polymer matrices to create CNT—polymer composites. Conductivity measurements show that these composites obey a percolation-like power law with a low percolation threshold (less than 0.5 vol% and a high maximum conductivity (up to 1.5 S/cm at room temperature.

  13. The radiation stability of glycine in solid CO2 - In situ laboratory measurements with applications to Mars

    Science.gov (United States)

    Gerakines, Perry A.; Hudson, Reggie L.

    2015-05-01

    The detection of biologically important, organic molecules on Mars is an important goal that may soon be reached. However, the current small number of organic detections at the martian surface may be due to the harsh UV and radiation conditions there. It seems likely that a successful search will require probing the subsurface of Mars, where penetrating cosmic rays and solar energetic particles dominate the radiation environment, with an influence that weakens with depth. Toward the goal of understanding the survival of organic molecules in cold radiation-rich environments on Mars, we present new kinetics data on the radiolytic destruction of glycine diluted in frozen carbon dioxide. Rate constants were measured in situ with infrared spectroscopy, without additional sample manipulation, for irradiations at 25, 50, and 75 K with 0.8-MeV protons. The resulting half-lives for glycine in CO2-ice are compared to previous results for glycine in H2O-ice and show that glycine in CO2-ice is much less stable in a radiation environment, with destruction rate constants ?20-40 times higher than glycine in H2O-ice. Extrapolation of these results to conditions in the martian subsurface results in half-lives estimated to be less than 100-200 Myr even at depths of a few meters.

  14. Application of in situ hybridization, cytochemical and immunocytochemical techniques for the investigation of peroxisomes. A review including novel data. Robert Feulgen Prize Lecture 1997.

    Science.gov (United States)

    Baumgart, E

    1997-09-01

    In situ hybridization, cytochemical and immunocytochemical techniques have contributed significantly to the understanding of the biology of peroxisomes, since they permit in situ demonstration of the sites of synthesis and distribution of peroxisomal proteins without the necessity of homogenization and subcellular fractionation of tissues or cultured cells. This article reviews the results of research on mammalian peroxisomal metabolism, biogenesis and proliferation in which morphological techniques have played a significant role in the elucidation of the biological problem. Some new data on peroxisomal heterogeneity and morphogenesis are included. The morphological methods applied have made it possible to characterize the differences in distribution of mRNAs encoding peroxisomal proteins in different tissues, as well as to monitor the marked heterogeneity in the protein composition and in the activity of specific enzymes in the peroxisomal population of single cells, or in tissues with complex organization (e.g. liver and kidney). In addition, the dynamic alterations and high plasticity of the peroxisomal compartment--partly dependent on contact of the peroxisomes to the microtubular network-are presented. PMID:9342614

  15. Novel implementation of the use of the EPR-in situ technique (Electrochemical potentiodynamic reactivation) to identify intergranular corrosion susceptability of stainless steels exposed to high temperatures

    International Nuclear Information System (INIS)

    Austenitic stainless steels (18 % Cr), are often used in pieces that are exposed to temperatures of 450oC to 900oC (heat exchangers). At these temperatures sensibilization occurs on the grain boundaries, becoming a key factor in the appearance of intergranular corrosion. In order to prevent this phenomena from occurring 0.3% to 0.8% of niobium is added as an alloying element in the manufacturing process, which prevents the carbon present in the steel combines with the chromium, avoiding the formation of carbides. An electrochemical method for in-situ application was developed to evaluate the corrosive behavior of stainless steel and its susceptibility and degree of sensibilizaton to an intergranular attack. This work shows the effectiveness of this technique in evaluating niobium's inhibitory effect in preventing the formation of chromium carbides on the grain boundaries of 18% chromium steel, and also shows the technique's potentiality in determining how susceptible these steels are to intercrystalline corrosion

  16. Study on development of evaluation technique of in-situ tracer test in Horonobe Underground Research Laboratory project (Contract research)

    International Nuclear Information System (INIS)

    In the Horonobe Underground Research Laboratory Project, in-situ tracer tests are valuable and important as the investigations to obtain the mass transportation data of fractures in hostrock. However, it is difficult that the in-situ tests are executed under various conditions due to long test period and the tests results are evaluated about permeable heterogeneity in a fracture and/or scale effects. In this study, a number of tracer tests are simulated in a fictitious single plate fracture generated on computer. And the transport parameters are identified by fitting one- and two-dimensional models to the breakthrough curves obtained from the simulations in order to investigate the applicability of these models to the evaluation of in-situ tracer test. As a result, one-dimensional model yields larger longitudinal dispersion length than two-dimensional model in the both cases of homogeneous and heterogeneous hydraulic conductivity fields of the fictitious fracture. This is because that the effect of transverse dispersion has to be included in the longitudinal dispersion length parameter in the one-dimensional model. It is also found that the larger dipole ratio and the larger natural groundwater flow crossing the flow generated between two boreholes make the identified longitudinal dispersion length larger. And, the longitudinal dispersion length identified from a tracer test is smaller and/or larger than the macroscopic longitudinal dispersion length identified from whole fracture. It is clarified that these are occurred by shorter or longer distance between boreholes compare to the correlation length of geostatistical heterogeneity of fictitious fracture. (author)

  17. In-Situ Uranium Stabilization Through Polyphosphate Injection: Pilot-Scale Treatability Test at the 300 Area, Hanford Site

    International Nuclear Information System (INIS)

    This paper describes the pilot-scale treatability test that was conducted to evaluate the efficacy of using a polyphosphate injection approach to treat uranium-contaminated groundwater in situ within the 300 Area aquifer at the Hanford Site in Richland, Washington. Primary test objectives were to assess 1) direct treatment of available uranium contributing to the groundwater plume through precipitation of the uranyl-phosphate mineral autunite, and 2) emplacement of secondary-treatment capacity via precipitation of the calcium-phosphate mineral apatite, which acts as a long-term sorbent for uranium. Based on an injection design analysis that incorporated results from both bench-scale testing and site-specific characterization activities, a three-phase injection approach was selected for field-scale testing. This approach consisted of 1) an initial polyphosphate injection to facilitate direct treatment of aqueous uranium in the pore space, 2) a second phase consisting of a calcium chloride injection to provide an available calcium source for the creation of apatite, and 3) a subsequent polyphosphate injection to supply a phosphate source for the formation of apatite. The total-solution volume injected during this field test was approximately 3.8 million L (1 million gal). Results from this investigation will be used to identify implementation challenges and investigate the technology's ability to meet remedial objectives. In addition, data from this test will provide vaition, data from this test will provide valuable information for designing a full-scale remedial action for uranium in groundwater beneath the 300 Area of the Hanford Site, and a detailed understanding of the fundamental underpinnings necessary to evaluate the efficacy and potential for utilization of the polyphosphate technology at other sites with varying geochemical and hydrodynamic conditions. (authors)

  18. Techniques to improve maneuver stability characteristics of a nonlinear wide-body transport airplane in cruise flight

    Science.gov (United States)

    Grantham, William D.; Person, Lee H., Jr.; Bailey, Melvin L.; Tingas, Stephen A.

    1994-01-01

    The maneuver control stability characteristics of an aircraft are a flying qualities parameter of critical importance, to ensure structural protection as well as adequate predictability to the pilot. Currently, however, maneuver stability characteristics are not uniquely addressed in the Federal Aviation Regulations (FAR) Part 25, for transport aircraft. In past transport category certification programs, the Federal Aviation Administration (FAA) has used a combination of requirements (longitudinal control, vibration and buffeting, high-speed characteristics, and out-of-trim characteristics) to ensure safe and controllable maneuver stability characteristics over a range of flight conditions and airplane configurations. Controversies exist regarding each of these regulations, however, and considerable expenditures in terms of design studies and testing time have resulted from the requirements. It is also recognized that additional engineering guidance is needed for identifying acceptable nonlinear maneuver stability characteristics, particularly as they relate to relaxed stability, highly augmented transport configurations. The current trend in large aircraft design is toward relaxed, or even negative, static margins for improved fuel efficiency. The advanced flight control systems developed for these aircraft, in many instances, have rendered current aforementioned maneuver stability criteria either too stringent or of little practical use. Current design requirements do not account for these advanced designs. The objective was to evaluate a broad spectrum of linear and nonlinear longitudinal stability characteristics to generate data for defining satisfactory and unacceptable maneuver characteristics, as defined by pilot opinion. Primary emphasis was placed on two techniques of varying column force per normal acceleration. This study was a joint venture with four pilots participating; one from NASA, one from the FAA, and two from industry.

  19. Organic aerosol composition measurements with advanced offline and in-situ techniques during the CalNex campaign

    Science.gov (United States)

    Timkovsky, J.; Chan, A. W. H.; Dorst, T.; Goldstein, A. H.; Oyama, B.; Holzinger, R.

    2014-12-01

    Our understanding of formation processes, physical properties and climate/health effects of organic aerosols is still limited in part due to limited knowledge of organic aerosol composition. We present speciated measurements of organic aerosol composition by two methods: in-situ thermal-desorption proton-transfer-reaction mass spectrometry (TD-PTR-MS) and offline two-dimensional gas chromatography with a time-of-flight mass spectrometer (GC×GC/TOF-MS). 153 compounds were identified using the GC×GC/TOF-MS, 123 of which were matched with 64 ions observed by the TD-PTR-MS. A reasonable overall correlation of 0.67 (r2) was found between the total matched TD-PTR-MS signal (sum of 64 ions) and the total matched GC×GC/TOF-MS signal (sum of 123 compounds). A reasonable quantitative agreement between the two methods was observed for most individual compounds with concentrations which were detected at levels above 2 ng m-3 using the GC×GC/TOF-MS. The analysis of monocarboxylic acids standards with TD-PTR-MS showed that alkanoic acids with molecular masses below 290 amu are detected well (recovery fractions above 60%). However, the concentrations of these acids were consistently higher on quartz filters (quantified offline by GC×GC/TOF-MS) than those suggested by in-situ TD-PTR-MS measurements, which is consistent with the semivolatile nature of the acids and corresponding positive filter sampling artifacts.

  20. Formation of Cu2SnSe3 from stacked elemental layers investigated by combined in situ X-ray diffraction and differential scanning calorimetry techniques

    International Nuclear Information System (INIS)

    Highlights: • In situ investigation revealed intermetallic compounds and Cu2SnSe3 formations. • CuSe phase dominates binary phase formations at a low annealing temperature. • SnSe forms from liquid phase reaction of Sn and Se. • Binary Cu-selenide phase exerts sequential phase decompositions. • Crystalline Cu2SnSe3 forms above 450 °C. -- Abstract: Stacked elemental layers of Mo/Cu/Sn and Mo/Cu/Sn/Se were employed as samples for investigating the formation reaction of Cu–Sn intermetallic compounds as well as Cu2SnSe3 phases by in situ technique of X-ray diffraction and differential scanning calorimetry. The use of a combined in situ technique allows a real-time observation on solid-state reactions as well as any crystalline phase changes during annealing towards the crystallization of Cu2SnSe3. It is found that Cu and Sn form intermetallic compounds of Cu6Sn5, Cu3Sn and Cu41Sn11 as the annealing temperature rises from 30 to 550 °C. The reaction of Se with Cu to form a CuSe phase dominates the binary phase formation at a low annealing temperature. The annealing of a stacked Mo/Cu/Sn/Se layer suggests that only Cu6Sn5 intermetallic compound directly acts as a reactant for the Cu-selenide phase formation. A SnSe phase mostly forms from a liquid-state reaction of Sn and Se above the Sn melting point. The in situ investigation also reveals a complete set of Cu-selenide peritectic decompositions of CuSe2 ? CuSe ? Cu1.8Se at 360 and 412 °C. The formation of Cu2SnSe3 phase starts at 450 °C as a product from a reaction between Cu1.8Se and SnSe in a presence of liquid Se. Comparisons on the initial formation temperatures of all involved phases and on the formation pathways between Cu2SnSe3 and Cu2SnS3 are discussed as well

  1. Compact and inexpensive frequency stabilization technique for 850-nm vertical cavity surface emitting lasers based on Fabry-Perot resonator

    Science.gov (United States)

    Miura, Yukio; Nakajima, Jun; Mizutani, Kouki; Sasaki, Wakao

    2007-09-01

    We have demonstrated a compact and inexpensive frequency stabilization technique for commercially available 1mW, 850nm vertical cavity surface emitting laser (VCSEL) using a Fabry-Perrot cavity as frequency standard. Recently VCSEL has been widely prevailed for uses of low cost and small sized sensors, since it may afford low power operations and manufacturing costs in comparison with edge emitting type Fabry-Perrot laser diodes. Therefore, a highly versatile and inexpensive frequency stabilized coherent light source which can be mass producible will be available if the frequency stabilization for this type of VCSEL's is carried out. Generally, it has been commonly accepted that a satisfactory degree of coherence may be easily obtained from VCSEL's without any additional frequency stabilization technique since highly reflective coatings are to be put on their laser cavity edges. Nevertheless, some VCSEL devices, especially inexpensive type commercial products show multi-mode behaviors along with polarization instabilities. In the present work, as a simple and inexpensive approach to commercially available VCSEL devices, we have demonstrated a frequency stabilization scheme using a Fabry-Perrot cavity. The error signal was derived by phase sensitive detection for the transmitted light from the Fabry-Perrot resonator. Thus, the lasing frequency of the VCSEL was locked to the zero-crossing of the error signal by negative feedback for injection current via a PID controller. As a result, we have successfully suppressed the amount of frequency fluctuations in the free-running VCSEL of as much as 2GHz to be within 500MHz at measuring time of 30sec, that is, the attained Allan variance is 4.1×10E-8.

  2. Maintaining stability of standalone Micro-Grid by employing electrical and mechanical fault ride through techniques upon fixed speed wind generation systems

    International Nuclear Information System (INIS)

    Highlights: • This paper presented two fault ride through techniques for fixed speed wind systems. • The first technique is implemented by inserting a series resistance with the terminals of wind generator. • Second technique is performed by adapting the gear ratio to spill some mechanical power. - Abstract: This study presents two different Fault Ride Through (FRT) techniques to keep and restore stability of Fixed Speed Wind Generation system (FSWGs) installed in standalone Micro-Grid (MG). The first technique is an electrical FRT and is implemented by inserting a series resistance with the terminals of FSWGs during fault to maintain reasonable value of terminal voltage and consequently help stability restoration. The second controller is a mechanical FRT controller and is performed by change the gear ratio of wind generation systems to spill part of extracted mechanical power and consequently improving stability issue. Obtained results proved that each controller able to maintain the stability of FSWGs under the most severe disturbance conditions (400 ms three phase fault at FSWGs terminals). The first controller is faster than the second controller in restoring FSWGs stability. Superior results and performances are obtained when the two FRT techniques are employed simultaneously. Without employing any one of the two FRT techniques, FSWGs is not able to maintain or restore its stability after fault clearing. Consequently, MG will lose one of its micro-sources and cannot keep its stability during the standalone mode, unless load shedding strategy is activated. The two proposed controllers are simple, effective, and economical attractive

  3. In situ HVEM studies on the effects of electron-irradiation on the thermal stability of Ni-based amorphous alloys

    International Nuclear Information System (INIS)

    In situ high voltage electron microscope (HVEM) studies on the thermal stability of splat-cooled Ni-based amorphous alloys were made and three kinds of accelerated crystallization modes were observed during bombardment by focused 1000 keV electrons. In one case the crystalline grains induced by irradiation were coarser near the edge of the irradiated region (IR) than in other parts. This type of crystallization was observed in Ni75B17Si8 and Ni75B15Si8C2 amorphous alloys subjected to a continuous increase in temperature of irradiation. The second case was one where there was no appreciable difference in size distribution of the crystalline grains throughout the IR. This type was observed in a Ni80P10B10 amorphous alloy which again was subjected to a continuous increase in irradiation temperature and also observed in Ni75B17Si8 amorphous alloy irradiated during isothermal annealing. In these two cases, the crystalline grains induced during irradiation did not cover the whole of the IR before crystallization started in the unirradiated region. In the third case, however, the amorphous phase completely disappeared from the IR before crystallization in the unirradiated region occurred. This type of crystallization was observed in Ni80P20 amorphous alloy whilst the temperature was being increased continuously derature was being increased continuously during irradiation. (author)

  4. Simulation Techniques of Electrical Power System Stability Studies Utilizing Matlab/Simulink

    Directory of Open Access Journals (Sweden)

    Naresh K. Tanwani*1

    2014-03-01

    Full Text Available Maintaining synchronism between different parts of power system (PS is getting difficult over time. The fact that growth of interconnected system is a continuous process, also these systems have been extended in different regions. In this research work steady state (SS and transient stabilities along with swing equation and numerical solution using MATLAB / Simulink are studied. This work is done in two steps. In the first step, proper assumptions are made to linearize the system and then, the transfer function models of this system are developed for stability analysis. The performance of proposed linearized model of synchronous machine during normal and disturbed conditions is focused in Matlab/Simulink. This gives the understanding of the transient and dynamic analysis of PS stabilities. In the second step, the proposed methodology of the power system stability (PSS with steady state (including transient and dynamic analysis, the application to sudden increase in power input, and the application of three-phase fault have been examined using Matlab coding (m-files along with simulation models (Simulink. This makes power system stability studies easier to understand. The study also gives good understanding of maintaining reliable position of the system and new design of generating and transmitting plants. Furthermore, it provides information of relaying system and critical clearing time of circuit breakers, voltage levels and transfer capabilities between systems. Use of MATLAB/SIMULINK for this purpose, provides supplement for implementing numerical solution in the field of power system and its analysis for students, engineers and researchers.

  5. Fluorescence in situ hybridization techniques (FISH) to detect changes in CYP19a gene expression of Japanese medaka (Oryzias latipes)

    International Nuclear Information System (INIS)

    The aim of this study was to develop a sensitive in situ hybridization methodology using fluorescence-labeled riboprobes (FISH) that allows for the evaluation of gene expression profiles simultaneously in multiple target tissues of whole fish sections of Japanese medaka (Oryzias latipes). To date FISH methods have been limited in their application due to autofluorescence of tissues, fixatives or other components of the hybridization procedure. An optimized FISH method, based on confocal fluorescence microscopy was developed to reduce the autofluorescence signal. Because of its tissue- and gender-specific expression and relevance in studies of endocrine disruption, gonadal aromatase (CYP19a) was used as a model gene. The in situ hybridization (ISH) system was validated in a test exposure with the aromatase inhibitor fadrozole. The optimized FISH method revealed tissue-specific expression of the CYP19a gene. Furthermore, the assay could differentiate the abundance of CYP19a mRNA among cell types. Expression of CYP19a was primarily associated with early stage oocytes, and expression gradually decreased with increasing maturation. No expression of CYP19a mRNA was observed in other tissues such as brain, liver, or testes. Fadrozole (100 ?g/L) caused up-regulation of CYP19a expression, a trend that was confirmed by RT-PCR analysis on excised tissues. In a combination approach with gonad histology, it could be shown that the increase in CYP19a expression as measured by RT-P in CYP19a expression as measured by RT-PCR on a whole tissue basis was due to a combination of both increases in numbers of CYP19a-containing cells and an increase in the amount of CYP19a mRNA present in the cells

  6. Susceptibility to Coffee Staining during Enamel Remineralization Following the In-Office Bleaching Technique : An In Situ Assessment

    DEFF Research Database (Denmark)

    Mori, Aline Akemi; Lima, Fernanda Ferruzzi

    2015-01-01

    PURPOSE: To assess in situ the enamel mineralization level and susceptibility to coffee staining after in-office bleaching. MATERIALS AND METHODS: Thirty-six human dental fragments assembled into intraoral devices were bleached with 35% hydrogen peroxide and treated as follows: (group 1) no contact with coffee; (group 2) immersion in a coffee solution for 30 minutes daily for 7 days, starting 1 week after bleaching; and (group 3) immersion in a coffee solution for 30 minutes daily for 14 days, starting immediately after bleaching. Enamel mineralization and color were assessed before bleaching (T1), immediately after bleaching (T2), and after 7 (T3) and 14 days (T4). The CIE whiteness index (W*) and closeness to white (?W*) following bleaching and/or immersion in coffee were calculated. Data were analyzed with Friedman and Wilcoxon tests or Kruskal-Wallis and Mann-Whitney U-tests (??=?0.05). RESULTS: Significant differences in the mineralization levels were observed as a function of time. No significant differences in W* were observed between groups, nor was W* significantly different at T3 and T4. Similar ?W* was observed between groups after 7 or 14 days. CONCLUSIONS: The mineral loss after in-office bleaching was progressively reversed by contact with saliva for 14 days. The whiteness index was not affected by contact with coffee during the remineralization period. CLINICAL SIGNIFICANCE: The results of this in situ study suggest that the mineral loss caused by in-office dental bleaching is minimal and is partly compensated by remineralization due to contact with saliva. Additionally, whiteness was not affected by daily exposition to coffee during the enamel remineralization, which indicates that avoiding the consumption of coffee immediately following in-office bleaching is unnecessary.

  7. Design and development of technique for in-situ response time measurement of RTDs and implementation aspects for nuclear power plant application

    International Nuclear Information System (INIS)

    Temperature sensors are used for the measurement of important parameters in Nuclear Power plant such as differential temperature across reactor core inlet and outlet, steam generator inlet and outlet temperature, measurement of surface temperature of selected fuel channels. These measurements are used to detect temperature transients due to process disturbances and are used to initiate safety action. Hence it is important that the temperature sensors (Resistance Temperature detectors (RTDs), thermocouples) used are accurate, well calibrated, and have fast response time. However, the response time of RTDs and thermocouples degrades during operation due to several factors such as corrosion of the thermowells, development of air gaps within the temperature sensor, vibrations, process pressure and temperature. Standards such as IEEE Std. 279-1991 requires that means be provided for checking the operational availability of each protection system input sensors during reactor operation. It also specifies a mandatory requirement that all the sensors installed in a nuclear power plant shall have in-situ periodic testability of parameters important to safety. In this paper, a technique for in-situ measurement of response time of RTDs and implementation aspects for plant application have been presented. (author)

  8. Laser Frequency Stabilization for Coherent Lidar Applications using Novel All-Fiber Gas Reference Cell Fabrication Technique

    Science.gov (United States)

    Meras, Patrick, Jr.; Poberezhskiy, Ilya Y.; Chang, Daniel H.; Levin, Jason; Spiers, Gary D.

    2008-01-01

    Compact hollow-core photonic crystal fiber (HC-PCF)gas frequency reference cell was constructed using a novel packaging technique that relies on torch-sealing a quartz filling tube connected to a mechanical splice between regular and hollow-core fibers. The use of this gas cell for laser frequency stabilization was demonstrated by locking a tunable diode laser to the center of the P9 line from the (nu)1+(nu)3 band of acetylene with RMS frequency error of 2.06 MHz over 2 hours. This effort was performed in support of a task to miniaturize the laser frequency stabilization subsystem of JPL/LMCT Laser Absorption Spectrometer (LAS) instrument.

  9. Study of phase stability of MnCr using the augmented space recursion based orbital peeling technique

    International Nuclear Information System (INIS)

    In an earlier communication we have developed a recursion based approach to the study of phase stability and transition of binary alloys [K. Tarafder, M. Rahaman, D. Paudyal, B. Sanyal, O. Eriksson, A. Mookerjee, Physica B 403 (2000) 4111]. We had combined the recursion method introduced by Haydock et al. [J. Phys. C Solid State Phys. 5 (1972) 2485] and the our augmented space approach [A. Mookerjee, J. Phys. C Solid State Phys. 6 (1973) 1340] with the orbital peeling technique proposed by Burke [Surf. Sci. 58 (1976) 349] to determine the small energy differences involved in the discussion of phase stability. We extend that methodology for the study of MnCr alloys.

  10. Combined Characterization Techniques to Understand the Stability of a Variety of Organic Photovoltaic Devices - the ISOS-3 inter- laboratory collaboration

    DEFF Research Database (Denmark)

    Lira-Cantu, Monica; Tanenbaum, David M.

    2012-01-01

    This work is part of the inter-laboratory collaboration to study the stability of seven distinct sets of state-of-the-art organic photovoltaic (OPVs) devices prepared by leading research laboratories. All devices have been shipped to and degraded at the Danish Technical University (DTU, formerly RISO-DTU) up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. In this work we present a summary of the degradation response observed for the NREL sample, an inverted OPV of the type ITO/ZnO/P3HT:PCBM/PEDOT:PSS/Ag/Al, under full sun stability test. The results reported from the combination of the different characterization techniques results in a proposed degradation mechanism. The final conclusion is that the failure of the photovoltaic response of the device with time under full sun solar simulation, is mainly due to the degradation of the electrodes and not to the active materials of the solar cell.

  11. Predictive tools and data needs for long term performance of in-situ stabilization and containment systems: DOE/OST stabilization workshop, June 26-27, Park City, Utah

    International Nuclear Information System (INIS)

    This paper summarizes the discussion within the Predictive Tools and Data Needs for Long Term Performance Assessment Subgroup. This subgroup formed at the DOE Office of Science and Technology workshop to address long-term performance of in situ stabilization and containment systems. The workshop was held in Park City, Utah, 26 and 27 June, 1996. All projects, engineering and environmental, have built-in decision processes that involve varying risk/reward scenarios. Such decision-processes maybe awkward to describe but are utilized every day following approaches that range from intuitive to advanced mathematical and numerical. Examples are the selection of components of home sound system, the members of a sports team, investments in a portfolio, and the members of a committee. Inherent in the decision method are an understanding of the function or process of the system requiring a decision or prediction, an understanding of the criteria on which decisions are made such as cost, performance, durability and verifiability. Finally, this process requires a means to judge or predict how the objects, activities, people and processes being analyzed will perform relative to the operations and functions of the system and relative to the decision criteria posed for the problem. These risk and decision analyses are proactive and iterative throughout the life of a remediation project. Prediction inherent to the analyses are based on intuition, experience, trial and error, and system analysis often using numerical approaches

  12. The karyotype of Festucopsis serpentini (Poaceae Triticeae) from Albania studied by banding techniques and in situ hybridization

    DEFF Research Database (Denmark)

    Linde-Laursen, I.; Seberg, O.

    1996-01-01

    The karyotypes of two populations of Festucopsis serpentini (2n = 2x = 14) endemic to Albania were investigated in detail by Giemsa C- and N-banding, AgNO3 staining, and in situ hybridization with an rDNA probe. The complements consisted of 14 large chromosomes, 10 metacentric and 4 SAT-chromosomes, a metacentric and a submetacentric pair. SAT-chromosomes from one population carried exclusively minute satellites, whereas SAT-chromosomes from another population also carried larger polymorphic satellites, suggesting a geographical differentiation. The existence of four chromosomes with nucleolus forming activity was established through AgNO3 staining; however, the rDNA probe additionally hybridized to intercalary positions in the short arms of two metacentric chromosomes revealing two inactive rDNA sites. C-banding patterns comprised from zero and up to four very small to larger, generally telomeric bands per chromosome giving low levels of constitutive heterochromatin. Similarities in chromosome morphology andC-banding patterns identified the homologous relationships of all chromosomes in one population, but of three pairs only in the other. Reliable identification of homologous chromosomes between plants was only possible for the SAT-chromosomes. A comparison between the C-banded karyotypes of F. serpentini and Peridictyon sanctum supports their position in two genera.

  13. In situ observation of columnar-to-equiaxed transition in directional solidification using synchrotron X-radiation imaging technique

    Energy Technology Data Exchange (ETDEWEB)

    Dong Qing [State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhang Jiao, E-mail: zj119@sjtu.edu.cn [State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China); Dong Jinfang [State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China); Xie Honglan; Li Zhijun [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Shanghai 215600 (China); Dai Yongbing; Liu Yang; Sun Baode [State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer In situ observation of a columnar-to-equiaxed transition. Black-Right-Pointing-Pointer There is a gradual change in the density of the melt at the mush-liquid interface. Black-Right-Pointing-Pointer A mechanical analysis on dendrite detachment was carried out. Black-Right-Pointing-Pointer The transition was explained based on dendrite detachment and fragment movement. - Abstract: A columnar-to-equiaxed transition (CET) was induced by controlling the cooling rate in the directional solidification of an Al-15 wt.% Cu alloy. The morphological evolution of the mush-liquid interface in CET was tracked and recorded by X-ray imaging. The dendrite growth and detachment, solute distribution at the growth front and excessive solute enrichment in the liquid pockets were clearly observed. Based on the observations, it was found that there is an obvious increase in melt density in the liquid pocket due to the excessive solute enrichment. The density difference between the melt and the solid is an important reason for dendrite detachment and fragment movement, which is considered as the key to the inducement of CET. Finally, the CET process and the growth of equiaxed dendrites at the mush-liquid interface were described from the viewpoint of dendrite detachment.

  14. Structural inhomogeneity of superconducting ex situ MgB2/Cu wires made by the powder-in-tube technique

    International Nuclear Information System (INIS)

    Single core MgB2 wires have been made by the powder-in-tube (PIT) method using commercial MgB2 powder (Alfa Aesar). Using the two-axial rolling process, composites have been made in a Cu sheath. Energy dispersive x-ray (EDX) mapping and scanning electron microscopy backscattered electron observations prove that there is high element segregation (phase inhomogeneity) for as-rolled and as-sintered wires, although the wire after sintering is more inhomogeneous than the as-rolled (non-sintered) wire. X-ray diffraction diffractograms confirm the presence of isotropy and the absence of texturization in the 'macroscopic' phase within the MgB2 cores, despite their thermomechanical history. The observed decrease in the value of Jc in the wire after sintering was attributed to macroscopic cracking and the worsening of the intergrain connectivity. EDX line scans have also shown high anisotropy and high inhomogeneity in the distribution of elements within the MgB2 cores. Inhomogeneity in the final product (wires) has resulted from the high macroscopic inhomogeneity observed in the starting MgB2 powder. The Cu sheath has been shown to be neutral (non-poisoning) for MgB2 cores made ex situ. However, due to its softness, it cannot properly constrain the MgB2 core or give enough support required for adequate grain connectivity. (author)

  15. Structural inhomogeneity of superconducting ex situ MgB2/Cu wires made by the powder-in-tube technique

    Science.gov (United States)

    Pachla, W.; Presz, A.; Diduszko, R.; Kovác, P.; Husek, I.

    2002-09-01

    Single core MgB2 wires have been made by the powder-in-tube (PIT) method using commercial MgB2 powder (Alfa Aesar). Using the two-axial rolling process, composites have been made in a Cu sheath. Energy dispersive x-ray (EDX) mapping and scanning electron microscopy backscattered electron observations prove that there is high element segregation (phase inhomogeneity) for as-rolled and as-sintered wires, although the wire after sintering is more inhomogeneous than the as-rolled (non-sintered) wire. X-ray diffraction diffractograms confirm the presence of isotropy and the absence of texturization in the 'macroscopic' phase within the MgB2 cores, despite their thermomechanical history. The observed decrease in the value of Jc in the wire after sintering was attributed to macroscopic cracking and the worsening of the intergrain connectivity. EDX line scans have also shown high anisotropy and high inhomogeneity in the distribution of elements within the MgB2 cores. Inhomogeneity in the final product (wires) has resulted from the high macroscopic inhomogeneity observed in the starting MgB2 powder. The Cu sheath has been shown to be neutral (non-poisoning) for MgB2 cores made ex situ. However, due to its softness, it cannot properly constrain the MgB2 core or give enough support required for adequate grain connectivity.

  16. Nanostructured PbO materials obtained in situ by spray solution technique for Li-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Konstantinov, K.; Ng, S.H.; Wang, J.Z.; Wang, G.X.; Liu, H.K. [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522 (Australia); Wexler, D. [Faculty of Engineering, University of Wollongong, NSW 2522 (Australia)

    2006-09-13

    This paper describes a systematic study of the effect of various spray pyrolysis parameters, such as temperature, solution concentration and solution flow rate on the morphology, crystallization process, crystal size, specific surface area and electrochemical performance of in situ prepared {alpha}-PbO spherically agglomerated nano-structured powders. Different analytical methods such as XRD, SEM, TEM, BET gas sorption specific surface area measurements and electrochemical tests were performed. Crystallites in the range of 20-120nm and easily dispersed powders were reproducibly prepared by optimization of the spray conditions. An increase of the temperature from 600 to 800{sup o}C was found to lead to a three times increase in the average crystal size, from 31 to 102nm. An increase of concentration from 0.15 to 0.5M dramatically suppresses the crystal size from 127 to 25nm. The BET surface area of sprayed PbO powders is increased up to 6.6m{sup 2}g{sup -1}. For such PbO powders applied as anode materials in Li-ion batteries, we have managed to retain a reversible capacity above 60mAhg{sup -1} beyond 50 cycles. (author)

  17. Evaluation of the in situ, time-integrated DGT technique by monitoring changes in heavy metal concentrations in estuarine waters

    International Nuclear Information System (INIS)

    Various natural and anthropogenic processes influence heavy metal concentrations within estuaries. In situ, time-integrated DGT measurements made over concurrent tidal phases found significantly higher concentrations of Cu (probability p = 0.017), Zn (p = 0.003) and Ni (p = 0.003) during the flood phase, because the incoming tide passes several point sources. DGT-reactive Cu concentrations significantly decreased with increased tidal-flushing and vice versa within a marina (correlation r = -0.788, p = 0.02). DGT measurements also recorded significant increases in Cu (4 out of 4 sites, p < 0.001) and Zn (3 out of 4 sites, p ? 0.015) after a 24 mm rainfall event. Finally, DGT-reactive Cu increased significantly (p < 0.001) during peak boating times, due to increased numbers of Cu-antifouled boats. This study demonstrates that, with judicious selection of deployment times, DGT measurements enable changes in heavy metal concentrations to be related to various cycles and events within estuaries. - Demonstration of the usefulness of DGT as a monitoring tool for heavy metals in dynamic estuaries

  18. Innovative Protocols for in SITU MTBE Degradation by Using Molecular Probes-An Enhanced Chemical-Bio Oxidation Technique

    Energy Technology Data Exchange (ETDEWEB)

    Paul Fallgren

    2009-02-20

    In situ chemical oxidation (ISCO) is a common technology to cleanup petroleum hydrocarbon-contaminated soils and groundwater. Sodium percarbonate (SPC) is an oxidant which is activated by iron (Fe) to produce Fenton-like reactions. Western Research Institute, in conjunction with Regenesis and the U.S. Department of Energy, conducted a study that investigated the performance of a 'safe' oxidant, SPC, to cleanup groundwater and soils contaminated with petroleum hydrocarbons and associated contaminants (e.g., MTBE). Results from a field pilot test in Frenchglen, Oregon showed VOC concentrations in groundwater decreased substantially within 2 weeks after injecting activated SPC (RegenOx). A protocol was established for determining RegenOx TOD in soils and groundwater. Total oxidant demand tests were necessary to determine the correct dosage of RegenOx to apply in the field and sufficiently degrade the contaminants of concern. Bench studies with RegenOx showed this technology was effective in degrading diesel fuel and 1,4-dioxane. The Fe-silica activator (RegenOx Part B) was tested with another oxidant, sodium persulfate. Bench tests results showed the combination of sodium persulfate and RegenOx Part B was effective in reducing PCE, MTBE, benzene, and n-heptane concentrations in water. Overall, the results of this project indicated that most petroleum contaminants in soil and groundwater can be sufficiently degraded using the RegenOx technology.

  19. Development of in-situ UV-vis technique for the molten salt electrorefining process of uranium

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. H.; Hwang, S. C.; Kang, Y. H.; Shim, J. B.; Ahn, B. G.; Kwon, S. W.; Woo, M. S.; Lee, B. J.; Kim, E. H.; Park, S. W. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    During the last decade, interest in the pyrometallrugical treatment of spent nuclear fuel has been drastically increased because of its relatively low processing cost as well as its proliferation resistance of the nuclear fuel cycles. Similar but unique researches have been conducted by several institutions in various countries using their own strategies, i.e. IFR fuel cycle in ANL, DOVITA process in RIAR and ,OMEGA program in JAERI. The Korea Atomic Energy Research Institute (KAERI) is developing an electrorefining process using PWR surrogate spent fuels. In this fuel cycle, uranium and TRU oxides are electrochemically reduced while the rare earth oxides are intact. Thus, the prepared ingot consists of metallic uranium, TRU and rare earth oxides. The main scientific and technological interests in the electrorefining process using the electrochemically reduced fuel ingot are how to effectively partition a spent fuel into Uranium, TRU and fission products (FPs). Furthermore a systematic consideration for a series of pyrochemical treatments of the spent fuel which includes not only an electrorefining but also a cathode process has not been reported. Hence in this study, we would like to report on the methodology to recycle PWR fuel for a future use and some important results in the electrorefining of the uranium and the cathode process of the deposit. Also, in-situ UV-vis absorption spectrometry was adopted to observe the behavior of Nd{sub 2}O{sub 3} in molten salt encouraged by the recent results of Yamana et. al.

  20. Development of in-situ UV-vis technique for the molten salt electrorefining process of uranium

    International Nuclear Information System (INIS)

    During the last decade, interest in the pyrometallrugical treatment of spent nuclear fuel has been drastically increased because of its relatively low processing cost as well as its proliferation resistance of the nuclear fuel cycles. Similar but unique researches have been conducted by several institutions in various countries using their own strategies, i.e. IFR fuel cycle in ANL, DOVITA process in RIAR and ,OMEGA program in JAERI. The Korea Atomic Energy Research Institute (KAERI) is developing an electrorefining process using PWR surrogate spent fuels. In this fuel cycle, uranium and TRU oxides are electrochemically reduced while the rare earth oxides are intact. Thus, the prepared ingot consists of metallic uranium, TRU and rare earth oxides. The main scientific and technological interests in the electrorefining process using the electrochemically reduced fuel ingot are how to effectively partition a spent fuel into Uranium, TRU and fission products (FPs). Furthermore a systematic consideration for a series of pyrochemical treatments of the spent fuel which includes not only an electrorefining but also a cathode process has not been reported. Hence in this study, we would like to report on the methodology to recycle PWR fuel for a future use and some important results in the electrorefining of the uranium and the cathode process of the deposit. Also, in-situ UV-vis absorption spectrometry was adopted to observe the behavior of Nd2O3 in molteor of Nd2O3 in molten salt encouraged by the recent results of Yamana et. al

  1. Structural and optical studies of Zn1-xCdxS quantum dots synthesized by in situ technique in PVA matrix

    Science.gov (United States)

    Vineeshkumar, T. V.; Rithesh Raj, D.; Prasanth, S.; Unnikrishnan, N. V.; Philip, Reji; Sudarsanakumar, C.

    2014-11-01

    Zn1-xCdxS (x = 0.1, 0.2, 0.3, 0.4, 0.5 … 0.9) quantum dots were synthesized successfully using novel in situ technique in polyvinyl alcohol (PVA) matrix. The PVA acted as a capping agent as well as a reducing agent. The structural and optical properties of the samples were studied by X-ray diffraction (XRD), TEM analysis, UV-Visible absorption and photoluminescence spectroscopy (PL). X-ray diffraction patterns revealed cubic zinc blende phase of the samples with lattice parameter in the range 5.47-5.75 Å. Optical band gap values were calculated from the absorption spectra and observed a decreasing band gap with increasing Cd:Zn ratio. The Raman spectra were recorded using conventional Micro Raman technique. Photoluminescence spectra showed asymmetric broad emission with multiple maxima. The concentration dependent quenching of PL intensity with increasing Cd:Zn ratio was observed along with a red shift. The nonlinear optical (NLO) and limiting properties were studied using Z-scan technique.

  2. In-situ imaging of nanoscale ethanol film formation on mica surface under saturated vapor condition using VSPFM technique

    International Nuclear Information System (INIS)

    In this paper, vibrating scanning polarization force microscopy (VSPFM) technique is used to study the adsorption of ethanol gas molecules on mica surface at room temperature, and the relationship between bias and imaging quality. Experiment results showed that the best images can be acquired when the tip is biased at AC 5 V.VSPFM is a useful technique to investigate air-solid interaction. Using this technique, we found that ethanol gas molecule did not adsorb quickly on mica surface, and the ethanol adsorption behavior could not be illustrated by Langmuir adsorption model, as it took hours for the ethanol vapor molecules to be adsorbed on mica to form a nanoscale film from nucleated dots or islands. (authors)

  3. Application of stabilization techniques in the dynamic analysis of multibody systems

    Directory of Open Access Journals (Sweden)

    Hajžman M.

    2007-11-01

    Full Text Available This paper is intended to the discussion of possible methods for the solution of the motion equations of constrained multibody systems. They can be formulated in the form of differential-algebraic equations and their numerical solution brings the problems of constraint violation and numerical stability. Therefore special methods were proposed to handle these problems. Various approaches for the numerical solution of equations are briefly reviewed and the application of the Baumgarte’s stabilization method on testing examples is shown. The paper was motivated by the effort to find the suitable solution methods for the equations of motion in the form of differentialalgebraic equations using the MATLAB standard computational system.

  4. Fabrication of mullite-bonded porous SiC ceramics from multilayer-coated SiC particles through sol-gel and in-situ polymerization techniques

    Science.gov (United States)

    Ebrahimpour, Omid

    In this work, mullite-bonded porous silicon carbide (SiC) ceramics were prepared via a reaction bonding technique with the assistance of a sol-gel technique or in-situ polymerization as well as a combination of these techniques. In a typical procedure, SiC particles were first coated by alumina using calcined powder and alumina sol via a sol-gel technique followed by drying and passing through a screen. Subsequently, they were coated with the desired amount of polyethylene via an in-situ polymerization technique in a slurry phase reactor using a Ziegler-Natta catalyst. Afterward, the coated powders were dried again and passed through a screen before being pressed into a rectangular mold to make a green body. During the heating process, the polyethylene was burnt out to form pores at a temperature of about 500°C. Increasing the temperature above 800°C led to the partial oxidation of SiC particles to silica. At higher temperatures (above 1400°C) derived silica reacted with alumina to form mullite, which bonds SiC particles together. The porous SiC specimens were characterized with various techniques. The first part of the project was devoted to investigating the oxidation of SiC particles using a Thermogravimetric analysis (TGA) apparatus. The effects of particle size (micro and nano) and oxidation temperature (910°C--1010°C) as well as the initial mass of SiC particles in TGA on the oxidation behaviour of SiC powders were evaluated. To illustrate the oxidation rate of SiC in the packed bed state, a new kinetic model, which takes into account all of the diffusion steps (bulk, inter and intra particle diffusion) and surface oxidation rate, was proposed. Furthermore, the oxidation of SiC particles was analyzed by the X-ray Diffraction (XRD) technique. The effect of different alumina sources (calcined Al2O 3, alumina sol or a combination of the two) on the mechanical, physical, and crystalline structure of mullite-bonded porous SiC ceramics was studied in the second part of the project. Alumina sol was synthesized by the hydrolysis of Aluminum isopropoxide using the Yoldas method. Alumina sol was homogenous and had a needle-like shape with a thickness of 2--3 nm. Crystalline changes during the heating process of alumina sol were studied using XRD. In addition, Fourier transform infrared (FTIR) spectroscopy was performed to identify the functional groups on the alumina sol surface as a function of temperature. In the third part of the project, the feasibility of the in-situ polymerization technique was investigated to fabricate porous SiC ceramics. In this part, the mixture of SiC and calcined alumina powders were coated by polyethylene via in-situ polymerizing referred to as the polymerization compounding process in a slurry phase. The polymerization was conducted under very moderate operational conditions using the Ziegler-Natta catalyst system. Differential scanning calorimetry (DSC) and TGA analysis and morphological studies (SEM and TEM) revealed the presence of a high density of polyethylene on the surface of SiC and alumina powders. The amount of polymer was controlled by the polymerization reaction time. Most parts of particles were coated by a thin layer of polyethylene and polymer. The porous SiC ceramics, which were fabricated by these treated particles showed higher mechanical and physical properties compared to the samples made without any treatment. The relative intensity of mullite was higher compared to the samples prepared by the traditional process. The effects of the sintering temperature, forming pressure and polymer content were also studied on the physical and mechanical properties of the final product. In the last phase of this research work, the focus of the investigation was to take advantage of both the sol-gel processing and in-situ polymerization method to develop a new process to manufacture mullite-bonded porous SiC ceramic with enhanced mechanical and physical properties. Therefore, first the SiC particles and alumina nano powders were mixed in alumina sol to adjust the alumina weight to 35

  5. Evaluation of ventral stabilization techniques for thoracolumbar fractures by helical computer tomography

    International Nuclear Information System (INIS)

    Purpose: To assess the volumetric change of the implanted graft in thoracolumbar fractures treated with dorsal and ventral stabilization. Comparison of two methods of ventral stabilization to avoid loss of correction and rekyphosis. Material and Methods: 38 patients with 40 thoracolumbar fractures were treated with a tricortical bone graft of the pelvis (n = 27) or bone cement (SRS: skeletal repair system, n = 13), measuring the volume and the length of the implanted graft by helical CT (Somatom Plus 4, Siemens): after ventral stabilization, preoperative before and six month after removal of the fixateur interne. The bone and SRS volume were assessed as a product of slice thickness and cross-section, the length of the implanted graft was measured by the cranial and caudal table position. Results: Loss of graft volume between implantation and explantation of the fixateur interne was 24.3%, and between implantation and the check six months after removal 40.5%; loss of length until removal 14.6% and between implantation and six months after the removal 24.1%; no difference between the tricortical bone graft and the skeletal repair system. Conclusion: Volumetric and length study assessed by CT shows a loss of volume and length of the tricortical bone graft and the skeletal repair system with no dependence on the used material. CT enables an exact and feasible assessment of the localisation, volume, size and possible complications of the implanted bone graft and SRS. The cof the implanted bone graft and SRS. The considerable loss of volume and length of the graft is one of the reasons correction loss and rekyphosis in the stabilization of the thoracolumbar fractures. (orig.)

  6. Comparative study of different techniques of composting and their stability evaluation in municipal solid waste

    International Nuclear Information System (INIS)

    Spatial differences in the physical and chemical characteristics related to maturity of composted organic matter are strongly influenced by composting methods. For evaluation of compost maturity three locally fabricated composters (aerobic, mixed type, anaerobic) processes were examined at seven days interval up to 91 days by loading MSW along with bulking agent. Gradual changes in physico chemical characteristics (temperature, pH, moisture, CEC, humification) related to stability and maturity of compost were studied and compared. Increase in ammonia nitrogen level due to rise in temperature was maximum in aerobic process. Substantial increase in CEC in aerobic process was earlier which leads to establish the optimal degree of maturity as compared to other processes. FA and HI decrease rapidly as composting progressed. Optimal level in stability and maturity parameters like C:N, HA, DH and HR were attained earlier in aerobic process as compared to mixed type and anaerobic processes due to continuous aeration. The parameters (HR, DH, FA, HA), which indicate the compost stability were correlated among themselves. The parameters defining maturity such as CEC, ammonia nitrate and C:N ratio were also related to above mention parameters. The compost from the aerobic process provided good humus and micro nutrients. Result from this study will assist in method optimization and quality of the compost product. (author)

  7. Uranium Plume Treatability Demonstration at the Hanford Site 300 Area: Development of Polyphosphate Remediation Technology for In-Situ Stabilization of Uranium - 8070

    International Nuclear Information System (INIS)

    A groundwater plume containing uranium, originating from a combination of purposeful discharges of wastewater to cribs, trenches and ponds, along with some accidental leaks and spills during nuclear fuel fabrication activities, has persisted beneath the Hanford Site 300 Area for many years. Despite the cessation of uranium releases and the removal of shallow vadose zone source materials, the goal of less than 30 (micro)g/L has not been achieved within the anticipated 10-year time period. Polyphosphate technology has been demonstrated to delay the precipitation of phosphate phases for controlled in situ precipitation of stable phosphate phases to control the long-term fate of uranium. Precipitation occurs when polyphosphate compounds hydrolyze to yield the orthophosphate molecule. Based on the hydrolysis kinetics of the polyphosphate polymer, the amendment can be tailored to act as a time-released source of phosphate for lateral plume treatment, immediate and sustained remediation of dissolved uranium, and to preclude rapid precipitation which could result in a drastic change in hydraulic conductivity of the target aquifer. Critical to successful implementation of polyphosphate remediation technology is a site specific evaluation and optimization of multi-length polyphosphate amendment formulations. A multi-faceted approach has been taken to provide key fundamental science knowledge regarding optimization of the polyphosphate remedy through: (1) phosphorus-31 nuclear memedy through: (1) phosphorus-31 nuclear magnetic resonance to quantify the effects of Hanford groundwater and sediment on the degradation of inorganic phosphates, (2) static tests to quantify the kinetics, loading, and stability of apatite as a long-term sorbent for uranium, and (3) single-pass flow through testing to quantify the stability of autunite and apatite under relevant site conditions. Dynamic column tests were utilized to (1) optimize the composition of the polyphosphate formulation for the formation and emplacement of apatite and autunite, (2) understand the rate and extent of reaction between polyphosphate and uranium-bearing phases, (3) evaluate the effect of chemical microenvironments on the degradation of polyphosphate and the formation of autunite, and (4) quantify the mobility of polyphosphate as a function of water content. These activities are being conducted in parallel with a limited field investigation, to more accurately define the vertical extent of uranium in the vadose zone, and in the capillary fringe laterally throughout the plume

  8. In situ borehole determination of ash content of coal using gamma-gamma and neutron-gamma techniques

    International Nuclear Information System (INIS)

    During the past decade, borehole logging technology based on nuclear geophysics has found wide application in the Australian coal-mining industry. In response to the need for further improved accuracy in coal ash measurements, the Commonwealth Scientific and Industrial Research Organization, Division of Mineral Physics, has developed two new alternative techniques, which are both spectrometric. The spectrometric gamma-gamma technique is based on the existence of a simple correlation between the ash content and the equivalent atomic number and density of coal. The technique is spectrometric in that it records and uses the count rates in several windows of the backscatter spectrum. These count rates and their selected ratios describe the changes in spectral shape which are due to ash content variations. The spectrometric neutron-gamma method is suitable where the probe responses are required for specific elemental contents. Consequently, the method tolerates larger variations in ash composition for accurate measurement than does the gamma-gamma method. Both methods have been tested at several coal deposits in New South Wales and Queensland. For both techniques, RMS deviations between nuclear assay and chemical analysis are typically 2% ash in the range 5 to 40% ash. Both techniques are currently undergoing commercial development under the name of SIROLOG. The SIROLOG technology is designed to accommodate logging speeds up to 4m.min-1. However, the gamma-gammamin-1. However, the gamma-gamma probe uses gamma-ray sources of strength two orders of magnitude smaller than that of sources used in commercial probes. The logging system provides information on ash content in 5 cm intervals if required, although the vertical resolution of the probes is 30-35 cm. (author)

  9. Enhanced cycle stability of micro-sized Si/C anode material with low carbon content fabricated via spray drying and in situ carbonization

    International Nuclear Information System (INIS)

    Highlights: • Micro-sized Si/C composites were fabricated via. spray drying and carbonization. • Multi-morphology carbon was formed in the Si/C composites. • Si/C composite with 5.6 wt.% C provides significant improved cycling stability. • Multi-morphology carbon plays effective role in improving the electrochemical property. • The method provides potential for mass production of superior Si-based anode materials. - Abstract: Micro-sized Si/C composites with in situ introduced carbon of multi-morphology were fabricated via spray drying a suspension of commercial micro-sized Si and citric acid followed by a carbonization. Different ratios of Si to citric acid were used to optimize the composition and structure of the composites and thus the electrochemical performance. Carbon flakes including crooked and flat ones were well dispersed in between the Si particles, forming Si/C composites. Floc-like carbon layers and carbon fragments were also found to cover partially the Si particles. The Si/C composite with a low carbon content of 5.6 wt.% provides an initial reversible capacity of 2700 mA h/g and a capacity of 1860 mA h/g after 60 cycles at a current density of 100 mA/g as anode material for lithium-ion batteries (LIBs), which are much higher than those of pristine Si and the Si/C composites with higher carbon content. The mechanism of the enhancement of electrochemical performance of the micro-sized Si/C composite is discussed. The fabrication method and the structure design of the composites offer valuable potential in developing adaptable Si-based anode materials for industrial applications

  10. In Situ Object Counting System (ISOCS) Technique: Cost-Effective Tool for NDA Verification in IAEA Safeguards

    International Nuclear Information System (INIS)

    Uranium materials measurements using the ISOCS technique play an increasing role in IAEA verification activities. This methodology provides high uranium/plutonium sensitivity and a low detection limit together with the capability to measure items with different shapes and sizes. In addition, the numerical absolute efficiency calibration of a germanium detector which is used by the technique does not require any calibration standards or reference materials. ISOCS modelling software allows performing absolute efficiency calibration for items of arbitrary container shape and wall material, matrix chemical composition, material fill-height, uranium or plutonium weight fraction inside the matrix and even nuclear material/matrix non-homogeneous distribution. Furthermore, in a number of cases, some key parameters such as matrix density and U/Pu weight fraction can be determined along with analysis of nuclear material mass and isotopic composition. These capabilities provide a verification solution suitable for a majority of cases where quantitative and isotopic analysis should be performed. Today, the basic tool for uranium and plutonium mass measurement used in Safeguards verification activities is the neutron counting technique which employs neutron coincidence and multiplicity counters. In respect to the neutron counting technique, ISOCS calibrated detectors have relatively low cost. Taking into account its advantages, this methodology becomes a cost-effective solution for nuclear material NDA verification. At present, the Agency uses ISOCS for quantitative analysis in a wide range of applications: - Uranium scrap materials; - Uranium contaminated solid wastes; - Uranium fuel elements; - Some specific verification cases like measurement of Pu-Be neutron sources, quantification of fission products in solid wastes etc. For uranium hold-up measurements, ISOCS the only available methodology for quantitative and isotopic composition analysis of nuclear materials deposited in process equipment. With U.S. support program funding, together with the ISOCS developer Canberra Inc, the IAEA manages a task on development of 'Advanced ISOCS software' to provide new functionality with self-modelling capabilities for absolute detection efficiency calibration (software self-calibration) and simplifies the usage of the technique, reducing the required level of expertise necessary for ISOCS analysis. In the framework of this task, the IAEA is also planning to conduct a pilot training course on the technique for IAEA inspectors. (author)

  11. Demonstration of In-Situ Stabilization of Buried Waste at Pit G-11 at the Brookhaven National laboratory Glass Pits Disposal Site

    International Nuclear Information System (INIS)

    In 1989 BNL was added to the EPAs National Priorities List. The site is divided into seven operable units (OU). OU-I includes the former landfill area. The field task site is noted as the AOC 2C Glass Holes location. Beginning in the 1960s and continuing into the 1980s, BNL disposed of laboratory waste (glassware, chemicals and animal carcasses) in numerous shallow pits. The drivers for remediating the pits are; historical records that indicate hazardous materials may have been disposed of in the pits; ground water contamination down gradient of the pits; a test excavation of one of the glass holes that unearthed laboratory glass bottles with unidentified liquids still contained; and the fact that BNL rests atop an EPA designated sole-source aquifer. The specific site chosen for this demonstration was pit G-11. The requirements that lead to choosing this pit were; a well characterized pit and a relatively isolated pit where our construction operations would not impact on adjacent pits. The glass holes area, including pit G-11, was comprehensively surveyed using a suite of geophysical techniques (e.g., EM-31, EM-61, GPR). Prior to stabilizing the waste form a subsurface barrier was constructed to contain the entire waste pit. The pit contents were then stabilized using a cement grout applied via jet grouting. The stabilization was performed to make removal of the waste from the pit easier and safer in terms of worker exposure. The grouting process would mix and masticate the waste and grout and form a single monolithic waste form. This large monolith would then be subdivided into smaller 4 foot by 4 foot by 10-12 foot block using a demolition grout. The smaller blocks would then be easily removed from the site and disposed of in a CERCLA waste site

  12. Assessment of the heating technique as a possible ex situ detritiation method for carbon wall materials from fusion machines

    Science.gov (United States)

    Bekris, N.; Skinner, C. H.; Berndt, U.; Gentile, C. A.; Glugla, M.; Erbe, A.; Pilz, W.

    2004-08-01

    Detritiation by heat treatment of graphite or carbon fibre composite (CFC) tiles retrieved from the Tokamak Fusion Test Reactor (TFTR) was assessed using the standard and well proved technique of full combustion combined with liquid scintillation analysis. Complete carbon tiles were heated in a oven to 500 °C in air for one hour at Princeton Plasma Physics Laboratory (PPPL) and sent to Tritium Laboratory Karlsruhe (TLK) for surface and depth profile analysis. Coring/full combustion technique performed on the treated and untreated tiles, both graphite and CFC, has shown that only the tritium held close to the surface (few tens ?m) is efficiently released by baking in air while the bulk tritium is almost unaffected. Therefore, baking the tile under air, even at 500 °C, does not detritiate the bulk.

  13. Accuracy assessment of water vapour measurements from in situ and remote sensing techniques during the DEMEVAP 2011 campaign at OHP

    OpenAIRE

    Bock, O; Bosser, P.; Bourcy, T.; David, L.; Goutail, F.; Hoareau, C.; Keckhut, P.; Legain, D.; Pazmino, A.; Pelon, J.; K. Pipis; Poujol, G.; SARKISSIAN, A.; Thom, C; Tournois, G.

    2013-01-01

    The Development of Methodologies for Water Vapour Measurement (DEMEVAP) project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems. A field experiment was conducted i...

  14. THE EFFICACY OF REINFORCEMENT TECHNIQUE ON THE FLY ASH STABILIZED EXPANSIVE SOIL AS A SUBGRADE EMBANKMENT FOR HIGHWAYS

    Directory of Open Access Journals (Sweden)

    KOTESWARA RAO.D

    2011-02-01

    Full Text Available The most significant factor that influencing the design thickness of a flexible pavement overlay is rebound deformation from repeated load application and subgrade support values . It is essential to stabilize and reinforce the poor soils to bear the traffic intensity or truck loading. Different types of materials are provided with stabilization techniques to achieve suitable performance and to reduce maintenance costs and also to provide required service life for the subgrade embankments. In the present study, the effect of geo-textile as a reinforcement in the sub grade embankment is verified by conducting cyclic plate load tests. Locally available soil is mixed with optimum of fly ash and then this mixer is stabilized with optimum of CaCl2 for the construction of sub grade embankment with and with out reinforcement. Compaction properties and C.B.R values are determined for the locally available soil and categorized as CH soil as per IS classification, fly ash, fly ash - CaCl2 mix with the CH soil. The introduction of geo-textile has been reduced the deformation and increased the load carrying capacity as was revealed by cyclic plate load tests.

  15. Control law synthesis and stability robustness improvement using constrained optimization techniques

    Science.gov (United States)

    Mukhopadhyay, Vivekananda

    1990-01-01

    The present generic optimization procedure for a continuous or discrete control law (of arbitrary order), which will be applicable to a multiinput-multioutput system, is upon constraining used to satisfy conflicting design requirements on the mean-square responses and stability robustness at the plant input and output. The synthesis procedure is especially suitable for flexible airframes and large space structures modeled by a high-order state-space system of equations. Analytical expressions are obtained for the gradients of the cost function, together with design constraints on the mean-square response and minimum singular value.

  16. Simple technique to measure toric intraocular lens alignment and stability using a smartphone.

    Science.gov (United States)

    Teichman, Joshua C; Baig, Kashif; Ahmed, Iqbal Ike K

    2014-12-01

    Toric intraocular lenses (IOLs) are commonly implanted to correct corneal astigmatism at the time of cataract surgery. Their use requires preoperative calculation of the axis of implantation and postoperative measurement to determine whether the IOL has been implanted with the proper orientation. Moreover, toric IOL alignment stability over time is important for the patient and for the longitudinal evaluation of toric IOLs. We present a simple, inexpensive, and precise method to measure the toric IOL axis using a camera-enabled cellular phone (iPhone 5S) and computer software (ImageJ). PMID:25316617

  17. In situ object counting system (ISOCSi3TM) technique: A cost-effective tool for NDA verification in IAEA Safeguards

    International Nuclear Information System (INIS)

    Nuclear material measurements using the ISOCS technique are playing an increasing role in IAEA verification activities. The ISOCS capabilities include: a high sensitivity to the presence of U and Pu; the ability to detect very small amounts of material; and the ability to measure items of different shapes and sizes. In addition, the numerical absolute efficiency calibration of a germanium detector used in the technique does not require any calibration standards or reference materials. The ISOCS modelling software performs an absolute efficiency calibration for items with various container shapes, container wall materials, material compositions, material fill-heights, U/Pu weight fractions and even heterogeneously distributed emitting materials. In a number of cases, some key parameters, such as the matrix density and U/Pu weight fraction, can be determined in addition to the emitting material mass and isotopic composition. These capabilities provide a verification solution suitable for a majority of cases where quantitative and isotopic analysis should be performed. Taking into account these advantages, the technique becomes a cost-effective solution for nuclear material non-destructive assay (NDA) verification. At present, the IAEA uses the ISOCS for a wide range of applications including the quantitative analysis of U scrap materials, U/Pu contaminated solid wastes, U fuel elements, U hold-up materials. Additionally, the ISOCS is also applied to some specific verifiCS is also applied to some specific verification cases such as the measurement of PuBe neutron sources and the quantification of fission products in solid wastes. In reprocessing facilities with U/Pu waste compaction or facilities with item re-batching, the continuity-of-knowledge can be assured by applying either video surveillance systems together with seals (requiring attaching/detaching and verification activities for each seal) or verification of operator declarations using quantitative measurements for items selected on a random basis. In some cases, the first option is too expensive and places a high demand on inspector and operator time. Quantitative NDA based on the ISOCS technique verifies these materials and significantly decreases the resources required for assuring the continuity-of-knowledge. (authors)

  18. Advanced Techniques for In-Situ Monitoring of Phase Transformations During Welding Using Synchrotron-Based X-Ray Diffraction

    International Nuclear Information System (INIS)

    Understanding the evolution of microstructure in welds is an important goal of welding research because of the strong correlation between weld microstructure and weld properties. To achieve this goal it is important to develop a quantitative measure of phase transformations encountered during welding in order to ultimately develop methods for predicting weld microstructures from the characteristics of the welding process. To aid in this effort, synchrotron radiation methods have been developed at Lawrence Livermore National Laboratory (LLNL) for direct observation of microstructure evolution during welding. Using intense, highly collimated synchrotron radiation, the atomic structure of the weld heat affected and fusion zones can be probed in real time. Two synchrotron-based techniques, known as spatially resolved (SRXRD) and time resolved (TRXRD) x-ray diffraction, have been developed for these investigations. These techniques have now been used to investigate welding induced phase transformations in titanium alloys, low alloy steels, and stainless steel alloys. This paper will provide a brief overview of these methods and will discuss microstructural evolution during the welding of low carbon (AISI 1005) and medium carbon (AISI 1045) steels where the different levels of carbon influence the evolution of microstructures during welding

  19. In-plane strain measurements on a microscopic scale by coupling digital image correlation and an in situ SEM technique

    International Nuclear Information System (INIS)

    The purpose of this paper is to present a method based on the correlation of digital images obtained on a microscopic scale. A specific grainy pattern has been developed. The use of the scanning electron microscopy (SEM) allowed the determination of full-field 2D displacements on an object surface with a spatial resolution of about 1 ?m. Validation tests were performed in order to quantify performances and limits of this method. An example of its application is presented for a Ti-6Al-4V titanium alloy. Results show that it is possible to obtain in-plane displacement values on the object surface with efficient spatial resolution and accuracy. Thus, such a technique can be used to highlight on a relevant scale the role of the microstructure in material deformation processes

  20. A comparison of multiple regression and neural network techniques for mapping in situ pCO2 data

    International Nuclear Information System (INIS)

    Using about 138,000 measurements of surface pCO2 in the Atlantic subpolar gyre (50-70 deg N, 60-10 deg W) during 1995-1997, we compare two methods of interpolation in space and time: a monthly distribution of surface pCO2 constructed using multiple linear regressions on position and temperature, and a self-organizing neural network approach. Both methods confirm characteristics of the region found in previous work, i.e. the subpolar gyre is a sink for atmospheric CO2 throughout the year, and exhibits a strong seasonal variability with the highest undersaturations occurring in spring and summer due to biological activity. As an annual average the surface pCO2 is higher than estimates based on available syntheses of surface pCO2. This supports earlier suggestions that the sink of CO2 in the Atlantic subpolar gyre has decreased over the last decade instead of increasing as previously assumed. The neural network is able to capture a more complex distribution than can be well represented by linear regressions, but both techniques agree relatively well on the average values of pCO2 and derived fluxes. However, when both techniques are used with a subset of the data, the neural network predicts the remaining data to a much better accuracy than the regressions, with a residual standard deviation ranging from 3 to 11 ?atm. The subpolar gyre is a net sink of CO2 of 0.13 Gt-C/yr using the mu2 of 0.13 Gt-C/yr using the multiple linear regressions and 0.15 Gt-C/yr using the neural network, on average between 1995 and 1997. Both calculations were made with the NCEP monthly wind speeds converted to 10 m height and averaged between 1995 and 1997, and using the gas exchange coefficient of Wanninkhof

  1. Clasificación molecular del cáncer de mama, obtenida a través de la técnica de hibridación in situ cromogénica (CISH) / Molecular classification of breast cancer patients obtained through the technique of chromogenic in situ hybridization (CISH)

    Scientific Electronic Library Online (English)

    Ángel, Fernández; Aldo, Reigosa.

    2013-12-01

    Full Text Available El cáncer de mama es una enfermedad heterogénea compuesta de un número creciente de subtipos biológicos, con una sustancial variabilidad en la evolución de la enfermedad dentro de cada categoría. El objetivo del presente trabajo fue clasificar las muestras objeto a estudio de acuerdo a las clases mo [...] leculares de carcinoma de mama: luminal A, luminal B, HER2 y triple negativo, considerando el estado de amplificación de HER2 obtenido a través de la técnica de hibridación in situ cromogénica (CISH). La muestra estuvo constituida por 200 biopsias fijadas en formol al 10%, procesadas por las técnicas habituales hasta la inclusión en parafina, correspondientes a pacientes diagnosticadas con carcinoma ductal infiltrante de la mama, procedentes de consulta privada y del Instituto de Oncología “Dr. Miguel Pérez Carreño”, con estudio inmunohistoquímico (IHQ) para receptores hormonales y HER2 realizado en el Hospital Metropolitano del Norte de Valencia, Venezuela. La clasificación molecular de los tumores de las pacientes, considerando la expresión de los Receptores de Estrógeno (RE) y Receptores de Progesterona (RP) a través de IHQ y la amplificación de HER2 por CISH, permitió agrupar en las diferentes clases moleculares los casos calificados inicialmente como desconocidos, debido a que tenían un resultado indeterminado (2+) para la expresión de HER2 por IHQ; asimismo, esta clasificación ocasionó que algunos casos considerados inicialmente en una clase molecular pasaron a otra clase, posterior a la revaloración del estado de HER2 a través de CISH. Abstract in english Breast cancer is a heterogeneous disease composed of a growing number of biological subtypes, with substantial variability of the disease progression within each category. The aim of this research was to classify the samples object of study according to the molecular classes of breast cancer: lumina [...] l A, luminal B, HER2 and triple negative, as a result of the state of HER2 amplification obtained by the technique of chromogenic in situ hybridization (CISH). The sample consisted of 200 biopsies fixed in 10% formalin, processed by standard techniques up to paraffin embedding, corresponding to patients diagnosed with invasive ductal carcinoma of the breast. These biopsies were obtained from patients from private practice and the Institute of Oncology “Dr. Miguel Pérez Carreño", for immunohistochemistry (IHC) of hormone receptors and HER2 made in the Hospital Metropolitano del Norte, Valencia, Venezuela. The molecular classification of the patient’s tumors considering the expression of estrogen and progesterone receptors by IHC and HER2 amplification by CISH, allowed those cases originally classified as unknown, since they had an indeterminate (2+) outcome for HER2 expression by IHC, to be grouped into the different molecular classes. Also, this classification permitted that some cases, initially considered as belonging to a molecular class, were assigned to another class, after the revaluation of the HER2 status by CISH.

  2. Studies of MHD stability using data mining technique in helical plasmas

    International Nuclear Information System (INIS)

    Data mining techniques, which automatically extract useful knowledge from large datasets, are applied to multichannel magnetic probe signals of several helical plasmas in order to identify and classify MHD instabilities in helical plasmas. This method is useful to find new MHD instabilities as well as previously identified ones. Moreover, registering the results obtained from data mining in a database allows us to investigate the characteristics of MHD instabilities with parameter studies. We introduce the data mining technique consisted of pre-processing, clustering and visualizations using results from helical plasmas in H-1 and Heliotron J. We were successfully able to classify the MHD instabilities using the criterion of phase differences of each magnetic probe and identify them as energetic-ion-driven MHD instabilities using parameter study in Heliotron J plasmas. (author)

  3. A technique coupling the analyte electrodeposition followed by in-situ stripping with electrothermal atomic absorption spectrometry for analysis of samples with high NaCl contents

    Energy Technology Data Exchange (ETDEWEB)

    Cansky, Zdenek [Charles University in Prague, Faculty of sciences, Department of Analytical Chemistry, Albertov 2030, Prague 2 (Czech Republic); Rychlovsky, Petr [Charles University in Prague, Faculty of sciences, Department of Analytical Chemistry, Albertov 2030, Prague 2 (Czech Republic)], E-mail: rychlov@natur.cuni.cz; Petrova, Zuzana [Charles University in Prague, Faculty of sciences, Department of Analytical Chemistry, Albertov 2030, Prague 2 (Czech Republic); Matousek, J.P. [School of Chemical Sciences, University of New South Wales, UNSW Sydney, NSW 2052 (Australia)

    2007-03-15

    A technique coupling the analyte electrodeposition followed by in-situ stripping with electrothermal atomic absorption spectrometry has been developed for determination of lead and cadmium in samples with high salt contents. To separate the analyte from the sample matrix, the analyte was in-situ quantitatively electrodeposited on a platinum sampling capillary serving as the cathode (sample volume, 20 {mu}L). The spent electrolyte containing the sample matrix was then withdrawn, the capillary with the analyte deposited was washed with deionized water and the analyte was stripped into a chemically simple electrolyte (5 g/L NH{sub 4}H{sub 2}PO{sub 4}) by reversing the polarity of the electrodeposition circuit. Electrothermal atomization using a suitable optimized temperature program followed. A fully automated manifold was designed for this coupled technique and the appropriate control software was developed. The operating conditions for determination of Pb and Cd in samples with high contents of inorganic salts were optimized, the determination was characterized by principal analytical parameters and its applicability was verified on analyses of urine reference samples. The absolute limits of detection for lead and cadmium (3{sigma} criterion) in a sample containing 30 g/L NaCl were 8.5 pg and 2.3 pg, respectively (peak absorbance) and the RSD values amounted to 1.6% and 1.9% for lead (at the 40 ng mL{sup -1} level) and cadmium (at the 4.0 ng mL{sup -1} level), respectively. These values (and also the measuring sensitivity) are superior to the results attained in conventional electrothermal atomic absorption spectrometric determination of Pb and Cd in pure solutions (5 g/L NH{sub 4}H{sub 2}PO{sub 4}). The sensitivity of the Pb and Cd determination is not affected by the NaCl concentration up to a value of 100 g/L, demonstrating an efficient matrix removal during the electrodeposition step.

  4. A simplified technique for in situ excision of cornea and evisceration of retinal tissue from human ocular globe.

    Science.gov (United States)

    Parekh, Mohit; Ferrari, Stefano; Di Iorio, Enzo; Barbaro, Vanessa; Camposampiero, Davide; Karali, Marianthi; Ponzin, Diego; Salvalaio, Gianni

    2012-01-01

    Enucleation is the process of retrieving the ocular globe from a cadaveric donor leaving the rest of the globe undisturbed. Excision refers to the retrieval of ocular tissues, especially cornea, by cutting it separate from the ocular globe. Evisceration is the process of removing the internal organs referred here as retina. The ocular globe consists of the cornea, the sclera, the vitreous body, the lens, the iris, the retina, the choroid, muscles etc (Suppl. Figure 1). When a patient is suffering from corneal damage, the cornea needs to be removed and a healthy one must be transplanted by keratoplastic surgeries. Genetic disorders or defects in retinal function can compromise vision. Human ocular globes can be used for various surgical procedures such as eye banking, transplantation of human cornea or sclera and research on ocular tissues. However, there is little information available on human corneal and retinal excision, probably due to the limited accessibility to human tissues. Most of the studies describing similar procedures are performed on animal models. Research scientists rely on the availability of properly dissected and well-conserved ocular tissues in order to extend the knowledge on human eye development, homeostasis and function. As we receive high amount of ocular globes out of which approximately 40% (Table 1) of them are used for research purposes, we are able to perform huge amount of experiments on these tissues, defining techniques to excise and preserve them regularly. The cornea is an avascular tissue which enables the transmission of light onto the retina and for this purpose should always maintain a good degree of transparency. Within the cornea, the limbus region, which is a reservoir of the stem cells, helps the reconstruction of epithelial cells and restricts the overgrowth of the conjunctiva maintaining corneal transparency and clarity. The size and thickness of the cornea are critical for clear vision, as changes in either of them could lead to distracted, unclear vision. The cornea comprises of 5 layers; a) epithelium, b) Bowman's layer, c) stroma, d) Descemet's membrane and e) endothelium. All layers should function properly to ensure clear vision(4,5,6). The choroid is the intermediate tunic between the sclera and retina, bounded on the interior by the Bruch's membrane and is responsible for blood flow in the eye. The choroid also helps to regulate the temperature and supplies nourishment to the outer layers of the retina(5,6). The retina is a layer of nervous tissue that covers the back of the ocular globe (Suppl. Figure 1) and consists of two parts: a photoreceptive part and a non-receptive part. The retina helps to receive the light from the cornea and lens and converts it into the chemical energy eventually transmitted to the brain with help of the optic nerve(5,6). The aim of this paper is to provide a protocol for the dissection of corneal and retinal tissues from human ocular globes. Avoiding cross-contamination with adjacent tissues and preserving RNA integrity is of fundamental importance as such tissues are indispensable for research purposes aimed at (i) characterizing the transcriptome of the ocular tissues, (ii) isolating stem cells for regenerative medicine projects, and (iii) evaluating histological differences between tissues from normal/affected subjects. In this paper we describe the technique we currently use to remove the cornea, the choroid and retinal tissues from an ocular globe. Here we provide a detailed protocol for the dissection of the human ocular globe and the excision of corneal and retinal tissues. The accompanying video will help researchers to learn an appropriate technique for the retrieval of precious human tissues which are difficult to find regularly. PMID:22733120

  5. A Technique to Eliminate External Transport Barriers and Stabilize Fiscal Instabilities

    Science.gov (United States)

    Heeter, Robert F.

    1997-11-01

    The case is made for a coordinated national effort to diffuse plasma science knowledge to the public. Like earlier "fiscal instabilities" in plasma research, the 1995-7 magnetic fusion budget disruption can be attributed to a lack of public awareness about the value of science research, as reflected in the attitude of Congress. Magnetic fusion researchers now create "internal transport barriers" to reduce plasma heat loss, but observations also reveal a problematic "external transport barrier" in all of plasma science - the inadequate diffusion of knowledge beyond the scientists. Public funding creates scientific knowledge for the public good, and now the public cares - and deserves to know - what it pays for. Eliminating the external transport barrier should suppress the fiscal instability: theory predicts that funding should stabilize - or even increase - if the value of plasma science is understood by the bulk of Congress' members before they're elected, rather than just a small population of patrons energetically lobbied in office. If the public understands the value of plasma research, Congress will too. But plasmas are poorly represented in both contemporary classrooms and public perception. To reach the "Lawson Criterion" for ignition of public understanding, we should reach out to the public and to educators nationwide. Education and outreach activities are, and ought to be, part of the professional life of a plasma scientist. Our current activities consist largely of teaching our own classes, writing papers, lobbying Congress, giving lab tours, making Web pages, and promoting education locally; these have been useful, but insufficient. Now we must do better. To stabilize fiscal instabilities for good, we should restructure not only our research programs, but our sense of what it means to be a scientist. We should coordinate our education and outreach activities on a national scale, maximizing impact while minimizing cost in time, labor, and money. To this end our existing education and outreach activities are evaluated, and new activities are suggested. A coordinated education and outreach effort is sketched, involving the DPP, the DOE, labs and universities, and everyone from our senior management to our enthusiastic students. A modification of the professional physics pipeline is proposed to encourage recruitment, retention, and development of scientists who are not only sources of new knowledge, but who also conduct, convect, and radiate their knowledge to others. The implantation of plasma topics and examples into the educational system is advocated, not to make learning harder, but so plasmas are actually treated as the fourth state of matter. If younger scientists adopt this "Coordinated Civic Science" professional spirit, and older scientists and program leaders support it, we should succeed.

  6. Applications of a new magnetic monitoring technique to in situ evaluation of fatigue damage in ferrous components

    International Nuclear Information System (INIS)

    This project consisted of research into the use of magnetic inspection methods for the estimation of fatigue life of nuclear pressure vessel steel. Estimating the mechanical and magnetic properties of ferromagnetic materials are closely interrelated, therefore, measurements of magnetic properties could be used to monitor the evolution of fatigue damage in specimens subjected to cyclic loading. Results have shown that is possible to monitor the fatigue damage nondestructively by magnetic techniques. For example, in load-controlled high-cycle fatigue tests, it has been found that the plastic strain and coercivity accumulate logarithmically during the fatigue process. Thus a quantitative relationship between coercivity and the number of fatigue cycles could be established based on two empirical coefficients, which can be determined from the test conditions and material properties. Also it was found that prediction of the onset of fatigue failure in steels was possible under certain conditions. In strain-controlled low cycle fatigue, critical changes in Barkhausen emissions, coercivity and hysteresis loss occurred in the last ten to twenty percent of fatigue life

  7. Improving the mechanical properties of polyamide 6-nanosilica nanocomposites by combining masterbatch technique with in situ polymerization

    Scientific Electronic Library Online (English)

    Qijie, Xu; Xiaohong, Li; Fangfei, Chen; Zhijun, Zhang.

    1218-12-01

    Full Text Available Um masterbatch (MA) reativo de poliamida 6 (PA6)/SiO2 contendo 20% (fração de massa) de nano-SiO2 foi preparado. Posteriormente, o MA reativo preparado foi usado como carga no preparo de nanocompósitos PA6/SiO2 (RA). A estrutura do RA foi analisada por espectrometria no infravermelho por transformad [...] a de Fourier (FTIR), microscopia eletrônica de transmissão (TEM), difratometria de raios X (XRD), microscopia eletrônica de varredura (SEM) e microscopia óptica de luz polarizada (POM). A estabilidade térmica e o comportamento de cristalização do RA foram avaliados por análise termogravimétrica (TGA) e calorimetria exploratória diferencial (DSC). OS resultados indicaram que as cadeias moleculares de PA6 estavam ancoradas na superfície do nano-SiO2 através de ligações químicas entre a superfície de grupos amino do nano-SiO2 e do monômero da ?-caprolactama ou pré-polímero da PA6. Como resultado, uma camada interfacial flexível foi formada, melhorando a compatibilidade do nano-SiO2 com a matriz de PA6. Além disso, o efeito no nano-SiO2 apresentou melhoras nas propriedades mecânicas do RA. Devido ao efeito de impedimento de movimento das cadeias moleculares da PA6 pelas partículas de nano-SiO2, o tamanho da esfera cristalina de PA6 foi menor e sua forma cristalina também foi afetada. A massa molar da matriz de PA6 tende a decair gradualmente com o aumento do conteúdo nano-SiO2. Abstract in english A reactive polyamide 6 (PA6)/SiO2 masterbatch (MA) containing 20% (mass fraction) of nano-SiO2 was prepared readily. Furthermore, the as-prepared reactive MA was used as a filler to prepare PA6/SiO2 nanocomposites (RA). The structure of RA was analyzed by means of Fourier transform infrared spectrop [...] hotometry (FTIR), transmission electron microscopy (TEM), powder X-ray diffractometry (XRD), scanning electronic microscopy (SEM) and polarizing microscopy (POM). Thermal stability and crystallization behaviors of RA were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Findings indicated that the PA6 molecular chains were anchored on the surface of nano-SiO2 through chemical bonding between the surface amino groups of nano-SiO2 and ?-caprolactam monomer or prepolymer of PA6. As a result, a flexible interfacial layer was formed, thereby improving the compatibility of nano-SiO2 with PA6 matrix. Moreover, the enhancement effect of nano-SiO2 led to the improved mechanical properties of RA. Besides, due to the hindering effect of nano-SiO2 particles to the movement of PA6 molecular chains, the size of the PA6 spherocrystal was smaller, and its crystalline form was also affected. Furthermore, the molecular weight of the PA6 matrix tended to decrease gradually with increasing nano-SiO2 content.

  8. Assessing the stability of soil organic matter by fractionation and 13C isotope techniques

    Science.gov (United States)

    Larionova, A. A.; Zolotareva, B. N.; Kvitkina, A. K.; Evdokimov, I. V.; Bykhovets, S. S.; Stulin, A. F.; Kuzyakov, Ya. V.; Kudeyarov, V. N.

    2015-02-01

    Carbon pools of different stabilities have been separated from the soil organic matter of agrochernozem and agrogray soil samples. The work has been based on the studies of the natural abundance of the carbon isotope composition by C3-C4 transition using the biokinetic, size-density, and chemical fractionation (6 M HCl hydrolysis) methods. The most stable pools with the minimum content of new carbon have been identified by particle-size and chemical fractionation. The content of carbon in the fine fractions has been found to be close to that in the nonhydrolyzable residue. This pool makes up 65 and 48% of Corg in the agrochernozems and agrogray soils, respectively. The combination of the biokinetic approach with particle-size fractionation or 6 M HCl hydrolysis has allowed assessing the size of the medium-stable organic carbon pool with a turnover time of several years to several decades. The organic matter pool with this turnover rate is usually identified from the variation in the 13C abundance by C3-C4 transition. In the agrochernozems and agrogray soils, the medium-stable carbon pool makes up 35 and 46% of Corg, respectively. The isotope indication may be replaced by a nonisotope method to significantly expand the study of the inert and mediumstable organic matter pools in the geographical aspect, but this requires a comparative analysis of particle-size and chemical fractionation data for all Russian soils.

  9. Thermodynamic stability of Nd2TeO6 by transpiration technique

    International Nuclear Information System (INIS)

    Vapour pressure of TeO2(g) over Nd2TeO6/Nd2O3 was measured by the transpiration technique over the temperature range 1408 -1541K, using a thermal analyzer. The measured vapour pressures could be represented by the expression log p (Pa) (± 0.04) = 17.39- 24559/ T(K). From the measured partial pressure of TeO2 (g) , the standard Gibbs energy of formation of Nd2TeO6 was determined to be, DGfo (Nd2TeO6, s) (± 5.0 kJ mol-l) -2358.5+ 0.62723 T (K)

  10. Improved oral absorption and chemical stability of everolimus via preparation of solid dispersion using solvent wetting technique.

    Science.gov (United States)

    Jang, Sun Woo; Kang, Myung Joo

    2014-10-01

    The aim of this study was to improve the physicochemical properties and oral absorption of poorly water-soluble everolimus via preparation of a solid dispersion (SD) system using a solvent wetting (SW) technique. The physicochemical properties, drug release profile, and bioavailability of SD prepared by SW process were also compared to SD prepared by the conventional co-precipitation method. Solid state characterizations using scanning electron microscopy, particle size analysis and X-ray powder diffraction indicated that drug homogeneously dispersed and existed in an amorphous state within the intact polymeric carrier. Whereas, a film-like mass was obtained by a co-precipitation method and further pulverization step was needed for tabletization. The drug release from the SD tablet prepared by SW process at a ratio of drug to hydroxypropyl methylcellulose of 1:15 was markedly higher than the drug alone and equivalent to the marketed product (Afinitor(®), Novartis Pharmaceuticals), a SD tablet prepared by co-precipitation method, archiving over 75% the drug release after 30 min. At the accelerated (40°C/75% R.H.) and stress (80°C) stability tests, the novel formula was more stable than drug powder and provided comparable drug stability with the commercially available product, which contains a potentially risky antioxidant, butylated hydroxyl toluene. The pharmacokinetic parameters after single oral administration in beagles showed no significant difference (P>0.01) between the novel SD-based tablet and the marketed product. The results of this study, therefore, suggest that the novel SD system prepared by the solvent wetting process may be a promising approach for improving the physicochemical stability and oral absorption of the sirolimus derivatives. PMID:25003829

  11. Surgical technique: hemi-extensor carpi radialis brevis tenodesis for stabilizing the midcarpal joint in Ehlers-Danlos syndrome.

    Science.gov (United States)

    Krijgh, David D; Harley, Oliver J; Hovius, Steven E; Coert, J Henk; Walbeehm, Erik T

    2014-10-01

    Patients with the hypermobility type of Ehlers-Danlos (EDS-HT) often complain of wrist pain, usually originating from subluxations. As a result of the laxity, wrist function in these patients can be highly limited. This paper presents a surgical technique that stabilizes the lunocapitate joint with the use of an extensor carpi radialis brevis strip. Five patients with confirmed EDS-HT were treated with an extensor carpi radialis brevis tenodesis for their midcarpal instability. Two patients presented with complications following surgery, one major and one minor. This paper presents a potentially satisfactory surgical solution to recurrent midcarpal instability in EDS-HT patients and demonstrates that the use of an autologous tendon might be feasible in spite of a background of abnormal collagen metabolism. PMID:25194773

  12. Chemiluminescence - a useful technique for characterizing the stability and forecasting the lifetime of polymer materials for nuclear applications

    International Nuclear Information System (INIS)

    The chemiluminescence (CL) mechanism is tightly related to the polymer oxidation mechanism both of them proceeding by means of peroxidic species (free radicals) and hydroperoxides of the polymer. The CL emission is strongly influenced by the stabilizing antioxidants, the efficiency and concentration of which being correlated with the CL signal.. This paper presents the mechanism of CL emission, the methods of materials characterization of polymers based on polyethylene and additives, evaluation of the materials lifetime as well as recent experimental examples regarding the characterization of the efficiency of some stabilizing agents (antirad agents of the type of radical captors or energy deactivators). Also the study of some synergic effects, and the diagnosis of degradation of some cable isolations exposed to electrical or radiation fields. The results obtained were correlated with those obtained by other techniques, namely, IR, UV spectroscopy, thermal analysis, electrical tests, oxygen absorption, chemical and mechanical tests, which demonstrated the high sensitivity of the method. Since the CL tests need only small material amounts, of the order of 2-4 mg, the method can be used for characterization of raw materials and products of fabrication as well as in the diagnosing the degradation of samples exposed to service-like conditions to evaluate the lifetime expectation or the remaining service time

  13. Effect of heat treatment on the structure and stability of multiwalled carbon nanotubes produced by catalytic chemical vapor deposition technique

    International Nuclear Information System (INIS)

    Highlights: ? Post synthesis heat treatment of the nanotubes introduces long range ordering of the layer planes. ? Increased purity and thermal stability of the tubes has been achieved by the removal of catalyst impurity. ? Development of the sword-in-scabbard structure in the multiwalled carbon nanotubes due to heat treatment. ? Improved performance (electrical and mechanical) of the polymer composites using heat treated carbon nanotubes as reinforcement. - Abstract: The multiwalled carbon nanotubes (MWCNTs) produced by catalytic chemical vapor deposition (CCVD) route were heat treated to 2500 °C to improve the structure, morphology and purity level. The process has lead to substantial reduction in the catalytic impurity along with an improved thermal stability and degree of graphitization of these tubes that can possibly lead to its better utilization in various applications. The structural changes following heat treatment have been correlated using various characterization techniques such as Raman spectroscopy, X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, thermo gravimetric analysis and electron paramagnetic resonance spectroscopy. The electrical and mechanical properties of the polymer composites prepared with heat treated MWCNT show improved properties over the one prepared by as produced MWCNT.

  14. Accuracy assessment of water vapour measurements from in-situ and remote sensing techniques during the DEMEVAP 2011 campaign

    Science.gov (United States)

    BOCK, Olivier; Bosser, Pierre; David, Leslie; Thom, Christian; Pelon, Jacques; Hoareau, Christophe; Keckhut, Philippe; Sarkissian, Alain; Pazmino, Andrea; Goutail, Florence; Legain, Dominique; Tzanos, Diane; Bourcy, Thomas; Poujol, Guillaume; Tournois, Guy

    2014-05-01

    The Development of Methodologies for Water Vapour Measurement (DEMEVAP) project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems. A field experiment was conducted in September-October 2011 at Observatoire de Haute Provence (OHP). Two Raman lidars (IGN mobile lidar and OHP NDACC lidar), a stellar spectrometer (SOPHIE), a differential absorption spectrometer (SAOZ), a sun photometer (AERONET), 5 GPS receivers and 4 types of radiosondes (Vaisala RS92, MODEM M2K2-DC and M10, and Meteolabor Snow-White) participated in the campaign. A total of 26 balloons with multiple radiosondes were flown during 16 clear nights. This paper presents preliminary findings from the analysis of all these datasets. Several classical Raman lidar calibration methods are evaluated which use either Vaisala RS92 measurements, point capacitive humidity measurements, or GPS integrated water vapour (IWV) measurements. A novel method proposed by Bosser et al. (2010) is also tested. It consists in calibrating the lidar measurements during the GPS data processing. The methods achieve a repeatability of 4-5 %. Changes in calibration factor of IGN Raman lidar are evidenced which are attributed to frequent optical re-alignments. When modelling and correcting the changes as a linear function of time, the precision of the calibration factors improves to 2-3 %. However, the variations in the calibration factor, and hence the absolute accuracy, between methods and types of reference data remain at the level of 7 %. The intercomparison of radiosonde measurements shows good agreement between RS92 and Snow-White measurements up to 12 km. An overall dry bias is found in the measurements from both MODEM radiosondes. Investigation of situations with low RH values (RS92 due to a saturation of the Peltier device. However, on other occasions, a dry bias is found in RS92, instead. On average, both RS92 and Snow-White measurements show a slight moist bias at night-time compared to GPS IWV, while the MODEM measurements show a large dry bias. The IWV measurements from SOPHIE (night-time) and SAOZ (daytime) spectrometers, AERONET photometer (daytime) and calibrated Raman lidar (night-time) showed excellent agreement with the GPS IWV measurements.

  15. Accuracy assessment of water vapour measurements from in situ and remote sensing techniques during the DEMEVAP 2011 campaign at OHP

    Science.gov (United States)

    Bock, O.; Bosser, P.; Bourcy, T.; David, L.; Goutail, F.; Hoareau, C.; Keckhut, P.; Legain, D.; Pazmino, A.; Pelon, J.; Pipis, K.; Poujol, G.; Sarkissian, A.; Thom, C.; Tournois, G.; Tzanos, D.

    2013-10-01

    The Development of Methodologies for Water Vapour Measurement (DEMEVAP) project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems. A field experiment was conducted in September-October 2011 at Observatoire de Haute-Provence (OHP). Two Raman lidars (IGN mobile lidar and OHP NDACC lidar), a stellar spectrometer (SOPHIE), a differential absorption spectrometer (SAOZ), a sun photometer (AERONET), 5 GPS receivers and 4 types of radiosondes (Vaisala RS92, MODEM M2K2-DC and M10, and Meteolabor Snow White) participated in the campaign. A total of 26 balloons with multiple radiosondes were flown during 16 clear nights. This paper presents preliminary findings from the analysis of all these data sets. Several classical Raman lidar calibration methods are evaluated which use either Vaisala RS92 measurements, point capacitive humidity measurements, or GPS integrated water vapour (IWV) measurements. A novel method proposed by Bosser et al. (2010) is also tested. It consists in calibrating the lidar measurements during the GPS data processing. The methods achieve a repeatability of 4-5%. Changes in the calibration factor of IGN Raman lidar are evidenced which are attributed to frequent optical re-alignments. When modelling and correcting the changes as a linear function of time, the precision of the calibration factors improves to 2-3%. However, the variations in the calibration factor, and hence the absolute accuracy, between methods and types of reference data remain at the level of 7%. The intercomparison of radiosonde measurements shows good agreement between RS92 and Snow White measurements up to 12 km. An overall dry bias is found in the measurements from both MODEM radiosondes. Investigation of situations with low RH values (RS92 due to a saturation of the Peltier device. However, on other occasions, a dry bias is found in RS92, instead. On average, both RS92 and Snow White measurements show a slight moist bias at night-time compared to GPS IWV, while the MODEM measurements show a large dry bias. The IWV measurements from SOPHIE (night-time) and SAOZ (daytime) spectrometers, AERONET photometer (daytime) and calibrated Raman lidar (night-time) showed excellent agreement with the GPS IWV measurements.

  16. Accuracy assessment of water vapour measurements from in situ and remote sensing techniques during the DEMEVAP 2011 campaign at OHP

    Directory of Open Access Journals (Sweden)

    O. Bock

    2013-10-01

    Full Text Available The Development of Methodologies for Water Vapour Measurement (DEMEVAP project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems. A field experiment was conducted in September–October 2011 at Observatoire de Haute-Provence (OHP. Two Raman lidars (IGN mobile lidar and OHP NDACC lidar, a stellar spectrometer (SOPHIE, a differential absorption spectrometer (SAOZ, a sun photometer (AERONET, 5 GPS receivers and 4 types of radiosondes (Vaisala RS92, MODEM M2K2-DC and M10, and Meteolabor Snow White participated in the campaign. A total of 26 balloons with multiple radiosondes were flown during 16 clear nights. This paper presents preliminary findings from the analysis of all these data sets. Several classical Raman lidar calibration methods are evaluated which use either Vaisala RS92 measurements, point capacitive humidity measurements, or GPS integrated water vapour (IWV measurements. A novel method proposed by Bosser et al. (2010 is also tested. It consists in calibrating the lidar measurements during the GPS data processing. The methods achieve a repeatability of 4–5%. Changes in the calibration factor of IGN Raman lidar are evidenced which are attributed to frequent optical re-alignments. When modelling and correcting the changes as a linear function of time, the precision of the calibration factors improves to 2–3%. However, the variations in the calibration factor, and hence the absolute accuracy, between methods and types of reference data remain at the level of 7%. The intercomparison of radiosonde measurements shows good agreement between RS92 and Snow White measurements up to 12 km. An overall dry bias is found in the measurements from both MODEM radiosondes. Investigation of situations with low RH values (< 10%RH in the lower and middle troposphere reveals, on occasion, a lower RH detection limit in the Snow White measurements compared to RS92 due to a saturation of the Peltier device. However, on other occasions, a dry bias is found in RS92, instead. On average, both RS92 and Snow White measurements show a slight moist bias at night-time compared to GPS IWV, while the MODEM measurements show a large dry bias. The IWV measurements from SOPHIE (night-time and SAOZ (daytime spectrometers, AERONET photometer (daytime and calibrated Raman lidar (night-time showed excellent agreement with the GPS IWV measurements.

  17. The modified "Wunderer" osteotomy for stabilization of the cleft-premaxilla--a new operative technique.

    Science.gov (United States)

    Steinhäuser, Emil W

    2014-07-01

    The operative closure of bilateral cleft lip and palate is a difficult procedure that requires in most cases secondary corrections. Besides aesthetic improvements of lip and nose also the rehabilitation of the teeth, in particular of the maxillary arch is important for the improvement of the chewing function and also for the well being of the patient. One of the most disturbing factors for the construction of any type of prosthetic devices, like removable denture, fixed bridge or dental implants is the mobility and often also malposition of the premaxilla. This problem can only be solved by the insertion of bone grafts into the bilateral gaps of the anterior maxillary arch. This procedure however, is difficult due to the narrowness and poor overview that complicates the closure of the nasal mucosa, which is the precondition for the success. For facilitating the operation the premaxilla is osteotomized and reflected anteriorly according to the method of Wunderer (1962). Then, after the much easier closure of the nasal mucosa the bony defects can be filled with autogenous cancellous bone and finally the oral mucosa can be closed. A preoperatively prepared palatal acrylic plate helps to protect the palatal tissue and also stabilizes the position of the premaxilla. The blood supply to the osteotomized premaxilla is secured by a sound soft tissue pedicle of the buccal muco-periosteum. The effectiveness of the blood supply of the premaxilla was examined in experimental studies by several authors. Also investigations of the growth impediments of the premaxilla and the midface revealed that early osteotomies will interfere with the development of this region. Therefore it is advisable to carry out this procedure not before the patient has reached the age of 12-14 years, which is also depending on the race and the gender of the patient. PMID:24630854

  18. Effect of particle size on the pore characterization and strength of porous cordierite-mullite ceramics prepared by a pore-forming in-situ technique

    Directory of Open Access Journals (Sweden)

    Yan W.

    2013-01-01

    Full Text Available The porous cordierite-mullite ceramics were prepared by the pore-forming in-situ technique. The characterizations of porous cordierite-mullite ceramics were determined by an X-ray diffractometer (XRD, a scanning electron microscopy (SEM, and a microscopy measured method, etc., and the effect of particle size on phase composition, pore characterization and strength were investigated. It’s found that particle size affects strongly the formations of cordierite and mullite, and then changes the pore characterization and strength. With the decrease of the particle size, the sintering temperature at which the formations of cordierite and mullite take place extremely fast decreases, the pore size distribution becomes from bi-peak mode to mono-peak mode, the porosity and the median pore size decrease but strength increases. The most opposite mode is the specimen sintered at 1400 ºC from the grinded powder with an average particle size of 10.2 ?m, which consists of cordierite, mullite and minor spinel, and has a high apparent porosity (40 %, a high compressive strength (58.4 MPa, a small median pore size (6.3 ?m and well-developed necks between particles.

  19. Two- and three-dimensional micro/nanostructure patterning of CdS-polymer nanocomposites with a laser interference technique and in situ synthesis

    International Nuclear Information System (INIS)

    Two- and three-dimensional (2D and 3D) micro/nanostructures of CdS-polymer nanocomposites have been successfully patterned, combining photopolymerization via a laser four-beam interference technique with in situ synthesis of CdS nanoparticles in the patterned polymer matrix. The morphology and optical properties of CdS nanoparticles in polymer matrices have been confirmed using TEM, XRD, FTIR, UV-vis absorption and fluorescence spectroscopy. Laser irradiation time and film thickness are certified to be the key factors for the control of the micro/nanostructures. With thickening film, the fabricated microstructures of CdS-polymer nanocomposites were dramatically changed from 2D rods to 3D networks which were composed of nanofibres, nanometre-scale walls and micrometre-scale rods. These kinds of 2D and 3D micro/nanostructures could be expected as potential applications in the development of nanotechnology, such as nanomedical systems, micro-fluidic chips, nanoreactors and micro/nanopurification or separation systems

  20. Characterization of CdTe films with in situ CdCl2 treatment grown by a simple vapor phase deposition technique

    International Nuclear Information System (INIS)

    A unique vapor phase deposition (VPD) technique was designed and built to achieve in situ CdCl2 treatment of CdTe film. The substrate temperature was 400 deg. C, and the temperature of CdTe mixture with CdCl2 source was 500 deg. C. The structural and morphological properties of CdTe have been studied as a function of wt.% CdCl2 concentration by using X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). XRD measurements show that the presence of CdCl2 vapor induces (1 1 1)-oriented growth in the CdTe film. SEM measurements have shown enhance growth of grains, in the presence of CdCl2. From AFM the roughness of the films showed a heavy dependence on CdCl2 concentration. In the presence of 4% CdCl2 concentration, the CdTe films roughness has a root mean square (rms) value of about 275 A. This value is about 831 A for the non-treated CdTe films.

  1. Structural change of Ni-Cu alloy nanowires with temperature studied by in situ X-ray absorption fine structure technique

    International Nuclear Information System (INIS)

    Ni-Cu alloy nanowire array, with uniform length and diameter, was well fabricated by using alternating current electrodeposition. Both X-ray diffraction and in situ heating extended X-ray absorption fine structure technique were employed to characterize its structural change with temperature. As expected, a weak concentration fluctuation of Ni and Cu atoms was found in the as-prepared nanowires. However, this concentration fluctuation can be easily eliminated by heating the as-prepared sample at 200 deg. C, which resulting in an approximately homogeneous Ni-Cu solid solution. From the nanostructural point of view, the serviceability temperature of Ni-Cu alloy nanowire array in magnetism could not exceed 200 deg. C. The Ni-Ni, Ni-Cu and Cu-Cu bonds were found to have different thermal expansion behaviors, causing the distortion of the crystal cell. An average thermal expansion coefficient (1.1 x 10-5 K-1) was obtained. The structural change of Ni-Cu alloy nanowires with temperature was discussed.

  2. Deproteinization technique stabilizes the adhesion of the fiberglass post relined with resin composite to root canal.

    Science.gov (United States)

    Cecchin, Doglas; Almeida, José F A; Gomes, Brenda P F A; Zaia, Alexandre A; Ferraz, Caio C R

    2012-02-01

    To evaluate the effects of pretreatment of root dentin by 5.25% sodium hypochlorite (NaOCl) alone, associated with 2% chlorhexidine in gel base (CHX) and/or ethanol (EtOH), and the air-drying technique (Air) on the bond strength and adhesive durability of fiberglass post relined with resin composite to root dentin. A total of 100 bovine incisor roots were divided into 10 groups: G1 (control), irrigation with physiologic solution; G2, Air; G3, NaOCl; G4, NaOCl + Air; G5, NaOCl + EtOH; G6, NaOCl + EtOH + Air; G7, NaOCl + CHX; G8, NaOCl + CHX + Air; G9, NaOCl + CHX + EtOH; G10, NaOCl + CHX + EtOH + Air. Fiberglass post relined with resin composite was cemented and each group was randomly divided into two subgroups: 24 h of water storage and 12 months of water storage. The push-out test was performed and bond strength values were analyzed by ANOVA and Tukey's test. The use of NaOCl alone or associated with CHX had the highest values of bond strength with or without Air in the immediate and stored groups, being statistically similar to the immediate control group (p > 0.05). The groups using EtOH or Air alone had lower bond strength in the immediate and stored groups (p 0.05). The use of NaOCl or NaOCl associated with CHX preserved the bond strength immediate and for 12 months. The air-drying technique and the other associations decreased the immediate bond strength values. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 577-583, 2012. PMID:22102546

  3. Remote sensing techniques and in situ fluorometry as alternative methods for the determination of algae pigments in lakes - application to Lake Constance and small lakes

    Science.gov (United States)

    Wolf, Thomas; Heege, Thomas; Schenk, Karin; Stark, Markus; Stich, Hans-Bernd

    2014-05-01

    Satellite based remote sensing techniques were used in order to assess the variability of Chlorophyll-a distributions in Lake Constance and additionally within some smaller lakes in the South of Germany. For Lake Constance we used for most investigations spatially medium resolved satellite scanners with a higher spectral resolution whereas in the case of smaller lakes having a size of 1 … 10 km spatially highly resolved satellite scanners were used having a lower spectral resolution. The satellite imagery allowed for a higher spatial as well temporal resolution of information about Chlorophyll-a distribution in these lakes compared to classical methodologies as water sampling and subsequent species analysis using microscopes and/or HPLC analysis for accessory algae pigments. We found - depending on weather and hydrodynamic conditions - highly variable Chlorophyll-a distributions under some circumstances whereas there are as well time periods when almost perfectly homogeneous distributions of Chlorophyll-a where detected in Lake Constance. Additionally we used HPLC analysis in order to validate the satellite remote sensing results showing good agreement between in situ measured and remote sensing values for Chlorophyll-a. During some measurement campaigns in Lake Constance we used an in situ fluorometer probe (BBE FluoroProbe) in order to determine the spatial fluctuations of Chlorophyll-a and additional accessory algae pigments. These algae pigments were measured along horizontal transects using a temporal sampling interval of about dt=2 … 10 seconds giving a high spatial sampling frequency in the order O[10 … 50]m. Based on these horizontal records we can get further insight into the spatial fluctuations of algae pigments and their spatial patterns in Lake Constance. Characteristics of these patterns can be quantified using some patchiness state vector (psv) summarizing different specific features of the algae distribution into some vector quantity. Special focus is given to the use of remote imagery from smaller lakes, where an additional methodology was applied using some basic assumptions in order to estimate the maxima of Chlorophyll-a in these smaller waters. In contrary to classical methods this approach is able to give estimates of maximum Chlorophyll-a content for many lakes at the same time. The potential of this methodology as a monitoring tool giving an indication where harmful developments in lakes (e.g. eutrophication, harmful algae blooms) might occur is analyzed.

  4. Implementation of field techniques to stabilize abandoned oil wells - Boyd's creek, Kentucky

    International Nuclear Information System (INIS)

    At Boyd's Creek, commercial crude-oil drilling production began in the early 1860s. Countless unrecorded exploration wells were drilled and many have been found to be improperly abandoned. The Corniferous limestone is the first oil producing interval and is situated at an average subsurface depth of 135 feet. The potential for impacting natural resources is high because of the shallow depth(s) of the Corniferous limestone and the presence of overlying artesian sulfur-water zones which routinely mix with brine and oil in uncased boreholes. The occurrence of limestone related (karstic) features, such as fractures and dissolution cavities, and the close proximity of the Boyd's Creek oil field to nearby surface streams are also of concern. Initially, two abandoned wells were identified as flowing into nearby streams. Pursuant to federal removal authority provided by Subsection (c) of Section 311 of the Federal Water Pollution Control Act in accordance with Subtitle B of the Oil Pollution Act of 1990 and the National Contingency Plan, the Environmental Protection Agency has initiated cleanup operations within properties nearest to Boyd's Creek. Most wells are difficult to identify because they lack any casing strings and/or they have been buried with soil to hide uncontrolled flows at the surface. Field operations have included the utilization of multiple geophysical techniques to identify anomaly areas thought to represent buried unplugged wells. These include the excavatunplugged wells. These include the excavation of surface soils down to the underlying limestone bedrock to search for cable tool and rotary boreholes, the drilling out of old wells using conventional industry technology and standards to plug them permanently with cement, the construction of temporary underflow dams downgradient from identified oil spills to minimize impacts on Boyd's Creek and its adjoining tributaries, and the burning of spilled product in temporary holding pits to minimize associated cleanup cost

  5. Phase stability of V-Ta alloy using cluster expansion and Monte Carlo techniques

    International Nuclear Information System (INIS)

    Phase diagram of V-Ta alloy is studied by DFT total energy calculations combined with the cluster expansion (CE) and Monte Carlo techniques. In the CE method, the problem of computing the energies of the 2N possible configurations of a binary alloy is exactly mapped into a generalized Ising Hamiltonian: E(?) = ??m?J?i??i>, where ? is a cluster of atoms. The sum is over all clusters ? that are not equivalent by a symmetry operation of the lattice, whereas the average is taken over all clusters ? that are equivalent to ? by symmetry. The coefficients J? embody the energetics of the alloy and are the effective cluster interactions (ECI). These J's are determined from the energies of a small set of ordered configurations through a least-squares fit minimization. ATAT was used for constructing the CE and calculation of thermodynamic properties. Electronic structure calculations of ordered configurations, required for the construction of CE, are performed using VASP with GGA and PAW datasets. The free energies and phase boundaries of the alloy are calculated using Monte Carlo simulations in which the energetic is specified by the CE Hamiltonian. Our Monte Carlo simulation samples a semi-grand canonical ensemble in which the chemical potential and the temperature are specified externally. The composition is allowed to vary with the constraint of fixed total number of particles. Our CE of V-Ta alloy based on the bcc lattice includes 48 input structures, involves seven ECl, consisting of five pairs and an empty cluster and a point interaction, and samples all the configurations containing up to 12 atoms per unit cell. Nevertheless, our CE does not find any bee compound ground state, which is in agreement with experiment. Cluster expansion of V-Ta, based on the C15 Laves lattice establishes readily that V2Ta is the ground state composition. The phase boundaries computed using these two CE in the Monte Carlo simulations are, as shown in the figure, found to be in good agreement with the experimental literature

  6. COMPARISON BETWEEN DYNAMIC MUSCULAR STABILIZATION TECHNIQUE (DMST, YOGA THERAPY AND HOT PACKS IN IMPROVING GENERAL HEALTH STATUS OF POSTURAL LOW BACK PAIN PATIENTS

    Directory of Open Access Journals (Sweden)

    Deepak Chhabra

    2015-06-01

    Full Text Available Background: Different interventions can reduce the burden of postural low back pain. For example the use of Dynamic Muscular Stabilization Technique(DMST, Yoga Therapy and Hot Packs, which aids patients by muscle strengthening and relaxation. This study is aimed to evaluate to what extent the above techniques can improve the quality of life in those who suffer from the condition. Materials and Methods: This was a randomized controlled trial. Thirty subjects (15 male and 15 females with postural low back pain (n=30 were randomly divided into three groups. Group A (DMST Group; n = 10, Group B (Yoga Group; n = 10 and Group C (Control Group; n = 10. Then General Health Status using SF – 36 QOL was assessed at 0, 1st and 2nd week. The values were compared between the three groups. Results: The Dynamic Muscular Stabilization Technique was effective in improving general health status; significant differences were found on both physical and mental health components of SF – 36 QOL. Yoga Therapy was found effective over Hot Packs. The mean improvement overall on general health status was significantly better to Dynamic Muscular Stabilization Technique. Conclusion: The Dynamic Muscular Stabilization Technique is an effective intervention improving general health status over a period of 1 month in patients who experience postural low back pain.

  7. Applicability study of using in-situ gamma-ray spectrometry technique for 137Cs and 210Pbex inventories measurement in grassland environments

    International Nuclear Information System (INIS)

    In-situ measurement of fallout radionuclides 137Cs and 210Pbex has the potential to assess soil erosion and sedimentation rapidly. In this study, inventories of 137Cs and 210Pbex in the soil of Inner Mongolia grassland were measured using an In-situ Object Counting System (ISOCS). The results from the field study indicate that in-situ gamma-ray spectrometry has the following advantages over traditional laboratory measurements: no extra time is required for sample collection, no reference inventories are required, more economic, prompt availability of the results, the ability to average radionuclide inventory over a large area, and high precision.

  8. Determination of Nutritional Value and Digestibility and Degradability of Twigs in Four Tree Species through Chemical and in situ (Nylon Bags Techniques

    Directory of Open Access Journals (Sweden)

    H. Yosefifar

    2012-07-01

    Full Text Available This study has been conducted in order to determine nutritional value and digestibility and degradability of twigs in four tree species including Zelkova carpinifolia, Gleditchia caspica, Populus deltoids and Quercus castanaefolia through chemical and in situ techniques using 3 fistulated sheep in National Research Institute for Animal Science, IRAN. The experiment conducted based on Randomized Complete Block Design and obtained data were analyzed by software SAS and Neway. Chemical compounds (crude protein (CP, Neutral Detergent Fiber (NDF, Acid Detergent Fiber (ADF, Ether Extract (EE, Ash, Crude Fiber (CF, NFC(Non Fiber Carbohydrate, Nitrogen Free Extract (NFE and organic material (OM and degradation (dry matter and protein were determined. Amount of crude protein for 4 species are as follow Z. carpinifolia (11%, G. caspica (15.4%, P. deltoids (10.3% and Q. castanaefolia (9.5%, also amount of crude fiber in these trees are respectively 32.7, 18.6, 13.9 and 22.9%. Survey conducted on species’ degradation and on amounts of dry matter and protein which disappear after 0, 4, 8, 16, 24, 48, 72 and 96 hours. Results of degradation in dry matter and protein showed that extent of degradation has been an uptrend over time of incubation and it follows a similar trend at all times. The most degradation of dry matter (80.6% and protein (91.6% are related to G. caspica and the least degradation of dry matter (36% and protein (38.4% are related to Q. castanaefolia. Results showed that as a replacement or a complementary for alfalfa, the four considered tree species can provide some parts of food requirements by livestock through a correct programming.

  9. The influence of Reinforcement Technique on the Calcium Chloride (CaCl2) & Granulated Blast Furnace Slag (GBFS) Stabilized Marine Clay for Foundation Soilbeds

    OpenAIRE

    D. Koteswara Rao,; G.V.R. Prasada Raju,; Srinivasa Rao Gadde

    2011-01-01

    In general, the soils which are existing in the coastal corridors are Soft Marine Clays formed by the deposits and generally weak and possesses high deformation values in nature. It is essential to study the various techniques for the improvement of marine clays, especially in case of infra-structure development. The present study dealswith the stabilization of marine clay using GBFS and calcium chloride and also the effect of reinforcement technique for improving the load carrying capacity o...

  10. Production of antibacterial colored viscose fibers using in situ prepared spherical Ag nanoparticles.

    Science.gov (United States)

    Emam, Hossam E; Mowafi, Salwa; Mashaly, Hamada M; Rehan, Mohamed

    2014-09-22

    In situ incorporation technique was used for coloration and acquiring excellent antibacterial properties for viscose fibers by silver nanoparticles (AgNPs). AgNPs were prepared in situ and incorporated in viscose matrix directly without using any other reducing and stabilizing agents. The main objective of this research was to successfully employ the reducing and stabilizing features of cellulose to produce nanosilver-viscose composites. Coloration of fibers after in situ AgNPs incorporation is related to surface plasmon resonance of silver. Colorimetric data were recorded as a function of washings to characterize the final colored fibers. Fastness properties and silver release were all measured to study the washable and wear off properties. Depending on the silver concentration, yellowish colored fibers with different shades were produced. Good fastness properties were obtained after 20 washings without using any crosslinker or binder. The colored fibers had excellent antibacterial activities against Escherichia coli, even after 20 washings. PMID:24906741

  11. Analysis of flow and density oscillations in a swirl-stabilized flame employing highly resolving optical measurement techniques

    Science.gov (United States)

    Fischer, Andreas; König, Jörg; Czarske, Jürgen; Peterleithner, Johannes; Woisetschläger, Jakob; Leitgeb, Thomas

    2013-12-01

    Modern aircraft engines operate with a reduced core air mass flow, which is challenging regarding an efficient and most of all stable combustion of fuel. A variable geometry burner investigated here allows a stable lean combustion with lower air mass flow rate than with a fixed geometry. In order to optimize such burners further, the occurring flame instabilities have to be investigated. This requires optical measurement techniques with a high measurement rate and an insensitivity regarding flame glow. Concerning flow velocity measurements, the frequency modulated Doppler global velocimetry (FM-DGV) fulfills these demands. In the swirl-stabilized flame of the variable geometry burner, spectra up to 2.5 kHz of the flow velocity field were obtained with FM-DGV. For example, a resonance peak at about 255 Hz was identified in the swirled flame, which also occurs in complementing density measurements by laser interferometric vibrometry. The combined analysis of velocity and density oscillations offer new insights into the physics of flame flows.

  12. Elaboration of Nanocomposites Based on Poly (Ethyl Methacrylate-co-Acrylonitrile) by In Situ Polymerization Using an Algerian Bentonite. Thermal Stability and Kinetic Study

    OpenAIRE

    Djadoun S.; Kadi S.

    2012-01-01

    This contribution focuses on the synthesis and characterization of nanocomposites based on poly (ethyl methacrylate-co-acrylonitrile) (PEMAN) and different loadings of an organically modified bentonite from Algeria prepared via in situ polymerization. TEM images and X-ray patterns revealed that depending on the loading of this clay, intercalated or partially exfoliated nanocomposites were obtained. These nanocomposites showed an increase in their glass transition temperature co...

  13. ENVIRONMENTAL MANAGEMENT SCIENCE PROGRAM PROJECT NUMBER 87016 CO-PRECIPITATION OF TRACE METALS IN GROUNDWATER AND VADOSE ZONE CALCITE: IN SITU CONTAINMENT AND STABILIZATION OF STRONTIUM-90 AND OTHER DIVALENT METALS AND RADIONUCLIDES AT ARID WESTERN DOE SITES

    International Nuclear Information System (INIS)

    Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) weapons complex. In situ containment and stabilization of these contaminants in vadose zones or groundwater is a cost-effective treatment strategy. Our facilitated approach relies upon the hydrolysis of introduced urea to cause the acceleration of calcium carbonate precipitation (and trace metal coprecipitation) by increasing groundwater pH and alkalinity (Fujita et al., 2000; Warren et al., 2001). Subsurface urea hydrolysis is catalyzed by the urease enzyme, which may be either introduced with the urea or produced in situ by ubiquitous subsurface urea hydrolyzing microorganisms. Because the precipitation processes are irreversible and many western aquifers are saturated with respect to calcite, the co-precipitated metals and radionuclides will be effectively removed from groundwater. The rate at which trace metals are incorporated into calcite is a function of calcite precipitation kinetics, adsorption interactions between the calcite surface and the trace metal in solution (Zachara et al., 1991), solid solution properties of the trace metal in calcite (Tesoriero and Pankow, 1996), and also the surfaces upon which the calcite is precipitating. A fundamental understanding of the coupling of calcite precipitation and trace metal partitioning, and how this occurs in aquifers and vadose environments is lacking. This report summarizes work unde lacking. This report summarizes work undertaken during the second year of this project

  14. In Situ Studies of Fe4+ Stability in ?-Li3Fe2(PO4)3 Cathodes for Li Ion Batteries

    DEFF Research Database (Denmark)

    Christiansen, Ane Sælland; Johnsen, Rune E.

    2015-01-01

    In commercial Fe-based batteries the Fe2+/Fe3+ oxidation states are used, however by also utilizing the Fe4+ oxidation state, intercalation of up to two Li ions per Fe ion could be possible. In this study, we investigate whether Fe4+ can be formed and stabilized in ?-Li3Fe2(PO4)3. The work includes in situ synchrotron X-ray powder diffraction studies (XRPD) during charging of ?-Li3Fe2(PO4)3 up to 5.0 V vs. Li/Li+. A novel capillary-based micro battery cell for in situ XRPD has been designed for this. During charge, a plateau at 4.5 V was found and a small contraction in volume was observed, indicating some Li ion extraction. The volume change of the rhombohedral unit cell is anisotropic, with a decrease in the a parameter and an increase in the c parameter during the Li ion extraction. Unfortunately, no increased discharge capacity was observed and Mössbauer spectroscopy showed no evidence of Fe4+ formation. Oxidation of the organic electrolyte is inevitable at 4.5 V but this alone cannot explain the volume change. Instead, a reversible oxygen redox process (O2? ? O?) could possibly explain and charge compensate for the reversible extraction of lithium ions from ?-Li3Fe2(PO4)3.

  15. Influence of in situ synthesized TiC on thermal stability and corrosion behavior of Zr{sub 60}Cu{sub 10}Al{sub 15}Ni{sub 15} amorphous composites

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Jiwei; Teng, Xinying, E-mail: mse_tengxy@ujn.edu.cn; Zhou, Guorong; Leng, Jinfeng; Zhao, Degang

    2014-03-01

    In situ synthesized TiC particles were prepared by a thermal explosion method. Adding “in situ synthesized” TiC into Zr{sub 60}Cu{sub 10}Al{sub 15}Ni{sub 15} glass matrix to obtain amorphous matrix composites was achieved. The corrosion behavior of Zr{sub 60}Cu{sub 10}Al{sub 15}Ni{sub 15} amorphous composites was evaluated using potentiodynamic polarization measurements in 3.5 wt% NaCl solution at room temperature. The results show that the microhardness and thermal stability are improved apparently, while the TiC (?0.6 wt%) does not significantly affect the supercooled liquid behavior. Moreover, the corrosion resistance is improved apparently because the nanocrystals accelerate the diffusion of passive elements for faster formation of the protective passive film at nanocrystals/amorphous interfaces. However, when the TiC content is more than 0.6 wt%, both glass forming ability and corrosion resistance are reduced significantly.

  16. Using the charge-stabilization technique in the double ionization potential equation-of-motion calculations with dianion references.

    Science.gov (United States)

    Ku?, Tomasz; Krylov, Anna I

    2011-08-28

    The charge-stabilization method is applied to double ionization potential equation-of-motion (EOM-DIP) calculations to stabilize unstable dianion reference functions. The auto-ionizing character of the dianionic reference states spoils the numeric performance of EOM-DIP limiting applications of this method. We demonstrate that reliable excitation energies can be computed by EOM-DIP using a stabilized resonance wave function instead of the lowest energy solution corresponding to the neutral + free electron(s) state of the system. The details of charge-stabilization procedure are discussed and illustrated by examples. The choice of optimal stabilizing Coulomb potential, which is strong enough to stabilize the dianion reference, yet, minimally perturbs the target states of the neutral, is the crux of the approach. Two algorithms of choosing optimal parameters of the stabilization potential are presented. One is based on the orbital energies, and another--on the basis set dependence of the total Hartree-Fock energy of the reference. Our benchmark calculations of the singlet-triplet energy gaps in several diradicals show a remarkable improvement of the EOM-DIP accuracy in problematic cases. Overall, the excitation energies in diradicals computed using the stabilized EOM-DIP are within 0.2 eV from the reference EOM spin-flip values. PMID:21895161

  17. An Assessment of the Stability and the Potential for In-Situ Synthesis of Regulated Organic Compounds in High Level Radioactive Waste Stored at Hanford, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Wiemers, K.D.; Babad, H.; Hallen, R.T.; Jackson, L.P.; Lerchen, M.E.

    1999-01-04

    The stability assessment examined 269 non-detected regulated compounds, first seeking literature references of the stability of the compounds, then evaluating each compound based upon the presence of functional groups using professional judgment. Compounds that could potentially survive for significant periods in the tanks (>1 year) were designated as stable. Most of the functional groups associated with the regulated organic compounds were considered unstable under tank waste conditions. The general exceptions with respect to functional group stability are some simple substituted aromatic and polycyclic aromatic compounds that resist oxidation and the multiple substituted aliphatic and aromatic halides that hydrolyze or dehydrohalogenate slowly under tank waste conditions. One-hundred and eighty-one (181) regulated, organic compounds were determined as likely unstable in the tank waste environment.

  18. An Assessment of the Stability and the Potential for In-Situ Synthesis of Regulated Organic Compounds in High Level Radioactive Waste Stored at Hanford, Richland, Washington

    International Nuclear Information System (INIS)

    The stability assessment examined 269 non-detected regulated compounds, first seeking literature references of the stability of the compounds, then evaluating each compound based upon the presence of functional groups using professional judgment. Compounds that could potentially survive for significant periods in the tanks (>1 year) were designated as stable. Most of the functional groups associated with the regulated organic compounds were considered unstable under tank waste conditions. The general exceptions with respect to functional group stability are some simple substituted aromatic and polycyclic aromatic compounds that resist oxidation and the multiple substituted aliphatic and aromatic halides that hydrolyze or dehydrohalogenate slowly under tank waste conditions. One-hundred and eighty-one (181) regulated, organic compounds were determined as likely unstable in the tank waste environment

  19. High temperature exposure of in-situ thermocouple fixed-point cells: stability with up to three months of continuous use

    Science.gov (United States)

    Elliott, C. J.; Greenen, A.; Lowe, D.; Pearce, J. V.; Machin, G.

    2015-04-01

    To categorise thermocouples in batches, manufacturers state an expected operating tolerance for when the thermocouples are as-new. In use, thermocouple behaviour can rapidly change and the tolerance becomes invalid, especially when used at high temperatures (i.e. above 1000?°C) as the processes leading to de-calibration, such as oxidation and contamination, can be very fast and lead to erroneous readings. In-situ thermocouple self-validation provides a method to track the drift and correct the thermocouple reading in real-time, but it must be shown to be reliable. Two miniature temperature fixed-point cells designed at NPL for in-situ thermocouple self-validation, the first containing a Pt-C eutectic alloy and the second containing a Ru-C eutectic alloy, have been exposed to temperatures close to their melting point for 2200?h and 1570?h, respectively, and continuously, for up to three months. Recalibration after this long-term high-temperature exposure, where a tantalum-sheathed thermocouple was always in place, is used to show that no significant change of the temperature reference point (the melting temperature) has occurred in either the Pt-C ingot or the Ru-C ingot, over timescales far longer than previously demonstrated and approaching that required by industry for practical use of the device.

  20. A field-validated model for in situ transport of polymer-stabilized nZVI and implications for subsurface injection.

    Science.gov (United States)

    Krol, Magdalena M; Oleniuk, Andrew J; Kocur, Chris M; Sleep, Brent E; Bennett, Peter; Xiong, Zhong; O'Carroll, Denis M

    2013-07-01

    Nanoscale zerovalent iron (nZVI) particles have significant potential to remediate contaminated source zones. However, the transport of these particles through porous media is not well understood, especially at the field scale. This paper describes the simulation of a field injection of carboxylmethyl cellulose (CMC) stabilized nZVI using a 3D compositional simulator, modified to include colloidal filtration theory (CFT). The model includes composition dependent viscosity and spatially and temporally variable velocity, appropriate for the simulation of push-pull tests (PPTs) with CMC stabilized nZVI. Using only attachment efficiency as a fitting parameter, model results were in good agreement with field observations when spatially variable viscosity effects on collision efficiency were included in the transport modeling. This implies that CFT-modified transport equations can be used to simulate stabilized nZVI field transport. Model results show that an increase in solution viscosity, resulting from injection of CMC stabilized nZVI suspension, affects nZVI mobility by decreasing attachment as well as changing the hydraulics of the system. This effect is especially noticeable with intermittent pumping during PPTs. Results from this study suggest that careful consideration of nZVI suspension formulation is important for optimal delivery of nZVI which can be facilitated with the use of a compositional simulator. PMID:23725414

  1. Modified stabilization method for the tibial tuberosity advancement technique: a biomechanical study Modificação da técnica de avanço da tuberosidade tibial: estudo biomecânico

    OpenAIRE

    Bruno Testoni Lins; Sheila Canevese Rahal; Mário Jefferson Louzada; José Carlos Dalmas; André Luis Selmi

    2009-01-01

    The present study aimed to determine biomechanical alterations resultant from a modification in the fixation method of the tibial tuberosity advancement technique (TTA), originally described for stabilization of the cranial cruciate-deficient stifle. Ten adult mongrel dogs weighing 25-30kg were used. After euthanasia, performed for reasons unrelated to this study, the hind limbs were distributed into two groups: G1 operated (n=10) and G2 control (n=10), represented by the contralateral limb. ...

  2. The influence of Reinforcement Technique on the Calcium Chloride (CaCl2 & Granulated Blast Furnace Slag (GBFS Stabilized Marine Clay for Foundation Soilbeds

    Directory of Open Access Journals (Sweden)

    D. Koteswara Rao,

    2011-03-01

    Full Text Available In general, the soils which are existing in the coastal corridors are Soft Marine Clays formed by the deposits and generally weak and possesses high deformation values in nature. It is essential to study the various techniques for the improvement of marine clays, especially in case of infra-structure development. The present study dealswith the stabilization of marine clay using GBFS and calcium chloride and also the effect of reinforcement technique for improving the load carrying capacity of the foundation soil beds.

  3. Development and application of compact denuder sampling techniques with in situ derivatization followed by gas chromatography-mass spectrometry for halogen speciation in volcanic plumes

    Science.gov (United States)

    Rüdiger, Julian; Bobrowski, Nicole; Hoffmann, Thorsten

    2015-04-01

    Volcanoes are a large source for several reactive atmospheric trace gases including sulphur and halogen containing species. The detailed knowledge of volcanic plume chemistry can give insights into subsurface processes and can be considered as a useful geochemical tool for monitoring of volcanic activity, especially halogen to sulphur ratios (e.g. Bobrowski and Giuffrida, 2012; Donovan et al., 2014). The reactive bromine species bromine monoxide (BrO) is of particular interest, because BrO as well as SO2 are readily measurable by UV spectrometers at a safe distance. Furthermore it is formed in the plume by a multiphase reaction mechanism under depletion of ozone in the plume. The abundance of BrO changes as a function of the reaction time and therefore distance from the vent as well as the spatial position in the plume. Due to the lack of analytical approaches for the accurate speciation of certain halogens (HBr, Br2, Br, BrCl, HOBr etc.) there are still uncertainties about the magnitude of volcanic halogen emissions and in particular their specificationtheir species and therefore also in the understanding of the bromine chemistry in volcanic plumes (Bobrowski et al., 2007). In this study, the first application of a 1,3,5-trimethoxybenzene (1,3,5-TMB)-coated gas diffusion denuder (Huang and Hoffmann, 2008) on volcanic gases proved to be suitable to collect selectively gaseous bromine species with oxidation states of +1 or 0 (Br2 and BrO(H)), while being ignorant to HBr (OS -1). The reaction of 1,3,5-TMB with bromine gives 1-bromo-2,4,6-trimethoxybenzene (1-bromo-2,4,6-TMB) - other halogens give corresponding products. The diffusion denuder technique allows sampling of gaseous compounds exclusively without collecting particulate matter. Choosing a flow rate of 500 mL-min-1 and a denuder length of 0.5 m a nearly quantitative collection efficiency was achieved. Solvent elution of the derivatized analytes and subsequent analysis with gas chromatography-mass spectrometry gives a limit of detection below 1 ng of bromine. The method was applied on volcanic gas plumes at Mt. Etna and Mt. Stromboli in Italy in July 2014 and on fumarolic gas emissions at Mt. Lastarria in Chile in November 2014. The results show significant amounts of the concerning bromine species (lower ppb range). Comprehensive data evaluation and comparison with results of impinger extraction with NaOH solution as well as chamber experiments are still in progress. References Bobrowski, N. and G. Giuffrida: Bromine monoxide / sulphur dioxide ratios in relation to volcanological observations at Mt. Etna 2006-2009. Solid Earth, 3, 433-445, 2012 Bobrowski, N., R. von Glasow, A. Aiuppa, S. Inguaggiato, I. Louban, O. W. Ibrahim and U. Platt: Reactive halogen chemistry in volcanic plumes. J. Geophys. Res., 112, 2007 Donovan A., V. Tsanev, C. Oppenheimer and M. Edmonds: Reactive halogens (BrO and OClO) detected in the plume of Soufrière Hills Volcano during an eruption hiatus. Geochem. Geophys. Geosyst., 15, 3346-3363, 2014 Huang, R.-J. and T. Hoffmann: A denuder-impinger system with in situ derivatization followed by gas chromatography-mass spectrometry for the determination of gaseous iodine-containing halogen species. Journal of Chromatography A, 1210, 135-141, 2008

  4. Application of spectrophotometric, densitometric, and HPLC techniques as stability indicating methods for determination of Zaleplon in pharmaceutical preparations

    Science.gov (United States)

    Metwally, Fadia H.; Abdelkawy, M.; Abdelwahab, Nada S.

    2007-12-01

    Spectrophotometric, spectrodensitometric and HPLC are stability indicating methods described for determination of Zaleplon in pure and dosage forms. As Zaleplon is easily degradable, the proposed techniques in this manuscript are adopted for its determination in presence of its alkaline degradation product, namely N-[4-(3-cyano-pyrazolo[1,5a]pyridin-7-yl)-phenyl]- N-ethyl-acetamide. These approaches are successfully applied to quantify Zaleplon using the information included in the absorption spectra of appropriate solutions. The second derivative (D 2) spectrophotometric method, allows determination of Zaleplon without interference of its degradate at 235.2 nm using 0.01N HCl as a solvent with obedience to Beer's law over a concentration range of 1-10 ?g ml -1 with mean percentage recovery 100.24 ± 0.86%. The first derivative of the ratio spectra ( 1DD) based on the simultaneous use of ( 1DD) and measurement at 241.8 nm using the same solvent and over the same concentration range as (D 2) spectrophotometric method, with mean percentage recovery 99.9 ± 1.07%. The spectrodensitometric analysis allows the separation and quantitation of Zaleplon from its degradate on silica gel plates using chloroform:acetone:ammonia solution (9:1:0.2 by volume) as a mobile phase. This method depends on quantitave densitometric evaluation of thin layer chromatogram of Zaleplon at 338 nm over a concentration range of 0.2-1 ?g band -1, with mean percentage recovery 99.73 ± 1.35. Also a reversed-phase liquid chromatographic method using 5-C8 (22 cm × 4.6 mm i.d. 5 ?m particle size) column was described and validated for quantitation of Zaleplon using acetonitrile:deionised water (35:65, v/v) as a mobile phase using Paracetamol as internal standard and a flow rate of 1.5 ml min -1 with UV detection of the effluent at 232 nm at ambient temperature over a concentration range of 2-20 ?g ml -1 with mean percentage recovery 100.19 ± 1.15%. The insignificance difference of the proposed methods results with those of the reference one proved their accuracy and precision.

  5. Thermal stability in the blended lithium manganese oxide - Lithium nickel cobalt manganese oxide cathode materials: An in situ time-resolved X-Ray diffraction and mass spectroscopy study

    Science.gov (United States)

    Hu, Enyuan; Bak, Seong Min; Senanayake, Sanjaya D.; Yang, Xiao-Qing; Nam, Kyung-Wan; Zhang, Lulu; Shao, Minhua

    2015-03-01

    Thermal stabilities of a series of blended LiMn2O4 (LMO)-LiNi1/3Co1/3Mn1/3O2 (NCM) cathode materials with different weight ratios were studied by in situ time-resolved X-ray diffraction (XRD) combined with mass spectroscopy in the temperature range of 25 °C-580 °C under helium atmosphere. Upon heating, the electrochemically delithiated LMO changed into Mn3O4 phase at around 250 °C. Formation of MnO with rock-salt structure started at 520 °C. This observation is in contrast to the previous report for chemically delithiated LMO in air, in which a process of ?-MnO2 transforming to ?-MnO2 was observed. Oxygen peak was not observed in all cases, presumably as a result of either consumption by the carbon or detection limit. CO2 profile correlates well with the phase transition and indirectly suggests the oxygen release of the cathode. Introducing NCM into LMO has two effects: first, it makes the high temperature rock-salt phase formation more complicated with more peaks in CO2 profile due to different MO (M = Ni, Mn, Co) phases; secondly, the onset temperature of CO2 release is lowered, implying lowered oxygen release temperature. Upon heating, XRD patterns indicate the NCM part reacts first, followed by the LMO part. This confirms the better thermal stability of LMO over NCM.

  6. Tracer-level radioactive pilot-scale test of in situ vitrification technology for the stabilization of contaminated soil sites at ORNL

    International Nuclear Information System (INIS)

    This plan summarizes the activities to be performed during FY 1990 and FY 1991 for the tracer-level radioactive pilot-scale in situ vitrification (ISV) test. This test is the second step in evaluating ISV as a remedial action for the pits and trenches at Oak Ridge National Laboratory (ORNL). A previous test used nonradioactive tracers for cesium and strontium. This new test will again use a one-half-scale model of trench 7 and the pilot-scale ISV equipment of Pacific Northwest Laboratory (PNL). A small and precisely known amount of waste from a liquid waste disposal pit will be used for the test. An actually contaminated waste site cannot be used for this test because of the necessity to use an exactly known inventory of radionuclides so that a precise measurement of the volatilization of various constituents to the off-gas can be determined

  7. Molecular Interaction of a New Antibacterial Polymer with a Supported Lipid Bilayer Measured by an in situ Label-Free Optical Technique

    OpenAIRE

    Robert Horvath; Balázs Kobzi; Helmut Keul; Martin Moeller; Éva Kiss

    2013-01-01

    The interaction of the antibacterial polymer–branched poly(ethylene imine) substituted with quaternary ammonium groups, PEO and alkyl chains, PEI25QI5J5A815–with a solid supported lipid bilayer was investigated using surface sensitive optical waveguide spectroscopy. The analysis of the optogeometrical parameters was extended developing a new composite layer model in which the structural and optical anisotropy of the molecular layers was taken into consideration. Following in situ the change o...

  8. Trace Metals in Groundwater and Vadose Zone Calcite: In Situ Containment and Stabilization of Stronthium-90 and Other Divalent Metals and Radionuclides at Arid Western DOE Sites: Final Report for Award Number DE-FG07-02ER63486 to the University of Idaho (RW Smith) Environmental Management Science Program Project Number 87016

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Robert W.; Fujita, Yoshiko

    2007-11-07

    Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) energy research and weapons complex. In situ containment and stabilization of these contaminants represents a cost-effective treatment strategy that minimizes workers’ exposure to hazardous substances, does not require removal or transport of contaminants, and generally does not generate a secondary waste stream. We have investigated an in situ bioremediation approach that immobilizes radionuclides or contaminant metals (e.g., strontium-90) by their microbially facilitated co-precipitation with calcium carbonate in groundwater and vadose zone systems. Calcite, a common mineral in many aquifers and vadose zones in the arid west, can incorporate divalent metals such as strontium, cadmium, lead, and cobalt into its crystal structure by the formation of a solid solution. Collaborative research undertaken by the Idaho National Laboratory (INL), University of Idaho, and University of Toronto as part of this Environmental Management Science Program project has focused on in situ microbially-catalyzed urea hydrolysis, which results in an increase in pH, carbonate alkalinity, ammonium, calcite precipitation, and co-precipitation of divalent cations. In calcite-saturated aquifers, microbially facilitated co-precipitation with calcium carbonate represents a potential long-term contaminant sequestration mechanism. Key results of the project include: **Demonstrating the linkage between urea hydrolysis and calcite precipitation in field and laboratory experiments **Observing strontium incorporation into calcite precipitate by urea hydrolyzers with higher distribution coefficient than in abiotic **Developing and applying molecular methods for characterizing microbial urease activity in groundwater including a quantitative PCR method for enumerating ureolytic bacteria **Applying the suite of developed molecular methods to assess the feasibility of the proposed bioremediation technique at a contaminated site located within the 100-N area of the Hanford, Washington site **Assessing the role of nitrification on the persistence of precipitated calcite by modifying primers for identification of the amoA gene region of various ammonia oxidizing bacteria (AOB) for characterizing AOB in the field

  9. Trace Metals in Groundwater and Vadose Zone Calcite: In Situ Containment and Stabilization of Strontium-90 and Other Divalent Metals and Radionuclides at Arid Western DOE Sites: Final Report for Award Number DE-FG07-02ER63486 to the University of Idaho (RW Smith) Environmental Management Science Program Project Number 87016

    International Nuclear Information System (INIS)

    Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) energy research and weapons complex. In situ containment and stabilization of these contaminants represents a cost-effective treatment strategy that minimizes workers exposure to hazardous substances, does not require removal or transport of contaminants, and generally does not generate a secondary waste stream. We have investigated an in situ bioremediation approach that immobilizes radionuclides or contaminant metals (e.g., strontium-90) by their microbially facilitated co-precipitation with calcium carbonate in groundwater and vadose zone systems. Calcite, a common mineral in many aquifers and vadose zones in the arid west, can incorporate divalent metals such as strontium, cadmium, lead, and cobalt into its crystal structure by the formation of a solid solution. Collaborative research undertaken by the Idaho National Laboratory (INL), University of Idaho, and University of Toronto as part of this Environmental Management Science Program project has focused on in situ microbially-catalyzed urea hydrolysis, which results in an increase in pH, carbonate alkalinity, ammonium, calcite precipitation, and co-precipitation of divalent cations. In calcite-saturated aquifers, microbially facilitated co-precipitation with calcium carbonate represents a potential long-term contaminant sequestration mechanism. Key results of the project include: **Demonstrating the linkage between urea hydrolysis and calcite precipitation in field and laboratory experiments **Observing strontium incorporation into calcite precipitate by urea hydrolyzers with higher distribution coefficient than in abiotic **Developing and applying molecular methods for characterizing microbial urease activity in groundwater including a quantitative PCR method for enumerating ureolytic bacteria **Applying the suite of developed molecular methods to assess the feasibility of the proposed bioremediation technique at a contaminated site located within the 100-N area of the Hanford, Washington site **Assessing the role of nitrification on the persistence of precipitated calcite by modifying primers for identification of the amoA gene region of various ammonia oxidizing bacteria (AOB) for characterizing AOB in the field

  10. Methods of investigating and testing geological features and ground and techniques of evaluating aseismatic stability of ground for nuclear power stations

    International Nuclear Information System (INIS)

    As to the ground for nuclear power stations, it is required to carry out the construction of high reliability based on the analysis and design by detailed investigation, test and reliable techniques. For this purpose, when the location of nuclear power stations is examined, the safety of the foundation ground for nuclear reactors is to be evaluated in conformity with the basic policy shown in the ''Guideline for the examination of aseismatic design regarding power reactor facilities'' and the ''Guide for safety examination regarding the geological features and ground for nuclear power stations''. However, geological features and ground are diverse from place to place, accordingly, it is desired to clarify the technological handling in actual application, and it is necessary to illustrate using examples. The Ground Subcommittee of Japan Society of Civil Engineers examined this problem for four and a half years, and published this report, which consists of Part : General remarks, Part 2 : Method of investigating geological features, Part 3 : Method of investigating and testing ground, Part 4 : Techniques of evaluating the aseismatic stability of the foundation ground for reactor buildings and examples, Part 5 : Techniques of evaluating the aseismatic stability of surrounding slopes and examples, and Part 6 : Techniques of evaluating the aseismatic safety of important outdoor structures and example design. (Kako, I.)

  11. A review of joining techniques for SiCf/SiC composites for first wall applications

    International Nuclear Information System (INIS)

    Many methods for joining monolithic and composite silicon carbide are available. Three techniques are candidates for use in fusion energy systems: in-situ displacement reactions, pre-ceramic polymer adhesives, and reaction bonding. None of the methods are currently developed enough to satisfy all of the criteria required, i.e., low temperature fabrication, high strength, and radiation stability. 58 refs

  12. Rehabilitation techniques for polluted sites and soils. Synthesis files; Techniques de rehabilitation des sites et sols pollues. Fiches de synthese

    Energy Technology Data Exchange (ETDEWEB)

    Roudier, P. [SITA 75 - Paris (France)

    2004-01-01

    The files presented in this article represent the status of the different available techniques for the rehabilitation of polluted soils and aquifers. Each file treats of both the theoretical aspect (basic principle) of the technique and of the practical aspect through the technical means implemented. It indicates also the type of pollutant concerned by the technique, the expected results and the maturity of the process. Moreover, concrete examples of rehabilitations are presented and justified for different polluting compounds. The techniques presented are not exhaustive and the choice of a technique requires the consideration of numerous and various parameters linked with the soil chemistry, the nature of the pollutants, the site constraints and the technical-economical factor: air sparging, natural attenuation, reactive barriers, bio-augmentation, bio-slurry, bio-stimulation, bio-hillock, bio-venting, soils composting, ex-situ thermal desorption, in-situ thermal desorption, electro-kinetics, electro-oxidation, excavation, incineration, ex-situ washing (soil washing), in-situ washing (flushing), microwaves, in-situ oxidation, UV photo-oxidation, phyto-remediation, pump and treat, pyrolysis, beating back - skimming, reduction, slurping (triple-phase extraction), solidification/stabilization, surfactants/co-surfactants, solvents/co-solvents, aerobic biological processes, anaerobic biological processes, fungi processes, grain-size sorting, ultrasonic waves, venting (soil vapor extraction), vitrification. (J.S.)

  13. Voltage stability evaluation facing small disturbances by means of the modal analysis technique; Evaluacion de la estabilidad de voltaje ante disturbios pequenos mediante la tecnica de analisis modal

    Energy Technology Data Exchange (ETDEWEB)

    Leon Rodriguez, Daniel

    2000-12-15

    The economic development of the countries has taken implicit a growing industrialization the one which, joined to those every time bigger resident's necessities, it has caused a constant and progressive increment in the electric power demand. However, in the last years the growth of the electric network of these systems has been more and more limited for diverse such factors as the ecology and the economy, as well as for the social and political costs that implies each new construction in the system. With the presence of these restrictions the electric systems in many cases, have been forced to satisfy the increments in the demand making a more exhaustive use of the infrastructure that they have available and the incorporation of only a few new system elements or constructions. These aspects have caused such systems to operate with more limited security margins and that their stability has to be analyzed in a reliable and precise way. Taking into account the previously mentioned aspects, as the electric systems have had the necessity of operating under forced conditions to satisfy the load demand, voltage stability problems have been presented with more frequency causing serious disturbances and in some cases, total blackouts. With these problems, the voltage stability analysis has taken bigger importance in the studies that the electric utilities carry out. This issue has caused that bigger resources are dedicated for the investigation of this phenomenon with the purpose of understanding and developing tools that allow studying it in a more complete and more truthful way. Modal analysis is one of the most recent and popular steady techniques the one that, from its appearance has had a great peak due to the valuable and quick information that provides, besides its implementation easiness and the little effort computational that it requires. In this work is carried out the voltage stability evaluation of a real electric system applying in a combined way the modal analysis technique with other conventional techniques as the curves P-V and V-Q. It also illustrated the way in that the different information obtained of these techniques is supplemented to achieve a more complete and more representative voltage stability study. Besides analyzing the voltage stability for the normal operation conditions (base case), also are evaluated three different reactive compensation alternatives with the object of improving the margin or distance to the system voltage instability. The results obtained with each one of the compensation options are compared to each other and commented for finally, to propose the alternative that presents the biggest advantages from the voltage stability point of view. The selection of the most appropriate places to locate the reactive compensation is carried out being based on the bus participation factors by the modal analysis for the base case. Finally, taking into account the tools and the procedures used in this work to carry out the voltage stability analysis, one of the main purposes consists on proposing a methodology that allows indicating certain guidelines that help carry out voltage stability studies in a quicker and simpler way. [Spanish] El desarrollo economico de los paises ha llevado implicita una creciente industrializacion la cual, aunada a las cada vez mayores necesidades de sus pobladores, ha provocado un constante y progresivo incremento en la demanda de energia electrica. Sin embargo, en los ultimos anos el crecimiento de la red electrica de estos sistemas se ha visto cada vez mas limitado por diversos factores tales como la ecologia, la economia y por los costos sociales y politicos que cada nueva obra implica. Ante la presencia de estas restricciones los sistemas electricos en muchos casos, se han visto obligados a satisfacer los incrementos en la demanda haciendo un uso mas exhaustivo de la infraestructura que tienen disponible y la incorporacion de solo unas cuantas obras nuevas. Estos aspectos han provocado que dichos sistemas operen con margenes de seguridad mas limitados y qu

  14. Combined characterization techniques to understand the stability of a variety of organic photovoltaic devices: the ISOS-3 inter-laboratory collaboration

    Science.gov (United States)

    Lira-Cantu, Monica; Tanenbaum, David M.; Norrman, Kion; Voroshazi, Eszter; Hermenau, Martin; Lloyd, Matthew T.; Teran-Escobar, Gerardo; Galagan, Yulia; Zimmermann, Birger; Hösel, Markus; Dam, Henrik F.; Jørgensen, Mikkel; Gevorgyan, Suren; Lutsen, Laurence; Vanderzande, Dirk; Hoppe, Harald; Rösch, Roland; Würfel, Uli; Andriessen, Ronn; Rivaton, Agnès.; Uzuno?lu, Gül?ah Y.; Germack, David; Andreasen, Birgitta; Madsen, Morten V.; Bundgaard, Eva; Krebs, Frederik C.

    2012-10-01

    This work is part of the inter-laboratory collaboration to study the stability of seven distinct sets of state-of-the-art organic photovoltaic (OPVs) devices prepared by leading research laboratories. All devices have been shipped to and degraded at the Danish Technical University (DTU, formerly RISO-DTU) up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. In this work we present a summary of the degradation response observed for the NREL sample, an inverted OPV of the type ITO/ZnO/P3HT:PCBM/PEDOT:PSS/Ag/Al, under full sun stability test. The results reported from the combination of the different characterization techniques results in a proposed degradation mechanism. The final conclusion is that the failure of the photovoltaic response of the device is mainly due to the degradation of the electrodes and not to the active materials of the solar cell.

  15. Freeze stabilization and cryopreparation technique for visualizing the water distribution in woody tissues by X-ray imaging and cryo-scanning electron microscopy.

    Science.gov (United States)

    Utsumi, Yasuhiro; Sano, Yuzou

    2014-01-01

    The protocol of freeze stabilization and cryopreparation techniques to examine the distribution of water in living tree stems by X-ray imaging and cryo-scanning electron microscopy have been developed and described. The brief procedures are as follows. Firstly, a portion of transpiring stem is frozen in the standing state with liquid nitrogen to stabilize the water that is present in the conducting tissue. After filling with liquid nitrogen, discs are then collected from the frozen portion of the stem and stored in liquid nitrogen. In a low-temperature room, the samples for X-ray imaging are sectioned with a fine handsaw, and trimmed sample blokes for cryo-scanning electron microscopy are cleanly planed using a sliding microtome. Finally, the frozen sections are irradiated in a soft X-ray apparatus, and the small blocks are examined in cryo-scanning electron microscope after freeze-etching and metal coating. PMID:24357385

  16. Tracer-level radioactive pilot-scale test of in situ vitrification for the stabilization of contaminated soil sites at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, B.P.; Jacobs, G.K.; Naney, M.T. (Oak Ridge National Lab., TN (United States)); Dunbar, N.W. (New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States)); Tixier, J.S.; Powell, T.D. (Pacific Northwest Lab., Richland, WA (United States))

    1992-11-01

    A field demonstration of in situ vitrification (ISV) was completed in May 1991, and produced approximately 12 Mg of melted earthen materials containing 12.7 mCi of radioactivity within 500 g of sludge in amodel of an old seepage trench waste disposal unit. Past waste disposal operations at Oak Ridge National Laboratory have left several contaminated seepage sites. In planning for remediation of such sites, ISV technology has been identified as a leading candidate because of the high risks associated with any retrieval option and because of the usual high quality of vitreous waste form. Major isotopes placed in the test trench were [sup 137]Cs and [sup 90]Sr, with lesser amounts of [sup 6O]Co, [sup 241]Am, and [sup 239,240]Pu. A total of 29 MWh of electrical power was delivered to the ground over a 5-day period producing a melt depth of 8.5 ft. During melting, 2.4% of the [sup 137]Cs volatilized from the melt into an off-gas containment hood and was captured quantitatively on a high efficiency particulate air filter. No volatilization of [sup 90]Sr, [sup 241]Am, or [sup 239,240]Pu was detected and > 99.993% retention of these isotopes in the melt was estimated. The use of added rare earth tracers (Ce, La, and Nd), as surrogates for transuranic isotopes, led to estimated melt retentions of >99.9995% during the test. The molten material, composed of the native soil and dolomitic limestone used for filling the test trench, reached a processing temperature of 1500[degrees]C. Standardized leaching procedures using Product Consistency Testing indicated that the ISV product has excellent characteristics relative to other vitreous nuclear waste forms.

  17. Tracer-level radioactive pilot-scale test of in situ vitrification for the stabilization of contaminated soil sites at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, B.P.; Jacobs, G.K.; Naney, M.T. [Oak Ridge National Lab., TN (United States); Dunbar, N.W. [New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States); Tixier, J.S.; Powell, T.D. [Pacific Northwest Lab., Richland, WA (United States)

    1992-11-01

    A field demonstration of in situ vitrification (ISV) was completed in May 1991, and produced approximately 12 Mg of melted earthen materials containing 12.7 mCi of radioactivity within 500 g of sludge in amodel of an old seepage trench waste disposal unit. Past waste disposal operations at Oak Ridge National Laboratory have left several contaminated seepage sites. In planning for remediation of such sites, ISV technology has been identified as a leading candidate because of the high risks associated with any retrieval option and because of the usual high quality of vitreous waste form. Major isotopes placed in the test trench were {sup 137}Cs and {sup 90}Sr, with lesser amounts of {sup 6O}Co, {sup 241}Am, and {sup 239,240}Pu. A total of 29 MWh of electrical power was delivered to the ground over a 5-day period producing a melt depth of 8.5 ft. During melting, 2.4% of the {sup 137}Cs volatilized from the melt into an off-gas containment hood and was captured quantitatively on a high efficiency particulate air filter. No volatilization of {sup 90}Sr, {sup 241}Am, or {sup 239,240}Pu was detected and > 99.993% retention of these isotopes in the melt was estimated. The use of added rare earth tracers (Ce, La, and Nd), as surrogates for transuranic isotopes, led to estimated melt retentions of >99.9995% during the test. The molten material, composed of the native soil and dolomitic limestone used for filling the test trench, reached a processing temperature of 1500{degrees}C. Standardized leaching procedures using Product Consistency Testing indicated that the ISV product has excellent characteristics relative to other vitreous nuclear waste forms.

  18. Tracer-level radioactive pilot-scale test of in situ vitrification for the stabilization of contaminated soil sites at ORNL

    International Nuclear Information System (INIS)

    A field demonstration of in situ vitrification (ISV) was completed in May 1991, and produced approximately 12 Mg of melted earthen materials containing 12.7 mCi of radioactivity within 500 g of sludge in amodel of an old seepage trench waste disposal unit. Past waste disposal operations at Oak Ridge National Laboratory have left several contaminated seepage sites. In planning for remediation of such sites, ISV technology has been identified as a leading candidate because of the high risks associated with any retrieval option and because of the usual high quality of vitreous waste form. Major isotopes placed in the test trench were 137Cs and 90Sr, with lesser amounts of 6OCo, 241Am, and 239,240Pu. A total of 29 MWh of electrical power was delivered to the ground over a 5-day period producing a melt depth of 8.5 ft. During melting, 2.4% of the 137Cs volatilized from the melt into an off-gas containment hood and was captured quantitatively on a high efficiency particulate air filter. No volatilization of 90Sr, 241Am, or 239,240Pu was detected and > 99.993% retention of these isotopes in the melt was estimated. The use of added rare earth tracers (Ce, La, and Nd), as surrogates for transuranic isotopes, led to estimated melt retentions of >99.9995% during the test. The molten material, composed of the native soil and dolomitic limestone used for filling the test trench, reached a processing temperature of 1500 degrees C. Standardized leaching procedures using Product Consistency Testing indicated that the ISV product has excellent characteristics relative to other vitreous nuclear waste forms

  19. Formation of Cu{sub 2}SnSe{sub 3} from stacked elemental layers investigated by combined in situ X-ray diffraction and differential scanning calorimetry techniques

    Energy Technology Data Exchange (ETDEWEB)

    Wibowo, Rachmat Adhi, E-mail: wibowo@krist.uni-erlangen.de [Chair for Crystallography and Structure Physics, University of Erlangen-Nürnberg, Staudtstr. 3, 91058 Erlangen (Germany); Moeckel, Stefan [Department of Materials Science, University of Erlangen-Nürnberg, Martenstr. 9, 91058 Erlangen (Germany); Yoo, Hyesun; Hoelzing, Astrid; Hock, Rainer [Chair for Crystallography and Structure Physics, University of Erlangen-Nürnberg, Staudtstr. 3, 91058 Erlangen (Germany); Wellmann, Peter J. [Department of Materials Science, University of Erlangen-Nürnberg, Martenstr. 9, 91058 Erlangen (Germany)

    2014-03-05

    Highlights: • In situ investigation revealed intermetallic compounds and Cu{sub 2}SnSe{sub 3} formations. • CuSe phase dominates binary phase formations at a low annealing temperature. • SnSe forms from liquid phase reaction of Sn and Se. • Binary Cu-selenide phase exerts sequential phase decompositions. • Crystalline Cu{sub 2}SnSe{sub 3} forms above 450 °C. -- Abstract: Stacked elemental layers of Mo/Cu/Sn and Mo/Cu/Sn/Se were employed as samples for investigating the formation reaction of Cu–Sn intermetallic compounds as well as Cu{sub 2}SnSe{sub 3} phases by in situ technique of X-ray diffraction and differential scanning calorimetry. The use of a combined in situ technique allows a real-time observation on solid-state reactions as well as any crystalline phase changes during annealing towards the crystallization of Cu{sub 2}SnSe{sub 3}. It is found that Cu and Sn form intermetallic compounds of Cu{sub 6}Sn{sub 5}, Cu{sub 3}Sn and Cu{sub 41}Sn{sub 11} as the annealing temperature rises from 30 to 550 °C. The reaction of Se with Cu to form a CuSe phase dominates the binary phase formation at a low annealing temperature. The annealing of a stacked Mo/Cu/Sn/Se layer suggests that only Cu{sub 6}Sn{sub 5} intermetallic compound directly acts as a reactant for the Cu-selenide phase formation. A SnSe phase mostly forms from a liquid-state reaction of Sn and Se above the Sn melting point. The in situ investigation also reveals a complete set of Cu-selenide peritectic decompositions of CuSe{sub 2} ? CuSe ? Cu{sub 1.8}Se at 360 and 412 °C. The formation of Cu{sub 2}SnSe{sub 3} phase starts at 450 °C as a product from a reaction between Cu{sub 1.8}Se and SnSe in a presence of liquid Se. Comparisons on the initial formation temperatures of all involved phases and on the formation pathways between Cu{sub 2}SnSe{sub 3} and Cu{sub 2}SnS{sub 3} are discussed as well.

  20. Aplicaciones e inconvenientes de la técnica Hibridación in situ Fluorescente (FISH) en la identificación de microorganismos / Applications and inconvenient of Fluorescence in situ hybridization technique (FISH) in the identification of microorganism

    Scientific Electronic Library Online (English)

    Raúl, Rodríguez Martínez; Gina, Suescún Otero.

    2013-05-01

    Full Text Available Durante el transcurso de los últimos años se ha reportado un gran número de aplicaciones de la técnica FISH, la cual es utilizada en la detección de microorganismos en su propio hábitat sin que requieran de su previo aislamiento y purificación. La importancia de FISH radica en la capacidad que tiene [...] la sonda de ADN de detectar una región específica del ácido nucleico de la célula microbiana y ser visualizada por microscopía de epifluorescencia. En esta revisión se describe los diversos usos que tiene FISH, que van desde la identificación de la microbiota en ambientes acuáticos y su empleo en la biorremediación hasta la detección de patógenos en el diagnóstico clínico. Asimismo, se presentan algunas limitaciones, y los posibles correctivos que se deben tener encuenta cuando se aplica esta técnica. Abstract in english During these recent years, a large number of FISH technique applications have been reported. These techniques have been used in the detection of microorganisms in their own habitat without requiring their previous isolation and purification. The importance of FISH lies in the ability of the DNA prob [...] e to detect a specific region of the nucleic acid of microbial cells and to be visualized by epifluorescence microscopy. This review describes the various FISH uses ranging from the identification of the microbiota in aquatic environments and their use in bioremediation, to the detection of pathogens in clinical diagnosis. It also presents some limitations as well as the potential solutions to be applied when the FISH technique is used.

  1. In-situ and Remote-Sensing Data Fusion Using Machine Learning Techniques to Infer Urban and Fire Related Pollution Plumes

    Science.gov (United States)

    Segal-Rosenhaimer, M.; Russell, P. B.; Schmid, B.; Redemann, J.; Livingston, J. M.; Flynn, C. J.; Johnson, R. R.; Dunagan, S. E.; Shinozuka, Y.; Kacenelenbogen, M. S.; Chatfield, R. B.

    2014-12-01

    Airmass type characterization is key in understanding the relative contribution of various emission sources to atmospheric composition and air quality and can be useful in bottom-up model validation and emission inventories. However, classification of pollution plumes from space is often not trivial. Sub-orbital campaigns, such as SEAC4RS (Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys) give us a unique opportunity to study atmospheric composition in detail, by using a vast suite of in-situ instruments for the detection of trace gases and aerosols. These measurements allow identification of spatial and temporal atmospheric composition changes due to various pollution plumes resulting from urban, biogenic and smoke emissions. Nevertheless, to transfer the knowledge gathered from such campaigns into a global spatial and temporal context, there is a need to develop workflow that can be applicable to measurements from space. In this work we rely on sub-orbital in-situ and total column remote sensing measurements of various pollution plumes taken aboard the NASA DC-8 during 2013 SEAC4RS campaign, linking them through a neural-network (NN) algorithm to allow inference of pollution plume types by input of columnar aerosol and trace-gas measurements. In particular, we use the 4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research) airborne measurements of wavelength dependent aerosol optical depth (AOD), particle size proxies, O3, NO2 and water vapor to classify different pollution plumes. Our method relies on assigning a-priori "ground-truth" labeling to the various plumes, which include urban pollution, different fire types (i.e. forest and agriculture) and fire stage (i.e. fresh and aged) using cluster analysis of aerosol and trace-gases in-situ and expert input and the training of a NN scheme to fit the best prediction parameters using 4STAR measurements as input. We explore our misclassification rates as related to our "ground-truth" labels, and with multi-layered pollution plume cases. The next step in our analysis is to optimize parameter selection for a scheme that can be applied to space-borne aerosol and trace-gas observation platforms such as OMI, and future geostationary satellites such as TEMPO and GEO-CAPE.

  2. In-Situ Measurements of Aerosol Optical Properties using New Cavity Ring-Down and Photoacoustics Instruments and Comparison with more Traditional Techniques

    Science.gov (United States)

    Strawa, A. W.; Arnott, P.; Covert, D.; Elleman, R.; Ferrare, R.; Hallar, A. G.; Jonsson, H.; Kirchstetter, T. W.; Luu, A. P.; Ogren, J.

    2004-01-01

    Carbonaceous species (BC and OC) are responsible for most of the absorption associated with aerosol particles. The amount of radiant energy an aerosol absorbs has profound effects on climate and air quality. It is ironic that aerosol absorption coefficient is one of the most difficult aerosol properties to measure. A new cavity ring-down (CRD) instrument, called Cadenza (NASA-ARC), measures the aerosol extinction coefficient for 675 nm and 1550 nm light, and simultaneously measures the scattering coefficient at 675 nm. Absorption coefficient is obtained from the difference of measured extinction and scattering within the instrument. Aerosol absorption coefficient is also measured by a photoacoustic (PA) instrument (DRI) that was operated on an aircraft for the first time during the DOE Aerosol Intensive Operating Period (IOP). This paper will report on measurements made with this new instrument and other in-situ instruments during two field recent field studies. The first field study was an airborne cam;oaign, the DOE Aerosol Intensive Operating Period flown in May, 2003 over northern Oklahoma. One of the main purposes of the IOP was to assess our ability to measure extinction and absorption coefficient in situ. This paper compares measurements of these aerosol optical properties made by the CRD, PA, nephelometer, and Particle Soot Absorption Photometer (PSAP) aboard the CIRPAS Twin-Otter. During the IOP, several significant aerosol layers were sampled aloft. These layers are identified in the remote (AATS-14) as well as in situ measurements. Extinction profiles measured by Cadenza are compared to those derived from the Ames Airborne Tracking Sunphotometer (AATS-14, NASA-ARC). The regional radiative impact of these layers is assessed by using the measured aerosol optical properties in a radiative transfer model. The second study was conducted in the Caldecott Tunnel, a heavily-used tunnel located north of San Francisco, Ca. The aerosol sampled in this study was characterized by fresh automobile and diesel exhaust. Measurements from Cadenza and from an aethalometer are presented. The aethalometer is a filter-based photometer and the infrared channel is calibrated to produce a measure of BC mass loading.

  3. Stabilization of the total force in multi-finger pressing tasks studied with the ‘inverse piano’ technique

    OpenAIRE

    Martin, J. R.; Budgeon, M. K.; Zatsiorsky, V. M.; Latash, M. L.

    2011-01-01

    When one finger changes its force, other fingers of the hand can show unintended force changes in the same direction (enslaving) and in the opposite direction (error compensation). We tested a hypothesis that externally imposed changes in finger force predominantly lead to error compensation effects in other fingers thus stabilizing the total force. A novel device, the “inverse piano”, was used to impose controlled displacements to one of the fingers over different magnitudes and at diffe...

  4. Mechanical resistance of the modified stabilization method for the tibial tuberosity advancement technique: ex vivo experimental study in dogs Resistência mecânica da técnica de avanço da tuberosidade tibial modificada: estudo experimental ex vivo em cães

    OpenAIRE

    Bruno Testoni Lins; Sheila Canevese Rahal; Mário Jefferson Louzada; José Carlos Dalmas; André Luis Selmi

    2009-01-01

    The present study aimed to evaluate a modification of the stabilization method of the tibial tuberosity advancement technique (TTA), originally described for stabilization of the cranial cruciate deficient stifle. Ten adult mongrel dogs with weights ranging from 25 to 30kg were used. After euthanasia, the hind-limbs were divided into two groups: G1 - test (n=10), and G2 - control (n=10) represented by the contra lateral limb. The test group was submitted to the modified TTA technique, stabili...

  5. Study and applications of XRF measuring technique in-situ for gold exploration in the periphery of the manaoke gold mine

    International Nuclear Information System (INIS)

    Characteristics of the XRF anomalies above the known golden ore body have been studied in the periphery of the Manaoke Gold Mine. By multi-element XRF measurement in-situ in soil, four As, Cu, Pb, Zn, Sr composite anomalies have acquired rapidly. On the basis of Characteristics of the XRF anomalies, the nature of the all of the XRF anomalies have been affirmed, and the two new target areas of golden exploration have been defined. Be analysis of the sampled soil in the new target areas, it is indicated that the golden content of great majority of soil samples are above the background. The highest golden content is 290 x 10-9, and is more 100 times than the background. It is indicated incontestably that the XRF anomalies in new target areas are the anomalies of golden ore body. (authors)

  6. Final report, Ames Mobile Laboratory Project: The development and operation of instrumentation in a mobile laboratory for in situ, real-time screening and characterization of soils using the laser ablation sampling technique

    International Nuclear Information System (INIS)

    The main focus of the Ames Laboratory's Technology Integration Program, TIP, from May 1991 through December 1994 was the development, fabrication, and demonstration of a mobile instrumentation laboratory incorporating rapid in situ sampling systems for safe, rapid, and cost effective soil screening/characterization. The Mobile Demonstration Laboratory for Environmental Screening Technologies, MDLEST, containing the analysis instrumentation, along with surface and subsurface sampling probe prototypes employing the laser ablation sampling technique were chosen to satisfy the particular surface and subsurface soil characterization needs of the various Department of Energy facilities for determining the extent of heavy metal and radionuclide contamination. The MDLEST, a 44 foot long 5th wheel trailer, is easily configured for the analysis instrumentation and sampling system required for the particular site work. This mobile laboratory contains all of the utilities needed to satisfy the operating requirements of the various instrumentation installed. These utilities include, an electric generator, a chilled water system, process gases, a heating/air conditioning system, and computer monitoring and automatic operating systems. Once the MDLEST arrives at the job site, the instrumentation is aligned and calibration is completed, sampling and analysis operations begin. The sample is acquired, analyzed and the results reported in as little as 10 minutes. The surface sampling probe is used in two modes to acquire samples for analysis. It is either set directly on the ground over the site to be sampled, in situ sampling, or in a special fixture used for calibrating the sampling analysis system with standard soil samples, having the samples brought to the MDLEST. The surface sampling probe was used to in situ sample a flat concrete surface (nondestructively) with the ablated sample being analyzed by the instrumentation in the MDLEST

  7. On the Application of a Response Surface Technique to Analyze Roll-over Stability of Capsules with Airbags Using LS-Dyna

    Science.gov (United States)

    Horta, Lucas G.; Reaves, Mercedes C.

    2008-01-01

    As NASA moves towards developing technologies needed to implement its new Exploration program, studies conducted for Apollo in the 1960's to understand the rollover stability of capsules landing are being revisited. Although rigid body kinematics analyses of the roll-over behavior of capsules on impact provided critical insight to the Apollo problem, extensive ground test programs were also used. For the new Orion spacecraft being developed to implement today's Exploration program, new air-bag designs have improved sufficiently for NASA to consider their use to mitigate landing loads to ensure crew safety and to enable re-usability of the capsule. Simple kinematics models provide only limited understanding of the behavior of these air bag systems, and more sophisticated tools must be used. In particular, NASA and its contractors are using the LS-Dyna nonlinear simulation code for impact response predictions of the full Orion vehicle with air bags by leveraging the extensive air bag prediction work previously done by the automotive industry. However, even in today's computational environment, these analyses are still high-dimensional, time consuming, and computationally intensive. To alleviate the computational burden, this paper presents an approach that uses deterministic sampling techniques and an adaptive response surface method to not only use existing LS-Dyna solutions but also to interpolate from LS-Dyna solutions to predict the stability boundaries for a capsule on airbags. Results for the stability boundary in terms of impact velocities, capsule attitude, impact plane orientation, and impact surface friction are discussed.

  8. Ionization constants and thermal stabilities of uracil and adenine under hydrothermal conditions as measured by in situ UV-visible spectroscopy

    Science.gov (United States)

    Balodis, Erik; Madekufamba, Melerin; Trevani, Liliana N.; Tremaine, Peter R.

    2012-09-01

    UV-visible spectra for aqueous uracil and adenine were measured in a high-pressure platinum flow cell with sapphire windows at temperatures up to 250 °C at a constant pressure of 7.2 MPa. Ionization constants were determined from pH-dependent spectra in the buffer solutions NH3/NH4Cl, NaHCO3/Na2CO3, HCOOH/NaHCOO and NaH2PO4/Na2HPO4. Variations in the spectra with pH and temperature at constant flow rate were used to determine the first ionization constant of uracil, K1a (uracil), and the first and second acid ionization constants of adenine, K1a (adenine) and K2a (adenine), at ionic strength I = 0.2 mol kg-1 and temperatures up to 200 °C. Time-dependent spectra, obtained by operating the cell as a stopped flow reactor, were used to examine the rate of thermal decomposition as a function of temperature and pH from 200 to 250 °C. Reaction pathways and rate constants were determined by singular value decomposition methods. Uracil and adenine decomposition occurred by one-step and two-step processes, respectively. The kinetic results in the NaH2PO4/Na2HPO4 buffer solution are in quantitative agreement with the less-extensive pioneering study by White (Nature 310, 430-432 (1984)), but differ from results in buffers that do not contain phosphate, suggesting that phosphate enhances the thermal stability of nucleic acid bases.

  9. In situ stabilization of chromium(VI) in polluted soils using organic ligands: the role of galacturonic, glucuronic and alginic acids.

    Science.gov (United States)

    Kantar, Cetin; Cetin, Zeynep; Demiray, Hilal

    2008-11-30

    Laboratory batch sorption and column experiments were performed to investigate the role of organic ligands such as galacturonic, glucuronic and alginic acids (main constituents of bacterial exopolymeric substances (EPS)) on Cr(VI) uptake and transport in heterogeneous subsurface media. Our batch sorption experiments demonstrate the addition of galacturonic, glucuronic and alginic acids to soils enhances Cr(VI) uptake by soil at pH values <7.7 depending on the concentration of the ligand and pH used. The enhanced Cr(VI) uptake at pH values <7.7 may be explained through either the catalytic reduction of Cr(VI) to Cr(III) by the surface-bound organic matter/Fe oxides and/or the dissolved metal ions (e.g., Fe(III)) from the soil. On the other hand, organic ligands have no or little effect on Cr(VI) uptake under highly alkaline pH conditions since the catalytic Cr(VI) reduction decreases with increasing pH. Similarly, the results from column experiments show that, depending on the concentration of organic ligands, the Cr(VI) breakthrough curves were significantly retarded relative to the organic acid-free systems at pH 7.6. A significant portion of Cr(VI) initially added to the feed solution was not readily recoverable in the effluent, indicating Cr(VI) reduction in columns, most probably catalyzed by surface-bound metal-oxides (e.g., Fe oxides) or dissolved metal ions such as Fe(II; III). The overall results suggest that EPS constituents such as glucuronic, galacturonic and alginic acids may play a significant role on Cr(VI) stabilization in subsurface systems under acidic to slightly alkaline pH conditions. PMID:18387738

  10. Taming the rugged energy landscape Techniques for the production, reordering, and stabilization of selected cluster inherent structures

    CERN Document Server

    Sabo, D; Freeman, D L; Sabo, Dubravko; Freeman, David L.

    2003-01-01

    We report our studies of the potential energy surface (PES) of selected binary Lennard-Jones clusters. The effect of adding selected impurity atoms to a homogeneous cluster is explored. Inherent structures and transition states are found by combination of conjugate-gradient and eigenvector-following methods while the topography of the PES is mapped with the help of a disconnectivity analysis. We show that we can controllably induce new structures as well as reorder and stabilize existing structures that are characteristic of higher-lying minima.

  11. A review of joining techniques for SiC{sub f}/SiC composites for first wall applications

    Energy Technology Data Exchange (ETDEWEB)

    Lewinsohn, C.A.; Jones, R.H. [Pacific Northwest National Lab., Richland, WA (United States)

    1998-09-01

    Many methods for joining monolithic and composite silicon carbide are available. Three techniques are candidates for use in fusion energy systems: in-situ displacement reactions, pre-ceramic polymer adhesives, and reaction bonding. None of the methods are currently developed enough to satisfy all of the criteria required, i.e., low temperature fabrication, high strength, and radiation stability. 58 refs.

  12. Performance and durability of Pt/C cathode catalysts with different kinds of carbons for polymer electrolyte fuel cells characterized by electrochemical and in situ XAFS techniques.

    Science.gov (United States)

    Nagasawa, Kensaku; Takao, Shinobu; Higashi, Kotaro; Nagamatsu, Shin-ichi; Samjeské, Gabor; Imaizumi, Yoshiaki; Sekizawa, Oki; Yamamoto, Takashi; Uruga, Tomoya; Iwasawa, Yasuhiro

    2014-06-01

    The electrochemical activity and durability of Pt nanoparticles on different kinds of carbon supports in oxygen reduction reactions (ORR) were investigated using rotating disc electrodes (RDE) and the membrane electrode assemblies (MEA) of polymer electrolyte fuel cells (PEFC). The mass activity of Pt/C catalysts (ORR activity per 1 mg of Pt) at the RDE decreased, according to the type of carbon support, in the following order; Ketjenblack (KB) > acetylene black (AB) > graphene > multiwall carbon nanotube (MW-CNT) > carbon black (CB), whereas the average size of the Pt nanoparticles and the surface specific activity (ORR activity per electrochemical surface area) did not vary significantly between these carbon supports. These results indicate that the different mass activities of the Pt/C catalysts may originate from the differences in the fraction of Pt on the carbon supports which is available for utilization. The durability of the MEAs of the top two active catalysts Pt/KB and Pt/AB among the five catalysts was examined based on ORR performance, TEM and in situ XAFS. It was found that the performance of the Pt/KB cathode catalyst in PEFC MEA decreased significantly over 500 accelerated durability test (ADT) cycles, whereas the performance of the Pt/AB cathode catalyst in PEFC MEA did not decrease significantly during 500 ADT cycles, it was also found that the Pt/AB possesses 8 times higher durability compared with the Pt/KB. In situ Pt LIII-edge XAFS data in the ADT cycles and stepwise potential operations revealed the different oxidation-reduction behaviors of the Pt nanoparticles on the KB and AB supports. The Pt/KB was oxidized to form surface PtO layers more easily than the Pt/AB in the increasing potential operation from 0.4 VRHE to 1.4 VRHE, and the surface PtO layers of the Pt/AB were reduced to the metallic Pt state more readily than those of the Pt/KB in the decreasing potential operation from 1.4 VRHE to 0.4 VRHE. The XAFS analysis for the Pt valences and the coordination numbers of Pt-O and Pt-Pt demonstrated that the Pt/AB catalyst is more durable than the Pt/KB catalyst in PEFC MEAs. PMID:24513596

  13. Stability-indicating micellar electrokinetic chromatography technique for simultaneous measurement of delapril and manidipine from a combination drug formulation.

    Science.gov (United States)

    Todeschini, Vítor; Sangoi, Maximiliano da Silva; Meira, Alianise da Silva; Miron, Diogo; Lange, Alini Dall Cortivo; Volpato, Nadia Maria

    2014-01-01

    A stability-indicating micellar electrokinetic chromatography (MEKC) method was developed and validated for simultaneous analysis of delapril (DEL) and manidipine (MAN) using salicylic acid as an internal standard. The MEKC method was performed using a fused-silica capillary (effective length of 72 cm) with 50 mM of borate buffer and 5 mM of anionic surfactant sodium dodecylsulfate at pH 9.0 as the background electrolyte. The separation was achieved at 25 kV applied voltage and 35 degrees C. The injection was performed at 50 mbar for 5 s, with detection at 208 nm. The method was linear in the range of 15-150 microg/mL (r2 = 0.9966) for DEL and 5-50 microg/mL (r2 = 0.9985) for MAN with adequate results for the precision (< or = 1.87%) and accuracy (98.94% for DEL and 100.65% for MAN). The specificity of the method and its stability-indicating capability was demonstrated through forced degradation studies, which showed that there was no interference from the excipients. The Plackett-Burman experimental design was used for robustness evaluation, giving results within the acceptable range. The method was successfully applied for analysis of the drugs, and the results were compared to an LC method, resulting in nonsignificant differences (P = 0.78 and 0.84 for DEL and MAN, respectively). PMID:24672867

  14. Stabilization of the total force in multi-finger pressing tasks studied with the 'inverse piano' technique.

    Science.gov (United States)

    Martin, J R; Budgeon, M K; Zatsiorsky, V M; Latash, M L

    2011-06-01

    When one finger changes its force, other fingers of the hand can show unintended force changes in the same direction (enslaving) and in the opposite direction (error compensation). We tested a hypothesis that externally imposed changes in finger force predominantly lead to error compensation effects in other fingers thus stabilizing the total force. A novel device, the "inverse piano", was used to impose controlled displacements to one of the fingers over different magnitudes and at different rates. Subjects (n=10) pressed with four fingers at a constant force level and then one of the fingers was unexpectedly raised. The subjects were instructed not to interfere with possible changes in the finger forces. Raising a finger caused an increase in its force and a drop in the force of the other three fingers. Overall, total force showed a small increase. Larger force drops were seen in neighbors of the raised finger (proximity effect). The results showed that multi-finger force stabilizing synergies dominate during involuntary reactions to externally imposed finger force changes. Within the referent configuration hypothesis, the data suggest that the instruction "not to interfere" leads to adjustments of the referent coordinates of all the individual fingers. PMID:21450360

  15. Stabilization of the total force in multi-finger pressing tasks studied with the ‘inverse piano’ technique

    Science.gov (United States)

    Martin, J.R.; Budgeon, M.K.; Zatsiorsky, V.M.; Latash, M.L.

    2010-01-01

    When one finger changes its force, other fingers of the hand can show unintended force changes in the same direction (enslaving) and in the opposite direction (error compensation). We tested a hypothesis that externally imposed changes in finger force predominantly lead to error compensation effects in other fingers thus stabilizing the total force. A novel device, the “inverse piano”, was used to impose controlled displacements to one of the fingers over different magnitudes and at different rates. Subjects (n =10) pressed with four fingers at a constant force level and then one of the fingers was unexpectedly raised. The subjects were instructed not to interfere with possible changes in the finger forces. Raising a finger caused an increase in its force and a drop in the force of the other three fingers. Overall, total force showed a small increase. Larger force drops were seen in neighbors of the raised finger (proximity effect). The results show that multi-finger force stabilizing synergies dominate during involuntary reactions to externally imposed finger force changes. Within the referent configuration hypothesis, the data suggest that the instruction “not to interfere” leads to adjustments of the referent coordinates of all the individual fingers. PMID:21450360

  16. Research and development of treatment techniques for LLW from decommissioning: Decontamination and volume reduction techniques

    International Nuclear Information System (INIS)

    For the purpose of reducing the amount and/or volume of low-level radioactive waste (LLW) arising from decommissioning of nuclear reactor, the Japan Atomic Energy Research Institute (JAERI) has been developing four decontamination techniques. They are: (a) Gas-carrying abrasive method, (b) In-situ remote electropolishing method for pipe system before dismantling, (c) Bead reaction - thermal shock method, and (d) Laser induced chemical method for components after dismantling. JAERI in developing techniques are also carrying out melting tests of metal and non-metal. Melting was confirmed to be effective in reducing the volume, homogenizing, and furthermore stabilizing non-metallic wastes. (author)

  17. In situ investigation of the surface silvering of late Roman coins by combined use of high energy broad-beam and low energy micro-beam X-ray fluorescence techniques

    International Nuclear Information System (INIS)

    The compositional analysis of archeological metals performed with the X-ray Fluorescence technique (XRF) provides information on the ancient technology. One of the most interesting case-study concerns the techniques used by Romans for silvering the surface of coins. Different metallurgical processes have been suggested in previous studies. Recently the investigation has been addressed to the mercury-silvering and to its possible use in the mass-production of coins minted during the late period (after 294 AD). In the present paper the non-destructive investigation of the silvering process used for manufacturing the Roman nummi – the important typology of coin introduced by Diocletian in his monetary reform – is approached by the combined use of the standard X-Ray Fluorescence (XRF) and the low energy micro-X-Ray Fluorescence (LE-?XRF) portable methods. The research was focused on the systematic determination of the mercury presence in a large number of samples and on its correlation with silver in the surface of the coins. 1041 Roman nummi belonging to the Misurata Treasure were analyzed in situ, at the Leptis Magna Museum (Al Khums, Libya). The treasure, composed of about 108 thousand silvered coins, gives the unique opportunity to study the Roman coinage in a wide interval of time (about 40 years in the period 294–333 AD) and in almost all the imperial mints operating in the Roman world. - Highlights: ? Custom-building of a high energy broad-beam and a low eigh energy broad-beam and a low energy micro-beam XRF ? In situ analysis of the silvering methods in late Roman nummi with plated surfaces ? The broad-beam XRF was applied for the detection of mercury traces in the coin alloy. ? The low energy micro-XRF was used to scan the surface patina of the coins. ? The correlation between mercury and silver at the coin surface was evidenced.

  18. Charge collection microscopy of in-situ switchable PRAM line cells in a scanning electron microscope: Technique development and unique observations

    Science.gov (United States)

    Oosthoek, J. L. M.; Schuitema, R. W.; ten Brink, G. H.; Gravesteijn, D. J.; Kooi, B. J.

    2015-03-01

    An imaging method has been developed based on charge collection in a scanning electron microscope (SEM) that allows discrimination between the amorphous and crystalline states of Phase-change Random Access Memory (PRAM) line cells. During imaging, the cells are electrically connected and can be switched between the states and the resistance can be measured. This allows for electrical characterization of the line cells in-situ in the SEM. Details on sample and measurement system requirements are provided which turned out to be crucial for the successful development of this method. Results show that the amorphous or crystalline state of the line cells can be readily discerned, but the spatial resolution is relatively poor. Nevertheless, it is still possible to estimate the length of the amorphous mark, and also for the first time, we could directly observe the shift of the amorphous mark from one side of the line cell to the other side when the polarity of the applied (50 ns) RESET pulse was reversed.

  19. Structural analysis on a block copolymer thin film by in-situ neutron and x-ray grazing-incidence scattering techniques

    International Nuclear Information System (INIS)

    Structural change of a phase-separated block copolymer thin film with polystyrene (PS) and poly(2-vinylpyridine)(P2VP) in contact with different solvents was observed by in-situ neutron reflectometry using a conventional cell for a solid/liquid interface, and time evolution of phase-separated structure after a temperature jump to 200degC was observed for diblock and triblock copolymer thin films of PS and P2VP by grazing-incidence small-angle X-ray scattering (GISAXS). When PS-P2VP diblock copolymer thin film was contacted with methanol and water, the structural change was induced by penetration of small amount of the solvent into the film, and the original structure was almost recovered after drying it. Also, the diblock copolymer thin film was easily dissolved into toluene, and the original structure was never recovered after the solvent contact. After the temperature jump the lateral correlation spots were evolved with a time in the GISAXS pattern similarly for either block copolymer thin film with spherical structure, though their as-spun states were different. (author)

  20. Use of thermal analysis techniques (TG–DSC) for the characterization of diverse organic municipal waste streams to predict biological stability prior to land application

    International Nuclear Information System (INIS)

    Highlights: ? Thermal analysis was used to assess stability and composition of organic matter in three diverse municipal waste streams. ? Results were compared with C mineralization during 90-day incubation, FTIR and 13C NMR. ? Thermal analysis reflected the differences between the organic wastes before and after the incubation. ? The calculated energy density showed a strong correlation with cumulative respiration. ? Conventional and thermal methods provide complimentary means of characterizing organic wastes. - Abstract: The use of organic municipal wastes as soil amendments is an increasing practice that can divert significant amounts of waste from landfill, and provides a potential source of nutrients and organic matter to ameliorate degraded soils. Due to the high heterogeneity of organic municipal waste streams, it is difficult to rapidly and cost-effectively establish their suitability as soil amendments using a single method. Thermal analysis has been proposed as an evolving technique to assess the stability and composition of the organic matter present in these wastes. In this study, three different organic municipal waste streams (i.e., a municipal waste compost (MC), a composted sewage sludge (CS) and a thermally dried sewage sludge (TS)) were characterized using conventional and thermal methods. The conventional methods used to test organic matter stability included laboratory incubation with measurement of respired C, and spectroscopi of respired C, and spectroscopic methods to characterize chemical composition. Carbon mineralization was measured during a 90-day incubation, and samples before and after incubation were analyzed by chemical (elemental analysis) and spectroscopic (infrared and nuclear magnetic resonance) methods. Results were compared with those obtained by thermogravimetry (TG) and differential scanning calorimetry (DSC) techniques. Total amounts of CO2 respired indicated that the organic matter in the TS was the least stable, while that in the CS was the most stable. This was confirmed by changes detected with the spectroscopic methods in the composition of the organic wastes due to C mineralization. Differences were especially pronounced for TS, which showed a remarkable loss of aliphatic and proteinaceous compounds during the incubation process. TG, and especially DSC analysis, clearly reflected these differences between the three organic wastes before and after the incubation. Furthermore, the calculated energy density, which represents the energy available per unit of organic matter, showed a strong correlation with cumulative respiration. Results obtained support the hypothesis of a potential link between the thermal and biological stability of the studied organic materials, and consequently the ability of thermal analysis to characterize the maturity of municipal organic wastes and composts.

  1. Development of an in-situ multi-component reinforced Al-based metal matrix composite by direct metal laser sintering technique — Optimization of process parameters

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Subrata Kumar, E-mail: subratagh82@gmail.com [Department of Mechanical Engineering, National Institute of Technology Agartala, Tripura 799055 (India); Bandyopadhyay, Kaushik; Saha, Partha [Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2014-07-01

    In the present investigation, an in-situ multi-component reinforced aluminum based metal matrix composite was fabricated by the combination of self-propagating high-temperature synthesis and direct metal laser sintering process. The different mixtures of Al, TiO{sub 2} and B{sub 4}C powders were used to initiate and maintain the self-propagating high-temperature synthesis by laser during the sintering process. It was found from the X-ray diffraction analysis and scanning electron microscopy that the reinforcements like Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were formed in the composite. The scanning electron microscopy revealed the distribution of the reinforcement phases in the composite and phase identities. The variable parameters such as powder layer thickness, laser power, scanning speed, hatching distance and composition of the powder mixture were optimized for higher density, lower porosity and higher microhardness using Taguchi method. Experimental investigation shows that the density of the specimen mainly depends upon the hatching distance, composition and layer thickness. On the other hand, hatching distance, layer thickness and laser power are the significant parameters which influence the porosity. The composition, laser power and layer thickness are the key influencing parameters for microhardness. - Highlights: • The reinforcements such as Al{sub 2}O{sub 3}, TiC, and TiB{sub 2} were produced in Al-MMC through SHS. • The density is mainly influenced by the material composition and hatching distance. • Hatching distance is the major influencing parameter on porosity. • The material composition is the significant parameter to enhance the microhardness. • The SEM micrographs reveal the distribution of TiC, TiB{sub 2} and Al{sub 2}O{sub 3} in the composite.

  2. Development of an in-situ multi-component reinforced Al-based metal matrix composite by direct metal laser sintering technique — Optimization of process parameters

    International Nuclear Information System (INIS)

    In the present investigation, an in-situ multi-component reinforced aluminum based metal matrix composite was fabricated by the combination of self-propagating high-temperature synthesis and direct metal laser sintering process. The different mixtures of Al, TiO2 and B4C powders were used to initiate and maintain the self-propagating high-temperature synthesis by laser during the sintering process. It was found from the X-ray diffraction analysis and scanning electron microscopy that the reinforcements like Al2O3, TiC, and TiB2 were formed in the composite. The scanning electron microscopy revealed the distribution of the reinforcement phases in the composite and phase identities. The variable parameters such as powder layer thickness, laser power, scanning speed, hatching distance and composition of the powder mixture were optimized for higher density, lower porosity and higher microhardness using Taguchi method. Experimental investigation shows that the density of the specimen mainly depends upon the hatching distance, composition and layer thickness. On the other hand, hatching distance, layer thickness and laser power are the significant parameters which influence the porosity. The composition, laser power and layer thickness are the key influencing parameters for microhardness. - Highlights: • The reinforcements such as Al2O3, TiC, and TiB2 were produced in Al-MMC throu. • The density is mainly influenced by the material composition and hatching distance. • Hatching distance is the major influencing parameter on porosity. • The material composition is the significant parameter to enhance the microhardness. • The SEM micrographs reveal the distribution of TiC, TiB2 and Al2O3 in the composite

  3. Development and Testing of Techniques for In-Ground Stabilization, Size Reduction and Safe Removal of Radioactive Wastes Stored in Large Containments in Burial Grounds - 13591

    International Nuclear Information System (INIS)

    Radioactive waste materials, including Transuranic (TRU) wastes from laboratories have been stored below ground in large containments at a number of sites in the US DOE Complex, and at nuclear sites in Europe. These containments are generally referred to as caissons or shafts. The containments are in a range of sizes and depths below grade. The caissons at the DOE's Hanford site are cylindrical, of the order of 2,500 mm in diameter, 3,050 mm in height and are buried about 6,000 mm below grade. One type of caisson is made out of corrugated pipe, whereas others are made of concrete with standard re-bar. However, the larger shafts in the UK are of the order of 4,600 mm in diameter, 53,500 mm deep, and 12,000 below grade. This paper describes the R and D work and testing activities performed to date to evaluate the concept of in-ground size reduction and stabilization of the contents of large containments similar to those at Hanford. In practice, the height of the Test Facility provided for a test cell that was approximately 22' deep. That prevented a 'full scale mockup' test in the sense that the Hanford Caisson configuration would be an identical replication. Therefore, the project was conducted in two phases. The first phase tested a simulated Caisson with surrogate contents, and part of a Chute section, and the second phase tested a full chute section. These tests were performed at VJ Technologies Test Facility located in East Haven, CT, as part of the Proof of Design Concept program for studying the feasibility of an in-situ grout/grind/mix/stabilize technology for the remediation of four caissons at the 618-11 Burial Ground at US Department of Energy Hanford Site. The test site was constructed such that multiple testing areas were provided for the evaluation of various tools, equipment and procedures under conditions that simulated the Hanford site, with representative soils and layout dimensions. (authors)

  4. Accuracy assessment of water vapour measurements from in-situ and remote sensing techniques during the DEMEVAP 2011 campaign at OHP

    OpenAIRE

    Bock, O; Bosser, P.; Bourcy, T.; David, L.; Goutail, F.; Hoareau, C.; Keckhut, P.; Legain, D.; Pazmino, A.; Pelon, J.; K. Pipis; Poujol, G.; SARKISSIAN, A.; Thom, C; Tournois, G.

    2013-01-01

    The Development of Methodologies for Water Vapour Measurement (DEMEVAP) project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems....

  5. In-situ solidification of low and medium level wastes

    International Nuclear Information System (INIS)

    The in-situ concept as developed represents an alternative disposal concept to the currently demonstrated drum-disposal technique. Only significant advantages with respect to safe operation, health and safety, and economic benefit can justify the R and D efforts already spent since 1976 and to be spent tin the third forthcoming project phase. The drum disposal technique requires much more open cavern volume (up to a factor of 6), which must be stable for a perod of operation of at least 50 yr. The stability requirements for such a large man-operated mine are considered to be much more stringent than for an anticipated in-situ cavern volume of 75,000 m3, which will be ompletely backfilled with a stable waste monolith after only five years. A backfilled in-situ cavern restabilizes the geological strata and stops convergence movements; however, convergence is a very positive factor, for it closes all gaps between the monolith and the salt formation so that no liquid can move along this interface and potentially carry activity. A filled and sealed cavern needs no more surveillance. Even during the time of operation, water intrusions do not pose major problems. Calculations of the activity releases into groundwater tables with contaminated brine solutions from the flooded in-situ cavern did not show groundwater contamination above MPC levels beyond a distance of 300 m from the borehole. As a further remedial action it is feasible, after a water inrush, to overca feasible, after a water inrush, to overcast the waste product in the cavern with a layer of insoluble matter, such as bentonite, which will result in a very long term diffusion process for the underlying activity. This layer further reduces groundwater contamination by several orders of magnitude in case of this very improbable accident

  6. In-situ characterization of heterogeneous catalysts

    CERN Document Server

    Rodriguez, Jose A; Chupas, Peter J

    2013-01-01

    Helps researchers develop new catalysts for sustainable fuel and chemical production Reviewing the latest developments in the field, this book explores the in-situ characterization of heterogeneous catalysts, enabling readers to take full advantage of the sophisticated techniques used to study heterogeneous catalysts and reaction mechanisms. In using these techniques, readers can learn to improve the selectivity and the performance of catalysts and how to prepare catalysts as efficiently as possible, with minimum waste. In-situ Characterization of Heterogeneous Catalysts feat

  7. Acute promyelocytic leukemia: the study of t(15;17) translocation by fluorescent in situ hybridization, reverse transcriptase-polymerase chain reaction and cytogenetic techniques

    Scientific Electronic Library Online (English)

    M.L.L.F., Chauffaille; M.S., Figueiredo; R., Beltrani; S.V., Antunes; M., Yamamoto; J., Kerbauy.

    2001-06-01

    Full Text Available Acute promyelocytic leukemia (AML M3) is a well-defined subtype of leukemia with specific and peculiar characteristics. Immediate identification of t(15;17) or the PML/RARA gene rearrangement is fundamental for treatment. The objective of the present study was to compare fluorescent in situ hybridiz [...] ation (FISH), reverse transcriptase-polymerase chain reaction (RT-PCR) and karyotyping in 18 samples (12 at diagnosis and 6 after treatment) from 13 AML M3 patients. Bone marrow samples were submitted to karyotype G-banding, FISH and RT-PCR. At diagnosis, cytogenetics was successful in 10 of 12 samples, 8 with t(15;17) and 2 without. FISH was positive in 11/12 cases (one had no cells for analysis) and positivity varied from 25 to 93% (mean: 56%). RT-PCR was done in 6/12 cases and all were positive. Four of 8 patients with t(15;17) presented positive RT-PCR as well as 2 without metaphases. The lack of RT-PCR results in the other samples was due to poor quality RNA. When the three tests were compared at diagnosis, karyotyping presented the translocation in 80% of the tested samples while FISH and RT-PCR showed the PML/RARA rearrangement in 100% of them. Of 6 samples evaluated after treatment, 3 showed a normal karyotype, 1 persistence of an abnormal clone and 2 no metaphases. FISH was negative in 4 samples studied and 2 had no material for analysis. RT-PCR was positive in 4 (2 of which showed negative FISH, indicating residual disease) and negative in 2. When the three tests were compared after treatment, they showed concordance in 2 of 6 samples or, when there were not enough cells for all tests, concordance between karyotype and RT-PCR in one. At remission, RT-PCR was the most sensitive test in detecting residual disease, as expected (positive in 4/6 samples). An incidence of about 40% of 5' breaks and 60% of 3' breaks, i.e., bcr3 and bcr1/bcr2, respectively, was observed.

  8. Preparation and characterization of co-amorphous Ritonavir-Indomethacin systems by solvent evaporation technique: improved dissolution behavior and physical stability without evidence of intermolecular interactions.

    Science.gov (United States)

    Dengale, Swapnil J; Ranjan, Om Prakash; Hussen, Syed Sajjad; Krishna, B S M; Musmade, Prashant B; Gautham Shenoy, G; Bhat, Krishnamurthy

    2014-10-01

    The aim of this study was to stabilize the amorphous form of Ritonavir (RTV) a BCS class-II drug with known amorphous stabilizing small molecule Indomethacin (IND) by co-amorphous technology. The co-amorphous samples were prepared by solvent evaporation technique in the molar ratios RTV:IND (2:1), RTV:IND (1:1), RTV:IND (1:2) and their amorphous nature was confirmed by XRPD, DSC and FT-IR. Physical stability studies were carried out at temp 25°C and 40°C for maximum up to 90 days under dry conditions. Solubility and dissolution testing were carried out to investigate the dissolution advantage of prepared co-amorphous systems. The amorphous mixtures of all tested molar ratios were found to become amorphous after solvent evaporation. The same was confirmed by detecting halo pattern in diffractograms of co-amorphous mixtures. The Tg values of all three systems were found to be more than 40°C, the highest being 51.88°C for RTV:IND (2:1) system. Theoretical Tg values were calculated by Gordon-Taylor equation. Insignificant deviation of theoretical Tg values from that of practical one, corroborated by FT-IR studies showed no evidence of intermolecular interactions between RTV and IND. Almost 3-folds increase in the solubility for both amorphous RTV and IND was found as compared to their respective crystalline counterparts. The study demonstrated significant increase in the dissolution rate as well as increase in the total amount of drug dissolved for amorphous RTV, however it failed to demonstrate any significant improvement in the dissolution behavior of IND. PMID:24878386

  9. Ruminal Dry Matter and Crude Protein Degradability of Some Tropical (Iranian Feeds Used in Ruminant Diets Estimated Using the in situ and in vitro Techniques

    Directory of Open Access Journals (Sweden)

    2008-01-01

    Full Text Available The in situ ruminal dry matter (DM and crude protein (CP degradation and in vitro DM and CP disappearance of corn grain, soybean meal, wheat bran and alfalfa were compared. For in situ technique duplicate dacron bags were incubated for 0, 2, 4, 6, 8, 12, 16, 24, 36, 48, 72 and 96 h in two wethers fitted with ruminal cannulas. The in vitro degradability of DM and CP calculated at 0, 2, 12, 36 and 48 h incubation time for test feeds. The model of Ørskov and McDonald as y = a + b (1-e-ct was used for determination of degradation characteristics for both of methods. Wheat bran had higher soluble DM (a (30.3%, corn grain had higher insoluble potentially degradable DM (b (59.9% and soybean meal had higher degradation rate (9.67% h -1 than other feeds, inverses corn grain (14%, alfalfa (40.1% and alfalfa (3.40% h-1 had lower soluble DM, insoluble potentially degradable DM and degradation rate than other feeds, respectively. Wheat bran had higher soluble CP (a (33.3%, corn grain had higher insoluble potentially degradable CP (b (54.5% and soybean meal had higher degradation rate (9.78% h-1 than other feeds, inverses soybean meal (5.7%, alfalfa (43.9% and alfalfa (3.75% h-1 had lower soluble CP, insoluble potentially degradable CP and degradation rate than other feeds, respectively. There were differences (p<0.05 among test feeds in dry matter and crude protein degradability after several incubation times. There was strong coefficient of correlation between extent of in situ dry matter and crude protein degradation and in vitro dry matter and crude protein disappearance. The key protein parameters in the proposed Metabolizable protein system, quick digestible protein, slowly digestible protein and digestible undegradable protein are derived from measurements of the rates of degradation of feed proteins suspended in a dacron bag in the rumen. The Metabolizable protein of soybean meal (381 g kg-1 was numerically rather than the other feeds and for corn grain (86 g kg-1 was numerically less than the other feeds.

  10. Superconductivity of Bi2Sr2Can-1CunOy (n=2, 3, 4, and 5) thin films prepared in situ by molecular-beam epitaxy technique

    International Nuclear Information System (INIS)

    Preparation techniques and properties of Bi-Sr-Ca-Cu-O thin films are reported. The optimization of the substrate temperature in ozone atmosphere and the shuttering of molecular beams on an atomic scale enabled us to prepare thin films of Bi2Sr2Can-1CunOy (n=1, 2, 3, 4, and 5). These films showed superconducting transition with the exception of the n=1 phase and resistivities showed strong temperature dependence without heat treatment after deposition. Reflection high-energy electron diffraction showed sharp streaks, which suggest the growth of films with flat surface on an atomic scale

  11. Techniques and devices developed by the CEA for hot cell and in-situ examinations of PWR components and PWR fuel assembliess after irradiation

    International Nuclear Information System (INIS)

    Within the framework of the electro-nuclear development of the PWR system, the CEA has provided itself with facilities for developing techniques for analyzing assemblies, pins and fuels. These are examinations and tests on irradiated heads and assemblies with the aid of the Fuel Examination Module (FEM), of machining of assemblies and examinations in the Celimene hot laboratory or detailed examinations and analyses on fuel elements using eddy currents, the electronic microprobe and the Fisher ''permeascope'' which enables the outline of the oxide coat present on the cladding to be followed

  12. In Situ Characterization of Nuclear Energy Materials by Synchrotron Radiation and Electron Microscopy

    International Nuclear Information System (INIS)

    This paper presents the applications of in situ characterization techniques, including transmission electron microscopy (TEM) with in situ ion irradiation and high energy X ray diffraction with simultaneous thermal-mechanical loading, in the study of structural materials in advanced nuclear reactors. A good example cases is given here: a novel experiment of TEM with in situ ion irradiation of Mo thin films by 1 MeV Kr ion irradiation that was designed explicitly to improve and validate a computer model. A rate theory based cluster dynamic model was developed to model the ion irradiation induced damage in the thin film with temporal and spatial dependence of defect distribution. Experimental data were compared in detail with modelling results under exactly matched irradiation conditions. The interplay between experiments and modelling allowed an improved understanding of the physical process during irradiation and the development of an accurate physical model. Another area discussed is that of high energy X ray diffraction measurements of bulk materials under thermal/thermal-mechanical loading. This type of in situ characterization provides information on phase transformation and stability and the effect of microstructural changes on mechanical properties, essential to the development of predictive models of materials’ long term performance in nuclear reactor environments. Currently, an in situ radioactive materials probe is being developed for measuring irradiaterials under temperature and loading conditions. (author)

  13. The use of GPR technique in the slope stability survey at radar doppler terminal, Bukit Tampoi, Dengkil, Selangor

    International Nuclear Information System (INIS)

    A site investigation survey using GPR technique was carried out at Radar Doppler Terminal, Bukit Tampoi, Dengkil, and Selangor. The Terminal is situated approximately 10 km to the North of Kuala Lumpur International Airport. Geologically, the study area is located in the Kenny Hill formation consisting of low grade meta sedimentary rocks mainly of quartzite and phylline. A detailed geotechnical investigation at a cut slope of Kenny Hill formation in Selangor showed that the inter bedded rock mass is dominated by relatively thick sandstone with thin shale of slightly to highly weathered materials. The objective of study is to investigate any fractured or weak zone in the study area using the GPR technique. In this survey, 100 MHz frequency antenna model RAMAC/ GPR was used as a source to send the electromagnetic wave into the ground. A control unit (CUII) was used in monitoring the antenna via a laptop. A total of 25 parallel and vertical lines with 3 m-5 m spacing between each line were traversed in the study area. The maximum subsurface depth investigated was approximately 12 m. Reflected waves arrival between 0 m to 5 m depth in the radar gram section shows discontinuous, sub parallel and wavy patterns. These chaotic reflections patterns correspond to highly weathered silt with sandstone and gravel based on nearby borehole information as well as indicated by low SPT N-values of 0 to 13. For depth deeper than 5 m, the reflection pattern is dominated by high frequency parallel waveform that could be associated with stiff mud stone of 28-34 SPT N-values. The radar gram section also shows the presence of internal features in the meta sedimentary soils and rocks such as several small scale normal faults as well as sliding planes trending northwest-southeast in direction. (author)

  14. Modified stabilization method for the tibial tuberosity advancement technique: a biomechanical study Modificação da técnica de avanço da tuberosidade tibial: estudo biomecânico

    Directory of Open Access Journals (Sweden)

    Bruno Testoni Lins

    2009-04-01

    Full Text Available The present study aimed to determine biomechanical alterations resultant from a modification in the fixation method of the tibial tuberosity advancement technique (TTA, originally described for stabilization of the cranial cruciate-deficient stifle. Ten adult mongrel dogs weighing 25-30kg were used. After euthanasia, performed for reasons unrelated to this study, the hind limbs were distributed into two groups: G1 operated (n=10 and G2 control (n=10, represented by the contralateral limb. The operated hind limbs were orthopedically, goniometrically and radiographically evaluated, sequentially at four moments: moment 1, in intact joints; moment 2, after cranial cruciate desmotomy; moment 3, after surgical stabilization of the stifle joint using modified TTA; and moment 4, after caudal cruciate ligament desmotomy. The tibial tuberosity was stabilized by one shaft screw craniocaudally and a titanium cage inserted at the osteotomy site. The position of the patellar tendon at 90° in relation to the tibial plateau allowed cranial tibial thrust force neutralization, despite cranial drawer motion maintenance in all dogs. The biomechanical tests confirm the viability of the tibial tuberosity fixation method and support future clinical trials to validate the technique.O presente estudo teve como objetivo determinar as alterações biomecânicas decorrentes da modificação da técnica de avanço da tuberosidade tibial (TTA, originalmente descrita para estabilização da ruptura do ligamento cruzado cranial. Foram avaliados 10 cães, sem raça definida e com peso entre 25 e 30kg, submetidos à eutanásia por razões independentes do presente estudo. Os membros pélvicos foram distribuídos em dois grupos: G1 operado (n=10 e G2 controle (n=10, representado pelo membro contralateral. Os membros operados foram submetidos à avaliação ortopédica, goniométrica e radiográfica nos momentos 1 (articulação intacta, 2 (após desmotomia do cruzado cranial, 3 (após estabilização articular pela TTA modificada e 4 (após a desmotomia do cruzado caudal. A tuberosidade tibial foi estabilizada por um parafuso cortical em posicionamento craniocaudal e um espaçador de titânio inserido no local de osteotomia. A posição do tendão patelar perpendicular em relação ao platô tibial promoveu a neutralização da força de cisalhamento tibial cranial, apesar da permanência do movimento de gaveta cranial em todos os joelhos. Os testes biomecânicos confirmam a viabilidade do método empregado para estabilização da tuberosidade tibial e sustentam a realização de estudos clínicos futuros para validação da técnica.

  15. Use of thermal analysis techniques (TG-DSC) for the characterization of diverse organic municipal waste streams to predict biological stability prior to land application.

    Science.gov (United States)

    Fernández, José M; Plaza, César; Polo, Alfredo; Plante, Alain F

    2012-01-01

    The use of organic municipal wastes as soil amendments is an increasing practice that can divert significant amounts of waste from landfill, and provides a potential source of nutrients and organic matter to ameliorate degraded soils. Due to the high heterogeneity of organic municipal waste streams, it is difficult to rapidly and cost-effectively establish their suitability as soil amendments using a single method. Thermal analysis has been proposed as an evolving technique to assess the stability and composition of the organic matter present in these wastes. In this study, three different organic municipal waste streams (i.e., a municipal waste compost (MC), a composted sewage sludge (CS) and a thermally dried sewage sludge (TS)) were characterized using conventional and thermal methods. The conventional methods used to test organic matter stability included laboratory incubation with measurement of respired C, and spectroscopic methods to characterize chemical composition. Carbon mineralization was measured during a 90-day incubation, and samples before and after incubation were analyzed by chemical (elemental analysis) and spectroscopic (infrared and nuclear magnetic resonance) methods. Results were compared with those obtained by thermogravimetry (TG) and differential scanning calorimetry (DSC) techniques. Total amounts of CO(2) respired indicated that the organic matter in the TS was the least stable, while that in the CS was the most stable. This was confirmed by changes detected with the spectroscopic methods in the composition of the organic wastes due to C mineralization. Differences were especially pronounced for TS, which showed a remarkable loss of aliphatic and proteinaceous compounds during the incubation process. TG, and especially DSC analysis, clearly reflected these differences between the three organic wastes before and after the incubation. Furthermore, the calculated energy density, which represents the energy available per unit of organic matter, showed a strong correlation with cumulative respiration. Results obtained support the hypothesis of a potential link between the thermal and biological stability of the studied organic materials, and consequently the ability of thermal analysis to characterize the maturity of municipal organic wastes and composts. PMID:21944875

  16. Modified stabilization method for the tibial tuberosity advancement technique: a biomechanical study / Modificação da técnica de avanço da tuberosidade tibial: estudo biomecânico

    Scientific Electronic Library Online (English)

    Bruno Testoni, Lins; Sheila Canevese, Rahal; Mário Jefferson, Louzada; José Carlos, Dalmas; André Luis, Selmi.

    2009-04-01

    Full Text Available O presente estudo teve como objetivo determinar as alterações biomecânicas decorrentes da modificação da técnica de avanço da tuberosidade tibial (TTA), originalmente descrita para estabilização da ruptura do ligamento cruzado cranial. Foram avaliados 10 cães, sem raça definida e com peso entre 25 e [...] 30kg, submetidos à eutanásia por razões independentes do presente estudo. Os membros pélvicos foram distribuídos em dois grupos: G1 operado (n=10) e G2 controle (n=10), representado pelo membro contralateral. Os membros operados foram submetidos à avaliação ortopédica, goniométrica e radiográfica nos momentos 1 (articulação intacta), 2 (após desmotomia do cruzado cranial), 3 (após estabilização articular pela TTA modificada) e 4 (após a desmotomia do cruzado caudal). A tuberosidade tibial foi estabilizada por um parafuso cortical em posicionamento craniocaudal e um espaçador de titânio inserido no local de osteotomia. A posição do tendão patelar perpendicular em relação ao platô tibial promoveu a neutralização da força de cisalhamento tibial cranial, apesar da permanência do movimento de gaveta cranial em todos os joelhos. Os testes biomecânicos confirmam a viabilidade do método empregado para estabilização da tuberosidade tibial e sustentam a realização de estudos clínicos futuros para validação da técnica. Abstract in english The present study aimed to determine biomechanical alterations resultant from a modification in the fixation method of the tibial tuberosity advancement technique (TTA), originally described for stabilization of the cranial cruciate-deficient stifle. Ten adult mongrel dogs weighing 25-30kg were used [...] . After euthanasia, performed for reasons unrelated to this study, the hind limbs were distributed into two groups: G1 operated (n=10) and G2 control (n=10), represented by the contralateral limb. The operated hind limbs were orthopedically, goniometrically and radiographically evaluated, sequentially at four moments: moment 1, in intact joints; moment 2, after cranial cruciate desmotomy; moment 3, after surgical stabilization of the stifle joint using modified TTA; and moment 4, after caudal cruciate ligament desmotomy. The tibial tuberosity was stabilized by one shaft screw craniocaudally and a titanium cage inserted at the osteotomy site. The position of the patellar tendon at 90° in relation to the tibial plateau allowed cranial tibial thrust force neutralization, despite cranial drawer motion maintenance in all dogs. The biomechanical tests confirm the viability of the tibial tuberosity fixation method and support future clinical trials to validate the technique.

  17. Which Microbial Communities Are Present? Using Fluorescence In Situ Hybridisation (FISH): Microscopic Techniques for Enumeration of Troublesome Microorganisms in Oil and Fuel Samples

    Science.gov (United States)

    Holmkvist, Lars; Østergaard, Jette Johanne; Skovhus, Torben Lund

    Enumeration of microbes involved in souring of oil fields and microbiologically influenced corrosion (MIC) with culture-based methods, usually yield inadequate and contradictory results. Any cultivation step will almost certainly alter the population structure of the sample and thus the results of cultivation analysis are not a good basis for mitigation decisions. The need for methods that are cultivation independent has over the past 10 years facilitated the development of several analytical methods for determination of bacterial identity, quantity, and to some extent function, applied directly to samples of the native population. In this chapter, we demonstrate the features and benefits of applying microscopic techniques to a situation often encountered in the oil and petroleum industry: Control of microbial growth in fuel storage tanks. The methods described in this chapter will focus on direct counts of specific groups of microorganisms with microscopy and these are based on the detection of genetic material and not on culturing.

  18. Use of 3D cartilage scaffolds for the stabilization of implants and bone regeneration with the fit-lock technique

    Scientific Electronic Library Online (English)

    Giovanni, Falisi; Massimo, Galli; Pedro, Vittorini-Velasquez; Juan C, Gallegos-Rivera; Roberto, Minasi; Alberto, De Biase; Carlo, Di Paolo.

    2013-12-01

    Full Text Available Los procedimientos quirurgicos para la aplicacion de los implantes en los sectores latero superiores, estan condicionadas por la neumatizacion del seno y la disponibilidad del hueso residual. En estos casos el injerto de hueso autologo permanece como la mejor opcion, pero a causa de la morbilidad as [...] ociada al sitio donante y a las complicaciones post quirurgicas, se pusieron a disposicion diversas alternativas de sustitutos oseos, que implican sin embargo un aumento de los costos economicos y con limitadas propiedades osteoinductivas. Tales defectos pueden ser compensados con nuevas estrategias de regeneracion biologica y mecanica de los tejidos a los cuales fue dirigida la ingenieria biologica y mecanica en los ultimos anos. Se presenta una nueva posibilidad terapeutica en la aplicacion de los implantes en el maxilar superior con disponibilidad osea inferior a los 4 mm, mediante la utilizacion de andamios 3D confeccionados en cartilago de cerdo libre de antigenos obtenido segun la tecnica Fit-Lock. Se realizo un estudio longitudinal en 18 casos consecutivos evidenciando al cabo de un ano de la carga implantologica, un exito del 95,2%. Las ventajas en esta nueva tecnica son: 1)La recuperacion funcional y anatomica del antro del maxilar 2).La aplicacion inmediata de los implantes; 3)Reduccion de los tiempos quirurgicos; 4) Ausencia de morbilidad para el paciente; 5) Uso de anestesia local; 6)Uso de implantes con diametros superiores a los 4 mm. Abstract in english The surgical procedures for implant applications on the lateralupper areas depend on sinus pneumatization and availability of the residual bone. In these cases, autologous bone grafting remains the gold standard. Nevertheless, because of the morbidity associated to the donor site and the post-surgic [...] al complications, several alternative bone substitutes have been introduced, which, however, imply additional costs and show limited osteoinductive properties. Such limitations can be compensated with new regeneration strategies for biological and mechanical tissue restoration, a subject which has been addressed by tissue engineering in recent years. The authors present a new therapeutic option for implant application in the upper maxilla with bone availability less than 4 mm by using 3D scaffolds obtained from antigen-free porcine cartilage in the fit-lock technique. A longitudinal study on 18 consecutive cases was performed, with a 95.2% success rate one year after the implant. The advantages of this new technique are: 1)Functional and anatomical recovery of the maxillary antrum, 2) Immediate application of the implants; 3) Reduction of surgical times; 4) Absence of patient morbidity; 5)Local anesthesia; 6) Use of implants with a diameter > 4 mm.

  19. Techniques of rehabilitation of polluted sites and soils. Synthesis files; Techniques de rehabilitation des sites et sols pollues. Fiches de synthese

    Energy Technology Data Exchange (ETDEWEB)

    Roudier, P. [SITA Remediation, 92 - Nanterre (France)

    2005-04-01

    The files presented in this article make a status of the different existing techniques for the rehabilitation of polluted soils and aquifers. Each file treats of both the theoretical principle of the technique and of the practical implementation of it. The choice of a given technique requires to take into consideration several parameters linked with the type of soil, with the type of pollutant, with the site constraints, with the technical-economical aspect etc. The techniques considered are: air sparging, natural attenuation, reactive barriers, bio-augmentation, bio-slurry (bioreactor), bio-stimulation, bio-hillock (bio-centre, bio-pile), bio-venting, soil composting, ex situ thermal desorption, in situ thermal desorption, electro-kinetics, electro-oxidation, excavating, incineration, ex situ soil washing, in situ washing (flushing), microwaves, in situ oxidation, UV photo-oxidation, phyto-remediation, pump and treat, pyrolysis, double phase extraction, reduction, slurping (triple-phase extraction), solidification/stabilization, surfactant/co-surfactant, solvents/co-solvents, aerobic biological treatment, anaerobic biological treatment, fungi treatment, screening, ultrasounds, venting (soil vapor extraction, vacuum extraction), vitrification. (J.S.)

  20. Illumination Sufficiency Survey Techniques: In-situ Measurements of Lighting System Performance and a User Preference Survey for Illuminance in an Off-Grid, African Setting

    Energy Technology Data Exchange (ETDEWEB)

    Alstone, Peter; Jacobson, Arne; Mills, Evan

    2010-08-26

    Efforts to promote rechargeable electric lighting as a replacement for fuel-based light sources in developing countries are typically predicated on the notion that lighting service levels can be maintained or improved while reducing the costs and environmental impacts of existing practices. However, the extremely low incomes of those who depend on fuel-based lighting create a need to balance the hypothetically possible or desirable levels of light with those that are sufficient and affordable. In a pilot study of four night vendors in Kenya, we document a field technique we developed to simultaneously measure the effectiveness of lighting service provided by a lighting system and conduct a survey of lighting service demand by end-users. We took gridded illuminance measurements across each vendor's working and selling area, with users indicating the sufficiency of light at each point. User light sources included a mix of kerosene-fueled hurricane lanterns, pressure lamps, and LED lanterns.We observed illuminance levels ranging from just above zero to 150 lux. The LED systems markedly improved the lighting service levels over those provided by kerosene-fueled hurricane lanterns. Users reported that the minimum acceptable threshold was about 2 lux. The results also indicated that the LED lamps in use by the subjects did not always provide sufficient illumination over the desired retail areas. Our sample size is much too small, however, to reach any conclusions about requirements in the broader population. Given the small number of subjects and very specific type of user, our results should be regarded as indicative rather than conclusive. We recommend replicating the method at larger scales and across a variety of user types and contexts. Policymakers should revisit the subject of recommended illuminance levels regularly as LED technology advances and the price/service balance point evolves.

  1. Accuracy assessment of water vapour measurements from in-situ and remote sensing techniques during the DEMEVAP 2011 campaign at OHP

    Science.gov (United States)

    Bock, O.; Bosser, P.; Bourcy, T.; David, L.; Goutail, F.; Hoareau, C.; Keckhut, P.; Legain, D.; Pazmino, A.; Pelon, J.; Pipis, K.; Poujol, G.; Sarkissian, A.; Thom, C.; Tournois, G.; Tzanos, D.

    2013-04-01

    The Development of Methodologies for Water Vapour Measurement (DEMEVAP) project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems. A field experiment was conducted in September-October 2011 at Observatoire de Haute Provence. Two Raman lidars, a stellar spectrometer (SOPHIE), a differential absorption spectrometer (SAOZ), a sun photometer (AERONET), 5 GPS receivers and 4 types of radiosondes (Vaisala RS92, MODEM M2K2-DC and M10, and Meteolabor Snow-White) participated in the campaign. A total of 26 balloons with multiple radiosondes were flown during 16 clear nights. This paper presents preliminary findings from the analysis of all these datasets. Several classical Raman lidar calibration methods are evaluated which use either Vaisala RS92 measurements, point capacitive humidity measurements, or GPS integrated water vapour (IWV) measurements. A novel method proposed by Bosser et al. (2010) is also tested. It consists in calibrating the lidar measurements during the GPS data processing. The methods achieve a repeatability of 4-5%. A drift in the IGN-LATMOS Raman lidar calibration of 15% over the 45 days of the experiment is evidenced but not yet explained. When this drift is removed, the precision of the calibration factors improves to 2-3%. However, the variations in the absolute calibration factor between methods and types of reference data remain at the level of 7%. The intercomparison of radiosonde measurements shows good agreement between RS92 and Snow-White measurements up to 12 km. An overall dry bias is found in the measurements from both MODEM radiosondes. Investigation of situations with low RH values (RS92 due to a saturation of the Peltier device. However, on other occasions, a dry bias is found in RS92, instead. Raman lidar water vapour measurements were useful to distinguish between which of the radiosondes was biased. On average, both RS92 and Snow-White measurements show a slight moist bias at night-time compared to GPS IWV, while the MODEM measurements show a large dry bias. The spectrometer IWV measurements contained a large bias that is currently under investigation. The sun photometer (daytime) and calibrated Raman lidar (night-time) IWV measurements showed excellent agreement with the GPS IWV measurements.

  2. Accuracy assessment of water vapour measurements from in-situ and remote sensing techniques during the DEMEVAP 2011 campaign at OHP

    Directory of Open Access Journals (Sweden)

    O. Bock

    2013-04-01

    Full Text Available The Development of Methodologies for Water Vapour Measurement (DEMEVAP project aims at assessing and improving humidity sounding techniques and establishing a reference system based on the combination of Raman lidars, ground-based sensors and GPS. Such a system may be used for climate monitoring, radiosonde bias detection and correction, satellite measurement calibration/validation, and mm-level geodetic positioning with Global Navigation Satellite Systems. A field experiment was conducted in September–October 2011 at Observatoire de Haute Provence. Two Raman lidars, a stellar spectrometer (SOPHIE, a differential absorption spectrometer (SAOZ, a sun photometer (AERONET, 5 GPS receivers and 4 types of radiosondes (Vaisala RS92, MODEM M2K2-DC and M10, and Meteolabor Snow-White participated in the campaign. A total of 26 balloons with multiple radiosondes were flown during 16 clear nights. This paper presents preliminary findings from the analysis of all these datasets. Several classical Raman lidar calibration methods are evaluated which use either Vaisala RS92 measurements, point capacitive humidity measurements, or GPS integrated water vapour (IWV measurements. A novel method proposed by Bosser et al. (2010 is also tested. It consists in calibrating the lidar measurements during the GPS data processing. The methods achieve a repeatability of 4–5%. A drift in the IGN-LATMOS Raman lidar calibration of 15% over the 45 days of the experiment is evidenced but not yet explained. When this drift is removed, the precision of the calibration factors improves to 2–3%. However, the variations in the absolute calibration factor between methods and types of reference data remain at the level of 7%. The intercomparison of radiosonde measurements shows good agreement between RS92 and Snow-White measurements up to 12 km. An overall dry bias is found in the measurements from both MODEM radiosondes. Investigation of situations with low RH values (<10% in the lower and middle troposphere reveals, on occasion, a lower RH detection limit in the Snow-White measurements compared to RS92 due to a saturation of the Peltier device. However, on other occasions, a dry bias is found in RS92, instead. Raman lidar water vapour measurements were useful to distinguish between which of the radiosondes was biased. On average, both RS92 and Snow-White measurements show a slight moist bias at night-time compared to GPS IWV, while the MODEM measurements show a large dry bias. The spectrometer IWV measurements contained a large bias that is currently under investigation. The sun photometer (daytime and calibrated Raman lidar (night-time IWV measurements showed excellent agreement with the GPS IWV measurements.

  3. The dry and damp heat stability of chalcopyrite solar cells prepared with an indium sulfide buffer deposited by the spray-ILGAR technique

    International Nuclear Information System (INIS)

    Cadmium free chalcopyrite solar cells based upon industrial Cu(In,Ga)(S,Se)2 absorber films with indium sulfide buffer layers deposited by the Spray-ILGAR technique have recently achieved certified efficiencies of 14.7%. Here we report for the first time on the stability of these cells. The cells were subjected to dry and damp heat conditions of 85 deg. C and 85% humidity for 100 h without encapsulation. The resulting cell parameters are measured and compared to cells prepared using a standard cadmium sulfide layer deposited by chemical bath deposition. Two different zinc oxide window processes were used for both buffers and the effect of changing the zinc oxide process is discussed. Before the damp heat tests, using an rf-sputtered zinc oxide process the indium sulfide buffers have an efficiency equal to the cadmium sulfide buffered cells and when using a second rf/dc-sputtered zinc oxide process a superior efficiency is obtained with the indium sulfide. The biggest loss in efficiency after damp heat testing is shown to arise from shunt paths at the scribe lines. The indium sulfide buffered cells degrade by only 11% under damp heat conditions when measured after rescribing. A difference between the cell efficiencies using two different zinc oxide windows highlights the interdependence of the process steps

  4. Estabilização de taludes marginais com técnicas de bioengenharia de solos no Baixo São Francisco / Riverbank stabilization with soil bioengineering techniques at the Lower São Francisco River

    Scientific Electronic Library Online (English)

    Francisco S. R., Holanda; Igor P. da, Rocha; Vandemberg S., Oliveira.

    2008-12-01

    Full Text Available Os taludes marginais no baixo curso do Rio São Francisco, dominados por solos de baixa coesão sofrem com o avanço da erosão que causa recuo da margem e assoreamento do canal. A proposta deste trabalho foi estudar a aplicação da bioengenharia de solos visando ao controle da erosão por meio da estabil [...] ização dos taludes marginais, para posterior recuperação da vegetação ciliar. A área experimental foi dividida em dois tratamentos com 3 repetições, sendo o tratamento sem uso de bioengenharia (testemunha) implantado à montante do fluxo da água e o tratamento com uso de bioengenharia, à jusante. A técnica de bioengenharia de solos foi caracterizada pela associação do geotêxtil Fibrax® 400 BF com gramínea Brachiaria decumbens, e retentores de sedimentos (Bermalongas®) ao longo da linha d'água. Para avaliação do comportamento do talude realizou-se levantamento topográfico planialtimétrico aos 30, 180, 360 e 540 dias de implantação do experimento. No tratamento sem proteção de bioengenharia (testemunha) ocorreram variações significativas no perfil topográfico, enquanto no talude protegido com bioengenharia ocorreram movimentos de massa pouco expressivos. Abstract in english The river banks of the Lower São Francisco River, which mostly present low cohesion soils, have suffered with the increase in erosion, leading to margin retreat and sedimentation. The purpose of this work was to study the application of a soil bioengineering technique in order to control the riverba [...] nk erosion by its stabilization aiming toward the riparian vegetation recovery. The experimental area was divided in two different assays, with three replications. The test assay (without the soil bioengineering technique) was installed upstream, and the assay with soil bioengineering was installed downsteam. The soil bioengineering technique was characterized by the association of the biotextile screen under the trade name Fibrax® 400BF, associated with Brachiaria decumbens grass and sediment retainers under the trade name Bermalonga®, installed along the river bank base. In order to evaluate the riverbank changes, direct topographic measures was used. The data was collected 30, 180, 360 and 540 days after the beginning of the study. At the assay without soil bioengineering protection, strong slope soil mass movement occurred. The opposite behavior occurred in the assay with soil bioengineering, with a very little soil movement.

  5. Application of the electrophoretic deposition technique for obtaining Yttria-stabilized zirconia tubes; Aplicacao da tecnica de deposicao eletroforetica para a obtencao de tubos ceramicos de zirconia-itria

    Energy Technology Data Exchange (ETDEWEB)

    Caproni, E.; Muccillo, R., E-mail: ecaproni@gmail.com, E-mail: muccillo@usp.br [Centro de Ciencia e Tecnologia de Materiais, Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2012-01-15

    The electrophoretic deposition (EPD) is recognized as the most versatile technique for processing particulate materials, due to low cost, deposition in minutes and forming of pieces with complex geometry shapes. In this work an experimental setup for the simultaneous conformation of 16 ceramic tubes by EPD was built. Bimodal submicron Yttria-stabilized zirconia particles were deposited into graphite electrodes, after suitably adjusting the rheological characteristics of the suspension in isopropanol. After graphite burning and YSZ sintering at 1500 deg C, the ceramic tubes were characterized by X-ray diffraction, scanning probe microscope, impedance spectroscopy and electrical response as a function of oxygen content. Small dense one end-closed ceramic tubes, fully stabilized in the cubic phase, were successfully obtained by the EPD technique, showing the ability of that technique for processing large quantities of tubular solid electrolytes with electrical response to different amounts of oxygen according to the Nernst law (author)

  6. Geomechanical Modeling of In-situ Stresses Around a Borehole

    Science.gov (United States)

    Grandi, Samantha

    A paper presenting a modeling of the in-situ stress state associated with the severe hole enlargement of a wellbore and the geomechanical information needed to ensure wellbore stability. Geomechanical information is relevant to assure wellbore stability, i.e., to prevent damages in the formation and later on, the casing.

  7. Operational Review of the First Wireline In Situ Stress Test in Scientific Ocean Drilling

    Directory of Open Access Journals (Sweden)

    Casey Moore

    2012-04-01

    Full Text Available Scientific ocean drilling’s first in situ stress measurement was made at Site C0009A during Integrated Ocean Drilling Program (IODP Expedition 319 as part of Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE Stage 2. The Modular Formation Dynamics Tester (MDT, Schlumbergerwireline logging tool was deployed in riser Hole C0009A to measure in situ formation pore pressure, formation permeability (often reported as mobility=permeability/viscosity, and the least principal stress (S3 at several isolated depths (Saffer et al., 2009; Expedition 319 Scientists, 2010. The importance of in situ stress measurements is not only for scientific interests in active tectonic drilling, but also for geomechanical and well bore stability analyses. Certain in situ tools were not previously available for scientific ocean drilling due to the borehole diameter and open hole limits of riserless drilling. The riser-capable drillship, D/V Chikyu,now in service for IODP expeditions, allows all of the techniques available to estimate the magnitudes and orientations of 3-D stresses to be used. These techniques include downhole density logging for vertical stress, breakout and caliper log analyses for maximum horizontal stress, core-based anelastic strain recovery (ASR, used in the NanTroSEIZE expeditions in 2007–2008, and leak-off test (Lin et al., 2008 and minifrac/hydraulic fracturing (NanTroSEIZE Expedition319 in 2009. In this report, the whole operational planning process related to in situ measurements is reviewed, and lessons learned from Expedition 319 are summarized for efficient planning and testing in the future.

  8. In Situ Imaging of Atomic Quantum Gases

    Science.gov (United States)

    Hung, Chen-Lung; Chin, Cheng

    2015-09-01

    One exciting progress in recent cold atom experiments is the development of high resolution, in situ imaging techniques for atomic quantum gases.1-3 These new powerful tools provide detailed information on the distribution of atoms in a trap with resolution approaching the level of single atom and even single lattice site, and complement the welldeveloped time-of-flight method that probes the system in momentum space. In a condensed matter analogy, this technique is equivalent to locating electrons of a material in a snap shot. In situ imaging has offered a new powerful tool to study atomic gases and inspired many new research directions and ideas. In this chapter, we will describe the experimental setup of in situ absorption imaging, observables that can be extracted from the images, and new physics that can be explored with this technique.

  9. In situ activated nanostructured platform for oxidized glutathione biosensing

    International Nuclear Information System (INIS)

    Highlights: ? New nanostructured platform for GSSG determination based on multi walled carbon nanotubes and chitosan. ? The redox mediator activated in situ showed a high electrocatalytic constant for NADH electrooxidation. ? An amperometric method for GSSG determination based on NADH consumption has been presented for the first time. -- Abstract: This work describes the construction of a biosensor for glutathione disulfide (GSSG) based on a nanostructured platform composed by MWCNTs, chitosan (CHIT) and the redox mediator 3,5-dinitrobenzoic acid. The dispersion of MWCNTs and CHIT showed a good stability and was used to modify the glassy carbon electrode (GCE). The nanostructured platform was characterized by scanning electron microscopy (SEM) and electrochemical techniques. The R-NO/R-NHOH redox couple was electrogenerated in situ by cycling the potential between 0.2 and ?0.4 V vs. SCE. After activating the nanostructured platform, glutathione reductase was easily immobilized on the electrode surface by using glutaraldehyde as functional linker. The biosensor performance was optimized in terms of amount of enzyme, effect of CHIT concentration and NADH amount. Under optimized conditions, the biosensor response for GSSG sensing was linear from 2.0 up to 35 ?mol L?1 with detection and quantification limits achieving values of 0.6 and 2.0 ?mol L?1, respectively and sensitivity of 6.24 mA L mol?1. The apparent Michaelis–Menten constant (KMapp) obtained by amperometry for the immobilized glutathione reductase on the nanostructured platform was 60 ?mol L?1

  10. In situ vitrification large-scale operational acceptance test analysis

    International Nuclear Information System (INIS)

    A thermal treatment process is currently under study to provide possible enhancement of in-place stabilization of transuranic and chemically contaminated soil sites. The process is known as in situ vitrification (ISV). In situ vitrification is a remedial action process that destroys solid and liquid organic contaminants and incorporates radionuclides into a glass-like material that renders contaminants substantially less mobile and less likely to impact the environment. A large-scale operational acceptance test (LSOAT) was recently completed in which more than 180 t of vitrified soil were produced in each of three adjacent settings. The LSOAT demonstrated that the process conforms to the functional design criteria necessary for the large-scale radioactive test (LSRT) to be conducted following verification of the performance capabilities of the process. The energy requirements and vitrified block size, shape, and mass are sufficiently equivalent to those predicted by the ISV mathematical model to confirm its usefulness as a predictive tool. The LSOAT demonstrated an electrode replacement technique, which can be used if an electrode fails, and techniques have been identified to minimize air oxidation, thereby extending electrode life. A statistical analysis was employed during the LSOAT to identify graphite collars and an insulative surface as successful cold cap subsidence techniques. The LSOAT also showed that even under worst-case conditions, the off-gas system exceeds the flow requirements necessary to maintain a negative pressure on the hood covering the area being vitrified. The retention of simulated radionuclides and chemicals in the soil and off-gas system exceeds requirements so that projected emissions are one to two orders of magnitude below the maximum permissible concentrations of contaminants at the stack

  11. In situ measurement of diffusivity

    International Nuclear Information System (INIS)

    The mechanism of molecular diffusion controls the migration of contaminants in very low-permeability porous media, like underground facilities for the storage of hazardous waste. Determining of relevant diffusion coefficients is therefore of prime importance. A few techniques exist for in situ measurement of the quantity, but they suffer from many handicaps (duration, complexity and cost of the experiments). We propose here two innovative methods that have some potential to improve the situation. So far, we have found them feasible on the basis of design calculations and laboratory experiments. This work is presently protected by a patent. (author)

  12. An overview of in situ waste treatment technologies

    International Nuclear Information System (INIS)

    In situ technologies are becoming an attractive remedial alternative for eliminating environmental problems. In situ treatments typically reduce risks and costs associated with retrieving, packaging, and storing or disposing-waste and are generally preferred over ex situ treatments. Each in situ technology has specific applications, and, in order to provide the most economical and practical solution to a waste problem, these applications must be understood. This paper presents an overview of thirty different in situ remedial technologies for buried wastes or contaminated soil areas. The objective of this paper is to familiarize those involved in waste remediation activities with available and emerging in situ technologies so that they may consider these options in the remediation of hazardous and/or radioactive waste sites. Several types of in situ technologies are discussed, including biological treatments, containment technologies, physical/chemical treatments, solidification/stabilization technologies, and thermal treatments. Each category of in situ technology is briefly examined in this paper. Specific treatments belonging to these categories are also reviewed. Much of the information on in situ treatment technologies in this paper was obtained directly from vendors and universities and this information has not been verified

  13. Study On The Synthesis Of Colloidal Gold Nanoparticles By ?- Irradiation Technique Using Poly(N-Vinylpyrrolidone) (PVP) And Alginate As Stabilizer

    International Nuclear Information System (INIS)

    Gold nanoparticles were prepared from (Au3+) aqueous solution by the method of ?-ray irradiation using polyvinylpyrrolidone (PVP) and alginate as stabilizer. The absorbance peaks are obtained at wavelength of ?max = 524 nm and 527 nm for PVP and alginate respectively, due to surface plasmon resonance. The saturated conversion dose (Au3+ ? Auo) determined by UV-Vis spectroscopy is about 5 kGy. The average diameter of gold nanoparticles observed by transmission electron microscope (TEM) was of 15.9 ± 4.3 nm and 25.9 ± 8.9 nm for PVP and alginate respectively. The effect of the primary concentration of Au3+, stabilizer concentration, absorbed dose, dose rate on the particles size and stability of colloidal gold nanoparticles with storage time were also studied. (author)

  14. Acid Pit Stabilization Project (Volume 1 - Cold Testing) and (Volume 2 - Hot Testing)

    International Nuclear Information System (INIS)

    During the summer and fall of Fiscal Year 1997, a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Treatability Study was performed at the Idaho National Engineering and Environmental Laboratory. The study involved subsurface stabilization of a mixed waste contaminated soil site called the Acid Pit. This study represents the culmination of a successful technology development effort that spanned Fiscal Years 1994-1996. Research and development of the in situ grout stabilization technique was conducted. Hardware and implementation techniques are currently documented in a patent pending with the United States Patent and Trademark Office. The stabilization technique involved using jet grouting of an innovative grouting material to form a monolith out of the contamination zone. The monolith simultaneously provides a barrier to further contaminant migration and closes voids in the soil structure against further subsidence. This is accomplished by chemical incorporation of contaminants into less soluble species and achieving a general reduction in hydraulic conductivity within the monolith. The grout used for this study was TECT-HG, a relatively dense iron oxide-based cementitious grout. The treatability study involved cold testing followed by in situ stabilization of the Acid Pit. Volume 1 of this report discusses cold testing, performed as part of a ''Management Readiness Assessment'' in preparation for going hot. Volume 2 discusses the results of the hot Acid Pit Stabilization phase of this project. Drilling equipment was specifically rigged to reduce the spread of contamination, and all grouting was performed under a concrete block containing void space to absorb any grout returns. Data evaluation included examination of implementability of the grouting process and an evaluation of the contaminant spread during grouting. Following curing of the stabilized pit, cores were obtained and evaluated for toxicity characteristic leach ing procedure protocol for the main contaminant of concern, which was mercury. In addition, the cores were evaluated for the extent of mixing of the injected grout and the contaminated soil. A postgrouting geophysical evaluation of the grouted pit is presented

  15. Preparation of nanocomposites based on poly(Butylene Succinate) and montmorillonite organoclay via in situ polymerization

    International Nuclear Information System (INIS)

    Nanocomposites based on poly(butylene succinate) (PBS) and organophilic montmorillonite were synthesized via in situ polymerization using three different clay compositions (4, 6 and 8 wt%). The products were characterized by several different techniques. X-ray diffraction was useful to confirm the increase of the interlayer spacing of the clay due to the presence of the polymer chains among layers. Thermal analysis indicated that the polymerization method chosen led to materials with lower thermal stability compared to the pure PBS, due to the difficulty of chain growth in the presence of the clay. Low-field NMR technique was used to assess clay dispersion in the polymer, with exfoliated structures predominating in the nanocomposites. (author)

  16. In situ X-ray and neutron diffraction of the Ruddlesden-Popper compounds (RE2-xSrx)0.98(Fe0.8Co0.2)1-yMgyO4-? (RE=La, Pr): Structure and CO2 stability

    DEFF Research Database (Denmark)

    Chatzichristodoulou, Christodoulos; Hauback, B.C.

    2013-01-01

    The crystal structure of the Ruddlesden-Popper compounds (La 1.0Sr1.0)0.98Fe0.8Co 0.2O4-? and (La1.2Sr0.8) 0.98(Fe0.8Co0.2)0.8Mg 0.2O4-? was investigated at 1000 °C in N 2 (aO2=1×10-4) by in-situ powder neutron diffraction. In-situ powder X-ray diffraction (PXD) was also employed to investigate the temperature dependence of the lattice parameters of the compounds in air and the oxygen activity dependence of the lattice parameters at 800 °C and 1000 °C. The thermal and chemical expansion coefficients, determined along the two crystallographic directions of the tetragonal unit cell, are highly anisotropic. The equivalent pseudo-cubic thermal and chemical expansion coefficients are in agreement with values determined by dilatometry. The chemical stability in CO2 containing environments of various Ruddlesden-Popper compounds with chemical formula (RE2-xSr x)0.98(Fe0.8Co0.2) 1-yMgyO4-? (RE=La, Pr), as well as their stability limit in H2/H2O=4.5 were also determined by in-situ PXD for x=0.9, 1.0 and y=0, 0.2. © 2013 Elsevier Inc. All rights reserved.

  17. The effects of CeO{sub 2} on the activity and stability of Pt supported catalysts for methane reforming, as addressed by in situ temperature resolved XAFS and TEM analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Adriana de Paula; Araujo, Jesuina Cassia Santiago; Liberatori, Janete Werle de Camargo; Bueno, Jose Maria Correa [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil); Zanchet, Daniela [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Sousa-Aguiar, Eduardo Falabella [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES); Noronha, Fabio Bellot [Instituto Nacional de Tecnologia (INT), Rio de Janeiro, RJ (Brazil). Lab. de Catalise

    2009-07-01

    The effects of Ce as a promoter on the activity and stability of Pt/Al{sub 2}O{sub 3} and Pt/CeO{sub 2}-Al{sub 2}O{sub 3} catalysts for auto thermal reforming and partial oxidation of methane were investigated. The Pt/Ceo{sub 2}-Al{sub 2}O{sub 3} catalyst exhibited higher activity and stability than the Pt/Al{sub 2}O{sub 3} catalyst that showed strong Pt agglomeration with time on stream. The higher stability of the Pt/CeO{sub 2}-Al{sub 2}O{sub 3} catalyst was attributed to a combination of different properties: (1) hindrance of carbon deposition on the Pt surface; (2) interaction of Pt-O-Ce species in the presence of oxygen, inhibiting vapour and diffusion transport of PtO{sub 2} and mainly (3) thermal stability of the support, which prevents the loss of surface area, and consequently the sintering of the Pt. X-ray absorption fine structure spectroscopy and transmission electron microscopy were used to support these conclusions. (author)

  18. The effects of CeO2 on the activity and stability of Pt supported catalysts for methane reforming, as addressed by in situ temperature resolved XAFS and TEM analysis

    International Nuclear Information System (INIS)

    The effects of Ce as a promoter on the activity and stability of Pt/Al2O3 and Pt/CeO2-Al2O3 catalysts for auto thermal reforming and partial oxidation of methane were investigated. The Pt/Ceo2-Al2O3 catalyst exhibited higher activity and stability than the Pt/Al2O3 catalyst that showed strong Pt agglomeration with time on stream. The higher stability of the Pt/CeO2-Al2O3 catalyst was attributed to a combination of different properties: (1) hindrance of carbon deposition on the Pt surface; (2) interaction of Pt-O-Ce species in the presence of oxygen, inhibiting vapour and diffusion transport of PtO2 and mainly (3) thermal stability of the support, which prevents the loss of surface area, and consequently the sintering of the Pt. X-ray absorption fine structure spectroscopy and transmission electron microscopy were used to support these conclusions. (author)

  19. A case history comparing in situ bioventing versus ex situ bioventing of volatile fuel hydrocarbon contaminated soil

    International Nuclear Information System (INIS)

    Generally, the more efficient a bioremediation technology is at controlling oxygenation, mass transfer of the contaminant, etc., the higher the biodegradation or treatment rate of the system. Thus, ex situ bioremediation is expected to produce higher degradation rates compared to in situ bioremediation techniques due to a higher level of control over process parameters. However, a comparison between ex situ and in situ bioventing treatment rates of volatile fuel hydrocarbons in this case study indicates that the treatment rate of the ex situ bioventing system can be slower than the in situ bioventing system. Originally, ex situ bioventing of volatile fuel hydrocarbon contaminated soil was planned to remediate soils thought to be contaminated by a leaking underground gasoline storage tanks to 20 feet below ground surface. Once the impact of the contamination seemed to be deeper than the limits of the excavation equipment, in situ bioventing was initiated for the soils that remained in the subsurface. Presented within this paper is a case history of the project. The case history includes soil shredding to add nutrients prior to construction of the ex situ bioventing system, the impact of an oil field methane formation during the design and construction of the in situ bioventing system, the effects of gaseous ammonia injection into the subsurface, and operating conditions and treatment rates for both systems

  20. Quantifying the influences of atmospheric stability on air pollution in Lanzhou, China, using a radon-based stability monitor

    Science.gov (United States)

    Chambers, Scott D.; Wang, Fenjuan; Williams, Alastair G.; Xiaodong, Deng; Zhang, Hua; Lonati, Giovanni; Crawford, Jagoda; Griffiths, Alan D.; Ianniello, Antonietta; Allegrini, Ivo

    2015-04-01

    Commercially-available "stability monitors" based on in situ atmospheric radon progeny measurements remain underutilised as a tool for urban pollution studies, due in part to difficulties experienced in relating their standard output directly to the atmospheric mixing state in a consistent manner. The main confounding factor has been a lack of attention to the fact that the observed near-surface atmospheric radon concentration includes large synoptic and fetch-related components in addition to the local stability influence. Here, a technique recently developed for stability classification using a research-quality dual-flow-loop two-filter radon detector is adapted for use with a commercially-available radon-based stability monitor. Performance of the classification scheme is then tested in Lanzhou, China, a topographically-complex region renowned for low mean annual wind speeds (0.8 m s-1) and winter stagnation episodes. Based on an 11-mon