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Sample records for week in-situ enhancement

  1. Chemically enhanced in situ recovery

    Energy Technology Data Exchange (ETDEWEB)

    Sale, T. [CH2M Hill, Denver, CO (United States); Pitts, M.; Wyatt, K. [Surtek, Inc., Golden, CO (United States)] [and others

    1996-08-01

    Chemically enhanced recovery is a promising alternative to current technologies for management of subsurface releases of organic liquids. Through the inclusion of surfactants, solvents, polymers, and/or alkaline agents to a waterflood, the transport of targeted organic compounds can be increased and rates of recovery enhanced. By far, the vast majority of work done in the field of chemically enhanced recovery has been at a laboratory scale. The following text focuses on chemically enhanced recovery from a field application perspective with emphasis given to chlorinated solvents in a low permeability setting. While chlorinated solvents are emphasized, issues discussed are also relevant to organic liquids less dense than water such as petroleum products. Topics reviewed include: (1) Description of technology; (2) General technology considerations; (3) Low permeability media considerations; (4) Cost and reliability considerations; (5) Commercial availability; and (6) Case histories. Through this paper an appreciation is developed of both the potential and limitations of chemically enhanced recovery. Excluded from the scope of this paper is the in situ destruction of organic compounds through processes such as chemical or biological oxidation, chemically enhanced recovery of inorganic compounds, and ex situ soil treatment processes. 11 refs., 2 figs., 1 tab.

  2. Enhanced in situ aerobic bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Sharfe, K. [CleanEARTH Solutions Ltd., Concord, ON (Canada)

    2007-07-01

    An enhanced in situ aerobic bioremediation process was described. The process used microbe supporting emulsifications to enhance bioavailability as well as to attenuate microbe competition and boost microbial production. Microbes were added prior to application and rapidly initiated bioremediation once applied to impacted areas. The microbe supporting emulsifiers were metabolically active. The study showed that exposed surface areas increased as hydrocarbon masses were divided, which in turn increased the water/substrate interface where microbial action occurred. Nutrients were used to ensure that crowding and waste accumulation were attenuated in order to ensure that the speed of growth and reproduction progressed exponentially. Water-carrying bacteria, enzymes and nutrients were adsorbed to the soil's particle surface and then diffused between particles. The sequestered hydrocarbons were then emulsified and removed in order to be bioremediated. It was concluded that biological catalysts were used to increase microbial activity and to trigger anabolic responses in microbes. Details of a biocatalyst laboratory solution analysis were also included. tabs., figs.

  3. Enhancing in situ bioremediation with pneumatic fracturing

    International Nuclear Information System (INIS)

    A major technical obstacle affecting the application of in situ bioremediation is the effective distribution of nutrients to the subsurface media. Pneumatic fracturing can increase the permeability of subsurface formations through the injection of high pressure air to create horizontal fracture planes, thus enhancing macro-scale mass-transfer processes. Pneumatic fracturing technology was demonstrated at two field sites at Tinker Air Force Base, Oklahoma City, Oklahoma. Tests were performed to increase the permeability for more effective bioventing, and evaluated the potential to increase permeability and recovery of free product in low permeability soils consisting of fine grain silts, clays, and sedimentary rock. Pneumatic fracturing significantly improved formation permeability by enhancing secondary permeability and by promoting removal of excess soil moisture from the unsaturated zone. Postfracture airflows were 500% to 1,700% higher than prefracture airflows for specific fractured intervals in the formation. This corresponds to an average prefracturing permeability of 0.017 Darcy, increasing to an average of 0.32 Darcy after fracturing. Pneumatic fracturing also increased free-product recovery rates of number 2 fuel from an average of 587 L (155 gal) per month before fracturing to 1,647 L (435 gal) per month after fracturing

  4. In situ upgrading : coupled enhanced oil recovery with in situ upgrading : ultra dispersed catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Almao, P.P. [Calgary Univ., AB (Canada). Schulich School of Engineering]|[Alberta Ingenuity Centre for In Situ Energy, Edmonton, AB (Canada)

    2007-07-01

    This paper presented a research program that demonstrates the use of ultra dispersed (UD) catalysts as a means of improving the economics of oil sands processing. An outline of current processing techniques was provided. In situ upgrading options included the use of solvents, thermal methods, radiation methods, bio-upgrading, and thermo-catalytic methods. Enhanced oil recovery (EOR) is often combined with in situ upgrading to increase the efficiency of energy use in reservoirs where thermal methods are used. The use of diluents often reduces water usage as well as problems related to contamination and emissions. Recent studies have suggested that vis-breaking (VB) is the lowest investment residual conversion process currently available for in situ processing. UD catalyst formulations can be commercially prepared using nano-particle techniques, and can be used in portable configurations. UD catalysts are known to outperform conventional fixed bed types for both hydrogenation, hydrotreating, and hydrocracking. Research is currently being conducted at the Alberta Ingenuity Centre for In Situ Energy to examine issues related to particles recycling, deactivation and losses. Permeability studies are also being conducted to examine permeability rates of emulsions and nanoparticles through oil sands porous media. The short term financial rewards of various in situ upgrading technologies were also considered. refs., tabs, figs.

  5. In situ hydrogenation of molybdenum oxide nanowires for enhanced supercapacitors

    KAUST Repository

    Shakir, Imran

    2014-01-01

    In situ hydrogenation of orthorhombic molybdenum trioxide (?-MoO 3) nanowires has been achieved on a large scale by introducing alcohol during the hydrothermal synthesis for electrochemical energy storage supercapacitor devices. The hydrogenated molybdenum trioxide (H xMoO3) nanowires yield a specific capacitance of 168 F g-1 at 0.5 A g-1 and maintain 108 F g-1 at 10 A g-1, which is 36-fold higher than the capacitance obtained from pristine MoO3 nanowires at the same conditions. The electrochemical devices made with HxMoO3 nanowires exhibit excellent cycling stability by retaining 97% of their capacitance after 3000 cycles due to an enhanced electronic conductivity and increased density of hydroxyl groups on the surface of the MoO3 nanowires. This journal is © The Royal Society of Chemistry.

  6. Depth enhancement techniques for the in situ vitrification process

    International Nuclear Information System (INIS)

    In-situ vitrification (ISV) is a process by which electrical energy is supplied to a soil/waste matrix. The resulting Joule heat raises the temperature of the soil/waste matrix, producing a pool of molten soil. Since its inception, there have been many successful applications of the technology to both staged and actual waste sites. However, there has been some difficulty in extending the attainable treatment melt depth to levels greater than 5 m. Results obtained from application of two novel approaches for extending the ultimate treatment depth attainable with in-situ vitrification (ISV) are presented. In the first, the electrode design is modified to concentrate the Joule heat energy delivered to the soil/waste matrix in the lower region of the target melt zone. This electrode design has been dubbed the hot-tip electrode. Results obtained from both computational and experimental investigations of this design concept indicate that some benefit toward ISV depth enhancement was realized with these hot-tip electrodes. A second, alternative approach to extending process depth with ISV involves initiating the melt at depth and propagating it in either vertical direction (e.g., downward, upward, or both) to treat the target waste zone. A series of engineering-scale experiments have been conducted to assess the benefits of this approach. The results from these tests indicate that ISV may be effectively initiated and sustained using this subsurface start-up technique. A survey of these experiments and the associated results are presented herein, together with brief discussion of some considerations regarding setup and implementation of this subsurface start-up technique

  7. In situ enhanced soil mixing. Innovative technology summary report

    International Nuclear Information System (INIS)

    In Situ Enhanced Soil Mixing (ISESM) is a treatment technology that has been demonstrated and deployed to remediate soils contaminated with volatile organic compounds (VOCs). The technology has been developed by industry and has been demonstrated with the assistance of the U.S. Department of Energy's Office of Science and Technology and the Office of Environmental Restoration. The technology is particularly suited to shallow applications, above the water table, but can be used at greater depths. ISESM technologies demonstrated for this project include: (1) Soil mixing with vapor extraction combined with ambient air injection. [Contaminated soil is mixed with ambient air to vaporize volatile organic compounds (VOCs). The mixing auger is moved up and down to assist in removal of contaminated vapors. The vapors are collected in a shroud covering the treatment area and run through a treatment unit containing a carbon filter or a catalytic oxidation unit with a wet scrubber system and a high efficiency particulate air (HEPA) filter.] (2) soil mixing with vapor extraction combined with hot air injection [This process is the same as the ambient air injection except that hot air or steam is injected.] (3) soil mixing with hydrogen peroxide injection [Contaminated soil is mixed with ambient air that contains a mist of diluted hydrogen peroxide (H2O2) solution. The H2O2 solution chemically oxidizes the VOCs to carbon dioxide (CO2) and water.] (4) soil mixing with grout injection for solidification/stabilization [Contaminated soil is mixed as a cement grout is injected under pressure to solidify and immobilize the contaminated soil in a concrete-like form.] The soils are mixed with a single-blade auger or with a combination of augers ranging in diameter from 3 to 12 feet

  8. IN SITU STEAM ENHANCED RECOVERY PROCESS - HUGHES ENVIRONMENTAL SYSTEMS, INC. - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    Science.gov (United States)

    This Innovative Technology Evaluation report summarizes the findings of an evaluation of the in situ Steam Enhanced Recovery Process (SERP) operated by Hughes Environmental Systems, Inc. at the Rainbow Disposal facility in Huntington Beach, California. he technology demonstration...

  9. Enhanced biodegradation of hydrocarbons in situ by soil venting

    International Nuclear Information System (INIS)

    Soil venting has been used for many years as a cost-effective method for in-situ treatment of volatile hydrocarbons such as gasoline. The process of soil venting involves flushing contaminated soils with air to remove volatile hydrocarbons. The rate of treatment depends on the rate that the hydrocarbon contaminants partition into the mobile air phase and the volume of air that can be effectively moved through the soils. More recently, the amount of microbial hydrocarbon removal that occurs during conventional soil venting has been extensively studied (Miller 1991, Dupont 1991). Often, over one-half of the hydrocarbon removal achieved by soil venting is due to natural biodegradation stimulated by the venting process. With proper design and operation, biological removal can account for 85 percent or more of the total hydrocarbons (Miller 1991). State and local regulations often require permitting, monitoring, and treatment of soil venting off gases that discharge to the atmosphere. The cost of these control measures typically constitutes at least 50% of the soil venting remediation costs (Miller 1991). By modification of the soil venting process, hydrocarbon contaminants can be biologically removed in situ to reduce or eliminate air emissions. The 'bioventing' process can also biodegrade less-volatile hydrocarbons and allows treatment of less permeable soils since reduced air flows can be used for treatment

  10. Cost studies of thermally enhanced in situ soil remediation technologies

    International Nuclear Information System (INIS)

    This report describes five thermally enhanced technologies that may be used to remediate contaminated soil and water resources. The standard methods of treating these contaminated areas are Soil Vapor Extraction (SVE), Excavate ampersand Treat (E ampersand T), and Pump ampersand Treat (P ampersand T). Depending on the conditions at a given site, one or more of these conventional alternatives may be employed; however, several new thermally enhanced technologies for soil decontamination are emerging. These technologies are still in demonstration programs which generally are showing great success at achieving the expected remediation results. The cost savings reported in this work assume that the technologies will ultimately perform as anticipated by their developers in a normal environmental restoration work environment. The five technologies analyzed in this report are Low Frequency Heating (LF or Ohmic, both 3 and 6 phase AC), Dynamic Underground Stripping (DUS), Radio Frequency Heating (RF), Radio Frequency Heating using Dipole Antennae (RFD), and Thermally Enhanced Vapor Extraction System (TEVES). In all of these technologies the introduction of heat to the formation raises vapor pressures accelerating contaminant evaporation rates and increases soil permeability raising diffusion rates of contaminants. The physical process enhancements resulting from temperature elevations permit a greater percentage of volatile organic compound (VOC) or semi- volatile organic compound (SVOC) contaminants to be driven out of the soils for treatment or capture in a much shorter time period. This report presents the results of cost-comparative studies between these new thermally enhanced technologies and the conventional technologies, as applied to five specific scenarios

  11. An integrated numerical and physical modeling system for an enhanced in situ bioremediation process

    International Nuclear Information System (INIS)

    Groundwater contamination due to releases of petroleum products is a major environmental concern in many urban districts and industrial zones. Over the past years, a few studies were undertaken to address in situ bioremediation processes coupled with contaminant transport in two- or three-dimensional domains. However, they were concentrated on natural attenuation processes for petroleum contaminants or enhanced in situ bioremediation processes in laboratory columns. In this study, an integrated numerical and physical modeling system is developed for simulating an enhanced in situ biodegradation (EISB) process coupled with three-dimensional multiphase multicomponent flow and transport simulation in a multi-dimensional pilot-scale physical model. The designed pilot-scale physical model is effective in tackling natural attenuation and EISB processes for site remediation. The simulation results demonstrate that the developed system is effective in modeling the EISB process, and can thus be used for investigating the effects of various uncertainties. - An integrated modeling system was developed to enhance in situ bioremediation processes

  12. In situ microbial systems for the enhancement of oil recovery

    International Nuclear Information System (INIS)

    Microbial Enhancement of Oil Recovery (MEOR) offers important new opportunities in the quest for increased oil production. It refers not to a single technique but rather to a collection of methodologies, analogous to parallel non-microbiological methods. MEOR has relevance for many type of production and reservoir problems detailed protocols: may be tailored specifically to a range of individual reservoir conditions. Microorganisms downhole can generate a wide variety of chemical products from inexpensive feed stocks: where these are more cost-effective than oil field chemicals injected from the surface, microbial methods may win widespread acceptance. MEOR methods must be defined precisely; in any particular reservoir procedure their proposed mechanism of action must be clearly understood and criteria established for evaluating their success. The most important applications for MEOR are 1) the production f insoluble or highly viscous polymer to control coning or to plug selectively high permeability thief zones and fractures, 2) the continuous generation of the active agents for polymer-and/or surfactant floods, 3) matrix acidisation and acid fracturing in carbonate rocks stimulate flows into production wells. All these approaches are currently actively been explored; several programmes for field-testing microbial EOR methods already exist, or are being readied, and rapid progress is likely within the next few years. (author)

  13. Application Research of Enhanced in-situ micro-ecological Remediation for Oil Contaminated Soil

    Directory of Open Access Journals (Sweden)

    Sheng Zhang

    2013-12-01

    Full Text Available The reduction of the oil content in soil contaminated by the exploitation of oil field in Zhongyuan District that was then recovered for use has been realized in this paper, through the enhanced in-situ micro-ecological remediation method that is micro-ecological remediation technique, by which the cultivation of alfalfa is combined with the regulation of soil environmental factors by means of the enhanced in-situ microbial communities companied with physical and chemical means. The experimental results showed that the oil contents in the contaminated soil with the average 2898.25 mg/kg can be reduced to about 99.37% after the in-situ micro-ecological remediation after the above mentioned recovery for 99 days, which demonstrated the effectiveness of the in-situ micro-ecological remediation methods for oil contaminated soil in this district, meanwhile, the practical and feasible application of these methods have been explored in this paper.

  14. Enhancement of biosensing performance in a droplet-based bioreactor by in situ microstreaming.

    Science.gov (United States)

    Ducloux, Olivier; Galopin, Elisabeth; Zoueshtiagh, Farzam; Merlen, Alain; Thomy, Vincent

    2010-01-01

    A droplet-based micro-total-analysis system involving biosensor performance enhancement by integrated surface-acoustic-wave (SAW) microstreaming is shown. The bioreactor consists of an encapsulated droplet with a biosensor on its periphery, with in situ streaming induced by SAW. This paper highlights the characterization by particle image tracking of the speed distribution inside the droplet. The analyte-biosensor interaction is then evaluated by finite element simulation with different streaming conditions. Calculation of the biosensing enhancement shows an optimum in the biosensor response. These results confirm that the evaluation of the Damköhler and Peclet numbers is of primary importance when designing biosensors enhanced by streaming. PMID:20644661

  15. Enhancement of biosensing performance in a droplet-based bioreactor by in situ microstreaming

    OpenAIRE

    Ducloux, Olivier; Galopin, Elisabeth; Zoueshtiagh, Farzam; Merlen, Alain; Thomy, Vincent

    2010-01-01

    A droplet-based micro-total-analysis system involving biosensor performance enhancement by integrated surface-acoustic-wave (SAW) microstreaming is shown. The bioreactor consists of an encapsulated droplet with a biosensor on its periphery, with in situ streaming induced by SAW. This paper highlights the characterization by particle image tracking of the speed distribution inside the droplet. The analyte-biosensor interaction is then evaluated by finite element simulation with different strea...

  16. Enhancing the design of in situ chemical barriers with multicomponent reactive transport modeling

    International Nuclear Information System (INIS)

    This paper addresses the need for systematic control of field-scale performance in the emplacement and operation of in situ chemical treatment barriers; in particular, it addresses the issue of how the local coupling of reaction kinetics and material heterogeneities at the laboratory or bench scale can be accurately upscaled to the field. The authors have recently developed modeling analysis tools that can explicitly account for all relevant chemical reactions that accompany the transport of reagents and contaminants through a chemically and physically heterogeneous subsurface rock or soil matrix. These tools are incorporated into an enhanced design methodology for in situ chemical treatment technologies, and the new methodology is demonstrated in the ongoing design of a field experiment for the In Situ Redox Manipulation (ISRM) project at the U.S. Department of Energy (DOE) Hanford Site. The ISRM design approach, which systematically integrates bench-scale and site characterization information, provides an ideal test for the new reactive transport techniques. The need for the enhanced chemistry capability is demonstrated by an example that shows how intra-aqueous redox kinetics can affect the transport of reactive solutes. Simulations are carried out on massively parallel computer architectures to resolve the influence of multiscale heterogeneities on multicomponent, multidimensional reactive transport. The technology will soon be available to design larger-scale remediation schemes

  17. IPCS: An integrated process control system for enhanced in-situ bioremediation

    International Nuclear Information System (INIS)

    To date, there has been little or no research related to process control of subsurface remediation systems. In this study, a framework to develop an integrated process control system for improving remediation efficiencies and reducing operating costs was proposed based on physical and numerical models, stepwise cluster analysis, non-linear optimization and artificial neural networks. Process control for enhanced in-situ bioremediation was accomplished through incorporating the developed forecasters and optimizers with methods of genetic algorithm and neural networks modeling. Application of the proposed approach to a bioremediation process in a pilot-scale system indicated that it was effective in dynamic optimization and real-time process control of the sophisticated bioremediation systems. - A framework of process control system was developed to improve in-situ bioremediation efficiencies and reducing operating costs

  18. Signal enhancement of surface enhanced Raman scattering and surface enhanced resonance Raman scattering using in situ colloidal synthesis in microfluidics.

    Science.gov (United States)

    Wilson, Rab; Bowden, Stephen A; Parnell, John; Cooper, Jonathan M

    2010-03-01

    We demonstrate the enhanced analytical sensitivity of both surface enhanced Raman scattering (SERS) and surface enhanced resonance Raman scattering (SERRS) responses, resulting from the in situ synthesis of silver colloid in a microfluidic flow structure, where both mixing and optical interrogation were integrated on-chip. The chip-based sensor was characterized with a model Raman active label, rhodamine-6G (R6G), and had a limit of detection (LOD) of ca. 50 fM (equivalent to single molecule detection). The device was also used for the determination of the natural pigment, scytonemin, from cyanobacteria (as an analogue for extraterrestrial life existing in extreme environments). The observed LOD of approximately 10 pM (ca. working with freshly synthesized colloid in such a flow system. In both cases, sensitivities were between 1 and 2 orders of magnitude greater in the microfluidic system than those measured using the same experimental parameters, with colloid synthesized off-chip, under quiescent conditions. PMID:20121214

  19. System for enhanced longevity of in situ microbial filter used for bioremediation

    Science.gov (United States)

    Carman, M. Leslie (San Ramon, CA); Taylor, Robert T. (Roseville, CA)

    2000-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  20. Method for enhanced longevity of in situ microbial filter used for bioremediation

    Science.gov (United States)

    Carman, M. Leslie (San Ramon, CA); Taylor, Robert T. (Roseville, CA)

    1999-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  1. Enhancement of in situ biodegradation of organic compounds in groundwater by targeted pump and treat intervention

    International Nuclear Information System (INIS)

    Highlights: • Pumping reduces contaminant toxicity below levels which stimulate in situ biodegradation. • Pumping increases the mixing of background oxidants into the plume for anaerobic respiration. • Bacterial sulphate reduction is very sensitive to contaminant concentrations. • Stable isotope analysis confirms the contribution of different biodegradation processes. • Targeted pump and treatment can enhance the natural attenuation of complex plumes. - Abstract: This study demonstrates the value of targeted pump and treatment (PAT) to enhance the in situ biodegradation of organic contaminants in groundwater for improved restoration. The approach is illustrated for a plume of phenolic compounds in a sandstone aquifer, where PAT is used for hydraulic containment and removal of dissolved phase contaminants from specific depth intervals. Time-series analysis of the plume hydrochemistry and stable isotope composition of dissolved species (?34S-SO4, ?13C-CH4, ?13C-TDIC (TDIC = Total Dissolved Inorganic Carbon)) in groundwater samples from high-resolution multilevel samplers were used to deduce changes in the relative significance of biodegradation processes and microbial activity in the plume, induced by the PAT system over 3 years. The PAT system has reduced the maximum contaminant concentrations (up to 6800 mg L?1 total phenols) in the plume by 50% to ?70% at different locations. This intervention has (i) stimulated in situ biodegradation in general, with an approximate doubling of contaminant turnover based on TDIC concentration, which has increased from <200 mg L?1 to >350 mg L?1, (ii) enhanced the activity of SO4-reducing microorganisms (marked by a declining SO4 concentration with corresponding increase in SO4-?34S to values >7–14‰V-CDT relative to background values of 1.9–6.5‰V-CDT), and (iii) where the TDIC increase is greatest, has changed TDIC-?13C from values of ?10 to ?15‰V-PDB to ??20‰V-PDB. This indicates an increase in the relative importance of respiration processes (including denitrification and anaerobic methane oxidation, AMO) that yield 13C-depleted TDIC over fermentation and acetoclastic methanogenesis that yield 13C-enriched TDIC in the plume, leading to higher contaminant turnover. The plume fringe was found to be a zone of enhanced biodegradation by SO4-reduction and methanogenesis. Isotopically heavy methane compositions (up to ?47.8‰V-PDB) and trends between ?13C-TDIC and ?13C-CH4 suggest that AMO occurs at the plume fringe where the contaminant concentrations have been reduced by the PAT system. Mass and isotope balances for inorganic carbon in the plume confirm the shift in spatial dominance of different biodegradation processes and significant increase in contribution of anaerobic respiration for contaminant biodegradation in zones targeted by the PAT system. The enhanced in situ biodegradation results from a reduction in organic contaminant concentrations in the plume to levels below those that formerly suppressed microbial activity, combined with increased supply of soluble electron acceptors (e.g. nitrate) into the plume by dispersion. An interruption of the PAT system and recovery of the dissolved organic contaminant concentrations towards former values highlights the dynamic nature of this enhancement on restoration and relatively rapid response of the aquifer microorganisms to changing conditions induced by the PAT system. In situ restoration using this combined engineered and passive approach has the potential to manage plumes of biodegradable contaminants over shorter timescales than would be possible using these methods independently. The application of PAT in this way strongly depends on the ability to ensure an adequate flux of dissolved electron acceptors into the plume by advection and dispersion, particularly in heterogeneous aquifers

  2. Integrated modelling of enhanced in situ biodenitrification in a fractured aquifer: biogeochemistry and isotope geochemistry

    Science.gov (United States)

    Rodríguez-Escales, Paula; Folch, Albert; van Breukelen, Boris M.; Vidal-Gavilan, Georgina; Soler, Albert

    2014-05-01

    Enhanced in-situ biodenitrification is a feasible technology to recovery groundwater polluted by nitrates and achieves drinking water standards. Under optimum conditions, nitrate is reduced by autochthonous bacteria trough different reactions until arrive to harmless dinitrogen gas. Isotopic fractionation monitoring in field applications allows knowing the exact degree and the real scope of this technology. Using the Rayleigh equation the change in the isotope ratio of the nitrate molecule (?15N-NO3-, ?18O-NO3-) is related to the fraction of molecules remaining as a result of biodenitrification. However, Rayleigh application at field scale is sometimes limited due to other processes involved during groundwater flow such as dispersion or adsorption and geological media heterogeneities that interferes in concentration values. Then, include isotope fractionation processes in reactive transport models is a useful tool to interpret and predict data from in-situ biodenitrification. We developed a reactive transport model of enhanced in situ application at field scale in a fractured aquifer that considers biogeochemical processes as well as isotope fractionation to enable better monitoring and management of this technology. Processes considered were: microbiological- exogenous and endogenous nitrate and sulfate respiration coupled with microbial growth and decay, geochemical reactions (precipitation of calcite) and isotopic fractionation (?15N-NO3-; ?18O- NO3- and carbon isotope network). The 2-D simulations at field scale were developed using PHAST code. Modeling of nitrate isotope geochemistry has allowed determining the extent of biodenitrification in model domain. We have quantified which is the importance in decreasing of nitrate concentrations due to biodegradation (percentage of biodegradation, 'B%') and due to dilution process (percentage of dilution, 'D%'). On the other hand, the stable carbon isotope geochemistry has been modeled. We have considered the isotopic carbon fractionation of different carbon species involved in enhanced biodenitrification: external organic carbon, biomass, inorganic carbon (in different forms) and calcite. The inclusion of carbon isotopes in the model, which are involved in both direct (oxidation of organic carbon) and indirect (carbonate mineral interaction) processes of enhanced biodenitrification, improves the evaluation of the overall model consistency due to the central role of carbon in the reaction network.

  3. Multiwalled carbon nanotubes enhance electrochemical properties of titanium to determine in situ bone formation

    International Nuclear Information System (INIS)

    Multiwalled carbon nanotubes (MWCNTs) enhance osteoblast (bone-forming cell) calcium deposition compared to currently implanted materials (such as titanium). In this study, MWCNTs were grown out of nanopores anodized on titanium (MWCNT-Ti). The electrochemical responses of MWCNT-Ti were investigated in an attempt to ascertain if MWCNT-Ti can serve as novel in situ sensors of bone formation. For this purpose, MWCNT-Ti was subjected to a ferri/ferrocyanide redox couple and its electrochemical behavior measured. Cyclic voltammograms (CVs) showed an enhanced redox potential for the MWCNT-Ti. These redox signals were superior to that obtained with bare unmodified Ti, which did not sense either oxidation or reduction peaks in the CVs. A further objective of this study was to investigate the redox reactions of MWCNT-Ti in a solution of extracellular components secreted by osteoblasts in vitro. It was found that MWCNT-Ti exhibited well-defined and persistent CVs, similar to the ferri/ferrocyanide redox reaction. The higher electrodic performance and electrocatalytic activity of the MWCNT-Ti compared to the bare titanium observed in this study were likely due to the fact that MWCNTs enhanced direct electron transfer and facilitated double-layer effects, leading to a strong redox signal. Thus these results encourage the further study and modification of MWCNT-Ti to sense new bone growth in situ next to orthopedic implants and perhaps monitor other events (such as infection and/or harmful scar tissue formation) to improve the current clinical diagnosis of orthopedic implants

  4. Multiwalled carbon nanotubes enhance electrochemical properties of titanium to determine in situ bone formation

    Science.gov (United States)

    Sirivisoot, Sirinrath; Webster, Thomas J.

    2008-07-01

    Multiwalled carbon nanotubes (MWCNTs) enhance osteoblast (bone-forming cell) calcium deposition compared to currently implanted materials (such as titanium). In this study, MWCNTs were grown out of nanopores anodized on titanium (MWCNT-Ti). The electrochemical responses of MWCNT-Ti were investigated in an attempt to ascertain if MWCNT-Ti can serve as novel in situ sensors of bone formation. For this purpose, MWCNT-Ti was subjected to a ferri/ferrocyanide redox couple and its electrochemical behavior measured. Cyclic voltammograms (CVs) showed an enhanced redox potential for the MWCNT-Ti. These redox signals were superior to that obtained with bare unmodified Ti, which did not sense either oxidation or reduction peaks in the CVs. A further objective of this study was to investigate the redox reactions of MWCNT-Ti in a solution of extracellular components secreted by osteoblasts in vitro. It was found that MWCNT-Ti exhibited well-defined and persistent CVs, similar to the ferri/ferrocyanide redox reaction. The higher electrodic performance and electrocatalytic activity of the MWCNT-Ti compared to the bare titanium observed in this study were likely due to the fact that MWCNTs enhanced direct electron transfer and facilitated double-layer effects, leading to a strong redox signal. Thus these results encourage the further study and modification of MWCNT-Ti to sense new bone growth in situ next to orthopedic implants and perhaps monitor other events (such as infection and/or harmful scar tissue formation) to improve the current clinical diagnosis of orthopedic implants.

  5. In situ thermally enhanced biodegradation of petroleum fuel hydrocarbons and halogenated organic solvents

    International Nuclear Information System (INIS)

    An in situ thermally enhanced microbial remediation strategy and a method for the biodegradation of toxic petroleum fuel hydrocarbon and halogenated organic solvent contaminants are described. The method utilizes nonpathogenic, thermophilic bacteria for the thermal biodegradation of toxic and carcinogenic contaminants, such as benzene, toluene, ethylbenzene and xylenes, from fuel leaks and the chlorinated ethenes, such as trichloroethylene, chlorinated ethanes, such as 1,1,1-trichloroethane, and chlorinated methanes, such as chloroform, from past solvent cleaning practices. The method relies on and takes advantage of the pre-existing heated conditions and the array of delivery/recovery wells that are created and in place following primary subsurface contaminant volatilization efforts via thermal approaches, such as dynamic underground steam-electrical heating. 21 figs

  6. Changes in normal and abnormal colony formation of thyroid cells in vivo, when transplanted at 1 day or 6 weeks after X-irradiation in situ

    International Nuclear Information System (INIS)

    Thyroid cells were given 5.5 Gy X-rays in situ and transplanted after 1 day or after 6 weeks to form colonies in fat pads. The colony-forming efficiency unexpectedly decreased by a factor of about 2 with this increase in delay time before transplantation. In addition, there was a concomitant marked increase above the control levels in the proportion of new structures of thyroid origin containing abnormal follicles. These quantitative and qualitative increases in injury may be related to the gradual expression of thyroid abnormalities following irradiation in situ, and they may have implications for the recovery of functional tissue subunits in other organs. (author)

  7. Microbial and Chemical Enhancement of In-Situ Carbon Mineralization in Geological Formation

    Energy Technology Data Exchange (ETDEWEB)

    Matter, J.; Chandran, K.

    2013-05-31

    Predictions of global energy usage suggest a continued increase in carbon emissions and rising concentrations of CO{sub 2} in the atmosphere unless major changes are made to the way energy is produced and used. Various carbon capture and storage (CCS) technologies are currently being developed, but unfortunately little is known regarding the fundamental characteristics of CO{sub 2}-mineral reactions to allow a viable in-situ carbon mineralization that would provide the most permanent and safe storage of geologically-injected CO{sub 2}. The ultimate goal of this research project was to develop a microbial and chemical enhancement scheme for in-situ carbon mineralization in geologic formations in order to achieve long-term stability of injected CO{sub 2}. Thermodynamic and kinetic studies of CO{sub 2}-mineral-brine systems were systematically performed to develop the in-situ mineral carbonation process that utilizes organic acids produced by a microbial reactor. The major participants in the project are three faculty members and their graduate and undergraduate students at the School of Engineering and Applied Science and at the Lamont-Doherty Earth Observatory at Columbia University: Alissa Park in Earth and Environmental Engineering & Chemical Engineering (PI), Juerg Matter in Earth and Environmental Science (Co-PI), and Kartik Chandran in Earth and Environmental Engineering (Co-PI). Two graduate students, Huangjing Zhao and Edris Taher, were trained as a part of this project as well as a number of graduate students and undergraduate students who participated part-time. Edris Taher received his MS degree in 2012 and Huangjing Zhao will defend his PhD on Jan. 15th, 2014. The interdisciplinary training provided by this project was valuable to those students who are entering into the workforce in the United States. Furthermore, the findings from this study were and will be published in referred journals to disseminate the results. The list of the papers is given at the end of the report for reference.

  8. Broadband Cavity Enhanced Absorption Spectroscopy: an in-situ DOAS for Atmospheric Measurements

    Science.gov (United States)

    Langridge, J. M.; Le Crâne, J.; Ball, S. M.; Jones, R. L.

    2007-12-01

    From the processing of natural and anthropogenic emissions to the nucleation of new aerosol particles, tropospheric chemistry is driven by species present at trace concentrations. Field based observations provide the means to study complex trace gas processes in-situ, and advancements in understanding are often driven by developments in instrumentation that push forward the limits of sensitivity, target selectivity and deployment flexibility. In this work we present an ultra-sensitive optical instrument for quantification of a wide range of atmospheric trace gas components. The instrument is based upon a broadband variant of cavity enhanced absorption spectroscopy (BBCEAS) using high intensity light emitting diode sources, a short (1.1 m) high finesse optical cavity and wavelength resolved CCD detection. The BBCEAS approach enables measurements akin to those of traditional DOAS to be made in-situ and at high temporal resolution. This is important for the study of short lived species which show high spatial and temporal variability. In addition, the instrument offers deployment flexibility for field studies, being well suited for use on a range of platforms including aircraft, ships and vehicles. In this paper the instrument design and principles of operation will be described in detail, with particular attention being given to description of the calibration system. The performance of the instrument will be presented using results from a number of recent field and laboratory based studies. Most notably these include ppt level measurements of NO3 and N2O5 in coastal environments, ppt level detection of IO formed in reactor experiments from the oxidation of molecular iodine emitted from marine algae and lab based experiments showing sub ppb level detection of nitrous acid.

  9. In situ Raman and surface-enhanced Raman spectroscopy on working electrodes: spectroelectrochemical characterization of water oxidation electrocatalysts.

    Science.gov (United States)

    Joya, Khurram S; Sala, Xavier

    2015-09-01

    In situ Raman and surface-enhanced Raman scattering (SERS) are established vibrational spectroscopic techniques with a wide range of applications in the field of chemical, material and life sciences. Their particular characteristics make them especially useful when dealing with catalytic water oxidation at anodes. The in situ characterization of the fate of electrocatalysts (whether molecular or oxide materials) employed under reaction conditions is crucial to determine the chemical identity and the physical state of the actual catalytic species. Such studies also help in both, attaining mechanistic insights underlying the catalytic reaction and confirming/discarding the possibility of molecular to colloidal or heterogeneous phase conversions taking place prior or under turnover conditions. This perspective article highlights the use of in situ Raman and SERS as principal spectroscopic tools in the electrocatalysis field by means of recent contributions where they are employed to in operando characterize both molecular and oxide-based water oxidation electrocatalysts. These in situ spectroscopic measurements support in assessing both the progressive oxidation and the structural evolution of the employed catalytic species under electrochemical conditions. Therefore, this article provides an informative guideline for developing in situ spectroelectrochemical methods to study and characterize water oxidation catalysis at working anodes. PMID:25698502

  10. Field test for treatment verification of an in-situ enhanced bioremediation study

    International Nuclear Information System (INIS)

    Due to a leakage from a 12-inch pressurized diesel steel pipe four years ago, an area of approximately 30,000 square meters was contaminated. A pilot study applying the technology of in-situ enhanced bioremediation was conducted. In the study, a field test kit and on-site monitoring equipment were applied for site characterization and treatment verification. Physically, the enhanced bioremediation study consisted of an air extraction and air supply system, and a nutrition supply network. Certain consistent sampling methodology was employed. Progress was verified by daily monitoring and monthly verification. The objective of this study was to evaluate the capabilities of indigenous microorganisms to biodegrade the petroleum hydrocarbons with provision of oxygen and nutrients. Nine extraction wells and eight air sparging wells were installed. The air sparging wells injected the air into geoformation and the extraction wells provided the underground air circulation. The soil samples were obtained monthly for treatment verification by a Minuteman drilling machine with 2.5-foot-long hollow-stem augers. The samples were analyzed on site for TPH-diesel concentration by a field test kit manufactured by HNU-Hanby, Houston, Texas. The analytical results from the field test kit were compared with the results from an environmental laboratory. The TVPH concentrations of the air extracted from the vadose zone by a vacuum blower and the extraction wells were routinely monitored by a Foxboro FID and Cosmos XP-311A combustible air detector. The daily monitoring of TVPH concentrations provided the reliable data for assessing the remedial progress

  11. In-situ monitoring of potential enhanced DNA related processes using electrochemical quartz crystal microbalance with dissipation (EQCM-D)

    DEFF Research Database (Denmark)

    Quan, Xueling; Heiskanen, Arto

    2014-01-01

    The effect of applied potential pulses on DNA functionalization (thiolated single stranded DNA) and hybridization processes has been monitored in-situ on gold surfaces using electrochemical quartz crystal microbalance with dissipation (EQCM-D). The applied potentials were chosen with respect to the potential of zero charge (Epzc) of the gold surfaces: a positive potential to attract the negatively charged DNA molecules and a negative potential to enhance the vertical alignment due to electrostatic repulsion. The obtained results clearly show that both DNA modification and hybridization are strongly enhanced by applying potential pulses. Based on the EQCM-D results, we present a model to explain the influence of the potential pulsing. Aside fromthe effect of applied potentials on DNA related processes, this work also demonstrates the versatility of the combination of electrochemistry and quartz crystal microbalance with dissipation in facilitating real-time in situ monitoring of such processes.

  12. Enhanced spectroscopic gas sensors using in-situ grown carbon nanotubes

    Science.gov (United States)

    De Luca, A.; Cole, M. T.; Hopper, R. H.; Boual, S.; Warner, J. H.; Robertson, A. R.; Ali, S. Z.; Udrea, F.; Gardner, J. W.; Milne, W. I.

    2015-05-01

    In this letter, we present a fully complementary-metal-oxide-semiconductor (CMOS) compatible microelectromechanical system thermopile infrared (IR) detector employing vertically aligned multi-walled carbon nanotubes (CNT) as an advanced nano-engineered radiation absorbing material. The detector was fabricated using a commercial silicon-on-insulator (SOI) process with tungsten metallization, comprising a silicon thermopile and a tungsten resistive micro-heater, both embedded within a dielectric membrane formed by a deep-reactive ion etch following CMOS processing. In-situ CNT growth on the device was achieved by direct thermal chemical vapour deposition using the integrated micro-heater as a micro-reactor. The growth of the CNT absorption layer was verified through scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The functional effects of the nanostructured ad-layer were assessed by comparing CNT-coated thermopiles to uncoated thermopiles. Fourier transform IR spectroscopy showed that the radiation absorbing properties of the CNT adlayer significantly enhanced the absorptivity, compared with the uncoated thermopile, across the IR spectrum (3 ?m-15.5 ?m). This led to a four-fold amplification of the detected infrared signal (4.26 ?m) in a CO2 non-dispersive-IR gas sensor system. The presence of the CNT layer was shown not to degrade the robustness of the uncoated devices, whilst the 50% modulation depth of the detector was only marginally reduced by 1.5 Hz. Moreover, we find that the 50% normalized absorption angular profile is subsequently more collimated by 8°. Our results demonstrate the viability of a CNT-based SOI CMOS IR sensor for low cost air quality monitoring.

  13. Enhanced spectroscopic gas sensors using in-situ grown carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    De Luca, A.; Cole, M. T.; Milne, W. I. [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Hopper, R. H.; Boual, S.; Ali, S. Z. [Cambridge CMOS Sensors Ltd., Deanland House, 160 Cowley Road, Cambridge CB4 0DL (United Kingdom); Warner, J. H.; Robertson, A. R. [Department of Materials, University of Oxford, Oxford OX1 3PH (United Kingdom); Udrea, F. [Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Cambridge CMOS Sensors Ltd., Deanland House, 160 Cowley Road, Cambridge CB4 0DL (United Kingdom); Gardner, J. W. [School of Engineering, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2015-05-11

    In this letter, we present a fully complementary-metal-oxide-semiconductor (CMOS) compatible microelectromechanical system thermopile infrared (IR) detector employing vertically aligned multi-walled carbon nanotubes (CNT) as an advanced nano-engineered radiation absorbing material. The detector was fabricated using a commercial silicon-on-insulator (SOI) process with tungsten metallization, comprising a silicon thermopile and a tungsten resistive micro-heater, both embedded within a dielectric membrane formed by a deep-reactive ion etch following CMOS processing. In-situ CNT growth on the device was achieved by direct thermal chemical vapour deposition using the integrated micro-heater as a micro-reactor. The growth of the CNT absorption layer was verified through scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The functional effects of the nanostructured ad-layer were assessed by comparing CNT-coated thermopiles to uncoated thermopiles. Fourier transform IR spectroscopy showed that the radiation absorbing properties of the CNT adlayer significantly enhanced the absorptivity, compared with the uncoated thermopile, across the IR spectrum (3??m–15.5??m). This led to a four-fold amplification of the detected infrared signal (4.26??m) in a CO{sub 2} non-dispersive-IR gas sensor system. The presence of the CNT layer was shown not to degrade the robustness of the uncoated devices, whilst the 50% modulation depth of the detector was only marginally reduced by 1.5?Hz. Moreover, we find that the 50% normalized absorption angular profile is subsequently more collimated by 8°. Our results demonstrate the viability of a CNT-based SOI CMOS IR sensor for low cost air quality monitoring.

  14. Enhanced spectroscopic gas sensors using in-situ grown carbon nanotubes

    International Nuclear Information System (INIS)

    In this letter, we present a fully complementary-metal-oxide-semiconductor (CMOS) compatible microelectromechanical system thermopile infrared (IR) detector employing vertically aligned multi-walled carbon nanotubes (CNT) as an advanced nano-engineered radiation absorbing material. The detector was fabricated using a commercial silicon-on-insulator (SOI) process with tungsten metallization, comprising a silicon thermopile and a tungsten resistive micro-heater, both embedded within a dielectric membrane formed by a deep-reactive ion etch following CMOS processing. In-situ CNT growth on the device was achieved by direct thermal chemical vapour deposition using the integrated micro-heater as a micro-reactor. The growth of the CNT absorption layer was verified through scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The functional effects of the nanostructured ad-layer were assessed by comparing CNT-coated thermopiles to uncoated thermopiles. Fourier transform IR spectroscopy showed that the radiation absorbing properties of the CNT adlayer significantly enhanced the absorptivity, compared with the uncoated thermopile, across the IR spectrum (3??m–15.5??m). This led to a four-fold amplification of the detected infrared signal (4.26??m) in a CO2 non-dispersive-IR gas sensor system. The presence of the CNT layer was shown not to degrade the robustness of the uncoated devices, whilst the 50% modulation depth of the detector was only marginally reduced by 1.5?Hz. Moreover, we find that the 50% normalized absorption angular profile is subsequently more collimated by 8°. Our results demonstrate the viability of a CNT-based SOI CMOS IR sensor for low cost air quality monitoring

  15. In-situ monitoring of potential enhanced DNA related processes using electrochemical quartz crystal microbalance with dissipation (EQCM-D)

    DEFF Research Database (Denmark)

    Quan, Xueling; Heiskanen, Arto; Tenje, Maria; Boisen, Anja

    2014-01-01

    The effect of applied potential pulses on DNA functionalization (thiolated single stranded DNA) and hybridization processes has been monitored in-situ on gold surfaces using electrochemical quartz crystal microbalance with dissipation (EQCM-D). The applied potentials were chosen with respect to the potential of zero charge (Epzc) of the gold surfaces: a positive potential to attract the negatively charged DNA molecules and a negative potential to enhance the vertical alignment due to electrostat...

  16. Silver-enhanced in situ hybridization for detection of polyomavirus DNA in patients with BK virus nephropathy

    OpenAIRE

    Fritzsche, F R; Pianca, S; Gaspert, A; Varga, Z; WANG, L; Farrell, M P; Chen, X. B.; Hirsch, H. H.; Springer, E; Fehr, T; Myles, J; Tubbs, R; Moch, H

    2011-01-01

    BK virus nephropathy is not an infrequent complication of renal transplantation associated with high rates of graft loss. Although antibodies against SV40 antigen detect different viruses of the polyomavirus family, immunohistochemistry is widely used to confirm the diagnosis of BK virus nephropathy in renal biopsies. Here we aimed to validate the novel silver-enhanced in situ hybridization (SISH) technique for the automated detection of BK virus in renal transplant biopsies. Two different pa...

  17. Enhanced catalytic performance of carbon supported palladium nanoparticles by in-situ synthesis for formic acid electrooxidation

    Science.gov (United States)

    Yao, Shikui; Li, Guoqiang; Liu, Changpeng; Xing, Wei

    2015-06-01

    The development of facile, surfactant-free strategy for the scale-up production of catalysts with superior performance for energy science is an interesting challenge. Pd/C is synthesized using an in-situ method from PdO/C for formic acid electrooxidation based on the reducibility of formic acid. The morphology, composition and electrocatalytic properties are investigated using transmission electronmicroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, linear scan voltammograms (LSV) and chronoamperometry. The in-situ synthesized Pd nanoparticles show better distribution and smaller average particle size than the normally synthesized Pd/C, which indicates that the well-known Ostwald ripening is most limited in the synthesis process. The electrochemical measurements show that the Pd/C catalyst exhibits enhanced performance towards formic acid electrooxidation. For example, the peak current of the Pd/C catalyst is approximately three times that of the homemade Pd/C catalyst and twice as high as that of the commercial Pd/C catalyst in the LSV test. The in-situ synthesized Pd/C catalyst has potential application for direct formic acid fuel cells, and the in-situ route should be an effective strategy to synthesize high performance catalysts.

  18. Microcosm and in situ field studies of enhanced biotransformation of trichloroethylene by phenol-utilizing microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, G.D.; McCarty, P.L. (Stanford Univ., CA (United States)); Semprini, L. (Oregon State Univ., Corvallis (United States))

    1993-07-01

    Trichloroethylene (TCE) is the most frequently observed volatile organic contaminant at RCRA sites and in ground water. In situ aerobic bioremediation of aquifers contaminated with TCE, c-DCE, T-DCE, and vinyl chloride, is a potential means of restoring the aquifers. This study looks at field in situ data on chlorinated aliphatic hydrocarbon (CAH) transformation by indigenous microorganisms with a substrate other than methane in order to obtain a comparative evaluation of the effectiveness of different substrates for CAH transformation. Phenol was used for this study. The results indicate that with rapidly growing aerobic bacteria it is difficult to develop and maintain a uniform population in situ; however, bioremediation using micoorganisms grown on phenol is a possibility. 29 refs., 8 figs., 5 tabs.

  19. 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.

  20. Intermediates in the cation reactions in solution probed by an in situ surface enhanced Raman scattering method

    Science.gov (United States)

    Tan, Chih-Shan; Chen, Hung-Ying; Chen, Hsueh-Szu; Gwo, Shangjr; Chen, Lih-Juann

    2015-01-01

    For chemical reactions in liquid state, such as catalysis, understanding of dynamical changes is conducive to practical applications. Solvation of copper salts in aqueous solution has implications for life, the environment, and industry. In an ongoing research, the question arises that why the color of aqueous CuCl2 solution changes with solution concentration? In this work, we have developed a convenient and efficient in situ surface enhanced Raman scattering technique to probe the presence of many intermediates, some of them are responsible for color change, in crystallization of aqueous copper chloride solution. The versatility of the novel technique was confirmed in the identification of five intermediates states in the transition from CdS to MoS2 nanowires in solution. The facile in situ method is expected to be widely applicable in probing intermediate states in a variety of chemical reactions in solution. PMID:26333518

  1. Intermediates in the cation reactions in solution probed by an in situ surface enhanced Raman scattering method

    Science.gov (United States)

    Tan, Chih-Shan; Chen, Hung-Ying; Chen, Hsueh-Szu; Gwo, Shangjr; Chen, Lih-Juann

    2015-09-01

    For chemical reactions in liquid state, such as catalysis, understanding of dynamical changes is conducive to practical applications. Solvation of copper salts in aqueous solution has implications for life, the environment, and industry. In an ongoing research, the question arises that why the color of aqueous CuCl2 solution changes with solution concentration? In this work, we have developed a convenient and efficient in situ surface enhanced Raman scattering technique to probe the presence of many intermediates, some of them are responsible for color change, in crystallization of aqueous copper chloride solution. The versatility of the novel technique was confirmed in the identification of five intermediates states in the transition from CdS to MoS2 nanowires in solution. The facile in situ method is expected to be widely applicable in probing intermediate states in a variety of chemical reactions in solution.

  2. Label-free in-situ monitoring of protein tyrosine nitration in blood by surface-enhanced Raman spectroscopy.

    Science.gov (United States)

    Li, Yuan-Ting; Li, Da-Wei; Cao, Yue; Long, Yi-Tao

    2015-07-15

    A novel label-free method for the in-situ monitoring of protein tyrosine nitration (PTN) was explored based on surface-enhanced Raman spectroscopy (SERS). Benefiting from the relative weak binding ability of sulfate to silver surface, the Raman signals of nitrated peptides were boosted well with sulfate-aggregated silver nanoparticles (Ag NPs). The distinction of the SERS spectra between non-nitrated peptides and nitrated peptides was obtained by directly comparing SERS bands at 330-400cm(-1), allowing the rapid identification of PTN. Furthermore, without any pretreatments, the established method was successfully applied in the rapid in-situ dynamic monitoring of the mimic hemin-catalyzed PTN process in synthetic peptide, bovine serum albumin (BSA), and original human blood serum samples. The results indicated that the proposed approach could be a promising in-situ label-free tool for observing PTN process, which may be quite helpful to deeply understand the mechanism of post-translation modification. PMID:25703723

  3. In situ nitrogen-doped graphene grown from polydimethylsiloxane by plasma enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chundong; Zhou, Yungang; He, Lifang; Ng, Tsz-Wai; Hong, Guo; Wu, Qi-Hui; Gao, Fei; Lee, Chun-Sing; Zhang, Wenjun

    2013-01-21

    Due to its unique electronic properties and wide spectrum of promising applications, graphene has attracted much attention from scientists in various fields. Control and engineering of graphene’s semiconducting properties is considered to be the key of its applications in electronic devices. Here, we report a novel method to prepare in situ nitrogen-doped graphene by microwave plasma assisted chemical vapor deposition (CVD) using PDMS (Polydimethylsiloxane) as a solid carbon source. Based on this approach, the concentration of nitrogen-doping can be easily controlled via the flow rate of nitrogen during the CVD process. X-ray photoelectron spectroscopy results indicated that the nitrogen atoms doped into graphene lattice were mainly in the forms of pyridinic and pyrrolic structures. Moreover, first-principles calculations show that the incorporated nitrogen atoms can lead to p-type doping of graphene. This in situ approach provides a promising strategy to prepare graphene with controlled electronic properties.

  4. In situ nitrogen-doped graphene grown from polydimethylsiloxane by plasma enhanced chemical vapor deposition.

    Science.gov (United States)

    Wang, Chundong; Zhou, Yungang; He, Lifang; Ng, Tsz-Wai; Hong, Guo; Wu, Qi-Hui; Gao, Fei; Lee, Chun-Sing; Zhang, Wenjun

    2013-01-21

    Due to its unique electronic properties and wide spectrum of promising applications, graphene has attracted much attention from scientists in various fields. Control and engineering of graphene's semiconducting properties is considered to be key to its applications in electronic devices. Here, we report a novel method to prepare in situ nitrogen-doped graphene by microwave plasma assisted chemical vapor deposition (CVD) using PDMS (polydimethylsiloxane) as a solid carbon source. Based on this approach, the concentration of nitrogen-doping can be easily controlled via the flow rate of nitrogen during the CVD process. X-ray photoelectron spectroscopy results indicated that the nitrogen atoms doped into the graphene lattice were mainly in the forms of pyridinic and pyrrolic structures. Moreover, first-principles calculations show that the incorporated nitrogen atoms can lead to p-type doping of graphene. This in situ approach provides a promising strategy to prepare graphene with controlled electronic properties. PMID:23203220

  5. Enhanced visible-light induced degradation of benzene on Mg-ferrite/hematite/PANI nanospheres: In situ FTIR investigation

    International Nuclear Information System (INIS)

    Graphical abstract: The dramatic enhanced visible-light photocatalytic activity of Mg-ferrite/hematite nanospheres photocatalyst on benzene were obtained after hybridized by polyaniline (PANI) using the chemisorption method. The enhancement of photocatalytic degradation of benzene under visible-light irradiation was mainly ascribed to the high efficiency of charge separation induced by the hybrid effect of PANI and Mg-ferrite/hematite. By using the in situ FTIR technique, ethyl acetate, carboxylic acid and aldehyde could be regarded as the intermediate products, and CO2 is produced as the final product during the reaction process. Highlights: ? Mg-ferrite/hematite/PANI photocatalysts showed enhanced photocatalytic activity. ? Ethyl acetate, carboxylic acid and aldehyde were the intermediate products. ? CO2 was produced as the final product during the reaction process. ? The high efficiency of charge separation was mainly ascribed to the hybrid effect. - Abstract: The dramatic enhanced visible-light photocatalytic activity of Mg-ferrite/hematite nanospheres photocatalysts on benzene were obtained after hybridized by polyaniline (PANI) using the chemisorption method. The samples were characterized by scanning electron microscope, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectra and UV–Vis diffuse reflectance spectroscopy. The enhancement of photocatalytic degradation of benzene under visible-light irradiation was mainly ascribed to the high efficiency of charge separation induced by the hybrid effect of PANI and Mg-ferrite/hematite. By using the in situ FTIR technique, ethyl acetate, carboxylic acid and aldehyde could be regarded as the intermediate products, and CO2 is determined as the final product during the reaction process.

  6. Enhanced visible-light photocatalytic activities of Ag3PO4/MWCNT nanocomposites fabricated by facile in situ precipitation method

    International Nuclear Information System (INIS)

    Highlights: • Ag3PO4/MWCNT composites were facilely fabricated via in situ precipitation method. • Ag3PO4/MWCNT composites exhibited enhanced visible-light photocatalytic activity. • Ag3PO4/MWCNT composites showed good photostability compared with Ag3PO4 particles. • Possible photocatalytic mechanism under visible-light irradiation was proposed. - Abstract: The Ag3PO4/MWCNT nanocomposites were facilely fabricated via in situ precipitation method by adding (NH4)2HPO4 into the mixture of multi-walled carbon nanotube (MWCNT) and AgNO3 solution under stirring. The as-prepared Ag3PO4/MWCNT nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), the Brunauer–Emmett–Teller surface area (BET) and UV–vis diffuse reflectance spectroscopy. The TEM results showed that the Ag3PO4 nanoparticles were distributed on the surface of MWCNT uniformly with an average diameter of 70 nm, indicating excellent loading result. The photocatalytic activities of Ag3PO4/MWCNT nanocomposites were investigated by degrading methylene blue (MB) and malachite green (MG) under visible-light irradiation. It was found that the Ag3PO4/MWCNT nanocomposite exhibited excellent photocatalytic performance with enhanced photocatalytic efficiency and good photostability compared with bare Ag3PO4. Furthermore, a possible mechanism for the photocatalytic oxidative degradation was also discussed

  7. A capillary-based probe for in situ detection of enhanced fluorescence signals

    International Nuclear Information System (INIS)

    A simple, compact, and high sensitivity capillary-based probe for the in situ detection of fluorescence signals with high sensitivity is demonstrated. A home-made single–multi-mode fiber coupler that is coaxially aligned with the capillary-based probe provides for the transmission of excitation light and the collection and transmission of fluorescence. We propose a conceptually straightforward theoretical model to optimize the factors affecting the fluorescence-capture capability of the capillary-based probe. The fluorescence signal detected by fiber-optic spectroscopy non-linearly increases with the length of the capillary-based probe. In addition, the thicker the capillary tube wall is, the less the fluorescence signals determined are. The performance of the proposed probe is evaluated experimentally by measuring the fluorescence spectra of Cy5.5 dye and blue-green algae. The experimental results show that the proposed probe provides more than a ten-fold increase in fluorescence signal compared with direct measurements by a flat-tipped multi-mode fiber probe. The advantages of the capillary-based probe, which include its simple and compact structure, excellent light collection efficiency, requirement of small sample volume, and recoverability of samples, allow its wide application to in situ detection in the medical, forensic, biological, geological, and environmental fields with high sensitivity. (letter)

  8. Nitrogen removal characteristics of enhanced in situ indigenous aerobic denitrification bacteria for micro-polluted reservoir source water.

    Science.gov (United States)

    Zhou, Shilei; Huang, Tinglin; Zhang, Haihan; Zeng, Mingzheng; Liu, Fei; Bai, Shiyuan; Shi, Jianchao; Qiu, Xiaopeng; Yang, Xiao

    2016-02-01

    Indigenous oligotrophic aerobic denitrifiers nitrogen removal characteristics, community metabolic activity and functional genes were analyzed in a micro-polluted reservoir. The results showed that the nitrate in the enhanced system decreased from 1.71±0.01 to 0.80±0.06mg/L, while the control system did little to remove and there was no nitrite accumulation. The total nitrogen (TN) removal rate of the enhanced system reached 38.33±1.50% and the TN removal rate of surface sediment in the enhanced system reached 23.85±2.52%. TN removal in the control system experienced an 85.48±2.37% increase. The densities of aerobic denitrifiers in the enhanced system ranged from 2.24×10(5) to 8.13×10(7)cfu/mL. The abundance of nirS and nirK genes in the enhanced system were higher than those of in the control system. These results suggest that the enhanced in situ indigenous aerobic denitrifiers have potential applications for the bioremediation of micro-polluted reservoir system. PMID:26649898

  9. Long-term population dynamics and in situ physiology in activated sludge systems with enhanced biological phosphorus removal operated with and without nitrogen removal

    DEFF Research Database (Denmark)

    Lee, N.; Nielsen, P.H.; Aspegren, H.; Henze, Mogens; Schleifer, K.-H.; Jansen, J.l.C.

    2003-01-01

    Quantitative fluorescence in situ hybridization (FISH) and the combination of FISH with microautoradiography (MAR) were used in order to study the long-term population dynamics (2.5 years) and the in situ physiology in two parallel activated sludge pilot systems with enhanced biological phosphorus removal (EBPR). The two systems received the same influent wastewater, but were differently operated (with and without nitrogen removal, respectively). Both systems showed a significant P removal that ...

  10. In-Situ resonance-enhanced multiphoton ionization (REMPI) measurements using an optical fiber probe

    International Nuclear Information System (INIS)

    Two fiber-optic REMPI probes have been developed to determine the feasibility of using fiber-optics for in-situ determination of volatile organic compounds. In both designs, an optical fiber transmits a high-powered laser pulse to the sample, causing it to ionize, and the subsequent electrons are collected by a platinum electrode. One probe contains focusing optics while the other contains no focusing optics other than the fiber. Excitation using a 2+2 scheme was used for all measurements because visible excitation has optimal transmission of light through fiber-optics. The nonlensed probe was tested by measuring toluene and benzene and the response was compared to that using the lensed probe

  11. In-situ decorated gold nanoparticles on polyaniline with enhanced electrocatalysis toward dopamine

    International Nuclear Information System (INIS)

    Gold nanoparticles were in-situ decorated on top of a polyaniline film (GNPs-PANI) via the direct electroreduction of the adsorbed AuCl4- ions on a glassy carbon electrode that previously was coated with PANI by electropolymerization. The GNPs-PANI composite and the performance of the resultant sensors were investigated in some detail. The sensor was applied to the oxidation of dopamine (DA) with improved catalytic activity. Its catalytic current showed wide linear response toward dopamine ranging from 3 to 115 ?M, with a low detection limit of 0. 8 ?M (S/N=3). In addition, the sensor exhibits easy-operation, fast response to dopamine, as well as excellent reproducibility and stability. (author)

  12. Stable carbon isotope monitoring of in situ bioaugmentation for enhanced reductive dechlorination of halogenated hydrocarbons

    Science.gov (United States)

    Bill, M.; Conrad, M. E.; Sorenson, K.; Wymore, R.; Lamar, M.; Chamberlain, S.; Trotsky, J.

    2009-12-01

    Injection of electron donor to stimulate reductive dechlorination of trichloroethene (TCE) has been demonstrated to be an effective strategy for remediation of contaminated groundwater. At a number of sites, however, complete reductive dechlorination of TCE to ethene is not attained because the appropriate microbial community is not present. Addition of Dehalococcoides spp. to groundwater to achieve complete reductive dechlorination of TCE is being tested at Naval Weapons Station Seal Beach, CA. To help assess the effectiveness of this process, the stable carbon isotope compositions of TCE and its byproducts, cis-dichloroethene (cDCE), vinyl chloride (VC) and ethene are being measured during the experiment. Two different methods of bioremediation are being tested. In the “active” cell groundwater is continuously pumped from downgradient wells and re-injected into two upgradient wells. Electron donor (1-3% Na-lactate) has been added to the injection line either weekly or monthly. In the “passive” cell, no circulation of groundwater is done, but electron donor is added to three injection wells monthly. When reducing conditions were reached in the groundwater (late 2008), the bioaugmentation culture was added to both experimental cells with the electron donor. In the active cell, addition of electron donor prior to introduction of the bioaugmentation culture stimulated significant increases in the concentrations of cDCE, but only trace VC and ethene. In the passive cell, production of cDCE was observed, but at lower levels. The ?13C values of TCE ranged from -20‰ to 28‰ (averaging -24‰). The ?13C values of cDCE were generally 1-2‰ per mil lower than those of the TCE, representing fractionation during the biological conversion from TCE to cDCE. Following bioaugmentation, significant production of VC has been observed in the active cell, with corresponding increases in ?13C values of TCE and cDCE. In several wells, the ?13C values of the cDCE have become higher than that of the TCE, indicating efficient conversion of cDCE to VC. To date, only low levels of ethene have been observed in the active cell and this is reflected by the ?13C values of the VC, which are approaching the initial ?13C values of TCE. In the passive cell, dechlorination to VC is observed but less widespread than in the active cell. Where VC is observed, however, there is also significant production of ethene. The ?13C values of both cDCE and VC in these wells have been shifted to very high values (to as high as 1‰ for cDCE and -4‰ for VC) indicating significant levels of complete reductive dechlorination are occurring in this cell. The variations in the carbon isotope compositions of TCE and byproducts clearly indicate that bioaugmentation has led to significantly enhanced levels of reductive dechlorination at this site.

  13. In situ purity enhancement/surface modification of single-walled carbon nanotubes synthesized by induction thermal plasma

    International Nuclear Information System (INIS)

    A simple, cost-effective and energy-efficient approach was developed for in situ purity enhancement and surface modification of single-walled carbon nanotubes (SWCNTs) produced using an induction thermal plasma process. In this process, SWCNT-containing materials are thermally treated with oxygen flow inside a filtration chamber, while they are assembled into the sheets during the synthesis process. Owing to selective thermal oxidation, the amount of amorphous carbon was significantly reduced in the final product resulting in higher purity SWCNT-containing materials. Parametric study indicated that the amorphous carbon content was noticeably diminished in the product at an oxygen volume concentration of 10% in the synthesis system. Raman analysis indicated a decrease in the population of the SWCNTs with diameters smaller than 1.3 nm after in situ exposure to 10 vol.% of oxygen. In addition to the successful reduction of amorphous carbon content, the oxygen-functionalized SWCNTs were also observed in the final product using this process.

  14. In-situ gasification, enhanced methane recovery and CO{sub 2} storage in deep coal seams

    Energy Technology Data Exchange (ETDEWEB)

    James Hetherington; Kelly Thambimuthu [University of Sydney, Sydney, NSW (Australia)

    2003-07-01

    This paper examines the feasibility of combining a process known as in-situ or underground gasification with enhanced methane recovery to increase the permeability of coal seams, to extract energy and ultimately to store CO{sub 2} in seams that are too deep to mine. Permeability issues that affect gasification can be addressed through the use of a number of linking techniques that also have the potential to be applied to enhanced gas recovery. It is shown that the order in which gasification and enhanced gas recovery occur is important to the success of process combinations, as any carbon dioxide stored within the seam will dissociate from the coal matrix when exposed to the temperatures necessary for gasification. A highly concentrated environment of carbon dioxide would also have significant impact on gasification, requiring greater thermal or pure oxidant input. It is evident that whilst the combination of both techniques hold considerable potential, greater research into this field is needed as many of the mechanisms involved, especially in enhanced gas recovery, are not well understood. 27 refs.

  15. Semi-continuous in situ magnetic separation for enhanced extracellular protease productionmodeling and experimental validation

    DEFF Research Database (Denmark)

    Cerff, M.; Scholz, A.

    2013-01-01

    In modern biotechnology proteases play a major role as detergent ingredients. Especially the production of extracellular protease by Bacillus species facilitates downstream processing because the protease can be directly harvested from the biosuspension. In situ magnetic separation (ISMS) constitutes an excellent adsorptive method for efficient extracellular protease removal during cultivation. In this work, the impact of semi?continuous ISMS on the overall protease yield has been investigated. Results reveal significant removal of the protease from Bacillus licheniformis cultivations. Bacitracin?functionalized magnetic particles were successfully applied, regenerated and reused up to 30 times. Immediate reproduction of the protease after ISMS proved the biocompatibility of this integrated approach. Six subsequent ISMS steps significantly increased the overall protease yield up to 98% because proteolytic degradation and potential inhibition of the protease in the medium could be minimized. Furthermore, integration of semi?continuous ISMS increased the overall process efficiency due to reduction of the medium consumption. Process simulation revealed a deeper insight into protease production, and was used to optimize ISMS steps to obtain the maximum overall protease yield. Biotechnol. Bioeng. 2013; 110: 2161–2172. © 2013 Wiley Periodicals, Inc.

  16. Enhancing RHIC luminosity capabilities with in-situ beam piple coating

    Energy Technology Data Exchange (ETDEWEB)

    Herschcovitch,A.; Blaskiewicz, M.; Fischer, W.; Poole, H. J.

    2009-05-04

    Electron clouds have been observed in many accelerators, including the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory (BNL). They can limit the machine performance through pressure degradation, beam instabilities or incoherent emittance growth. The formation of electron clouds can be suppressed with beam pipe surfaces that have low secondary electron yield. At the same time, high wall resistivity in accelerators can result in levels of ohmic heating unacceptably high for superconducting magnets. This is a concern for the RHIC machine, as its vacuum chamber in the superconducting dipoles is made from relatively high resistivity 316LN stainless steel. The high resistivity can be addressed with a copper (Cu) coating; a reduction in the secondary electron yield can be achieved with a titanium nitride (TiN) or amorphous carbon (a-C) coating. Applying such coatings in an already constructed machine is rather challenging. We started developing a robotic plasma deposition technique for in-situ coating of long, small diameter tubes. The technique entails fabricating a device comprised of staged magnetrons and/or cathodic arcs mounted on a mobile mole for deposition of about 5 {micro}m (a few skin depths) of Cu followed by about 0.1 {micro}m of TiN (or a-C).

  17. Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Kathe, Mandar [Ohio State University, Columbus, OH (United States); Xu, Dikai [Ohio State University, Columbus, OH (United States); Hsieh, Tien-Lin [Ohio State University, Columbus, OH (United States); Simpson, James [Ohio State University, Columbus, OH (United States); Statnick, Robert [Ohio State University, Columbus, OH (United States); Tong, Andrew [Ohio State University, Columbus, OH (United States); Fan, Liang-Shih [Ohio State University, Columbus, OH (United States)

    2014-12-31

    This document is the final report for the project titled “Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture” under award number FE0012136 for the performance period 10/01/2013 to 12/31/2014.This project investigates the novel Ohio State chemical looping gasification technology for high efficiency, cost efficiency coal gasification for IGCC and methanol production application. The project developed an optimized oxygen carrier composition, demonstrated the feasibility of the concept and completed cold-flow model studies. WorleyParsons completed a techno-economic analysis which showed that for a coal only feed with carbon capture, the OSU CLG technology reduced the methanol required selling price by 21%, lowered the capital costs by 28%, increased coal consumption efficiency by 14%. Further, using the Ohio State Chemical Looping Gasification technology resulted in a methanol required selling price which was lower than the reference non-capture case.

  18. In-situ hybridization of calcium silicate and hydroxyapatite-gelatin nanocomposites enhances physical property and in vitro osteogenesis.

    Science.gov (United States)

    Chiu, Chi-Kai; Lee, Dong Joon; Chen, Hsin; Chow, Laurence C; Ko, Ching-Chang

    2015-02-01

    Low mechanical strengths and inadequate bioactive material-tissue interactions of current synthetic materials limit their clinical applications in bone regeneration. Here, we demonstrate gelatin modified siloxane-calcium silicate (GEMOSIL-CS), a nanocomposite made of gelatinous hydroxyapatite with in situ pozzolanic formation of calcium silicate (CS) interacting among gelatin, silica and Calcium Hydroxide (Ca(OH)2). It is shown the formation of CS matrices, which chemically bonds to the gelatinous hydroxyapatite, provided hygroscopic reinforcement mechanism and promoted both in vitro and in vivo osteogenic properties of GEMOSIL-CS. The formation of CS was identified by Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction. The interfacial bindings within nanocomposites were studied by FTIR and thermogravimetric analysis. Both gelatin and CS have been found critical to the structure integrity and mechanical strengths (93 MPa in compressive strength and 58.9 MPa in biaxial strength). The GEMOSIL-CS was biocompatible and osteoconductive as result of type I collagen secretion and mineralized nodule formation from MC3T3 osteoblasts. SEM and TEM indicated the secretion of collagen fibers and mineral particles as the evidence of mineralization in the early stage of osteogenic differentiation. In vivo bone formation capability was performed by implanting GEMOSIL-CS into rat calvarial defects for 12 weeks and the result showed comparable new bone formation between GEMOSIL-CS group (20%) and the control (20.19%). The major advantage of GEMOSIL-CS composites is in situ self-hardening in ambient or aqueous environment at room temperature providing a simple, fast and cheap method to produce porous scaffolds. PMID:25649517

  19. Evaluation of Immunohistochemistry and Silver-Enhanced In Situ Hybridization Results for HER2/neu Manually and with Image Analysis System in Human Breast Cancer

    Directory of Open Access Journals (Sweden)

    Do?u? ÖZDEM?R

    2010-09-01

    Full Text Available Objective: HER2/neu (ErbB2 gene status is one of the important information while planing terapy in breast carcinoma. For HER2/ neu testing there is not standart assay that has been agreed on. Silver enhanced in situ hybridization is a cantitative and highly reproducible assay. Immunohistochemistry is a cheap and easy assay that has disadvantage of being less reproducible. Recently developed pathologist assisted computerized image analysis systems decrease the ratio of subjectivity due to manual evaluation, enable tele-consultation and make it easy to evaluate tumor morphology and markers. Our aim is to investigate the consistency of manual and computerized interpretation of the results of immunohistochemistry and silver enhanced in situ hybridization.Material and Method: Immunohistochemisty and silver enhanced in situ hybridization of 73 invasive breast carcinoma results were evaluated manually to determine HER2/neu status. Later, silver enhanced in situ hybridization and immunohistochemistry results were reevaluated with Ventana Image Analysis System. Afterwards correlation of both methods with image analysis system and manuel interpretation were calculated.Result: All cases were score 2 with immunohistochemistry. With image analysis system, 5 cases were score 1, 56 cases were score 2 and 12 cases were score 3. When in situ hybridization results were reevaluated with image analysis system, 6 cases were discordant compared with manual interpretation.Conclusion: The correlation rate of immunohistochemistry interpretation results between manuel method and image analysis system was %76; but silver enhanced in situ hybridization interpretation results between manuel method and image analysis system were %91 concordant and it was statistically significant (k= 0.832 and p<0.001.

  20. 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.

  1. Surface-enhanced in-situ Raman-sensor applied in the arctic area for analyses of water and sediment

    Science.gov (United States)

    Kolomijeca, Anna; Kwon, Yong-Hyok; Kronfeldt, Heinz-Detlef

    2012-06-01

    Investigations on the seafloor in the arctic area are of great scientific interest as well as of progressive economic importance. Therefore, measurements in the water column and of sediments were carried out by applying different analytical methods. In JCR 253 arctic cruise a microsystem diode laser with reflection Bragg grating emitting at 671 nm was introduced and integrated into an optode housing which was laboratory pressure tested up to 200 bar. The connection to the mobile spectrometer is realized through an optical fiber. All performed measurements were carried out on the James-Clark-Ross research vessel during a three week experiment in August 2011. Conventional Raman spectra and SERS spectra of arctic surface water and sediment acquired from locations around 78° N and 9° E will be presented. Selected SERS substrates developed for SERS measurements in sea-water were tested for their capability to detect different substances in the water down to very small (pmol/l) concentrations. Additionally, the applicability of shifted excitation Raman difference spectroscopy (SERDS) and a combination of SERS with SERDS for analytical applications during sea-trials for in-situ analyses of sea-water and sediments will be discussed.

  2. Enhanced photoelectrochemical performance of WO3/Ti photoanode due to in situ formation of a thin interfacial composite layer

    International Nuclear Information System (INIS)

    Nanostructured WO3 thin films were prepared on titanium sheet substrates using a doctor blade technique. X-ray diffraction, Raman and field emission scanning electron microscopy studies revealed that the synthesized WO3 films are having monoclinic crystal structure, porous, polycrystalline with average grain size of ?50 nm. The photoelectrochemical responses of WO3 films prepared on treated Ti sheets were recorded in 0.5 M H2SO4 electrolyte under simulated 100 mW/cm2 illumination. WO3 film prepared on polished Ti sheet showed considerable enhancement in photocurrent as compared to WO3 films made on unpolished and pre-oxidized Ti sheets. These results suggest that in situ formation of a thin WOx–TiOy interfacial composite layer and improved adhesion of WO3 nanoparticles owing to increased reactive sites on polished Ti substrate play a significant role in enhancing the photoresponse. Such photoanodes are potential candidates in photoelectrochemical water splitting system for hydrogen generation.

  3. Strong enhancement of Jc and Birr in binary in situ MgB2 wires after cold high pressure densification

    International Nuclear Information System (INIS)

    Cold high pressure densification was found to substantially enhance the critical current density of binary in situ Fe/MgB2 wires. A wire densified at 1.85 GPa exhibited at 20 K and 5 T an increase of Jc by 300% with respect to same wire without the application of pressure. At 4.2 K and 10 T, Jc was found to be increased by 53%. The decrease of the electrical resistance for densified wires reflects an improved connectivity. The values of Birr at 4.2 and 20 K were enhanced up to 0.7 T for densified wires. After applying pressures up to 6.5 GPa at 300 K, the relative mass density dm of the unreacted (B+Mg) mixture inside the filament increased up to 96% of the theoretical density. This corresponds to a relative mass density df in the reacted MgB2 filaments of 73%. A quantitative correlation between filament mass density and critical current density was established.

  4. In Situ Integration of Anisotropic SnO2 Heterostructures inside Three-Dimensional Graphene Aerogel for Enhanced Lithium Storage.

    Science.gov (United States)

    Yao, Xin; Guo, Guilue; Ma, Xing; Zhao, Yang; Ang, Chung Yen; Luo, Zhong; Nguyen, Kim Truc; Li, Pei-Zhou; Yan, Qingyu; Zhao, Yanli

    2015-12-01

    Three-dimensional (3D) graphene aerogel (GA) has emerged as an outstanding support for metal oxides to enhance the overall energy-storage performance of the resulting hybrid materials. In the current stage of the studies, metals/metal oxides inside GA are in uncrafted geometries. Introducing structure-controlled metal oxides into GA may further push electrochemical properties of metal oxide-GA hybrids. Using rutile SnO2 as an example, we demonstrated here a facile hydrothermal strategy combined with a preconditioning technique named vacuum-assisted impregnation for in situ construction of controlled anisotropic SnO2 heterostructures inside GA. The obtained hybrid material was fully characterized in detail, and its formation mechanism was investigated by monitoring the phase-transformation process. Rational integration of the two advanced structures, anisotropic SnO2 and 3D GA, synergistically led to enhanced lithium-storage properties (1176 mAh/g for the first cycle and 872 mAh/g for the 50th cycle at 100 mA/g) as compared with its two counterparts, namely, rough nanoparticles@3D GA and anisotropic SnO2@2D graphene sheets (618 and 751 mAh/g for the 50th cycle at 100 mA/g, respectively). It was also well-demonstrated that this hybrid material was capable of delivering high specific capacity at rapid charge/discharge cycles (1044 mAh/g at 100 mA/g, 847 mAh/g at 200 mA/g, 698 mAh/g at 500 mA/g, and 584 mAh/g at 1000 mA/g). The in situ integration strategy along with vacuum-assisted impregnation technique presented here shows great potential as a versatile tool for accessing a variety of sophisticated smart structures in the form of anisotropic metals/metal oxides within 3D GA toward useful applications. PMID:26554275

  5. Nano-socketed nickel particles with enhanced coking resistance grown in situ by redox exsolution

    Science.gov (United States)

    Neagu, Dragos; Oh, Tae-Sik; Miller, David N.; Ménard, Hervé; Bukhari, Syed M.; Gamble, Stephen R.; Gorte, Raymond J.; Vohs, John M.; Irvine, John T. S.

    2015-09-01

    Metal particles supported on oxide surfaces are used as catalysts for a wide variety of processes in the chemical and energy conversion industries. For catalytic applications, metal particles are generally formed on an oxide support by physical or chemical deposition, or less commonly by exsolution from it. Although fundamentally different, both methods might be assumed to produce morphologically and functionally similar particles. Here we show that unlike nickel particles deposited on perovskite oxides, exsolved analogues are socketed into the parent perovskite, leading to enhanced stability and a significant decrease in the propensity for hydrocarbon coking, indicative of a stronger metal-oxide interface. In addition, we reveal key surface effects and defect interactions critical for future design of exsolution-based perovskite materials for catalytic and other functionalities. This study provides a new dimension for tailoring particle-substrate interactions in the context of increasing interest for emergent interfacial phenomena.

  6. In situ fluorescent protein imaging with metal film-enhanced total internal reflection microscopy.

    Science.gov (United States)

    Burghardt, Thomas P; Charlesworth, Jon E; Halstead, Miriam F; Tarara, James E; Ajtai, Katalin

    2006-06-15

    Fluorescence detection of single molecules provides a means to investigate protein dynamics minus ambiguities introduced by ensemble averages of unsynchronized protein movement or of protein movement mimicking a local symmetry. For proteins in a biological assembly, taking advantage of the single molecule approach could require single protein isolation from within a high protein concentration milieu. Myosin cross-bridges in a muscle fiber are proteins attaining concentrations of approximately 120 muM, implying single myosin detection volume for this biological assembly is approximately 1 attoL (10(-18) L) provided that just 2% of the cross-bridges are fluorescently labeled. With total internal reflection microscopy (TIRM) an exponentially decaying electromagnetic field established on the surface of a glass-substrate/aqueous-sample interface defines a subdiffraction limit penetration depth into the sample that, when combined with confocal microscopy, permits image formation from approximately 3 attoL volumes. Demonstrated here is a variation of TIRM incorporating a nanometer scale metal film into the substrate/glass interface. Comparison of TIRM images from rhodamine-labeled cross-bridges in muscle fibers contacting simultaneously the bare glass and metal-coated interface show the metal film noticeably reduces both background fluorescence and the depth into the sample from which fluorescence is detected. High contrast metal film-enhanced TIRM images allow secondary label visualization in the muscle fibers, facilitating elucidation of Z-disk structure. Reduction of both background fluorescence and detection depth will enhance TIRM's usefulness for single molecule isolation within biological assemblies. PMID:16565065

  7. in Situ Formation of a Biocatalytic Alginate Membrane by Enhanced Concentration Polarization

    DEFF Research Database (Denmark)

    Marpani, Fauziah; Luo, Jianquan

    2015-01-01

    A thin alginate layer induced on the surface of a commercial polysulfone membrane was used as a matrix for noncovalent immobilization of enzymes. Despite the expected decrease of flux across the membrane resulting from the coating, the initial hypothesis was that such a system should allow high immobilized enzyme loadings, which would benefit from the decreased flux in terms of increased enzyme/substrate contact time. The study was performed in a sequential fashion: first, the most suitable types of alginate able to induce a very thin, sustainable gel layer by pressure-driven membrane filtration were selected and evaluated. Then, an efficient method to make the gel layer adhere to the surface of the membrane was developed. Finally, and after confirming that the enzyme loading could remarkably be enhanced by using this method, several strategies to increase the permeate flux were evaluated. Alcohol dehydrogenase (EC 1.1.1.1), able to catalyze the conversion of formaldehyde into methanol, was selected as the model enzyme. An enzyme loading of 71.4% (44.8 ?g/cm2) was attained under the optimal immobilization conditions, which resulted in a 40% conversion to methanol as compared to the control setup (without alginate) where only 10.8% (6.9 ?g/cm2) enzyme was loaded, with less than 5% conversion. Such conversion increased to 60% when polyethylene glycol (PEG) was added during the construction of the gel layer, as a strategy to increase flux. No enzyme leakage was observed for both cases (with/without PEG addition). Modeling results showed that the dominant fouling mechanism during gel layer induction (involving enzyme entrapment) was cake layer formation in the initial and intermediate phases, while pore blocking was the dominant mechanism in the final phase. Such mechanisms had a direct consequence on the type of immobilization promoted in each phase. The results suggested that the strategy proposed could be efficiently used to enhance the enzyme loading on polymer membranes.

  8. Optical engineering of uniformly decorated graphene oxide nanoflakes via in situ growth of silver nanoparticles with enhanced plasmonic resonance.

    Science.gov (United States)

    Yuan, Kai; Chen, Lie; Chen, Yiwang

    2014-12-10

    A nanocomposite of silver-nanoparticle-decorated graphene oxide (GO-Ag NPs), enhanced by the surface plasmon resonance (SPR) effect, improved the performance of polymer solar cells (PSCs). The GO-Ag NPs were fabricated in situ via ultraviolet (UV) irradiation (254 nm) of GO and an aqueous solution of AgNO3. The photoexcited GO accelerated reduction of Ag(+) ions into silver nanoparticles (Ag NPs) upon UV irradiation, and the Ag NPs spontaneously deposited on the GO nanoflakes because the numerous functional groups on GO enable efficient adsorption of Ag(+) ions and Ag NPs via electrostatic interactions. The strong coupling between the SPR effect of GO-Ag NPs and incident light offers the probability of improved light absorption and corresponding exciton generation rate with enhanced charge collection, resulting in significant enhancement in short-circuit current density and power conversion efficiency (PCE). Therefore, the PCE of PSCs based on poly[4,8-bis(2-ethylhexylthiophene-5-yl)-benzo[1,2-b:4,5-b]dithiophene-2,6-diyl]-alt-[2-(2-ethylhexanoyl)thieno[3,4-b]thiophen-4,6-diyl] and [6,6]-phenyl C71-butyric acid methyl ester has been substantially elevated to 7.54% from 6.58% by introducing GO-Ag NPs at the indium tin oxide/poly(3,4-ethylenedioxythiophene):polystyrene sulfonic acid interface. In addition, the excellent properties of GO-Ag NPs, including its simple preparation, processability in aqueous solution, cost-effectiveness, and sustainability, make it suitable for the roll-to-roll manufacturing of PSCs. PMID:25389764

  9. Development of an In Situ Biosurfactant Production Technology for Enhanced Oil Recovery

    Energy Technology Data Exchange (ETDEWEB)

    M.J. McInerney; R.M. Knapp; Kathleen Duncan; D.R. Simpson; N. Youssef; N. Ravi; M.J. Folmsbee; T.Fincher; S. Maudgalya; Jim Davis; Sandra Weiland

    2007-09-30

    The long-term economic potential for enhanced oil recovery (EOR) is large with more than 300 billion barrels of oil remaining in domestic reservoirs after conventional technologies reach their economic limit. Actual EOR production in the United States has never been very large, less than 10% of the total U. S. production even though a number of economic incentives have been used to stimulate the development and application of EOR processes. The U.S. DOE Reservoir Data Base contains more than 600 reservoirs with over 12 billion barrels of unrecoverable oil that are potential targets for microbially enhanced oil recovery (MEOR). If MEOR could be successfully applied to reduce the residual oil saturation by 10% in a quarter of these reservoirs, more than 300 million barrels of oil could be added to the U.S. oil reserve. This would stimulate oil production from domestic reservoirs and reduce our nation's dependence on foreign imports. Laboratory studies have shown that detergent-like molecules called biosurfactants, which are produced by microorganisms, are very effective in mobilizing entrapped oil from model test systems. The biosurfactants are effective at very low concentrations. Given the promising laboratory results, it is important to determine the efficacy of using biosurfactants in actual field applications. The goal of this project is to move biosurfactant-mediated oil recovery from laboratory investigations to actual field applications. In order to meet this goal, several important questions must be answered. First, it is critical to know whether biosurfactant-producing microbes are present in oil formations. If they are present, then it will be important to know whether a nutrient regime can be devised to stimulate their growth and activity in the reservoir. If biosurfactant producers are not present, then a suitable strain must be obtained that can be injected into oil reservoirs. We were successful in answering all three questions. The specific objectives of the project were (1) to determine the prevalence of biosurfactant producers in oil reservoirs, and (2) to develop a nutrient regime that would stimulate biosurfactant production in the oil reservoir.

  10. In situ synthesis of zeolitic imidazolate frameworks/carbon nanotube composites with enhanced CO? adsorption.

    Science.gov (United States)

    Yang, Ying; Ge, Lei; Rudolph, Victor; Zhu, Zhonghua

    2014-05-21

    A series of ZIF-8 and hydroxyl-functionalized carbon nanotube (CNT) composites were successfully synthesized by the solvothermal method. The obtained ZIF-8/CNT composites were characterized by XRD, SEM, TGA and N2 adsorption at 77 K. The contents of ZIF-8 and CNTs in the composites were calculated from thermal analysis data. CO2 and N2 adsorption at 273 K on the composites was also investigated and compared. The ZIF-8 particles in the composites exhibit similar crystal structures and morphology to those of pure ZIF-8, but display enhanced thermal stability. The surface areas and pore volumes of the ZIF-8/CNT composites are higher than the values calculated for hypothetical physical mixtures, and the synergetic effect between ZIF-8 and CNTs can be proposed. This phenomenon demonstrates that the incorporation of CNTs into ZIF-8 can facilitate the nucleation and crystallization of ZIF-8. As a result, the composites with an optimal CNT content (3.63 wt%) show improved CO2 adsorption capacity and higher relative selectivity for CO2/N2 compared with pure ZIF-8. PMID:24676235

  11. In-situ sonication for enhanced recovery of aquifer microbial communities.

    Science.gov (United States)

    Ugolini, Fabio; Henneberger, Ruth; Bürgmann, Helmut; Zeyer, Josef; Schroth, Martin H

    2014-01-01

    Sampling methods for characterization of microbial communities in aquifers should target both suspended and attached microorganisms (biofilms). We investigated the effectiveness and reproducibility of low-frequency (200 Hz) sonication pulses on improving extraction efficiency and quality of microorganisms from a petroleum-contaminated aquifer in Studen (Switzerland). Sonication pulses at different power levels (0.65, 0.9, and 1.1 kW) were applied to three different groundwater monitoring wells. Groundwater samples extracted after each pulse were compared with background groundwater samples for cell and adenosine tri-phosphate concentration. Turbidity values were obtained to assess the release of sediment fines and associated microorganisms. The bacterial community in extracted groundwater samples was analyzed by terminal-restriction-fragment-length polymorphism and compared with communities obtained from background groundwater samples and from sediment cores. Sonication enhanced the extraction efficiency up to 13-fold, with most of the biomass being associated with the sediment fines extracted with groundwater. Consecutive pulses at constant power were decreasingly effective, while pulses with higher power yielded the best results both in terms of extraction efficiency and quality. Our results indicate that low-frequency sonication may be a viable and cost-effective tool to improve the extraction of microorganisms from aquifers, taking advantage of existing groundwater monitoring wells. PMID:23937340

  12. In situ stimulation vs. bioaugmentation: Can microbial inoculation of plant roots enhance biodegradation of organic compounds?

    Energy Technology Data Exchange (ETDEWEB)

    Kingsley, M.T.; Metting, F.B. Jr.; Fredrickson, J.K. [Pacific Northwest Lab., Richland, WA (United States); Seidler, R.J. [Environmental Protection Agency, Corvallis, OR (United States). Environmental Research Lab.

    1993-06-01

    The use of plant roots and their associated rhizosphere bacteria for biocontainment and biorestoration offers several advantages for treating soil-dispersed contaminants and for application to large land areas. Plant roots function as effective delivery systems, since root growth transports bacteria vertically and laterally along the root in the soil column (see [ 1,2]). Movement of microbes along roots and downward in the soil column can be enhanced via irrigation [1-4]. For example, Ciafardini et al. [3] increased the nodulation and the final yield of soybeans during pod filling by including Bradyrhizobium japonicum in the irrigation water. Using rhizosphere microorganisms is advantageous for biodegradation of compounds that are degraded mainly by cometabolic processes, e.g., trichloroethylene (TCE). The energy source for bacterial growth and metabolism is supplied by the plant in the form of root exudates and other sloughed organic material. Plants are inexpensive, and by careful choice of species that possess either tap or fibrous root growth patterns, they can be used to influence mass transport of soil contaminants to the root surface via the transpiration stream [5]. Cropping of plants to remove heavy metals from contaminated soils has been proposed as a viable, low-cost, low-input treatment option [6]. The interest in use of plants as a remediation strategy has even reached the popular press [7], where the use of ragweed for the reclamation of sites contaminated with tetraethyl lead and other heavy metals was discussed.

  13. Surface-enhanced Raman Scattering (SERS) for in-situ Analysis of Mixture of Polycyclic Aromatic Hydrocarbons (PAHs) in Sea-water

    OpenAIRE

    Nguyen Thi, Bich Ha

    2004-01-01

    Diese Untersuchung soll Beiträge für die Entwicklung einer empfindlichen Methode für den Nachweis und die quantitative Bestimmung polyzyklischer aromatischer Kohlenwasserstoffe (polycyclic aromatic hydrocarbons, PAHs) im Meerwasser liefern, die auf der Anwendung der sog. oberflächenverstärkten Raman Streuung (surface-enhanced Raman scattering, SERS) ba-siert. Eine in-situ Messung der PAH-Konzentrationen direkt im Meer ist von großer praktischer Bedeutung, da viele PAHs bei Mensch und Tier Kre...

  14. In situ formation of nanocrystals from a self-microemulsifying drug delivery system to enhance oral bioavailability of fenofibrate

    Directory of Open Access Journals (Sweden)

    Lin YM

    2011-10-01

    Full Text Available You-Meei Lin1, Jui-Yu Wu2, Ying-Chen Chen3, Yu-Der Su3, Wen-Tin Ke3, Hsiu-O Ho31Department of Pharmacy, Shuang Ho Hospital, 2Department of Biochemistry, School of Medicine, 3School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan, ROCObjectives: In situ formation of nanocrystals and dissolution profiles of fenofibrate (FFB from a self-microemulsifying drug delivery system (SMEDDS were characterized.Methods: SMEDDS formulated with Myritol® and surfactant mixture (Smix of D-?-Tocopheryl polyethylene glycol 1000 succinate (TPGS and either Tween® 20 (A, C, E, G, M, S, N, T, O or Tween® 80 (B, D, F, H, P, U, Q, V, R at various oil/Smix ratios (Group I: A and B of 0.42, C and D of 0.25, E and F of 0.11; Group II: G and H of 1.38, M and P of 1.11, S and U of 0.9, N and Q of 0.73, T and V of 0.58, and O and R of 0.46 and water contents (1: 9.5%, 2: 5.0%, 3: 0.0%, G-V: 4.5%. Their dissolutions were conducted at different rotation speeds. Two optimal SMEDDSs containing Tween 80(B2 or a higher oil/Smix ratio(Q and B2(solution were selected for pharmacokinetic study.Results: FFB particles formed within the nanosize range from Group I gradually increased with time but decreased with increasing stirring rates. However, the mean size of FFB formed by B series was as low as 200 nm, which was smaller than that of A series at three stirring rates. The release rate from both groups obviously increased with increasing stirring rate. However, incomplete release was observed for S and N in Tween 20 series, whereas a faster release rate and complete release were observed for Tween 80 series with an insignificant difference among them. Results of pharmacokinetic study demonstrated that the highest-ranked area under the curve and Cmax values were for Q(SMEDDS and B2(solution, respectively. The relative bioavailability of Q(SMEDDS with respect to Tricor® was enhanced by about 1.14-1.22-fold.Conclusion: SMEDDS, consisting of Myritol 318 and TPGS combined with Tween 80 at 4:1, was able to enhance the oral bioavailability of FFB.Keywords: SMEDDS, fenofibrate, microemulsion, dissolution, TPGS

  15. Large upper tropospheric ozone enhancements above midlatitude North America during summer: In situ evidence from the IONS and MOZAIC ozone measurement network

    Science.gov (United States)

    Cooper, O. R.; Stohl, A.; Trainer, M.; Thompson, A. M.; Witte, J. C.; Oltmans, S. J.; Morris, G.; Pickering, K. E.; Crawford, J. H.; Chen, G.; Cohen, R. C.; Bertram, T. H.; Wooldridge, P.; Perring, A.; Brune, W. H.; Merrill, J.; Moody, J. L.; Tarasick, D.; NéDéLec, P.; Forbes, G.; Newchurch, M. J.; Schmidlin, F. J.; Johnson, B. J.; Turquety, S.; Baughcum, S. L.; Ren, X.; Fehsenfeld, F. C.; Meagher, J. F.; Spichtinger, N.; Brown, C. C.; McKeen, S. A.; McDermid, I. S.; Leblanc, T.

    2006-12-01

    The most extensive set of free tropospheric ozone measurements ever compiled across midlatitude North America was measured with daily ozonesondes, commercial aircraft and a lidar at 14 sites during July-August 2004. The model estimated stratospheric ozone was subtracted from all profiles, leaving a tropospheric residual ozone. On average the upper troposphere above midlatitude eastern North America contained 15 ppbv more tropospheric residual ozone than the more polluted layer between the surface and 2 km above sea level. Lowest ozone values in the upper troposphere were found above the two upwind sites in California. The upper troposphere above midlatitude eastern North America contained 16 ppbv more tropospheric residual ozone than the upper troposphere above three upwind sites, with the greatest enhancement above Houston, Texas, at 24 ppbv. Upper tropospheric CO measurements above east Texas show no statistically significant enhancement compared to west coast measurements, arguing against a strong influence from fresh surface anthropogenic emissions to the upper troposphere above Texas where the ozone enhancement is greatest. Vertical mixing of ozone from the boundary layer to the upper troposphere can only account for 2 ppbv of the 16 ppbv ozone enhancement above eastern North America; therefore the remaining 14 ppbv must be the result of in situ ozone production. The transport of NOx tracers from North American anthropogenic, biogenic, biomass burning, and lightning emissions was simulated for the upper troposphere of North America with a particle dispersion model. Additional box model calculations suggest the 24 ppbv ozone enhancement above Houston can be produced over a 10 day period from oxidation reactions of lightning NOx and background mixing ratios of CO and CH4. Overall, we estimate that 69-84% (11-13 ppbv) of the 16 ppbv ozone enhancement above eastern North America is due to in situ ozone production from lightning NOx with the remainder due to transport of ozone from the surface or in situ ozone production from other sources of NOx.

  16. In-situ treatment of hydrocarbons contamination through enhanced bio-remediation and two phase extraction system

    International Nuclear Information System (INIS)

    It happens frequently to find industrial site affected by contamination of subsoil and groundwater with consequent presence of free phase product floating on the water table. The remediation technologies in this case shall be properly selected and coordinated in a way that the interactions between each activities will help to decontaminate the site. The case study deals with an industrial site located near Turin, in Italy, of about 50 hectares of extension where has been found an area of about 4000 square meters with contamination of subsoil and groundwater. The compounds with higher concentrations are petroleum hydrocarbons found both in soil and in groundwater. Another big problem is represented by the presence of a layer of free product floating on the water table with a maximum measured thickness of 70 cm; this situation can be considered in fact one of the major difficulty in management of selected remediation technologies because the complete recover of the free phase is a priority for any kind of remediation system to apply subsequently. The present work is based upon the selection and implementation of a multiple treatment for definitive remediation of subsoil and groundwater. Free product recovery has been faced with a two-phase extraction technology, then for the remediation of subsoil we implemented a bio-venting system to improve biodegradation processes and finally for groundwater treatment we apply an enhanced in situ bio-remediation injecting oxygen release compounds directly into the aquifer. To reach these choices we have to pass through a complex activity of investigation of the site made up of more than 40 sampling point, 8 monitoring wells, about 140 analysis on subsoil samples and 10 on groundwater samples and one well used for an aquifer test. The preliminary design of the remediation system was therefore based on an extensive site characterization that included geological and geochemical, microbiological and hydrological data, together with analytical data. After the study of all data acquired during investigations we could select the proper technologies for site remediation but to define correctly all project data we had to implement several laboratory tests to analyse bio-remediation processes, a series of pilot test for two phase extraction and bio-venting and a pilot test to select the best product for the release of oxygen into groundwater. The collection of the necessary parameters for the implementation of full-scale treatment was carried out throughout a period of several months, both with periodical measurements and sampling and with fixed monitoring probes, in order to record the aquifer changes related to contaminant concentrations, geochemical data, etc. At the end of all the tests we proceeded first with implementation of two phase extraction system through a double line of extraction wells that cover the extension of the area interested by the presence of free phase of LNAPL. The use of this technology instead of other more common system for free product recovery, is due to the fact that two phase extraction system results in an efficient recover of LNAPL and in a low extraction of groundwater that means lower treatment costs. Another important characteristic of this technology is that while extracting oil from the water table it extracts also soil gas from subsoil enhancing hydrocarbons bio-remediation through microbial activity. The second step after the complete recover of free product was to proceed with remediation of subsoil. Bio-remediation processes, enhanced by two phase extraction application, were increased with implementation of a bio-venting system made up of two horizontal wells installed along contaminated area. The injection of air through these wells supply oxygen to subsoil providing necessary aerobic conditions for degradation of hydrocarbon compounds. The results of laboratory tests showed that it would be suitable, to further stimulate microbial activity, to supply micro-nutrient compounds, principally nitrogen and phosphorous. For this reason after a first period

  17. Enhanced Jc property in nano-SiC doped thin MgB 2/Fe wires by a modified in situ PIT process

    Science.gov (United States)

    Jiang, C. H.; Nakane, T.; Hatakeyama, H.; Kumakura, H.

    2005-06-01

    A modified in situ PIT process, which included a short time pre-annealing and intermediate drawing step in the conventional in situ PIT process, was employed to fabricate thin round MgB 2/Fe wires from MgH 2 and B powders. The pores and cracks resulted from the MgH 2 decomposition during the pre-annealing were effectively eliminated by the intermediate drawing step, which subsequently increased the core density and Jc property of final heat treated wires. A higher reduction rate after the pre-annealing led to a larger enhancement in Jc within this study. The reproducibility of our new process on the Jc improvement in MgB 2 wires was confirmed in two series of wires doped with 5 mol% or 10 mol% nano-SiC particles separately.

  18. Enhanced J c property in nano-SiC doped thin MgB2/Fe wires by a modified in situ PIT process

    International Nuclear Information System (INIS)

    A modified in situ PIT process, which included a short time pre-annealing and intermediate drawing step in the conventional in situ PIT process, was employed to fabricate thin round MgB2/Fe wires from MgH2 and B powders. The pores and cracks resulted from the MgH2 decomposition during the pre-annealing were effectively eliminated by the intermediate drawing step, which subsequently increased the core density and J c property of final heat treated wires. A higher reduction rate after the pre-annealing led to a larger enhancement in J c within this study. The reproducibility of our new process on the J c improvement in MgB2 wires was confirmed in two series of wires doped with 5 mol% or 10 mol% nano-SiC particles separately

  19. Comparative studies of atomic layer deposition and plasma-enhanced atomic layer deposition Ta2O5 and the effects on electrical properties of in situ nitridation

    International Nuclear Information System (INIS)

    Ta2O5 and TaOxNy thin films were deposited by atomic layer deposition (ALD) from Ta(NMe2)5 (PDMAT) with water, oxygen plasma, and nitrogen added oxygen plasma. The film properties were comparatively investigated focusing on the electrical properties from metal oxide semiconductor capacitor structure with 10 nm Ta2O5 or TaOxNy. The results show that plasma-enhanced ALD (PE-ALD) Ta2O5 film has better electrical properties including lower interface state density and leakage current than thermal ALD. Moreover, PE-ALD TaOxNy shows the best properties, indicating the beneficial effects of in situ nitridation. Especially, time dependent dielectric breakdown was significantly improved up to 4000 times of thermal ALD Ta2O5. These results show that, intentional in situ nitrogen incorporation with good electrical properties was successfully achieved by PE-ALD using nitrogen-oxygen mixture. (author)

  20. MICROCOSM AND IN-SITU FIELD STUDIES OF ENHANCED BIOTRANSFORMATION OF TRICHLOROETHYLENE BY PHENOL-UTILIZING MICROORGANISMS

    Science.gov (United States)

    The ability of different aerobic groundwater microorganisms to cometabolically degrade trichloroethylene (TCE), 1,2-cis-dichloroethylene (c-DCE), and 1,2-trans-dichloroethylene (t-DCE) was evaluated both in groundwater-fed microcosms and in situ in a shallow aquifer. Microcosms a...

  1. One-week postoperative patency of lower extremity in situ bypass graft comparing epidural and general anesthesia : retrospective study of 822 patients

    DEFF Research Database (Denmark)

    Wiis, Julie Therese; Jensen-Gadegaard, Peter

    2014-01-01

    BACKGROUND: The purpose of this study was to determine whether anesthesia affects graft patency after lower extremity arterial in situ bypass surgery. METHODS: This investigation was a retrospective study using a national database on vascular surgical patients at a single medical institution. We assessed a total of 822 patients exposed to infrainguinal in situ bypass vascular surgery over the period of January 2000 to September 2010. RESULTS: All patients included in the study (age [mean ± SD] 70.8 ± 9.7 years) underwent infrainguinal in situ bypass (n = 885) for lower extremity revascularization under epidural (n = 386) or general (n = 499) anesthesia. Thirty-day mortality (3.4% for epidural anesthesia versus 4.4% general anesthesia; P = 0.414) and comorbidity were comparable in the 2 groups. Graft occlusion within 7 days after surgery was reported in 93 patients, with a similar incidence in the epidural (10.1%) and general (10.8%) anesthesia groups (P = 0.730). When examining a subgroup of patients (n = 242) exposed to surgery on smaller vessels (femorodistal in situ bypass procedures, n = 253), the incidence of graft occlusion was also similar in the 2 groups at 14.0% and 9.4%, respectively (P = 0.262). CONCLUSION: This retrospective study has shown that when graft patency is evaluated 7 days after surgery, anesthetic choice (epidural or general anesthesia) does not influence outcome.

  2. Enhancement of Biodiesel Production from Marine Alga, Scenedesmus sp. through In Situ Transesterification Process Associated with Acidic Catalyst

    OpenAIRE

    Ga Vin Kim; WoonYong Choi; DoHyung Kang; ShinYoung Lee; HyeonYong Lee

    2014-01-01

    The aim of this study was to increase the yield of biodiesel produced by Scenedesmus sp. through in situ transesterification by optimizing various process parameters. Based on the orthogonal matrix analysis for the acidic catalyst, the effects of the factors decreased in the order of reaction temperature (47.5%) > solvent quantity (26.7%) > reaction time (17.5%) > catalyst amount (8.3%). Based on a Taguchi analysis, the effects of the factors decreased in the order of solvent ratio (...

  3. X-231A demonstration of in-situ remediation of DNAPL compounds in low permeability media by soil fracturing with thermally enhanced mass recovery or reactive barrier destruction

    International Nuclear Information System (INIS)

    The overall goal of the program of activities is to demonstrate robust and cost-effective technologies for in situ remediation of DNAPL compounds in low permeability media (LPM), including adaptations and enhancements of conventional technologies to achieve improved performance for DNAPLs in LPM. The technologies sought should be potential for application at simple, small sites (e.g., gasoline underground storage tanks) as well as at complex, larger sites (e.g., DOE land treatment units). The technologies involved in the X-231A demonstration at Portsmouth Gaseous Diffusion Plant (PORTS) utilized subsurface manipulation of the LPM through soil fracturing with thermally enhanced mass recovery or horizontal barrier in place destruction. To enable field evaluation of these approaches, a set of four test cells was established at the X-231A land treatment unit at the DOE PORTS plant in August 1996 and a series of demonstration field activities occurred through December 1997. The principal objectives of the PORTS X-231A demonstration were to: determine and compare the operational features of hydraulic fractures as an enabling technology for steam and hot air enhanced soil vapor extraction and mass recovery, in situ interception and reductive destruction by zero valent iron, and in situ interception and oxidative destruction by potassium permanganate; determine the interaction of the delivered agents with the LPM matrix adjacent to the fracture and within the fractured zone and assess the beneficial modifications to the transport and/or reaction properties of the LPM deposit; and determine the remediation efficiency achieved by each of the technology strategies

  4. X-231A demonstration of in-situ remediation of DNAPL compounds in low permeability media by soil fracturing with thermally enhanced mass recovery or reactive barrier destruction

    Energy Technology Data Exchange (ETDEWEB)

    Siegrist, R.L. [Oak Ridge National Lab., TN (United States)]|[Colorado School of Mines, Golden, CO (United States). Environmental Science and Engineering Div.; Lowe, K.S. [Oak Ridge National Lab., Grand Junction, CO (United States). Life Sciences Div.; Murdoch, L.D. [FRx, Inc., Cincinnati, OH (United States)]|[Clemson Univ., SC (United States); Slack, W.W. [FRx, Inc., Cincinnati, OH (United States); Houk, T.C. [Lockheed Martin Energy Systems, Piketon, OH (United States)

    1998-03-01

    The overall goal of the program of activities is to demonstrate robust and cost-effective technologies for in situ remediation of DNAPL compounds in low permeability media (LPM), including adaptations and enhancements of conventional technologies to achieve improved performance for DNAPLs in LPM. The technologies sought should be potential for application at simple, small sites (e.g., gasoline underground storage tanks) as well as at complex, larger sites (e.g., DOE land treatment units). The technologies involved in the X-231A demonstration at Portsmouth Gaseous Diffusion Plant (PORTS) utilized subsurface manipulation of the LPM through soil fracturing with thermally enhanced mass recovery or horizontal barrier in place destruction. To enable field evaluation of these approaches, a set of four test cells was established at the X-231A land treatment unit at the DOE PORTS plant in August 1996 and a series of demonstration field activities occurred through December 1997. The principal objectives of the PORTS X-231A demonstration were to: determine and compare the operational features of hydraulic fractures as an enabling technology for steam and hot air enhanced soil vapor extraction and mass recovery, in situ interception and reductive destruction by zero valent iron, and in situ interception and oxidative destruction by potassium permanganate; determine the interaction of the delivered agents with the LPM matrix adjacent to the fracture and within the fractured zone and assess the beneficial modifications to the transport and/or reaction properties of the LPM deposit; and determine the remediation efficiency achieved by each of the technology strategies.

  5. In situ Delivery of Antigen to DC-SIGN(+)CD14(+) Dermal Dendritic Cells Results in Enhanced CD8(+) T-Cell Responses.

    Science.gov (United States)

    Fehres, Cynthia M; van Beelen, Astrid J; Bruijns, Sven C M; Ambrosini, Martino; Kalay, Hakan; van Bloois, Louis; Unger, Wendy W J; Garcia-Vallejo, Juan J; Storm, Gert; de Gruijl, Tanja D; van Kooyk, Yvette

    2015-09-01

    CD14(+) dendritic cells (DCs) present in the dermis of human skin represent a large subset of dermal DCs (dDCs) that are considered macrophage-like cells with poor antigen (cross)-presenting capacity and limited migratory potential to the lymph nodes. CD14(+) dDC highly express DC-specific ICAM-3-grabbing non-integrin (DC-SIGN), a receptor containing potent endocytic capacity, facilitating intracellular routing of antigens to major histocompatibility complex I and II (MHC-I andII) loading compartments for the presentation to antigen-specific CD8(+) and CD4(+) T cells. Here we show using a human skin explant model that the in situ targeting of antigens to DC-SIGN using glycan-modified liposomes enhances the antigen-presenting capacity of CD14(+) dDCs. Intradermal vaccination of liposomes modified with the DC-SIGN-targeting glycan Lewis(X), containing melanoma antigens (MART-1 or Gp100), accumulated in CD14(+) dDCs and resulted in enhanced Gp100- or MART-1-specific CD8(+) T-cell responses. Simultaneous intradermal injection of the cytokines GM-CSF and IL-4 as adjuvant enhanced the migration of the skin DCs and increased the expression of DC-SIGN on the CD14(+) and CD1a(+) dDCs. These data demonstrate that human CD14(+) dDCs exhibit potent cross-presenting capacity when targeted in situ through DC-SIGN. PMID:25885805

  6. In situ plasma enhanced atomic layer deposition half cycle study of Al2O3 on AlGaN/GaN high electron mobility transistors

    Science.gov (United States)

    Qin, Xiaoye; Wallace, Robert M.

    2015-08-01

    A half cycle study of plasma enhanced atomic layer deposited (PEALD) Al2O3 on AlGaN is investigated using in situ X-ray photoelectron spectroscopy, low energy ion scattering, and ex situ electrical characterizations. A faster nucleation or growth is detected from PEALD relative to purely thermal ALD using an H2O precursor. The remote O2 plasma oxidizes the AlGaN surface slightly at the initial stage, which passivates the surface and reduces the OFF-state leakage. This work demonstrates that PEALD is a useful strategy for Al2O3 growth on AlGaN/GaN devices.

  7. A surface-enhanced Raman scattering optrode prepared by in situ photoinduced reactions and its application for highly sensitive on-chip detection.

    Science.gov (United States)

    Wang, Shaoyan; Liu, Chunyu; Wang, Hailong; Chen, Gang; Cong, Ming; Song, Wei; Jia, Qiong; Xu, Shuping; Xu, Weiqing

    2014-07-23

    A surface-enhanced Raman scattering (SERS)-active optical fiber sensor combining the optical fiber waveguide with various SERS substrates has been a powerful analytical tool for in situ and long-distance SERS detection with high sensitivity. The design and modification of a high-quality SERS-active sensing layer are important topics in the development of novel SERS-active optical fiber sensors. Here, we prepared a highly sensitive SERS-active optrode by in situ fabrication of a three-dimensional porous structure on the optical fiber end via a photoinduced polymerization reaction, followed by the growth of photochemical silver nanoparticles above the porous polymer material. The fabrication process is rapid (finished within 1 h) and can be on line under light control. The porous structure supports vast silver nanoparticles, which allows for strong electromagnetic enhancement of SERS. Interestingly, the preparation of this SERS optrode and its utilization for SERS detection can all be conducted in a microfluidic chip. The qualitative and quantitative on-chip SERS sensing of organic pollutants and pesticides has been achieved by this SERS optrode-integrated microfluidic chip, and its high detection sensitivity makes it a promising factor in the analysis of liquid systems. PMID:24978908

  8. Enhancement of the sweep efficiency of waterflooding operations by the in-situ microbial population of petroleum reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Brown, L.R.; Vadie, A.A.; Stephens, J.O.; Azadpour, A.

    1995-12-31

    Live cores were obtained from five reservoirs using special precautions to prevent contamination by exogenous microorganisms and minimize exposure to oxygen. The depths from which the cores were obtained ranged from 2,705 ft to 6,568 ft. Core plugs were cut radially from live cores, encased in heat-shrink plastic tubes, placed in core holders, and fitted with inlets and outlets. Nutrient additions stimulated the in-situ microbial population to increase, dissolve stratal material, produce gases, and release oil. Reduction in flow through the core plugs was observed in some cases, while in other cases flow was increased, probably due to the dissolution of carbonates in the formation. A field demonstration of the ability of the in-situ microbial population to increase oil recovery by blocking the more permeable zones of the reservoir is currently underway. This demonstration is being conducted in the North Blowhorn Creek Unit situated in Lamar County, Alabama. Live cores were obtained from a newly drilled well in the field and tested as described above. The field project involves four test patterns each including one injector, four to five producers, and a comparable control injector with its four to five producers. Nutrient injection in the field began November 1994.

  9. In situ loading of well-dispersed silver nanoparticles on nanocrystalline magnesium oxide for real-time monitoring of catalytic reactions by surface enhanced Raman spectroscopy

    Science.gov (United States)

    Zhang, Kaige; Li, Gongke; Hu, Yuling

    2015-10-01

    The surface-enhanced Raman spectroscopy (SERS) technique is of great importance for insight into the transient reaction intermediates and mechanistic pathways involved in heterogeneously catalyzed chemical reactions under actual reaction conditions, especially in water. Herein, we demonstrate a facile method for in situ synthesis of nanocrystalline magnesium oxide-Ag(0) (nano MgO-Ag(0)) hybrid nanomaterials with dispersed Ag nanoparticles (Ag NPs) on the surface of nanocrystalline magnesium oxide (nano MgO) via Sn2+ linkage and reduction. As a benefit from the synergy effect of nano MgO and Ag NPs, the nano MgO-Ag(0) exhibited both excellent SERS and catalytic activities for the reduction of 4-nitrothiophenol in the presence of NaBH4. The nano MgO-Ag(0) was used for real-time monitoring of the catalytic reaction process of 4-nitrothiophenol to 4-aminothiophenol in an aqueous medium by observing the SERS signals of the reactant, intermediate and final products. The intrinsic reaction kinetics and reaction mechanism of this reaction were also investigated. This SERS-based synergy technique provides a novel approach for quantitative in situ monitoring of catalytic chemical reaction processes.The surface-enhanced Raman spectroscopy (SERS) technique is of great importance for insight into the transient reaction intermediates and mechanistic pathways involved in heterogeneously catalyzed chemical reactions under actual reaction conditions, especially in water. Herein, we demonstrate a facile method for in situ synthesis of nanocrystalline magnesium oxide-Ag(0) (nano MgO-Ag(0)) hybrid nanomaterials with dispersed Ag nanoparticles (Ag NPs) on the surface of nanocrystalline magnesium oxide (nano MgO) via Sn2+ linkage and reduction. As a benefit from the synergy effect of nano MgO and Ag NPs, the nano MgO-Ag(0) exhibited both excellent SERS and catalytic activities for the reduction of 4-nitrothiophenol in the presence of NaBH4. The nano MgO-Ag(0) was used for real-time monitoring of the catalytic reaction process of 4-nitrothiophenol to 4-aminothiophenol in an aqueous medium by observing the SERS signals of the reactant, intermediate and final products. The intrinsic reaction kinetics and reaction mechanism of this reaction were also investigated. This SERS-based synergy technique provides a novel approach for quantitative in situ monitoring of catalytic chemical reaction processes. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr05718c

  10. Enhanced electron emission from carbon nanotubes through density control using in situ plasma treatment of catalyst metal

    International Nuclear Information System (INIS)

    We controlled the density of carbon nanotubes (CNTs) through in situ NH3 plasma pretreatment and investigated field emission properties with the density variation. Ni catalytic layer was transformed into small nanoparticles with NH3 plasma pretreatment time and power. As NH3 plasma pretreatment time was increased, the growth rate of grown CNTs was gradually decreased. Also, the density of CNTs reduced from 2x109 to 8x106/cm2 with an increase in NH3 plasma pretreatment time from 10 to 30 min for the Ni layer of 10 Aa. With a decrease in the density of CNTs, the emission current density was increased and turn on electric field was decreased. We obtained large and uniform emission current (about 9 mA/emission area of 0.49 cm2) from CNTs film with the density of 8x106/cm2

  11. Enhanced oral bioavailability of piperine by self-emulsifying drug delivery systems: in vitro, in vivo and in situ intestinal permeability studies.

    Science.gov (United States)

    Shao, Bing; Cui, Chao; Ji, Hongyu; Tang, Jingling; Wang, Zhiyong; Liu, Hongmei; Qin, Mengnan; Li, Xin; Wu, Linhua

    2015-09-01

    The main purpose of this work was to develop and evaluate a self-emulsifying drug delivery system (SEDDS) of piperine to enhance its solubility and bioavailability. The formulation was optimized by solubility test and ternary phase diagrams. Then physiochemical properties and in vitro release of SEDDS were characterized. In vivo pharmacokinetics study and in situ single-pass intestinal perfusion were performed to investigate the effects of SEDDS on the bioavailability and intestinal absorption of piperine. The optimized formulation was composed of ethyl oleate, Tween 80 and Transcutol P (3:5.5:1.5, w/w), with the level of the piperine reached 2.5% (w/w). The in vitro dissolution rates of piperine SEDDS were significantly higher than the self-prepared capsules. In vivo pharmacokinetic study showed Cmax1, Cmax2 and area under the curve of piperine after oral administration of SEDDS in rats were 3.8-, 7.2- and 5.2-fold higher than the self-prepared capsules, respectively, and the relative bioavailability of SEDDS was 625.74%. The in situ intestinal absorption study revealed that the effective permeability and the effective absorption rate values of piperine for SEDDS were significantly improved comparing to solutions (p?

  12. In situ loading of well-dispersed silver nanoparticles on nanocrystalline magnesium oxide for real-time monitoring of catalytic reactions by surface enhanced Raman spectroscopy.

    Science.gov (United States)

    Zhang, Kaige; Li, Gongke; Hu, Yuling

    2015-10-28

    The surface-enhanced Raman spectroscopy (SERS) technique is of great importance for insight into the transient reaction intermediates and mechanistic pathways involved in heterogeneously catalyzed chemical reactions under actual reaction conditions, especially in water. Herein, we demonstrate a facile method for in situ synthesis of nanocrystalline magnesium oxide-Ag(0) (nano MgO-Ag(0)) hybrid nanomaterials with dispersed Ag nanoparticles (Ag NPs) on the surface of nanocrystalline magnesium oxide (nano MgO) via Sn(2+) linkage and reduction. As a benefit from the synergy effect of nano MgO and Ag NPs, the nano MgO-Ag(0) exhibited both excellent SERS and catalytic activities for the reduction of 4-nitrothiophenol in the presence of NaBH4. The nano MgO-Ag(0) was used for real-time monitoring of the catalytic reaction process of 4-nitrothiophenol to 4-aminothiophenol in an aqueous medium by observing the SERS signals of the reactant, intermediate and final products. The intrinsic reaction kinetics and reaction mechanism of this reaction were also investigated. This SERS-based synergy technique provides a novel approach for quantitative in situ monitoring of catalytic chemical reaction processes. PMID:26415789

  13. In situ generation of steam and alkaline surfactant for enhanced oil recovery using an exothermic water reactant (EWR)

    Science.gov (United States)

    Robertson, Eric P

    2011-05-24

    A method for oil recovery whereby an exothermic water reactant (EWR) encapsulated in a water soluble coating is placed in water and pumped into one or more oil wells in contact with an oil bearing formation. After the water carries the EWR to the bottom of the injection well, the water soluble coating dissolves and the EWR reacts with the water to produce heat, an alkali solution, and hydrogen. The heat from the EWR reaction generates steam, which is forced into the oil bearing formation where it condenses and transfers heat to the oil, elevating its temperature and decreasing the viscosity of the oil. The aqueous alkali solution mixes with the oil in the oil bearing formation and forms a surfactant that reduces the interfacial tension between the oil and water. The hydrogen may be used to react with the oil at these elevated temperatures to form lighter molecules, thus upgrading to a certain extent the oil in situ. As a result, the oil can flow more efficiently and easily through the oil bearing formation towards and into one or more production wells.

  14. Usage of waste products from thermal recycling of plastics waste in enhanced oil recovery or in-situ coal conversion

    Energy Technology Data Exchange (ETDEWEB)

    Fink, M.; Fink, J.K. [Montanuniversitaet Leoben (Austria)

    1998-09-01

    In this contribution a thermal method for crude oil mobilization and in-situ liquefaction of coal is discussed, which will finally yield more organic material, as which has been put in from plastics waste originally into the process. The conversion product from thermal treatment is pumped down into exhausted crude oil reservoirs, where the hydrogen can degrade the residual high viscous oil to cause it to become more prone to flow so that it can be recovered. Such a process will envision two goals: 1. more organic raw material (as crude oil) will be recovered than is initially put in as waste product. 2. atmospheric pollutants from the conversion plant will be trapped in the reservoir, which simplifies the construction of the plant. An analogous process may be performed with coal seams. Coal seams with their high porosity and large specific surface are believed to be in particular useful to filter atmospheric pollutants. Depending on the type of coal the mobilization of organic material by this process may be in the background. (orig./SR)

  15. Two-stage in situ gas stripping for enhanced butanol fermentation and energy-saving product recovery

    Energy Technology Data Exchange (ETDEWEB)

    Xue, C; Zhao, JB; Liu, FF; Lu, CC; Yang, ST; Bai, FW

    2013-05-01

    Two-stage gas stripping for butanol recovery from acetone-butanol-ethanol (ABE) fermentation with Clostridium acetobutylicum JB200 in a fibrous bed bioreactor was studied. Compared to fermentation without in situ gas stripping, more ABE (10.0 g/L acetone, 19.2 g/L butanol, 1.7 g/L ethanol vs. 7.9 g/L acetone, 16.2 g/L butanol, 1.4 g/L ethanol) were produced, with a higher butanol yield (0.25 g/g vs. 0.20 g/g) and productivity (0.40 g/L.h vs. 0.30 g/L-h) due to reduced butanol inhibition. The first-stage gas stripping produced a condensate containing 175.6 g/L butanol (227.0 g/L ABE), which after phase separation formed an organic phase containing 612.3 g/L butanol (660.7 g/L ABE) and an aqueous phase containing 101.3 g/L butanol (153.2 g/L ABE). After second-stage gas stripping, a highly concentrated product containing 420.3 g/L butanol (532.3 g/L ABE) was obtained. The process is thus effective in producing high-titer butanol that can be purified with much less energy. (C) 2012 Elsevier Ltd. All rights reserved.

  16. In situ spectroscopic ellipsometry study of TiO2 films deposited by plasma enhanced chemical vapour deposition

    International Nuclear Information System (INIS)

    TiO2 thin films of 300–400 nm were deposited at low pressure (3 mTorr) and temperature (b). The impact of growth interruptions on the film characteristics was studied by in situ spectroscopic ellipsometry (SE), scanning electron microscopy (SEM) and X-ray diffraction. The interruptions were carried out by stopping the plasma generation and gas injection once the increase of the layer thickness during each deposition step was about 100 nm. Suitable ellipsometric models were built to account for the structural and optical differences among the layers grown at different stages. When no bias is applied or Vb = ?10 V, the films deposited with and without interruptions are composed of a dense layer near substrate, an intermediate gradient layer and a top roughness layer. But the growth interruptions result in an increase of the dense layer thickness and a decrease of surface roughness. The discrepancy of the refractive index measured by SE between bottom and upper layers can be reduced by growth interruptions or biasing the substrate. In the case of Vb = ?50 V, the film becomes well organized, the top surface appears smoother, and the refractive index can be increased greatly, without significant effect of growth interruptions.

  17. In situ growth of CdS nanoparticles on UiO-66 metal-organic framework octahedrons for enhanced photocatalytic hydrogen production under visible light irradiation

    Science.gov (United States)

    Zhou, Jian-Jian; Wang, Rong; Liu, Xin-Ling; Peng, Fu-Min; Li, Chuan-Hao; Teng, Fei; Yuan, Yu-Peng

    2015-08-01

    CdS nanoparticles acting as photosensitizer was grown in situ upon UiO-66 metal-organic framework octahedrons through a hydrothermal process. The resultant CdS/UiO-66 hybrid photocatalysts show remarkably active hydrogen evolution under visible light irradiation as compared to CdS and UiO-66 alone. The optimum hybrid with 16 wt% CdS loading shows a hydrogen production rate of 235 ?mol h-1, corresponding to 1.2% quantum efficiency at 420 nm. The improved photocatalytic hydrogen production over hybrid CdS/UiO-66 is ascribed to the efficient interfacial charge transfer from CdS to UiO-66, which effectively suppresses the recombination of photogenerated electron-hole pairs and thereby enhancing the photocatalytic efficiency.

  18. Enhanced visible-light photocatalytic activities of Ag{sub 3}PO{sub 4}/MWCNT nanocomposites fabricated by facile in situ precipitation method

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bo [Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164 (China); Li, Zhongyu, E-mail: zhongyuli@mail.tsinghua.edu.cn [Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164 (China); Changzhou Expansion New Stuff Technology Limited Company, Changzhou 213122 (China); Jilin Institute of Chemical Technology, Jilin 132022 (China); Xu, Song, E-mail: cyanine123@163.com [Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164 (China); Han, Dandan; Lu, Dayong [Jilin Institute of Chemical Technology, Jilin 132022 (China)

    2014-05-01

    Highlights: • Ag{sub 3}PO{sub 4}/MWCNT composites were facilely fabricated via in situ precipitation method. • Ag{sub 3}PO{sub 4}/MWCNT composites exhibited enhanced visible-light photocatalytic activity. • Ag{sub 3}PO{sub 4}/MWCNT composites showed good photostability compared with Ag{sub 3}PO{sub 4} particles. • Possible photocatalytic mechanism under visible-light irradiation was proposed. - Abstract: The Ag{sub 3}PO{sub 4}/MWCNT nanocomposites were facilely fabricated via in situ precipitation method by adding (NH{sub 4}){sub 2}HPO{sub 4} into the mixture of multi-walled carbon nanotube (MWCNT) and AgNO{sub 3} solution under stirring. The as-prepared Ag{sub 3}PO{sub 4}/MWCNT nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), the Brunauer–Emmett–Teller surface area (BET) and UV–vis diffuse reflectance spectroscopy. The TEM results showed that the Ag{sub 3}PO{sub 4} nanoparticles were distributed on the surface of MWCNT uniformly with an average diameter of 70 nm, indicating excellent loading result. The photocatalytic activities of Ag{sub 3}PO{sub 4}/MWCNT nanocomposites were investigated by degrading methylene blue (MB) and malachite green (MG) under visible-light irradiation. It was found that the Ag{sub 3}PO{sub 4}/MWCNT nanocomposite exhibited excellent photocatalytic performance with enhanced photocatalytic efficiency and good photostability compared with bare Ag{sub 3}PO{sub 4}. Furthermore, a possible mechanism for the photocatalytic oxidative degradation was also discussed.

  19. Cavity-Enhanced Gas Analyzer for In-Situ Sampling of Biogenic Gases and Their Isotopes Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project concerns the novel application of cavity-enhanced absorption spectroscopy to quantify biogenic gases (CH4,...

  20. In situ detection of a heat-shock regulatory element binding protein using a soluble synthetic enhancer sequence.

    OpenAIRE

    Harel-Bellan, A.; Brini, A T; Ferris, D K; Robin, P. (ed.); Farrar, W.L.

    1989-01-01

    In various studies, enhancer binding proteins have been successfully absorbed out by competing sequences inserted into plasmids, resulting in the inhibition of the plasmid expression. Theoretically, such a result could be achieved using synthetic enhancer sequences not inserted into plasmids. In this study, a double stranded DNA sequence corresponding to the human heat shock regulatory element was chemically synthesized. By in vitro retardation assays, the synthetic sequence was shown to bind...

  1. Enhanced and sustained topical ocular delivery of cyclosporine A in thermosensitive hyaluronic acid-based in situ forming microgels

    Directory of Open Access Journals (Sweden)

    Wu Y

    2013-09-01

    Full Text Available Yijun Wu, Jing Yao, Jianping Zhou, Fatima Zohra Dahmani State Key Laboratory of Natural Medicines, China Pharmaceutical University, Tongjiaxiang, Nanjing, People’s Republic of China Abstract: For nearly a decade, thermoresponsive ophthalmic in situ gels have been recognized as an interesting and promising ocular topical delivery vehicle for lipophilic drugs. In this study, a series of thermosensitive copolymers, hyaluronic acid-g-poly(N-isopropylacrylamide (HA-g-PNIPAAm, was synthesized, by coupling carboxylic end-capped PNIPAAm to aminated hyaluronic acid through amide bond linkages, and was used as a potential carrier for the topical ocular administration of cyclosporine A (CyA. The lower critical solution temperature of HA-g-PNIPAAm59 in aqueous solutions was measured as 32.7°C, which was not significantly affected by the polymer concentration. Moreover, HA-g-PNIPAAm59 microgels showed a high drug loading efficiency (73.92% and a controlled release profile that are necessary for biomedical application. Transmission electron microscopy (TEM and atomic force microscopy (AFM observations showed that HA-g-PNIPAAm microgels were spherical in shape with homogeneous size. Based on the result of the eye irritation test, the HA-g-PNIPAAm microgels formulation was shown to be safe and nonirritant for rabbit eyes. In addition, HA-g-PNIPAAm microgels achieved significantly higher CyA concentration levels in rabbit corneas (1455.8 ng/g of tissue than both castor oil formulation and commercial CyA eye drops. Therefore, these newly described thermoresponsive HA-g-PNIPAAm microgels demonstrated attractive properties to serve as pharmaceutical delivery vehicles for a variety of ophthalmic applications. Keywords: thermosensitive microgels, ophthalmic drug delivery, hyaluronic acid, cyclosporine A

  2. Origin of springtime ozone enhancements in the lower troposphere over Beijing: in situ measurements and model analysis

    Science.gov (United States)

    Huang, J.; Liu, H.; Crawford, J. H.; Chan, C.; Considine, D. B.; Zhang, Y.; Zheng, X.; Zhao, C.; Thouret, V.; Oltmans, S. J.; Liu, S. C.; Jones, D. B. A.; Steenrod, S. D.; Damon, M. R.

    2014-12-01

    Ozone (O3) concentrations in the lower troposphere (LT) over Beijing have significantly increased over the past two decades as a result of rapid industrialization in China, with important implications for regional air quality and photochemistry of the background troposphere. We characterize the vertical distribution of lower-tropospheric (0-6 km) O3 over Beijing using observations from 16 ozonesonde soundings made during a field campaign in April-May 2005 and MOZAIC (Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft) aircraft measurements over 13 days in the same period. We focus on the origin of LT O3 enhancements observed over Beijing, particularly in May. We use a global 3-D chemistry and transport model (GEOS-Chem CTM) driven by assimilated meteorological fields to examine the transport pathways for O3 pollution, and quantify the sources contributing to O3 and its enhancements in the springtime LT over Beijing. Output from the Global Modeling Initiative (GMI) CTM is also used. High O3 concentrations (up to 94.7 ppbv) were frequently observed at the altitude of ~1.5-2 km. The CTMs captured the timing of the occurrences but significantly underestimated their magnitude. GEOS-Chem simulations and a case study showed that O3 produced in the Asian troposphere (especially from Asian anthropogenic pollution) made major contributions to the observed O3 enhancements. Contributions from anthropogenic pollution in the European and North American troposphere were reduced during these events, in contrast with days without O3 enhancements, when contributions from Europe and North America were substantial. The O3 enhancements typically occurred under southerly wind and warmer conditions. It is suggested that an earlier onset of the Asian summer monsoon would cause more O3 enhancement events in the lower troposphere over the North China Plain in late spring and early summer.

  3. In situ evaluation of orthodontic elastomeric chains

    Scientific Electronic Library Online (English)

    Carolina, Baratieri; Cláudia Trindade, Mattos; Matheus, Alves Jr; Thiago Chon Leon, Lau; Lincoln Issamu, Nojima; Margareth Maria Gomes de, Souza; Monica Tirre, Araujo; Matilde da Cunha Gonçalves, Nojima.

    Full Text Available A hipótese testada foi que a exposição dos elásticos em cadeia ao meio bucal altera sua força de tensão. Portanto, o objetivo deste estudo foi avaliar o comportamento, in situ, de diferentes cadeias elastoméricas quando tensionadas durante 3 semanas. Três tipos de elásticos em cadeia Plastic Chain ( [...] PC), Memory Chain (MC) e Super Slick Chain (SSC) foram inseridos aleatoriamente em 3 dos quadrantes de 13 pacientes com distância fixa de 16 mm e força inicial de 180 g. Foi realizado ensaio de tração em uma máquina de ensaio universal EMIC nos seguintes intervalos: inicial, 1 h, 24 h, 1 semana, 2 semanas e 3 semanas. O teste ANOVA a dois critérios foi aplicado para verificar a influência do material e do tempo na degradação da força. Subsequentemente, foi utilizado o teste ANOVA a um critério e pós-teste de Tukey para identificar diferenças estatísticas (p Abstract in english The hypothesis tested in this study was that intraoral exposure of elastomeric chains alters their tensile strength. For such purpose, it was evaluated the in situ behavior of different elastomeric chains stretched for 3 weeks. Three kinds of elastomeric chains, Plastic chain (PC), Memory chain (MC) [...] and Super slick chain (SSC), were randomly placed in 3 quadrants of 13 patient in a fixed distance of 16 mm and mean initial force of 180 g. Tensile testing was performed in an universal testing machine at different intervals: initial, 1 h, 24 h, 1 week, 2 weeks and 3 weeks. A two-way ANOVA test was performed to identify the influence of both material and time on the force decrease. A subsequent one-way ANOVAtest with the Tukey's post hoc test was used to identify statistically significant intragroup and intergroup remaining force (g and %) differences at 5% significance level. The effect of both the material and the time factors were significant. All groups showed significant force decrease after the 1-h period (23% for PC and 14% for MC and SSC). At the end of the 3-week period, the remaining force was 57% (96 g), 67% (129 g) and 71% (125 g) for PC, MC and SSC, respectively. In conclusion, intraoral exposure of elastomeric chains altered their tensile strength. In general, the greater force decrease occurred within the first hour. The remaining force of the enhanced chains measured at each time interval was greater than the conventional one (PC). After 3 weeks, only the enhanced chains maintained the force applied over 100 g.

  4. Rapidly In Situ Forming Platelet-Rich Plasma Gel Enhances Angiogenic Responses and Augments Early Wound Healing after Open Abdomen

    OpenAIRE

    Bo Zhou; Jianan Ren; Chao Ding; Yin Wu; Dong Hu; Guosheng Gu; Jieshou Li

    2013-01-01

    Objective. The purposes of our present study were to evaluate the potential of platelet-rich plasma gel to enhance granulation tissue formation after open abdomen and to examine whether the effect was attributable to stimulating rapid neovascularization. Methods. Twenty-four rats underwent colon ascendens stent peritonitis surgery to induce sepsis, followed by intraperitoneal injection of nitrogen to create intra-abdominal hypertension. Four hours later, laparotomies were performed. The rats ...

  5. Rational in-situ construction of three-dimensional reduced graphene oxide supported Li2S/C composite as enhanced cathode for rechargeable lithium-sulfur batteries

    Science.gov (United States)

    Wang, D. H.; Xia, X. H.; Xie, D.; Niu, X. Q.; Ge, X.; Gu, C. D.; Wang, X. L.; Tu, J. P.

    2015-12-01

    The construction of advanced cathode materials is indispensable and vital for developing high-performance lithium-sulfur batteries. Herein, we develop a facile in-situ route to synthesize three-dimensional reduced graphene oxide supported Li2S/carbon composite (3D-rGO-Li2S/C). The Li2S/C nanoparticles are intimately anchored on the surface of 3D-rGO forming an integrated 3D porous composite. Due to the improved conductivity and reduced polysulfide dissolution, the 3D-rGO-Li2S/C cathode exhibits enhanced electrochemical performances with a high initial capacity of 819 mAh g-1 at 0.1C, as well as good cycling stability with a capacity retention of 415 mAh g-1 after 100 cycles at 1C. The integrated 3D conductive network is responsible for the enhancement of the electrochemical properties by providing fast ion/electron transfer and high mechanical stability.

  6. Enhanced photoelectrochemical performance of WO{sub 3}/Ti photoanode due to in situ formation of a thin interfacial composite layer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Won Jae, E-mail: wjlee@keri.re.kr [Battery Research Center, Korea Electrotechnology Research Institute (KERI), Changwon 641-120 (Korea, Republic of); Shinde, Pravin S.; Go, Geun Ho; Doh, Chil Hoon [Battery Research Center, Korea Electrotechnology Research Institute (KERI), Changwon 641-120 (Korea, Republic of)

    2013-04-01

    Nanostructured WO{sub 3} thin films were prepared on titanium sheet substrates using a doctor blade technique. X-ray diffraction, Raman and field emission scanning electron microscopy studies revealed that the synthesized WO{sub 3} films are having monoclinic crystal structure, porous, polycrystalline with average grain size of ?50 nm. The photoelectrochemical responses of WO{sub 3} films prepared on treated Ti sheets were recorded in 0.5 M H{sub 2}SO{sub 4} electrolyte under simulated 100 mW/cm{sup 2} illumination. WO{sub 3} film prepared on polished Ti sheet showed considerable enhancement in photocurrent as compared to WO{sub 3} films made on unpolished and pre-oxidized Ti sheets. These results suggest that in situ formation of a thin WO{sub x}–TiO{sub y} interfacial composite layer and improved adhesion of WO{sub 3} nanoparticles owing to increased reactive sites on polished Ti substrate play a significant role in enhancing the photoresponse. Such photoanodes are potential candidates in photoelectrochemical water splitting system for hydrogen generation.

  7. In situ synthesis of porous array films on a filament induced micro-gap electrode pair and their use as resistance-type gas sensors with enhanced performances

    Science.gov (United States)

    Xu, Zongke; Duan, Guotao; Zhang, Hongwen; Wang, Yingying; Xu, Lei; Cai, Weiping

    2015-08-01

    Resistance-type metal-oxide semiconductor gas sensors with high sensitivity and low detection limit have been explored for practical applications. They require both sensing films with high sensitivity to target gases and an appropriate structure of the electrode-equipped substrate to support the sensing films, which is still challenging. In this paper, a new gas sensor of metal-oxide porous array films on a micro-gap electrode pair is designed and implemented by taking ZnO as a model material. First, a micro-gap electrode pair was constructed by sputtering deposition on a filament template, which was used as the sensor's supporting substrate. Then, the sensing film, made up of ZnO porous periodic arrays, was in situ synthesized onto the supporting substrate by a solution-dipping colloidal lithography strategy. The results demonstrated the validity of the strategy, and the as-designed sensor shows a small device-resistance, an enhanced sensing performance with high resolution and an ultralow detection limit. This work provides an alternative method to promote the practical application of resistance-type gas sensors.Resistance-type metal-oxide semiconductor gas sensors with high sensitivity and low detection limit have been explored for practical applications. They require both sensing films with high sensitivity to target gases and an appropriate structure of the electrode-equipped substrate to support the sensing films, which is still challenging. In this paper, a new gas sensor of metal-oxide porous array films on a micro-gap electrode pair is designed and implemented by taking ZnO as a model material. First, a micro-gap electrode pair was constructed by sputtering deposition on a filament template, which was used as the sensor's supporting substrate. Then, the sensing film, made up of ZnO porous periodic arrays, was in situ synthesized onto the supporting substrate by a solution-dipping colloidal lithography strategy. The results demonstrated the validity of the strategy, and the as-designed sensor shows a small device-resistance, an enhanced sensing performance with high resolution and an ultralow detection limit. This work provides an alternative method to promote the practical application of resistance-type gas sensors. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02099a

  8. Enhancement of the thermoelectric performance of ?-Zn4Sb3 by in situ nanostructures and minute Cd-doping

    International Nuclear Information System (INIS)

    ?-Zn4Sb3 compounds doped with minute amounts of Cd were synthesized by the MS-SPS technique, which involves melt spinning (MS) followed by spark plasma sintering (SPS), and the microstructures, thermoelectric and thermodynamic properties were systematically characterized. The non-equilibrium MS-SPS technique generates multi-scale nanostructures in the MS-prepared ribbon-shape samples and the resulting compacted bulk materials. These unique multiple nanostructures result in substantial reductions in lattice thermal conductivities, particularly for samples with a large number of ZnSb nanodots with sizes of 10-30 nm. Meanwhile, Cd-doping remarkably improves the electrical properties of the (Zn1-xCdx)4Sb3 compounds by a slight decrease in electrical conductivity and an apparent enhancement of the Seebeck coefficient. Therefore, the dimensionless figure of merits are significantly improved and the maximum value reaches ?1.30 for the (Zn0.99Cd0.01)4Sb3 sample at 700 K, representing ?13% and ?23% improvements compared with the undoped MS-SPS sample and the 1% Cd-doped melting ingot, respectively. In particular, this value shows no degradation after 10 heat cycles from 300 to 700 K or 30 h annealing at 680 K in vacuum, whereas the ZT of neat sample decreases by ?20% to a relatively low value of ?1.0 after 30 h annealing. The enhanced thermal stability of ZT along with the suppressing effect on the low-temperature ?-? phase transition clearly indicates a large improvement in thermodynamic stability as a result of minute Cd-doping. All the above-mentioned benefits make the minute Cd-doped ?-Zn4Sb3 compound prepared by the MS-SPS technique a promising candidate for mid-range temperature thermoelectric power generation applications.

  9. Trans-resveratrol self-nano-emulsifying drug delivery system (SNEDDS) with enhanced bioavailability potential: optimization, pharmacokinetics and in situ single pass intestinal perfusion (SPIP) studies.

    Science.gov (United States)

    Singh, Gurinder; Pai, Roopa S

    2015-01-01

    Trans-resveratrol (t-RVT) is a potent antioxidant. By virtue of extensive pre-systemic metabolism and existence of enterohepatic recirculation, t-RVT bioavailability is almost zero. The current study aimed to develop self-nanoemulsifying drug delivery systems (SNEDDS) using long-chain triglycerides (LCTs) of t-RVT in an attempt to circumvent such obstacles. Equilibrium solubility studies indicated the choice of Lauroglycol FCC as lipid, and of Labrasol and Transcutol P as surfactants, for formulating the SNEDDS. Ternary phase diagrams were constructed to select the areas of nanoemulsions, and the amounts of lipid (X(1)) and surfactant (X(2)) as the critical factor variables. The SNEDDS were optimized using 3(2) central composite design (CCD) and the optimized formulation (OPT) located using overlay plot. The nanometer size range and high negative values of zeta potential depicted non-coalescent nature of the SNEDDS. Optimized formulation indicated marked improvement in drug release profile vis-à-vis pure drug. Cloud point determination and accelerated stability studies ascertained the stability of OPT. Augmentation in the values of K(a) (3.29-fold) and AUC (4.31-fold) indicated significant enhancement in the rate and extent of bioavailability by the OPT compared with pure drug. In situ perfusion (SPIP) studies in Wistar rats construed remarkable enhancement in the absorptivity and permeability parameters of SNEDDS vis-à-vis the pure drug. Successful establishment of level A of in vitro/in vivo correlation substantiated the judicious choice of the in vitro dissolution milieu for simulating the in vivo conditions. The present study, therefore, reports the successful development of SNEDDS with distinctly enhanced bioavailability of t-RVT. PMID:24512464

  10. In-Situ Generation of Oxide Nanowire Arrays from AgCuZn Alloy Sulfide with Enhanced Electrochemical Oxygen-Evolving Performance.

    Science.gov (United States)

    Xie, Minghao; Ai, Shiqi; Yang, Jian; Yang, Yudi; Chen, Yihan; Jin, Yong

    2015-08-12

    In this study, AgCuZn sulfide is fabricated on the surface of AgCuZn alloys by hydrothermal sulfuration. This ternary metal sulfide is equipped with enhanced activity toward oxygen evolution reaction (OER) in an alkaline electrolyte. Through comparison of the alloys with diverse compositions, we find out the best electrochemical property of a particular alloy sulfide forming on a AgCuZn substrate (Ag:Cu:Zn=43:49:8). The alloy sulfide exhibits an onset overpotential (?) of 0.27 V with a Tafel slope of 95±2 mV dec(-1) and a current density of 130 mA cm(-2) at ? of 0.57 V. Moreover, the obtained AgCuZn sulfide displays excellent stability, where the current density can increase to 130% of the initial value after a water electrolysis test for 100,000 s (27.7 h). Through investigating the electrode before and after the electrocatalysis, we find a remarkable activated process during which self-supported copper-silver oxide nanowire (CuO-Ag2O NW) arrays in situ form on the surface of the electrode. This work provides a feasible strategy for synthesis of high performance nonprecious metal electrocatalysts for water splitting. PMID:26181359

  11. In-situ sonosynthesis of nano N-doped ZnO on wool producing fabric with photo and bio activities, cell viability and enhanced mechanical properties.

    Science.gov (United States)

    Behzadnia, Amir; Montazer, Majid; Rad, Mahnaz Mahmoudi

    2015-08-01

    Here, a simple processing route is introduced for preparation of N-doped nano structure ZnO at 75-80°C using in-situ sonosynthesis method through hydrolysis of zinc acetate at pH?9-10 adjusting with ammonia. Synthesis and fabrication of nano N-doped ZnO were carried out on the wool fabric through impregnation of the fabric in ultrasound bath using different concentrations of zinc acetate followed by curing. The antibacterial and antifungal activities of the treated fabrics were assessed against two common pathogenic bacteria including Escherichia coli, Staphylococcus aureus and the diploid fungus namely Candida albicans. The photo-catalytic activity of nano N-doped ZnO particles on the wool fabric was determined by degradation of Methylene Blue under daylight irradiation. Increasing zinc acetate and prolonged sonication time led to higher photo-catalytic activity as more dye stain degraded from the stained treated fabric under daylight. Higher photo-catalytic activity was observed on the nano N-doped ZnO sonotreated wool fabric having more hydrophilicity. Finally, the treatment indicated no negative effect on the fabric safety while reduced alkaline solubility and yellowness even enhanced the fabric tensile strength. The response surface methodology was also utilized to optimize the wool fabric treatment conditions. PMID:26057020

  12. An innovative bioelectrochemical-anaerobic digestion-coupled system for in-situ ammonia recovery and biogas enhancement: process performance and microbial ecology

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    Ammonia (NH4+/NH3) inhibition during anaerobic digestion process is one of the most frequent problems existing in biogas plants, resulting in unstable process and reduced biogas production. In this study, we developed a novel hybrid system, consisted of a submersed microbial resource recovery cell (SMRC) and a continuous stirred tank reactor (CSTR), to prevent ammonia toxicity during anaerobic digestion by in-situ ammonia recovery and electricity production. In batch experiment, the ammonia concentration in the CSTR decreased from 6 to 0.7 g-N/L with an average recovery rate of 0.18 g-N/L(CSTR)/d. Meanwhile, a maximum power density of 0.71±0.5 W/m2 was produced (10 ?). Both current driven NH4+ migration and free NH3 diffusion were identified as the mechanisms responsible for the ammonia transportation. With an increase in initial ammonia concentration and a decrease in external resistance, the SMRC performance was enhanced. In addition, the coexistence of other cations in CSTR or cathode had no negative effect on the ammonia transportation. In continuous reactor operation, 112% extra biogas production was achieved due to ammonia recovery. High-throughput molecular sequencing analysis showed an impact of ammonia recovery on the microbial community composition in the integrated system. Results clearly indicate the great potential of the SMRC-CSTR-coupled system for efficient and cost-effective ammonia recovery, energy production and treatment of ammonia-rich residues.

  13. NOTE: Characterizing early contrast uptake of ductal carcinoma in situ with high temporal resolution dynamic contrast-enhanced MRI of the breast: a pilot study

    Science.gov (United States)

    Jansen, S. A.; Fan, X.; Medved, M.; Abe, H.; Shimauchi, A.; Yang, C.; Zamora, M.; Foxley, S.; Olopade, O. I.; Karczmar, G. S.; Newstead, G. M.

    2010-10-01

    Improvements in the reliable diagnosis of preinvasive ductal carcinoma in situ (DCIS) by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are needed. In this study, we present a new characterization of early contrast kinetics of DCIS using high temporal resolution (HiT) DCE-MRI and compare it with other breast lesions and normal parenchyma. Forty patients with mammographic calcifications suspicious for DCIS were selected for HiT imaging using T1-weighted DCE-MRI with ~7 s temporal resolution for 90 s post-contrast injection. Pixel-based and whole-lesion kinetic curves were fit to an empirical mathematical model (EMM) and several secondary kinetic parameters derived. Using the EMM parameterized and fitted concentration time curve for subsequent analysis allowed for calculation of kinetic parameters that were less susceptible to fluctuations due to noise. The parameters' initial area under the curve (iAUC) and contrast concentration at 1 min (C1 min) provided the highest diagnostic accuracy in the task of distinguishing pathologically proven DCIS from normal tissue. There was a trend for DCIS lesions with solid architectural pattern to exhibit a negative slope at 1 min (i.e. increased washout rate) compared to those with a cribriform pattern (p < 0.04). This pilot study demonstrates the feasibility of quantitative analysis of early contrast kinetics at high temporal resolution and points to the potential for such an analysis to improve the characterization of DCIS.

  14. Characterizing early contrast uptake of ductal carcinoma in situ with high temporal resolution dynamic contrast-enhanced MRI of the breast: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, S A; Fan, X; Medved, M; Abe, H; Shimauchi, A; Zamora, M; Foxley, S; Karczmar, G S; Newstead, G M [Department of Radiology, University of Chicago, 5841 S. Maryland Ave, MC 2026, Chicago, IL 60637 (United States); Yang, C; Olopade, O I, E-mail: gnewstead@radiology.bsd.uchicago.ed [Department of Medicine, University of Chicago, 5841 S. Maryland Ave, MC 2115, Chicago, IL 60637 (United States)

    2010-10-07

    Improvements in the reliable diagnosis of preinvasive ductal carcinoma in situ (DCIS) by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are needed. In this study, we present a new characterization of early contrast kinetics of DCIS using high temporal resolution (HiT) DCE-MRI and compare it with other breast lesions and normal parenchyma. Forty patients with mammographic calcifications suspicious for DCIS were selected for HiT imaging using T{sub 1}-weighted DCE-MRI with {approx}7 s temporal resolution for 90 s post-contrast injection. Pixel-based and whole-lesion kinetic curves were fit to an empirical mathematical model (EMM) and several secondary kinetic parameters derived. Using the EMM parameterized and fitted concentration time curve for subsequent analysis allowed for calculation of kinetic parameters that were less susceptible to fluctuations due to noise. The parameters' initial area under the curve (iAUC) and contrast concentration at 1 min (C{sub 1min}) provided the highest diagnostic accuracy in the task of distinguishing pathologically proven DCIS from normal tissue. There was a trend for DCIS lesions with solid architectural pattern to exhibit a negative slope at 1 min (i.e. increased washout rate) compared to those with a cribriform pattern (p < 0.04). This pilot study demonstrates the feasibility of quantitative analysis of early contrast kinetics at high temporal resolution and points to the potential for such an analysis to improve the characterization of DCIS. (note)

  15. Characterizing early contrast uptake of ductal carcinoma in situ with high temporal resolution dynamic contrast-enhanced MRI of the breast: a pilot study

    International Nuclear Information System (INIS)

    Improvements in the reliable diagnosis of preinvasive ductal carcinoma in situ (DCIS) by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are needed. In this study, we present a new characterization of early contrast kinetics of DCIS using high temporal resolution (HiT) DCE-MRI and compare it with other breast lesions and normal parenchyma. Forty patients with mammographic calcifications suspicious for DCIS were selected for HiT imaging using T1-weighted DCE-MRI with ?7 s temporal resolution for 90 s post-contrast injection. Pixel-based and whole-lesion kinetic curves were fit to an empirical mathematical model (EMM) and several secondary kinetic parameters derived. Using the EMM parameterized and fitted concentration time curve for subsequent analysis allowed for calculation of kinetic parameters that were less susceptible to fluctuations due to noise. The parameters' initial area under the curve (iAUC) and contrast concentration at 1 min (C1min) provided the highest diagnostic accuracy in the task of distinguishing pathologically proven DCIS from normal tissue. There was a trend for DCIS lesions with solid architectural pattern to exhibit a negative slope at 1 min (i.e. increased washout rate) compared to those with a cribriform pattern (p < 0.04). This pilot study demonstrates the feasibility of quantitative analysis of early contrast kinetics at high temporal resolution and points to the potential for such an analysis to improve the characterization of DCIS. (note)

  16. Cooperative cathode electrode and in situ deposited copper for subsequent enhanced Cd(II) removal and hydrogen evolution in bioelectrochemical systems.

    Science.gov (United States)

    Wang, Qiang; Huang, Liping; Pan, Yuzhen; Zhou, Peng; Quan, Xie; Logan, Bruce E; Chen, Hongbo

    2016-01-01

    Bioelectrochemical systems (BESs) were first operated in microbial fuel cell mode for recovering Cu(II), and then shifted to microbial electrolysis cells for Cd(II) reduction on the same cathodes of titanium sheet (TS), nickel foam (NF) or carbon cloth (CC). Cu(II) reduction was similar to all materials (4.79-4.88mg/Lh) whereas CC exhibited the best Cd(II) reduction (5.86±0.25mg/Lh) and hydrogen evolution (0.35±0.07m(3)/m(3)d), followed by TS (5.27±0.43mg/Lh and 0.15±0.02m(3)/m(3)d) and NF (4.96±0.48mg/Lh and 0.80±0.07m(3)/m(3)d). These values were higher than no copper controls by factors of 2.0 and 5.0 (TS), 4.2 and 2.0 (NF), and 1.8 and 7.0 (CC). These results demonstrated cooperative cathode electrode and in situ deposited copper for subsequent enhanced Cd(II) reduction and hydrogen production in BESs, providing an alternative approach for efficiently remediating Cu(II) and Cd(II) co-contamination with simultaneous hydrogen production. PMID:26528907

  17. In situ synthesis of porous array films on a filament induced micro-gap electrode pair and their use as resistance-type gas sensors with enhanced performances.

    Science.gov (United States)

    Xu, Zongke; Duan, Guotao; Zhang, Hongwen; Wang, Yingying; Xu, Lei; Cai, Weiping

    2015-08-20

    Resistance-type metal-oxide semiconductor gas sensors with high sensitivity and low detection limit have been explored for practical applications. They require both sensing films with high sensitivity to target gases and an appropriate structure of the electrode-equipped substrate to support the sensing films, which is still challenging. In this paper, a new gas sensor of metal-oxide porous array films on a micro-gap electrode pair is designed and implemented by taking ZnO as a model material. First, a micro-gap electrode pair was constructed by sputtering deposition on a filament template, which was used as the sensor's supporting substrate. Then, the sensing film, made up of ZnO porous periodic arrays, was in situ synthesized onto the supporting substrate by a solution-dipping colloidal lithography strategy. The results demonstrated the validity of the strategy, and the as-designed sensor shows a small device-resistance, an enhanced sensing performance with high resolution and an ultralow detection limit. This work provides an alternative method to promote the practical application of resistance-type gas sensors. PMID:26259917

  18. Structure Modification Function of g-C3 N4 for Al2 O3 in the In Situ Hydrothermal Process for Enhanced Photocatalytic Activity.

    Science.gov (United States)

    Li, Fa-tang; Liu, Shao-jia; Xue, Ya-bin; Wang, Xiao-jing; Hao, Ying-juan; Zhao, Jun; Liu, Rui-hong; Zhao, Dishun

    2015-07-01

    Heterojunctions of g-C3 N4 /Al2 O3 (g-C3 N4 =graphitic carbon nitride) are constructed by an in situ one-pot hydrothermal route based on the development of photoactive ?-Al2 O3 semiconductor with a mesoporous structure and a high surface area (188?m(2) g(-1) ) acting as electron acceptor. A structure modification function of g-C3 N4 for Al2 O3 in the hydrothermal process is found, which can be attributed to the coordination between unoccupied orbitals of the Al ions and lone-pair electrons of the N atoms. The as-synthesized heterojunctions exhibit much higher photocatalytic activity than pure g-C3 N4 . The hydrogen generation rate and the reaction rate constant for the degradation of methyl orange over 50?% g-C3 N4 /Al2 O3 under visible-light irradiation (?>420?nm) are 2.5 and 7.3?times, respectively, higher than those over pristine g-C3 N4 . The enhanced activity of the heterojunctions is attributed to their large specific surface areas, their close contact, and the high interfacial areas between the components as well as their excellent adsorption performance, and efficient charge transfer ability. PMID:26043440

  19. Long-term population dynamics and in situ physiology in activated sludge systems with enhanced biological phosphorus removal operated with and without nitrogen removal

    DEFF Research Database (Denmark)

    Lee, N.; Nielsen, P.H.

    2003-01-01

    Quantitative fluorescence in situ hybridization (FISH) and the combination of FISH with microautoradiography (MAR) were used in order to study the long-term population dynamics (2.5 years) and the in situ physiology in two parallel activated sludge pilot systems with enhanced biological phosphorus removal (EBPR). The two systems received the same influent wastewater, but were differently operated (with and without nitrogen removal, respectively). Both systems showed a significant P removal that increased when different substrates (phosphorus (P), acetate and glucose, respectively) were added to the influent wastewater. Rhodocyclus-related bacteria were present in both systems in significant numbers (ranging from 4 to 28%) throughout the whole period. This supports the hypothesis that these bacteria occur in significant numbers in different types of well-operating EBPR activated sludge processes. However, we observed a lower correlation (0.9). The Actinobacteria were the only additional group of bacteria whichshowed a similar degree of correlation to the P content in activated sludge as the Rhodocyclus-related bacteria - but only for the system without nitrogen removal. Significant amounts (less than or equal to12%) of glycogen-accumulating bacteria (GAOs) were detected in the system with nitrogen removal (but not in the other system), but had no, in contrast to previous observations, apparent negative effect on the overall EBPR performance. FISH-MAR indicated that a significant part of the Betaproteobacteria (part of them identified as Rhodocyclus-related bacteria) as well as the Actinobacteria were able to take up P-33(i), [H-3]-acetate and [H-3]-glucose under anaerobic-aerobic conditions. The contribution of anoxic P-33(i) uptake under alternating anaerobic-anoxic conditions was significantly lower. Interestingly, not all Rhodocyclus-related bacteria showed uptake of these three radioactive substrates. This may be due to differences in metabolic state, physiological potential or genotype, not detectable by thepresent probe set for Rhodocyclus-related bacteria. Comparison of the P-33(i), [H-3]-acetate and [H-3]-glucose uptake by activated sludge after different fixation and incubation procedures showed that a part of the observed P-33(i), uptake may have been caused by a combination of a biological and chemical or biologically induced chemical P adsorption.

  20. Enhanced lithium storage in a VO2(B)-multiwall carbon nanotube microsheet composite prepared via an in situ hydrothermal process

    International Nuclear Information System (INIS)

    A novel VO2(B)-multiwall carbon nanotube (MWCNT) composite with a sheet-like morphology was synthesized by a simple in situ hydrothermal process. The morphology and structural properties of the samples were investigated by X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). FE-SEM observations demonstrated that the nanosheets are frequently grown together in the form of bundles composed of numerous nanosheets, each with a smooth surface and a typical length of 300-500 nm, width of 50-150 nm, and thickness of 10-50 nm. Electrochemical measurements were carried out using different discharge cut-off voltages. Electrochemical tests show that the VO2(B)-MWCNT composite cathode features long-term cycling stability and high discharge capacity (177 mAh g-1) in the voltage range of 2.0-3.25 V at 1 C with a capacity retention of 92% after 100 cycles. The electrochemical impedance spectra (EIS) indicate that the VO2(B)-MWCNT composite electrode has very low charge-transfer resistance compared with pure VO2(B), indicating the enhanced ionic conductivity of the VO2(B)-MWCNT composite. The enhanced cycling stability is attributed to the fact that the VO2(B)-MWCNT composite can prevent the aggregation of active materials, accommodate the large volume variation, and maintain good electronic contact. We strongly believe that the VO2(B)-MWCNT composite can be considered as a potential cathode material for lithium-ion batteries.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dingsheng; Gao, Mingxia, E-mail: gaomx@zju.edu.cn; Pan, Hongge; Liu, Yongfeng; Wang, Junhua; Li, Shouquan; Ge, Hongwei

    2014-08-01

    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.

  2. In-situ preparation of N-TiO2/graphene nanocomposite and its enhanced photocatalytic hydrogen production by H2S splitting under solar light

    Science.gov (United States)

    Bhirud, Ashwini P.; Sathaye, Shivaram D.; Waichal, Rupali P.; Ambekar, Jalindar D.; Park, Chan-J.; Kale, Bharat B.

    2015-03-01

    Highly monodispersed nitrogen doped TiO2 nanoparticles were successfully deposited on graphene (N-TiO2/Gr) by a facile in-situ wet chemical method for the first time. N-TiO2/Gr has been further used for photocatalytic hydrogen production using a naturally occurring abundant source of energy i.e. solar light. The N-TiO2/Gr nanocomposite composition was optimized by varying the concentrations of dopant nitrogen and graphene (using various concentrations of graphene) for utmost hydrogen production. The structural, optical and morphological aspects of nanocomposites were studied using XRD, UV-DRS, Raman, XPS, FESEM, and TEM. The structural study of the nanocomposite shows existence of anatase N-TiO2. Further, the details of the components present in the composition were confirmed with Raman and XPS. The morphological study shows that very tiny, 7-10 nm sized, N-TiO2 nanoparticles are deposited on the graphene sheet. The optical study reveals a drastic change in absorption edge and consequent total absorption due to nitrogen doping and presence of graphene. Considering the extended absorption edge to the visible region, these nanocomposites were further used as a photocatalyst to transform hazardous H2S waste into eco-friendly hydrogen using solar light. The N-TiO2/Gr nanocomposite with 2% graphene exhibits enhanced photocatalytic stable hydrogen production i.e. ~5941 ?mol h-1 under solar light irradiation using just 0.2 gm nanocomposite, which is much higher as compared to P25, undoped TiO2 and TiO2/Gr nanocomposite. The enhancement in the photocatalytic activity is attributed to `N' doping as well as high specific surface area and charge carrier ability of graphene. The recycling of the photocatalyst shows a good stability of the nanocomposites. This work may provide new insights to design other semiconductor deposited graphene novel nanocomposites as a visible light active photocatalyst.Highly monodispersed nitrogen doped TiO2 nanoparticles were successfully deposited on graphene (N-TiO2/Gr) by a facile in-situ wet chemical method for the first time. N-TiO2/Gr has been further used for photocatalytic hydrogen production using a naturally occurring abundant source of energy i.e. solar light. The N-TiO2/Gr nanocomposite composition was optimized by varying the concentrations of dopant nitrogen and graphene (using various concentrations of graphene) for utmost hydrogen production. The structural, optical and morphological aspects of nanocomposites were studied using XRD, UV-DRS, Raman, XPS, FESEM, and TEM. The structural study of the nanocomposite shows existence of anatase N-TiO2. Further, the details of the components present in the composition were confirmed with Raman and XPS. The morphological study shows that very tiny, 7-10 nm sized, N-TiO2 nanoparticles are deposited on the graphene sheet. The optical study reveals a drastic change in absorption edge and consequent total absorption due to nitrogen doping and presence of graphene. Considering the extended absorption edge to the visible region, these nanocomposites were further used as a photocatalyst to transform hazardous H2S waste into eco-friendly hydrogen using solar light. The N-TiO2/Gr nanocomposite with 2% graphene exhibits enhanced photocatalytic stable hydrogen production i.e. ~5941 ?mol h-1 under solar light irradiation using just 0.2 gm nanocomposite, which is much higher as compared to P25, undoped TiO2 and TiO2/Gr nanocomposite. The enhancement in the photocatalytic activity is attributed to `N' doping as well as high specific surface area and charge carrier ability of graphene. The recycling of the photocatalyst shows a good stability of the nanocomposites. This work may provide new insights to design other semiconductor deposited graphene novel nanocomposites as a visible light active photocatalyst. Electronic supplementary information (ESI) available: Raman of GO, XPS of GO, FESEM of GO, undoped TiO2 and N-TiO2, graph of % graphene vs. H2 production, hydrogen evolution of recycled T6 sample, XRD of sample (T6) after three cyles of photocatalytic study

  3. Radiologic Findings of Ductal Carcinoma in Situ Arising Within a Juvenile Fibroadenoma: Mammographic, Sonographic and Dynamic Contrast-Enhanced Breast MRI Features

    International Nuclear Information System (INIS)

    Juvenile fibroadenoma is an uncommon histologic variant of fibroadenoma that frequently shows a remarkable and rapid growth. The development of a carcinoma within a fibroadenoma, either in situ or invasive, is a rare condition. We encountered a 36-year-old woman with a palpable mass in the right breast. The radiologic findings were indicative of a fibroadenoma in the breast. Sonographic guided biopsy using a 14G core needle revealed the presence of ductal carcinoma in situ (DCIS) within the juvenile fibroadenoma. Focal excision was performed and the patient underwent radiation therapy in the right breast after surgery

  4. An innovative bioelectrochemical-anaerobic digestion-coupled system for in-situ ammonia recovery and biogas enhancement: process performance and microbial ecology

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2015-01-01

    Ammonia (NH4+/NH3) inhibition during anaerobic digestion process is one of the most frequent problems existing in biogas plants, resulting in unstable process and reduced biogas production. In this study, we developed a novel hybrid system, consisted of a submersed microbial resource recovery cell (SMRC) and a continuous stirred tank reactor (CSTR), to prevent ammonia toxicity during anaerobic digestion by in-situ ammonia recovery and electricity production. In batch experiment, the ammonia conc...

  5. Enhancement of decane-SCR-NOx over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV-vis study.

    Czech Academy of Sciences Publication Activity Database

    Sazama, Petr; ?apek, Libor; Drobná, H.; Sobalík, Zden?k; D?de?ek, Ji?í; Arve, K.; Wichterlová, Blanka

    2005-01-01

    Ro?. 232, ?. 2 (2005), s. 302-317. ISSN 0021-9517 R&D Projects: GA AV ?R 1ET400400413 Grant ostatní: European Union(XX) G5RD2001-00595 Institutional research plan: CEZ:AV0Z40400503 Keywords : SCR-NOx * hydrogen effect * Ag clusters * in situ FTIR Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.780, year: 2005

  6. Surface-Enhanced Raman Scattering (SERS) Surfaces for in-situ trace analysis of PAHs in water by Shifted Excitation Raman Difference Spectroscopy (SERDS)

    OpenAIRE

    Kwon, Yong-Hyok

    2012-01-01

    In-situ monitoring of polycyclic aromatic hydrocarbons (PAHs) in the water body has been of worldwide interest for the last decades because they are known to be toxic to biota even at low concentration in the range of ng/l (ppt). For that purpose, fast response optical sensors based on Raman spectroscopy providing a molecular fingerprint of the analyte are suitable for a rapid identification and quantification of these substances. To achieve the high sensitivity necessary for trace detection ...

  7. Enhancement of electrical characteristics and reliability in crystallized ZrO2 gate dielectrics treated with in-situ atomic layer doping of nitrogen

    Science.gov (United States)

    Huang, Jhih-Jie; Huang, Li-Tien; Tsai, Meng-Chen; Lee, Min-Hung; Chen, Miin-Jang

    2014-06-01

    The crystallized ZrO2 high-K gate dielectrics treated with in-situ atomic layer doping of nitrogen using remote N2 and NH3 plasma were investigated, to suppress the capacitance equivalent thickness (CET), leakage current density (Jg), and interfacial state density (Dit). The stress-induced leakage current (SILC) was reduced significantly as well. The tetragonal/cubic phase of ZrO2 was formed by post metallization annealing at a low temperature of 450 °C to offer a high dielectric constant of the gate oxide. The in-situ atomic layer doping of nitrogen using the remote NH3 plasma contributes to the deactivation of the oxygen vacancies and the well passivation of Dit. Accordingly, a suppressed Jg of 4.79 × 10-5 A cm-2 and Dit of 3.96 × 1011 cm-2 eV-1 were realized in the crystallized ZrO2 gate oxide with a low CET of 1.35 nm. The gate dielectrics were also optically examined by the photoluminescence from the high-K/Si interface, indicating that the Dit is highly correlated with the hydrogen passivation originating from the remote NH3 plasma. The results indicate that in-situ atomic layer doping of nitrogen is an applicable and effective technique to improve the electrical properties of crystallized gate dielectrics in the advanced metal-oxide-semiconductor devices.

  8. Enhancement of electrical characteristics and reliability in crystallized ZrO2 gate dielectrics treated with in-situ atomic layer doping of nitrogen

    International Nuclear Information System (INIS)

    The crystallized ZrO2 high-K gate dielectrics treated with in-situ atomic layer doping of nitrogen using remote N2 and NH3 plasma were investigated, to suppress the capacitance equivalent thickness (CET), leakage current density (Jg), and interfacial state density (Dit). The stress-induced leakage current (SILC) was reduced significantly as well. The tetragonal/cubic phase of ZrO2 was formed by post metallization annealing at a low temperature of 450 °C to offer a high dielectric constant of the gate oxide. The in-situ atomic layer doping of nitrogen using the remote NH3 plasma contributes to the deactivation of the oxygen vacancies and the well passivation of Dit. Accordingly, a suppressed Jg of 4.79 × 10?5 A cm?2 and Dit of 3.96 × 1011 cm?2 eV?1 were realized in the crystallized ZrO2 gate oxide with a low CET of 1.35 nm. The gate dielectrics were also optically examined by the photoluminescence from the high-K/Si interface, indicating that the Dit is highly correlated with the hydrogen passivation originating from the remote NH3 plasma. The results indicate that in-situ atomic layer doping of nitrogen is an applicable and effective technique to improve the electrical properties of crystallized gate dielectrics in the advanced metal-oxide-semiconductor devices.

  9. In-situ remediation strategy for enhanced microbial de-acidification of geogenic sulphuric acid mining lakes - mesocosmic studies; In situ-Sanierungsstrategie zur Foerderung der mikrobiellen Entsaeuerung von geogen schwefelsauren Bergbaurestseen - Mesokosmosstudien

    Energy Technology Data Exchange (ETDEWEB)

    Froemmichen, R.

    2001-07-01

    The author investigated whether neutralisation of acid mining lakes can be enhanced by adding low-cost, complex organic carbon sources. Subjects: Selection of a complex carbon source suited for stimulation of dissimilatory iron and sulfate reduction; design and observation of a near-natural landscape compartment (mesocosmos) at different scales as a preparation for the field study; Description of reactions in the mesocosmic lake water and sediment; Assessment of neutralisation equivalents and neutralisation rates on the basis of an identification of reduced iron and sulphur compounds. [German] Die Hypothese, dass durch Zugabe kostenguenstiger komplexer organischer Kohlenstoffquellen in die sedimentnahe Wasserzone eines sauren Tagebaurestsees seeinterne Neutralisierungsprozesse gefoerdert werden, liegt dieser Arbeit zu Grunde. Seeinterne Neutralisationsprozesse, wie die dissimilatorische Eisen- und Sulfatreduktion, fuehren ueber die Akkumulierung von reduzierten Eisen- und Schwefelverbindungen im Sediment zur Alkalinitaetsbildung im Gewaessersystem und im Seewasser zu hoeheren pH-Werten. Daher leiten sich folgende Ziele fuer diese Arbeit ab: - Auswahl einer geeigneten komplexen Kohlenstoffquelle zur Stimulierung der dissimilatorischen Eisen- und Sulfatreduktion - Design und Beobachtung eines naturnahen Landschaftsausschnittes (Mesokosmos) unterschiedlicher Massstabsebenen in Vorbereitung fuer die Fallstudie im Freiland - Beschreibung von Stoffumsetzungen im Seewasser und -sediment der Mesokosmen - Abschaetzung von Neutralisationsaequivalenten und Bestimmung von Neutralisationsraten anhand der Identifizierung reduzierter Eisen- und Schwefelverbindungen. (orig.)

  10. Enhancement of electrical characteristics and reliability in crystallized ZrO{sub 2} gate dielectrics treated with in-situ atomic layer doping of nitrogen

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Jhih-Jie; Huang, Li-Tien; Tsai, Meng-Chen [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Lee, Min-Hung [Institute of Electro-Optical Science and Technology, National Taiwan Normal University, Taipei 11677, Taiwan (China); Chen, Miin-Jang, E-mail: mjchen@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Center for Emerging Material and Advanced Devices, National Taiwan University, Taipei 10617, Taiwan (China); National Nano Device Laboratories, Hsinchu 30078, Taiwan (China)

    2014-06-01

    The crystallized ZrO{sub 2} high-K gate dielectrics treated with in-situ atomic layer doping of nitrogen using remote N{sub 2} and NH{sub 3} plasma were investigated, to suppress the capacitance equivalent thickness (CET), leakage current density (J{sub g}), and interfacial state density (D{sub it}). The stress-induced leakage current (SILC) was reduced significantly as well. The tetragonal/cubic phase of ZrO{sub 2} was formed by post metallization annealing at a low temperature of 450 °C to offer a high dielectric constant of the gate oxide. The in-situ atomic layer doping of nitrogen using the remote NH{sub 3} plasma contributes to the deactivation of the oxygen vacancies and the well passivation of D{sub it}. Accordingly, a suppressed J{sub g} of 4.79 × 10{sup ?5} A cm{sup ?2} and D{sub it} of 3.96 × 10{sup 11} cm{sup ?2} eV{sup ?1} were realized in the crystallized ZrO{sub 2} gate oxide with a low CET of 1.35 nm. The gate dielectrics were also optically examined by the photoluminescence from the high-K/Si interface, indicating that the D{sub it} is highly correlated with the hydrogen passivation originating from the remote NH{sub 3} plasma. The results indicate that in-situ atomic layer doping of nitrogen is an applicable and effective technique to improve the electrical properties of crystallized gate dielectrics in the advanced metal-oxide-semiconductor devices.

  11. Rapid conversion of the ester prodrug abiraterone acetate results in intestinal supersaturation and enhanced absorption of abiraterone: in vitro, rat in situ and human in vivo studies.

    Science.gov (United States)

    Stappaerts, Jef; Geboers, Sophie; Snoeys, Jan; Brouwers, Joachim; Tack, Jan; Annaert, Pieter; Augustijns, Patrick

    2015-02-01

    The aim of this study was to evaluate the intestinal disposition of abiraterone acetate, an ester prodrug of the anticancer agent abiraterone. Stability of the prodrug and solubility and dissolution characteristics of both abiraterone and abiraterone acetate were monitored in vitro. Moreover, the in vivo intraluminal concentrations of abiraterone and abiraterone acetate upon intake of one tablet of 250 mg abiraterone acetate were assessed in healthy volunteers. The intestinal absorption resulting from the intraluminal behavior of the ester prodrug was determined using the rat in situ intestinal perfusion technique with mesenteric blood sampling. Simulated and aspirated human intestinal fluids of the fasted state were used as solvent systems. Upon incubation of abiraterone acetate in human intestinal fluids in vitro, rapid hydrolysis of the prodrug was observed, generating abiraterone concentrations largely exceeding the apparent solubility of abiraterone, suggesting the existence of intestinal supersaturation. These findings were confirmed in vivo, by intraluminal sampling of duodenal fluids upon oral intake of an abiraterone acetate tablet by healthy volunteers. Rat in situ intestinal perfusion experiments performed with suspensions of abiraterone and abiraterone acetate in human intestinal fluids of the fasted state revealed significantly higher flux values upon perfusion with the prodrug than with abiraterone. Moreover, rat in situ intestinal perfusion with abiraterone acetate suspensions in simulated fluids of the fasted state in presence or absence of esterases demonstrated that increased hydrolytic activity of the perfusion medium was beneficial to the intestinal absorption of abiraterone. In conclusion, the rapid hydrolysis of abiraterone acetate in the intraluminal environment appears to result in fast and extensive generation of abiraterone supersaturation, creating a strong driving force for abiraterone absorption. PMID:25592324

  12. Design and implementation of two two-week Teacher Enhancement Institutes

    Science.gov (United States)

    Lambert, Lynn

    1994-01-01

    During this summer, I have been part of a four team effort that planned and executed two two-week Teacher Enhancement Institutes (TEI) for 40 K-8 teachers from this area. The TEI was designed to enhance teachers' background in aeronautics and technology so that they would be better equipped to encourage and to train students in the mathematics, science, and technology fields. The teachers were given a stipend and three graduate credits from Christopher Newport University for their participation in this program. The four ASEE fellows worked together to develop objectives and a schedule of activities for each two-week session based on the program outline given in the grants that were funding this effort. We divided the responsibilities in coordinating and implementing each part of the TEI based on the specific strengths and background of each ASEE fellow. My specific responsibilities were: (1) to develop the course syllabus and generally handle all matters involved with the graduate course; (2) coordinate the follow-up sessions; and (3) design and manage half of the technology sessions that we had scheduled (approximately 30% of the TEI was devoted to technology). Because the first two responsibilities were primarily administrative in nature, I will address only the last. The technology sessions were divided into computer-only and other technologies (e.g., television and digital technology including scanning, digital photography and CD-ROM). I had responsibility for the computer-only technology sessions. The emphasis of these sessions was on use of the Internet specifically to locate and use educational resources. To maximize learning, these sessions were hands-on with two teachers at each computer. Each teacher received instruction in, and actually used, the most popular tools available on the Internet: email (they were given temporary accounts at NASA LaRC), anonymous ftp and archie, gopher and veronica, mosaic, and telnet. Teachers participated in hands-on workshops to learn about these programs, but were also given time during the two-week session to explore on their own and to find resources on the Net that specifically met their needs. In order to ensure that Internet access continues after their return to the classroom, aIl teachers who did not have them also applied for Learning Link accounts (from WHRO, the local public television station) and Virginia Pen accounts (from the Department of Education of Virginia), both of which allow textbased access to Internet. In addition to getting exposure to and practice with Internet tools, teachers were aIso given a hands-on seminar (and also given practice time) on ClarisWorks, an integrated word processing, spreadsheet, database, and paint package. The technology sessions (and TEI as a whole) were enthusiastically received by both new and more experienced teachers as extremely helpful in improving their ability to use technology in developing lesson pIans.

  13. In situ groundwater bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Terry C.

    2009-02-01

    In situ groundwater bioremediation of hydrocarbons has been used for more than 40 years. Most strategies involve biostimulation; however, recently bioaugmentation have been used for dehalorespiration. Aquifer and contaminant profiles are critical to determining the feasibility and strategy for in situ groundwater bioremediation. Hydraulic conductivity and redox conditions, including concentrations of terminal electron acceptors are critical to determine the feasibility and strategy for potential bioremediation applications. Conceptual models followed by characterization and subsequent numerical models are critical for efficient and cost effective bioremediation. Critical research needs in this area include better modeling and integration of remediation strategies with natural attenuation.

  14. Polyaniline-decorated {001} facets of Bi2O2CO3 nanosheets: in situ oxygen vacancy formation and enhanced visible light photocatalytic activity.

    Science.gov (United States)

    Zhao, Ziyan; Zhou, Ying; Wang, Fang; Zhang, Kunhao; Yu, Shan; Cao, Kun

    2015-01-14

    Polyaniline (PANI)-decorated {001} facets of Bi2O2CO3 nanosheets were synthesized by a low-temperature chemical method. We demonstrate that the strong interfacial interactions between Bi2O2CO3 {001} facets and PANI could promote in situ formation of oxygen vacancy at the interface confirmed by both density functional theory calculations and electron spin resonance experiments, which is due to the high oxygen density characteristic of Bi2O2CO3 {001} facets. In addition, such interfacial interaction also leads to a 0.38 eV positive shifting of the valence band of Bi2O2CO3. Importantly, the decorated PANI can stabilize these interfacial oxygen vacancies. Therefore, the migration and separation of photogenerated carriers have been improved significantly evidenced by electrochemical impedance spectroscopy, photoluminescence, and nanosecond time-resolved fluorescence-decay spectra, resulting in a 4.5 times higher activity toward photodegradation of Rhodamine B and a 6 times higher photocurrent density compared to their corresponding bare Bi2O2CO3. The finding of the in situ oxygen vacancy formation at the interface could provide some hints for the deep understanding of the interactions between PANI and crystal facets of semiconductors to develop highly efficient photocatalysts. PMID:25495565

  15. Poly(lactic acid)-Based in Situ Microfibrillar Composites with Enhanced Crystallization Kinetics, Mechanical Properties, Rheological Behavior, and Foaming Ability.

    Science.gov (United States)

    Kakroodi, Adel Ramezani; Kazemi, Yasamin; Ding, WeiDan; Ameli, Aboutaleb; Park, Chul B

    2015-12-14

    Melt blending is one of the most promising techniques for eliminating poly(lactic acid)'s (PLA) numerous drawbacks. However, success in a typical melt blending process is usually achieved through the inclusion of high concentrations of a second polymeric phase which can compromise PLA's green nature. In a pioneering study, we introduce the production of in situ microfibrillar PLA/polyamide-6 (PA6) blends as a cost-effective and efficient technique for improving PLA's properties while minimizing the required PA6 content. Predominantly biobased products, with only 3 wt % of in situ generated PA6 microfibrils (diameter ?200 nm), were shown to have dramatically improved crystallization kinetics, mechanical properties, melt elasticity and strength, and foaming-ability compared with PLA. Crucially, the microfibrillar blends were produced using an environmentally friendly and cost-effective process. Both of these qualities are essential in guarantying the viability of the proposed technique for overcoming the obstacles associated with the vast commercialization of PLA. PMID:26536276

  16. Uranium in situ leaching

    International Nuclear Information System (INIS)

    Despite the depressed situation that has affected the uranium industry during the past years, the second Technical Committee Meeting on Uranium In Situ Leaching, organized by the International Atomic Energy Agency and held in Vienna from 5 to 8 October 1992, has attracted a relatively large number of participants. A notable development since the first meeting was that the majority of the contributions came from the actual operators of in situ leaching uranium production. At the present meeting, presentations on operations in the USA were balanced by those of the eastern European and Asian countries. Contributions from Bulgaria, China, Czechoslovakia, Germany (from the operation in the former German Democratic Republic), the Russian Federation and Uzbekistan represent new information not commonly available. In situ leach mining is defined in one of the paper presented as a ''mining method where the ore mineral is preferentially leached from the host rock in place, or in situ, by the use of leach solutions, and the mineral value is recovered. Refs, figs and tabs

  17. Performance enhancements and muscular adaptations of a 16-week recreational football intervention for untrained women.

    Science.gov (United States)

    Bangsbo, J; Nielsen, J J; Mohr, M; Randers, M B; Krustrup, B R; Brito, J; Nybo, L; Krustrup, P

    2010-04-01

    The present study investigated the performance effects and physiological adaptations over 16 weeks of recreational football training and continuous running for healthy untrained premenopausal women in comparison with an inactive control group [Football group (FG): n=21; running group (RG): n=18; CO: n=14]. Two weekly 1-h training sessions were performed in FG and RG. After 4 and 16 weeks of training VO(2max) was elevated (Pwomen's football leads to significant increases in VO(2max), performance and muscular adaptations throughout a 16-week training period. Thus, football can be used as an activity to elevate the physical capacity of untrained women. PMID:19954496

  18. Performance enhancements and muscular adaptations of a 16-week recreational football intervention for untrained women

    DEFF Research Database (Denmark)

    Bangsbo, Jens; Nielsen, Jens Jung

    2010-01-01

    The present study investigated the performance effects and physiological adaptations over 16 weeks of recreational football training and continuous running for healthy untrained premenopausal women in comparison with an inactive control group [Football group (FG): n=21; running group (RG): n=18; CO: n=14]. Two weekly 1-h training sessions were performed in FG and RG. After 4 and 16 weeks of training VO(2max) was elevated (P<0.05) by 7% and 15%, respectively, in FG, and by 6% and 10%, respectively, in RG. After 16 weeks, Yo-Yo intermittent endurance level 2 performance was 33% and 19% better (P<0.05) for FG and 29% and 21% better (P<0.05) for RG than after 4 and 0 weeks, respectively. Peak sprinting speed was 12% higher (21.0 +/- 0.6 vs 18.8 +/- 0.7 km/h; P<0.05) for FG after the training period, whereas no difference was observed for RG. After 4 weeks citrate synthase (CS) and 3-hydroxyacyl-CoA dehydrogenase (HAD) activity was 9% and 8%, respectively, higher (P<0.05) than before training in FG with no further changes during the last 12 weeks. In RG, CS increased (P<0.05) by 12% after 4 weeks and no significant increase was observed for HAD. In FG, the number of capillaries per fiber was 18% higher (P<0.05) after 16 weeks (2.44 +/- 0.15 vs 2.07 +/- 0.05 cap/fiber), with no significant difference for RG. No differences were observed between 0 and 16 weeks for CO. In conclusion, recreational women's football leads to significant increases in VO(2max), performance and muscular adaptations throughout a 16-week training period. Thus, football can be used as an activity to elevate the physical capacity of untrained women.

  19. The enhanced Jc and Birr of in situ MgB2 wires and tapes alloyed with C4H6O5 (malic acid) after cold high pressure densification

    International Nuclear Information System (INIS)

    Cold high pressure densification, a method recently introduced at GAP in Geneva, was applied for improving the transport critical current density, Jc, and the irreversibility field, Birr, of monofilamentary in situ MgB2 wires and tapes alloyed with 10 wt% C4H6O5 (malic acid). Tapes densified at 1.48 GPa exhibited after reaction an enhancement of Jc from 2 to 4 x 104 A cm-2 at 4.2 K/10 T and from 0.5 to 4 x 104 A cm-2 at 20 K/5 T, while the Birr was enhanced from 19.3 to 22 T at 4.2 K and from 7.5 to 10.0 T at 20 K. Cold densification also caused a strong enhancement of B(104), the field at which Jc takes the value 1 x 104 A cm-2. For tapes subjected to 1.48 GPa, B(104)|| and B(104)perpendicular at 4.2 K were found to increase from 11.8 and 10.5 T to 13.2 and 12.2 T, respectively. Almost isotropic conditions were obtained for rectangular wires with aspect ratios a/b4)||=12.7 and B(104)perpendicular=12.5 T were obtained. At 20 K, the wires exhibited an almost isotropic behavior, with B(104)||=5.9 T and B(104)perpendicular=5.75 T, Birr(20 K) being ?10 T. These values are equal to or higher than the highest values reported so far for isotropic in situ wires with SiC or other carbon based additives. Further improvements are expected on optimizing the cold high pressure densification process, which has the potential for fabrication of MgB2 wires of industrial lengths.

  20. In Situ Mass Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The In Situ Mass Spectrometer projects focuses on a specific subsystem to leverage advanced research for laser-based in situ mass spectrometer development...

  1. Two weeks of metformin treatment induces AMPK dependent enhancement of insulin-stimulated glucose uptake in mouse soleus muscle

    DEFF Research Database (Denmark)

    Kristensen, Jonas Møller; Treebak, Jonas Thue; Schjerling, Peter; Goodyear, Laurie; Wojtaszewski, Jorgen F P; Wojtaszewski, Jørgen

    2014-01-01

    Background: Metformin-induced activation of AMPK has been associated with enhanced glucose uptake in skeletal muscle but so far no direct causality has been examined. We hypothesized that an effect of in vivo metformin treatment on glucose uptake in mouse skeletal muscles is dependent upon AMPK signaling. Methods: Oral doses of metformin or saline treatment were given muscle-specific kinase ?2 dead AMPK mice (KD) and wild type (WT) littermates either once or chronically for 2 weeks. Soleus and E...

  2. In situ synthesis of hierarchical flower-like Bi2S3/BiOCl composite with enhanced visible light photocatalytic activity

    International Nuclear Information System (INIS)

    Novel BiOCl micro-flower was synthesized by a facile method and used as a precursor to produce Bi2S3/BiOCl composites. The Bi2S3/BiOCl composites, synthesized by in situ etching of BiOCl precursor with thiacetamide (TAA) solution, maintain the hierarchical flower-like structure and exhibit a large surface area. X-ray diffraction (XRD), Fourier transform infrared spectrometry (FT-IR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), and UV–vis diffuse reflectance spectroscopy (DRS) were employed to study the structures, morphologies and optical properties of the as-prepared samples. Under visible light (? > 400 nm), the flower-like Bi2S3/BiOCl composite displayed much higher photocatalytic activity than single Bi2S3, BiOCl and 2D plate-like Bi2S3/BiOCl composite for the degradation of rhodamine B (RhB). The increased photocatalytic activity of Bi2S3/BiOCl could be attributed to the formation of the heterostructure between Bi2S3 and BiOCl and large surface area of the hierarchical structure, which effectively separate the photoinduced electron–hole pairs and suppress their recombination.

  3. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-component DNAPLS with surfactant solutions. Topical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Laboratory studies were conducted at the State University of New York at Buffalo (SUNY) while numerical simulation and field work were undertaken by INTERA Inc. in collaboration with Martin Marietta Energy Systems Inc. at the Paducah Gaseous Diffusion Plant (PGDP) in Kentucky. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). Ten of these were capable of solubilizing TCE to concentrations greater than 15,000 mg/L, compared to its aqueous solubility of 1,100 mg/L. Four surfactants were identified as good solubilizers of all three chlorinated solvents. Of these, a secondary alcohol ethoxylate was the first choice for in situ testing because of its excellent solubilizing ability and its low propensity to sorb. However, this surfactant did not meet the Commonwealth of Kentucky`s acceptance criteria. Consequently, it was decided to use a surfactant approved for use by the Food and Drug Administration as a food-grade additive. As a 1% micellar-surfactant solution, this sorbitan monooleate has a solubilization capacity of 16,000 mg TCE/L, but has a higher propensity to sorb to clays than has the alcohol ethoxylate.

  4. Determination of HER-2 status on FNAC material from breast carcinomas using in situ hybridization with dual chromogen visualization with silver enhancement (dual SISH

    Directory of Open Access Journals (Sweden)

    Beraki Elsa

    2010-01-01

    Full Text Available During the last years, HER-2 status kits and protocols for chromogen visualization of hybridization signals have come on the market. The first generation using chromogen visualization used single color probes. The second generation, now emerging on the market, uses dual chromogen visualization. The aim of this study has been to test a new dual color chromogen kit (Ventana INFORM HER2 Dual Colour ISH Roche ® and compare the results with our in-house method(s. The material consisted primarily of cytological material from invasive breast carcinomas in 49 women. Dual SISH was done on all 49 cytological and histological specimens. The histological specimens were treated according to the manufacturer?s recommendations. The procedure was modified in several steps in order to adapt it to the cytological material. Hybridization failed in two cytological specimens. Dual SISH showed concordant results on cytological and histological material as to amplified/not amplified. The included cases had the same HER-2 expression in the invasive and the in situ components on histology. Four IDC showed HER-2 amplification (8.5%. Polysomy was found in two cases. All dual SISH results except for one concurred with the results of the in-house method(s (1/47=2.1%. The dual SISH is suitable for cytological examination of HER-2 status. The protocol must be optimized for cytological material.

  5. In situ synthesis of hierarchical flower-like Bi{sub 2}S{sub 3}/BiOCl composite with enhanced visible light photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Saihua [State Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui 230026 (China); Department of Civil and Architectural Engineering, City University of Hong Kong and USTC-CityU Joint Advanced Research Centre, Suzhou (China); Zhou, Keqing [State Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui 230026 (China); Shi, Yongqian [State Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui 230026 (China); Department of Civil and Architectural Engineering, City University of Hong Kong and USTC-CityU Joint Advanced Research Centre, Suzhou (China); Lo, Siuming [Department of Civil and Architectural Engineering, City University of Hong Kong and USTC-CityU Joint Advanced Research Centre, Suzhou (China); Xu, Haiyan [Nano Science and Technology Institute, University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui 230027 (China); Hu, Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui 230026 (China); Gui, Zhou, E-mail: zgui@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui 230026 (China)

    2014-01-30

    Novel BiOCl micro-flower was synthesized by a facile method and used as a precursor to produce Bi{sub 2}S{sub 3}/BiOCl composites. The Bi{sub 2}S{sub 3}/BiOCl composites, synthesized by in situ etching of BiOCl precursor with thiacetamide (TAA) solution, maintain the hierarchical flower-like structure and exhibit a large surface area. X-ray diffraction (XRD), Fourier transform infrared spectrometry (FT-IR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), and UV–vis diffuse reflectance spectroscopy (DRS) were employed to study the structures, morphologies and optical properties of the as-prepared samples. Under visible light (? > 400 nm), the flower-like Bi{sub 2}S{sub 3}/BiOCl composite displayed much higher photocatalytic activity than single Bi{sub 2}S{sub 3}, BiOCl and 2D plate-like Bi{sub 2}S{sub 3}/BiOCl composite for the degradation of rhodamine B (RhB). The increased photocatalytic activity of Bi{sub 2}S{sub 3}/BiOCl could be attributed to the formation of the heterostructure between Bi{sub 2}S{sub 3} and BiOCl and large surface area of the hierarchical structure, which effectively separate the photoinduced electron–hole pairs and suppress their recombination.

  6. Time-resolved in situ detection of CO in a shock tube using cavity-enhanced absorption spectroscopy with a quantum-cascade laser near 4.6 µm.

    Science.gov (United States)

    Sun, Kai; Wang, Shengkai; Sur, Ritobrata; Chao, Xing; Jeffries, Jay B; Hanson, Ronald K

    2014-10-01

    Cavity-enhanced absorption spectroscopy (CEAS) using a mid-infrared DFB quantum-cascade laser is reported for sensitive time-resolved (10 ?s) in situ CO measurements in a shock tube. Off-axis alignment and fast scanning of the laser wavelength were used to minimize coupling noise in a low-finesse cavity. An absorption gain factor of 91 was demonstrated, which enabled sub-ppm detection sensitivity for gas temperatures of 1000-2100K in a 15 cm diameter shock tube. This substantial improvement in detection sensitivity compared to conventional single-pass absorption measurements, shows great potential for the study of reaction pathways of high-temperature combustion kinetics mechanisms in shock tubes. PMID:25322031

  7. Gold Nano-Popcorn Based Targeted Diagonosis, Nanotherapy Treatment and In-Situ Monitoring of Photothermal Therapy Response of Prostate Cancer Cells Using Surface Enhanced Raman Spectroscopy

    OpenAIRE

    Lu, Wentong; Singh, Anant Kumar; Khan, Sadia Afrin; Senapati, Dulal; Yu, Hongtao; Ray, Paresh Chandra

    2010-01-01

    Prostate cancer is the second leading cause of cancer-related death among the American male population and the cost of treating prostate cancer patients is about $10 billion/year in the US. Current treatments are mostly ineffective against advanced stage prostate cancer disease and are often associated with severe side effects. Driven by the need, in this manuscript, we report multifunctional nanotechnology-driven gold nano-popcorn based surface enhanced Raman scattering (SERS) assay for targ...

  8. Differentiation of acute and four-week old myocardial infarct with Gd(ABE-DTTA-enhanced CMR

    Directory of Open Access Journals (Sweden)

    Ruzsics Balazs

    2010-04-01

    Full Text Available Abstract Background Standard extracellular cardiovascular magnetic resonance (CMR contrast agents (CA do not provide differentiation between acute and older myocardial infarcts (MI. The purpose of this study was to develop a method for differentiation between acute and older myocardial infarct using myocardial late-enhancement (LE CMR by a new, low molecular weight contrast agent. Dogs (n = 6 were studied in a closed-chest, reperfused, double myocardial infarct model. Myocardial infarcts were generated by occluding the Left Anterior Descending (LAD coronary artery with an angioplasty balloon for 180 min, and four weeks later occluding the Left Circumflex (LCx coronary artery for 180 min. LE images were obtained on day 3 and day 4 after second myocardial infarct, using Gd(DTPA (standard extracellular contrast agent and Gd(ABE-DTTA (new, low molecular weight contrast agent, respectively. Triphenyltetrazolium chloride (TTC histomorphometry validated existence and location of infarcts. Hematoxylin-eosin and Masson's trichrome staining provided histologic evaluation of infarcts. Results Gd(ABE-DTTA or Gd(DTPA highlighted the acute infarct, whereas the four-week old infarct was visualized by Gd(DTPA, but not by Gd(ABE-DTTA. With Gd(ABE-DTTA, the mean ± SD signal intensity enhancement (SIE was 366 ± 166% and 24 ± 59% in the acute infarct and the four-week old infarct, respectively (P Conclusions Late enhancement CMR with separate administrations of standard extracellular contrast agent, Gd(DTPA, and the new low molecular weight contrast agent, Gd(ABE-DTTA, differentiates between acute and late subacute infarct in a reperfused, double infarct, canine model.

  9. In Situ Aerosol Detector Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is developing new platform systems that have the potential to benefit Earth science research activities, which include in situ instruments for atmospheric...

  10. Enhanced methanol electro-oxidation over in-situ carbon and graphene supported one dimensional NiMoO4 nanorods

    Science.gov (United States)

    Jothi, Palani Raja; Kannan, Shanthi; Velayutham, G.

    2015-03-01

    Non-precious NiMoO4 nanorods with carbon and graphene have been designed for methanol oxidation via one pot hydrothermal method. The physicochemical and electrocatalytic features of these catalysts are characterized. Among the three catalysts, carbon modified NiMoO4 shows an enhanced catalytic activity in terms of current density, onset potential, cyclic stability and high tolerance to intermediate towards methanol electro-oxidation. Moreover, the NiMoO4/C catalyst delivers a current density of 49 mA cm-2 at low onset potential of 0.45 V (vs. Hg/HgO) in 1 M KOH and 2.0 M methanol electrolyte. This greater electrocatalytic activity is attributed to the unique 1D microstructure of NiMoO4 nanorods with well distributed carbonaceous material, which enhances the efficient transport of electron/ion kinetics at the electrode and electrolyte interfaces. From this observation, it is concluded that the carbon modified NiMoO4 nanorods could be a promising alternate non-noble electrocatalysts for direct methanol fuel cell (DMFC) applications.

  11. Two weeks of metformin treatment induces AMPK dependent enhancement of insulin-stimulated glucose uptake in mouse soleus muscle

    DEFF Research Database (Denmark)

    Kristensen, Jonas MØller; Treebak, Jonas Thue

    2014-01-01

    Background: Metformin-induced activation of AMPK has been associated with enhanced glucose uptake in skeletal muscle but so far no direct causality has been examined. We hypothesized that an effect of in vivo metformin treatment on glucose uptake in mouse skeletal muscles is dependent upon AMPK signaling. Methods: Oral doses of metformin or saline treatment were given muscle-specific kinase ?2 dead AMPK mice (KD) and wild type (WT) littermates either once or chronically for 2 weeks. Soleus and Extensor Digitorum Longus (EDL) muscles were used for measurements of glucose transport and Western blot analyzes. Results: Chronic treatment with metformin enhanced insulin-stimulated glucose uptake in soleus muscles of WT (45%, P

  12. In situ spectroelectrochemical surface-enhanced Raman scattering (SERS) investigations on composite Ag/TiO 2-nanotubes/Ti substrates

    Science.gov (United States)

    Roguska, A.; Kudelski, A.; Pisarek, M.; Lewandowska, M.; Kurzyd?owski, K. J.; Janik-Czachor, M.

    2009-09-01

    A tubular array of TiO 2-nanotubes on a Ti substrate was used as a support for an Ag sputter-deposited layer intended for surface-enhanced Raman scattering (SERS) investigations. Composite samples of Ag/TiO 2-nanotube/Ti were studied with the aid of scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) to reveal their characteristic morphological and chemical features. Raman spectra of pyridine (as a probe molecule) were measured at different cathodic potentials ranging from -0.2 down to -1.2 V after the pyridine had been adsorbed on the TiO 2-nanotube/Ti substrates covered with the Ag deposit. In addition, SERS spectra on a bulk electrochemically-roughened Ag reference substrate, were also measured. The SERS activity of the composite samples was strongly dependent on the amount of Ag deposit and, in some cases, was even higher than that for the Ag reference substrate. The SERS intensity vs. electrode potential dependences measured were interpreted in terms of the modified electronic structure of the Ag deposits due to the interaction of the Ag clusters with the TiO 2-nanotube/Ti substrate.

  13. Modelling of carbon transport in fusion devices: evidence of enhanced re-erosion of in-situ re-deposited carbon

    International Nuclear Information System (INIS)

    The paper presents new Monte-Carlo transport simulations of methane 13CH4 injected through a hole in a testlimiter and exposed to the edge plasma of TEXTOR. The results show that the spatial distribution of 13C re-deposited locally on the testlimiter surface can be modelled if the parameter S for the sticking of returning hydrocarbons 13CHy is set to zero or almost zero. This is interpreted as a negligible effective sticking of the returning hydrocarbon radicals due to the instantaneous re-erosion caused by the hydrogen carried with the CHy radicals ('self re-erosion'). However, the calculated local deposition efficiency of 13C, remains too high compared with the observed value. Therefore, in addition an enhanced yield for chemical erosion caused by the background hydrogen for the fresh re-deposits has to be assumed. Similar assumptions can reproduce also the high amount of carbon deposition found on the inner louvers in the MkIIa divertor configuration of JET and on the plasma-shadowed areas of the MkIIGB divertor

  14. Large upper tropospheric ozone enhancements above mid-latitude North America during summer: In situ evidence from the IONS and MOZAIC ozone monitoring network

    Science.gov (United States)

    Cooper, O.; Stohl, A.; Trainer, M.; Thompson, A.; Witte, J.; Oltmans, S.; Johnson, B.; Merrill, J.; Moody, J.; Morris, G.; Tarasick, D.; Forbes, G.; Nedelec, P.; Fehsenfeld, F.; Meagher, J.; Newchurch, M.; Schmidlin, F.; Turquety, S.; Crawford, J.; Pickering, K.; Cohen, R.; Bertram, T.; Wooldridge, P.; Brune, W.

    2005-12-01

    During the summer 2004 ICARTT study daily ozonesondes were launched from several sites across the eastern USA and Canada, from California to establish the baseline ozone entering the USA, and from northern Michigan to quantify ozone immediately upwind of the high emission regions in eastern North America. Additional ozone profiles across eastern North America were obtained from five instrumented commercial aircraft. The combined datasets provides the most detailed set of ozone measurements ever gathered across mid-latitude North America. To focus on purely tropospheric ozone the FLEXPART particle dispersion model was used to quantify and remove the stratospheric contribution to all profiles. Lowest ozone values in the upper troposphere were found above the west coast and north of 44 degrees. Higher values were found along the US east coast and the southeast USA with the highest values above Texas. FLEXPART was used to simulate the transport of passive NOx tracers from anthropogenic emissions in North America, intense biomass burning in Alaska and Canada, and from the locations of millions of actual lightning strikes across the continent. The upper tropospheric ozone enhancements were anti-correlated with the anthropogenic and biomass burning tracers (explained variance of 31% and 27%, respectively), but positively correlated with the lightning NOx tracer with an explained variance of 39%. While the correlations are not exceptionally strong they do imply that the excess upper tropospheric ozone above the southern USA is more likely linked to ozone production from lightning NOx rather than NOx emitted from biomass burning or anthropogenic sources

  15. Interfacial Engineering of CdO-CdSe 3D Microarchitectures with in situ Photopolymerized PEDOT for an Enhanced Photovoltaic Performance.

    Science.gov (United States)

    Lim, Iseul; Shinde, Dipak V; Patil, Supriya A; Ahn, Do Young; Lee, Wonjoo; Shrestha, Nabeen K; Lee, Joong Kee; Han, Sung-Hwan

    2015-01-01

    In the present work, porous 3D CdO-microstructured electrode obtained by pyrolysis of 3D CdCO3 microstructures is self-sensitized with CdSe using an ion exchange reaction. After sensitization, an interfacial treatment of the CdO-CdSe interface is performed by depositing a thin film of PEDOT using a photoinduce polymerization route. The microstructured electrode before and after interfacial treatment is characterized using field-emission scanning microscope, energy dispersive X-ray analyzer, contact angle measurement, UV-Visible absorption spectrophotometer and X-ray photoelectron spectrometer. After constructing a liquid junction solar cell with a Pt counter electrode, the photovoltaic performance and interfacial charge transfer kinetics across the CdO-CdSe interface before and after PEDOT treatment are investigated. The results exhibit an improved interfacial charge-transfer resistance after the PEDOT treatment, which leads to enhance the short-circuit current by 15.81% and the power conversion efficiency by 19.82%. PMID:25664985

  16. Green synthesis of Pt-on-Pd bimetallic nanodendrites on graphene via in situ reduction, and their enhanced electrocatalytic activity for methanol oxidation

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Porous 3D dendrite-like structure of Pt-on-Pd bimetallic nanostructures supported on graphene were prepared. • The surface of nanostructures was very “clean” because of the surfactant-free formation process and the use of green reagent. • The hetero-nanostructures showed excellent electrocatalytic performance in methanol oxidation. - Abstract: A green synthesis of Pt-on-Pd bimetallic nanodendrites supported on graphene (GPtPdNDs) with a Pd interior and a dendrite-like Pt exterior was achieved using a two-step preparation, mixing graphene and PdCl42? first, then adding PtCl42? and ethanol without any other solvent. The morphology, structure and composition of the thus-prepared GPtPdNDs were characterized by transmission electron microscopy (TEM), high resolution TEM, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Because no halide ions (refer in particular to Br-, I?) or surfactant was involved in the synthesis, the prepared GPtPdNDs were directly modified onto a glassy carbon electrode and showed excellent electrocatalytic performance in methanol oxidation without any pretreatments. Moreover, with the special structure of PtPdNDs and the synergetic effects of Pt and Pd and the enhanced electron transfer by graphene, the GPtPdNDs composites exhibited higher electrocatalytic activity and better tolerance to Pt nanoparticles supported on graphene (GPtNPs) and Pt/C for methanol oxidation

  17. Cellulose Nanocrystals-Bioactive Glass Hybrid Coating as Bone Substitutes by Electrophoretic Co-deposition: In Situ Control of Mineralization of Bioactive Glass and Enhancement of Osteoblastic Performance.

    Science.gov (United States)

    Chen, Qiang; Garcia, Rosalina Pérez; Munoz, Josemari; Pérez de Larraya, Uxua; Garmendia, Nere; Yao, Qingqing; Boccaccini, Aldo R

    2015-11-11

    Surface functionalization of orthopedic implants is being intensively investigated to strengthen bone-to-implant contact and accelerate bone healing process. A hybrid coating, consisting of 45S5 bioactive glass (BG) individually wrapped and interconnected with fibrous cellulose nanocrystals (CNCs), is deposited on 316L stainless steel from aqueous suspension by a one-step electrophoretic deposition (EPD) process. Apart from the codeposition mechanism elucidated by means of zeta-potential and scanning electron microscopy measurements, in vitro characterization of the deposited CNCs-BG coating in simulated body fluid reveals an extremely rapid mineralization of BG particles on the coating (e.g., the formation of hydroxyapatite crystals layer after 0.5 day). A series of comparative trials and characterization methods were carried out to comprehensively understand the mineralization process of BG interacting with CNCs. Furthermore, key factors for satisfying the applicability of an implant coating such as coating composition, surface topography, and adhesion strength were quantitatively investigated as a function of mineralization time. Cell culture studies (using MC3T3-E1) indicate that the presence of CNCs-BG coating substantially accelerated cell attachment, spreading, proliferation, differentiation, and mineralization of extracellular matrix. This study has confirmed the capability of CNCs to enhance and regulate the bioactivity of BG particles, leading to mineralized CNCs-BG hybrids for improved bone implant coatings. PMID:26460819

  18. Tensile properties of in-situ precipitated polydimethylsiloxane networks

    OpenAIRE

    Zhang, Z.; Y-L. Yue; Zhang, C.; Zhang, H; D-H. Zhang; Chen, X.; Y-F. Chen

    2013-01-01

    Tensile propertiesof polydimethylsiloxane (PDMS) networks filled with in-situ precipitated silica were investigated. Experimental results showed that increasing the swelling time of cured rubber sheets in tetraethoxysilane (TEOS) solution or elevating the humidity and temperature of precipitation reaction atmosphere can render to a positive reinforcing effect. Moreover the in-situ precipitation method can be used to further enhance the tensile properties of fumed silica filled PDMS networks. ...

  19. Electron cyclotron resonance plasma enhanced metalorganic chemical vapor deposition system with monitoring in situ for epitaxial growth of group-III nitrides

    International Nuclear Information System (INIS)

    An electron cyclotron resonance (ECR) plasma enhanced metalorganic chemical vapor deposition (PEMOCVD) system equipped with reflection high-energy electron diffraction (RHEED) has been developed and utilized for epitaxial growth of GaN and AlN on sapphire substrates by PEMOCVD. Since the multicusp cavity-coupling ECR plasma source was adopted to provide active precursors, the growth temperatures were decreased to 600-700 deg. C and the working pressures were decreased down to the region e?1.0-3.0x1010 cm-3 with a uniformity e?2-3 eV, the ion temperatures kTi?1 eV, and the plasma potentials Vso?3x10-1-8x10-1 Pa and the microwave power Pw?400-750 W. The experiment results demonstrated important roles of the plasma for sapphire substrate pretreatment, initial nucleation, and epitaxy growth of a large lattice mismatch heterojunction, GaN/(0001) Al2O3 at low temperature. The chemistry and mechanism of hydrogen (H)-plasma cleaning and nitrogen (N)-plasma nitriding, and the 30 deg. rotation of a (0001) nitride plane produced by the nitriding with respect to the (0001) Al2O3 to reduce the lattice constant mismatch are discussed. The epilayers of GaN and AlN with better quality and relatively smooth surface were obtained. The full width of half maximum (FWHM) of a GaN (0002) diffraction peak of x-ray diffraction from a 0.3 ?m thick GaN film was 15 arc min and the FWHM of AlN (0002) diffraction peak from a 0.3 ?m thick AlN film was 12 arc min. Film surface morphology was observed by atomic force microscopy

  20. Publication bias in situ

    Directory of Open Access Journals (Sweden)

    Phillips Carl V

    2004-08-01

    Full Text Available Abstract Background Publication bias, as typically defined, refers to the decreased likelihood of studies' results being published when they are near the null, not statistically significant, or otherwise "less interesting." But choices about how to analyze the data and which results to report create a publication bias within the published results, a bias I label "publication bias in situ" (PBIS. Discussion PBIS may create much greater bias in the literature than traditionally defined publication bias (the failure to publish any result from a study. The causes of PBIS are well known, consisting of various decisions about reporting that are influenced by the data. But its impact is not generally appreciated, and very little attention is devoted to it. What attention there is consists largely of rules for statistical analysis that are impractical and do not actually reduce the bias in reported estimates. PBIS cannot be reduced by statistical tools because it is not fundamentally a problem of statistics, but rather of non-statistical choices and plain language interpretations. PBIS should be recognized as a phenomenon worthy of study – it is extremely common and probably has a huge impact on results reported in the literature – and there should be greater systematic efforts to identify and reduce it. The paper presents examples, including results of a recent HIV vaccine trial, that show how easily PBIS can have a large impact on reported results, as well as how there can be no simple answer to it. Summary PBIS is a major problem, worthy of substantially more attention than it receives. There are ways to reduce the bias, but they are very seldom employed because they are largely unrecognized.

  1. Two weeks of metformin treatment enhances mitochondrial respiration in skeletal muscle of AMPK kinase dead but not wild type mice

    DEFF Research Database (Denmark)

    Kristensen, Jonas MØller; Larsen, Steen

    2013-01-01

    Metformin is used as an anti-diabetic drug. Metformin ameliorates insulin resistance by improving insulin sensitivity in liver and skeletal muscle. Reduced mitochondrial content has been reported in type 2 diabetic muscles and it may contribute to decreased insulin sensitivity characteristic for diabetic muscles. The molecular mechanism behind the effect of metformin is not fully clarified but inhibition of complex I in the mitochondria and also activation of the 5'AMP activated protein kinase (AMPK) has been reported in muscle. Furthermore, both AMPK activation and metformin treatment have been associated with stimulation of mitochondrial function and biogenesis. However, a causal relationship in skeletal muscle has not been investigated. We hypothesized that potential effects of in vivo metformin treatment on mitochondrial function and protein expressions in skeletal muscle are dependent upon AMPK signaling. We investigated this by two weeks of oral metformin treatment of muscle specific kinase dead a(2) (KD) AMPK mice and wild type (WT) littermates. We measured mitochondrial respiration and protein activity and expressions of key enzymes involved in mitochondrial carbohydrate and fat metabolism and oxidative phosphorylation. Mitochondrial respiration, HAD and CS activity, PDH and complex I-V and cytochrome c protein expression were all reduced in AMPK KD compared to WT tibialis anterior muscles. Surprisingly, metformin treatment only enhanced respiration in AMPK KD mice and thereby rescued the respiration defect compared to the WT mice. Metformin did not influence protein activities or expressions in either WT or AMPK KD mice.We conclude that two weeks of in vivo metformin treatment enhances mitochondrial respiration in the mitochondrial deficient AMPK KD but not WT mice. The improvement seems to be unrelated to AMPK, and does not involve changes in key mitochondrial proteins.

  2. Two Weeks of Metformin Treatment Enhances Mitochondrial Respiration in Skeletal Muscle of AMPK Kinase Dead but Not Wild Type Mice

    DEFF Research Database (Denmark)

    Kristensen, J. M.; Larsen, S.

    2013-01-01

    Metformin is used as an anti-diabetic drug. Metformin ameliorates insulin resistance by improving insulin sensitivity in liver and skeletal muscle. Reduced mitochondrial content has been reported in type 2 diabetic muscles and it may contribute to decreased insulin sensitivity characteristic for diabetic muscles. The molecular mechanism behind the effect of metformin is not fully clarified but inhibition of complex I in the mitochondria and also activation of the 5'AMP activated protein kinase (AMPK) has been reported in muscle. Furthermore, both AMPK activation and metformin treatment have been associated with stimulation of mitochondrial function and biogenesis. However, a causal relationship in skeletal muscle has not been investigated. We hypothesized that potential effects of in vivo metformin treatment on mitochondrial function and protein expressions in skeletal muscle are dependent upon AMPK signaling. We investigated this by two weeks of oral metformin treatment of muscle specific kinase dead alpha(2) (KD) AMPK mice and wild type (WT) littermates. We measured mitochondrial respiration and protein activity and expressions of key enzymes involved in mitochondrial carbohydrate and fat metabolism and oxidative phosphorylation. Mitochondrial respiration, HAD and CS activity, PDH and complex I-V and cytochrome c protein expression were all reduced in AMPK KD compared to WT tibialis anterior muscles. Surprisingly, metformin treatment only enhanced respiration in AMPK KD mice and thereby rescued the respiration defect compared to the WT mice. Metformin did not influence protein activities or expressions in either WT or AMPK KD mice. We conclude that two weeks of in vivo metformin treatment enhances mitochondrial respiration in the mitochondrial deficient AMPK KD but not WT mice. The improvement seems to be unrelated to AMPK, and does not involve changes in key mitochondrial proteins.

  3. In situ microbial filter used for bioremediation

    Science.gov (United States)

    Carman, M. Leslie (San Ramon, CA); Taylor, Robert T. (Roseville, CA)

    2000-01-01

    An improved method for in situ microbial filter bioremediation having increasingly operational longevity of an in situ microbial filter emplaced into an aquifer. A method for generating a microbial filter of sufficient catalytic density and thickness, which has increased replenishment interval, improved bacteria attachment and detachment characteristics and the endogenous stability under in situ conditions. A system for in situ field water remediation.

  4. Four Models of In Situ Simulation

    DEFF Research Database (Denmark)

    Musaeus, Peter; Krogh, Kristian; Paltved, Charlotte

    2014-01-01

    Introduction In situ simulation is characterized by being situated in the clinical environment as opposed to the simulation laboratory. But in situ simulation bears a family resemblance to other types of on the job training. We explore a typology of in situ simulation and suggest that there are four fruitful approaches to in situ simulation: (1) In situ simulation informed by reported critical incidents and adverse events from emergency departments (ED) in which team training is about to be cond...

  5. Triplex in-situ hybridization

    Science.gov (United States)

    Fresco, Jacques R. (Princeton, NJ); Johnson, Marion D. (East Windsor, NJ)

    2002-01-01

    Disclosed are methods for detecting in situ the presence of a target sequence in a substantially double-stranded nucleic acid segment, which comprises: a) contacting in situ under conditions suitable for hybridization a substantially double-stranded nucleic acid segment with a detectable third strand, said third strand being capable of hybridizing to at least a portion of the target sequence to form a triple-stranded structure, if said target sequence is present; and b) detecting whether hybridization between the third strand and the target sequence has occured.

  6. 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.

  7. In situ solution mining technique

    International Nuclear Information System (INIS)

    A method of in situ solution mining is disclosed in which a primary leaching process employing an array of 5-spot leaching patterns of production and injection wells is converted to a different pattern by converting to injection wells all the production wells in alternate rows

  8. An overview of in situ air sparging

    International Nuclear Information System (INIS)

    In situ air sparging (IAS) is becoming a widely used technology for remediating sites contaminated by volatile organic materials such as petroleum hydrocarbons. Published data indicate that the injection of air into subsurface water saturated areas coupled with soil vapor extraction (SVE) can increase removal rates in comparison to SVE alone for cases where hydrocarbons are distributed within the water saturated zone. However, the technology is still in its infancy and has not been subject to adequate research, nor have adequate monitoring methods been employed or even developed. Consequently, most IAS applications are designed, operated, and monitored based upon the experience of the individual practitioner. The use of in situ air sparging poses risks not generally associated with most practiced remedial technologies: air injection can enhance the undesirable off-site migration of vapors and ground water contamination plumes. Migration of previously immobile liquid hydrocarbons can also be induced. Thus, there is an added incentive to fully understand this technology prior to application. This overview of the current state of the practice of air sparging is a review of available published literature, consultation with practitioners, a range of unpublished data reports, as well as theoretical considerations. Potential strengths and weaknesses of the technology are discussed and recommendations for future investigations are given

  9. Tensile properties of in-situ precipitated polydimethylsiloxane networks

    Directory of Open Access Journals (Sweden)

    Z. Zhang

    2013-10-01

    Full Text Available Tensile propertiesof polydimethylsiloxane (PDMS networks filled with in-situ precipitated silica were investigated. Experimental results showed that increasing the swelling time of cured rubber sheets in tetraethoxysilane (TEOS solution or elevating the humidity and temperature of precipitation reaction atmosphere can render to a positive reinforcing effect. Moreover the in-situ precipitation method can be used to further enhance the tensile properties of fumed silica filled PDMS networks. The reinforcement introduced by the in-situ precipitated silica gel particles can probably be attributed to the adsorption of polymer chains onto silica surface, the pinning effect of polymer chains within gel particles, and the fillerfiller gel structure among gel particles.

  10. Direct in situ RT-PCR

    OpenAIRE

    Merighi, Adalberto; GAMBINO, Graziana; Lossi, Laura; SALIO, Chiara

    2011-01-01

    In situ polymerase chain reaction (PCR) is a histological technique that exploits the advantages of PCR for detection of mRNA directly in tissue sections. It somehow conjugates together PCR and in situ hybridization that is more traditionally employed for mRNA localization in cell organelles, intact cells, or tissue sections. This chapter describes the application of in situ PCR for neuropeptide mRNA localization. We provide here a detailed protocol for direct in situ reverse transcription (R...

  11. Polyolefin nanocomposites in situ polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Galland, Griselda Barrera; Fim, Fabiana de C.; Milani, Marceo A.; Silva, Silene P. da; Forest, Tadeu; Radaelli, Gislaine, E-mail: griselda.barrera@ufrgs.br [Universidade Federal do Rio Grande de Sul - UFRGS, Porto Alegre, RS (Brazil); Basso, Nara R.S. [Pontificia Universidade Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil); Quijada, Raul [Universidad de Chile, Santiago (Chile)

    2011-07-01

    Polyethylene and polypropylene nanocomposites using grapheme nanosheets and treated chrysotile have been synthesized by in situ polymerization using metallocene catalysts. The fillers have been submitted to acid, thermal and/ou ultrasound treatments before to introduce them into the polymerization reactor. A complete characterization of the fillers has been done. The nanocomposites have been characterized by SEM, TEM, DRX and AFM. The thermal, mechanic -dynamic, mechanical and electrical properties of the nanocomposites are discussed. (author)

  12. Polyolefin nanocomposites in situ polymerization

    International Nuclear Information System (INIS)

    Polyethylene and polypropylene nanocomposites using grapheme nanosheets and treated chrysotile have been synthesized by in situ polymerization using metallocene catalysts. The fillers have been submitted to acid, thermal and/ou ultrasound treatments before to introduce them into the polymerization reactor. A complete characterization of the fillers has been done. The nanocomposites have been characterized by SEM, TEM, DRX and AFM. The thermal, mechanic -dynamic, mechanical and electrical properties of the nanocomposites are discussed. (author)

  13. Oldest biliary endoprosthesis in situ

    Directory of Open Access Journals (Sweden)

    Pierluigi Consolo

    2013-01-01

    Full Text Available The advantages of endoscopic retrograde cholangiopancreatography over open surgery have made it the predominant method of treating patients with choledocholithiasis. After sphincterotomy, however, 10%-15% of common bile duct stones cannot be removed with a basket or balloon. The methods for managing “irretrievable stones” include surgery, mechanical lithotripsy, intraductal or extracorporeal shock wave lithotripsy and biliary stenting. The case presented was a referred 82-year-old Caucasian woman with a 7-year-old plastic biliary endoprosthesis in situ. To the best of our knowledge the examined endoprosthesis is the oldest endoprosthesis in situ reported in the literature. Endoscopic biliary endoprosthesis placement remains a simple and safe procedure for patients with stones that are difficult to manage by conventional endoscopic methods and for patients who are unfit for surgery or who are high surgical risks. To date no consensus has been reached regarding how long a biliary prosthesis should remain in situ. Long-term biliary stenting may have a role in selected elderly patients if stones extraction has failed because the procedure may prevent stones impaction and cholangitis.

  14. In Situ Magnetic Separation for Extracellular Protein Production

    DEFF Research Database (Denmark)

    Kappler, T.; Cerff, Martin

    2009-01-01

    A new approach for in situ product removal from bioreactors is presented in which high-gradient magnetic separation is used. This separation process was used for the adsorptive removal of proteases secreted by Bacillus licheniformis. Small, non-porous bacitracin linked magnetic adsorbents were employed directly in the broth during the fermentation, followed by in situ magnetic separation, Proof of the concept was first demonstrated in shake flask culture, then scaled up and applied during a fed batch cultivation ill a 3.7 L bioreactor. It could be demonstrated that growth of B. licheniformis was not influenced by the in situ product removal step. Protease production also remained the same after the separation step. Furthermore, degradation of the protease, which followed first order kinetics, was reduced by using the method. Using a theoretical modeling approach, we Could show that protease yield in total was enhanced by using in situ magnetic separation. The process described here is a promising technique toimprove overall yield in No production processes which are often limited due to weak downstream operations, Potential limitations encountered during a bioprocess can be overcome such as product inhibition or degradation. We also discuss the key points where research is needed to implement in situ magnetic separation in industrial production.

  15. 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.

  16. Actinobacillus pleuropneumoniae osteomyelitis in pigs demonstrated by fluorescent in situ hybridization

    DEFF Research Database (Denmark)

    Jensen, Tim Kåre; Boye, Mette; Hagedorn-Olsen, T.; Riising, H.J.; Angen, Øystein

    1999-01-01

    Necrotizing osteomyelitis and fibrinopurulent arthritis with isolation of Actinobacillus pleuropneumoniae serotype 2 is reported in two pigs from a herd with lameness and mild coughing problems among 8 to 12-week-old pigs. Application of fluorescent in situ hybridization targeting 16S ribosomal RNA of A. pleuropneumoniae in formalin-fixed tissue was performed to verify the association of A. pleuropneumoniae with the bone and joint lesions. By in situ hybridization A. pleuropneumoniae was demonst...

  17. Composite with In Situ Plenums

    Science.gov (United States)

    Montesano, Mark

    2012-01-01

    A document describes a high-performance thermal distribution panel (TDP) concept using high-conductivity (greater than 800 W/mK) macro composite skin with in situ heat pipes. The processing technologies proposed to build such a panel result in a one-piece, inseparable assembly with high conductance in both the X and Y planes. The TDP configuration can also be used to produce panels with high structural stiffness. The one-piece construction of the TDP eliminates the thermal interface between the cooling plenums and the heat spreader base, and obviates the need for bulky mounting flanges and thick heat spreaders used on baseline designs. The conductivity of the TDP can be configured to exceed 800 W/mK with a mass density below 2.5 grams per cubic centimeter. This material can provide efficient conductive heat transfer between the in situ heat plenums, permitting the use of thinner panel thicknesses. The plenums may be used as heat pipes, loop heat pipes, or liquid cooling channels. The panel technology used in the TDP is a macro-composite comprised of aluminum-encapsulated annealed pyrolytic graphite (APG). APG is highly aligned crystalline graphite with an in-plane thermal conductivity of 1,700 W/mK. APG has low shear strength and does not constrain the encapsulating material. The proposed concept has no thermal interfaces between the heat pipes and the spreader plate, further improving the overall conductance of the system. The in situ plenums can also be used for liquid cooling applications. The process can be used to fabricate structural panels by adding a second thin sheet.

  18. Hodoscope in-situ radiography

    International Nuclear Information System (INIS)

    The fast-neutron hodoscopes at TREAT and proposed for STF can be adapted to perform high-resolution radiography, in addition to their role of time-resolved test fuel imaging. Time resolution may be traded for increased spatial resolution by remote motorized scanning of the collimator, simulataneous collection of data from the detector array over extended time intervals, and deconvolution of the data from the collimator response function. Calculations and analysis of initial scanning experiments at TREAT indicate that an acceptable level of fuel density resolution can be achieved for TREAT and STF in-situ radiography

  19. Gold-Facilitated in Situ Hybridization : A Bright-Field Autometallographic Alternative to Fluorescence in Situ Hybridization for Detection of HER-2/neu Gene Amplification

    OpenAIRE

    Tubbs, Raymond; Pettay, James; Skacel, Marek; Powell, Richard; Stoler, Mark; Roche, Patrick; Hainfeld, James

    2002-01-01

    Fluorescence in situ hybridization (FISH) represents an excellent method for profiling gene amplification in situ, but correlation with tissue morphology is difficult because of dark-field visualization. Validation of a bright-field assay for assessment of HER-2/neu gene amplification was investigated. Streptavidin-Nanogold was used to generate bright-field gene copy signals using GoldEnhance gold-based autometallography, catalyzed reported deposition, and a biotin-labeled probe. One hundred ...

  20. Methods and systems for in-situ electroplating of electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Zappi, Guillermo Daniel; Zarnoch, Kenneth Paul; Huntley, Christian Andrew; Swalla, Dana Ray

    2015-06-02

    The present techniques provide electrochemical devices having enhanced electrodes with surfaces that facilitate operation, such as by formation of a porous nickel layer on an operative surface, particularly of the cathode. The porous metal layer increases the surface area of the electrode, which may result in increasing the efficiency of the electrochemical devices. The formation of the porous metal layer is performed in situ, that is, after the assembly of the electrodes into an electrochemical device. The in situ process offers a number of advantages, including the ability to protect the porous metal layer on the electrode surface from damage during assembly of the electrochemical device. The enhanced electrode and the method for its processing may be used in any number of electrochemical devices, and is particularly well suited for electrodes in an electrolyzer useful for splitting water into hydrogen and oxygen.

  1. Effectiveness of weekly cognitive stimulation therapy for people with dementia and the additional impact of enhancing cognitive stimulation therapy with a carer training program

    Directory of Open Access Journals (Sweden)

    Cove J

    2014-12-01

    Full Text Available Jennifer Cove,1 Nicola Jacobi,2 Helen Donovan,3 Martin Orrell,4 Josh Stott,5 Aimee Spector5 1Department of Clinical, Educational and Health Psychology, University College London, London, 2Department of Psychology, City University, London, 3Clinical Psychology Service, South Essex Partnership NHS Foundation Trust, Bedford, 4Department of Psychiatry, 5Department of Clinical, Educational and Health Psychology, University College London, London, UKPurpose of the study: Cognitive stimulation therapy (CST is a widely used, evidence-based intervention for people with dementia (PwD. Although designed as a 14 session, twice weekly intervention, many services in the UK deliver CST once a week for 14 weeks. However, this method of delivery has yet to be evaluated. In addition, CST does not include any formal carer training. This study aimed to evaluate the effectiveness of once weekly CST and determine any additional impact when enhanced with a carer training program.Design and methods: A single blind, randomized controlled trial was conducted. Sixty eight PwD and their carers were recruited through three community Memory Assessment Services. PwD and their carers were randomized to one of three conditions: CST plus carer training, CST only, or a wait list control. PwD were administered standardized measures of cognition, quality of life, and quality of relationship with carer at baseline and the 15 week follow-up.Results: There were no baseline differences across the three groups. At follow-up, there were no significant differences between PwD in the three groups on any outcomes. Implications: Weekly CST with or without carer training may not be an effective form of delivery. Several possible explanations for the outcomes are proposed. Weekly CST may not offer the necessary “dose” required to combat decline, and equally the carer training may have been too brief to have made a difference. Services currently offering weekly CST should collect routine outcome data to support its use and provide practice-based evidence.Keywords: Alzheimer’s disease, cognition, intervention, caregiver

  2. DOE In Situ Remediation Integrated Program

    International Nuclear Information System (INIS)

    The In Situ Remediation Integrated Program (ISRP) supports and manages a balanced portfolio of applied research and development activities in support of DOE environmental restoration and waste management needs. ISRP technologies are being developed in four areas: containment, chemical and physical treatment, in situ bioremediation, and in situ manipulation (including electrokinetics). the focus of containment is to provide mechanisms to stop contaminant migration through the subsurface. In situ bioremediation and chemical and physical treatment both aim to destroy or eliminate contaminants in groundwater and soils. In situ manipulation (ISM) provides mechanisms to access contaminants or introduce treatment agents into the soil, and includes other technologies necessary to support the implementation of ISR methods. Descriptions of each major program area are provided to set the technical context of the ISM subprogram. Typical ISM needs for major areas of in situ remediation research and development are identified

  3. In situ treatability test plan

    International Nuclear Information System (INIS)

    This document describes the plans for the in situ treatment zone (ISTZ) treatability test for groundwater contaminated with strontium-90. The treatability test is to be conducted at the Hanford Site in Richland, Washington, in a portion of the 100-N Area adjacent to the Columbia River referred to as N-Springs. The purpose of the treatability test is to evaluate the effectiveness of an innovative technology to prevent the discharge of strontium-90 contaminated groundwater into the Columbia River. The ISTZ is a passive technology that consists of placing a treatment agent in the path of the groundwater. The treatment agent must restrict target radioactive contaminants and provide time for the contaminant to decay to acceptable levels. The permeability of the treatment zone must be greater than or equal to that of the surrounding sediments to ensure that the contaminated groundwater flows through the treatment zone agent and not around the agent

  4. Breast Ductal Carcinoma in Situ: Morphologic and Kinetic MRI Findings

    International Nuclear Information System (INIS)

    Adequate diagnosis of ductal carcinoma in situ (DCIS) could lead to efficacious treatment. Due to the fact that DCIS lesions can progress to invasive carcinomas and that the sensitivity of the standard examination – mammography – is between 70 and 80%, use of a more sensitive diagnostic tool was needed. In detection of DCIS, contrast-enhanced magnetic resonance imaging (CE-MRI) has the sensitivity up to 96%. Morphological features and kinetic parameters were evaluated to define the most regular morphological, kinetic and morpho-kinetic patterns on MRI assessment of breast ductal carcinoma in situ (DCIS). We retrospectively assessed eighteen patients with 23 histologically confirmed lesions (mean age, 52.4 ± 10.5 years). All patients were clinically and mammographically examined prior to MRI examination. DCIS appeared most frequently as non-mass-like lesions (12 lesions, 52.17%). The differences in the frequency of lesion types were statistically significant (P<0.05). The following morphological patterns were detected: A: no specific morphologic features, B: linear/branching enhancement, C: focal mass-like enhancement, D: segmental enhancement, E: segmental enhancement in triangular shape, F: diffuse enhancement, G: regional heterogeneous enhancement in one quadrant not conforming to duct distribution and H: dotted or granular type of enhancement with patchy distribution. The difference in the frequency of the proposed patterns was statistically significant (P<0.05). There were eight lesions with mass enhancement, and six with segmental lesions: regional and triangular. There was no statistically significant difference in the frequency of enhancement curve types (P>0.05). There was no significant difference in the frequency of morpho-kinetic patterns. Non-mass-like lesions, lesions with focal or segmental distribution, with a “plateau” enhancement curve type were the most frequent findings of DCIS lesions on MRI

  5. Magic angle spinning nuclear magnetic resonance apparatus and process for high-resolution in situ investigations

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jian Zhi; Sears, Jr., Jesse A.; Hoyt, David W.; Mehta, Hardeep S.; Peden, Charles H. F.

    2015-11-24

    A continuous-flow (CF) magic angle sample spinning (CF-MAS) NMR rotor and probe are described for investigating reaction dynamics, stable intermediates/transition states, and mechanisms of catalytic reactions in situ. The rotor includes a sample chamber of a flow-through design with a large sample volume that delivers a flow of reactants through a catalyst bed contained within the sample cell allowing in-situ investigations of reactants and products. Flow through the sample chamber improves diffusion of reactants and products through the catalyst. The large volume of the sample chamber enhances sensitivity permitting in situ .sup.13C CF-MAS studies at natural abundance.

  6. In situ vitrification: A review

    International Nuclear Information System (INIS)

    The in situ vitrification process (ISV) converts contaminated soils and sludges to a glass and crystalline product. The process appears to be ideally suited for on site treatment of both wet and dry wastes. Basically, the system requires four molybdenum electrodes, an electrical power system for vitrifying the soil, a hood to trap gaseous effluents, an off-gas treatment system, an off-gas cooling system, and a process control station. Mounted in three transportable trailers, the ISV process can be moved from site to site. The process has the potential for treating contaminated soils at most 13 m deep. The ISV project has won a number of outstanding achievement awards. The process has also been patented with exclusive worldwide rights being granted to Battelle Memorial Institute for nonradioactive applications. While federal applications still belong to the Department of Energy, Battelle transferred the rights of ISV for non-federal government, chemical hazardous wastes to a separate corporation in 1989 called Geosafe. This report gives a review of the process including current operational behavior and applications

  7. In situ Gas Conditioning in Fuel Reforming for Hydrogen Generation

    Energy Technology Data Exchange (ETDEWEB)

    Bandi, A.; Specht, M.; Sichler, P.; Nicoloso, N.

    2002-09-20

    The production of hydrogen for fuel cell applications requires cost and energy efficient technologies. The Absorption Enhanced Reforming (AER), developed at ZSW with industrial partners, is aimed to simplify the process by using a high temperature in situ CO2 absorption. The in situ CO2 removal results in shifting the steam reforming reaction equilibrium towards increased hydrogen concentration (up to 95 vol%). The key part of the process is the high temperature CO2 absorbent. In this contribution results of Thermal Gravimetric Analysis (TGA) investigations on natural minerals, dolomites, silicates and synthetic absorbent materials in regard of their CO2 absorption capacity and absorption/desorption cyclic stability are presented and discussed. It has been found that the inert parts of the absorbent materials have a structure stabilizing effect, leading to an improved cyclic stability of the materials.

  8. An amplified electrochemical immunosensor based on in situ-produced 1-naphthol as electroactive substance and graphene oxide and Pt nanoparticles functionalized CeO2 nanocomposites as signal enhancer.

    Science.gov (United States)

    Yang, Zhe-Han; Zhuo, Ying; Yuan, Ruo; Chai, Ya-Qin

    2015-07-15

    In this work, an amplified electrochemical immunosensor based on 1-naphthol as electroactive substance and Pt/CeO2/GO composites as catalytic amplifier was constructed for sensitive detection influenza. Through "sandwich" reaction, the Pt/CeO2/GO functionalized bioconjugates were captured on electrode surface and the electrochemical signal directly originated from 1-naphthol, which was in situ produced with high local concentration though the hydrolysis of 1-naphthyl phosphate catalyzed by ALP. Then, 1-naphthol as new reactant was oxidized by Pt/CeO2/GO composites with outstanding catalytic performance, resulting in detection signal amplification. In addition, as compared to label electroactive substance to antibodies, a simplified preparative step of immunosensor could be achieved because the signal probe get rid of introducation other electroactive substances. The proposed immunosensor achieved a linear range of 1.0×10(-3)-1.0ngmL(-1) and 5.0 to 1.0×10(2)ngmL(-1) with a detection limit of 0.43pgmL(-1) (defined as S/N=3). PMID:25791337

  9. Enhancement of growth and structure properties of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} thin layers by in situ incorporation of gold nano-clusters

    Energy Technology Data Exchange (ETDEWEB)

    Erlebach, Ralf; Huebner, Michael; Christke, Sandra; Grosse, Veit; Schmidl, Frank; Seidel, Paul [Friedrich-Schiller-University Jena, Institute of Solid State Physics, Helmholtzweg 5, 07743 Jena (Germany); Kraeusslich, Juergen [Friedrich-Schiller-University Jena, Institute of Optics and Quantum Electronics, Max-Wien-Platz 1, 07743 Jena (Germany); Rettenmayr, Markus [Friedrich-Schiller-University Jena, Institute of Materials Science and Technology, Loebdergraben 32, 07743 Jena (Germany)

    2011-07-01

    For most hetero-epitactic growth techniques, structural defects due to the lattice misfit, namely tilts, precipitates or holes, turn out to be limiting factors for the successful fabrication of multilayer systems. A new approach of an in situ growth technique dealing with this problem by incorporation of gold nano-clusters is examined. Therefore, pulsed laser deposition (PLD) of a high-T{sub C} YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) layer onto a strontium titanate (STO) template with a temporary interlayer of gold with a well-defined film thickness is investigated. Within this process, the gold interlayer shows nano-clustering behavior. Effects on the properties of structure like crystallographic or surface features of the ablated YBCO layer by variation of the film thickness of the gold and YBCO layers are presented. Moreover, distribution and clustering behavior of the crystallized gold nano-particles as well as the basic superconducting properties of the layer system are analyzed.

  10. Spontaneous heterotopic pregnancy causing tubal rupture in a patient with intrauterine device in-situ

    OpenAIRE

    Serpil Telci; Cihan Kaya; Levent Yasar; Murat Ekin

    2014-01-01

    Spontaneous heterotopic pregnancy (HP) is a rare but life threatening condition. A case of 27 years old patient who admitted to our emergency gynecology clinic for acute abdominal pain is presented. The transvaginal ultrasound revealed two embryos with cardiac activity; one intrauterine (8 week and 3 day) , and the other one in the left adnexa (7 week and 3 day) and an intrauterine device (IUD) in situ. The patient had left salpingectomy with laparotomy and after the fifth hour of operation s...

  11. In-situ Ground-Based and Airborne Formaldehyde Measurements in the Houston Area During TexAQS-II

    Science.gov (United States)

    Rappenglueck, B.; Byun, D.; Alvarez, S.; Buhr, M.; Coarfa, V.; Czader, B.; Dasgupta, P.; Estes, M.; Kim, S.; Leuchner, M.; Luke, W.; Shauck, M.; Zanin, G.

    2007-12-01

    Formaldehyde is considered to play a significant role in summertime photochemistry in the Houston area, in particular it is considered an important source for radicals. Secondary formation seems to be the most important fraction of ambient HCHO. Enhanced nighttime values may indicate primary sources. Potential sources may include mobile sources such as traffic exhaust, in particular not well maintained Diesel engines. Other possible sources may include point sources such as coffee roasting and flares from refineries. In this study we focused on the TexAQS-II continuous in-situ formaldehyde data set based on Hantzsch reaction which was obtained in the Ship Channel area (HRM3 and Lynchburg Ferry site) and at the Moody Tower for several weeks. We also include in-situ HCHO measurements obtained with the same technique aboard the Baylor aircraft during TexAQS-II flight missions. Formaldehyde data was compared to several trace gases that are supposed to be coemitted including CO (traffic), ethylene (flares), and SO2 (industry). In order to keep photochemical processes at a minimum special focus was on nighttime data. Case studies will be discussed where meteorological conditions including recirculation and boundary layer developments seem to play a major role in the redistribution of HCHO. Observations will be compared to CMAQ model studies.

  12. Simultaneous in situ magnetospheric and ionospheric detection of detached plasmas

    Science.gov (United States)

    Miller, N. J.; Grebowsky, J. M.

    1977-01-01

    On January 19, 1972, in situ measurements by Explorer 45, orbiting in the magnetosphere near the equatorial plane, and ISIS 2, in a circular polar orbit at 1400 km, simultaneously detected patches of enhanced ionization outside the main body of the plasmasphere. The magnetospheric plasma region extended between (geomagnetic latitude) L values 3.4-4.8 and the ionospheric electron density enhancement extended between L values 3.6-4.4. The two plasma features were detected near 22 hours magnetic local time (MLT). Based on a number of observations, it is inferred that the plasma density enhancement persisted for more than 5 hours and extended over at least 2 hours in MLT near L = 5. These results provide experimental evidence that some detached magnetospheric plasma regions are signatures of a flux tube containing enhanced ionization throughout a volume extending from the topside ionosphere out to the equator.

  13. Diclofenac enables unprecedented week-long microneedle-enhanced delivery of a skin impermeable medication in humans

    Science.gov (United States)

    Brogden, Nicole K.; Banks, Stan L.; Crofford, Leslie J.; Stinchcomb, Audra L.

    2013-01-01

    Microneedles applied to the skin create micropores, allowing transdermal drug delivery of skin-impermeable compounds. The first human study with this technique demonstrated delivery of naltrexone (an opioid antagonist) for two to three days. Rapid micropore closure, however, blunts the delivery window. Application of diclofenac (an anti-inflammatory) allows seven days of naltrexone delivery in animals. Purpose the purpose of the current work was to demonstrate delivery of naltrexone for seven days following one microneedle treatment in humans. Methods Human subjects were treated with microneedles, diclofenac (or placebo), and naltrexone. Impedance measurements were used as a surrogate marker to measure micropore formation, and plasma naltrexone concentrations were measured for seven days post-microneedle application. Results Impedance dropped significantly from baseline to post-microneedle treatment, confirming micropore formation. Naltrexone was detected for seven days in Group 1 (diclofenac + naltrexone, n = 6), vs. 72 hours in Group 2 (placebo + naltrexone, n = 2). At study completion, a significant difference in impedance was observed between intact and microneedle-treated skin in Group 1 (confirming the presence of micropores). Conclusion This is the first study demonstrating week-long drug delivery after one microneedle application, which would increase patient compliance and allow delivery of therapies for chronic diseases. PMID:23761054

  14. Development, characterization and application of in situ gel systems for intranasal delivery of tacrine.

    Science.gov (United States)

    Qian, Shuai; Wong, Yin Cheong; Zuo, Zhong

    2014-07-01

    The present study aimed to develop an in situ gel formulation for intranasal delivery of tacrine (THA), an anti-Alzheimer's drug. Thermosensitive polymer Pluronic F-127 was used to prepare THA in situ gels. Sol-gel transition temperature (Tsol-gel), rheological properties, in vitro release, and in vivo nasal mucociliary transport time were optimized. The pharmacokinetics and brain dispositions of in situ gel were compared with that from THA oral solution in rats. The in situ gel demonstrated a liquid state with Newtonian fluid behavior under 20 °C, while it exhibited as non-flowing gel with pseudoplastic fluid behavior beyond its Tsol-gel of 28.5 °C. Based on nasal mucociliary transport time, the in situ gel significantly prolonged its retention in nasal cavity compared to solution form. Moreover, the in situ gel achieved 2-3 fold higher peak plasma concentration (Cmax) and area under the curve (AUC) of THA in plasma and brain tissue, but lowered Cmax and AUC of the THA metabolites compared to that of oral solution. The enhanced nasal residence time, improved bioavailability, increased brain uptake of parent drug and decreased exposure of metabolites suggested that the in situ gel could be an effective intranasal formulation for THA. PMID:24709220

  15. Two weeks of metformin treatment induces AMPK-dependent enhancement of insulin-stimulated glucose uptake in mouse soleus muscle

    DEFF Research Database (Denmark)

    Kristensen, Jonas MØller; Treebak, Jonas T

    2014-01-01

    Metformin-induced activation of the 5'-AMP-activated protein kinase (AMPK) has been associated with enhanced glucose uptake in skeletal muscle, but so far no direct causality has been examined. We hypothesized that an effect of in vivo metformin treatment on glucose uptake in mouse skeletal muscles is dependent on AMPK signaling. Oral doses of metformin or saline treatment were given to muscle-specific kinase dead (KD) AMPK?2 mice and wild-type (WT) littermates either once or chronically for 2 wk. Soleus and extensor digitorum longus muscles were used for measurements of glucose transport and Western blot analyses. Chronic treatment with metformin enhanced insulin-stimulated glucose uptake in soleus muscles of WT (?45%, P < 0.01) but not of AMPK KD mice. Insulin signaling at the level of Akt protein expression or Thr(308) and Ser(473) phosphorylation was not changed by metformin treatment. Insulin signaling at the level of Akt and TBC1D4 protein expression as well as Akt Thr(308)/Ser(473) and TBC1D4 Thr(642)/Ser(711) phosphorylation were not changed by metformin treatment. Also, protein expressions of Rab4, GLUT4, and hexokinase II were unaltered after treatment. The acute metformin treatment did not affect glucose uptake in muscle of either of the genotypes. In conclusion, we provide novel evidence for a role of AMPK in potentiating the effect of insulin on glucose uptake in soleus muscle in response to chronic metformin treatment.

  16. Scientific rationale of Saturn's in situ exploration

    CERN Document Server

    Mousis, O; Lebreton, J -P; Wurz, P; Cavalié, T; Coustenis, A; Courtin, R; Gautier, D; Helled, R; Irwin, P G J; Morse, A D; Nettelmann, N; Marty, B; Rousselot, P; Venot, O; Atkinson, D H; Waite, J H; Reh, K R; Simon-Miller, A; Atreya, S; André, N; Blanc, M; Daglis, I A; Fischer, G; Geppert, W D; Guillot, T; Hedman, M M; Hueso, R; Lellouch, E; Lunine, J I; Murray, C D; O'Donoghue, J; Rengel, M; Sanchez-Lavega, A; Schmider, F -X; Spiga, A; Spilker, T; Petit, J -M; Tiscareno, M S; Ali-Dib, M; Altwegg, K; Bouquet, A; Briois, C; Fouchet, T; Guerlet, S; Kostiuk, T; Lebleu, D; Moreno, R; Orton, G S; Poncy, J

    2014-01-01

    Remote sensing observations meet some limitations when used to study the bulk atmospheric composition of the giant planets of our solar system. A remarkable example of the superiority of in situ probe measurements is illustrated by the exploration of Jupiter, where key measurements such as the determination of the noble gases abundances and the precise measurement of the helium mixing ratio have only been made available through in situ measurements by the Galileo probe. This paper describes the main scientific goals to be addressed by the future in situ exploration of Saturn placing the Galileo probe exploration of Jupiter in a broader context and before the future probe exploration of the more remote ice giants. In situ exploration of Saturn's atmosphere addresses two broad themes that are discussed throughout this paper: first, the formation history of our solar system and second, the processes at play in planetary atmospheres. In this context, we detail the reasons why measurements of Saturn's bulk element...

  17. In situ leach: technology and potential

    International Nuclear Information System (INIS)

    In-situ leach and solution mining are described with respect to uranium mining. In the technique, leaching fluids dissolve the mineral without having to remove the ore physically from its occurence. In-situ leach can produce uranium at lower costs than other methods. The factors which are important to achieve this are discussed. In-situ leach is only suitable for one type of uranium deposit, a roll-front deposit (deposited from moving groundwater) in a permeable sandstone that must be an aquifer (sandstone filled with water). It is difficult to predict the performance of an in-situ leach project; good engineering techniques are more important than in conventional mining. The processing and subsequent recovery of the uranium are described. Some of the technological improvements in the technique are discussed. The future development of the technique is considered. (U.K.)

  18. In situ dehydration of yugawaralite

    DEFF Research Database (Denmark)

    Artioli, G.; Ståhl, Kenny

    2001-01-01

    The structural response of the natural zeolite yugawaralite (CaAl2Si6O16. 4H(2)O) upon thermally induced dehydration has been studied by Rietveld analysis of temperature-resolved powder diffraction data collected in situ in the temperature range 315-791 K using synchrotron radiation. The room-temperature monoclinic structure [Pc, a = 6.73200(9), b = 14.0157(2), c = 10.0607(1) Angstrom, beta = 111.189(1) degrees, Z = 2, at 315 K] has the Ca cations in the channels coordinated to four framework O atoms and to four water molecules, with two of the water sites (OW1 and OW4) showing positional disorder progressively disappearing as the dehydration proceeds. The yugawaralite structure reacts to the release of water molecules with small changes in the Ca-O bond distances and minor distortions of the tetrahedral framework up to about 695 K. Above this temperature the Ca coordination falls below 7 (four framework O atoms and three water molecules) and a major rearrangement in the cation coordination takes place, causing a first order phase transition involving both a large decrease in the cell volume and the change in the space group symmetry. A satisfactory structure model for the high-temperature phase stable in the range 695-791 K could not be obtained because of the complexity of the structure. A model approximately describing the average structure [Pn, a = 12.703(1), b = 13.067(1), c = 9.839(1) Angstrom, beta = 110.894(9), Z = 4, at 749 K] has been used to follow the temperature evolution of the cell parameters in the measured temperature range. This model involves a sixfold coordination of the Ca cations (five framework O atoms and one water molecule). There is no indication of significant structure changes before collapse, likely occurring when the last water molecule is expelled from the structure and the cation coordination drops below 6, as observed in other Ca-rich zeolites (i.e., laumontite, scolecite, mesolite).

  19. 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

  20. Demonstration testing and evaluation of in situ soil heating

    International Nuclear Information System (INIS)

    A Treatability Study planned for the demonstration of the in situ electromagnetic (EM) heating process to remove organic solvents is described in this Work Plan. The treatability study will be conducted by heating subsurface vadose-zone soils in an organic plume adjacent to the Classified Burial Ground K-1070-D located at K-25 Site, Oak Ridge. The test is scheduled to start during the fourth quarter of FY94 and will be completed during the first quarter of FY95. The EM heating process for soil decontamination is based on volumetric heating technologies developed during the '70s for the recovery of fuels from shale and tar sands by IIT Research Institute (IITRI) under a co-operative program with the US Department of Energy (DOE). Additional modifications of the technology developed during the mid '80s are currently used for the production of heavy oil and waste treatment. Over the last nine years, a number of Government agencies (EPA, Army, AF, and DOE) and industries sponsored further development and testing of the in situ heating and soil decontamination process for the remediation of soils containing hazardous organic contaminants. In this process the soil is heated in situ using electrical energy. The contaminants are removed from the soil due to enhanced vaporization, steam distillation and stripping. IITRI will demonstrate the EM Process for in situ soil decontamination at K-25 Site under the proposed treatability study. Most of the contaminants of concern are volatile organics which can be removed by heating the soil to a temperature range of 85 to 95 C. The efficiency of the treatment will be determined by comparing the concentration of contaminants in soil samples. Samples will be obtained before and after the demonstration for a measurement of the concentration of contaminants of concern

  1. In Vivo Osteogenic Differentiation of Human Embryoid Bodies in an Injectable in Situ-Forming Hydrogel

    OpenAIRE

    Moon Suk Kim; Seung-Yup Ku; Shin Yong Moon; Yoon Young Kim; Hai Bang Lee; Da Yeon Kim

    2013-01-01

    In this study, we examined the in vivo osteogenic differentiation of human embryoid bodies (hEBs) by using an injectable in situ-forming hydrogel. A solution containing MPEG-b-(polycaprolactone-ran-polylactide) (MCL) and hEBs was easily prepared at room temperature. The MCL solution with hEBs and osteogenic factors was injected into nude mice and developed into in situ-forming hydrogels at the injection sites; these hydrogels maintained their shape even after 12 weeks in vivo, thereby indicat...

  2. Tracking Mitochondrial DNA In Situ.

    Science.gov (United States)

    Ligasová, Anna; Koberna, Karel

    2016-01-01

    The methods of the detection of (1) non-labeled and (2) BrdU-labeled mitochondrial DNA (mtDNA) are described. They are based on the production of singlet oxygen by monovalent copper ions and the subsequent induction of DNA gaps. The ends of interrupted DNA serve as origins for the labeling of mtDNA by DNA polymerase I or they are utilized by exonuclease that degrades DNA strands, unmasking BrdU in BrdU-labeled DNA. Both methods are sensitive approaches without the need of additional enhancement of the signal or the use of highly sensitive optical systems. PMID:26530676

  3. In situ bioremediation of trichloroethylene-contaminated water by a resting-cell methanotrophic microbial filter

    International Nuclear Information System (INIS)

    The Lawrence Livermore National Laboratory is testing and developing an in situ microbial filter technology for remediating migrating subsurface plumes contaminated with low concentrations of trichloroethylene (TCE). Their current focus is the establishment of a replenishable bioactive zone (catalytic filter) along expanding plume boundaries by the Injection of a representative methanotrophic bacterium, Methylosinus trichosporium OB3b. We have successfully demonstrated this microbial filter strategy using emplaced, attached resting cells (no methane additions) in a 1.1-m flow-through test bed loaded with water-saturated sand. Two separate 24 h pulses of TCE (109 ppb and 85 ppb), one week apart, were pumped through the system at a flow velocity of 1.5 cm/h; no TCE (<0.5 ppb) was detected on the downstream side of the microbial filter. Subsequent excavation of the wet sand confirmed the existence of a TCE-bioactive zone 19 days after it had been created. An enhanced longevity of the cellular, soluble-form methane monooxygenase produced by this methanotroph Is a result of our laboratory bioreactor culturing conditions. Additional experiments with cells in sealed vials and emplaced in the 1.1-m test bed yielded a high resting-cell finite TCE biotransformation capacity of ? 0.25 mg per mg of bacteria; this is suitable for a planned sand-filled trench field demonstration at a Lawrence Livermore National Laboratory site

  4. Aquifer restoration at in-situ leach uranium mines: evidence for natural restoration processes

    Energy Technology Data Exchange (ETDEWEB)

    Deutsch, W.J.; Serne, R.J.; Bell, N.E.; Martin, W.J.

    1983-04-01

    Pacific Northwest Laboratory conducted experiments with aquifer sediments and leaching solution (lixiviant) from an in-situ leach uranium mine. The data from these laboratory experiments and information on the normal distribution of elements associated with roll-front uranium deposits provide evidence that natural processes can enhance restoration of aquifers affected by leach mining. Our experiments show that the concentration of uranium (U) in solution can decrease at least an order of magnitude (from 50 to less than 5 ppM U) due to reactions between the lixiviant and sediment, and that a uranium solid, possibly amorphous uranium dioxide, (UO/sub 2/), can limit the concentration of uranium in a solution in contact with reduced sediment. The concentrations of As, Se, and Mo in an oxidizing lixiviant should also decrease as a result of redox and precipitation reactions between the solution and sediment. The lixiviant concentrations of major anions (chloride and sulfate) other than carbonate were not affected by short-term (less than one week) contact with the aquifer sediments. This is also true of the total dissolved solids level of the solution. Consequently, we recommend that these solution parameters be used as indicators of an excursion of leaching solution from the leach field. Our experiments have shown that natural aquifer processes can affect the solution concentration of certain constituents. This effect should be considered when guidelines for aquifer restoration are established.

  5. Aquifer restoration at in-situ leach uranium mines: evidence for natural restoration processes

    International Nuclear Information System (INIS)

    Pacific Northwest Laboratory conducted experiments with aquifer sediments and leaching solution (lixiviant) from an in-situ leach uranium mine. The data from these laboratory experiments and information on the normal distribution of elements associated with roll-front uranium deposits provide evidence that natural processes can enhance restoration of aquifers affected by leach mining. Our experiments show that the concentration of uranium (U) in solution can decrease at least an order of magnitude (from 50 to less than 5 ppM U) due to reactions between the lixiviant and sediment, and that a uranium solid, possibly amorphous uranium dioxide, (UO2), can limit the concentration of uranium in a solution in contact with reduced sediment. The concentrations of As, Se, and Mo in an oxidizing lixiviant should also decrease as a result of redox and precipitation reactions between the solution and sediment. The lixiviant concentrations of major anions (chloride and sulfate) other than carbonate were not affected by short-term (less than one week) contact with the aquifer sediments. This is also true of the total dissolved solids level of the solution. Consequently, we recommend that these solution parameters be used as indicators of an excursion of leaching solution from the leach field. Our experiments have shown that natural aquifer processes can affect the solution concentration of certain constituents. This effect should be considered when guidelines for aquifer restoration are established

  6. MENDING THE IN SITU MANIPULATION BARRIER

    Energy Technology Data Exchange (ETDEWEB)

    PETERSEN, S.W.

    2006-02-06

    In early 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from the DOE Headquarters EM-23 Technical Assistance Program to provide a team of technical experts to develop recommendations for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site in Washington State. To accommodate this request, EM-23 provided support to convene a group of technical experts from industry, a national laboratory, and a DOE site to participate in a 2 1/2-day workshop with the objective of identifying and recommending options to enhance the performance of the 100-D Area reactive barrier and of a planned extension to the northeast. This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)], which resulted from operation of the D/DR Reactors at the Hanford site, was discovered along the Columbia River shoreline and in the 100-D Area. Between 1999 and 2003, a reactive barrier using the In Situ Redox Manipulation (ISRM) technology, was installed a distance of 680 meters along the river to reduce the Cr(VI) in the groundwater. The ISRM technology creates a treatment zone within the aquifer by injection of sodium dithionite, a strong reducing agent that scavenges dissolved oxygen (DO) from the aquifer and reduces ferric iron [Fe(III)], related metals, and oxy-ions. The reduction of Fe(III) to ferrous [Fe(II)] iron provides the primary reduction capacity to reduce Cr(VI) to the +3 state, which is less mobile and less toxic. Bench-scale and field-scale treatability tests were initially conducted to demonstrate proof-of principle and to provide data for estimation of barrier longevity. These calculations estimated barrier longevity in excess of twenty years. However, several years after initial and secondary treatment, groundwater in a number of wells has been found to contain elevated chromium (Cr) concentrations, indicating some loss of reductive capacity within the aquifer. The Technical Assistance Team (TAT) was requested to perform the following activities: (1) evaluate the most probable condition(s) that has led to the presence of Cr(VI) in 12 different barrier wells (i.e. premature loss of reductive capacity), (2) recommend methods for determining the cause of the problem, (3) recommend methods for evaluating the magnitude of the problem, (4) recommend practicable method(s) for mending the barrier that involves a long-term solution, and (5) recommend methods for extending the barrier to the northeast (e.g., changing injection procedure, changing or augmenting the injected material). Since the March 2004 workshop, a decision has been made to place a hold on the barrier extension until more is known about the cause of the problem. However, the report complies with the original request for information on all of the above activities, but focuses on determining the cause of the problem and mending of the existing barrier.

  7. In situ simulation: Taking reported critical incidents and adverse events back to the clinic

    DEFF Research Database (Denmark)

    Juul, Jonas; Paltved, Charlotte

    Introduction In situ simulation offers a novel approach to training in the healthcare setting. It models clinical processes in a real clinical environment and provides the opportunity to correct errors and adjust team interactions without endangering patients. Training in the simulation laboratory does not tap into situational resources, e.g. individual, team, and organisational characteristics such as routines, personal relations, distributed skill-levels etc. Therefore, it fails to fully mimic real clinical team processes. Alternatively, in situ simulation offers a unique opportunity to explore and improve team processes in the clinical environment. Though research on in situ simulation in healthcare is in its infancy, literature is abundant on patient safety, medical simulation, team training and human factors1. Patient safety reporting systems that identify risks to patients can improve patient safety if coupled with training and organisational support2. Insight into the nature of reported critical incidents and adverse events can be used in writing in situ simulation scenarios and thus lead to interventions that enhance patient safety. The patient safety literature emphasises well-developed non-technical skills in preventing medical errors3. Furthermore, critical incidents and adverse events reporting systems comprise a knowledgebase to gain in-depth insights into patient safety issues. This study explores the use of critical incidents and adverse events reports to inform in situ simulation to improve patient safety. Design and purpose The study uses a case study design of in situ simulation training tailored to two emergency departments in the Central Denmark Region. We aim to: - Develop a model that integrates critical incidents and adverse events, a contextual needs analysis and short-term observations in the design of in situ simulation. - Deliver and evaluate the usability of in situ simulation training to interprofessional emergency teams. Methods The project has a triple strategy: 1) Patient safety data analysis and literature review, 2) Video observational study on interprofessional emergency teams, and 3) In situ simulation intervention study with evaluation of training. Reported critical incidents and adverse events will be collected from the Danish Patient Safety Database in the Central Denmark Region and analysed using the qualitative software programme NVivo 10 for content analysis4 and thematic analysis5. Medical experts and simulation faculty will design scenarios for in situ simulation training based on the analysis. Short-term observations using time logs will be performed along with interviews with key informants at the departments. Video data will be collected and used for debriefing6 focusing on team communication and team adaptation7 after in situ simulation training. Perspective and relevance First, this study might help taking reported critical incidents and adverse events back to the clinic. Second, reported critical incidents and adverse events coupled with a contextual needs analysis and short-term observations might aid in scenario design for in situ simulation. This will shed light on how to develop specific learning goals for in situ simulation based on clinical challenges in acute healthcare settings. Third, in situ simulation offers a unique way to study team interactions associated with effective interprofessional teamwork. In particular, team non-technical skills and team adaptation, and their interplay will be scrutinised. In summary, this study offers in situ simulation faculty with a model for integrating reported critical incidents and adverse events with contextual needs analysis and short-term observations. This study generates system knowledge that might lead to changes on the individual, team, and organisational level, and thus enhancing patient safety. References (1) Rosen MA, Hunt EA, Pronovost PJ, Federowicz MA, Weaver SJ. In situ simulation in continuing medical education for the health care professions: A systematic review. J Contin Educ Health Prof 2012; 32(4):243-254.

  8. Oil companies push in-situ recovery

    International Nuclear Information System (INIS)

    Possibly, a third Athabaska tar-sand plant using surface mining will be built in the 1980's, but future development beyond that point will probably depend on in-situ recovery. The discussion of in-situ recovery focusses on the effect it will have on the Canadian chemical industry, for example, the market for sodium hydroxide. To obtain the highest yields of oil from bitumen, an external source of hydrogen is necessary; for example Syncrude imports natural gas to make hydrogen for desulphurization. Gasification of coal is a possible source of hydrogen. Research on hydrocracking is progressing. Use of a prototype CANDU OCR reactor to raise the hot steam necessary for in-situ recovery has been suggested. Venezuela is interested in Canadian upgrading technology. (N.D.H.)

  9. 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.

  10. Osteogenic potential of in situ TiO2 nanowire surfaces formed by thermal oxidation of titanium alloy substrate

    International Nuclear Information System (INIS)

    Highlights: • In situ titanium dioxide (TiO2) nanowire surface structures were fabricated on Ti-6Al-4V substrate using thermal oxidation. • Initial cell adhesion, cell proliferation, cell differentiation, cell mineralization, and osteogenic related gene expression of primary human osteoblasts were examined on the TiO2 nanowire surfaces. • TiO2 nanowire surfaces showed enhanced osteogenic potential as compared to the planar surface. - Abstract: Titanium dioxide (TiO2) nanowire surface structures were fabricated in situ by a thermal oxidation process, and their ability to enhance the osteogenic potential of primary osteoblasts was investigated. Human osteoblasts were isolated from nasal bone and cultured on a TiO2 nanowires coated substrate to assess its in vitro cellular interaction. Bare featureless Ti-6Al-4V substrate was used as a control surface. Initial cell adhesion, cell proliferation, cell differentiation, cell mineralization, and osteogenic related gene expression were examined on the TiO2 nanowire surfaces as compared to the control surfaces after 2 weeks of culturing. Cell adhesion and cell proliferation were assayed by field emission scanning electron microscope (FESEM) and Alamar Blue reduction assay, respectively. The nanowire surfaces promoted better cell adhesion and spreading than the control surface, as well as leading to higher cell proliferation. Our results showed that osteoblasts grown onto the TiO2 nanowire surfaces displayed significantly higher production levels of alkaline phosphatase (ALP), extracellular (ECM) mineralization and genes expression of runt-related transcription factor (Runx2), bone sialoprotein (BSP), ostoepontin (OPN) and osteocalcin (OCN) compared to the control surfaces. This suggests the potential use of such surface modification on Ti-6Al-4V substrates as a promising means to improve the osteointegration of titanium based implants

  11. In situ lyophilisation of nifedipine directly in hard gelatine capsules.

    Science.gov (United States)

    Crum, Matthew; Elkordy, Amal Ali; Zarara, Moataz; Elkordy, Eman Ali

    2013-01-01

    Hydrophobic drugs present a challenge due to: (i) adhesion and agglomeration; hence the choice of the suitable processing technique to have the drugs into orally administered dosage forms is critical. (ii) Poor dissolution and poor aqueous solubility; hence poor bioavailability. A novel method which is in situ lyophilisation directly in hard gelatin capsule shells was used in this research to enhance the dissolution of nifedipine (a model hydrophobic drug) in the presence of co-povidone, Pluronic(®)F-127 and inulin as enhancement excipients (to the best of our knowledge those excipients have not been previously used with nifedipine in lyophilised forms). Solutions of nifedipine and excipients in a range of concentrations (0.5, 1, 5 and 10%w/v) were prepared using a co-solvent system of tert- butyl alcohol/water mixture. These solutions were filled directly into bodies of size 000 hard gelatin capsule shells and freeze dried. Pure drug and all formulations were characterised by solubility, wetting studies and in vitro dissolution. Also, conformational integrity and thermal characteristics of nifedipine formulations were investigated using FT-IR spectroscopy and differential scanning calorimetry (DSC), respectively. The in situ lyophilisation of nifedipine with excipients, looks a promising method not only to improve the hydrophobic drug dissolution but also to be cost effective. PMID:22992055

  12. In situ monitoring of gas emissions

    International Nuclear Information System (INIS)

    Classical extraction apparatuses for gaseous effluents analysis require important maintenance costs. A new in situ system for flue gas monitoring has been developed by the Californian Air Instruments and Measurements Inc. society and installed at the Red Wing refuse-fueled power plant in Minnesota. This system allows the in situ quantitative analysis of carbon monoxide and dioxide effluents using a self calibrating infrared spectrometer. This paper describes the numerous advantages and the maintenance costs reduction provided by this system. (J.S.). 2 photos

  13. In-situ vitrification of waste materials

    Science.gov (United States)

    Powell, James R. (Shoreham, NY); Reich, Morris (Kew Gardens Hills, NY); Barletta, Robert (Wading River, NY)

    1997-11-14

    A method for the in-situ vitrification of waste materials in a disposable can that includes an inner container and an outer container is disclosed. The method includes the steps of adding frit and waste materials to the inner container, removing any excess water, heating the inner container such that the frit and waste materials melt and vitrify after cooling, while maintaining the outer container at a significantly lower temperature than the inner container. The disposable can is then cooled to ambient temperatures and stored. A device for the in-situ vitrification of waste material in a disposable can is also disclosed.

  14. In situ soil remediation using electrokinetics

    International Nuclear Information System (INIS)

    Electrokinetics is emerging as a promising technology for in situ soil remediation. This technique is especially attractive for Superfund sites and government operations which contain large volumes of contaminated soil. The approach uses an applied electric field to induce transport of both radioactive and hazardous waste ions in soil. The transport mechanisms include electroosmosis, electromigration, and electrophoresis. The feasibility of using electrokinetics to move radioactive 137Cs and 60Co at the Hanford Site in Richland, Washington, is discussed. A closed cell is used to provide in situ measurements of 137Cs and 60Co movement in Hanford soil. Preliminary results of ionic movement, along with the corresponding current response, are presented

  15. Osteogenic efficiency of in situ gelling poloxamine systems with and without bone morphogenetic protein-2

    Directory of Open Access Journals (Sweden)

    A Rey-Rico

    2011-04-01

    Full Text Available In situ gelling solutions for minimally invasive local application of bone growth factors are attracting increasing attention as efficient and patient-friendly alternative to bone grafts and solid scaffolds for repairing bone defects. Poloxamines, i.e., X-shaped poly(ethylene oxide-poly(propylene oxide block copolymers with an ethylenediamine core (Tetronic®, were evaluated both as an active osteogenic component and as a vehicle for rhBMP-2 injectable implants. After cytotoxicity screening of various poloxamine varieties, Tetronic 908, 1107, 1301 and 1307 solutions were chosen as the most cytocompatible and their sol-to-gel transitions were rheologically characterized. Viscoelastic gels, formed at 37 ºC, sustained protein release under physiological-like conditions. Formulations of rhBMP-2 led to differentiation of mesenchymal stem cells to osteoblasts, quantified as alkaline phosphatase activity with a maximum at day 7, and to mineralized nodules. Interestingly, poloxamine solely gels led to an initial proliferation of the mesenchymal stem cells (first week, followed by differentiation to osteoblasts (second to third week. Histochemical analysis revealed that Tetronic 908 is only osteoinductive; Tetronic 1107 is mostly osteoinductive, although its use leads to a minor differentiation to adipocytes; Tetronic 1307, solely or loaded with rhBMP-2, causes differentiation of both osteoblasts and adipocytes. Enhanced expression levels of CBFA-1 and collagen type I were observed for Tetronic 908, 1107 and 1307, both solely and combined with rhBMP-2. The intrinsic osteogenic activity of poloxamines (not observed for Pluronic F127 offers novel perspectives for bone regeneration using minimally invasive procedures (i.e., injectable scaffolds and overcoming the safety and the cost/effectiveness concerns associated with large scale clinical use of recombinant growth factors.

  16. In Vivo Osteogenic Differentiation of Human Embryoid Bodies in an Injectable in Situ-Forming Hydrogel

    Directory of Open Access Journals (Sweden)

    Moon Suk Kim

    2013-07-01

    Full Text Available In this study, we examined the in vivo osteogenic differentiation of human embryoid bodies (hEBs by using an injectable in situ-forming hydrogel. A solution containing MPEG-b-(polycaprolactone-ran-polylactide (MCL and hEBs was easily prepared at room temperature. The MCL solution with hEBs and osteogenic factors was injected into nude mice and developed into in situ-forming hydrogels at the injection sites; these hydrogels maintained their shape even after 12 weeks in vivo, thereby indicating that the in situ-forming MCL hydrogel was a suitable scaffold for hEBs. The in vivo osteogenic differentiation was observed only in the in situ gel-forming MCL hydrogel in the presence of hEBs and osteogenic factors. In conclusion, this preliminary study suggests that hEBs and osteogenic factors embedded in an in situ-forming MCL hydrogel may provide numerous benefits as a noninvasive alternative for allogeneic tissue engineering applications.

  17. Carcinoma in situ in the testis

    DEFF Research Database (Denmark)

    Rørth, M; Rajpert-De Meyts, E; Andersson, L; Dieckmann, K P; Fosså, S D; Grigor, K M; Hendry, W F; Herr, H W; Looijenga, L H; Oosterhuis, J W; Skakkebaek, N E

    2000-01-01

    Carcinoma in situ (CIS) of the testis is a common precursor of germ-cell tumours in adults and adolescents, with the exception of spermatocytic seminoma. This article reviews existing knowledge on the pathobiology, genetic aspects and epidemiology of CIS, discusses current hypotheses concerning pathogenesis and invasive progression of germ-cell neoplasms and provides guidelines for diagnosis and clinical management of CIS.

  18. Design Games for In-Situ Design

    DEFF Research Database (Denmark)

    Kristiansen, Erik

    2013-01-01

    The mobile culture has spawned a host of context-based products, like location-based and tag-based applications. This presents a new challenge for the designer. There is a need of design methods that acknowledge the context and allows it to influence the design ideas. This article focuses on a design problem where an in-situ design practice may further the early design process: the case of designing a pervasive game. Pervasive games are computer games, played using the city as a game board and often using mobile phones with GPS. Some contextual design methods exist, but the author proposes an approach that calls for the designer to conceptualise and perform ideas in-situ, that is on the site, where the game is supposed to be played. The problem was to design a creativity method that incorporated in-situ design work and which generated game concepts for pervasive games. The proposed design method, called sitestorming, is based on a game using Situationistic individual exploration of the site and different types of game cards, followed by a joint evaluation of the generated ideas. A series of evaluations showed that the designers found the method enjoyable to use, that the method motivated idea generation, and that using in-situ design influenced their design ideas.

  19. Parametric melting studies for in situ vitrification

    International Nuclear Information System (INIS)

    This report describes a series of simulation studies which examine heat conduction and electric heating during in situ vitrification (ISV). The simulation studies determine the effects of soil parameter changes on the ISV process. Changes in heat capacity, thermal conductivity and electrical conductivity are considered. The results of these studies provide a basis for experimental measurement accuracy requirements

  20. The determination of the in situ structure by nuclear spin contrast variation

    Energy Technology Data Exchange (ETDEWEB)

    Stuhrmann, H.B. [GKSS Forschungszentrum, Geesthacht (Germany); Nierhaus, K.H. [Max-Planch-Institut fuer Molekulare Genetik, Berlin (Germany)

    1994-12-31

    Polarized neutron scattering from polarized nuclear spins in hydrogenous substances opens a new way of contrast variation. The enhanced contrast due to proton spin polarization was used for the in situ structure determination of tRNA of the functional complex of the E.coli ribosome.

  1. The determination of the in situ structure by nuclear spin contrast variation

    International Nuclear Information System (INIS)

    Polarized neutron scattering from polarized nuclear spins in hydrogenous substances opens a new way of contrast variation. The enhanced contrast due to proton spin polarization was used for the in situ structure determination of tRNA of the functional complex of the E.coli ribosome

  2. In Situ Cleanable Alternative HEPA Filter Media

    International Nuclear Information System (INIS)

    The Westinghouse Savannah River Company, located at the Savannah River Site in Aiken, South Carolina, is currently testing two types of filter media for possible deployment as in situ regenerable/cleanable High Efficiency Particulate Air (HEPA) filters. The filters are being investigated to replace conventional, disposable, glass-fiber, HEPA filters that require frequent removal, replacement, and disposal. This is not only costly and subjects site personnel to radiation exposure, but adds to the ever-growing waste disposal problem. The types of filter media being tested, as part of a National Energy Technology Laboratory procurement, are sintered nickel metal and ceramic monolith membrane. These media were subjected to a hostile environment to simulate conditions that challenge the high-level waste tank ventilation systems. The environment promoted rapid filter plugging to maximize the number of filter loading/cleaning cycles that would occur in a specified period of time. The filters were challenged using nonradioactive simulated high-level waste materials and atmospheric dust; materials that cause filter pluggage in the field. The filters are cleaned in situ using an aqueous solution. The study found that both filter media were insensitive to high humidity or moisture conditions and were easily cleaned in situ. The filters regenerated to approximately clean filter status even after numerous plugging and in situ cleaning cycles. Air Techniques International is conducting particle retention testing on the filter media at the Oak Ridge Filter Test Facility. The filters are challenged using 0.3-mm di-octyl phthalate particles. Both the ceramic and sintered media have a particle retention efficiency > 99.97%. The sintered metal and ceramic filters not only can be cleaned in situ, but also hold great potential as a long life alternative to conventional HEPA filters. The Defense Nuclear Facility Safety Board Technical Report, ''HEPA Filters Used in the Department of Energy's Hazardous Facilities'', found that conventional glass fiber HEPA filters are structurally weak and easily damaged by water or fire. The structurally stronger sintered metal and ceramic filters would reduce the potential of a catastrophic HEPA filter failure due to filter media breakthrough in the process ventilation system. An in situ regenerable system may also find application in recovering nuclear materials, such as plutonium, collected on glove box exhaust HEPA filters. This innovative approach of the in situ regenerative filtration system may be a significant improvement upon the shortfalls of conventional disposable HEPA filters

  3. In Situ Remediation Integrated Program: Technology summary

    International Nuclear Information System (INIS)

    The In Situ Remediation Integrated Program (ISR IP) was instituted out of recognition that in situ remediation could fulfill three important criteria: significant cost reduction of cleanup by eliminating or minimizing excavation, transportation, and disposal of wastes; reduced health impacts on workers and the public by minimizing exposure to wastes during excavation and processing; and remediation of inaccessible sites, including: deep subsurfaces, in, under, and around buildings. Buried waste, contaminated soils and groundwater, and containerized wastes are all candidates for in situ remediation. Contaminants include radioactive wastes, volatile and non-volatile organics, heavy metals, nitrates, and explosive materials. The ISR IP intends to facilitate development of in situ remediation technologies for hazardous, radioactive, and mixed wastes in soils, groundwater, and storage tanks. Near-term focus is on containment of the wastes, with treatment receiving greater effort in future years. ISR IP is an applied research and development program broadly addressing known DOE environmental restoration needs. Analysis of a sample of 334 representative sites by the Office of Environmental Restoration has shown how many sites are amenable to in situ remediation: containment--243 sites; manipulation--244 sites; bioremediation--154 sites; and physical/chemical methods--236 sites. This needs assessment is focused on near-term restoration problems (FY93--FY99). Many other remediations will be required in the next century. The major focus of the ISR EP is on the long term development of permanent solutions to these problems. Current needs for interim actions to protect human health and the environment are also being addressed

  4. In-Situ Nitrogen Doping of the TiO2 Photocatalyst Deposited by PEALD for Visible Light Activity

    International Nuclear Information System (INIS)

    In this paper, an N-doped titanium oxide (TiO2) photocatalyst is deposited by a plasma-enhanced atomic layer deposition (PEALD) system through the in-situ doping method. X-ray photoelectron spectroscopy (XPS) analysis indicates that substitutional nitrogen atoms (?395.9 eV) with 1 atom% are effectively doped into TiO2 films. UV-VIS spectrometry shows that the in-situ nitrogen doping method indeed enhances the visible-activity of TiO2 films in the 425–550 nm range, and the results of the performance tests of the N-doped TiO2 films also imply that the photocatalysis activity is improved by in-situ doping. The in-situ doping mechanism of the N-doped TiO2 film is suggested according to the XPS results and the typical atomic layer deposition process

  5. In situ salinity measurements in seawater with a fibre-optic probe

    OpenAIRE

    Diaz Herrera, N; Esteban, O; Navarrete, M.; Le Haitre, Michel; Gonzalez Cano, A

    2006-01-01

    We have successfully proved the feasibility of an optical salinity meter for marine applications in a two week measurement campaign, carried out for the realization of in situ salinity measurements in seawater. An optical instrument (optode), in which the main element is a fibre-optic refractive-index sensor based on surface plasmon resonance (SPR), has been developed for that purpose, and has been especially designed to be able to operate in realistic conditions. The performance of the optod...

  6. Fluoroscence in situ hybridization of chicken intestinal samples with bacterial rRNA targeted oligonucleotide probes

    DEFF Research Database (Denmark)

    Olsen, Katja Nyholm; Francesch, M.; Christensen, Henrik

    2006-01-01

    The objective was to develop a fast and accurate molecular method for the quantification of the intestinal flora in chickens by rRNA fluorescence in situ hybridization (FISH). Seven weeks old conventionally reared Lohmann hens were used to set up the method. To sample ileal intestinal content, the distal part from Meckels diverticulum to the ileo-caecal junction was removed. Fixation was performed in ethanol and phosphate buffered saline. After washing by centrifugation, the sample was resuspend...

  7. Late post-traumatic flap dislocation and macrostriae after laser in situ keratomileusis

    OpenAIRE

    Sinha, Rajesh; Shekhar, Himanshu; Tinwala, Sana; Gangar, Anita; Titiyal, Jeewan S.

    2014-01-01

    We report an unusual flap-related complication that occurred 4 years after uneventful laser in situ keratomileusis (LASIK) performed in the eye of a 20-year-old woman. She developed dislocation with partial infolding of the LASIK flap with macrostriae and epithelial ingrowth in her left eye after trauma by a wooden chip. The flap was refloated, stretched, smoothened, and hydrated on both under and outer surfaces after epithelial debridement. At 1 week, the uncorrected visual acuity was 20/20 ...

  8. The production and degradation of trichloroacetic acid in soil: Results from in situ soil column experiments

    OpenAIRE

    Heal, M. R.; Dickey, C.A.; Heal, K.V.; Stidson, R T; Matucha, M.; Cape, J. N.

    2010-01-01

    Previous work has indicated that the soil is important to understanding biogeochemical fluxes of trichloroacetic acid (TCA) in the rural environment, in forests in particular. Here, the hydrological and TCA fluxes through 22 in situ soil columns in a forest and moorland-covered catchment and an agricultural grassland field in Scotland were monitored every 2 weeks for several months either as controls or in TCA manipulation (artificial dosing) experiments. This was supplemented by laboratory e...

  9. In situ measurements of volatile organic compounds in a boreal forest

    OpenAIRE

    Hakola, H.; Hellén, H.; Henriksson, M.; Rinne, J.; Kulmala, M

    2012-01-01

    We present biogenic VOC, including sesquiterpenes, measurements at the SMEAR II station (Station For Measuring Forest Ecosystem-Atmosphere Relations) in Finland using an in situ gas chromatograph mass-spectrometer with 2 h time resolution. The measurements were conducted over the period October 2010–October 2011, at least one week every month. To our knowledge there are no earlier species-speciated semi-continuous BVOC data also covering dormant periods.

    During th...

  10. In-Situ Remediation Approaches for the Management of Contaminated Sites: A Comprehensive Overview.

    Science.gov (United States)

    Kuppusamy, Saranya; Palanisami, Thavamani; Megharaj, Mallavarapu; Venkateswarlu, Kadiyala; Naidu, Ravi

    2016-01-01

    Though several in-situ treatment methods exist to remediate polluted sites, selecting an appropriate site-specific remediation technology is challenging and is critical for successful clean up of polluted sites. Hence, a comprehensive overview of all the available remediation technologies to date is necessary to choose the right technology for an anticipated pollutant. This review has critically evaluated the (i) technological profile of existing in-situ remediation approaches for priority and emerging pollutants, (ii) recent innovative technologies for on-site pollutant remediation, and (iii) current challenges as well as future prospects for developing innovative approaches to enhance the efficacy of remediation at contaminated sites. PMID:26423073

  11. The in situ tumour response to combinations of cyclophosphamide and tirapazamine.

    OpenAIRE

    Siemann, D W

    1996-01-01

    The potential of tirapazamine to enhance the in situ efficacy of the anti-cancer drug cyclophosphamide (CP) was evaluated in two rodent tumours (KHT sarcoma, 16C mammary carcinoma) and one human ovarian tumour xenograft (MLS) using end points of in vivo to in vitro cell survival or in situ tumour growth delay. For comparison, bone marrow toxicity under similar treatment conditions was determined using a CFU-GM stem cell survival assay. The results showed that a 0.27 mmol kg-1 dose of tirapaza...

  12. New in situ crosslinking chemistries for hydrogelation

    Science.gov (United States)

    Roberts, Meredith Colleen

    Over the last half century, hydrogels have found immense value as biomaterials in a vast number of biomedical and pharmaceutical applications. One subset of hydrogels receiving increased attention is in situ forming gels. Gelling by either bioresponsive self-assembly or mixing of binary crosslinking systems, these technologies are useful in minimally invasive applications as well as drug delivery systems in which the sol-to-gel transition aids the formulation's performance. Thus far, the field of in situ crosslinking hydrogels has received limited attention in the development of new crosslinking chemistries. Moreover, not only does the chemical nature of the crosslinking moieties allow these systems to perform in situ, but they contribute dramatically to the mechanical properties of the hydrogel networks. For example, reversible crosslinks with finite lifetimes generate dynamic viscoelastic gels with time-dependent properties, whereas irreversible crosslinks form highly elastic networks. The aim of this dissertation is to explore two new covalent chemistries for their ability to crosslink hydrogels in situ under physiological conditions. First, reversible phenylboronate-salicylhydroxamate crosslinking was implemented in a binary, multivalent polymeric system. These gels formed rapidly and generated hydrogel networks with frequency-dependent dynamic rheological properties. Analysis of the composition-structure-property relationships of these hydrogels---specifically considering the effects of pH, degree of polymer functionality, charge of the polymer backbone and polymer concentration on dynamic theological properties---was performed. These gels demonstrate diverse mechanical properties, due to adjustments in the binding equilibrium of the pH-sensitive crosslinks, and thus have the potential to perform in a range of dynamic or bioresponsive applications. Second, irreversible catalyst-free "click" chemistry was employed in the hydrogelation of multivalent azide-functionalized polymers with divalent electron-deficient alkyne crosslinkers. Elastic hydrogels formed at physiological temperature; however the gelation kinetics was found to be too slow for effective performance in most in situ crosslinking hydrogel applications. Therefore, a small molecule kinetics study using model crosslinking moieties was performed to evaluate the ability to expedite gelation via compositional changes in the alkyne dipolarophile. With further synthetic development, this crosslinking chemistry is likely to be useful in a number of applications requiring the formation of permanent, elastic networks in situ.

  13. Software Tools for In-Situ Documentation of Built Heritage

    Science.gov (United States)

    Smars, P.

    2013-07-01

    The paper presents open source software tools developed by the author to facilitate in-situ documentation of architectural and archæological heritage. The design choices are exposed and related to a general issue in conservation and documentation: taking decisions about a valuable object under threat . The questions of level of objectivity is central to the three steps of this process. It is our belief that in-situ documentation has to be favoured in this demanding context, full of potential discoveries. The very powerful surveying techniques in rapid development nowadays enhance our vision but often tend to bring back a critical part of the documentation process to the office. The software presented facilitate a direct treatment of the data on the site. Emphasis is given to flexibility, interoperability and simplicity. Key features of the software are listed and illustrated with examples (3D model of Gothic vaults, analysis of the shape of a column, deformation of a wall, direct interaction with AutoCAD).

  14. Spontaneous heterotopic pregnancy causing tubal rupture in a patient with intrauterine device in-situ

    Directory of Open Access Journals (Sweden)

    Serpil Telci

    2014-01-01

    Full Text Available Spontaneous heterotopic pregnancy (HP is a rare but life threatening condition. A case of 27 years old patient who admitted to our emergency gynecology clinic for acute abdominal pain is presented. The transvaginal ultrasound revealed two embryos with cardiac activity; one intrauterine (8 week and 3 day , and the other one in the left adnexa (7 week and 3 day and an intrauterine device (IUD in situ. The patient had left salpingectomy with laparotomy and after the fifth hour of operation she had spontaneous abortion of intrauterine pregnancy. We reported a case of heterotopic pregnancy and relation with IUD and a brief review of the literature.

  15. The in situ combustion pilot project in Bare field, Orinoco oil belt, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Perozo, H.A.; Mendoza, A.J.; Teixeira, J.; Alvarez, A.; Vasquez, P. [PDVSA Intevep (Venezuela)

    2011-07-01

    In heavy oil fields, in-situ combustion technology can be used as a means to enhance oil recovery. This process consists of burning some part of the oil present in the reservoir to produce heat that allow increased oil displacement. The aim of this study is to present an in situ combustion pilot project (ISCPP). This project will be conducted by PDVSA Intevep and its partners in the Orinoco oil belt, Venezuela, to assess the effect of in situ combustion in increasing recovery factors from heavy crude oil reservoirs. The laboratory combustion test analyses, the static and dynamic reservoir simulations, the design, construction and completion of all wells and the study, analysis and development of surface facilities are discussed. The ISCPP is expected to be running by the end of 2011.

  16. Liquid crystalline polymer nanocomposites reinforced with in-situ reduced graphene oxide

    Directory of Open Access Journals (Sweden)

    D. Pedrazzoli

    2015-08-01

    Full Text Available In this work liquid-crystalline polymer (LCP nanocomposites reinforced with in-situ reduced graphene oxide are investigated. Graphene oxide (GO was first synthesized by the Hummers method, and the kinetics of its thermal reduction was assessed. GO layers were then homogeneously dispersed in a thermotropic liquid crystalline polymer matrix (Vectran®, and an in-situ thermal reduction of GO into reduced graphene oxide (rGO was performed. Even at low rGO amount, the resulting nanocomposites exhibited an enhancement of both the mechanical properties and the thermal stability. Improvements of the creep stability and of the thermo-mechanical behavior were also observed upon nanofiller incorporation. Furthermore, in-situ thermal reduction of the insulating GO into the more electrically conductive rGO led to an important surface resistivity decrease in the nanofilled samples.

  17. In situ Raman spectroscopy for growth monitoring of vertically aligned multiwall carbon nanotubes in plasma reactor

    International Nuclear Information System (INIS)

    Portable and highly sensitive Raman setup was associated with a plasma-enhanced chemical vapor deposition reactor enabling in situ growth monitoring of multi-wall carbon nanotubes despite the combination of huge working distance, high growth speed and process temperature and reactive plasma condition. Near Edge X-ray absorption fine structure spectroscopy was used for ex situ sample analysis as a complementary method to in situ Raman spectroscopy. The results confirmed the fact that the “alternating” method developed here can accurately be used for in situ Raman monitoring under reactive plasma condition. The original analytic tool can be of great importance to monitor the characteristics of these nanostructured materials and readily define the ultimate conditions for targeted results

  18. In situ remediation of uranium contaminated groundwater

    International Nuclear Information System (INIS)

    In an effort to develop cost-efficient techniques for remediating uranium contaminated groundwater at DOE Uranium Mill Tailing Remedial Action (UMTRA) sites nationwide, Sandia National Laboratories (SNL) deployed a pilot scale research project at an UMTRA site in Durango, CO. Implementation included design, construction, and subsequent monitoring of an in situ passive reactive barrier to remove Uranium from the tailings pile effluent. A reactive subsurface barrier is produced by emplacing a reactant material (in this experiment - various forms of metallic iron) in the flow path of the contaminated groundwater. Conceptually the iron media reduces and/or adsorbs uranium in situ to acceptable regulatory levels. In addition, other metals such as Se, Mo, and As have been removed by the reductive/adsorptive process. The primary objective of the experiment was to eliminate the need for surface treatment of tailing pile effluent. Experimental design, and laboratory and field preliminary results are discussed with regard to other potential contaminated groundwater treatment applications

  19. In-Situ Planetary Chemical Analysis

    Science.gov (United States)

    Kounaves, S. P.; Buehler, M. G.; Grannan, S. M.; Hecht, M. H.; Kuhlman, K. R.

    2000-01-01

    Both, the search for evidence of life on Mars and the assessment of the Martian environment in respect to its compatibility with human explorers, will require the ability to measure and understand the aqueous chemistry of the Martian regolith. Direct in-situ chemical analysis is the only method by which chemical biosignatures can be reliably recognized and the toxicity of the regolith accurately assessed. Qualitative and quantitative determination of the aqueous ionic constituents and their concentrations is critical in developing kinetic and thermodynamic models that can be used to accurately predict the potential of the past or present Martian geochemical environment to have either generated or still sustain life. In-situ chemical characterization could provide evidence as to whether the chemical composition of the regolith or evaporates in suspected ancient water bodies have been biologically influenced.

  20. In situ SU-8 silver nanocomposites

    DEFF Research Database (Denmark)

    Fischer, Søren Vang; Uthuppu, Basil; Jakobsen, Mogens Havsteen

    2015-01-01

    Nanocomposite materials containing metal nanoparticles are of considerable interest in photonics and optoelectronics applications. However, device fabrication of such materials always encounters the challenge of incorporation of preformed nanoparticles into photoresist materials. As a solution to this problem, an easy new method of fabricating silver nanocomposites by an in situ reduction of precursors within the epoxy-based photoresist SU-8 has been developed. AgNO3 dissolved in acetonitrile an...

  1. In Situ TEM Creation of Nanowire Devices

    DEFF Research Database (Denmark)

    Alam, Sardar Bilal

    2015-01-01

    Integration of silicon nanowires (SiNWs) as active components in devices requires that desired mechanical, thermal and electrical interfaces can be established between the nanoscale geometry of the SiNW and the microscale architecture of the device. In situ transmission electron microscopy (TEM), which has proved to be a powerful method for visualizing the physical processes involved in the growth of nanowires by the vapour liquid solid (VLS) mechanism, was used to study VLS SiNW contact formati...

  2. In situ vitrification of buried waste

    International Nuclear Information System (INIS)

    This report describes the application of the in situ vitrification (ISV) process to buried mixed and transuranic wastes. The results of product evaluation activities from two ISV intermediate-scale field tests conducted on simulated buried waste pits are reported. The physical properties and durability of the resulting waste form is discussed. The resulting waste form was found to be more leach resistant than high-level nuclear waste glasses and to be very comparable to stable natural materials, such as obsidian. (author)

  3. In situ macromolecular crystallography using microbeams.

    OpenAIRE

    Axford, D; Owen, RL; Aishima, J; Foadi, J; Morgan, AW; Robinson, JI; Nettleship, JE; Owens, RJ; Moraes, I; Fry, EE; Grimes, JM; Harlos, K; Kotecha, A.; Ren, J; Sutton, G.

    2012-01-01

    Despite significant progress in high-throughput methods in macromolecular crystallography, the production of diffraction-quality crystals remains a major bottleneck. By recording diffraction in situ from crystals in their crystallization plates at room temperature, a number of problems associated with crystal handling and cryoprotection can be side-stepped. Using a dedicated goniometer installed on the microfocus macromolecular crystallography beamline I24 at Diamond Light Source, crystals ha...

  4. PREPARATION OF NANOCOMPOSITES BY IN SITU POLIMERIZATION

    OpenAIRE

    PAULA ZAPATA; RAÚL QUIJADA; JAIME RETUER; EDWIN MONCADA

    2008-01-01

    Polyethylene nanocomposites were obtained by in situ polymerization using both montmorillonite (natural clay) and montmorillonite organically modified with octadecylamine (O-Clo). In this proposed methodology the clays were added directly in the reactor together with the catalytic system (metallocene catalyst and methylaluminoxane) and ethylene. The nanocomposites were characterized by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and t...

  5. Autonomous in situ measurements of seawater alkalinity.

    Science.gov (United States)

    Spaulding, Reggie S; DeGrandpre, Michael D; Beck, James C; Hart, Robert D; Peterson, Brittany; De Carlo, Eric H; Drupp, Patrick S; Hammar, Terry R

    2014-08-19

    Total alkalinity (AT) is an important parameter for describing the marine inorganic carbon system and understanding the effects of atmospheric CO2 on the oceans. Measurements of AT are limited, however, because of the laborious process of collecting and analyzing samples. In this work we evaluate the performance of an autonomous instrument for high temporal resolution measurements of seawater AT. The Submersible Autonomous Moored Instrument for alkalinity (SAMI-alk) uses a novel tracer monitored titration method where a colorimetric pH indicator quantifies both pH and relative volumes of sample and titrant, circumventing the need for gravimetric or volumetric measurements. The SAMI-alk performance was validated in the laboratory and in situ during two field studies. Overall in situ accuracy was -2.2 ± 13.1 ?mol kg(-1) (n = 86), on the basis of comparison to discrete samples. Precision on duplicate analyses of a carbonate standard was ±4.7 ?mol kg(-1) (n = 22). This prototype instrument can measure in situ AT hourly for one month, limited by consumption of reagent and standard solutions. PMID:25051401

  6. A Novel in situ Trigger Combination Method

    International Nuclear Information System (INIS)

    Searches for rare physics processes using particle detectors in high-luminosity colliding hadronic beam environments require the use of multi-level trigger systems to reject colossal background rates in real time. In analyses like the search for the Higgs boson, there is a need to maximize the signal acceptance by combining multiple different trigger chains when forming the offline data sample. In such statistically limited searches, datasets are often amassed over periods of several years, during which the trigger characteristics evolve and their performance can vary significantly. Reliable production cross-section measurements and upper limits must take into account a detailed understanding of the effective trigger inefficiency for every selected candidate event. We present as an example the complex situation of three trigger chains, based on missing energy and jet energy, to be combined in the context of the search for the Higgs (H) boson produced in association with a W boson at the Collider Detector at Fermilab (CDF). We briefly review the existing techniques for combining triggers, namely the inclusion, division, and exclusion methods. We introduce and describe a novel fourth in situ method whereby, for each candidate event, only the trigger chain with the highest a priori probability of selecting the event is considered. The in situ combination method has advantages of scalability to large numbers of differing trigger chains and of insensitivity to correlations between triggers. We compare the inclusion and in situ methods for signal event yields in the CDF WH search.

  7. IN SITU FIELD TESTING OF PROCESSES

    International Nuclear Information System (INIS)

    The purpose of this scientific analysis report is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts and surface-based boreholes through unsaturated zone (UZ) tuff rock units. In situ testing, monitoring, and associated laboratory studies are conducted to directly assess and evaluate the waste emplacement environment and the natural barriers to radionuclide transport at Yucca Mountain. This scientific analysis report supports and provides data to UZ flow and transport model reports, which in turn contribute to the Total System Performance Assessment (TSPA) of Yucca Mountain, an important document for the license application (LA). The objectives of ambient field-testing activities are described in Section 1.1. This report is the third revision (REV 03), which supercedes2. The scientific analysis of data for inputs to model calibration and validation as documented in2 were developed in accordance with the Technical Work Plan (TWP) ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (BSC 2004 [DIRS 167969]). This revision was developed in accordance with the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.4) for better integrated, consistent, transparent, traceable, and more complete documentation in this scientific analysis report and associated UZ flow and transport model reports. No additional testing or analyses were performed as part of this revision. The list of relevant acceptance criteria is provided by ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654]), Table 3-1. Additional deviations from the TWP regarding the features, events, and processes (FEPs) list are discussed in Section 1.3. Documentation in this report includes descriptions of how, and under what conditions, the tests were conducted. The descriptions and analyses provide data useful for refining and confirming the understanding of flow, drift seepage, and transport processes in the UZ. The UZ testing activities included measurement of permeability distribution, quantification of the seepage of water into the drifts, evaluation of fracture-matrix interaction, study of flow along faults, testing of flow and transport between drifts, characterization of hydrologic heterogeneity along drifts, estimation of drying effects on the rock surrounding the drifts due to ventilation, monitoring of moisture conditions in open and sealed drifts, and determination of the degree of minimum construction water migration below drift. These field tests were conducted in two underground drifts at Yucca Mountain, the Exploratory Studies Facility (ESF) drift, and the cross-drift for Enhanced Characterization of the Repository Block (ECRB), as described in Section 1.2. Samples collected in boreholes and underground drifts have been used for additional hydrochemical and isotopic analyses for additional understanding of the UZ setting. The UZ transport tests conducted at the nearby Busted Butte site (see Figure 1-4) are also described in this scientific analysis report

  8. IN SITU FIELD TESTING OF PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    J.S.Y. YANG

    2004-11-08

    The purpose of this scientific analysis report is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts and surface-based boreholes through unsaturated zone (UZ) tuff rock units. In situ testing, monitoring, and associated laboratory studies are conducted to directly assess and evaluate the waste emplacement environment and the natural barriers to radionuclide transport at Yucca Mountain. This scientific analysis report supports and provides data to UZ flow and transport model reports, which in turn contribute to the Total System Performance Assessment (TSPA) of Yucca Mountain, an important document for the license application (LA). The objectives of ambient field-testing activities are described in Section 1.1. This report is the third revision (REV 03), which supercedes REV 02. The scientific analysis of data for inputs to model calibration and validation as documented in REV 02 were developed in accordance with the Technical Work Plan (TWP) ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (BSC 2004 [DIRS 167969]). This revision was developed in accordance with the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.4) for better integrated, consistent, transparent, traceable, and more complete documentation in this scientific analysis report and associated UZ flow and transport model reports. No additional testing or analyses were performed as part of this revision. The list of relevant acceptance criteria is provided by ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654]), Table 3-1. Additional deviations from the TWP regarding the features, events, and processes (FEPs) list are discussed in Section 1.3. Documentation in this report includes descriptions of how, and under what conditions, the tests were conducted. The descriptions and analyses provide data useful for refining and confirming the understanding of flow, drift seepage, and transport processes in the UZ. The UZ testing activities included measurement of permeability distribution, quantification of the seepage of water into the drifts, evaluation of fracture-matrix interaction, study of flow along faults, testing of flow and transport between drifts, characterization of hydrologic heterogeneity along drifts, estimation of drying effects on the rock surrounding the drifts due to ventilation, monitoring of moisture conditions in open and sealed drifts, and determination of the degree of minimum construction water migration below drift. These field tests were conducted in two underground drifts at Yucca Mountain, the Exploratory Studies Facility (ESF) drift, and the cross-drift for Enhanced Characterization of the Repository Block (ECRB), as described in Section 1.2. Samples collected in boreholes and underground drifts have been used for additional hydrochemical and isotopic analyses for additional understanding of the UZ setting. The UZ transport tests conducted at the nearby Busted Butte site (see Figure 1-4) are also described in this scientific analysis report.

  9. In vivo endothelization of tubular vascular grafts through in situ recruitment of endothelial and endothelial progenitor cells by RGD-fused mussel adhesive proteins.

    Science.gov (United States)

    Kang, Tae-Yun; Lee, Jung Ho; Kim, Bum Jin; Kang, Jo-A; Hong, Jung Min; Kim, Byoung Soo; Cha, Hyung Joon; Rhie, Jong-Won; Cho, Dong-Woo

    2015-01-01

    The use of tissue mimics in vivo, including patterned vascular networks, is expected to facilitate the regeneration of functional tissues and organs with large volumes. Maintaining patency of channels in contact with blood is an important issue in the development of a functional vascular network. Endothelium is the only known completely non-thrombogenic material; however, results from treatments to induce endothelialization are inconclusive. The present study was designed to evaluate the clinical applicability of in situ recruitment of endothelial cells/endothelial progenitor cells (EC/EPC) and pre-endothelization using a recombinant mussel adhesive protein fused with arginine-glycine-aspartic acid peptide (MAP-RGD) coating in a model of vascular graft implantation. Microporous polycaprolactone (PCL) scaffolds were fabricated with salt leaching methods and their surfaces were modified with collagen and MAP-RGD. We then evaluated their anti-thrombogenicity with an in vitro hemocompatibility assessment and a 4-week implantation in the rabbit carotid artery. We observed that MAP-RGD coating reduced the possibility of early in vivo graft failure and enhanced re-endothelization by in situ recruitment of EC/EPC (patency rate: 2/3), while endothelization prior to implantation aggravated the formation of thrombosis and/or IH (patency rate: 0/3). The results demonstrated that in situ recruitment of EC/EPC by MAP-RGD could be a promising strategy for vascular applications. In addition, it rules out several issues associated with pre-endothelization, such as cell source, purity, functional modulation and contamination. Further evaluation of long term performance and angiogenesis from the luminal surface may lead to the clinical use of MAP-RGD for tubular vascular grafts and regeneration of large-volume tissues with functional vascular networks. PMID:25599716

  10. In situ laser processing in a scanning electron microscope

    International Nuclear Information System (INIS)

    Laser delivery probes using multimode fiber optic delivery and bulk focusing optics have been constructed and used for performing materials processing experiments within scanning electron microscope/focused ion beam instruments. Controlling the current driving a 915-nm semiconductor diode laser module enables continuous or pulsed operation down to sub-microsecond durations, and with spot sizes on the order of 50 ?m diameter, achieving irradiances at a sample surface exceeding 1 MW/cm2. Localized laser heating has been used to demonstrate laser chemical vapor deposition of Pt, surface melting of silicon, enhanced purity, and resistivity via laser annealing of Au deposits formed by electron beam induced deposition, and in situ secondary electron imaging of laser induced dewetting of Au metal films on SiOx.

  11. In situ reacted rare-earth hexaaluminate interphases

    International Nuclear Information System (INIS)

    A novel in situ reaction between a ceria-doped zirconia interphase coating on Saphikon fibers and an outer alumina coating has resulted in the formation of oriented hexaaluminate platelets which can act as a low fracture energy interface barrier for crack deflection in oxide-oxide ceramic-matrix composites (CMCs). The reaction proceeds only in reducing environments where the reduction of the cerium and zirconium ions to their 3+ valent state causes a destabilization phenomenon consistent with previously reported findings. The diffusion of the cerium from the zirconia into solid solution with the alumina can stabilize the layered hexaaluminate structure. Preferred orientational growth of the hexaaluminate parallel to the coating interface was observed which is the required orientation for enhanced debonding at the fiber/matrix interface in long-fiber-reinforced CMCs

  12. Aluminum induced in situ crystallization of amorphous SiC

    Science.gov (United States)

    Wang, Li; Dimitrijev, Sima; Tanner, Philip; Zou, Jin

    2009-05-01

    Experimental evidence of aluminum induced in situ crystallization of amorphous SiC is presented. The deposition of SiC films on Si substrates was performed using low pressure chemical vapor deposition method at 600 °C with concurrent supply of Al(CH3)3 and H3SiCH3. Transmission electron micrographs confirm the presence of nanocrystals, whereas capacitance-voltage measurements demonstrate that the deposited films are p type doped. A crystallization mechanism is proposed based on the classic theory of nucleation in the growth rate limited regime. The introduction of Al(CH3)3 enhances the surface reaction and increases the supersaturation, which reduces the activation energy for nucleation.

  13. Air-coupled acoustic thermography for in-situ evaluation

    Science.gov (United States)

    Zalameda, Joseph N. (Inventor); Winfree, William P. (Inventor); Yost, William T. (Inventor)

    2010-01-01

    Acoustic thermography uses a housing configured for thermal, acoustic and infrared radiation shielding. For in-situ applications, the housing has an open side adapted to be sealingly coupled to a surface region of a structure such that an enclosed chamber filled with air is defined. One or more acoustic sources are positioned to direct acoustic waves through the air in the enclosed chamber and towards the surface region. To activate and control each acoustic source, a pulsed signal is applied thereto. An infrared imager focused on the surface region detects a thermal image of the surface region. A data capture device records the thermal image in synchronicity with each pulse of the pulsed signal such that a time series of thermal images is generated. For enhanced sensitivity and/or repeatability, sound and/or vibrations at the surface region can be used in feedback control of the pulsed signal applied to the acoustic sources.

  14. In Situ TEM Creation of Nanowire Devices

    DEFF Research Database (Denmark)

    Alam, Sardar Bilal

    2015-01-01

    Integration of silicon nanowires (SiNWs) as active components in devices requires that desired mechanical, thermal and electrical interfaces can be established between the nanoscale geometry of the SiNW and the microscale architecture of the device. In situ transmission electron microscopy (TEM), which has proved to be a powerful method for visualizing the physical processes involved in the growth of nanowires by the vapour liquid solid (VLS) mechanism, was used to study VLS SiNW contact formation process. Electrical characteristics and effects of surface modification on electrical behavior of SiNW were also investigated in situ. SiNWs were grown on silicon microcantilever heaters using the VLS mechanism. When grown across a gap between adjacent cantilevers, contact was formed when the SiNW impinged on the sidewall of an adjacent cantilever. Using in situ TEM, SiNW contact formation process at high temperatures was observed in real time. As the eutectic droplet made contact, it wetted the surface; Si growth catalyzed by the eutectic continued, while at the same time Au often migrated/diffused away from the contact site. The parameters of this contact formation process were measured from movies recorded during contact events. It is demonstrated that the geometry of the final contact formed between the nanowire and the silicon surface could be controlled by varying the contact surface temperature and the electrical current through the bridging SiNW. By adjusting the contact surface temperature and nanowire current, the balance of Si deposition vs. Au migration could be controlled. This gave rise to a variety of contact geometries including a Si to Si contact with controlled shape and diameter, a nano gap, or a Si-Au-Si contact. It is further demonstrated that electromigration is the best candidate for controlling catalyst migration. Kinetics of the contact formation process was studied in detail and the conditions which resulted in different contact geometries are explained. On completion of the contact, SiNW bridging the adjacent cantilevers was electrically connected at its two ends, base and tip and its electrical properties were probed in situ TEM. Such SiNW bridges clamped between two cantilevers in situ TEM was an interesting platform for studying the effect of surface modification on SiNWs electrical properties. The effect of surface oxidation was studied and it is demonstrated that oxidation causes substantial increase in the resistance of the nanowire.

  15. Tests of in situ formation scenarios for compact multiplanet systems

    Energy Technology Data Exchange (ETDEWEB)

    Schlaufman, Kevin C., E-mail: kschlauf@mit.edu [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2014-08-01

    Kepler has identified over 600 multiplanet systems, many of which have several planets with orbital distances smaller than that of Mercury. Because these systems may be difficult to explain in the paradigm of core accretion and disk migration, it has been suggested that they formed in situ within protoplanetary disks with high solid surface densities. The strong connection between giant planet occurrence and stellar metallicity is thought to be linked to enhanced solid surface densities in disks around metal-rich stars, so the presence of a giant planet can be a sign of planet formation in a high solid surface density disk. I formulate quantitative predictions for the frequency of long-period giant planets in these in situ models by translating the proposed increase in disk mass into an equivalent metallicity enhancement. I rederive the scaling of giant planet occurrence with metallicity as P{sub gp}=0.05{sub ?0.02}{sup +0.02}×10{sup (2.1±0.4)[M/H]}=0.08{sub ?0.03}{sup +0.02}×10{sup (2.3±0.4)[Fe/H]} and show that there is significant tension between the frequency of giant planets suggested by the minimum mass extrasolar nebula scenario and the observational upper limits. Consequently, high-mass disks alone cannot explain the observed properties of the close-in Kepler multiplanet systems and therefore migration is still important. More speculatively, I combine the metallicity scaling of giant planet occurrence with small planet occurrence rates to estimate the number of solar system analogs in the Galaxy. I find that in the Milky Way there are perhaps 4 × 10{sup 6} true solar system analogs with an FGK star hosting both a terrestrial planet in the habitable zone and a long-period giant planet companion.

  16. Challenges in subsurface in situ remediation of chlorinated solvents

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; FjordbØge, Annika Sidelmann

    2014-01-01

    Chlorinated solvent source zones in the subsurface pose a continuous threat to groundwater quality at many sites worldwide. In situ remediation of these sites is particularly challenging in heterogeneous fractured media and where the solvents are present as DNAPL. In situ remediation by chemical as well as biological degradation of chlorinated solvents is a contact sport and requires direct contact between the contaminant and the reactants and/or degrading microorganisms. In fractured geologic media, where contaminants have spread to the low permeability matrix by diffusion, the contact between contaminant and reactant is limited by slow back diffusion of contaminant and in-diffusion of reactant if the only access for the reactant is via the high permeability fractures/conduits. Where DNAPL is present the mass distribution is very heterogeneous and the reactive degradation is often limited by dissolution of the DNAPL. Most recent research has been aimed at overcoming these challenges by enhanced and targeted reactant delivery methods. These include a wide range of very diverse technologies such as: enhanced injection methods, including fracturing; electrokinetic enhancement of delivery; ZVI-clay mixing for contact; hydrophobic and/or mobile nano-reactants targeting DNAPL. The complexity of the technologies varies greatly and the current level of implementation ranges from multiple full scale applications to bench scale testing. However, the basic degradation reaction involved is usually well established. Enhanced injection with fracturing increases the access to contaminants in clay/clayey media matrixes by shortening the diffusive distance and with ZVI-clay technology by physically mixing the reactant with the contaminated clay/clayey media. The efficiency of the injection technologies has been very variable and rather unpredictable in heterogeneous geologic media, hence, further developments are needed. The novel techniques involving electrokinetics induce migration of primarily ionic species/reactants independent of hydraulic permeability differences, hence transporting the reactant into the contaminated matrix and may be applicable for limestone/bedrock as well as clayey media. Only laboratory studies of electrokinetic enhancement have yet been published, and there is a need for thorough pilot scale studies and supporting laboratory studies. Injectable nano-particles with an affinity for DNAPL surfaces (or phases) may overcome dissolution limitations and provide direct contact with contaminant, limiting reactions with other reactive sites in the subsurface. Challenges lie in obtaining stability and mobility in water, affinity for DNAPL and at the same time maintain reactivity with contaminants. Upscaling to production for pilot studies without loss of efficiency is not trivial. In conclusion there continues to be a need for research and development and in particular for well documented pilot/full scale field studies.

  17. Polypropylene/graphite nanocomposites by in situ polymerization; Nanocompositos polipropileno/grafite via polimerizacao in situ

    Energy Technology Data Exchange (ETDEWEB)

    Milani, Marceo A.; Galland, Giselda B., E-mail: griselda@iq.ufrgs.br [Instituto de Quimica, UFRGS, Porto Alegre, RS (Brazil); Quijada, Raul [Universidade de Chile, Santiago (Chile). Centro de Ciencias de los Materiales; Basso, Nara R.S. [Fac. de Quimica, PUCRS, Porto Alegre, RS (Brazil)

    2011-07-01

    This work presents the synthesis of nanocomposites of polypropylene/graphite by in situ polymerization using metallocene catalyst and graphene nanosheets. Initially was analyzed which of the metallocene catalysts rac-Et(Ind){sub 2}ZrCl{sub 2} or rac-Me{sub 2}Si(Ind){sub 2}ZrCl{sub 2} produces polypropylene with mechanical properties more relevant. Then it were performed the in situ polymerization reactions to obtain the nanocomposites. The polymeric materials were characterized by XRD, DSC, GPC and DMTA. (author)

  18. In situ forming chitosan hydrogels prepared via ionic/covalent co-cross-linking.

    Science.gov (United States)

    Moura, M José; Faneca, H; Lima, M Pedroso; Gil, M Helena; Figueiredo, M Margarida

    2011-09-12

    In situ forming chitosan hydrogels have been prepared via coupled ionic and covalent cross-linking. Thus, different amounts of genipin (0.05, 0.10, 0.15, and 0.20% (w/w)), used as a chemical cross-linker, were added to a solution of chitosan that was previously neutralized with a glycerol-phosphate complex (ionic cross-linker). In this way, it was possible to overcome the pH barrier of the chitosan solution, to preserve its thermosensitive character, and to enhance the extent of cross-linking in the matrix simultaneously. To investigate the contributions of the ionic cross-linking and the chemical cross-linking, separately, we prepared the hydrogels without the addition of either genipin or the glycerol-phosphate complex. The addition of genipin to the neutralized solution disturbs the ionic cross-linking process and the chemical cross-linking becomes the dominant process. Moreover, the genipin concentration was used to modulate the network structure and performance. The more promising formulations were fully characterized, in a hydrated state, with respect to any equilibrium swelling, the development of internal structure, the occurrence of in vitro degradability and cytotoxicity, and the creation of in vivo injectability. Each of the hydrogel systems exhibited a notably high equilibrium water content, arising from the fact that their internal structure (examined by conventional SEM, and environmental SEM) was highly porous with interconnecting pores. The porosity and the pore size distribution were quantified by mercury intrusion porosimetry. Although all gels became degraded in the presence of lysozyme, their degradation rate greatly depended on the genipin load. Through in vitro viability tests, the hydrogel-based formulations were shown to be nontoxic. The in vivo injection of a co-cross-linking formulation revealed that the gel was rapidly formed and localized at the injection site, remaining in position for at least 1 week. PMID:21774479

  19. In-situ thermal testing program strategy

    International Nuclear Information System (INIS)

    In the past year the Yucca Mountain Site Characterization Project has implemented a new Program Approach to the licensing process. The Program Approach suggests a step-wise approach to licensing in which the early phases will require less site information than previously planned and necessitate a lesser degree of confidence in the longer-term performance of the repository. Under the Program Approach, the thermal test program is divided into two principal phases: (1) short-term in situ tests (in the 1996 to 2000 time period) and laboratory thermal tests to obtain preclosure information, parameters, and data along with bounding information for postclosure performance; and (2) longer-term in situ tests to obtain additional data regarding postclosure performance. This effort necessitates a rethinking of the testing program because the amount of information needed for the initial licensing phase is less than previously planned. This document proposes a revised and consolidated in situ thermal test program (including supporting laboratory tests) that is structured to meet the needs of the Program Approach. A customer-supplier model is used to define the Project data needs. These data needs, along with other requirements, were then used to define a set of conceptual experiments that will provide the required data within the constraints of the Program Approach schedule. The conceptual thermal tests presented in this document represent a consolidation and update of previously defined tests that should result in a more efficient use of Project resources. This document focuses on defining the requirements and tests needed to satisfy the goal of a successful license application in 2001, should the site be found suitable

  20. Ekstrauterin graviditet med gestagenspiral in situ

    DEFF Research Database (Denmark)

    Mikkelsen, Mette Schou; Bor, Isil Pinar; Højgaard, Astrid Ditte

    2010-01-01

    The levonorgestrel-releasing intrauterine device (IUD) (Mirena) is a frequently used and effective method of contraception, with a Pearl index of 0.1. The ectopic pregnancy rate is 0.02 per 100 woman-years. Special attention is needed in situations where pregnancy is detected with a levonorgestrel-releasing IUD in situ, because almost two thirds of these pregnancies are ectopic. We describe one of these rare cases of ectopic pregnancy in a woman aged 37 years, who was admitted to hospital with a...

  1. In situ Laue diffraction of metallic micropillars

    Energy Technology Data Exchange (ETDEWEB)

    Maass, R.; Van Petegem, S.; Borca, C.N. [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Van Swygenhoven, H., E-mail: helena.vs@psi.ch [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)

    2009-10-25

    Laue micro-diffraction performed on metallic micropillars prior to deformation revealed the presence of strain gradients and planar defects in samples made by focused ion beam (FIB) milling. In situ Laue micro-diffraction shows that such pre-existing gradients can play a role in the determination of the first activated slip system, and thus leading to un-expected geometrical strengthening. Lattice rotations resulting in the formation of substructures are observed at stresses well below the strength of the pillars usually defined as the stress at 5% strain.

  2. Ekstrauterin graviditet med gestagenspiral in situ

    DEFF Research Database (Denmark)

    Mikkelsen, Mette Schou; Bor, Isil Pinar

    2010-01-01

    The levonorgestrel-releasing intrauterine device (IUD) (Mirena) is a frequently used and effective method of contraception, with a Pearl index of 0.1. The ectopic pregnancy rate is 0.02 per 100 woman-years. Special attention is needed in situations where pregnancy is detected with a levonorgestrel-releasing IUD in situ, because almost two thirds of these pregnancies are ectopic. We describe one of these rare cases of ectopic pregnancy in a woman aged 37 years, who was admitted to hospital with abdominal pain and vaginal bleeding.

  3. In-situ nanoindentation in the SEM

    Directory of Open Access Journals (Sweden)

    Julia D. Nowak

    2010-01-01

    Full Text Available Over the past few decades scanning electron microscopes (SEMs have become commonplace instruments in both academic and industrial settings. With their superior spatial resolution, SEMs have replaced visible-light microscopes in many applications, particularly as the surge in interest in nanotechnology dictates smaller and smaller structures. The limits of these microscopes are now being pushed even further with the development of new in-situ testing methods. Combining SEM imaging with complementary characterization techniques can help to paint a more complete picture of materials behavior. Here we report on progress in the development of a compact, vacuum-compatible instrument capable of quantitative nanomechanical testing in the SEM1.

  4. New horizons of genomic in situ hybridization.

    Czech Academy of Sciences Publication Activity Database

    Marková, Michaela; Vyskot, Boris

    2009-01-01

    Ro?. 126, ?. 4 (2009), s. 368-375. ISSN 1424-8581 R&D Projects: GA ?R(CZ) GD204/09/H002; GA ?R(CZ) GA522/09/0083; GA ?R(CZ) GA521/08/0932; GA MŠk(CZ) LC06004 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : evolution * genomic in situ hybridization * phylogenetics Subject RIV: BO - Biophysics Impact factor: 1.729, year: 2009

  5. In situ SU-8 silver nanocomposites

    DEFF Research Database (Denmark)

    Fischer, SØren Vang; Uthuppu, Basil

    2015-01-01

    Nanocomposite materials containing metal nanoparticles are of considerable interest in photonics and optoelectronics applications. However, device fabrication of such materials always encounters the challenge of incorporation of preformed nanoparticles into photoresist materials. As a solution to this problem, an easy new method of fabricating silver nanocomposites by an in situ reduction of precursors within the epoxy-based photoresist SU-8 has been developed. AgNO3 dissolved in acetonitrile and mixed with the epoxy-based photoresist SU-8 forms silver nanoparticles primarily during the pre- and post-exposure soft bake steps at 95 degrees C. A further high-temperature treatment at 300 degrees C resulted in the formation of densely homogeneously distributed silver nanoparticles in the photoresist matrix. No particle growth or agglomeration of nanoparticles is observed at this point. The reported new in situ silver nanocomposite materials can be spin coated as homogeneous thin films and structured by using UV lithography. A resolution of 5 mu m is achieved in the lithographic process. The UV exposure time is found to be independent of the nanoparticle concentration. The fabricated silver nanocomposites exhibit high plasmonic responses suitable for the development of new optoelectronic and optical sensing devices.

  6. In situ combustion field experiences in Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Villalba, M.; Estrada, M.; Bolivar, J. [INTEVEP, Caracas (Venezuela)

    1995-02-01

    A literature review of four in situ combustion projects: in Miga, Tia Juana, Melones and Morichal fields in Venezuela was made, and a summary of these projects is presented. Reservoir description and project performance data were analyzed. The behavior of the four in situ combustion field tests can be summarized as follows: The problems most often encountered were corrosion and high temperature producing wells. The direction in which the burning front moved was guided essentially by reservoir characteristics. The produced oil was upgraded by about 4{degrees} API, and viscosity was substantially reduced. For Mirochal and Miga fields, the analyses of available information from the combustion projects indicated that the process has been successful in the affected region. Conclusions from this review indicate that the two most frequent problems encountered were operational problems in producing wells and the direction of the burning front. The heterogeneous nature of the sands probably resulted in the burning front moving in a preferential direction, hence reducing areal sweep efficiency.

  7. Inherently safe in situ uranium recovery.

    Energy Technology Data Exchange (ETDEWEB)

    Krumhansl, James Lee; Beauheim, Richard Louis; Brady, Patrick Vane; Arnold, Bill Walter; Kanney, Joseph F.; McKenna, Sean Andrew

    2009-05-01

    Expansion of uranium mining in the United States is a concern to some environmental groups and sovereign Native American Nations. An approach which may alleviate some problems is to develop inherently safe in situ uranium recovery ('ISR') technologies. Current ISR technology relies on chemical extraction of trace levels of uranium from aquifers that, once mined, can still contain dissolved uranium and other trace metals that are a health concern. Existing ISR operations are few in number; however, high uranium prices are driving the industry to consider expanding operations nation-wide. Environmental concerns and enforcement of the new 30 ppb uranium drinking water standard may make opening new mining operations more difficult and costly. Here we propose a technological fix: the development of inherently safe in situ recovery (ISISR) methods. The four central features of an ISISR approach are: (1) New 'green' leachants that break down predictably in the subsurface, leaving uranium, and associated trace metals, in an immobile form; (2) Post-leachant uranium/metals-immobilizing washes that provide a backup decontamination process; (3) An optimized well-field design that increases uranium recovery efficiency and minimizes excursions of contaminated water; and (4) A combined hydrologic/geochemical protocol for designing low-cost post-extraction long-term monitoring. ISISR would bring larger amounts of uranium to the surface, leave fewer toxic metals in the aquifer, and cost less to monitor safely - thus providing a 'win-win-win' solution to all stakeholders.

  8. Speckle interferometry in situ: a feasibility study

    Science.gov (United States)

    Facchini, Massimo

    1998-06-01

    Speckle interferometry has been successfully used in many cases where a non-contact analysis of a surface's deformation state was required. This technique has been mostly applied in favorable environment, where the absence of vibrations and a reduced ambient illumination could be assured, and for the observation of areas being not in excess of some dm2. When inspecting larger surfaces, all the problems related to the spatial resolution, to the limited sensitivity of the acquisition system, to the amount of illumination and to the extension of the observed area, should be taken into account. If the observed surface belongs to a structure directly positioned in-situ, problems of vibration, air turbulence, or ambient light saturation, become very restrictive for the application of the method. After a brief introduction about the theoretical principles of speckle interferometry, some main problems related to the inspection on quite large surfaces in-situ discussed. The problem is treated with the help of some simulations, possible solutions are proposed and some applications are presented. This work is the result of a joint collaboration between may institutes and research centers in the framework of a European project named VISILAS. Special fields of application foreseen for this project are civil engineering, aircraft industry, ship building and power plants for energy production.

  9. GAS TURBINE REHEAT USING IN SITU COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    D.M. Bachovchin; T.E. Lippert; R.A. Newby P.G.A. Cizmas

    2004-05-17

    In situ reheat is an alternative to traditional gas turbine reheat design in which fuel is fed through airfoils rather than in a bulky discrete combustor separating HP and LP turbines. The goals are to achieve increased power output and/or efficiency without higher emissions. In this program the scientific basis for achieving burnout with low emissions has been explored. In Task 1, Blade Path Aerodynamics, design options were evaluated using CFD in terms of burnout, increase of power output, and possible hot streaking. It was concluded that Vane 1 injection in a conventional 4-stage turbine was preferred. Vane 2 injection after vane 1 injection was possible, but of marginal benefit. In Task 2, Combustion and Emissions, detailed chemical kinetics modeling, validated by Task 3, Sub-Scale Testing, experiments, resulted in the same conclusions, with the added conclusion that some increase in emissions was expected. In Task 4, Conceptual Design and Development Plan, Siemens Westinghouse power cycle analysis software was used to evaluate alternative in situ reheat design options. Only single stage reheat, via vane 1, was found to have merit, consistent with prior Tasks. Unifying the results of all the tasks, a conceptual design for single stage reheat utilizing 24 holes, 1.8 mm diameter, at the trailing edge of vane 1 is presented. A development plan is presented.

  10. In situ PEM fuel cell water measurements

    Energy Technology Data Exchange (ETDEWEB)

    Borup, Rodney L [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Davey, John R [Los Alamos National Laboratory; Spendelow, Jacob S [Los Alamos National Laboratory; Hussey, Daniel S [NIST; Jacobson, David L [NIST; Arif, Muhammad [NIST

    2009-01-01

    Efficient PEM (Polymer Electrolyte Membrane) fuel cell performance requires effective water management. To achieve a deeper understanding of water transport and performance issues associated with water management, we have conducted in situ water examinations to help understand the effects of components and operations. High Frequency Resistance (HFR), AC Impedance and Neutron imaging were used to measure water content in operating fuel cells, with various conditions, including current density, relative humidity, inlet flows, flow orientation and variable Gas Diffusion Layer (GDL) properties. High resolution neutron radiography was used to image fuel cells during a variety of conditions. The effect of specific operating conditions, including flow direction (co-flow or counter-flow) was examined. Counter-flow operation was found to result in higher water content than co-flow operation, which correlates to lower membrane resistivity. A variety of cells were used to quantify the membrane water in situ during exposure to saturated gases, during fuel cell operation, and during hydrogen pump operation. The quantitative results show lower membrane water content than previous results suggested.

  11. In situ bioremediation under high saline conditions

    International Nuclear Information System (INIS)

    An in situ bioremediation treatability study is in progress at the Salton Sea Test Base (SSTB) under the NAVY CLEAN 2 contract. The site is located in the vicinity of the Salon Sea with expected groundwater saline levels of up to 50,000 ppm. The site is contaminated with diesel, gasoline and fuel oils. The treatability study is assessing the use of indigenous heterotrophic bacteria to remediate petroleum hydrocarbons. Low levels of significant macro nutrients indicate that nutrient addition of metabolic nitrogen and Orthophosphate are necessary to promote the process, requiring unique nutrient addition schemes. Groundwater major ion chemistry indicates that precipitation of calcium phosphorus compounds may be stimulated by air-sparging operations and nutrient addition, which has mandated the remedial system to include pneumatic fracturing as an option. This presentation is tailored at an introductory level to in situ bioremediation technologies, with some emphasize on innovations in sparge air delivery, dissolved oxygen uptake rates, nutrient delivery, and pneumatic fracturing that should keep the expert's interest

  12. Biophotonic in situ sensor for plant leaves

    International Nuclear Information System (INIS)

    Knowledge of the water concentration of plants can be helpful in several environmental and agricultural domains. There are many methods for the determination of water content in plant leaves; however, most of them give a relative moisture level or an analytical measure after a previous calibration procedure. Even for other biochemical compounds such as dry matter or chlorophyll, the measurement techniques could be destructive. For this reason, a nondestructive method has been developed to measure the biochemical compounds of a plant leaf, using an infrared spectroscopy technique. One important advantage is the simplicity of the device (RAdiometre portatif de Mesure In Situ, RAMIS) and its capability to perform measurements in situ. The prototype is a leaf-clip configuration and is made of LEDs at five wavelengths (656, 721, 843, 937, and 1550 nm), and a silicon/germanium photosensor. To compute the water content of vegetative leaves, the radiative transfer model PROSPECT was implemented. This model can accurately predict spectral transmittances in the 400 nm to 2500 nm spectral region as a function of the principal leaf biochemical contents: water, dry matter, and chlorophyll. Using the transmittance measured by RAMIS into an inversion procedure of PROSPECT: A Model of Leaf Optical Properties Spectra, we are able to compute the values of water contents that show an agreement with the water contents measured directly using dry weight procedures. This method is presented as a possibility to estimate other leaf biochemical compounds using appropriate wavelengths.

  13. Dosimetry of in situ activated dysprosium microspheres

    International Nuclear Information System (INIS)

    This paper presents the results of a study aimed at investigating the dosimetry of stable dysprosium microspheres activated, in situ, by a linac generated photon beam. In phantom measurements of the neutron flux within an 18 MV photon beam were performed using CR-39 detectors and gold activation. The results were used in conjunction with a Monte Carlo computer simulation to investigate the dose distribution resulting from the activation of dysprosium (Dy) microspheres using an 18 MV photon beam. Different depths, lesion volumes and volume concentrations of microspheres are investigated. The linac lower collimator jaws are assumed completely closed to shield the tumour volume from the photon dose. Using a single AP field with 0 x 0 cm2 field size (closed jaws), a photon dose rate of 600 MU min-1 and 80 cm SSD for 10 min, an average dose exceeding 1 Gy can be delivered to spherical lesions of 0.5 cm and higher diameter. The variation of the average dose with the size of the lesion reaches saturation for tumour volumes exceeding 1 cm in diameter. This report shows that the photon beam of a high-energy linac can be used to activate Dy microspheres in situ and, as a result, deliver a significant dose of beta radiation. Non-radioactive Dy microspheres do not have the toxicity and imaging problems associated with commercially available yttrium-90 based products

  14. Molecular cytogenetics using fluorescence in situ hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.W.; Kuo, Wen-Lin; Lucas, J.; Pinkel, D.; Weier, H-U.; Yu, Loh-Chung.

    1990-12-07

    Fluorescence in situ hybridization (FISH) with chromosome-specific probes enables several new areas of cytogenetic investigation by allowing visual determination of the presence and normality of specific genetic sequences in single metaphase or interphase cells. in this approach, termed molecular cytogenetics, the genetic loci to be analyzed are made microscopically visible in single cells using in situ hybridization with nucleic acid probes specific to these loci. To accomplish this, the DNA in the target cells is made single stranded by thermal denaturation and incubated with single-stranded, chemically modified probe under conditions where the probe will anneal only with DNA sequences to which it has high DNA sequence homology. The bound probe is then made visible by treatment with a fluorescent reagent such as fluorescein that binds to the chemical modification carried by the probe. The DNA to which the probe does not bind is made visible by staining with a dye such as propidium iodide that fluoresces at a wavelength different from that of the reagent used for probe visualization. We show in this report that probes are now available that make this technique useful for biological dosimetry, prenatal diagnosis and cancer biology. 31 refs., 3 figs.

  15. Studies on the intercalation of naproxen into layered double hydroxide and its thermal decomposition by in situ FT-IR and in situ HT-XRD

    International Nuclear Information System (INIS)

    Layered double hydroxides, novel anionic clay, meet the first requirement as inorganic matrices for encapsulating functional drugs or biomolecules with negative charge in aqueous media. In this study, naproxen has been intercalated into Mg-Al layered double hydroxide by the methods of ion exchange. The structure and composition of the intercalated material have been studied by X-ray diffraction (XRD), UV-vis spectroscopy and inductively coupled plasma emission spectroscopy. A schematic model has been proposed. Furthermore, in situ Fourier transform infrared spectroscopy, in situ high-temperature XRD, and thermogravimetry (TG) have been used to characterize the thermal decomposition of the hybrid material. It has been found that the thermal stability of the intercalated naproxen is significantly enhanced compared with the pure form before intercalation, which suggests that this drug-inorganic layered material may have prospective application as the basis of a novel drug delivery system

  16. Mitigating Extreme Environments for In-Situ Jupiter and Venus Missions

    Science.gov (United States)

    Balint, Tibor S.; Kolawa, Elizabeth A.; Cutts, James A.

    2006-01-01

    In response to the recommendations by the National Research Council (NRC), NASA's Solar System Exploration (SSE) Roadmap identified the in situ exploration of Venus and Jupiter as high priority science objectives. For Jupiter, deep entry probes are recommended, which would descend to approx.250 km - measured from the 1 bar pressure depth. At this level the pressure would correspond to approx.100 bar and the temperature would reach approx.500(deg)C. Similarly, at the surface of Venus the temperature and pressure conditions are approx.460(deg)C and approx.90 bar. Lifetime of the Jupiter probes during descent can be measured in hours, while in{situ operations at and near the surface of Venus are envisioned over weeks or months. In this paper we discuss technologies, which share commonalities in mitigating these extreme conditions over proposed mission lifetimes, specially focusing on pressure and temperature environments.

  17. Actinobacillus pleuropneumoniae osteomyelitis in pigs demonstrated by fluorescent in situ hybridization

    DEFF Research Database (Denmark)

    Jensen, Tim Kåre; Boye, Mette

    1999-01-01

    Necrotizing osteomyelitis and fibrinopurulent arthritis with isolation of Actinobacillus pleuropneumoniae serotype 2 is reported in two pigs from a herd with lameness and mild coughing problems among 8 to 12-week-old pigs. Application of fluorescent in situ hybridization targeting 16S ribosomal RNA of A. pleuropneumoniae in formalin-fixed tissue was performed to verify the association of A. pleuropneumoniae with the bone and joint lesions. By in situ hybridization A. pleuropneumoniae was demonstrated as multiple microcolonies or single cells dispersed in focal fibrinonecrotizing pleuropneumonia, in joints with arthritis, and in bone necroses including lysis of growth plate and suppurative inflammation in the adjacent trabecular metaphysis, thus demonstrating that well-known infections manifest new, unusual lesions.

  18. 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

  19. Chitosan/glucose 1-phosphate as new stable in situ forming depot system for controlled drug delivery.

    Science.gov (United States)

    Supper, Stephanie; Anton, Nicolas; Boisclair, Julie; Seidel, Nina; Riemenschnitter, Marc; Curdy, Catherine; Vandamme, Thierry

    2014-10-01

    Chitosan (CS)-based thermosensitive solutions that turn into semi-solid hydrogels upon injection at body temperature have increasingly drawn attention over the last decades as an attractive new type of in situ forming depot (ISFD) drug delivery system. Despite the great potential of the standard CS/?-glycerophosphate (?-GP) thermogelling solutions, their lack of stability over time at room temperature as well as at refrigerated conditions renders them unsuitable as ready-to-use drug product. In the present study, we investigated Glucose-1-Phosphate (G1-P) as an alternative gelling agent for improving the stability of CS-based ISFD solutions. The in vitro release performance of CS/G1-P formulations was assessed using several model compounds. Furthermore, the local tolerance of subcutaneously implanted CS/G1-P hydrogels was investigated by histological examination over three weeks. The thermogelling potential of CS/G1-P solutions, determined by rheology, is dependent on the polymer molecular weight (Mw) and concentration as well as on the G1-P concentration. Differential scanning calorimetry (DSC) measurements confirmed that sol/gel transition takes place at around body temperature and is not fully thermo-reversible. The long term storage stability was evaluated through the appearance, pH, viscosity and gelation time at 37°C of the solution. The results emphasized an enhanced stability of the CS/G1-P system compared to the standard CS/?-GP. CS solution with 0.40 mmol/g G1-P is stable for at least 9 months at 2-8°C, versus less than 1 month when using ?-GP as gelling agent. Furthermore, the solution is easy to inject, as evidenced from injectability evaluation using 23-30 G needles. In vitro release experiments showed a sustained release over days to weeks for hydrophilic model compounds, demonstrating thereby that CS/G1-P may be suitable for the prolonged delivery of drugs. The inflammatory reaction observed in the tissue surrounding the hydrogel in rats was a typical foreign body reaction, similar to the one observed for CS/?-GP hydrogels. These features confirm the potential of CS/G1-P solutions as an injectable ready-to-use in situ forming hydrogel. PMID:24859306

  20. Osteogenic potential of in situ TiO2 nanowire surfaces formed by thermal oxidation of titanium alloy substrate

    Science.gov (United States)

    Tan, A. W.; Ismail, R.; Chua, K. H.; Ahmad, R.; Akbar, S. A.; Pingguan-Murphy, B.

    2014-11-01

    Titanium dioxide (TiO2) nanowire surface structures were fabricated in situ by a thermal oxidation process, and their ability to enhance the osteogenic potential of primary osteoblasts was investigated. Human osteoblasts were isolated from nasal bone and cultured on a TiO2 nanowires coated substrate to assess its in vitro cellular interaction. Bare featureless Ti-6Al-4V substrate was used as a control surface. Initial cell adhesion, cell proliferation, cell differentiation, cell mineralization, and osteogenic related gene expression were examined on the TiO2 nanowire surfaces as compared to the control surfaces after 2 weeks of culturing. Cell adhesion and cell proliferation were assayed by field emission scanning electron microscope (FESEM) and Alamar Blue reduction assay, respectively. The nanowire surfaces promoted better cell adhesion and spreading than the control surface, as well as leading to higher cell proliferation. Our results showed that osteoblasts grown onto the TiO2 nanowire surfaces displayed significantly higher production levels of alkaline phosphatase (ALP), extracellular (ECM) mineralization and genes expression of runt-related transcription factor (Runx2), bone sialoprotein (BSP), ostoepontin (OPN) and osteocalcin (OCN) compared to the control surfaces. This suggests the potential use of such surface modification on Ti-6Al-4V substrates as a promising means to improve the osteointegration of titanium based implants.

  1. In situ lubricant degradation in Antarctic marine sediments. 1. Short-term changes.

    Science.gov (United States)

    Thompson, Belinda A W; Davies, Noel W; Goldsworthy, Paul M; Riddle, Martin J; Snape, Ian; Stark, Jonathan S

    2006-02-01

    A large-scale, in situ experiment was set up near the Bailey Peninsula area (Casey Station, East Antarctica) to monitor the natural attenuation of synthetic lubricants in marine sediments over five years. Here, we report the short-term changes after 5 and 56 weeks. The lubricants tested were an unused and used Mobil lubricant (0W/40; Exxon Mobil, Irving, TX, USA) and a biodegradable alternative (0W/20; Fuchs Lubricants, Harvey, IL, USA). Clean sediment was collected, contaminated with the lubricants, and deployed by divers onto the seabed in a randomized block design. The sampled sediments were analyzed by gas chromatography-flame-ionization detector and gas chromatography-mass spectrometry with selective ion monitoring. The base fluid of all lubricant treatments did not decrease significantly after 56 weeks in situ. Alkanoate esters of 1,1,1-tris(hydroxymethyl)propane in the biodegradable and unused lubricants were degraded extensively in situ; however, these esters constituted only a minor proportion of the lubricant volume. The additives, alkylated naphthalenes and substituted diphenylamines, were fairly resistant to degradation, which is of environmental concern because of their toxicity. The biodegradable lubricant did not break down to recognized biodegradable thresholds and, as such, should not be classified as biodegradable under Antarctic marine conditions. A separate experiment was conducted to determine the influence of sediment preparation and deployment on compound ratios within the lubricants, and we found that preparation and deployment of the contaminated sediments had only a minor effect on compound recovery. Further monitoring of this in situ experiment will provide much needed information about the long-term natural attenuation of lubricants. PMID:16519295

  2. The LISA1 experiment: In-situ tritium release investigations

    International Nuclear Information System (INIS)

    The LISA1 experiment is a test of in-situ tritium release. Conducted in the SILOE reactor at CEN Grenoble, the experiment uses the same facilities as the LILA1. The experiment has six capsules, four with Li2SiO3, one with Li4SiO4 and one with LiAlO2. Each capsule is separately purged. The tritium activity is determined by ionization chambers and scintillation counting. An important difference as compared to LILA1 is the use of zinc beds to reduce tritiated water and thereby prevent sorption of T2O on the lines. Irradiation began on October 25, 1985 and was continued for three 3-weeks-cycles. The testing included systematic variation of four parameters: temperature (450 to 7300C), neutron flux (0.8 to 2.7x1017 m-2 s-1), sweep gas flow rate (1.8 to 7.0 l/h), and sweep gas composition (He, He+0.1% H2, He+0.2% O2). Preliminary results are given. (orig.)

  3. 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

  4. Thermally Triggered Mucoadhesive In Situ Gel of Loratadine: ?-Cyclodextrin Complex for Nasal Delivery

    OpenAIRE

    Singh, Reena M. P.; Kumar, Anil; Pathak, Kamla

    2013-01-01

    The aim of the present study was to increase the solubility of an anti-allergic drug loratadine by making its inclusion complex with ?-cyclodextrin and to develop it’s thermally triggered mucoadhesive in situ nasal gel so as to overcome first-pass effect and consequently enhance its bioavailability. A total of eight formulations were prepared by cold method and optimized by 23 full factorial design. Independent variables (concentration of poloxamer 407, concentration of carbopol 934 P, and pu...

  5. Dynamics of silver nanoparticle release from wound dressings revealed via in situ nanoscale imaging

    OpenAIRE

    Holbrook, R David; Rykaczewski, Konrad; Staymates, Matthew E.

    2014-01-01

    The use of silver nanoparticles (AgNPs) in textiles for enhanced anti-microbial properties has led to concern about their release and impact on both human and environmental health. Here a novel method for in situ visualization of AgNP release from silver-impregnated wound dressings is introduced. By combining an environmental scanning electron microscope, a gaseous analytical detector and a peltier cooling stage, this technique provides near-instantaneous nanoscale characterization of interac...

  6. In situ-grown hexagonal silicon nanocrystals in silicon carbide-based films

    OpenAIRE

    Kim, Tae-Youb; Huh, Chul; Park, Nae-Man; Choi, Cheol-Jong; Suemitsu, Maki

    2012-01-01

    Silicon nanocrystals (Si-NCs) were grown in situ in carbide-based film using a plasma-enhanced chemical vapor deposition method. High-resolution transmission electron microscopy indicates that these nanocrystallites were embedded in an amorphous silicon carbide-based matrix. Electron diffraction pattern analyses revealed that the crystallites have a hexagonal-wurtzite silicon phase structure. The peak position of the photoluminescence can be controlled within a wavelength of 500 to 650 nm by ...

  7. In situ ductile toughening of Nb2Al by combustion synthesis

    International Nuclear Information System (INIS)

    This paper ductile toughening of niobium aluminide (Nb2Al) that has been accomplished in situ while combustion synthesizing the compound from a mixture of Nb, Al and 3 wt% B powders. An enhancement of the fracture toughness of the resulting Nb2Al has been shown to be primarily caused by the interaction of propagating cracks and cores of ductile Nb phases inside the partly combusted Nb powders

  8. In Situ-Synthesized Virulence and Marker Gene Biochip for Detection of Bacterial Pathogens in Water? †

    OpenAIRE

    Miller, Sarah M.; Tourlousse, Dieter M; Stedtfeld, Robert D; Baushke, Samuel W.; Herzog, Amanda B.; Wick, Lukas M.; Rouillard, Jean Marie; Gulari, Erdogan; Tiedje, James M.; Hashsham, Syed A

    2008-01-01

    Pathogen detection tools with high reliability are needed for various applications, including food and water safety and clinical diagnostics. In this study, we designed and validated an in situ-synthesized biochip for detection of 12 microbial pathogens, including a suite of pathogens relevant to water safety. To enhance the reliability of presence/absence calls, probes were designed for multiple virulence and marker genes (VMGs) of each pathogen, and each VMG was targeted by an average of 17...

  9. Radiological aspects of in situ uranium recovery

    International Nuclear Information System (INIS)

    In the last few years, there has been a significant increase in the demand for Uranium as historical inventories have been consumed and new reactor orders are being placed. Numerous mineralized properties around the world are being evaluated for Uranium recovery and new mining / milling projects are being evaluated and developed. Ore bodies which are considered uneconomical to mine by conventional methods such as tunneling or open pits, can be candidates for non-conventional recovery techniques, involving considerably less capital expenditure. Technologies such as Uranium in situ leaching in situ recovery (ISL / ISR), have enabled commercial scale mining and milling of relatively small ore pockets of lower grade, and may make a significant contribution to overall world wide uranium supplies over the next ten years. Commercial size solution mining production facilities have operated in the US since 1975. Solution mining involves the pumping of groundwater, fortified with oxidizing and complexing agents into an ore body, solubilizing the uranium in situ, and then pumping the solutions to the surface where they are fed to a processing plant. Processing involves ion exchange and may also include precipitation, drying or calcining and packaging operations depending on facility specifics. This paper presents an overview of the ISR process and the health physics monitoring programs developed at a number of commercial scale ISL / ISR Uranium recovery and production facilities as a result of the radiological character of these processes. Although many radiological aspects of the process are similar to that of conventional mills, conventional-type tailings as such are not generated. However, liquid and solid byproduct materials may be generated and impounded. The quantity and radiological character of these by products are related to facility specifics. Some special monitoring considerations are presented which are required due to the manner in which Radon gas is evolved in the process and the unique aspects of controlling solution flow patterns underground. An overview of the major aspects of the health physics and radiation protection programs that were developed at these facilities are discussed and contrasted to circumstances of the current generation and state of the art of Uranium ISR technologies and facilities. (authors)

  10. In-situ gelling polymers for biomedical applications

    CERN Document Server

    2015-01-01

    This book presents the research involving in situ gelling polymers and can be used as a guidebook for academics, industrialists and postgraduates interested in this area. This work summaries the academic contributions from the top authorities in the field and explore the fundamental principles of in situ gelling polymeric networks, along with examples of their major applications. This book aims to provide an up-to-date resource of in situ gelling polymer research.

  11. Human papillomavirus (HPV) in vulvar dysplasia and carcinoma in situ

    DEFF Research Database (Denmark)

    Junge, Jette; Poulsen, H; Horn, T; Hørding, U; Lundvall, F

    1995-01-01

    Surgical specimens from 62 patients with vulvar dysplasia and carcinoma in situ were morphologically investigated. Lesions were classified according to WHO (mild, moderate, severe dysplasia and carcinoma in situ) and according to Toki et al. (1991) (warty, basaloid, combined warty/basaloid or basaloid/warty types or mixed (warty, basaloid and simple) forms). Following the WHO classification, moderate dysplasia was shown in 4 cases, severe dysplasia in 47 and carcinoma in situ in 11 cases. Pure w...

  12. Enhanced mobility of the cluster Ru-3(CO)(12) in the solid state formed in situ by the reaction of CO and Ru-3(CO)(6)(mu-CO)(mu(3):eta 2 :eta 3 :eta 5-C12H8) on silica

    OpenAIRE

    Aime, Silvio; Gobetto, Roberto

    2000-01-01

    The reaction of Ru-3(CO)(6)(mu-CO)(mu(3):eta(2):eta(3):eta(5)-C12H8) (physisorbed on SiO2) with CO in the solid state leads to Ru-3(CO)(12) and acenaphthylene in quantitative yields; the Ru-3(CO)(12) generated in situ is highly mobile leading to a reduced chemical shielding anisotropy.

  13. Effect of surface charge on the brain delivery of nanostructured lipid carriers in situ gels via the nasal route.

    Science.gov (United States)

    Gabal, Yasmine M; Kamel, Amany O; Sammour, Omaima A; Elshafeey, Ahmed H

    2014-10-01

    The aim of this study was to investigate the influence of the nanocarrier surface charge on brain delivery of a model hydrophilic drug via the nasal route. Anionic and cationic nanostructured lipid carriers (NLCs) were prepared and optimized for their particle size and zeta potential. The optimum particles were incorporated in poloxamer in situ gels and their in vivo behavior was studied in the plasma and brain after administration to rats. Optimum anionic and cationic NLCs of size NLCs (A7), and destruction of the lining mucosal nasal epithelium in rats treated with the cationic NLCs (C7L). The absolute bioavailability of both drug loaded anionic and cationic NLCs in situ gels was enhanced compared to that of the intranasal solution (IN) of the drug with values of 44% and 77.3%, respectively. Cationic NLCs in situ gel showed a non significant higher Cmax (maximum concentration) in the brain compared to the anionic NLCs in situ gel. Anionic NLCs in situ gel gave highest drug targeting efficiency in the brain (DTE%) with a value of 158.5 which is nearly 1.2 times that of the cationic NLCs in situ gel. PMID:25062866

  14. Numerical study on in-situ leaching uranium with pressure fluctuation

    International Nuclear Information System (INIS)

    Recent researches and innovation of in-situ leaching focus on the chemical process, which can not solve the low recovery in 'dead leaching zone' and 'non-preferential zone' caused by preferential flow and solute transport phenomena in heterogeneous ore deposits. Based on hydrodynamic effects and phenomena in highly heterogeneous porous media, gas injection experiments and laboratory experiment results, an innovative method for in-situ leaching, named as leaching with pressure fluctuation, was put forward to enhance the leaching effect and uranium recovery, especially in those uranium ore deposits with high heterogeneity. Based on the characteristics of gas/liquid mixture and flow-reactive-transport theory, a numerical modeling tool is established. By the numerical simulation, the field-scale traditional leaching method and the new method were studied. The simulation results show that the gas-liquid mixture will expand/shrink greatly in different flow zone during the pressure fluctuation process, and the deformation will enhance the solute transport effect among different flow zones, especially in non-preferential flow zone, and enhance the uranium recovery. The primary results show that in-situ leaching with pressure fluctuation is feasible technically. (authors)

  15. An Efficient Heat Exchanger for In Situ Resource Utilization Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In situ resource utilization (ISRU) is essential for several of NASA's future flagship missions. Currently envisioned ISRU plants include production of oxygen from...

  16. In situ test requirements for repository in salt

    International Nuclear Information System (INIS)

    For the characterization and evaluation of salt as suitable geologic media, a comprehensive investigative program is being implemented in the U.S.A. A key element of the program is in situ testing. In situ tests have been performed in the past at Lyons, Kansas, and are currently under way at Avery Island, Louisiana and at the Asse Mine in the Federal Republic of Germany (FRG). This paper presents the rationale and requirements for in situ testing in salt, status of current testing programs, and planning for in situ tests from an exploratory shaft. 6 refs.; 6 figs.; 2 tabs

  17. SMAPVEX08 In Situ Vegetation Data V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set includes in situ vegetation data collected during the Soil Moisture Active Passive Validation Experiment 2008 (SMAPVEX08) campaign. Sampling was...

  18. Debottlenecking product inhibition in 1,3-propanediol fermentation by In-Situ Product Recovery.

    Science.gov (United States)

    Kaur, Guneet; Srivastava, A K; Chand, Subhash

    2015-12-01

    The present work describes the application of liquid-liquid extraction as an In-Situ product recovery (ISPR) technique to overcome the problem of product inhibition in 1,3-PD fermentation. As a part of initial screening experiments, six solvents were subjected to phase separation and biocompatibility tests to find the best extractant for in-situ removal of 1,3-PD from the bioreactor. These included tributylphosphate, ethyl acetate, butyl acetate, oleyl alcohol, oleic acid and hexanol. Of these, ethyl acetate was found to be the most suitable solvent for 1,3-PD extraction. Use of the selected extractant in continuous integrated fermentation-extraction was established by batch and fed-batch extractive fermentations which demonstrated a significantly improved 1,3-PD production of 35g/L and 74.5g/L, respectively. A steady state 1,3-PD concentration of 58g/L was obtained in continuous extractive system. Continuous cultivation with in-situ cell retention and in-situ 1,3-PD removal demonstrated a 5-fold enhancement in 1,3-PD productivity over non-extractive batch. PMID:26356117

  19. In Situ Fabrication and Repair (ISFR) Technologies; New Challenges for Exploration

    Science.gov (United States)

    Bassler, Julie A.; Bodiford, Melanie P.; Hammond, Monica S.; King, Ron; Mclemore, Carole A.; Hall, Nancy R.; Fiske, Michael R.; Ray, Julie A.

    2006-01-01

    NASA's human exploration initiative poses great opportunity and great risk for manned missions to the Moon and Mars. Engineers and Scientists at the Marshall Space Flight Center (MSFC) are continuing to evaluate current technologies for in situ resource-based exploration fabrication and repair applications. Several technologies to be addressed in this paper have technology readiness levels (TRLs) that are currently mature enough to pursue for exploration purposes. However, while many technologies offer promising applications, these technologies must be pulled along by the demands and applications of this great initiative. The In Situ Fabrication and Repair (ISFR) Element will supply and push state of the art technologies for applications such as habitat structure development, in situ resource utilization for tool and part fabrication, and repair and non-destructive evaluation W E ) of common life support elements. As an overview of the ISFR Element, this paper will address rapid prototyping technologies, their applications, challenges, and near term advancements. This paper will also discuss the anticipated need to utilize in situ resources to produce replacement parts and fabricate repairs to vehicles, habitats, life support and quality of life elements. Overcoming the challenges of ISFR development will provide the Exploration initiative with state of the art technologies that reduce risk, and enhance supportability.

  20. Cryogenic in situ microcompression testing of Sn

    International Nuclear Information System (INIS)

    Characterizing plasticity mechanisms below the ductile-to-brittle transition temperature is traditionally difficult to accomplish in a systematic fashion. Here, we use a new experimental setup to perform in situ cryogenic mechanical testing of pure Sn micropillars at room temperature and at ?142 °C. Subsequent electron microscopy characterization of the micropillars shows a clear difference in the deformation mechanisms at room temperature and at cryogenic temperatures. At room temperature, the Sn micropillars deformed through dislocation plasticity, while at ?142 °C they exhibited both higher strength and deformation twinning. Two different orientations were tested, a symmetric (1 0 0) orientation and a non-symmetric (4 5¯ 1) orientation. The deformation mechanisms were found to be the same for both orientations

  1. In situ studies of fracture in solids

    International Nuclear Information System (INIS)

    Electron microscope studies were made of the propagation of microcracks during in situ tensile deformation of stainless steel, molybdenum and magnesium oxide representing ductile, semi-brittle and brittle solids. As the stress is applied, the cracks are initiated at the edge of holes in the thinned foils. The extent of plastic activity around the cracks is measured in terms of the density and the distribution of dislocations and is sensitive to the ductile/brittle nature of the solid. The slip systems of the dislocations are determined by contrast analysis and stereoscopic observation. In stainless steel and magnesium oxide, the dislocations are relatively straight and they lie nearly perpendicular to the direction of the crack propagation, whereas in molybdenum the dislocations are in the form of irregular tangles which are stretched along the direction of the crack propagation. These observations are discussed in terms of the model of Dugdale concerning the formation of plastic zones under uniaxial loading in plane stress conditions

  2. In situ erosion of cohesive sediment

    International Nuclear Information System (INIS)

    There has been increasing interest in tidal power schemes and the effect of a tidal energy barrage on the environment. A large man-made environmental change, such as a barrage, would be expected to have significant effects on the sediment distribution and stability of an estuary and these effects need to be assessed when considering a tidal barrage project. This report describes the development of apparatus for in-situ measurements of cohesive sediment erosion on inter-tidal mudflats. Development of the prototype field erosion bell and field testing was commissioned on behalf of the Department of Trade and Industry by the Energy Technology Support Unit (ETSU). This later work commenced in August 1991 and was completed in September 1992. (Author)

  3. PREPARATION OF NANOCOMPOSITES BY IN SITU POLIMERIZATION

    Directory of Open Access Journals (Sweden)

    PAULA ZAPATA

    2008-03-01

    Full Text Available Polyethylene nanocomposites were obtained by in situ polymerization using both montmorillonite (natural clay and montmorillonite organically modified with octadecylamine (O-Clo. In this proposed methodology the clays were added directly in the reactor together with the catalytic system (metallocene catalyst and methylaluminoxane and ethylene. The nanocomposites were characterized by gel permeation chromatography (GPC, differential scanning calorimetry (DSC, X-ray diffraction (XRD, and transmission electron microscopy (TEM, and by tensile stress-strain tests. It was found that the catalytic activity increased around 20% when natural clay was used compared with the standard polymer. But when modified clay was used the catalytic activity did not show important changes. On the other hand, XRD and TEM showed that the clays are in a disordered state and well dispersed in the polyethylene matrix. Finally, the nanocomposites showed an increase of about 30% in Young's modulus compared with the standard polymer

  4. PREPARATION OF NANOCOMPOSITES BY IN SITU POLIMERIZATION

    Scientific Electronic Library Online (English)

    PAULA, ZAPATA; RAÚL, QUIJADA; JAIME, RETUER; EDWIN, MONCADA.

    2008-03-01

    Full Text Available Polyethylene nanocomposites were obtained by in situ polymerization using both montmorillonite (natural clay) and montmorillonite organically modified with octadecylamine (O-Clo). In this proposed methodology the clays were added directly in the reactor together with the catalytic system (metallocen [...] e catalyst and methylaluminoxane) and ethylene. The nanocomposites were characterized by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and transmission electron microscopy (TEM), and by tensile stress-strain tests. It was found that the catalytic activity increased around 20% when natural clay was used compared with the standard polymer. But when modified clay was used the catalytic activity did not show important changes. On the other hand, XRD and TEM showed that the clays are in a disordered state and well dispersed in the polyethylene matrix. Finally, the nanocomposites showed an increase of about 30% in Young's modulus compared with the standard polymer

  5. In situ corrosion monitoring of steam generators

    International Nuclear Information System (INIS)

    An ac electrochemical technique which meets the basic requirements for an in situ localized corrosion monitor within the secondary coolant of PWR steam generators has been investigated. The technique uses two electrodes to measure the electrochemical impedance of a surface in an occluded region with high heat flux. The impedance is related to the kinetics of corrosion. Marked decreases indicate the onset of a high corrosion rate. Experiments have demonstrated the ability of the technique to determine the onset of corrosion under conditions of high solution resistance and solution agitation due to local boiling. Experiments have shown the technique operates similarly in pressurized 3000C water, 1,400 ppM in Na2SO4

  6. In situ corrosion monitoring of steam generators

    International Nuclear Information System (INIS)

    An a.c. electrochemical technique that meets the basic requirements for an in situ localized corrosion monitor within the secondary coolant of PWR steam generators has been investigated. The technique uses two electrodes to measure the electrochemical impedance of a surface in an occluded region with high heat flux. This impedance is related to the kinetics of corrosion and marked decreases indicate the onset of a high corrosion rate. Experiments have demonstrated the ability of the technique to determine the onset of corrosion under conditions of high solution resistance and solution agitation due to local boiling. The technique operates similarly in pressurized 3000C water containing 1400 ppm Na2SO4. (author)

  7. In situ soil remediation: Bacteria or fungi?

    International Nuclear Information System (INIS)

    Contamination of the environment is not a new problem. For most of recorded history, the unwanted byproducts of industrial and residential processes have been dumped into unlined pits or nearby streams. Although disposal techniques have greatly improved, significant quantities of hazardous materials are still being released to the environment via accidental spills and leaking underground storage tanks. One particular group of contaminants of critical environmental concern is polycyclic aromatic hydrocarbons (PAHs). PAH-contaminated sites typically cover large areas; therefore, the development of in situ remediation techniques such as bioremediation is strongly emphasized. In situations when inherent microorganisms are not capable of degrading the contaminants, foreign strains must be used. Bioremediation experiments were conducted to compare the remediation efficiencies of a bacteria and a fungus for an industrially PAH contaminated soil. Specifically, the use of three supplemental nutrient solutions were investigated in conjunction with the bacteria Achromobacter sp. and fungus Cunninghamella echinulata var. elegans

  8. Expérimentation in situ : principes et perspectives

    Directory of Open Access Journals (Sweden)

    Olivier Geffard, Benoit Ferrari, Arnaud Chaumot et Bernard Montuelle

    2010-05-01

    Full Text Available Identifier l'origine d'une perturbation, discriminer un stress physique ou chimique, et quantifier les liens de cause à effet des pollutions supposent de recueillir des données nécessaires à l'évaluation de la qualité des eaux. À l'heure actuelle, la majorité des données est issue de tests de laboratoire, obtenue dans un cadre très contrôlé. Les données recueillies dans les conditions naturelles sont très parcellaires et encore peu répandues même si leur développement serait extrêmement utile. Quels sont les principes de ces expérimentations in situ, leur intérêt, dans quelle mesure peuvent-elles être déployées à une large échelle ? Les auteurs font le point sur ces questions.

  9. Guiding neuronal development with in situ microfabrication

    Science.gov (United States)

    Kaehr, Bryan; Allen, Richard; Javier, David J.; Currie, John; Shear, Jason B.

    2004-11-01

    We report the ability to modify microscopic 3D topographies within dissociated cultures, providing a means to alter the development of neurons as they extend neurites and establish interconnections. In this approach, multiphoton excitation is used to focally excite noncytotoxic photosensitizers that promote protein crosslinking, such as BSA, into matrices having feature sizes 250 nm. Barriers, growth lanes, and pinning structures comprised of crosslinked proteins are fabricated under conditions that do not compromise the viability of neurons both on short time scales and over periods of days. In addition, the ability to fabricate functional microstructures from crosslinked avidin enables submicrometer localization of controllable quantities of biotinylated ligands, such as indicators and biological effectors. Feasibility is demonstrated for using in situ microfabrication to guide the contact position of cortical neurons with micrometer accuracy, opening the possibility for engineering well defined sets of synaptic interactions. biofabrication | multiphoton cell patterning | growth cone

  10. In situ investigations at Avery Island

    International Nuclear Information System (INIS)

    Descriptions and representative data are given for the in situ investigations being performed in the Avery Island Mine. Sufficient detail is presented such that investigators can judge whether any of the studies being performed would be valuable for their numerical modeling exercises. The basic investigations being performed include heater tests, brine migration experiments, and flatjack tests. The heater tests consist of the emplacement of single simulated waste canisters with different power levels. The bulk thermal and mechanical response is measured of the salt surrounding the emplacement. The brine migration studies involve the measurement of moisture inflow into heated boreholes. The flatjack studies are an investigation of the deformation of the borehole when subjected to controlled boundary conditions of stress and temperature

  11. In situ preparation of calcium carbonate films

    International Nuclear Information System (INIS)

    The in situ preparation of calcium carbonate films in an ultra high vacuum (UHV) is inhibited by the decomposition of CO2 molecules at the surface and the absence of CO2 bulk diffusion. Therefore, it is not possible to prepare such films simply by CO2 exposure to a calcium layer. We investigated different approaches for the preparation of CaCO3 films in an UHV. Among these, only the simultaneous evaporation of Ca atoms in a mixed O2 and CO2 atmosphere is able to produce well defined stoichiometric calcium carbonate films. Metastable Induced Electron Spectroscopy, Ultraviolet Photoelectron Spectroscopy and X-ray Photoelectron Spectroscopy are employed to verify quality and purity of the films.

  12. In situ preparation of Calcium hydroxide films

    International Nuclear Information System (INIS)

    The in situ preparation of Calcium hydroxide films in an ultra high vacuum (UHV) is constrained by the decomposition of species at the surface and the absence of OH bulk diffusion. Therefore, it is not possible to prepare such films simply by water exposure to a Calcium layer. We present four different approaches for the preparation of Ca(OH)2 films in an UHV. Two of these methods are found to be ineffective for the preparation, the other two are shown to produce Calcium hydroxide films. Both of the two effective procedures make use of H2 gas exposure. Metastable Induced Electron Spectroscopy, Ultraviolet Photoelectron Spectroscopy, and X-ray Photoelectron Spectroscopy are employed to verify quality and purity of the films.

  13. In situ preparation of Calcium hydroxide films

    Energy Technology Data Exchange (ETDEWEB)

    Dahle, S.; Voigts, F. [Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Maus-Friedrichs, W., E-mail: w.maus-friedrichs@pe.tu-clausthal.de [Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Clausthaler Zentrum fuer Materialtechnik, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany)

    2011-10-31

    The in situ preparation of Calcium hydroxide films in an ultra high vacuum (UHV) is constrained by the decomposition of species at the surface and the absence of OH bulk diffusion. Therefore, it is not possible to prepare such films simply by water exposure to a Calcium layer. We present four different approaches for the preparation of Ca(OH){sub 2} films in an UHV. Two of these methods are found to be ineffective for the preparation, the other two are shown to produce Calcium hydroxide films. Both of the two effective procedures make use of H{sub 2} gas exposure. Metastable Induced Electron Spectroscopy, Ultraviolet Photoelectron Spectroscopy, and X-ray Photoelectron Spectroscopy are employed to verify quality and purity of the films.

  14. In situ preparation of calcium carbonate films

    Energy Technology Data Exchange (ETDEWEB)

    Dahle, S. [Clausthaler Zentrum fuer Materialtechnik, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Voigts, F. [Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Maus-Friedrichs, W., E-mail: w.maus-friedrichs@pe.tu-clausthal.de [Clausthaler Zentrum fuer Materialtechnik, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany); Institut fuer Physik und Physikalische Technologien, Technische Universitaet Clausthal, Leibnizstrasse 4, 38678 Clausthal-Zellerfeld (Germany)

    2012-01-01

    The in situ preparation of calcium carbonate films in an ultra high vacuum (UHV) is inhibited by the decomposition of CO{sub 2} molecules at the surface and the absence of CO{sub 2} bulk diffusion. Therefore, it is not possible to prepare such films simply by CO{sub 2} exposure to a calcium layer. We investigated different approaches for the preparation of CaCO{sub 3} films in an UHV. Among these, only the simultaneous evaporation of Ca atoms in a mixed O{sub 2} and CO{sub 2} atmosphere is able to produce well defined stoichiometric calcium carbonate films. Metastable Induced Electron Spectroscopy, Ultraviolet Photoelectron Spectroscopy and X-ray Photoelectron Spectroscopy are employed to verify quality and purity of the films.

  15. Complications of laser-in-situ-keratomileusis

    Directory of Open Access Journals (Sweden)

    Sridhar Mittanamalli

    2002-01-01

    Full Text Available Laser-in-situ-keratomileusis (LASIK has become a popular technique of refractive surgery because of lower postoperative discomfort, early visual rehabilitation and decreased postoperative haze. Compared to photorefractive keratectomy (PRK, LASIK involves an additional procedure of creating a corneal flap. This may result in complications related to the flap, interface and underlying stromal bed. The common flap-related complications include thin flap, button holing, free caps, flap dislocation and flap striae. The interface complications of diffuse lamellar keratitis, epithelial ingrowth and microbial keratitis are potentially sight threatening. Compared to PRK, there is less inflammation and faster healing after LASIK, but there is a longer period of sensory denervation leading to the complication of dry eyes. The refractive complications include undercorrection, regression, irregular astigmatism, decentration and visual aberrations. Honest and unbiased reporting is important to understand the aetiology and redefine the management.

  16. Reverse osmosis membrane allows in situ regeneration

    International Nuclear Information System (INIS)

    The use of mineral membranes on metallic supports has provided a novel solution to the problem of filtration by the reverse osmosis process. A new reverse osmosis membrane is described which is capable of resisting high operational temperatures (1200C), fluctuations in pH(3 to 12) and high pressure (100 bar), as well as significant chlorine concentrations. In addition, the membrane can be regenerated in-situ on the same porous metal support. Numerous membranes can thus be used over the multi-year life of the porous support. Moreover, accidental damage to the membrane is of no great consequence as the membrane itself can be easily replaced. The life of the installation can thus be extended and the overall cost of filtration reduced. The membrane's various applications include water and effluent treatment in the nuclear power industry. (author)

  17. In situ PEM fuel cell water measurements

    Energy Technology Data Exchange (ETDEWEB)

    Borup, Rodney L [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Davey, John R [Los Alamos National Laboratory; Spendalow, Jacob S [Los Alamos National Laboratory

    2008-01-01

    Efficient PEM fuel cell performance requires effective water management. The materials used, their durability, and the operating conditions under which fuel cells run, make efficient water management within a practical fuel cell system a primary challenge in developing commercially viable systems. We present experimental measurements of water content within operating fuel cells. in response to operational conditions, including transients and freezing conditions. To help understand the effect of components and operations, we examine water transport in operating fuel cells, measure the fuel cell water in situ and model the water transport within the fuel cell. High Frequency Resistance (HFR), AC Impedance and Neutron imaging (using NIST's facilities) were used to measure water content in operating fuel cells with various conditions, including current density, relative humidity, inlet flows, flow orientation and variable GDL properties. Ice formation in freezing cells was also monitored both during operation and shut-down conditions.

  18. PERFORMANCE CONFIRMATION IN-SITU INSTRUMENTATION

    International Nuclear Information System (INIS)

    The purpose of this document is to identify and analyze the types of in-situ instruments and methods that could be used in support of the data acquisition portion of the Performance Confirmation (PC) program at the potential nuclear waste repository at Yucca Mountain. The PC program will require geomechanical , geophysical, thermal, and hydrologic instrumentation of several kinds. This analysis is being prepared to document the technical issues associated with each type of measurement during the PC period. This analysis utilizes the ''Performance Confirmation Input Criteria'' (CRWMS M andO 1999a) as its starting point. The scope of this analysis is primarily on the period after the start of waste package emplacement and before permanent closure of the repository, a period lasting between 15 and 300 years after last package emplacement (Stroupe 2000, Attachment 1, p. 1). The primary objectives of this analysis are to: (1) Review the design criteria as presented in the ''Performance Confirmation Input Criteria'' (CRWMS M andO 1999a). The scope of this analysis will be limited to the instrumentation related to parameters that require continuous monitoring of the conditions underground. (2) Preliminary identification and listing of the data requirements and parameters as related to the current repository layout in support of PC monitoring. (3) Preliminary identification of methods and instrumentation for the acquisition of the required data. Although the ''Performance Confirmation Input Criteria'' (CRWMS M andO 1999a) defines a broad range of data that must be obtained from a variety of methods, the focus of this analysis is on instrumentation related to the performance of the rock mass and the formation of water in the repository environment, that is obtainable from in-situ observation, testing, and monitoring

  19. In Situ Field Testing of Processes

    Energy Technology Data Exchange (ETDEWEB)

    J. Wang

    2001-12-14

    The purpose of this Analysis/Model Report (AMR) is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts of the Yucca Mountain Site Characterization Project (YMP). This revision updates data and analyses presented in the initial issue of this AMR. This AMR was developed in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' and ''Technical Work Plan for UZ Flow, Transport, and Coupled Processes Process Model Report. These activities were performed to investigate in situ flow and transport processes. The evaluations provide the necessary framework to: (1) refine and confirm the conceptual model of matrix and fracture processes in the unsaturated zone (UZ) and (2) analyze the impact of excavation (including use of construction water and effect of ventilation) on the UZ flow and transport processes. This AMR is intended to support revisions to ''Conceptual and Numerical Models for UZ Flow and Transport'' and ''Unsaturated Zone Flow and Transport Model Process Model Report''. In general, the results discussed in this AMR are from studies conducted using a combination or a subset of the following three approaches: (1) air-injection tests, (2) liquid-release tests, and (3) moisture monitoring using in-drift sensors or in-borehole sensors, to evaluate the impact of excavation, ventilation, and construction-water usage on the surrounding rocks. The liquid-release tests and air-injection tests provide an evaluation of in situ fracture flow and the competing processes of matrix imbibition. Only the findings from testing and data not covered in the ''Seepage Calibration Model and Seepage Testing Data'' are analyzed in detail in the AMR.

  20. PERFORMANCE CONFIRMATION IN-SITU INSTRUMENTATION

    Energy Technology Data Exchange (ETDEWEB)

    N.T. Raczka

    2000-05-23

    The purpose of this document is to identify and analyze the types of in-situ instruments and methods that could be used in support of the data acquisition portion of the Performance Confirmation (PC) program at the potential nuclear waste repository at Yucca Mountain. The PC program will require geomechanical , geophysical, thermal, and hydrologic instrumentation of several kinds. This analysis is being prepared to document the technical issues associated with each type of measurement during the PC period. This analysis utilizes the ''Performance Confirmation Input Criteria'' (CRWMS M&O 1999a) as its starting point. The scope of this analysis is primarily on the period after the start of waste package emplacement and before permanent closure of the repository, a period lasting between 15 and 300 years after last package emplacement (Stroupe 2000, Attachment 1, p. 1). The primary objectives of this analysis are to: (1) Review the design criteria as presented in the ''Performance Confirmation Input Criteria'' (CRWMS M&O 1999a). The scope of this analysis will be limited to the instrumentation related to parameters that require continuous monitoring of the conditions underground. (2) Preliminary identification and listing of the data requirements and parameters as related to the current repository layout in support of PC monitoring. (3) Preliminary identification of methods and instrumentation for the acquisition of the required data. Although the ''Performance Confirmation Input Criteria'' (CRWMS M&O 1999a) defines a broad range of data that must be obtained from a variety of methods, the focus of this analysis is on instrumentation related to the performance of the rock mass and the formation of water in the repository environment, that is obtainable from in-situ observation, testing, and monitoring.

  1. In Situ Field Testing of Processes

    International Nuclear Information System (INIS)

    The purpose of this Analysis/Model Report (AMR) is to update and document the data and subsequent analyses from ambient field-testing activities performed in underground drifts of the Yucca Mountain Site Characterization Project (YMP). This revision updates data and analyses presented in the initial issue of this AMR. This AMR was developed in accordance with the ''Technical Work Plan for Unsaturated Zone (UZ) Flow and Transport Process Model Report'' and ''Technical Work Plan for UZ Flow, Transport, and Coupled Processes Process Model Report. These activities were performed to investigate in situ flow and transport processes. The evaluations provide the necessary framework to: (1) refine and confirm the conceptual model of matrix and fracture processes in the unsaturated zone (UZ) and (2) analyze the impact of excavation (including use of construction water and effect of ventilation) on the UZ flow and transport processes. This AMR is intended to support revisions to ''Conceptual and Numerical Models for UZ Flow and Transport'' and ''Unsaturated Zone Flow and Transport Model Process Model Report''. In general, the results discussed in this AMR are from studies conducted using a combination or a subset of the following three approaches: (1) air-injection tests, (2) liquid-release tests, and (3) moisture monitoring using in-drift sensors or in-borehole sensors, to evaluate the impact of excavation, ventilation, and construction-water usage on the surrounding rocks. The liquid-release tests and air-injection tests provide an evaluation of in situ fracture flow and the competing processes of matrix imbibition. Only the findings from testing and data not covered in the ''Seepage Calibration Model and Seepage Testing Data'' are analyzed in detail in the AMR

  2. In situ X-ray diffraction of oxide scales on high-temperature materials; In-situ-Roentgenbeugung von Oxidschichten auf Hochtemperaturwerkstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Gross, M.

    1999-07-01

    The subject of this dissertation is examination of high-temperature oxidation processes primarily by in situ X-ray diffraction, accompanied by metallographic and microprobe analyses. The studies reported focus on two major aspects: Time and temperature-resolved investigation of the behaviour of nickel-base alloys intended for use as turbine blade materials, as some of the processes contributing to their complex oxidation behaviour can only be revealed by in situ analysis; and temperature-resolved detection of mechanical stresses in oxide scales. For this last task, a novel parallel-ray optics with a Goebel mirror was used, in order to avoid measuring errors due to the high-temperature system conditions. The nickel-base alloys DS CM247 LC and CMSX4 were examined for their oxidation behaviour because they are candidate materials of interest to the gas turbine industry. The stress analyses were performed with the iron-base alloy PM 2000 prepared by powder metallurgy, because oxidation processes on PM 2000 form a homogeneous {alpha}-Al{sub 2}O{sub 3} layer as from 1000 C upward, thus offering good prospects for gaining enhanced insight into the processes involved, and for further developing the methodology for in situ stress analysis. (orig./CB) [German] Ziel dieser Arbeit war die Untersuchung von Hochtemperaturoxidationsvorgaengen vor allem mit in situ Roentgenbeugung, die durch metallographische Analysen und Mikrosondenuntersuchungen ergaenzt wurde. Dabei wurden zwei Schwerpunkte gewaehlt. Der eine Schwerpunkt lag auf zeit- und temperaturaufgeloesten Studien bei Nickelbasissuperlegierungen fuer die Anwendung als Turbinenschaufelwerkstoff, deren komplexes Oxidationsverhalten in manchen Aspekten nur mit in situ Methoden zu bestimmen war. Der zweite Schwerpunkt lag auf der temperaturaufgeloesten Erfassung mechanischer Spannungen in Oxidschichten. In diesem Schwerpunkt kam eine neuartige Parallelstrahloptik mit Goebelspiegel zum Einsatz, zur Vermeidung von Messfehlern verursacht durch die Hochtemperaturanordnung. Im ersten Schwerpunkt wurden das Oxidationsverhalten der Turbinenschaufelwerkstoffe DS CM247 LC und CMSX4 untersucht, an dessen Kenntnis von Seiten der Gasturbinenhersteller Interesse besteht. Die Spannungsuntersuchungen des zweiten Schwerpunkts erfolgten an der pulvermetallurgisch hergestellten Eisenbasislegierung PM 2000. Da PM 2000 ab 1000 C eine homogene {alpha}-Al{sub 2}O{sub 3}-Schicht bildet, bot es die Voraussetzungen zur methodischen Weiterentwicklung in den Bereich der in situ Spannungsuntersuchungen. (orig.)

  3. Superconducting proximity effect for in situ and model layered systems

    International Nuclear Information System (INIS)

    Large-scale magnets in the 8- to 14-tesla range can be prepared using in situ composites fabricated on a commercial scale. The main drawback for using in situ materials is that AC losses are higher than from mechanically produced multifilamentary wire, due to more tight coupling of filaments, because the average spacing between fibers is comparable to superconducting pair potential decay length

  4. Successful Treatment of Lower Eyelid Melanoma in Situ

    Directory of Open Access Journals (Sweden)

    Andrew A. Gassman, MD

    2014-05-01

    Full Text Available Summary: We present a brief literature review of the topical immune-modulating medication Imiquimod. The treatment of periorbital melanoma in situ typically requires surgical resection. Here we discuss a case of lower eyelid melanoma in situ successfully treated non-operatively with Imiquimod.

  5. Some implications of in situ uranium mining technology development

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, C.E.; Parkhurst, M.A.; Cole, R.J.; Keller, D.; Mellinger, P.J.; Wallace, R.W.

    1980-09-01

    A technology assessment was initiated in March 1979 of the in-situ uranium mining technology. This report explores the impediments to development and deployment of this technology and evaluates the environmental impacts of a generic in-situ facility. The report is divided into the following sections: introduction, technology description, physical environment, institutional and socioeconomic environment, impact assessment, impediments, and conclusions. (DLC)

  6. Some implications of in situ uranium mining technology development

    International Nuclear Information System (INIS)

    A technology assessment was initiated in March 1979 of the in-situ uranium mining technology. This report explores the impediments to development and deployment of this technology and evaluates the environmental impacts of a generic in-situ facility. The report is divided into the following sections: introduction, technology description, physical environment, institutional and socioeconomic environment, impact assessment, impediments, and conclusions

  7. Zebrafish Whole-Mount In Situ Hybridization Followed by Sectioning

    DEFF Research Database (Denmark)

    Doganli, Canan; Nyengaard, Jens Randel; Lykke-Hartmann, Karin

    2016-01-01

    In situ hybridization is a powerful technique used for locating specific nucleic acid targets within morphologically preserved tissues and cell preparations. A labeled RNA or DNA probe hybridizes to its complementary mRNA or DNA sequence within a sample. Here, we describe RNA in situ hybridization protocol for whole-mount zebrafish embryos.

  8. IN-SITU TRITIUM BETA DETECTOR

    International Nuclear Information System (INIS)

    The objectives of this three-phase project were to design, develop, and demonstrate a monitoring system capable of detecting and quantifying tritium in situ in ground and surface waters, and in water from effluent lines prior to discharge into public waterways. The tritium detection system design is based on measurement of the low energy beta radiation from the radioactive decay of tritium using a special form of scintillating optical fiber directly in contact with the water to be measured. The system consists of the immersible sensor module containing the optical fiber, and an electronics package, connected by an umbilical cable. The system can be permanently installed for routine water monitoring in wells or process or effluent lines, or can be moved from one location to another for survey use. The electronics will read out tritium activity directly in units of pico Curies per liter, with straightforward calibration. In Phase 1 of the project, we characterized the sensitivity of fluor-doped plastic optical fiber to tritium beta radiation. In addition, we characterized the performance of photomultiplier tubes needed for the system. In parallel with this work, we defined the functional requirements, target specifications, and system configuration for an in situ tritium beta detector that would use the fluor-doped fibers as primary sensors of tritium concentration in water. The major conclusions from the characterization work are: A polystyrene optical fiber with fluor dopant concentration of 2% gave best performance. This fiber had the highest dopant concentration of any fibers tested. Stability may be a problem. The fibers exposed to a 22-day soak in 120 F water experienced a 10x reduction in sensitivity. It is not known whether this was due to the build up of a deposit (a potentially reversible effect) or an irreversible process such as leaching of the scintillating dye. Based on the results achieved, it is premature to initiate Phase 2 and commit to a prototype design for construction and test. Significant improvements must be made in fluor-doped fiber performance in order to use the method for in situ monitoring to verify compliance with current EPA drinking water standards. Additional Phase 1 fiber development work should be performed to increase the fluor dopant concentration above 2% until the self-absorption limit is observed. Continued fiber optimization work is expected to improve the sensitivity limits, and will enable application of the detector to verify compliance with the US EPA drinking water standard of 20,000 pico Curies per liter. However, if the need for monitoring higher levels of tritium in water at concentrations greater than 200,000 pico Curies per liter is justified, then prototype development and testing could proceed either as a Phase 2 stand-alone effort or in parallel with continued Phase 1 development work

  9. Multimodal confocal mosaics enable high sensitivity and specificity in screening of in situ squamous cell carcinoma

    Science.gov (United States)

    Grados Luyando, Maria del Carmen; Bar, Anna; Snavely, Nicholas; Jacques, Steven; Gareau, Daniel S.

    2014-02-01

    Screening cancer in excision margins with confocal microscopy may potentially save time and cost over the gold standard histopathology (H and E). However, diagnostic accuracy requires sufficient contrast and resolution to reveal pathological traits in a growing set of tumor types. Reflectance mode images structural details due to microscopic refractive index variation. Nuclear contrast with acridine orange fluorescence provides enhanced diagnostic value, but fails for in situ squamous cell carcinoma (SCC), where the cytoplasm is important to visualize. Combination of three modes [eosin (Eo) fluorescence, reflectance (R) and acridine orange (AO) fluorescence] enable imaging of cytoplasm, collagen and nuclei respectively. Toward rapid intra-operative pathological margin assessment to guide staged cancer excisions, multimodal confocal mosaics can image wide surgical margins (~1cm) with sub-cellular resolution and mimic the appearance of conventional H and E. Absorption contrast is achieved by alternating the excitation wavelength: 488nm (AO fluorescence) and 532nm (Eo fluorescence). Superposition and false-coloring of these modes mimics H and E, enabling detection of the carcinoma in situ in the epidermal layer The sum mosaic Eo+R is false-colored pink to mimic eosins' appearance in H and E, while the AO mosaic is false-colored purple to mimic hematoxylins' appearance in H and E. In this study, mosaics of 10 Mohs surgical excisions containing SCC in situ and 5 containing only normal tissue were subdivided for digital presentation equivalent to 4X histology. Of the total 16 SCC in situ multimodal mosaics and 16 normal cases presented, two reviewers made 1 and 2 (respectively) type-2 errors (false positives) but otherwise scored perfectly when using the confocal images to screen for the presence of SCC in situ as compared to the gold standard histopathology. Limitations to precisely mimic H and E included occasional elastin staining by AO. These results suggest that confocal mosaics may effectively guide staged SCC excisions in skin and other tissues.

  10. Detection of denitrification genes by in situ rolling circle amplification - fluorescence in situ hybridization (in situ RCA-FISH) to link metabolic potential with identity inside bacterial cells

    DEFF Research Database (Denmark)

    Hoshino, Tatsuhiko; Schramm, Andreas

    2010-01-01

    A target-primed in situ rolling circle amplification (in situ RCA) protocol was developed for detection of single-copy genes inside bacterial cells and optimized with Pseudomonas stutzeri, targeting nitrite and nitrous oxide reductase genes (nirS and nosZ). Two padlock probes were designed per gene to target both DNA strands; the target DNA was cut by a restriction endonuclease close to the probe binding sites, which subsequently were made accessible by 5'-3' exonucleolysis. After hybridization,...

  11. Autonomous In-Situ Resources Prospector

    Science.gov (United States)

    Dissly, R. W.; Buehler, M. G.; Schaap, M. G.; Nicks, D.; Taylor, G. J.; Castano, R.; Suarez, D.

    2004-01-01

    This presentation will describe the concept of an autonomous, intelligent, rover-based rapid surveying system to identify and map several key lunar resources to optimize their ISRU (In Situ Resource Utilization) extraction potential. Prior to an extraction phase for any target resource, ground-based surveys are needed to provide confirmation of remote observation, to quantify and map their 3-D distribution, and to locate optimal extraction sites (e.g. ore bodies) with precision to maximize their economic benefit. The system will search for and quantify optimal minerals for oxygen production feedstock, water ice, and high glass-content regolith that can be used for building materials. These are targeted because of their utility and because they are, or are likely to be, variable in quantity over spatial scales accessible to a rover (i.e., few km). Oxygen has benefits for life support systems and as an oxidizer for propellants. Water is a key resource for sustainable exploration, with utility for life support, propellants, and other industrial processes. High glass-content regolith has utility as a feedstock for building materials as it readily sinters upon heating into a cohesive matrix more readily than other regolith materials or crystalline basalts. Lunar glasses are also a potential feedstock for oxygen production, as many are rich in iron and titanium oxides that are optimal for oxygen extraction. To accomplish this task, a system of sensors and decision-making algorithms for an autonomous prospecting rover is described. One set of sensors will be located in the wheel tread of the robotic search vehicle providing contact sensor data on regolith composition. Another set of instruments will be housed on the platform of the rover, including VIS-NIR imagers and spectrometers, both for far-field context and near-field characterization of the regolith in the immediate vicinity of the rover. Also included in the sensor suite are a neutron spectrometer, ground-penetrating radar, and an instrumented cone penetrometer for subsurface assessment. Output from these sensors will be evaluated autonomously in real-time by decision-making software to evaluate if any of the targeted resources has been detected, and if so, to quantify their abundance. Algorithms for optimizing the mapping strategy based on target resource abundance and distribution are also included in the autonomous software. This approach emphasizes on-the-fly survey measurements to enable efficient and rapid prospecting of large areas, which will improve the economics of ISRU system approaches. The mature technology will enable autonomous rovers to create in-situ resource maps of lunar or other planetary surfaces, which will facilitate human and robotic exploration.

  12. Raman spectroscopy - in situ characterization of growth and surface processes

    Science.gov (United States)

    Perkins, James Robert

    The goal of this thesis is to expand on the usefulness of Raman spectroscopy as an in situ probe to aid in the growth and implementation of electronic, optical, and biodetection materials. We accomplish this goal by developing two diverse optical characterization projects. In the first project, an autoclave similar to those used in solvothermal growth which has been outfitted with an optical window is used to collect vibrational spectra of solvents and mineralizers commonly used in the ammonothermal growth of gallium nitride. Secondly, novel silver nanowires created by ferroelectric lithography are evaluated by surface enhanced micro-Raman spectroscopy for use as surface enhanced substrates for low detection limit or single molecule bio-detectors. Raman spectroscopy is already a widely accepted method to characterize and identify a wide variety of materials. Vibrational spectra can yield much information on the presence of chemical species as well as information regarding the phase and interactive properties. Because Raman spectroscopy is a generally non-intrusive technique it is ideal for analysis of hazardous or far-from-ambient liquids, gases, or solids. This technique is used in situ to characterize crystal growth and surface enhanced photochemistry. The phenomenon of Surface Enhanced Raman Spectroscopy (SERS) has been observed in many systems but some fundamental understanding is still lacking and the technique has been slow to transition from the laboratory to the industry. Aggregated colloids and lithographically created islands have shown the best success as reproducible substrates for SERS detection. These techniques, however, lack control over shape, size, and position of the metal nanoparticles which leave them reliant on hotspots. Because of the potential for control of the position of aggregates, ferroelectric lithographically created silver nanowires are evaluated as a potential SERS substrate using pyridine, benzoic acid, and Rhodamine 6g. Surface enhancement from these samples varies periodically as excitation light is scanned perpendicular to the wires. The periodicity, however, has the frequency of the positive domains where carbon laser damage is preferentially created. There is a current need for homoepitaxial substrates for gallium nitride devices including light emitting diodes, transistors, and laser diodes. Ammonothermal growth is a promising technique for creating bulk single crystalline GaN, but questions remain concerning the intermediates of reactions in supercritical Ammonia. Neat ammonia and water are monitored by Raman spectroscopy from room temperature to 500°C and 20 kpsi with both UV and visible excitation. In both systems, the amount of hydrogen bonding, which can be determined by O-H and N-H stretch frequency shifts, decreases with increasing temperature. In supercritical ammonia, the degree of Fermi resonance between the nu1 and 2nu4 modes decreases linearly with temperature while a minimum in pyramidal height of the NH3 molecule is reached at moderate pressures. Binary solutions of sodium azide and ammonia are investigated to temperatures which allow observation of the breakdown of the azides. The pressure and N2 Raman signal increase as the azide decomposes to sodium amide and N2 and H2 process gasses. The rate of decrease of the Raman signal of the azide increases as the reaction proceeds suggesting that the reaction rate is proportional to the pressure. The Fermi resonance, hydrogen bonding, and pyramidal height parameters were not affected by the presence of the azide.

  13. In situ radionuclide transfers in the deep-sea Lysianassidae amphipod Eurythenes gryllus

    International Nuclear Information System (INIS)

    Previous studies at the NEA dumpsite confirmed the existence of the scavenging amphipod Eurythenes gryllus. The aim of this study was to inquire if, under deep-sea conditions of low temperature and high pressure, this species of crustacean would retain artificial radionuclides in the same organ as those observed in similar coastal species of the same family. This necrophagous species is easily attracted by bait. It can ingest 30 to 60% of its body weight in 30 ± 10 min. In addition, this species can store ingested food for several weeks. Thus, the ingestion of radiolabelled food over a period of several days could be considered as a single-meal contamination experiment. For all these reasons Eurythenes gryllus appeared to be a good test animal to compare laboratory experiments on coastal species with in situ radionuclide retention studies on deep-sea fauna. In order to prevent any disturbance of their physiological conditions, a special device was used to attract and feed the animals with radiolabelled baits, in situ at a depth of 4000 m, rather than recovering amphipods without decompression and keeping them alive aboard ship. Qualitatively speaking results yielded by in situ experiments support those obtained from laboratory studies with coastal animals and the same radionuclides

  14. Freshening in the South China Sea during 2012 revealed by Aquarius and in situ data

    Science.gov (United States)

    Zeng, Lili; Timothy Liu, W.; Xue, Huijie; Xiu, Peng; Wang, Dongxiao

    2014-12-01

    Newly available sea surface salinity (SSS) data from the Aquarius together with in situ hydrographic data are used to explore the spatial and temporal characteristics of SSS in the South China Sea (SCS). Using in situ observations as the reference, an evaluation of daily Aquarius data indicates that there exists a negative bias of 0.45 psu for the version 3.0 data set. The root-mean-square difference for daily Aquarius SSS is about 0.53 psu after correcting the systematic bias, and those for weekly and monthly Aquarius SSSs are 0.45 and 0.29 psu, respectively. Nevertheless, the Aquarius SSS shows a reliable freshening in the SCS in 2012, which is larger than the Aquarius uncertainty. The freshening of up to 0.4 psu in the upper-ocean of the northern SCS was confirmed by in situ observations. This freshening in 2012 was caused by a combined effect of abundant local freshwater flux and limited Kuroshio intrusion. By comparing the Kuroshio intrusion in 2012 with that in 2011, we found the reduction as a relatively important cause for the freshening over the northern SCS. In contrast to the northern SCS, reduced river discharge in 2012 played the leading role to the saltier surface in the region near the Mekong River mouth with respect to 2011.

  15. 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.

  16. A NOVEL OPHTHALMIC DRUG DELIVERY SYSTEM: IN-SITU GEL

    Directory of Open Access Journals (Sweden)

    A.P. Patil*, A.A. Tagalpallewar, G.M. Rasve, A.V. Bendre, P.G. Khapekar

    2012-09-01

    Full Text Available The ophthalmic in-situ gels now days proved an palpable sustained drug delivery in various eye diseases. The formulation of in-situ gels for eye which carries the advantages like easy for administration, reduces frequency of dose and improves patient compliance. The formation of in-situ gels depends on phase transition system or sol-gel transition system. The formulation approaches like temperature intonation, pH change and presence of ions from which the drug gets released in a sustained and controlled manner are utilised for in-situ gels. Various polymers that are used for the formulation of in-situ gels include chitosan, Pluronic F-127, poly-caprolactone, gellan gum, alginic acid, xyloglucan, pectin etc.

  17. Evaluation of LIDAR/Polarimeter Aerosol Measurements by In Situ Instrumentation during DEVOTE

    Science.gov (United States)

    Beyersdorf, A. J.; Ziemba, L. D.; Anderson, B. E.; Dolgos, G.; Ottaviani, M.; Obland, M. D.; Rogers, R.; Thornhill, K. L.; Winstead, E. L.; Yang, M. M.; Hair, J. W.

    2011-12-01

    Combined measurements from LIDAR (LIght Detection And Ranging) and polarimeter instruments provide the opportunity for enhanced satellite observations of aerosol properties including retrievals of aerosol optical depth, single scattering albedo, effective radius, and refractive index. However, these retrievals (specifically for refractive index) have not been fully vetted and require additional intercomparisons with in situ measurements to improve accuracy. Proper validation of these combined LIDAR/polarimeter retrievals requires evaluation in varying atmospheric conditions and of varying aerosol composition. As part of this effort, two NASA Langley King Air aircraft have been outfitted to provide coordinated measurements of aerosol properties. One will be used as a remote sensing platform with the NASA Langley high-spectral resolution LIDAR (HSRL) and NASA GISS research scanning polarimeter (RSP). The second aircraft has been modified for use as an in situ platform and will house a suite of aerosol microphysical instrumentation, a pair of diode laser hygrometers (DLHs) for water vapor and cloud extinction measurements, and a polarized imaging nephelometer (PI-Neph). The remote sensing package has flown in a variety of campaigns, however only rarely has been able to coordinate with in situ measurements. The use of two collocated aircraft will allow for future coordinated flights to provide a more complete dataset for evaluation of aerosol retrievals and allow for fast-response capability. Results from the first coordinated King Air flights as part of DEVOTE (Development and Evaulation of satellite ValidatiOn Tools by Experimenters) will be presented. Flights are planned out of Hampton, VA during September and October 2011 including underflights of the CALIPSO satellite and overflights of ground-based AERONET (AErosol RObotic NETwork) sites. These will provide a comparison of aerosol properties between in situ and remote instruments (ground, aircraft, and satellite-based). In situ measurements include aerosol number density, size, scattering, absorption and hygroscopicity (aerosol scattering as a function of relative humidity). The PI-Neph will provide the first airborne in situ measurements of aerosol polarized phase function for comparison to the RSP retrievals. As this is the first airborne use of the PI-Neph, aerosol scattering measurements from the PI-Neph will be compared to an integrating nephelometer to provide a primary indication of instrument functionality. Specific flights will be performed to study a range of aerosol classifications including fresh anthropogenic pollution (flights over populated regions), aged pollution (tracking pollution as it moves off shore), sea salt (low altitude ocean flights by the in situ aircraft) and biogenic (flights over forest canopies). In addition, the DLH and a wing-mounted cloud aerosol precipitation spectrometer will provide insight into aerosol retrievals above and near clouds.

  18. Association of Serpulina hyodysenteriae with the colonic mucosa in experimental swine dysentery studied by fluorescent in situ hybridization

    DEFF Research Database (Denmark)

    Jensen, Tim Kåre; Boye, Mette; Møller, Kristian; Leser, T. D.; Jorsal, Sven Erik Lind

    1998-01-01

    The localization of Serpulina hyodysenteriae in experimental swine dysentery was studied by fluorescent in situ hybridization (FISH) using an oligonucleotide probe targeting the 23S rRNA of S. hyodysenteriae. Nine 8-week-old pigs were challenged. Seven of the pigs were intragastrically dosed with 1x10(9) cfu S. hyodysenteriae for 3 consecutive days, whereas two pigs were infected by contact. Six non-challenged pigs served as negative controls. The challenged pigs developed clinical swine dysente...

  19. Preparation and thermal properties of mesoporous silica/phenolic resin nanocomposites via in situ polymerization

    Directory of Open Access Journals (Sweden)

    J. Lv

    2012-10-01

    Full Text Available In order to enhance the adhesion between inorganic particles and polymer matrix, in this paper, the mesoporous silica SBA-15 material was synthesized by the sol-gel method. The surface of SBA-15 was modified using ?-glycidyloxypropyltrimethoxysilane (GOTMS as a coupling agent, and then mesoporous silica/phenolic resin (SBA-15/PF nanocomposites were prepared via in situ polymerization. The structural parameters and physical properties of SBA-15, SBA-15-GOTMS (SBA-15 surface treated using GOTMS as coupling agents and E-SBA-15/PF (SBA-15/PF nanocomposites extracted using ethanol as solvent were characterized by X-ray diffraction (XRD, N2 adsorption-desorption, Fourier transform infrared spectroscopy (FTIR, scanning electron microscopy (SEM, transmission electron microscopy (TEM and thermogravimetric analysis (TGA. The thermal properties of the nanocomposites were studied by differential scanning calorimetry (DSC and thermogravimetric analysis (TGA. The results demonstrated that the GOTMS were successfully grafted onto the surface of SBA-15, and chemical bonds between PF and SBA-15-GOTMS were formed after in situ polymerization. In addition, it is found that the in situ polymerization method has great effects on the textural parameters of SBA-15. The results also showed that the glass transition temperatures and thermal stability of the PF nanocomposites were obviously enhanced as compared with the pure PF at silica contents between 1–3 wt%, due to the uniform dispersion of the modified SBA-15 in the matrix.

  20. In-situ electrochemical route to aerogel electrode materials of graphene and hexagonal CeO?.

    Science.gov (United States)

    Chen, Kunfeng; Xue, Dongfeng

    2015-05-15

    We reported a one-step in-situ electrochemical route to synthesize 3D aerogel electrode materials including graphene and hexagonal CeO2 composites. The graphene/CeO2 aerogel can be formed via freeze-drying graphene/CeO2 colloidal solution that was obtained by electrochemical exfoliation of graphite anode and in-situ deposition of CeO2 nanoparticles on graphene sheets in mixing electrolyte of (NH4)2SO4/Ce(NO3)3 and (NH4)2SO4/(NH4)2Ce(NO3)6. The as-obtained CeO2 nanoparticles were closely contacted with graphene, which can enhance the synergistic effect between graphene and CeO2. It is interesting that the as-obtained CeO2 products possessed hexagonal crystal structure that was rarely reported. The Faradaic reactivity of the graphene/CeO2 composites as supercapacitor was enhanced with the increase of the concentration of Ce salts in initial electrolyte. The introduction of CeO2 to graphene electrode can lead to the presence of additional pseudocapacitance besides the electric double-layer capacitance. This simple one-step in-situ electrochemical route can be extended to synthesize various graphene/metal oxide aerogel electrode materials for electric energy storage. PMID:25660707

  1. Development of an rRNA-targeted oligonucleotide probe specific for the genus Acinetobacter and its application for in situ monitoring in activated sludge.

    OpenAIRE

    Wagner, M.; Erhart, R; Manz, W; Amann, R; Lemmer, H; Wedi, D; Schleifer, K H

    1994-01-01

    Enhanced biological phosphate removal in an anaerobic-aerobic activated sludge system has generally been ascribed to members of the genus Acinetobacter. A genus-specific 16S rRNA-targeted oligonucleotide probe was developed to investigate the role of Acinetobacter spp. in situ. Nonisotopic dot blot hybridization to 66 reference strains, including the seven described Acinetobacter spp., demonstrated the expected probe specificity. Fluorescent derivatives were used for in situ monitoring of Aci...

  2. Innovative technologies for in-situ remediation

    International Nuclear Information System (INIS)

    LLNL is developing several innovative remediation technologies as long-term improvements to the current pump and treat approaches to cleaning up contaminated soils and groundwater. These technologies include dynamic underground stripping, in-situ microbial filters, and remediation using bremsstrahlung radiation. Concentrated underground organic contaminant plumes are one of the most prevalent groundwater contamination sources. The solvent or fuel can percolate deep into the earth, often into water-bearing regions. Collecting as a separate, liquid organic phase called dense non-aqueous-phase liquids (DNAPLs), or light NAPLs (LNAPLs), these contaminants provide a source term that continuously compromises surrounding groundwater. This type of spill is one of the most difficult environmental problems to remediate. Attempts to remove such material requires a huge amount of water which must be washed through the system to clean it, requiring decades. Traditional pump and treat approaches have not been successful. LLNL has developed several innovative technologies to clean up NAPL contamination. Detailed descriptions of these technologies are given

  3. Backfilling of deposition tunnels, in situ alternative

    International Nuclear Information System (INIS)

    The backfilling process described in this report is based on in situ compaction of a mixture of bentonite and ballast (30:70) into the deposition tunnel. This method has been tested in practice in various field tests by SKB, most recently in the Prototype repository test performed at Aespoe HRL. The backfill mixture is prepared above ground and transported to the repository level with a tank truck. The material is compacted into layers with an inclination of 35 deg C and a thickness of approximately 20 cm. The compaction is performed with a vibratory plate attached to a boom of an excavator. In order to keep up with the required canister installation rate determined for the Finnish repository, at least 13 layers need to be compacted daily. This means working in 2-3 shifts on the working days that are available for backfilling operations. The dry densities achieved in field tests for the wall/roof section of the backfill have been insufficient compared with the dry density criteria set for the backfill. In theory, it may be possible to reach dry densities that fulfil the criteria, although with a relatively small safety margin. Another open issue is whether the mixture of bentonite and ballast has sufficient self-healing ability to seal-off erosion channels after the tunnels have been closed and the backfill has reached full saturation. (orig.)

  4. In situ produced hydrogen (hydrogen on demand)

    Energy Technology Data Exchange (ETDEWEB)

    Morris, John [Syringa Bioscience (Pty) Ltd, 137 Edward Avenue, Hennops Park, Centurion 0157 (South Africa); Radu, Marin [Centrul de Cercetari pentru Materiale Macromoleculare si Membrane - CCMMM, 202B, Splaiul Independentei, Sector 6, 060023, Bucuresti (Romania)

    2010-07-15

    Pollution created by the increased number of people and by industrial and domestic activities put pressure in the planet's climate that can result in a catastrophe which may end the humans' life on the planet. Hydrogen is an endless source of energy, clean and efficient, which exist in the Universe in a high proportion, over 88%. Current problems that stop the development of an efficient Hydrogen Economy are the high production costs, storage problems, and transport and supply problems, due to the high cost of operational structure needed for supply to the end user. To all these objective reasons may be added the high rate of international terrorism that may use storage of liquid hydrogen as a target for its activity. Looking in the right direction, Marin Radu solved the above problems by producing hydrogen in situ, via an electro-catalytic membrane, which decomposes the water molecules efficiently, with low input of electric current (9 V-24 V) and produces hydrogen on demand [. unpublished]. (author)

  5. [Fluorescence in situ hybridization on histologic sections].

    Science.gov (United States)

    Mrhalová, Marcela; Kodet, Roman

    2013-10-01

    I-FISH (fluorescence in situ hybridization on interphasic nuclei) represents a laboratory method linking morphological investigations (histological sections of formaldehyde fixed and paraffin embedded tissues) with molecular techniques (sequence specificity of nucleic acids bases for a certain locus). I-FISH is relatively undemanding for a laboratory workout, but offering a lot of important information about the investigated cells. Within a scope of pathology departments I-FISH is utilized mostly in diagnostics of neoplasms. I-FISH is helpful in detecting gene copy numbers (amplifications or deletions), and, importantly, in establishing copy numbers of individual chromosomes (polysomies or monosomies), chromosomal breaks and translocations. At present, I-FISH is used not only for diagnosis and estimation of prognosis, but also as a method to qualify a patient for a targeted biological therapy. Because demands on investigation of solid tumors keep raising I-FISH becomes a part of routine investigations. The aim of this paper is to summarize principles and the utility of I-FISH and to help the interested readers in finding a basic orientation in this laboratory method. PMID:24289480

  6. Cubesat in-situ degradation detector (CIDD)

    Science.gov (United States)

    Rievers, Benny; Milke, Alexander; Salden, Daniel

    2015-07-01

    The design of the thermal control and management system (TCS) is a central task in satellite design. In order to evaluate and dimensionize the properties of the TCS, material parameters specifying the conductive and radiative properties of the different TCS components have to be known including their respective variations within the mission lifetime. In particular the thermo-optical properties of the outer surfaces including critical TCS components such as radiators and thermal insulation are subject to degradation caused by interaction with the space environment. The evaluation of these material parameters by means of ground testing is a time-consuming and expensive endeavor. Long-term in-situ measurements on board the ISS or large satellites not only realize a better implementation of the influence of the space environment but also imply high costs. Motivated by this we propose the utilization of low-cost nano-satellite systems to realize material tests within space at a considerably reduced cost. We present a nanosat-scale degradation sensor concept which realizes low power consumption and data rates compatible with nanosat boundaries at UHF radio. By means of a predefined measurement and messaging cycle temperature curves are measured and evaluated on ground to extract the change of absorptivity and emissivity over mission lifetime.

  7. IN-SITU MINING OF PHOSPHATE ORES

    Energy Technology Data Exchange (ETDEWEB)

    H. El-Shall; R. Stana; A. El-Midany; S. Malekzadah

    2004-12-17

    Presently the mining of Florida phosphate requires the movement of over a 100-ton of materials (overburden, sand, clay) for every ton of phosphate concentrate recovered. Not only is this energy intensive, but it also causes significant stress on the environment. In 2003, the Department of Energy solicited ideas for innovative mining ideas that could significantly improve the efficiency of mining. An award was made to the University of Florida Engineering Research Center to evaluate the in situ mining of phosphates using an aqueous CO{sub 2} solution. Tests were carried out in a 15.2 cm (6-inch) diameter column, 1.83 meter (6 feet) long at pressures up to 117.2 kg/cm{sup 2} (40 psi). Results to date demonstrate that initially the MgO is leached from the ore and then the phosphate. While the tests are continuing, so far they have not demonstrated P{sub 2}O{sub 5} concentrations that are economically attractive.

  8. Calibration of in-situ plasma instruments

    Science.gov (United States)

    Wüest, M.

    2003-12-01

    Calibration of scientific instruments is an important task. Only by proper calibration and understanding of the instrument can we address the scientific questions. Unfortunately, in the field of space plasma physics calibration is not considered science and therefore, calibration techniques and results are often not reported in the space physics literature. This paper reviews how in-situ particle instruments for plasma measurements are calibrated in the laboratory and in flight. Absolute calibration traceable to a national measurements institute is very difficult to achieve. A calibration transfer standard is suggested to reduce relative differences of individual calibration facilities with each other. Instrument degradation is of particular concern for long-term studies, but there is no inflight calibration standard either. Cross calibration with other instruments on the same spacecraft is described. In order to speed up the calibration for multi-spacecraft missions, several methods ranging from artificial intelligence methods, numerical ray tracing to improved vacuum chamber pump speed are suggested. In summary, there is a need for further improvements in the area of instrument calibrations, especially in light of the up-coming multi-spacecraft missions or for long-term studies of solar cycle effects.

  9. In situ recycling of contaminated soil uses bioremediation

    International Nuclear Information System (INIS)

    OxyChem Pipeline Operations, primarily an ethylene and propylene products mover, has determined that substantial savings can be realized by adopting a bioremediation maintenance and recycling approach to hydrocarbon-contaminated soil. By this method, the soil can be recycled in situ, or in containers. To implement the soil-recycling program, OxyChem elected to use a soil remediator and natural absorbent product, Oil Snapper. This field maintenance material, based on an Enhanced Urea Technology, provides a diet to stimulate the growth of hydrocarbon-eating microbes. It works well either with indigenous soil microbes or with commercial microbes. The product is carried in field vehicles, which makes it immediately available when leaks or spills are discovered. Procedure for clean-up is to apply product and mix it into affected soil. Thus the contaminant is contained, preventing further migration; the contaminant is dispersed throughout the product, making it more accessible to the microbes; nutrients are immediately available to the microbes; and the material contributes aeration and moisture-retention properties

  10. In situ treatment of VOCs by recirculation technologies

    International Nuclear Information System (INIS)

    The project described herein was conducted by Oak Ridge National Laboratory (ORNL) to identify processes and technologies developed in Germany that appeared to have near-term potential for enhancing the cleanup of volatile organic compound (VOC) contaminated soil and groundwater at DOE sites. Members of the ORNL research team identified and evaluated selected German technologies developed at or in association with the University of Karlsruhe (UoK) for in situ treatment of VOC contaminated soils and groundwater. Project activities included contacts with researchers within three departments of the UoK (i.e., Applied Geology, Hydromechanics, and Soil and Foundation Engineering) during fall 1991 and subsequent visits to UoK and private industry collaborators during February 1992. Subsequent analyses consisted of engineering computations, groundwater flow modeling, and treatment process modeling. As a result of these project efforts, two processes were identified as having near-term potential for DOE: (1) the vacuum vaporizer well/groundwater recirculation well and (2) the porous pipe/horizontal well. This document was prepared to summarize the methods and results of the assessment activities completed during the initial year of the project. The project is still ongoing, so not all facets of the effort are completely described in this document. Recommendations for laboratory and field experiments are provided

  11. In situ vadose zone remediation of petroleum-contaminated soils

    International Nuclear Information System (INIS)

    This paper discusses a pilot-scale system treating vadose zone soils contaminated with petroleum products constructed and operated at a former petroleum bulk storage terminal in New England. A site investigation following decommissioning activities identified more than 100,000 yds of soil at the site contaminated by both No. 2 fuel oil and gasoline. Soil cleanup criteria of 50 ppm TPH and 0.25 ppm BTEX were established. A pilot-scale treatment unit with dimensions of 125 ft x 125 ft x 6 ft was constructed to evaluate the potential for in situ treatment of vadose zone soils. Contaminant levels in pilot cell soils ranged from 0 to 5,250 ppm TPH and 0.0 to 4.2 ppm BTEX. Two soil treatment methods n the pilot system were implemented; venting to treat the lighter petroleum fractions and bioremediation to treat the nonvolatile petroleum constituents. Seven soil gas probes were installed to monitor pressure and soil gas vapor concentrations in the subsurface. Changes in soil gas oxygen and carbon dioxide concentrations were used as an indirect measure of enhanced bioremediation of pilot cell soils. After operating the system for a period of 2.5 months, soil BTEX concentrations were reduced to concentrations below the remediation criteria for the site

  12. Solvent screening methodology for in situ ABE extractive fermentation.

    Science.gov (United States)

    González-Peñas, H; Lu-Chau, T A; Moreira, M T; Lema, J M

    2014-07-01

    Solvent screening for in situ liquid extraction of products from acetone-butanol-ethanol (ABE) fermentation was carried out, taking into account biological parameters (biocompatibility, bioavailability, and product yield) and extraction performance (partition coefficient and selectivity) determined in real fermentation broth. On the basis of different solvent characteristics obtained from literature, 16 compounds from different chemical families were selected and experimentally evaluated for their extraction capabilities in a real ABE fermentation broth system. From these compounds, nine potential solvents were also tested for their biocompatibility towards Clostridium acetobutylicum. Moreover, bioavailability and differences in substrate consumption and total n-butanol production with respect to solvent-free fermentations were quantified for each biocompatible solvent. Product yield was enhanced in the presence of organic solvents having higher affinity for butanol and butyric acid. Applying this methodology, it was found that the Guerbet alcohol 2-butyl-1-octanol presented the best extracting characteristics (the highest partition coefficient (6.76) and the third highest selectivity (644)), the highest butanol yield (27.4 %), and maintained biocompatibility with C. acetobutylicum. PMID:24676748

  13. In situ synthesis of silver nano-particles in polymethylmethacrylate

    International Nuclear Information System (INIS)

    One-step in situ preparation of silver nano-particles in polymethylmethacrylate (PMMA) using N,N'-dimethylformamide (DMF) as a medium has been performed successfully. The radical polymerization of methaycrylic acid (MMA), in presence of benzoyl peroxide followed by reaction of silver source has been successfully employed to synthesize Ag/PMMA nano-composite. A light yellow solution in its UV-Vis absorption spectrum showed surface plasmon resonance absorption bands between 410 and 425 nm in solutions and at about 452 nm in a transparent film. The Ag/PMMA nano-composite was characterized by X-ray diffraction (XRD) measurement, transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform-infrared spectroscopy (FT-IR) and thermo-gravimetric analysis (TGA). XRD showed the fcc crystal structure of the bulk Ag with particles of less than 25 nm in size similar to that is observed by TEM. SEM indicated uniform distribution of particles in the film. TGA confirmed enhanced thermal stability of the polymer

  14. In situ synthesis of silver nano-particles in polymethylmethacrylate

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Narendra [Nanoscience Group, Centre for Materials for Electronics Technology (C-MET), Off Dr. Bhabha Road, Panchawati, Pune 411 008 (India); Khanna, P.K. [Nanoscience Group, Centre for Materials for Electronics Technology (C-MET), Off Dr. Bhabha Road, Panchawati, Pune 411 008 (India)], E-mail: pkkhanna@cmet.gov.in

    2007-08-15

    One-step in situ preparation of silver nano-particles in polymethylmethacrylate (PMMA) using N,N'-dimethylformamide (DMF) as a medium has been performed successfully. The radical polymerization of methaycrylic acid (MMA), in presence of benzoyl peroxide followed by reaction of silver source has been successfully employed to synthesize Ag/PMMA nano-composite. A light yellow solution in its UV-Vis absorption spectrum showed surface plasmon resonance absorption bands between 410 and 425 nm in solutions and at about 452 nm in a transparent film. The Ag/PMMA nano-composite was characterized by X-ray diffraction (XRD) measurement, transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform-infrared spectroscopy (FT-IR) and thermo-gravimetric analysis (TGA). XRD showed the fcc crystal structure of the bulk Ag with particles of less than 25 nm in size similar to that is observed by TEM. SEM indicated uniform distribution of particles in the film. TGA confirmed enhanced thermal stability of the polymer.

  15. Magnetospheric Interaction at Jupiter's Galilean Moons Io, Europa, Ganymede, Callisto: Galileo in-Situ Measurements Compared with Simulation Results

    Science.gov (United States)

    Krupp, N.; Jia, X.; Roussos, E.; Fraenz, M.

    2014-12-01

    Between 1995 and 2003 the Galileo spacecraft orbited Jupiter and flew-by multiple times at the Galilean satellites Io (7), Europa (12), Ganymede (5), and Callisto (8). The wealth of new unprecedented data from Galileo in-situ measurements in comparison to hybrid- and MHD simulation results enhanced our view of the understanding of the interaction between the moons (or in the case of Ganymede's own magnetosphere) and the surrounding highly dynamic Jovian magnetosphere. In this paper the in-situ particles and fields measurements are reviewed in the context of the future ESA-mission JUICE to arrive in the Jovian system in 2030.

  16. In Situ Peptide-MHC-II Tetramer Staining of Antigen-Specific CD4+ T Cells in Tissues

    OpenAIRE

    Dileepan, Thamotharampillai; Hyeon O Kim; Cleary, P. Patrick; Pamela J Skinner

    2015-01-01

    The invention of peptide-MHC-tetramer technology to label antigen-specific T cells has led to an enhanced understanding of T lymphocyte biology. Here we describe the development of an in situ pMHC-II tetramer staining method to visualize antigen-specific CD4+ T cells in tissues. This method complements other methods developed that similarly use MHC class II reagents to stain antigen-specific CD4+ T cells in situ. In this study, we used group A streptococcus (GAS) expressing a surrogate peptid...

  17. In situ X-ray investigations of oxygen precipitation in semiconductor silicon; In-situ-Roentgenuntersuchungen der Sauerstoffpraezipitation in Halbleitersilizium

    Energy Technology Data Exchange (ETDEWEB)

    Grillenberger, Hannes

    2011-03-04

    The precipitation of oxygen in Czochralski grown semiconductor silicon is investigated in situ during thermal treatments up to 1000 C with high energy X-rays. All investigations are performed with a focusing Laue diffractometer. The parameters of the diffraction curve are the relative full width at half maximum (rFHWM) and the enhancement of the integral intensity (EII). A readout software has been developed to extract these automatically from the detector image for the measured 220, -220 and 040 Bragg peaks. The sample thickness is set to 15 mm as this enhances the sensitivity of the method and the samples are processed after the strain-field diffraction (SFD) experiments to wafers for an ex situ characterization demanding wafers. Three experimental series with a total of 21 in situ SFD experiments with different thermal treatments have been performed. The slope of the initial temperature ramp is set to 1 K/min in the first and the third series to generate a high precipitate (Bulk Micro Defect, BMD) density. In the second series the slope is chosen as 10 K/min to generate a lower density in the same silicon material. It is shown with all experiments and with preliminary works that the built up of strain during the heat treatment is caused by BMDs during the high temperature period of the treatment. The detection limit of series 1 is found at 7 nm at a density of 10{sup 13}/cm{sup 3}, of series 2 at 40 nm at a density of 2 x 10{sup 8}/cm{sup 3}, and at 8 nm at a density of 4.8 x 10{sup 12}/cm{sup 3} for series 3. The local maximum of the EII at 450 C, which emerges coincident with a local minimum of the rFWHM in series 2 may be caused by thermal donors (TD). With the experiments is shown that SFD operates in the infrared-laser scattering tomography detection range, but also reaches in a region covered only by transmission electron microscopy (TEM) so far. In contrast to these methods SFD is not limited to low temperatures and in situ experiments can be done. Thus not only the ex situ verified BMD parameters but their temporal development can detected by SFD for the first time with a laboratory setup. An other difference to TEM is the number of BMDs detected. Measurements of the BMD parameters of a small number of BMDs can be done with TEM at a very high resolution to deduce the properties of the total BMD ensemble. The SFD signal is influenced directly by all BMDs in the analyzed sample volume being in the order of 10{sup 14}/cm{sup 3}. Correlations of the EII and BMD parameters are made for the first and the third series. A linear relation is found between the EII level and the BMD diameter if the BMD density is constant as in series 1. The influence of the BMD density on the EII signal is considerably in series 3. The final EII level is mainly depending on the density of the BMDs. The BMD diameters in the series may be assumed as constant in most of the samples, as the distribution of the diameters within one sample is wider than between the samples. A correlation of the BMD density measured with TEM with the maximum of the slope of the EII shows a strong linear relationship for first and third series. Values of the second series reduce the correlation coefficient, as the EII signal depends on the BMD diameter which is in a different order of magnitude in this series. (orig.)

  18. Combining Space-Based and In-Situ Measurements to Track Flooding in Thailand

    Science.gov (United States)

    Chien, Steve; Doubleday, Joshua; Mclaren, David; Tran, Daniel; Tanpipat, Veerachai; Chitradon, Royal; Boonya-aaroonnet, Surajate; Thanapakpawin, Porranee; Khunboa, Chatchai; Leelapatra, Watis; Plermkamon, Vichian; Raghavendra, Cauligi; Mandl, Daniel

    2011-01-01

    We describe efforts to integrate in-situ sensing, space-borne sensing, hydrological modeling, active control of sensing, and automatic data product generation to enhance monitoring and management of flooding. In our approach, broad coverage sensors and missions such as MODIS, TRMM, and weather satellite information and in-situ weather and river gauging information are all inputs to track flooding via river basin and sub-basin hydrological models. While these inputs can provide significant information as to the major flooding, targetable space measurements can provide better spatial resolution measurements of flooding extent. In order to leverage such assets we automatically task observations in response to automated analysis indications of major flooding. These new measurements are automatically processed and assimilated with the other flooding data. We describe our ongoing efforts to deploy this system to track major flooding events in Thailand.

  19. In situ luminescence qualification of radiation damage in aluminas: F-aggregation and Al colloids

    Energy Technology Data Exchange (ETDEWEB)

    Malo, M., E-mail: marta.malo@ciemat.es; Moroño, A.; Hodgson, E.R.

    2014-10-15

    Highlights: •Correlation between IBIL and surface electrical degradation. •Potential to remotely monitor degradation of insulating materials. •Possibility for in situ recovery of the insulating properties by thermal annealing. -- Abstract: Recent work for in situ sequential measurement of ion beam induced luminescence and surface electrical conductivity has identified a correlation between surface electrical degradation and the luminescence for aluminas and sapphire during 45 keV He ion bombardment. Detailed measurements for the initial stages of degradation where rapid changes in the luminescence emission bands occur, have now identified processes related to oxygen vacancy (F centre) aggregation and aluminium colloid production as precursors to measurable surface electrical degradation in the irradiated region. This understanding enhances the possibility of using ion beam induced luminescence as a potential monitoring tool for material evolution and insulator surface degradation during irradiation, not only in ITER and future fusion devices, but also in present experimental reactor materials test programmes.

  20. In situ luminescence qualification of radiation damage in aluminas: F-aggregation and Al colloids

    International Nuclear Information System (INIS)

    Highlights: •Correlation between IBIL and surface electrical degradation. •Potential to remotely monitor degradation of insulating materials. •Possibility for in situ recovery of the insulating properties by thermal annealing. -- Abstract: Recent work for in situ sequential measurement of ion beam induced luminescence and surface electrical conductivity has identified a correlation between surface electrical degradation and the luminescence for aluminas and sapphire during 45 keV He ion bombardment. Detailed measurements for the initial stages of degradation where rapid changes in the luminescence emission bands occur, have now identified processes related to oxygen vacancy (F centre) aggregation and aluminium colloid production as precursors to measurable surface electrical degradation in the irradiated region. This understanding enhances the possibility of using ion beam induced luminescence as a potential monitoring tool for material evolution and insulator surface degradation during irradiation, not only in ITER and future fusion devices, but also in present experimental reactor materials test programmes

  1. Doxorubicin-loaded zein in situ gel for interstitial chemotherapy of colorectal cancer

    Directory of Open Access Journals (Sweden)

    Ning Shen

    2012-12-01

    Full Text Available The aim of this research was to evaluate doxorubicin (DOX-loaded zein in situ gels, a new drug delivery system in which a liquid state drug can be transformed into semi-solid after intratumoral injection. In vitro release of DOX-loaded zein was investigated and the pharmacokinetics, biodistribution and therapeutic efficacy of these DOX-loaded zein formulations were investigated using BALB/c nude tumor-bearing mice. In vitro release of DOX from the gels extended up to 7 days. Efficient accumulation of DOX in the tumor with lower drug concentration in blood and normal organs was obtained resulting in effective inhibition of tumor growth and fewer off-target side effects. In conclusion, a DOX-loaded in situ gel was developed with sustained release, enhanced anti-cancer efficacy for colorectal cancer in vivo, and especially with reduced off-target side effects.

  2. In-situ microcosms, a tool for assessment of pesticide impacts on oyster spat (Crassostrea gigas).

    Science.gov (United States)

    Stachowski-Haberkorn, Sabine; Quiniou, Françoise; Nedelec, Morgane; Robert, René; Limon, Gwendolina; de la Broise, Denis

    2008-05-01

    Effects of the herbicide Basamaïs (bentazon) and the fungicide Opus (epoxiconazole) on oyster spat (Crassostrea gigas) were assessed using in-situ microcosms in a field experiment lasting 13 days. Six-week-old hatchery spat (mean size 1.1 mm), previously collected on PVC plates, was immersed in glass bottles filled with 200 mum filtered seawater. Bottles were maintained underwater at 6 m depth and their water content changed every other day. Growth, measured as shell area index increase, was 126 +/- 4% in the control bottles. While no growth differences were observed between control and individual pesticide treatments at 10 microg l(-1), oysters treated with a mix of 10 microg l(-1) Opus and 10 microg l(-1) Basamaïs showed a 50% growth reduction compared with the control (P < 0.0001), suggesting a synergistic effect of these contaminants. Laboratory controls in microcosms maintained in a water bath with filtered natural light, were not significantly different from in-situ microcosm controls in the field, for organic weight content or growth. This in-situ experiment in microcosms allowed us to conclude that: (1) oyster spat can achieve significant growth in bottles immersed in situ without supplementary food; (2) this microcosm system is reliable and easy to use for environmental toxicity tests with C. gigas spat; (3) such microcosm systems can also be run in a laboratory water bath instead of more technically difficult immersed field experiments; (4) the synergistic effect observed here, at a concentration simulating a peak agricultural runoff event, suggests that the impacts of pesticides could be a real threat for oysters in estuarine areas. PMID:18236155

  3. Laser in situ keratomileusis in adult patients with anisometropic amblyopia

    Directory of Open Access Journals (Sweden)

    Dilek Ya?a

    2013-06-01

    Full Text Available AIM: To evaluate the increase in corrected distance visual acuity (CDVA after laser in situ keratomileusis (LASIK in adults with anisometropic amblyopia.METHODS: The medical records of consecutive patients diagnosed with anisometropic amblyopia at the time of refractive evaluation who underwent LASIK were retrospectively reviewed. Patients with at least a two-line difference of visual acuity (VA between the eyes with a spherical refractive error difference of at least 3.00 diopters (D or an astigmatic difference of at least 2.00D were included. Patients with any other possible reason for amblyopia other than anisometropia or those who had undergone previous amblyopia treatment were excluded. Amblyopic eyes with myopia or myopic astigmatism were considered as group 1, hypermetropia or hypermetropic astigmatism constituted group 2, and mixed astigmatism patients comprised group 3. Uncorrected distance visual acuity (UDVA, subjective manifest refraction, and CDVA were analyzed at 1 week and 1 month, 3, and 6 months. RESULTS: The study included 57 eyes of 57 patients. There were 33 eyes in group 1, 12 eyes in group 2, and 12 eyes in group 3. The preoperative mean values for spherical equivalent of subjective manifest refraction (SE in groups 1, 2, and 3 were (-4.66±1.97D, (4.40±1.00D, and (0.15±1.05D, respectively. Mean CDVA improved 0.1 log units (1 line LogMAR at 6 months (P0.05. Moreover, age, the amount of preoperative refractive error, and the levels of preoperative corrected and UDVA had no effect on postoperative CDVA improvement (P>0.05.CONCLUSION: Correction of refractive errors with LASIK produced significant CDVA improvement in adult patients with anisometropic amblyopia and no previous amblyopia treatment.

  4. In situ bioremediation strategies for oiled shoreline environments

    International Nuclear Information System (INIS)

    Despite advances in preventative measures, recent events have demonstrated that accidental oil spills at sea will still occur. While physical (e.g. booms and skimmers) and chemical (e.g. chemical dispersants) methods have been developed to recover and/or disperse oil spilled at sea, they are not 100% effective and are frequently limited by operational constraints attributed to sea state and/or nature of the contamination. As a result, oil spills frequently impact shoreline environments. In situ bioremediation, the addition of substances or modification of habitat at contaminated sites to accelerate natural biodegradation processes, is now recognised as an alternative spill response technology of the remediation of these sites. Recommended for use following the physical removal of bulk oil, this treatment strategy has an operational advantage in that it breaks down and/or removes the residual contamination in place. Laboratory experiments and field trials have demonstrated the feasibility and success of bioremediation strategies such as nutrient enrichment to enhance bacterial degradation of oil on cobble, sand beach and salt marsh environments. With improved knowledge of the factors that limit natural oil degradation rates, the feasibility of other strategies such as phytoremediation, enhanced oil-mineral fines interaction and the addition of oxygen or alternative electron acceptors are now being evaluated. Laboratory and field test protocols are being refined for the selection of effective bioremediation agents and methods of application. It is recommended that future operational guidelines include real time product efficacy test and environmental effects monitoring programs. Termination of treatment should be implemented when: 1) it is no longer effective; 2) the oil has degraded to acceptable biologically benign concentrations; or 3) toxicity due to the treatment is increasing. (Author)

  5. Virtual Savannah : In Situ Test of a Virtual Learning 3D Visualization for children

    DEFF Research Database (Denmark)

    Rodil, Kasper; Eskildsen, SØren

    2012-01-01

    Virtual Savannah is constructed to visualize parts of a curriculum, which the educational service at Aalborg Zoo has difficulties in teaching children visiting the zoo. It contains rich media like audio, text, video and picture galleries about African ecology, but some of this episodic information has been visualized to a further extent in order to transfer it as semantic knowledge for the children to assimilate. Three in situ tests reflected through a set of assignments which prior knowledge the children had on the subject, if they could assimilate information from the system, and finally the children’s retention one week after the test, measuring if any learning had happened. The tests showed significant results by comparing prior knowledge with assimilated knowledge. It also showed significant results by comparing prior knowledge and knowledge retained one week after the test, which indicate that the children were not only able to use the system as intended, but they also learned from it.

  6. Environmental monitoring with in-situ gamma spectrometer; Umweltueberwachung mit in-situ-Gamma-Spektrometer

    Energy Technology Data Exchange (ETDEWEB)

    Reinhardt, S. [ENVINET GmbH, Haar (Germany)

    2014-01-20

    The in-situ gamma spectroscopy allows large area and continuous monitoring of the radio nuclides and there composition in the environment. In comparison to the gamma dose rate measurement the additional spectral information gives the possibility for a quick and effective action in the case of a man-made radiation exposition in the environment. The knowledge respectively localization of the possible nuclides, which a responsible for the increased dose rate, supports responsible organization in the quick identification of the situation, definition of the actions and tracking of the temporal and local process of the radiation exposition. Due to dedicate actions the risk for people and environment is reduced.

  7. In Situ Hydrocarbon Degradation by Indigenous Nearshore Bacterial Populations

    International Nuclear Information System (INIS)

    Potential episodic hydrocarbon inputs associated with oil mining and transportation together with chronic introduction of hydrocarbons via urban runoff into the relatively pristine coastal Florida waters poses a significant threat to Florida's fragile marine environment. It is therefore important to understand the extent to which indigenous bacterial populations are able to degrade hydrocarbon compounds and also determine factors that could potentially control and promote the rate at which these compounds are broken down in situ. Previous controlled laboratory experiments carried out by our research group demonstrated that separately both photo-oxidation and cometabolism stimulate bacterial hydrocarbon degradation by natural bacterial assemblages collected from a chronically petroleum contaminated site in Bayboro Bay, Florida. Additionally, we also demonstrated that stable carbon and radiocarbon abundances of respired CO2 could be used to trace in situ hydrocarbon degradation by indigenous bacterial populations at this same site. This current proposal had two main objectives: (a) to evaluate the cumulative impact of cometabolism and photo-oxidation on hydrocarbon degradation by natural bacterial assemblages collected the same site in Bayboro Bay, Florida and (b) to determine if in situ hydrocarbon degradation by indigenous bacterial populations this site could be traced using natural radiocarbon and stable carbon abundances of assimilated bacterial carbon. Funds were used for 2 years of full support for one ESI Ph.D. student, April Croxton. To address our first objective a series of closed system bacterial incubations were carried out using photo-oxidized petroleum and pinfish (i.e. cometabolite). Bacterial production of CO2 was used as the indicator of hydrocarbon degradation and (delta)13C analysis of the resultant CO2 was used to evaluate the source of the respired CO2 (i.e. petroleum hydrocarbons or the pinfish cometabolite). Results from these time series experiments demonstrated that short-term exposure of petroleum to UV light enhanced hydrocarbon degradation by 48% over that observed for non-photo-oxidized petroleum. Despite the greater bio-availability of the photo-oxidized over the non-photo-oxidized petroleum, an initial lag in CO2 production was observed indicating potential phototoxicity of the photo- by-products. (delta)13C analysis and mass balance calculations reveal that co-metabolism with pinfish resulted in increased hydrocarbon degradation for both photo-oxidized and non-photo-oxidized petroleum each by over 100%. These results demonstrate the cumulative effect of photo-oxidation and co-metabolism on petroleum hydrocarbon degradation by natural bacterial populations indigenous to systems chronically impacted by hydrocarbon input. To address the second objective of this proposal bacterial concentrates were collected from Bayboro Harbor in April 2001 for nucleic acid extraction and subsequent natural radiocarbon abundance analyses. Unfortunately, however, all of these samples were lost due to a faulty compressor in our -70 freezer. The freezer was subsequently repaired and samples were again collected from Bayboro Harbor in June 2002 and again December 2002. Several attempts were made to extract the nucleic acid samples--however, the student was not able to successfully extract and an adequate amount of uncontaminated nucleic acid samples for subsequent natural radiocarbon abundance measurements of the bacterial carbon by accelerator mass spectrometry (i.e. require at least 50 (micro)g carbon for AMS measurement). Consequently, we were not able to address the second objective of this proposed work

  8. MODIS comparisons with northeastern Pacific in situ stratocumulus microphysics

    Science.gov (United States)

    Noble, Stephen R.; Hudson, James G.

    2015-08-01

    Vertical sounding measurements within stratocumuli during two aircraft field campaigns, Marine Stratus/stratocumulus Experiment (MASE) and Physics of Stratocumulus Top (POST), are used to validate Moderate Resolution Imaging Spectroradiometer (MODIS) cloud optical thickness (COT), cloud liquid water path (LWP), and cloud effective radius (re). In situ COT, LWP, and re were calculated using 5 m vertically averaged droplet probe measurements of complete vertical cloud penetrations. MODIS COT, LWP, and re 1 km pixels were averaged along these penetrations. COT comparisons in POST showed strong correlations and a near 1:1 relationship. In MASE, comparisons showed strong correlations; however, MODIS COT exceeded in situ COT, likely due to larger temporal differences between MODIS and in situ measurements. LWP comparisons between two cloud probes show good agreement for POST but not MASE, giving confidence to POST data. Both projects provided strong LWP correlations but MODIS exceeded in situ by 14-36%. MODIS in situ re correlations were strong, but MODIS 2.1 µm re exceeded in situ re, which contributed to LWP bias; in POST, MODIS re was 20-30% greater than in situ re. Maximum in situ re near cloud top showed comparisons nearer 1:1. Other MODIS re bands (3.7 µm and 1.6 µm) showed similar comparisons. Temporal differences between MODIS and in situ measurements, airplane speed differences, and cloud probe artifacts were likely causes of weaker MASE correlations. POST COT comparison was best for temporal differences under 20 min. POST data validate MODIS COT but it also implies a positive MODIS re bias that propagates to LWP while still capturing variability.

  9. Cost performance assessment of in situ vitrification

    Energy Technology Data Exchange (ETDEWEB)

    Showalter, W.E.; Letellier, B.C.; Booth, S.R. [Los Alamos National Lab., NM (United States); Barnes-Smith, P. [ICF Kaiser Engineers, Inc., Albuquerque, NM (United States)

    1992-09-01

    In situ vitrification (ISV) is a thermal treatment technology with promise for the destruction or immobilization of hazardous materials in contaminated soils. It has developed over the past decade to a level of maturity where meaningful cost effectiveness studies may be performed. The ISV process melts 4 to 25 m{sup 2} of undisturbed soil to a maximum depth of 6 m into an obsidian-like glass waste form by applying electric current (3750 kill) between symmetrically spaced electrodes. Temperatures of approximately 2000{degree}C drive off and destroy complex organics which are captured in an off-gas treatment system, while radio-nuclides are incorporated into the homogeneous glass monolith. A comparative life-cycle cost evaluation between mobile rotary kiln incineration and ISV was performed to quantitatively identify appropriate performance regimes and components of cost which are sensitive to the implementation of each technology. Predictions of melt times and power consumption were obtained from an ISV performance model over ranges of several parameters including electrode spacing, soil moisture, melt depth, electrical resistivity, and soil density. These data were coupled with manpower requirements, capitalization costs, and a melt placement optimization routine to allow interpolation over a wide variety of site characteristics. For the purpose of this study, a single site scenario representative of a mixed waste evaporation pond was constructed. Preliminary comparisons between ISV and incineration show that while operating costs are comparable, ISV avoids secondary treatment and monitored storage of radioactive waste that would be required following conventional incineration. It is the long term storage of incinerated material that is the most expensive component.

  10. Cost performance assessment of in situ vitrification

    Energy Technology Data Exchange (ETDEWEB)

    Showalter, W.E.; Letellier, B.C.; Booth, S.R. (Los Alamos National Lab., NM (United States)); Barnes-Smith, P. (ICF Kaiser Engineers, Inc., Albuquerque, NM (United States))

    1992-01-01

    In situ vitrification (ISV) is a thermal treatment technology with promise for the destruction or immobilization of hazardous materials in contaminated soils. It has developed over the past decade to a level of maturity where meaningful cost effectiveness studies may be performed. The ISV process melts 4 to 25 m{sup 2} of undisturbed soil to a maximum depth of 6 m into an obsidian-like glass waste form by applying electric current (3750 kill) between symmetrically spaced electrodes. Temperatures of approximately 2000{degree}C drive off and destroy complex organics which are captured in an off-gas treatment system, while radio-nuclides are incorporated into the homogeneous glass monolith. A comparative life-cycle cost evaluation between mobile rotary kiln incineration and ISV was performed to quantitatively identify appropriate performance regimes and components of cost which are sensitive to the implementation of each technology. Predictions of melt times and power consumption were obtained from an ISV performance model over ranges of several parameters including electrode spacing, soil moisture, melt depth, electrical resistivity, and soil density. These data were coupled with manpower requirements, capitalization costs, and a melt placement optimization routine to allow interpolation over a wide variety of site characteristics. For the purpose of this study, a single site scenario representative of a mixed waste evaporation pond was constructed. Preliminary comparisons between ISV and incineration show that while operating costs are comparable, ISV avoids secondary treatment and monitored storage of radioactive waste that would be required following conventional incineration. It is the long term storage of incinerated material that is the most expensive component.

  11. In-Situ Wire Damage Detection System

    Science.gov (United States)

    Williams, Martha; Roberson, Luke; Tate, Lanetra; Smith, Trent; Gibson, Tracy; Medelius, Pedro; Jolley, Scott

    2012-01-01

    An In-Situ Wire Damage Detection System (ISWDDS) has been developed that is capable of detecting damage to a wire insulation, or a wire conductor, or to both. The system will allow for realtime, continuous monitoring of wiring health/integrity and reduce the number of false negatives and false positives while being smaller, lighter in weight, and more robust than current systems. The technology allows for improved safety and significant reduction in maintenance hours for aircraft, space vehicles, satellites, and other critical high-performance wiring systems for industries such as energy production and mining. The integrated ISWDDS is comprised of two main components: (1) a wire with an innermost core conductor, an inner insulation film, a conductive layer or inherently conductive polymer (ICP) covering the inner insulation film, an outermost insulation jacket; and (2) smart connectors and electronics capable of producing and detecting electronic signals, and a central processing unit (CPU) for data collection and analysis. The wire is constructed by applying the inner insulation films to the conductor, followed by the outer insulation jacket. The conductive layer or ICP is on the outer surface of the inner insulation film. One or more wires are connected to the CPU using the smart connectors, and up to 64 wires can be monitored in real-time. The ISWDDS uses time domain reflectometry for damage detection. A fast-risetime pulse is injected into either the core conductor or conductive layer and referenced against the other conductor, producing transmission line behavior. If either conductor is damaged, then the signal is reflected. By knowing the speed of propagation of the pulse, and the time it takes to reflect, one can calculate the distance to and location of the damage.

  12. Ductal carcinoma in situ: a challenging disease

    Directory of Open Access Journals (Sweden)

    Sevilay Altintas

    2011-12-01

    Full Text Available Ductal carcinoma in situ (DCIS represents a heterogenous group of lesions with variable malignant potential. Although it is clearly pre-invasive, not all lesions progress to an invasive malignant disease. The significant increase in the frequency of diagnosis is the result of both widespread use of screening mammography and better recognition among pathologists. Treatment is controversial, but for several decades total mastectomy has been considered as the appropriate treatment. The tendency to be less aggressive in terms of surgery has followed the pattern of events observed in the treatment of invasive breast carcinomas. More recently, it has become clear that breastconserving procedures could be applied and selected on the basis of diagnostics and risk factors. When all patients with DCIS are considered, the overall mortality is extremely low, only about 1–2%. On the other hand, breast-conserving surgery is only curative in 75–85%; 50% of the local recurrences have proven to be invasive with a mortality rate of 12–15%. There is no place for axillary node dissection, adjuvant hormonal treatment or chemotherapy in the treatment. Important factors in predicting local recurrence are age, family history, nuclear grade, comedo-type necrosis, tumor size and margin width. With the addition of radiation therapy to excisional surgery, there is a 50% reduction in the overall local recurrence rate. The Van Nuys Prognostic Index (VNPI, recently updated, is a tool that quantifies measurable prognostic factors that can be used in the decision-making process of treatment. Recent data from large cohort studies and randomized trials have emerged to guide treatment. DCIS is now understood to have diverse malignant potential and it is unlikely that there will be a single treatment for this wide range of lesions. Advances in molecular biology and gene expression profiling of human breast tumors have been providing important insights into the relationship between DCIS and invasive breast cancer.

  13. NOVEL IN-SITU METAL AND MINERAL EXTRACTION TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Glenn O' Gorman; Hans von Michaelis; Gregory J. Olson

    2004-09-22

    This white paper summarizes the state of art of in-situ leaching of metals and minerals, and describes a new technology concept employing improved fragmentation of ores underground in order to prepare the ore for more efficient in-situ leaching, combined with technology to continuously improve solution flow patterns through the ore during the leaching process. The process parameters and economic benefits of combining the new concept with chemical and biological leaching are described. A summary is provided of the next steps required to demonstrate the technology with the goal of enabling more widespread use of in-situ leaching.

  14. Effect of in situ acids removal on mixed glucose and xylose fermentation by Clostridium tyrobutyricum.

    Science.gov (United States)

    Baroi, George Nabin; Skiadas, Ioannis V; Westermann, Peter; Gavala, Hariklia N

    2015-12-01

    In the present study, the effect of potassium ions and increasing concentrations of glucose and xylose on the growth of a strain of Clostridium tyrobutyricum, adapted to wheat straw hydrolysate, was investigated. Application of continuous fermentation of a mixture of glucose and xylose and in situ acid removal by reverse electro enhanced dialysis (REED) was investigated as a method to alleviate potassium and end-product inhibition and consequently enhance the sugar consumption rates and butyric acid productivity. It was found that glucose and xylose were not inhibitory up to a concentration of 50 and 37 g L(-1) respectively, and that they were consumed at comparable rates when fermented alone. However, continuous fermentation of a mixture of glucose and xylose resulted in a significantly decreased xylose consumption rate compared to that of glucose alone, supporting the conclusion that C. tyrobutyricum has a lower affinity for xylose than for glucose. Potassium ions negatively affected the effective maximum growth rate of C. tyrobutyricum at concentrations higher than 5 g L(-1) exhibiting a non-competitive type of inhibition. Continuous fermentation of a glucose and xylose mixture with simultaneous acid removal by REED resulted in a two to threefold increase of the glucose consumption rate, while the xylose consumption rate was enhanced sixfold compared to continuous fermentation without in situ acid removal. Similarly, butyric acid productivity was enhanced by a factor of 2-3, while the yield remained unaffected. PMID:26516087

  15. Epoxidação "in situ" aplicada ao látex de borracha natural / "In situ" epoxidation of natural rubber latex

    Scientific Electronic Library Online (English)

    Cristiane K., Santin; Gisele de C., Pinto; Marly Maldaner, Jacobi.

    Full Text Available O comportamento da borracha natural na forma látex frente à reação de epoxidação foi avaliado visando estabelecer as melhores condições reacionais sem a ocorrência de reações laterais, que promovem a coagulação do látex e o desenvolvimento de um aglomerado de borracha. Grupos epóxidos foram gerados [...] através da reação de epoxidação a partir da formação in situ do ácido perfórmico. As amostras foram caracterizadas qualitativamente por espectroscopia de infravermelho (FTIR) e o grau de modificação determinado por ressonância magnética nuclear de hidrogênio (1H-RMN). Análises de calorimetria exploratória diferencial (DSC) demonstraram que a mobilidade da cadeia polimérica foi influenciada pela presença de grupos epóxidos, com aumento linear na temperatura de transição vítrea (Tg). Os resultados indicaram que a epoxidação do látex de borracha natural, sem a ocorrência de reações laterais, é possível e dependente das condições reacionais. Abstract in english Natural rubber latex was submitted to epoxidation reaction to establish the best reaction conditions without the occurrence of side reactions, which promote coagulation of the latex and development of an agglomerate of rubber. Epoxy groups were produced by in situ epoxidation with formic acid and hy [...] drogen peroxide. The samples were characterized qualitatively by Fourier Transform Infrared (FTIR) analysis and the degree of modification determined by Hydrogen Nuclear Magnetic Resonance Spectroscopy (1H-NMR) analysis. A linear increase in the glass transition temperature (Tg) was observed. The results show that the epoxidation of natural rubber latex is possible and depends on the reaction conditions.

  16. In situ bioremediation via horizontal wells

    International Nuclear Information System (INIS)

    The test consisted of methane mixed with air into the contaminated aquifer via a horizontal well and extraction from the vadose zone via a parallel horizontal well. This configuration has the advantage of simultaneously stimulating methanotrophic activity in both the groundwater and vadose zone, and inhibiting spread of the contaminant plume. Groundwater was monitored biweekly from 13 wells for a variety of chemical and microbiological parameters. Groundwater from wells in affected areas showed increases in methanotrophs of more than 1 order of magnitude every 2 weeks for several weeks after 1% methane-in-air injection was started. Some wells had increases as much as 7 orders of magnitude. Simultaneous with the increase in methanotrophs was a decrease in water and soil gas concentrations of trichloroethylene (TCE) and tetrachloroethane (PCE). Two wells declined in TCE/PCE concentration in the water by more than 90% to below 2 ppb. All of the wells in the affected zone showed significant decreases in contaminants in less than one month. Chloride concentrations in the water were inversely correlated with TCE/PCE concentration. Four of five vadose zone piezometers declined from concentration as high as 10,000 ppm to less than 5 ppm in less than 6 weeks. The fifth cluster also declined by more than 95%. After only three months on injection, a decline in TCE/PCE in the sediment of more than 30% was also observed, with TCE/PCE being undetectable in most sediments at the end of the 14-month test. Gene probes and direct isolation from the water and sediment revealed that the right types of methanotrophs were being stimulated and that isolates could degrade TCE at a high rate

  17. Novel Instrumentation for In Situ Combustion Measurements Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the Phase I is to develop, demonstrate and test a novel instrument based on laser absorption diagnostics for fast, in situ measurements of...

  18. In Situ Oxygen Production from Lunar and Martian Regolith Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In situ oxygen production is of immense importance to NASA in the support of the NASA initiative to sustain man's permanent presence in space. The oxygen produced...

  19. In-situ Airborne Sampler for Advanced Guided Dropsonde Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed innovation is a low-cost, retrievable and reusable, autonomously guided dropsonde capable of in-situ atmospheric measurements. The proposed effort will...

  20. In situ sampling cart development engineering task plan

    International Nuclear Information System (INIS)

    This Engineering Task Plan (ETP) supports the development for facility use of the next generation in situ sampling system for characterization of tank vapors. In situ sampling refers to placing sample collection devices (primarily sorbent tubes) directly into the tank headspace, then drawing tank gases through the collection devices to obtain samples. The current in situ sampling system is functional but was not designed to provide the accurate flow measurement required by today's data quality objectives (DQOs) for vapor characterization. The new system will incorporate modern instrumentation to achieve much tighter control. The next generation system will be referred to in this ETP as the New In Situ System (NISS) or New System. The report describes the current sampling system and the modifications that are required for more accuracy

  1. Pushing the envelope of in situ transmission electron microscopy.

    Science.gov (United States)

    Ramachandramoorthy, Rajaprakash; Bernal, Rodrigo; Espinosa, Horacio D

    2015-05-26

    Recent major improvements to the transmission electron microscope (TEM) including aberration-corrected electron optics, light-element-sensitive analytical instrumentation, sample environmental control, and high-speed and sensitive direct electron detectors are becoming more widely available. When these advances are combined with in situ TEM tools, such as multimodal testing based on microelectromechanical systems, key measurements and insights on nanoscale material phenomena become possible. In particular, these advances enable metrology that allows for unprecedented correlation to quantum mechanics and the predictions of atomistic models. In this Perspective, we provide a summary of recent in situ TEM research that has leveraged these new TEM capabilities as well as an outlook of the opportunities that exist in the different areas of in situ TEM experimentation. Although these advances have improved the spatial and temporal resolution of TEM, a critical analysis of the various in situ TEM fields reveals that further progress is needed to achieve the full potential of the technology. PMID:25942405

  2. In situ bioremediation of chlorinated solvent with natural gas

    International Nuclear Information System (INIS)

    A bioremediation system for the removal of chlorinated solvents from ground water and sediments is described. The system involves the the in-situ injection of natural gas (as a microbial nutrient) through an innovative configuration of horizontal wells

  3. Advanced hydraulic fracturing methods to create in situ reactive barriers

    International Nuclear Information System (INIS)

    This article describes the use of hydraulic fracturing to increase permeability in geologic formations where in-situ remedial action of contaminant plumes will be performed. Several in-situ treatment strategies are discussed including the use of hydraulic fracturing to create in situ redox zones for treatment of organics and inorganics. Hydraulic fracturing methods offer a mechanism for the in-situ treatment of gently dipping layers of reactive compounds. Specialized methods using real-time monitoring and a high-energy jet during fracturing allow the form of the fracture to be influenced, such as creation of assymmetric fractures beneath potential sources (i.e. tanks, pits, buildings) that should not be penetrated by boring. Some examples of field applications of this technique such as creating fractures filled with zero-valent iron to reductively dechlorinate halogenated hydrocarbons, and the use of granular activated carbon to adsorb compounds are discussed

  4. CLASIC07 In Situ Vegetation Data V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set includes in situ vegetation data collected during the Cloud and Land Surface Interaction Campaign 2007 (CLASIC07) campaign. Sampling was designed to...

  5. In situ transesterification of highly wet microalgae using hydrochloric acid.

    Science.gov (United States)

    Kim, Bora; Im, Hanjin; Lee, Jae W

    2015-06-01

    This study addresses in situ transesterification of highly wet microalgae with hydrochloric acid (HCl) as a catalyst. In situ transesterification was performed by heating the mixture of wet algal cells, HCl, methanol, and solvent in one pot, resulting in the fatty acid methyl ester (FAME) yield over 90% at 95°C. The effects of reaction variables of temperature, amounts of catalyst, reactant, and solvent, and type of solvents on the yield were investigated. Compared with the catalytic effect of H2SO4, in situ transesterification using HCl has benefits of being less affected by moisture levels that are as high as or above 80%, and requiring less amounts of catalyst and solvent. For an equimolar amount of catalyst, HCl showed 15wt.% higher FAME yield than H2SO4. This in situ transesterification using HCl as a catalyst would help to realize a feasible way to produce biodiesel from wet microalgae. PMID:25769690

  6. Rapid Optical Characterization Suite for in situ Target Analysis of Rock Surfaces Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ROCSTAR is an in situ instrument suite that can accomplish rapid mineral and molecular identification without sample preparation for in situ planetary exploration;...

  7. In Situ Probe Science at Saturn

    Science.gov (United States)

    Atkinson, D.H.; Lunine, J.I.; Simon-Miller, A. A.; Atreya, S. K.; Brinckerhoff, W.; Colaprete, A.; Coustenis, A.; Fletcher, L. N.; Guillot, T.; Lebreton, J.-P.; Mahaffy, P.; Mousis, O.; Orton, G. S.; Reh, K.; Spilker, L. J.; Spilker, T. R.; Webster, C.

    2014-01-01

    A fundamental goal of solar system exploration is to understand the origin of the solar sys-tem, the initial stages, conditions, and processes by which the solar system formed, how the formation pro-cess was initiated, and the nature of the interstellar seed material from which the solar system was born. Key to understanding solar system formation and subsequent dynamical and chemical evolution is the origin and evolution of the giant planets and their atmospheres. Several theories have been put forward to explain the process of solar system formation, and the origin and evolution of the giant planets and their atmospheres. Each theory offers quantifiable predictions of the abundances of noble gases He, Ne, Ar, Kr, and Xe, and abundances of key isotopic ratios 4He3He, DH, 15N14N, 18O16O, and 13C12C. Detection of certain dis-equilibrium species, diagnostic of deeper internal pro-cesses and dynamics of the atmosphere, would also help discriminate between competing theories. Measurements of the critical abundance profiles of these key constituents into the deeper well-mixed at-mosphere must be complemented by measurements of the profiles of atmospheric structure and dynamics at high vertical resolution and also require in situ explora-tion. The atmospheres of the giant planets can also serve as laboratories to better understand the atmospheric chem-istries, dynamics, processes, and climates on all planets including Earth, and offer a context and provide a ground truth for exoplanets and exoplanetary systems. Additionally, Giant planets have long been thought to play a critical role in the development of potentially habitable planetary systems. In the context of giant planet science provided by the Galileo, Juno, and Cassini missions to Jupiter and Sat-urn, a small, relatively shallow Saturn probe capable of measuring abundances and isotopic ratios of key at-mospheric constituents, and atmospheric structure in-cluding pressures, temperatures, dynamics, and cloud locations and properties not accessible by remote sens-ing can serve to test competing theories of solar system and giant planet origin, chemical, and dynamical evolution.

  8. LIBS for Tokamak in situ tritium inventory

    International Nuclear Information System (INIS)

    Full text of publication follows: During Tokamak operation and due to high energy and particle fluxes interacting with Plasma Facing Components (PFCs), wall materials are eroded, transported and redeposited in layers able to trap tritium. The accumulation of tritium in the vacuum vessel is limited due to safety constraint and the evaluation of the in vessel tritium inventory is of crucial interest. The spectroscopic analysis of the plasma produced by laser ablation of the PFCs and/or of the redeposited material, known as laser-induced breakdown spectroscopy (LIBS), is a promising technique to achieve this goal. Laser methods for surface characterisation and cleaning are under intensive studies in CEA within the frames of the ITER project and EFDA programs 1-5. In the following paper, a parametric study performed to determine the optimised operational conditions for LIBS analyses with tokamak samples will be first described. The influence on the plasma properties of the irradiation conditions (laser wavelength and pulse duration) and of the gas pressure and nature are investigated. Using several experimental techniques, it will be shown that long pulse duration (>10 ns) induced a too small plasma temperature for Tritium quantitative measurements. Usually, quantitative LIBS analyses require calibration measurements using standard samples having compositions close to that of the material to be analyzed. Calibration during tokamak operation is always difficult due to the complex material supposed to be produced. For ITER application, it is proposed here to apply a calibration-free LIBS procedure based on the calculation of the spectral radiance of the plasma in Local Thermodynamic Equilibrium. These new procedure will be exemplified on the determination of the deuterium concentration on real Tokamak samples coming from the Tore Supra tokamak. Then, the first experimental results obtained in Tokamak are recalled. It is observed that the complexity of the Tokamak environment leads to a complicated diagnostic especially if all the surface of the in vessel components must be analysed. The extrapolation of the LIBS diagnostic to ITER is then addressed with a special insight on embarked diagnostic able to scan the entire vessel walls. References: 1) 'Evaluation of Laser Ablation Optical Emission Spectroscopy Method for Graphite co-deposited Layer Characterisation', CEA report NT DPC/SCP/05-124-A, February 2005, 77 pp.; 2) 'Fusion Engineering and Design' 81 (2006) 1503-1509; 3) 'Fusion Science and Technology', 54 (2008) 51-54; 4) 'In situ Laser Breakdown Spectroscopy of JET Deposited Layers', CEA report NT DPC/SCP 08-293, Dec. 2008, 72 pp.; 5) 'Laser-Induced Breakdown Spectroscopy for deposited layer characterisation', CEA report NT DPC / SCP 09-309, May 2009, 83 pp. (authors)

  9. A in Situ Investigation of Silicon

    Science.gov (United States)

    Sharp, Jeffrey Wade

    An investigation of the surface kinetic processes of low pressure chemical vapor deposition (LPCVD) of Si, Ge, and rm Si_{x}Ge_ {1-x} was carried out using time-resolved differential reflectance measurements. The source gas (disilane, digermane, or mixtures of these two, diluted in a helium carrier) was delivered to a heated substrate by a fast-acting modulated molecular jet valve. Thin film growth was studied in the temperature range of 400-500 ^circC on Si and Ge (001) substrates. The kinetics of chemisorption and of by-product desorption were determined from the surface differential reflectance signal obtained using a p-polarized, high-stability HeNe probe laser. Both chemisorption and by-product desorption were fond to obey first-order kinetics. Chemisorption of the parent molecules was found to be relatively efficient (~5%) and weakly temperature dependent. For pure Si and Ge, by-product desorption occurred through a single first-order reaction. The activation energy of this step, ~2.75 eV for Si and ~1.5-2.2 eV for Ge, suggests that for both surfaces the stable chemisorption by-product is the monohydride, which decomposes via the elimination of molecular hydrogen. Two first-order desorption steps were inferred for the rm Si_{x}Ge _{1-x} alloy surfaces. These reaction are believed to he H_2 desorption from Si-like and Ge-like surface sites. However, the activation energy of the more rapid of these two steps actually decreases as the Si content of the film increases. Generally, the films were of high crystalline quality and were very well aligned with the substrate. Preferential incorporation of digermane into the film produced an alloy composition that was Ge-rich relative to the gas composition. The primary accomplishment of this work is the demonstration that the active surface layer of the important rm Si_{x}Ge_{1 -x} system can be monitored in situ by an optical probe under typical LPCVD conditions. The results that we have obtained to date indicate that the rate-limiting step in Si or Ge LPCVD obeys simple first-order kinetics. Two first-order desorption steps were inferred for rm Si_{x}Ge_{1-x} alloy surfaces, but further work is needed to understand fully the rate-limiting surface reaction in rm Si_{x}Ge_{1-x} LPCVD.

  10. A sediment ecotoxicity assessment platform for in situ measures of chemistry, bioaccumulation and toxicity. Part 1: System description and proof of concept

    International Nuclear Information System (INIS)

    In situ-based testing using aquatic organisms has been widely reported, but is often limited in scope and practical usefulness in making decisions on ecological risk and remediation. To provide this capability, an integrated deployment system, the Sediment Ecotoxicity Assessment (SEA) Ring was developed, which incorporates rapid in situ hydrological, chemical, bioaccumulation, and toxicological Lines-of-Evidence (LoE) for assessing sediment and overlying water contamination. The SEA Ring system allows for diver-assisted, or diverless, deployment of multiple species of ecologically relevant and indigenous organisms in three different exposures (overlying water, sediment–water interface, and bulk sediment) for periods ranging from two days to three weeks, in a range of water systems. Measured endpoints were both sublethal and lethal effects as well as bioaccumulation. In addition, integrated passive sampling devices for detecting nonpolar organics (solid phase micro-extraction fibers) and metals (diffusive gradients in thin films) provided gradient measures in overlying waters and surficial sediments. - Highlights: ? In situ bioassays help improve linkages between exposure and effects. ? SEA Ring is an in situ assessment tool for characterizing sediment quality. ? In situ bioassays and physicochemical assessment tools can link exposure and effects. ? Groundwater seepage presented limited risk at estuarine sediment site. - An in situ platform was created for evaluating the exposure and effects to multiple aquatic species.

  11. Characterization of VPO ammoxidation catalysts by in situ methods

    Energy Technology Data Exchange (ETDEWEB)

    Martin, A.; Luecke, B.; Brueckner, A.; Steinike, U. [Institut fuer Angewandte Chemie Berlin-Adlershof e.V., Berlin (Germany); Brzezinka, K.W. [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany); Meisel, M. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Chemie

    1998-12-31

    In-situ methods are well known as powerful tools in studying catalyst formation processes, their solid state properties under working conditions and the interaction with the feed, intermediates and products to reveal reaction mechanisms. This paper gives a short overview on results of intense studies using in-situ techniques to reveal VPO catalyst generation processes, interaction of educts, intermediates and products with VPO catalyst surfaces and mechanistic insights. Catalytic data of the ammoxidation of toluene on different VPOs complete these findings. The precursor-catalyst transformation processes were preferently investigated by in-situ XRD, in-situ Raman and in-situ ESR spectroscopy. The interaction of aromatic molecules and intermediates, resp., and VPO solid surfaces was followed by in-situ ESR and in-situ FTIR spectroscopy. Mechanistic information was mainly obtained using in-situ FTIR spectroscopy and the temporal-analysis-of-products (TAP) technique. Catalytic studies were carried out in a fixed-bed microreactor on pure (NH{sub 4}){sub 2}(VO){sub 3}(P{sub 2}O{sub 7}){sub 2}, generated [(NH{sub 4}){sub 2}(VO{sub 3})(P{sub 2}O{sub 7}){sub 2}+V{sub x}O{sub y}] catalysts, having different V{sub x}O{sub y} proportions by use of VOHPO{sub 4} x 1/2H{sub 2}O (V/P=1) and recently studied (VO){sub 3}(PO{sub 4}){sub 2} x 7 H{sub 2}O (V/P=1.5) precursors; the well-known (VO){sub 2}P{sub 2}O{sub 7} was used for comparison. (orig.)

  12. Polypropylene/graphite nanocomposites by in situ polymerization

    International Nuclear Information System (INIS)

    This work presents the synthesis of nanocomposites of polypropylene/graphite by in situ polymerization using metallocene catalyst and graphene nanosheets. Initially was analyzed which of the metallocene catalysts rac-Et(Ind)2ZrCl2 or rac-Me2Si(Ind)2ZrCl2 produces polypropylene with mechanical properties more relevant. Then it were performed the in situ polymerization reactions to obtain the nanocomposites. The polymeric materials were characterized by XRD, DSC, GPC and DMTA. (author)

  13. Challenges in subsurface in situ remediation of chlorinated solvents

    DEFF Research Database (Denmark)

    Broholm, Mette Martina; Fjordbøge, Annika Sidelmann; Christiansen, Camilla Maymann; Hønning, J.; Hansen, B. H.; Nedergaard, L. W.; Kern, Kristina; Uthuppu, Basil; Jakobsen, Mogens Havsteen; Kjeldsen, Peter; Bjerg, Poul Løgstrup; Ottesen, L.

    2014-01-01

    Chlorinated solvent source zones in the subsurface pose a continuous threat to groundwater quality at many sites worldwide. In situ remediation of these sites is particularly challenging in heterogeneous fractured media and where the solvents are present as DNAPL. In situ remediation by chemical as well as biological degradation of chlorinated solvents is a contact sport and requires direct contact between the contaminant and the reactants and/or degrading microorganisms. In fractured geologic m...

  14. Superconducting proximity effect for in situ and model layered systems

    International Nuclear Information System (INIS)

    The primary drawback for in situ composites is that the ac losses are higher than for mechanically produced multifilamentary wire. To develop an understanding of the proximity effect so that analytical expressions will be available for design, a model system is developed based on PbCd. Items discussed include boundary conditions at SN interface, phonon spectral function, supercurrents through normal barriers, flux entry fields, and implications for in situ composites

  15. SOXHLET EXTRACTION OF PENTACHLOROPHENOL FROM SOIL WITH IN SITU DERIVATIZATION

    OpenAIRE

    S. M SOTO-CORDOBA; Baeza, J.; Freer, J.

    2001-01-01

    The traditional Soxhlet extraction of pentachlorophenol (PCP) from soil samples has been modified to allow a rapid and efficient extraction. The modified procedure includes a derivatization in situ of the soil sample during the extraction. The traditional Soxhlet extraction (TSE) was compared with Soxhlet extraction with in situ derivatization (SED). Two different mixtures of derivative reactives, trietylamine-acetic anhydride (TEA-AA) and pyridine-acetic anhydride (PYR-AA), were utilized. Un...

  16. Nanoparticles laden in situ gel for sustained ocular drug delivery

    OpenAIRE

    Gupta, Himanshu; Aqil, Mohammed; Khar, Roop K.; Ali, Asgar; Bhatnagar, Aseem; Mittal, Gaurav

    2013-01-01

    Proper availability of drug on to corneal surface is a challenging task. However, due to ocular physiological barriers, conventional eye drops display poor ocular bioavailability of drugs (< 1%). To improve precorneal residence time and ocular penetration, earlier our group developed and evaluated in situ gel and nanoparticles for ocular delivery. In interest to evaluate the combined effect of in situ gel and nanoparticles on ocular retention, we combined them. We are the first to term this c...

  17. Improving accuracy of in situ gamma-ray spectrometry

    OpenAIRE

    Boson, Jonas

    2008-01-01

    Gamma-ray spectrometry measurements performed on site, or “in situ”, is a widely used and powerful method that can be employed both to identify and quantify ground deposited radionuclides. The purpose of this thesis is to improve the calibration of high purity germanium (HPGe) detectors for in situ measurements, and calculate the combined uncertainty and potential systematic effects. An improved semi-empirical calibration method is presented, based on a novel expression for the intrinsic dete...

  18. Telomere analysis by fluorescence in situ hybridization and flow cytometry.

    OpenAIRE

    Hultdin, M; Grönlund, E; Norrback, K; Eriksson-Lindström, E; Just, T; Roos, G.

    1998-01-01

    Determination of telomere length is traditionally performed by Southern blotting and densitometry, giving a mean telomere restriction fragment (TRF) value for the total cell population studied. Fluorescence in situ hybridization (FISH) of telomere repeats has been used to calculate telomere length, a method called quantitative (Q)-FISH. We here present a quantitative flow cytometric approach, Q-FISHFCM, for evaluation of telomere length distribution in individual cells based on in situ hybrid...

  19. In?situ permeability from integrated poroelastic reflection coefficients :

    OpenAIRE

    Dalen, K.N. van; Ghose, R.; Drijkoningen, C.G.; Smeulders, D.M.J.

    2010-01-01

    A reliable estimate of the in?situ permeability of a porous layer in the subsurface is extremely difficult to obtain. We have observed that at the field seismic frequency band the poroelastic behavior for different seismic wavetypes can differ in such a way that their combination gives unique estimates of in?situ permeability and porosity simultaneously. This is utilized in the integration of angle? and frequency?dependent poroelastic reflection coefficients in a cost function. Realistic nume...

  20. Advanced and In Situ Analytical Methods for Solar Fuel Materials.

    Science.gov (United States)

    Chan, Candace K; Tüysüz, Harun; Braun, Artur; Ranjan, Chinmoy; La Mantia, Fabio; Miller, Benjamin K; Zhang, Liuxian; Crozier, Peter A; Haber, Joel A; Gregoire, John M; Park, Hyun S; Batchellor, Adam S; Trotochaud, Lena; Boettcher, Shannon W

    2016-01-01

    In situ and operando techniques can play important roles in the development of better performing photoelectrodes, photocatalysts, and electrocatalysts by helping to elucidate crucial intermediates and mechanistic steps. The development of high throughput screening methods has also accelerated the evaluation of relevant photoelectrochemical and electrochemical properties for new solar fuel materials. In this chapter, several in situ and high throughput characterization tools are discussed in detail along with their impact on our understanding of solar fuel materials. PMID:26267386

  1. Matrix diffusion model. In situ tests using natural analogues

    International Nuclear Information System (INIS)

    Matrix diffusion is an important retarding and dispersing mechanism for substances carried by groundwater in fractured bedrock. Natural analogues provide, unlike laboratory or field experiments, a possibility to test the model of matrix diffusion in situ over long periods of time. This thesis documents quantitative model tests against in situ observations, done to support modelling of matrix diffusion in performance assessments of nuclear waste repositories

  2. In situ hybridization detection of microRNAs

    OpenAIRE

    SONG, RUI; Ro, Seungil; Yan, Wei

    2010-01-01

    microRNAs (miRNAs) are endogenous ~22 nucleotide RNAs that play critical roles in many cellular processes including cell differentiation, proliferation and apoptosis. The analysis of spatiotemporal expression of miRNAs is important for dissecting their roles in development and during physiological/pathophysiological processes. In situ hybridization is a powerful technology that allows cellular localization. miRNA in situ hybridization, however, has been challenging because of the low affinity...

  3. Next-generation in-situ science concepts and technology

    Science.gov (United States)

    Muirhead, Brian; Varsi, Giulio

    1990-01-01

    This paper discusses the concepts of a next-generation in situ science program, named Sample Acquisition, Analysis, and Preservation (SAAP), established by NASA to develop critical technologies for remote identification, acquisition, processing, analysis, and preservation of materials for the in situ science, engineering characterization, and earth return. Special attention is given to the SAAP architecture, system design, remote sensing system, sample acquisition system, and methods for sample analysis. A diagram of the SAAP preliminary system conceptual design is included.

  4. Oxygen-free in situ scanning tunnelling microscopy

    DEFF Research Database (Denmark)

    Zhang, Jingdong; Ulstrup, Jens

    2007-01-01

    Scanning tunneling microscopy under full electrochemical potential control (in situ STM) has been used extensively as an efficient method to characterize microstructures at solid/liquid interfaces at the atomic and molecular levels. However, under ambient conditions oxygen may interfere in open in situ STM systems by diffusion through the solutions. Such interference can be serious for oxygen sensitive systems both for the target molecules themselves and for chemical linker molecules bound to th...

  5. In situ measurements of Li isotopes in foraminifera

    OpenAIRE

    Vigier, Nathalie; Rollion-bard, Claire; Spezzaferri, Silvia; Brunet, Fabrice

    2007-01-01

    In situ measurement of Li isotope ratios in foraminifera has been developed using a Cameca ims 1270 ion microprobe. In situ ??Li analyses have been performed in biogenic calcite of planktonic foraminifera from various locations. Results show that for west Pacific mixed Globigerinoides and Globorotalia (22°S161°E), the isotopic variability between tests and within a single test, respectively, is not significantly greater than estimated analytical uncertainty (?1.5‰). Mean ??Li for several plan...

  6. Customised search and comparison of in situ, satellite and model data for ocean modellers

    Science.gov (United States)

    Hamre, Torill; Vines, Aleksander; Lygre, Kjetil

    2014-05-01

    For the ocean modelling community, the amount of available data from historical and upcoming in situ sensor networks and satellite missions, provides an rich opportunity to validate and improve their simulation models. However, the problem of making the different data interoperable and intercomparable remains, due to, among others, differences in terminology and format used by different data providers and the different granularity provided by e.g. in situ data and ocean models. The GreenSeas project (Development of global plankton data base and model system for eco-climate early warning) aims to advance the knowledge and predictive capacities of how marine ecosystems will respond to global change. In the project, one specific objective has been to improve the technology for accessing historical plankton and associated environmental data sets, along with earth observation data and simulation outputs. To this end, we have developed a web portal enabling ocean modellers to easily search for in situ or satellite data overlapping in space and time, and compare the retrieved data with their model results. The in situ data are retrieved from a geo-spatial repository containing both historical and new physical, biological and chemical parameters for the Southern Ocean, Atlantic, Nordic Seas and the Arctic. The satellite-derived quantities of similar parameters from the same areas are retrieved from another geo-spatial repository established in the project. Both repositories are accessed through standard interfaces, using the Open Geospatial Consortium (OGC) Web Map Service (WMS) and Web Feature Service (WFS), and OPeNDAP protocols, respectively. While the developed data repositories use standard terminology to describe the parameters, especially the measured in situ biological parameters are too fine grained to be immediately useful for modelling purposes. Therefore, the plankton parameters were grouped according to category, size and if available by element. This grouping was reflected in the web portal's graphical user interface, where the groups and subgroups were organized in a tree structure, enabling the modeller to quickly get an overview of available data, going into more detail (subgroups) if needed or staying at a higher level of abstraction (merging the parameters below) if this provided a better base for comparison with the model parameters. Once a suitable level of detail, as determined by the modeller, was decided, the system would retrieve available in situ parameters. The modellers could then select among the pre-defined models or upload his own model forecast file (in NetCDF/CF format), for comparison with the retrieved in situ data. The comparison can be shown in different kinds of plots (e.g. scatter plots), through simple statistical measures or near-coincident values of in situ of model points can be exported for further analysis in the modeller's own tools. During data search and presentation, the modeller can determine both query criteria and what associated metadata to include in the display and export of the retrieved data. Satellite-derived parameters can be queried and compared with model results in the same manner. With the developed prototype system, we have demonstrated that a customised tool for searching, presenting, comparing and exporting ocean data from multiple platforms (in situ, satellite, model), makes it easy to compare model results with independent observations. With further enhancement of functionality and inclusion of more data, we believe the resulting system can greatly benefit the wider community of ocean modellers looking for data and tools to validate their models.

  7. A novel in situ gel for sustained drug delivery and targeting.

    Science.gov (United States)

    Ganguly, Sudipta; Dash, Alekha K

    2004-05-19

    The objective of this study was to develop a novel chitosan-glyceryl monooleate (GMO) in situ gel system for sustained drug delivery and targeting. The delivery system consisted of 3% (w/v) chitosan and 3% (w/v) GMO in 0.33M citric acid. In situ gel was formed at a biological pH. In vitro release studies were conducted in Sorensen's phosphate buffer (pH 7.4) and drugs were analyzed either by HPLC or spectrophotometry. Characterization of the gel included the effect of cross-linker, determination of diffusion coefficient and water uptake by thermogravimetric analysis (TGA). Mucoadhesive property of the gel was evaluated in vitro using an EZ-Tester. Incorporation of a cross-linker (glutaraldehyde) retarded the rate and extent of drug release. The in vitro release can further be sustained by replacing the free drug with drug-encapsulated microspheres. Drug release from the gel followed a matrix diffusion controlled mechanism. Inclusion of GMO enhanced the mucoadhesive property of chitosan by three- to sevenfold. This novel in situ gel system can be useful in the sustained delivery of drugs via oral as well as parenteral routes. PMID:15113617

  8. Evaluation of in situ remedial technologies for sites contaminated with hydrocarbons. Final report

    International Nuclear Information System (INIS)

    This report presents the results of an extensive literature review that was performed to assess the overall effectiveness, applicability, and limitations of the various in situ technologies currently being applied to remediate sites contaminated by petroleum hydrocarbons. Of 17 technologies that were identified in an initial review and database search, nine were selected as widely used or promising for increased future use: soil vapor extraction, bioventing, pump and treat, aquifer air sparging, biosparging, in situ enhanced aquifer bioremediation, natural attenuation, in-well aeration, and dual-phase extraction. Following a general discussion of in situ technology, the report devotes one chapter to each of these nine technologies, presenting in each chapter a description of the technology; criteria to be used in considering applicability of the technology at a site; a discussion of design criteria and operating conditions; a strategy for monitoring remediation and determining when clean-up criteria are met; a discussion of performance-related issues; documented case studies; and a hypothetical application of the technology. Report appendices provide an overview of petroleum hydrocarbon constituents and their properties, and a glossary of terms

  9. Seismic monitoring of in situ combustion process in a heavy oil field

    International Nuclear Information System (INIS)

    Three time-lapse 3D seismic surveys are analysed to monitor the effect of in situ combustion, a thermal-enhanced oil recovery process in the Balol heavy oil reservoir in India. The baseline data were acquired prior to the start of the in situ combustion process in four injection wells, while the two monitor surveys were acquired 1 and 2 years after injection start, respectively. We present the results of baseline and second monitor surveys. Fluid substitution studies based on acoustic well logs predict a seismic amplitude decrease at the top reservoir and an increase at the base reservoir. Both the amplitude dimming at the top reservoir and the brightening at the base reservoir are observed in the field data. The extent of the most pronounced 4D anomaly is estimated from the seismic amplitude and time shift analysis. The interesting result of seismic analysis is that the anomalies are laterally shifted towards the northwest, rather than the expected east, from the injector location suggesting a northwest movement of the in situ combustion front. No clear evidence of air leakage into other sand layers, neither above nor below the reservoir sand, is observed. This does not necessarily mean that all the injected air is following the reservoir sand, especially if the thief sand layers are thin. These layers might be difficult to observe on seismic data

  10. A Comparative Study of In Situ and Ex Situ Impregnation for LLDPE/Silica Composites Production

    Directory of Open Access Journals (Sweden)

    Bunjerd Jongsomjit

    2012-01-01

    Full Text Available The two different kinds of impregnation (in situ and ex situ were used in the heterogeneous copolymerization of ethylene and 1-hexene for production of LLDPE/silica composite. For the ex situ impregnation, MMAO cocatalyst was immobilized firmly onto the silica support through washing and drying step before introducing the powder of MMAO/silica support into the copolymerization system. For the in situ impregnation, MMAO was only contacted with silica support for the short period of time before bringing all of the slurry of MMAO/silica support into the copolymerization system. By comparing the catalytic activity between two methods, it was found that the in situ impregnation provided the higher one beneficial from the lower interaction between MMAO and silica due to lower contacting time. The lower interaction enhanced the reactivity of MMAO toward zirconocene catalyst during activation process thus leading to the higher catalytic activity. The said interaction can be proven by thermal gravimetric analysis (TGA and X-ray photoelectron spectroscopy (XPS analysis. In addition, the obtained polymers were further characterized by means of scanning electron microscopy (SEM, 13C-NMR spectroscopy (NMR and differential scanning calorimetry (DSC.

  11. Modeling in-situ uranium(VI) bioreduction by sulfate-reducing bacteria

    Science.gov (United States)

    Luo, Jian; Weber, Frank-Andreas; Cirpka, Olaf A.; Wu, Wei-Min; Nyman, Jennifer L.; Carley, Jack; Jardine, Philip M.; Criddle, Craig S.; Kitanidis, Peter K.

    2007-06-01

    We present a travel-time based reactive transport model to simulate an in-situ bioremediation experiment for demonstrating enhanced bioreduction of uranium(VI). The model considers aquatic equilibrium chemistry of uranium and other groundwater constituents, uranium sorption and precipitation, and the microbial reduction of nitrate, sulfate and U(VI). Kinetic sorption/desorption of U(VI) is characterized by mass transfer between stagnant micro-pores and mobile flow zones. The model describes the succession of terminal electron accepting processes and the growth and decay of sulfate-reducing bacteria, concurrent with the enzymatic reduction of aqueous U(VI) species. The effective U(VI) reduction rate and sorption site distributions are determined by fitting the model simulation to an in-situ experiment at Oak Ridge, TN. Results show that (1) the presence of nitrate inhibits U(VI) reduction at the site; (2) the fitted effective rate of in-situ U(VI) reduction is much smaller than the values reported for laboratory experiments; (3) U(VI) sorption/desorption, which affects U(VI) bioavailability at the site, is strongly controlled by kinetics; (4) both pH and bicarbonate concentration significantly influence the sorption/desorption of U(VI), which therefore cannot be characterized by empirical isotherms; and (5) calcium-uranyl-carbonate complexes significantly influence the model performance of U(VI) reduction.

  12. In situ SiN passivation of AlInN/GaN heterostructures by MOVPE

    International Nuclear Information System (INIS)

    AlInN is being considered to replace AlGaN as barrier material in high-electron mobility transistors (HEMT) mainly due to the possibility to downscale the barrier layer thickness at coexistent higher drain current density. However, the stability of surface conditions which can strongly influence the electrical properties of the device has to be assured. In situ deposition of a SiN passivation layer by metal-organic vapour phase epitaxy (MOVPE) is therefore a promising candidate to improve the device structure. In this paper, heterostructures with thin AlInN barrier passivated by in situ deposition of SiN layers of different thicknesses are presented. As expected, deterioration of the sheet resistance (RSh) was observed for the reference sample without SiN passivation layer by continuously performed RSh mappings of the investigated wafer. This change is noticeably reduced for samples with in situ SiN passivation layer. A comparison of two wafers, stored either with or without air exposure, reveals oxidation as presumable reason for the deterioration. Further, results from RSh measurements on processed wafers indicate an enhanced RSh stability during process for SiN-capped samples. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Evidence for the microbial in situ conversion of oil to methane in the Dagang oilfield

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, N.; Richnow, H.H. [Helmholtz-Zentrum fuer Umweltforschung (UFZ), Leipzig (Germany). Abt. Isotopenbiogeochemie; Cai, M. [Helmholtz-Zentrum fuer Umweltforschung (UFZ), Leipzig (Germany). Abt. Isotopenbiogeochemie; University of Science and Technology, Beijing (China). School of Civil and Environment Engineering; Straaten, N.; Krueger, M. [Bundesanstalt fuer Geowissenschaften und Rohstoffe BGR Geozentrum (BGR), Hannover (Germany). Fachbereich Geochemie der Rohstoffe; Yao, Jun [University of Science and Technology, Beijing (China). School of Civil and Environment Engineering

    2013-08-01

    In situ biotransformation of oil to methane was investigated in a reservoir in Dagang, China using chemical fingerprinting, isotopic analyses, and molecular and biological methods. The reservoir is highly methanogenic despite chemical indications of advanced oil degradation, such as depletion of n-alkanes, alkylbenzenes, and light polycyclic aromatic hydrocarbon (PAHs) fractions or changes in the distribution of several alkylated polycyclic aromatic hydrocarbons. The degree of degradation strongly varied between different parts of the reservoir, ranging from severely degraded to nearly undegraded oil compositions. Geochemical data from oil, water and gas samples taken from the reservoir are consistent with in situ biogenic methane production linked to aliphatic and aromatic hydrocarbon degradation. Microcosms were inoculated with production and injection waters in order to characterize these processes in vitro. Subsequent degradation experiments revealed that autochthonous microbiota are capable of producing methane from {sup 13}C-labelled n-hexadecane or 2-methylnaphthalene, and suggest that further methanogenesis may occur from the aromatic and polyaromatic fractions of Dagang reservoir fluids. The microbial communities from produced oil-water samples were composed of high numbers of microorganisms (on the order to 10{sup 7}), including methane-producing Archaea within the same order of magnitude. In summary, the investigated sections of the Dagang reservoir may have significant potential for testing the viability of in situ conversion of oil to methane as an enhanced recovery method, and biodegradation of the aromatic fractions of the oil may be an important methane source. (orig.)

  14. In situ X-ray diffraction of oxide scales on high-temperature materials

    International Nuclear Information System (INIS)

    The subject of this dissertation is examination of high-temperature oxidation processes primarily by in situ X-ray diffraction, accompanied by metallographic and microprobe analyses. The studies reported focus on two major aspects: Time and temperature-resolved investigation of the behaviour of nickel-base alloys intended for use as turbine blade materials, as some of the processes contributing to their complex oxidation behaviour can only be revealed by in situ analysis; and temperature-resolved detection of mechanical stresses in oxide scales. For this last task, a novel parallel-ray optics with a Goebel mirror was used, in order to avoid measuring errors due to the high-temperature system conditions. The nickel-base alloys DS CM247 LC and CMSX4 were examined for their oxidation behaviour because they are candidate materials of interest to the gas turbine industry. The stress analyses were performed with the iron-base alloy PM 2000 prepared by powder metallurgy, because oxidation processes on PM 2000 form a homogeneous ?-Al2O3 layer as from 1000 C upward, thus offering good prospects for gaining enhanced insight into the processes involved, and for further developing the methodology for in situ stress analysis. (orig./CB)

  15. Novel thermosensitive in situ gel based on poloxamer for uterus delivery.

    Science.gov (United States)

    Lu, Chaocheng; Liu, Mengjiao; Fu, Hualin; Zhang, Wei; Peng, Guangneng; Zhang, Yanli; Cao, Hang; Luo, Li

    2015-09-18

    Side effects and drug residues are major concerns affecting hormone therapy of bovine reproductive diseases. Fertility-promoting intrauterine infusion liquid (FPL), an effective alternative to hormone therapy, is associated with short retention time and low therapeutic efficacy. To address these problems, we developed a thermosensitive in situ gel based on poloxamer 407 for local uterine administration. To achieve the desired gelling temperature and enhance local retention property, we added poloxamer 188 and HPMC to the formulation containing poloxamer 407 and FPL. After screening was performed, the optimized formulation showed good temperature sensitivity in vitro and in vivo. Gelation temperature was approximately 27°C. In vitro release tests showed that icariin (the major active compound in FPL) was slow released from in situ forming gel. After the gel was locally administered, uterine and ovarian indexes were significantly increased in the gel group compared with the control group (Pgel group was significantly higher than that of the control group (Pgel group. Therefore, the proposed in situ forming gel system based on poloxamer 407 is a promising local drug delivery system to treat bovine uterine diseases. PMID:25981887

  16. An overview on in situ micronization technique – An emerging novel concept in advanced drug delivery

    Science.gov (United States)

    Vandana, K.R.; Prasanna Raju, Y.; Harini Chowdary, V.; Sushma, M.; Vijay Kumar, N.

    2013-01-01

    The use of drug powders containing micronized drug particles has been increasing in several pharmaceutical dosage forms to overcome the dissolution and bioavailability problems. Most of the newly developed drugs are poorly water soluble which limits dissolution rate and bioavailability. The dissolution rate can be enhanced by micronization of the drug particles. The properties of the micronized drug substance such as particle size, size distribution, shape, surface properties, and agglomeration behaviour and powder flow are affected by the type of micronization technique used. Mechanical communition, spray drying and supercritical fluid (SCF) technology are the most commonly employed techniques for production of micronized drug particles but the characteristics of the resulting drug product cannot be controlled using these techniques. Hence, a newer technique called in situ micronization is developed in order to overcome the limitations associated with the other techniques. This review summarizes the existing knowledge on in situ micronization techniques. The properties of the resulting drug substance obtained by in situ micronization were also compared. PMID:25161371

  17. An overview on in situ micronization technique - An emerging novel concept in advanced drug delivery.

    Science.gov (United States)

    Vandana, K R; Prasanna Raju, Y; Harini Chowdary, V; Sushma, M; Vijay Kumar, N

    2014-09-01

    The use of drug powders containing micronized drug particles has been increasing in several pharmaceutical dosage forms to overcome the dissolution and bioavailability problems. Most of the newly developed drugs are poorly water soluble which limits dissolution rate and bioavailability. The dissolution rate can be enhanced by micronization of the drug particles. The properties of the micronized drug substance such as particle size, size distribution, shape, surface properties, and agglomeration behaviour and powder flow are affected by the type of micronization technique used. Mechanical communition, spray drying and supercritical fluid (SCF) technology are the most commonly employed techniques for production of micronized drug particles but the characteristics of the resulting drug product cannot be controlled using these techniques. Hence, a newer technique called in situ micronization is developed in order to overcome the limitations associated with the other techniques. This review summarizes the existing knowledge on in situ micronization techniques. The properties of the resulting drug substance obtained by in situ micronization were also compared. PMID:25161371

  18. Influence of basement structures on in situ stresses over the Surat Basin, southeast Queensland

    Science.gov (United States)

    Brooke-Barnett, Samuel; Flottmann, Thomas; Paul, Pijush K.; Busetti, Seth; Hennings, Peter; Reid, Ray; Rosenbaum, Gideon

    2015-07-01

    The Jurassic to Cretaceous sedimentary rocks of the Surat Basin in southeast Queensland host a significant volume of coal seam gas resources. Consequently, knowledge of the in situ stress is important for coal permeability enhancement and wellbore stability. Using wireline log data and direct stress measurements, we have calculated stress orientations from 36 wells and stress magnitudes from 7 wells across the Surat Basin. Our results reveal a relationship between high tectonic stress and proximity to structures within the underlying "basement" rocks. The influence of tectonic stresses is diminished with depth in areas with thicker sedimentary cover that are relatively far from the basement structures. We suggest that this relationship is due to the redistribution of in situ stresses around areas where basement is shallower and where basement structures, such as the Leichhardt-Burunga Fault System, are present. This behavior is explained by a lower rigidity in the thickest basin cover, which reduces the ability to maintain higher tectonic stress. Over the entire Surat Basin, a significant amount of variability in in situ stress orientation is observed. The authors attribute this stress variability to complex plate boundary interactions on the northern and eastern margins of the Indo-Australian Plate.

  19. Atomic Structure of Pt3Ni Nanoframe Electrocatalysts by in Situ X-ray Absorption Spectroscopy.

    Science.gov (United States)

    Becknell, Nigel; Kang, Yijin; Chen, Chen; Resasco, Joaquin; Kornienko, Nikolay; Guo, Jinghua; Markovic, Nenad M; Somorjai, Gabor A; Stamenkovic, Vojislav R; Yang, Peidong

    2015-12-23

    Understanding the atomic structure of a catalyst is crucial to exposing the source of its performance characteristics. It is highly unlikely that a catalyst remains the same under reaction conditions when compared to as-synthesized. Hence, the ideal experiment to study the catalyst structure should be performed in situ. Here, we use X-ray absorption spectroscopy (XAS) as an in situ technique to study Pt3Ni nanoframe particles which have been proven to be an excellent electrocatalyst for the oxygen reduction reaction (ORR). The surface characteristics of the nanoframes were probed through electrochemical hydrogen underpotential deposition and carbon monoxide electrooxidation, which showed that nanoframe surfaces with different structure exhibit varying levels of binding strength to adsorbate molecules. It is well-known that Pt-skin formation on Pt-Ni catalysts will enhance ORR activity by weakening the binding energy between the surface and adsorbates. Ex situ and in situ XAS results reveal that nanoframes which bind adsorbates more strongly have a rougher Pt surface caused by insufficient segregation of Pt to the surface and consequent Ni dissolution. In contrast, nanoframes which exhibit extremely high ORR activity simultaneously demonstrate more significant segregation of Pt over Ni-rich subsurface layers, allowing better formation of the critical Pt-skin. This work demonstrates that the high ORR activity of the Pt3Ni hollow nanoframes depends on successful formation of the Pt-skin surface structure. PMID:26652294

  20. Analytical Model for the Diffusion Process in a In-Situ Combustion Tube

    Science.gov (United States)

    Gutierrez, Patricia; Reyes, Adrian

    2015-03-01

    The in-situ combustion process (ISC) is basically an air or oxygen enriched gas injection oil recovery process, inside an extraction well. In contrast to a conventional gas injection process, an ISC process consists in using heat to create a combustion front that raises the fuel temperature, decreasing its viscosity, making extraction easier. The oil is taken toward the productor by means of a vigorous gas thrust as well as a water thrust. To improve and enhance this technique in the field wells, it has been widely perform experimental laboratory tests, in which an in-situ combustion tube is designed to simulate the extraction process. In the present work we propose to solve analytically the problem, with a parabolic partial differential equation associated to the convection-diffusion phenomenon, equation which describes the in-situ combustion process. The whole mathematical problem is established by completing this equation with the correspong boundary and initial conditions, the thickness of the combustion zone, flow velocity, and more parameters. The theoretically obtained results are compared with those reported in literature. We further, fit the parameter of our model to the mentioned data taken from the literature.

  1. Hydrogen production by glycerol steam reforming with in situ hydrogen separation: A thermodynamic investigation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaodong [Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Chemical Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, Scotland (United Kingdom); Wang, Na [Chemical Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, Scotland (United Kingdom); Li, Maoshuai; Li, Shuirong; Wang, Shengping; Ma, Xinbin [Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

    2010-10-15

    Thermodynamic features of hydrogen production by glycerol steam reforming with in situ hydrogen extraction have been studied with the method of Gibbs free energy minimization. The effects of pressure (1-5 atm), temperature (600-1000 K), water to glycerol ratio (WGR, 3-12) and fraction of H{sub 2} removal (f, 0-1) on the reforming reactions and carbon formation were investigated. The results suggest separation of hydrogen in situ can substantially enhance hydrogen production from glycerol steam reforming, as 7 mol (stoichiometric value) of hydrogen can be obtained even at 600 K due to the hydrogen extraction. It is demonstrated that atmospheric pressure and a WGR of 9 are suitable for hydrogen production and the optimum temperature for glycerol steam reforming with in situ hydrogen removal is between 825 and 875 K, 100 K lower than that achieved typically without hydrogen separation. Furthermore, the detrimental influence of increasing pressure in terms of hydrogen production becomes marginal above 800 K with a high fraction of H{sub 2} removal (i.e., f = 0.99). High temperature and WGR are favorable to inhibit carbon production. (author)

  2. In situ leaching of uranium: Technical, environmental and economic aspects

    International Nuclear Information System (INIS)

    Within the framework of its activities in nuclear raw materials the International Atomic Energy Agency has convened a series of meetings to discuss various aspects of uranium ore processing technology, recovery of uranium from non-conventional resources and development of projects for the production of uranium concentrates including economic aspects. As part of this continuing effort to discuss and document important aspects of uranium production the IAEA convened a Technical Committee Meeting on Technical, Economic and Environmental Aspects of In-Situ Leaching. Although the use of this technique is limited by geological and economic constraints, it has a significant potential to produce uranium at competitive prices. This is especially important in the current uranium market which is mainly characterised by large inventories, excess production capability and low prices. This situation is not expected to last indefinitely but it is unlikely to change drastically in the next ten years or so. This Technical Committee Meeting was held in Vienna from 3 to 6 November 1987 with the attendance of 24 participants from 12 countries. Eight papers were presented. Technical sessions covered in-situ mining research, environmental and licensing aspects and restoration of leached orebodies; the technological status of in-situ leaching, the current status and future prospects of in-situ leaching of uranium in Member States, general aspects of planning and implementation of in-situ projects and the economics of in-situ leaching. Refs, figs and tabs

  3. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-compound DNAPLs with surfactant solutions. Phase 1: Laboratory and pilot field-scale testing. Phase 2: Solubilization test and partitioning interwell tracer tests. Final report

    International Nuclear Information System (INIS)

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). The field test was conducted in the alluvial aquifer which is located 20 to 30 meters beneath a vapor degreasing operation at Paducah Gaseous Diffusion Plant. This aquifer has become contaminated with TCE due to leakage of perhaps 40,000 liters of TCE, which has generated a plume of dissolved TCE extending throughout an area of approximately 3 km2 in the aquifer. Most of the TCE is believed to be present in the overlying lacustrine deposits and in the aquifer itself as a dense, non-aqueous phase liquid, or DNAPL. The objective of the field test was to assess the efficacy of the surfactant for in situ TCE solubilization. Although the test demonstrated that sorbitan monooleate was unsuitable as a solubilizer in this aquifer, the single-well test was demonstrated to be a viable method for the in situ testing of surfactants or cosolvents prior to proceeding to full-scale remediation

  4. The in-situ decontamination of sand and gravel aquifers by chemically enhanced solubilization of multiple-compound DNAPLs with surfactant solutions: Phase 1 -- Laboratory and pilot field-scale testing and Phase 2 -- Solubilization test and partitioning and interwell tracer tests. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-24

    Laboratory, numerical simulation, and field studies have been conducted to assess the potential use of micellar-surfactant solutions to solubilize chlorinated solvents contaminating sand and gravel aquifers. Ninety-nine surfactants were screened for their ability to solubilize trichloroethene (TCE), perchloroethylene (PCE), and carbon tetrachloride (CTET). The field test was conducted in the alluvial aquifer which is located 20 to 30 meters beneath a vapor degreasing operation at Paducah Gaseous Diffusion Plant. This aquifer has become contaminated with TCE due to leakage of perhaps 40,000 liters of TCE, which has generated a plume of dissolved TCE extending throughout an area of approximately 3 km{sup 2} in the aquifer. Most of the TCE is believed to be present in the overlying lacustrine deposits and in the aquifer itself as a dense, non-aqueous phase liquid, or DNAPL. The objective of the field test was to assess the efficacy of the surfactant for in situ TCE solubilization. Although the test demonstrated that sorbitan monooleate was unsuitable as a solubilizer in this aquifer, the single-well test was demonstrated to be a viable method for the in situ testing of surfactants or cosolvents prior to proceeding to full-scale remediation.

  5. In situ composite of nano SiO2-P(VDF-HFP) porous polymer electrolytes for Li-ion batteries

    International Nuclear Information System (INIS)

    Nano SiO2-P(VDF-HFP) composite porous membranes were prepared as the matrix of porous polymer electrolytes through in situ composite method based on hydrolysis of tetraethoxysilane and phase inversion. SEM, TEM, DSC and AC impedance analysis were carried out. It is found that the in situ prepared nano silica was homogeneously dispersed in the polymeric matrix, enhanced conductivity and electrochemical stability of porous polymer electrolytes, and improved the stability of the electrolytes against lithium metal electrodes. The in situ composite method was found to be much better than the direct composite method in lowering the interfacial resistance between electrolyte and lithium metal electrode. Moreover, cycle test of lithium batteries using lithium metal as anode and sulfur composite material as cathode showed that the electrolyte based on in situ composite of silica presented stable charge-discharge behavior and little capacity loss of battery

  6. Advances in Groundwater Remediation: Achieving Effective In Situ Delivery of Chemical Oxidants and Amendments

    DEFF Research Database (Denmark)

    Siegrist, Robert L.; Crimi, Michelle

    2012-01-01

    Contamination of soil and groundwater by organic chemicals represents a major environmental problem in urban areas throughout the United States and other industrialized nations. In situ chemical oxidation (ISCO) has emerged as one of several viable methods for remediation of organically contaminated sites. Many of the most prevalent organic contaminants of concern at sites in urban areas (e.g., chlorinated solvents, motor and heating fuels) can be destroyed using catalyzed hydrogen peroxide (H 2 O 2 ), potassium permanganate (KMnO 4 ), sodium persulfate (Na 2 S 2 O 8 ), or ozone (O 3 ) delivered into the subsurface using injection wells, probes, or other techniques. A continuing challenge for ISCO, as well as other in situ remediation technologies, is how to achieve in situ delivery and obtain simultaneous contact between treatment fl uids, such as oxidants and amendments, and the target contaminants. During the past few years, advances have been made in several key areas including knowledge and know-how associated with: (1) use of amendments for enhanced delivery and distribution of treatment fl uids in heterogeneous settings with zones of low permeability media, (2) use of direct push technology for targeted high resolution delivery of treatment fl uids, and (3) use of monitoring and sensing methods for direct feedback for delivery control and evaluation of remediation effectiveness. This paper provides a summary of ISCO and highlights ongoing efforts to advance the effective in situ delivery of treatment fl uids, with an emphasis on chemical oxidants and amendments, which can help achieve cleanup goals and protect groundwater and associated drinking water resources.

  7. In-situ fluorometry for dispersant effectiveness monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Tan, S.H. [Oil Spill Response Ltd., Singapore, (Singapore)

    2009-07-01

    The use of chemical dispersant for oil spills on water is often a preferred response option because it reduces the overall environmental impact by reducing the likelihood of shoreline impact. Dispersants consist of a solvent carrier and a surfactant to enhance the natural dispersion processes of spilled oil. They generate large amounts of tiny oil droplets, producing a coffee-coloured plume under the water surface. When dispersant is applied, its effectiveness must be verified continually so that the response can be terminated as soon as the dispersant is no longer effective. This is normally done by visual observation, but this may be impaired due to poor weather or light conditions, high sediment content in waters and when dispersing pale-coloured oils. This paper demonstrated that advancement in detection and communication technology has made it possible to monitor dispersed oil in water column in a more scientific manner using instrumentation that provides real-time feedback to the incident command centre to help in the decision making process. Oil Spill Response Limited has acquired the capability to conduct in-situ fluorometry monitoring. The system consists of a solid state fluorometer, a laptop with built in global positioning system (GPS), a georeferencing software and satellite communication. The system provides a qualitative indication of a relative increase of oil in the water column, the location of monitoring points and high quality images that can be delivered to clients via Internet. This paper reported on results of a recent deployment of the system in an offshore oil response operation in Australia. The lessons learned were discussed along with the limitation and operational challenges of the system. Fluorometry was shown to be a sensitive but not necessarily accurate means of oil determination. 25 refs., 5 figs.

  8. In situ powder diffraction study of belite sulfoaluminate clinkering.

    Science.gov (United States)

    De la Torre, Angeles G; Cuberos, Antonio J M; Alvarez-Pinazo, Gema; Cuesta, Ana; Aranda, Miguel A G

    2011-05-01

    Belite sulfoaluminate (BSA) cements have been proposed as environmentally friendly building materials, as their production may release up to 35% less CO(2) into the atmosphere when compared with ordinary Portland cement fabrication. However, their formation mechanism has not been studied in detail so far. Here, an in situ high-temperature high-resolution synchrotron X-ray powder diffraction study is reported. Two types of BSA clinkers have been characterized, both containing 50-60 wt% C(2)S and 20-30 wt% C(4)A(3)\\underline{\\rm S} as main phases. One type is iron-rich and a second type (with different phase assemblage) is aluminium-rich. Furthermore, the C(2)S phase reacts slowly with water, thus activation of this compound is desirable in order to enhance the mechanical strength development of the resulting cements. To do so, iron-rich BSA clinkers have been doped with minor amounts of B(2)O(3) and Na(2)O to promote stabilization of ?-forms of C(2)S, which are more reactive with water. The decarbonated raw materials were loaded into Pt tubes and heated to between 973 K and 1673 K, and patterns were collected using a high-energy synchrotron beam of wavelength ? = 0.30 Å. The thermal stability of Klein's salt in these clinkers has been clarified. Several reactions have been followed: formation and decomposition of Klein's salt, melting of aluminates and ferrite, and polymorphic transformations of dicalcium silicate: alpha'H-C2S ? ?-C(2)S. Changes in mineralogical phase assemblages at a given temperature owing to the addition of minor amounts of selected elements have also been determined. PMID:21525661

  9. Chelator induced phytoextraction and in situ soil washing of Cu

    International Nuclear Information System (INIS)

    In a soil column experiment, we investigated the effect of 5 mmol kg-1 soil addition of citric acid, ethylenediamine tetraacetate (EDTA), diethylenetriamine-pentaacetate (DTPA) and [S,S]-stereoisomer of ethylenediamine-disuccinate (EDDS) on phytoextraction of Cu from a vineyard soil with 162.6 mg kg-1 Cu, into the test plant Brassica rapa var. pekinensis. We also examined the use of a horizontal permeable barrier, composed of layers of nutrient enriched sawdust and apatite, for reduction of chelator induced Cu leaching. The addition of all chelators, except citric acid, enhanced Cu mobility and caused leaching of 19.5-23% of initial total Cu from the soil column. However, Cu plant uptake did not increase accordingly; the most effective was the EDDS treatment, in which plant Cu concentration reached 37.8±1.3 mg kg-1 Cu and increased by 3.3-times over the control treatment. The addition of none of the chelators in the concentration range from 5 to 15 mmol kg-1 exerted any toxic effect on respiratory soil microorganisms. When EDDS was applied into the columns with horizontal permeable barriers, only 0.53±0.32% of the initial total Cu was leached. Cu (36.7%) was washed from the 18 cm soil layer above the barrier and accumulated in the barrier. Our results indicate that rather than for a reduction of Cu leaching during rather ineffective chelate induced Cu phytoextraction, horizontal permeable barriers could be more effective in a new remediation technique of controlled in situ soil washing of Cu with biodegradable chelates

  10. Comparison of Fluorescence In Situ Hybridization and Chromogenic In Situ Hybridization for Low and High Throughput HER2 Genetic Testing

    DEFF Research Database (Denmark)

    Poulsen, Tim S; Espersen, Maiken Lise Marcker; Kofoed, Vibeke; Dabetic, Tanja; Høgdall, Estrid; Balslev, Eva

    2013-01-01

    The purpose was to evaluate and compare 5 different HER2 genetic assays with different characteristics that could affect the performance to analyze the human epidermal growth factor 2 (HER2) gene copy number under low and high throughput conditions. The study included 108 tissue samples from breast cancer patients with HER2 immunohistochemistry (IHC) results scored as 0/1+, 2+, and 3+. HER2 genetic status was analysed using chromogenic in situ hybridization (CISH) and fluorescence in situ hybrid...

  11. In situ PCR detection and significance of IL-3 gene expression in irradiated hematopoietic cells of mouse bone marrow

    International Nuclear Information System (INIS)

    Objective: To study the significance of endogenous interleukin 3(IL-3) gene expression in repair of irradiated mouse bone marrow. Methods: Seventy-eight LACA mice were subjected to total body irradiation with 60Co ?-rays and were sacrificed within 4 weeks after irradiation. The bone marrow histopathological sections were stained with HE, and the expression of endogenous IL-3 gene was detected by means of immunocytochemistry,in situ hybridization(ISH) and in situ reverse transcription PCR(IS RT-PCR). Results: Obvious injury of bone marrow occurred after irradiation and then recovered within 4 weeks. IL-3 protein was obviously increased in the cytoplasm of recovering hematopoietic cells(HCs), especially on day 21 after irradiation, while its mRNA was poorly positive by ISH on days 10-21, especially day 15.IS RT-PCR showed that IL-3 mRNA was strongly positive in recovering HCs cytoplasm, especially on days 10 to 15. Conclusion: In situ RT-PCR can objectively reflect the regulation of IL-3 gene expression in bone marrow after irradiation, and the expression of endogenous IL-3 gene may play an important role in hematopoietic reconstruction of irradiated bone marrow

  12. In situ Evidence of Defect Cluster Absorption by Grain Boundaries in Kr Ion Irradiated Nanocrystalline Ni

    Science.gov (United States)

    Sun, C.; Song, M.; Yu, K. Y.; Chen, Y.; Kirk, M.; Li, M.; Wang, H.; Zhang, X.

    2013-04-01

    Significant microstructural damage, in the form of defect clusters, typically occurs in metals subjected to heavy ion irradiation. High angle grain boundaries (GBs) have long been postulated as sinks for defect clusters, like dislocation loops. Here, we provide direct evidence, via in situ Kr ion irradiation within a transmission electron microscope, that high angle GBs in nanocrystalline (NC) Ni, with an average grain size of ~55 nm, can effectively absorb irradiation-induced dislocation loops and segments. These high angle GBs significantly reduce the density and size of irradiation-induced defect clusters in NC Ni compared to their bulk counterparts, and thus NC Ni achieves significant enhancement of irradiation tolerance.

  13. Methods of producing alkylated hydrocarbons from an in situ heat treatment process liquid

    Science.gov (United States)

    Roes, Augustinus Wilhelmus Maria (Houston, TX); Mo, Weijian (Sugar Land, TX); Muylle, Michel Serge Marie (Houston, TX); Mandema, Remco Hugo (Houston, TX); Nair, Vijay (Katy, TX)

    2009-09-01

    A method for producing alkylated hydrocarbons is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce at least a second gas stream including hydrocarbons having a carbon number of at least 3. The first gas stream and the second gas stream are introduced into an alkylation unit to produce alkylated hydrocarbons. At least a portion of the olefins in the first gas stream enhance alkylation.

  14. Beam-assisted large elongation of in situ formed Li2O nanowires

    OpenAIRE

    ZHENG, HE; Liu, Yang; Mao, Scott X.; Wang, Jianbo; Huang, Jian Yu

    2012-01-01

    As an important component of the solid electrolyte interface in lithium ion batteries and an effective blanket breeding material in fusion reactor, the mechanical property of Li2O is of great interest but is not well understood. Here we show that the polycrystalline Li2O nanowires were formed in situ by touching and pulling lithium hydroxide under electron beam (e-beam) illumination. The Li2O nanowires sustained an enhanced elongation (from 80% to 176%) under low dose e-beam irradiation near ...

  15. Fiber optic Raman spectrograph for in situ environmental monitoring. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Carrabba, M.M. [EIC Labs., Inc., Norwood, MA (United States)

    1992-11-01

    This report discusses the development and testing of a small laboratory prototype, field Raman spectrometer which can be used with a fiber optic sampling probe incorporting substrates tailored for surface enhanced Raman spectroscopy (SERS) for low level detection of chemical species. The report also discusses demonstration of apparatus for both laboratory and field environmental samples typical of DOE environmental restoration sites. Preliminary results establish a new technique which can be used in,the field to identify and profile in situ a wide variety of pollutants at the action levels required for remediation.

  16. In situ transmission electron microscope observation of the formation of fuzzy structures on tungsten

    International Nuclear Information System (INIS)

    To investigate the formation processes of tungsten nano-structures, so called fuzz, in situ transmission electron microscope observations during helium ion irradiation and high temperature annealing have been performed. The irradiation with 3 keV He+ from room temperature to 1273 K is found to cause high-density helium bubbles in tungsten with no significant change in the surface structure. At higher temperatures, surface morphology changes were observed even without helium irradiation due probably to surface diffusion of tungsten atoms driven by surface tension. It is clearly shown that this morphology change is enhanced with helium irradiation, i.e. the formation of helium bubbles. (paper)

  17. In situ synthesis of mixed-valent manganese oxide nanocrystals: an in situ synchrotron X-ray diffraction study.

    Science.gov (United States)

    Shen, Xiong-Fei; Ding, Yun-Shuang; Hanson, Jonathan C; Aindow, Mark; Suib, Steven L

    2006-04-12

    Phase transformations of materials can be studied by in situ synchrotron X-ray diffraction. However, most reported in situ synchrotron XRD studies focus on solid state/gel systems by measuring phase/structure changes during application of pressure or heat. Phase transformations during material synthesis and their applications, especially in wet chemistry processes with different media, have not drawn much attention. Here, using manganese oxides as examples, we report the successful characterization of phase transformations in in situ hydrothermal synthesis conditions by the in situ synchrotron XRD method using a quartz/sapphire capillary tube as the synthesis reactor. The results were used for better design of materials with controlled structures and properties. This method can be generally used for synthesis of manganese oxides as well as for in situ characterization of other material syntheses using hydrothermal, sol-gel, and other methods. In addition, catalytic processes in liquid-solid, gas-solid, and solid-solid systems can also be studied in such an in situ way so that catalytic mechanisms can be better understood and catalyst synthesis and catalytic processes can be optimized. PMID:16594683

  18. In situ Synthesis of Mixed-Valent Manganese Oxide Nanocrystals: An In situ Synchrotron X-ray Diffraction Study

    International Nuclear Information System (INIS)

    Phase transformations of materials can be studied by in situ synchrotron X-ray diffraction. However, most reported in situ synchrotron XRD studies focus on solid state/gel systems by measuring phase/structure changes during application of pressure or heat. Phase transformations during material synthesis and their applications, especially in wet chemistry processes with different media, have not drawn much attention. Here, using manganese oxides as examples, we report the successful characterization of phase transformations in in situ hydrothermal synthesis conditions by the in situ synchrotron XRD method using a quartz/sapphire capillary tube as the synthesis reactor. The results were used for better design of materials with controlled structures and properties. This method can be generally used for synthesis of manganese oxides as well as for in situ characterization of other material syntheses using hydrothermal, sol-gel, and other methods. In addition, catalytic processes in liquid-solid, gas-solid, and solid-solid systems can also be studied in such an in situ way so that catalytic mechanisms can be better understood and catalyst synthesis and catalytic processes can be optimized

  19. Evidence for mass renormalization in LaNiO$"" sub 3_: an in situ soft x-ray photoemission study of epitaxial films

    CERN Document Server

    Horiba, K; Taguchi, M; Chainani, A; Kikkawa, A; Senba, Y; Ohashi, H; Shin, S

    2006-01-01

    We investigate the electronic structure of high-quality single-crystal LaNiO$_3$ (LNO) thin films using in situ photoemission spectroscopy (PES). The in situ high-resolution soft x-ray PES measurements on epitaxial thin films reveal the intrinsic electronic structure of LNO. We find a new sharp feature in the PES spectra crossing the Fermi level, which is derived from the correlated Ni 3$d$ $e_g$ electrons. This feature shows significant enhancement of spectral weight with decreasing temperature. From a detailed analysis of resistivity data, the enhancement of spectral weight is attributed to increasing electron correlations due to antiferromagnetic fluctuations.

  20. In Situ Near Infrared Spectroscopy for Analyte-Specific Monitoring of Glucose and Ammonium in Streptomyces coelicolor Fermentations

    DEFF Research Database (Denmark)

    Petersen, Nanna; Ödman, Peter

    2010-01-01

    There are many challenges associated with in situ collection of near infrared (NIR) spectra in a fermentation broth, particularly for highly aerated and agitated fermentations with filamentous organisms. In this study, antibiotic fermentation by the filamentous bacterium Streptomyces coelicolor was used as a model process. Partial least squares (PLS) regression models were calibrated for glucose and ammonium based on NIR spectra collected in situ. To ensure that the models were calibrated based on analyte-specific information, semisynthetic samples were used for model calibration in addition to data from standard batches. Thereby, part of the inherent correlation between the analytes could be eliminated. The set of semisynthetic samples were generated from fermentation broth from five separate fermentations to which different amounts of glucose, ammonium, and biomass were added. This method has previously been used off line but never before in situ. The use of semisynthetic samples along with validation on anindependent batch provided a critical and realistic evaluation of analyte-specific models based on in situ NIR spectroscopy. The prediction of glucose was highly satisfactory resulting in a RMSEP of 1.1 g/L. The prediction of ammonium based on NIR spectra collected in situ was not satisfactory. A comparison with models calibrated based on NIR spectra collected off line suggested that this is caused by signal attenuation in the optical fibers in the region above 2,000 nm; a region which contains important absorption bands for ammonium. For improved predictions of ammonium in situ, it is suggested to focus efforts on enhancing the signal in that particular region.

  1. 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

  2. In situ Measurements of Phytoplankton Fluorescence Using Low Cost Electronics

    Directory of Open Access Journals (Sweden)

    Dana L. Wright

    2013-06-01

    Full Text Available Chlorophyll a fluorometry has long been used as a method to study phytoplankton in the ocean. In situ fluorometry is used frequently in oceanography to provide depth-resolved estimates of phytoplankton biomass. However, the high price of commercially manufactured in situ fluorometers has made them unavailable to some individuals and institutions. Presented here is an investigation into building an in situ fluorometer using low cost electronics. The goal was to construct an easily reproducible in situ fluorometer from simple and widely available electronic components. The simplicity and modest cost of the sensor makes it valuable to students and professionals alike. Open source sharing of architecture and software will allow students to reconstruct and customize the sensor on a small budget. Research applications that require numerous in situ fluorometers or expendable fluorometers can also benefit from this study. The sensor costs US$150.00 and can be constructed with little to no previous experience. The sensor uses a blue LED to excite chlorophyll a and measures fluorescence using a silicon photodiode. The sensor is controlled by an Arduino microcontroller that also serves as a data logger.

  3. In situ measurements of phytoplankton fluorescence using low cost electronics.

    Science.gov (United States)

    Leeuw, Thomas; Boss, Emmanuel S; Wright, Dana L

    2013-01-01

    Chlorophyll a fluorometry has long been used as a method to study phytoplankton in the ocean. In situ fluorometry is used frequently in oceanography to provide depth-resolved estimates of phytoplankton biomass. However, the high price of commercially manufactured in situ fluorometers has made them unavailable to some individuals and institutions. Presented here is an investigation into building an in situ fluorometer using low cost electronics. The goal was to construct an easily reproducible in situ fluorometer from simple and widely available electronic components. The simplicity and modest cost of the sensor makes it valuable to students and professionals alike. Open source sharing of architecture and software will allow students to reconstruct and customize the sensor on a small budget. Research applications that require numerous in situ fluorometers or expendable fluorometers can also benefit from this study. The sensor costs US$150.00 and can be constructed with little to no previous experience. The sensor uses a blue LED to excite chlorophyll a and measures fluorescence using a silicon photodiode. The sensor is controlled by an Arduino microcontroller that also serves as a data logger. PMID:23783738

  4. In situ measurement of nitrate in deep-sea sediments with a microscale biosensor

    DEFF Research Database (Denmark)

    Marzocchi, Ugo; Revsbech, Niels Peter

    When a bacteria-based nitrate biosensor with tip diameter down to 20 µm was invented about 12 years ago it became possible to measure detailed nitrate profiles in marine sediments, but functional tip membranes in the sensors were difficult to make, and the sensors did not work at temperatures below about 8°C. Large resources are being spent on exploration of the deep sea using sensor-equipped benthic landers, and it would be of significant value to add nitrate to the array of chemical sensors for in situ use, but it is then necessary to construct more robust sensors that work at temperatures around 2°C. By isolation of psychrotrophic nitrate-reducing and N2O producing bacteria from arctic environments and by application of a new procedure for making microscale ion-permeable membranes we have now succeeded in making biosensors that function reproducibly at low temperatures. It has thus been possible to analyze detailed nitrate microprofiles with < 1 µM resolution in sediments off the Japanese coast at 1500 m water depth where the temperature was 2.5°C. Many of the profiles exhibited near-surface nitrate peaks due to nitrification, and subsequent nitrate consumption due to nitrate respiration in anoxic layers led to total depletion at 10-15 mm depth. A result from comparison of shallow (75 m) water sediment profiles recorded both in situ and on recovered sediment cores is that there was more variability in situ than in the laboratory, probably due to decreased animal activity during laboratory conditions. It is difficult to work strictly aseptically when producing the sensors, and there is thus a risk that the bacterial culture may be contaminated with N2O reducing bacteria that will make the sensor insensitive to nitrate. However, when used continuously at room temperature they usually work well for several days, and the shelf-life is up to several weeks if they are stored at 4-6°C.

  5. Innovative ground water and soil remediation: In situ air stripping using horizontal wells

    International Nuclear Information System (INIS)

    An innovative environmental restoration technology, in situ air stripping, has been demonstrated at the US Department of Energy's (DOE) Savannah River Site (SRS) in South Carolina. This process, using horizontal wells, is designed to concurrently remediate unsaturated-zone soils and ground water containing volatile organic compounds (VOCs). In situ technologies have the potential to substantially reduce costs and time required for remediation as well as improve effectiveness of remediation. Horizontal wells were selected to deliver and extract fluids from the subsurface because their geometry can maximize the efficiency of a remediation system and they have great potential for remediating contaminant sources under existing facilities. The in situ air stripping concept utilizes two parallel horizontal wells: one below the water table and one in the unsaturated zone. The deeper well is used as a delivery system for the air injection. VOCs are stripped from the ground water into the injected vapor phase and are removed from the subsurface by drawing a vacuum on the shallower well in the vadose zone. The first demonstration of this new technology was conducted for a period of twenty weeks. A vacuum was first drawn on the vadose zone well until a steady-state removal of VOCs was obtained. Air was then injected at three different rates and at two different temperatures. An extensive characterization program was conducted at the site and an extensive monitoring network was installed prior to initiation of the test. Significant quantities of VOCs have been removed from the subsurface (equivalent to an eleven-well 500 gpm pump-and-treat system at the same site). Concentrations of VOCs in the ground water have been significantly reduced in a number of the monitoring wells. In addition, the activity of indigenous microorganisms was increased as much as two orders of magnitude during the air injection

  6. Management Plan: Demonstration testing and evaluation of in situ soil heating

    International Nuclear Information System (INIS)

    In this project IITRI will demonstrate an in situ soil heating technology for the removal of hazardous organic contaminants present in the soil. In Situ heating will be accomplished by the application of 60 Hz AC power to the soil. The soil will be heated to a temperature of about 90 degree C. This technology is suited for the removal of those organic compounds which have a normal boiling point in the range of 100 degree to 210 degree C, or else for those which exhibit a pure component vapor pressure of at least 10 mm Hg in the 90 degree to 100 degree C temperature range. For example, perchloroethylene, dichlorobenzene, trichlorobenzene, etc. may be removed by in situ AC heating. It is planned to demonstrate the technology by heating approximately 400 tons of soil in the K-1070 Classified Burial Ground located at DOE's K-25 Site located in Oak Ridge, TN. It is estimated that the heating portion of the demonstration will take approximately 3 weeks at an average power input rate of 150 to 175 kill. IITRI expects to spend considerable time in the front end reviewing site characteristics, preparing detail design, developing Health and Safety Plans and other documents needed to obtain regulatory approval for the demonstration, arranging for site sampling, infrastructure development and document preparation. It is anticipated that site activities will begin in approximately 5 to 6 months. This contract was signed on September 30, 1993. IITRI started work on it in October 1993. It is planned to complete the demonstration and submit approved final reports by September 30, 1994. This project has 12 tasks and four major milestones. The major milestones and their planned completion dates are presented

  7. In Situ Sensors for the Chemical Industry- Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Tate, J.D.; Knittel, Trevor

    2006-06-30

    The project focused on analytical techniques that can be applied in situ. The innovative component of this project is the focus on achieving a significant breakthrough in two of the three primary Process Analytical (PA) fields. PA measurements can roughly be broken down into: ? Single component measurements, ? Multiple component measurements and ? Multiple component isomer analysis. This project targeted single component measurements and multiple component measurements with two basic technologies, and to move these measurements to the process, achieving many of the process control needs. During the project the following achievements were made: ? Development of a low cost Tunable Diode Laser (TDL) Analyzer system for measurement of 1) Oxygen in process and combustion applications, 2) part per million (ppm) H2O impurities in aggressive service, 3) ppm CO in large scale combustion systems. This product is now commercially available ? Development of a process pathlength enhanced (high sensitivity) Laser Based Analyzer for measurement of product impurities. This product is now commercially available. ? Development of signal processing methods to eliminate measurement errors in complex and changing backgrounds (critical to chemical industry measurements). This development is incorporated into 2 commercially available products. ? Development of signal processing methods to allow multi-component measurements in complex chemical streams. This development is incorporated into 2 commercially available products. ? Development of process interface designs to allow in-situ application of TDL technology in aggressive (corrosive, high temperature, high pressure) commonly found in chemical processes. This development is incorporated in the commercially available ASI TDL analyzer. ? Field proving of 3 laser-based analyzer systems in process control and combustion applications at Dow Chemical. Laser based analyzers have been available for >5yrs, however significant product price/performance issues have minimized their applicability in the chemical industry. In order to take advantage of the promise of this technology a number of technology advances were required, within price limits for market acceptance. This project significantly advanced the state of TDL technology for application in chemical industry applications. With these advances a commercially available product now exists that has already achieved market success and is installed in critical applications. The ability to make fast, sensitive and accurate measurements inside the chemical processes is now delivering improved process control, energy efficiency and emissions control within the U.S. Chemical Industry. Despite the success we enjoyed for the laser-based sensors, there were significant technical barriers for the solid-state sensors. With exception of a generic close-coupled extractive housing and electronics interface, there were significant issues with all of the solid-state sensor devices we sought to develop and test. Ultimately, these issues were roadblocks that prevented further development and testing. The fundamental limitations of available sensor materials that we identified, formulated and tested were overwhelming. This situation forced our team to cancel these portions of the project and focus our resources on laser-based sensor techniques. The barriers of material compatibility, sensitivity, speed of response, chemical interferences, etc. are surmountable in the field of solid-state sensors. Inability to address any single one of these attributes will prevent wide-implementation into this market. This situation is plainly evident by the lack of such devices in the online analyzer market (for petrochemicals).

  8. In situ photoemission study of LaNiO3 thin films grown by pulsed laser deposition

    International Nuclear Information System (INIS)

    We investigate the electronic structure of high-quality single-crystal LaNiO3(LNO) thin films using in situ photoemission spectroscopy (PES) in order to reveal the intrinsic electronic structure of LNO. The O 1s X-ray absorption (XAS) spectrum, which have much deeper probing depth than that of PES measurement, is in good agreement with previous studies on polycrystalline LNO surfaces. The in situ valence band PES spectrum shows well-resolved Ni 3d-derived t2g and eg features, while earlier X-ray photoemission studies on polycrystals showed a single band peak. The narrow eg-derived feature exhibits enhanced intensity compared to local density approximation band structure calculations. The results are consistent with a renormalization of electronic states at EF, in terms of the known enhanced effective mass

  9. Effect of Al alloys on selective laser melting behaviour and microstructure of in situ formed particle reinforced composites

    International Nuclear Information System (INIS)

    Highlights: ? Effect of Al alloy was examined on SLM facilitated in situ interaction with Fe2O3. ? The Al alloy influenced the SLM consolidation performance and the formed phases. ? In situ Al (alloy) composites were reinforced by ultrafine/nanoscale particles. ? The Al alloy affected the appearance of reinforced matrix. ? Enhanced solid solubility of matrix contributed to hardening. - Abstract: This work investigates the effects of various Al alloys (including Al, AlMg1SiCu, and AlSi10Mg), mixed with 15 wt% Fe2O3, on the selective laser melting (SLM) facilitated in situ reaction and formation of Al metal matrix composite (MMC) components. The results contribute to the development of medium/high strength Al composite parts which can be produced as complex net-shape products via the SLM process. Visual observation and computed tomography (CT) scanning reveal the best SLM consolidation performance and the lowest porosity for AlSi10Mg. SLM facilitated in situ reaction and subsequent rapid solidification introduce very fine particles (down to ?50–100 nm), reinforcing the microstructure of all Al (alloy) composites. The particles are Al–Fe intermetallics, Al oxides such as ?–Al2O3, plus Si crystals (alone or in combination) depending on the alloy composition. Ultrafine/nanoscale dendritic feature appears in the reinforced matrix of AlSi10Mg/15 wt%Fe2O3, in contrast with featureless matrix of Al/15 wt%Fe2O3. The in situ particle reinforced Al (alloy) composites are significantly harder than corresponding conventionally manufactured (e.g. casting) Al alloys without Fe2O3, due to superior microstructural characteristics such as featureless or very fine dendritic matrix, ultrafine/nanoscale particles, and also enhanced solid solubility of the SLM products.

  10. THIS COMMUNICATION IS CANCELLED (PAPER IS AVAILABLE). Analysis of in situ acoustical performance of concrete noise barriers

    OpenAIRE

    LECCESE, Francesco; Fantozzi, Fabio; Salvadori, Giacomo

    2012-01-01

    The need to enhance the people's mobility has produced a significant increase in the environmental pollution, including transportation noise. In order to reduce transportation noise it is possible to act directly on transport media or on the urban environment, by protecting sensitive receptors with techniques for noise reduction. The noise barriers are one of the most common examples of noise reduction devices. In this paper the authors show and discuss the results of an in situ analysis of t...

  11. Preparation of poly(ethylene terephthalate)/layered double hydroxide nanocomposites by in-situ polymerization and their thermal property

    OpenAIRE

    Q. Jiao; Cui, W; Zhao, Y; Li, H; Liu, H.; ZHOU, M

    2012-01-01

    Terephthalate (TA) intercalated layered double hydroxides (LDHs) were synthesized using hydroxides as raw materials, and poly(ethylene terephthalate) (PET)/LDH nanocomposites with different contents of TA intercalated LDHs were prepared by in-situ polymerization. The structure, morphology and thermal property of PET/LDH nanocomposites were investigated. The TA intercalated LDHs were partially exfoliated and well dispersed in PET matrix. The PET/LDH nanocomposites exhibit enhanced thermal stab...

  12. Two strain-hardening mechanisms in nanocrystalline austenitic steel: An in situ synchrotron X-ray diffraction study

    International Nuclear Information System (INIS)

    The mechanical behaviour of nanocrystalline austenitic steels with and without yttria particles was investigated using in situ synchrotron diffraction during tensile deformation. Two different strain-hardening regimes were found. The first regime can be assigned predominantly to a martensitic phase transformation, the second to deformation twinning in the fragmented retained austenite. The kinetics of martensitic phase transformation is remarkably enhanced in the nanocrystalline structure.

  13. Application of airborne survey and remote sensing technology to prospecting for in-situ leachable sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    The author briefly expounds the new ideas and methods of applying comprehensive airborne survey and remote sensing technology to the prospecting for in-situ leachable sandstone-type uranium deposits and the successful achievements in uranium exploration. Special emphasis is given to the integration and mutual complement of multi-source geoscience information, the application of computer data and digital image processing techniques, the extraction and enhancement of weak information that are the key chain for the success of the techniques

  14. Remote sensed and in situ constraints on processes affecting tropical tropospheric ozone

    Directory of Open Access Journals (Sweden)

    B. Sauvage

    2007-01-01

    Full Text Available We use a global chemical transport model (GEOS-Chem to evaluate the consistency of satellite measurements of lightning flashes and ozone precursors with in situ measurements of tropical tropospheric ozone. The measurements are tropospheric O3, NO2, and HCHO columns from the GOME satellite instrument, lightning flashes from the OTD and LIS satellite instruments, profiles of O3, CO, and relative humidity from the MOZAIC aircraft program, and profiles of O3 from the SHADOZ ozonesonde network. We interpret these multiple data sources with our model to better understand what controls tropical tropospheric ozone. Tropical tropospheric ozone is mainly affected by lightning NOx and convection in the upper troposphere and by surface emissions in the lower troposphere. Scaling the spatial distribution of lightning in the model to the observed flashes improves the simulation of O3 in the upper troposphere by 5–20 ppbv versus in situ observations and by 1–4 Dobson Units versus GOME retrievals of tropospheric O3 columns. A lightning source strength of 6±2 Tg N/yr best represents in situ observations from aircraft and ozonesonde. Tropospheric NO2 and HCHO columns from GOME are applied to provide top-down constraints on emission inventories of NOx (biomass burning and soils and VOCs (biomass burning. The top-down biomass burning inventory is larger than the bottom-up inventory by a factor of 2 for HCHO and alkenes, and by a factor of 2.6 for NOx over northern equatorial Africa. These emissions increase lower tropospheric O3 by 5–20 ppbv, improving the simulation versus aircraft observations, and by 4 Dobson Units versus GOME observations of tropospheric O3 columns. Emission factors in the a posteriori inventory are more consistent with a recent compilation from in situ measurements. The ozone simulation using two different dynamical schemes (GEOS-3 and GEOS-4 is evaluated versus observations; GEOS-4 better represents O3 observations by 5–15 ppbv, reflecting enhanced convective detrainment in the upper troposphere. Heterogeneous uptake of HNO3 on aerosols reduces simulated O3 by 5–7 ppbv, reducing a model bias versus in situ observations over and downwind of deserts. Exclusion of HO2 uptake on aerosols increases O3 by 5 ppbv in biomass burning regions, reducing a model bias versus MOZAIC aircraft measurements.

  15. Remote sensed and in situ constraints on processes affecting tropical tropospheric ozone

    Directory of Open Access Journals (Sweden)

    B. Sauvage

    2006-11-01

    Full Text Available We use a global chemical transport model (GEOS-Chem to evaluate the consistency of satellite measurements of lightning flashes and ozone precursors with in situ measurements of tropical tropospheric ozone. The measurements are tropospheric O3, NO2, and HCHO columns from the GOME satellite instrument, lightning flashes from the OTD and LIS instruments, profiles of O3, CO, and relative humidity from the MOZAIC aircraft program, and profiles of O3 from the SHADOZ ozonesonde network. We interpret these multiple data sources with our model to better understand what controls tropical tropospheric ozone. Tropical tropospheric ozone is mainly affected by lightning and convection in the upper troposphere and by surface emissions in the lower troposphere. Scaling the spatial distribution of lightning in the model to the observed flash counts improves the simulation of O3 in the upper troposphere by 5–20 ppbv versus in situ observations and by 1–4 Dobson Units versus GOME retrievals of tropospheric O3 columns. A lightning source strength of 5±2 Tg N/yr best represents in situ observations from aircraft and ozonesonde. Tropospheric NO2 and HCHO columns from GOME are applied to provide top-down constraints on emission inventories of NOx (biomass burning and soils and VOCs (biomass burning. The top-down biomass burning inventory is larger by a factor of 2 for HCHO and alkenes, and by 2.6 for NOx over northern equatorial Africa. These emissions increase lower tropospheric O3 by 5–20 ppbv, improving the simulation versus aircraft observations, and by 4 Dobson Units versus GOME observations of tropospheric O3 columns. Emission factors in the a posteriori inventory are more consistent with a recent compilation from in situ measurements. The ozone simulation using two different dynamical schemes (GEOS-3 and GEOS-4 is evaluated versus observations; GEOS-4 better represents O3 observations by 5–15 ppbv due to enhanced convective detrainment in the upper troposphere. Heterogeneous uptake of HNO3 on aerosols reduces simulated O3 by 5–7 ppbv, reducing a model bias versus in situ observations over and downwind of deserts. Exclusion of HO2 uptake on aerosols improves O3 by 5 ppbv in biomass burning regions.

  16. Dynamical properties of nano-structured catalysts for methane conversion: an in situ scattering study

    DEFF Research Database (Denmark)

    Kehres, Jan

    2011-01-01

    The reactivity of catalyst particles can be radically enhanced by decreasing their size down to the nanometer range. The nanostructure of a catalyst can have an enormous and positive influence on the reaction rate, for example strong structure sensitivity was observed for methane reforming and ammonia synthesis, and it is therefore crucial that catalysts preserve their nanostructures under operational conditions. Fundamental understanding of the relation between the catalytic activity and the morphology of the nanoparticle, their crystallinity and crystallite size, is required to improve the catalysts and assess the optimum conditions of operation. A powerful and suitable technique to resolve these relations is simultaneous small and wide angle X-ray scattering coupled with mass spectroscopy measurements, performed in situ at conditions comparable to large scale processes. A new heater setup for an in situ cell, accommodated in a laboratory SAXS/WAXS camera, has been developed and a sample gas system has beendesigned and installed. A mass spectrometer has been implemented to monitor the chemical reactions during the in situ experiments. The heater permits experiments in a temperature range from 298 - 1073 K. The heater performance was tested and it was shown that no temperature calibration is needed. The applicability of the new setup, to study nanostructured materials, was successfully demonstrated using anatase TiO2 nanorods. Heating experiments on the nanorods were performed in a temperature range from 298 - 1023 K. Correlated crystallite and particle growth due to sintering were observed after the decomposition of the surfactant. Furthermore transformations from rod to spherical particle shape were observed. In situ reduction experiments of a Ni/MgAl2O4 catalyst were performed. The Ni/NiO particles in a fresh catalyst sample showed a Ni/NiO core shell structure. The Ni lattice parameter decreased during the reduction due to the release of stress between the Ni core and the NiO shell. Ni particles sintered during heating in hydrogen after the reduction of the NiO shell. Dry reforming experiments were performed over a Ru/MgAl2O4. The catalyst showed a high sintering stability and no catalyst deactivation was observed. The results presented in this thesis emphasize the advantage of the simultaneous SAXS/W AXS laboratory setup to study nanostructured materials and catalysts in situ.

  17. In-Situ Electrochemical Transmission Electron Microscopy for Battery Research

    Energy Technology Data Exchange (ETDEWEB)

    Mehdi, Beata L [Pacific Northwest National Laboratory (PNNL); Gu, Meng [Pacific Northwest National Laboratory (PNNL); Parent, Lucas [Pacific Northwest National Laboratory (PNNL); Xu, WU [Pacific Northwest National Laboratory (PNNL); Nasybulin, Eduard [Pacific Northwest National Laboratory (PNNL); Chen, Xilin [Pacific Northwest National Laboratory (PNNL); Unocic, Raymond R [ORNL; Xu, Pinghong [University of California, Davis; Welch, David [Pacific Northwest National Laboratory (PNNL); Abellan, Patricia [Pacific Northwest National Laboratory (PNNL); Zhang, Ji-Guang [Pacific Northwest National Laboratory (PNNL); Liu, Jun [Pacific Northwest National Laboratory (PNNL); Wang, Chongmin [Pacific Northwest National Laboratory (PNNL); Arslan, Ilke [Pacific Northwest National Laboratory (PNNL); Evans, James E [Pacific Northwest National Laboratory (PNNL); Browning, Nigel [Pacific Northwest National Laboratory (PNNL)

    2014-01-01

    The recent development of in-situ liquid stages for (scanning) transmission electron microscopes now makes it possible for us to study the details of electrochemical processes under operando conditions. As electrochemical processes are complex, care must be taken to calibrate the system before any in-situ/operando observations. In addition, as the electron beam can cause effects that look similar to electrochemical processes at the electrolyte/electrode interface, an understanding of the role of the electron beam in modifying the operando observations must also be understood. In this paper we describe the design, assembly, and operation of an in-situ electrochemical cell, paying particular attention to the method for controlling and quantifying the experimental parameters. The use of this system is then demonstrated for the lithiation/delithiation of silicon nanowires.

  18. In Situ Electrochemical Transmission Electron Microscopy for Battery Research

    Energy Technology Data Exchange (ETDEWEB)

    Mehdi, Beata L.; Gu, Meng; Parent, Lucas R.; Xu, Wu; Nasybulin, Eduard N.; Chen, Xilin; Unocic, Raymond R.; Xu, Pinghong; Welch, David A.; Abellan, Patricia; Zhang, Jiguang; Liu, Jun; Wang, Chong M.; Arslan, Ilke; Evans, James E.; Browning, Nigel D.

    2014-04-01

    The recent development of in situ liquid stages for (scanning) transmission electron microscopes now makes it possible for us to study the details of electrochemical processes under operando conditions. As electrochemical processes are complex, care must be taken to calibrate the system before any in situ/operando observations. In addition, as the electron beam can cause effects that look similar to electrochemical processes at the electrolyte/electrode interface, an understanding of the role of the electron beam in modifying the operando observations must also be understood. In this paper we describe the design, assembly, and operation of an in situ electrochemical cell, paying particular attention to the method for controlling and quantifying the experimental parameters. The use of this system is then demonstrated for the lithiation/delithiation of silicon nanowires.

  19. In-situ nitrite analysis in high level waste tanks

    International Nuclear Information System (INIS)

    The Savannah River Site produces special nuclear materials used in the defense of the United States. Most of the processes at SRS are primarily chemical separations and purifications. In-situ chemical analyses help improve the safety, efficiency and quality of these operations. One area where in situ fiberoptic spectroscopy can have a great impact is the management of high level radioactive waste. High level radioactive waste at SRS is stored in more than 50 large waste tanks. The waste exists as a slurry of nitrate salts and metal hydroxides at pH's higher than 10. Sodium Nitrite is added to the tanks as a corrosion inhibitor. In-situ fiberoptic probes are being developed to measure the nitrate, nitrite and hydroxide concentrations in both liquid and solid fractions. Nitrite levels can be measured between 0.01M and 1M in a 1mm pathlength optical cell

  20. In situ testing program at the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    This paper discusses the In Situ Testing program at the WIPP site which is providing answers to questions about the efficacy of storing radioactive wastes in the geologic medium of natural salt deposits. The In Situ Testing program is aimed at the total repository system, emphasizing the concepts of waste confinement and isolation. The challenge faced by the In Situ Testing program is to investigate the issues of radioactive waste storage in a salt repository environment well enough to provide dependable predictions of the long-term effects of waste disposal. Design methods, test procedures, and data results are carefully documented to ensure their availability for review by interested organizations and future repository designers

  1. Detector calibration for in-situ gamma ray spectrometry

    CERN Document Server

    Balea, G

    2002-01-01

    The power in the technique of in-situ spectrometry lies in the fact that a detector placed on ground measures gamma radiation from sources situated over an area of several hundred square meters. The 'field of view' for the detector would be larger for high energy radiation sources and for sources closer to the soil surface. In contrast, a soil sample would represent an area of a few tens of hundreds of square centimeters. In practice, an effective characterization of a site would involve in-situ gamma ray spectrometry in conjunction with soil sampling. As part of an overall program, in-situ gamma ray spectrometry provides a means to assess the degree of contamination in areas during the course of operations in the field, thus guiding the investigator on where to collect samples. It can also substantially reduce the number of samples need to be collected and subsequently analyzed. (author)

  2. Design, fabrication, and applications of in situ fluid cell TEM.

    Science.gov (United States)

    Li, Dongsheng; Nielsen, Michael H; De Yoreo, James J

    2013-01-01

    In situ fluid cell TEM is a powerful new tool for understanding dynamic processes during liquid phase chemical reactions, including mineral formation. This technique, which operates in the high vacuum of a TEM chamber, provides information on crystal structure, phase, morphology, size, aggregation/segregation, and crystal growth mechanisms in real time. In situ TEM records both crystal structure and morphology at spatial resolutions down to the atomic level with high temporal resolution of up to 10(-6)s per image, giving it distinct advantages over other in situ techniques such as optical microscopy, AFM, or X-ray scattering or diffraction. This chapter addresses the design, fabrication, and assembly of TEM fluid cells and applications of fluid cell TEM to understanding mechanisms of mineralization. PMID:24188766

  3. Applications of in situ gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Gamma-ray spectrometric methods using high-resolution Ge(Li) and high purity Ge detectors have been used to quantify the concentrations and external exposure rates of radionuclides in the soil. These in situ methods have been used to study radionuclide deposition around nuclear power stations, the distribution of radionuclides at the Nevada Test Site, biogeochemical cycling of radionuclides, and the fate and impact of fallout radionuclides. Portable gamma-ray spectrometer systems used for various kinds of in situ field measurements include: large-volume coaxial Ge(Li) detectors for terrestrial gamma-ray surveys at several sites including preoperational nuclear power plants and for real-time measurements of nuclear reactor plume isotopic exposure rates; and planar, high purity Ge detectors for mapping 241Am and 239Pu soil concentrations, particularly at the Nevada Test Site. These applications are discussed along with a brief description of the methodology and techniques associated with in situ gamma-ray spectrometry

  4. Development of portable HPGe spectrometer for in situ measurements

    Directory of Open Access Journals (Sweden)

    Kail Artjoms

    2015-01-01

    Full Text Available In situ applications require a very high level of portability of high-resolution spectrometric equipment. Usage of HPGe detectors for radioactivity measurements in the environment or for nuclear safeguard applications, to combat illicit trafficking of nuclear materials or uranium and plutonium monitoring in nuclear wastes, has become a norm in the recent years. Portable HPGe-based radionuclide spectrometer with electrical cooling has lately appeared on the market for in situ applications. At the same time deterioration of energy resolution associated with vibrations produced by cryocooler or high weight of the instrument, short time of autonomous operation and high price of these spectrometers are limiting their usage in many cases. In this paper we present development results of ultra compact hand held all-in-one spectrometer for in situ measurements based on HPGe detector cooled by liquid nitrogen without listing the above disadvantages.

  5. Applications of in situ hybridization to plant-improvement

    International Nuclear Information System (INIS)

    In situ hybridization is a powerful method for characteristic alien addition and substitution lines. RFLP analysis can identify the presence of a particular individual chromosome, but whether they are as a pair or as a single chromosome cannot be determined. In situ hybridization has become established as an essential method in cell and molecular biology. It is able to link DNA sequences with their organization and physical position. The rate of technology-development in the field of in situ hybridization has been rapid: radioactive probes are now rarely used, while labeling methods, fluorochromes, chromosomes and tissue-preparation methods, microscope and imaging technology have all useful in functional genomics and localization of transgenes on the chromosomes. (author)

  6. Robot-Assisted Antegrade In-Situ Fenestrated Stent Grafting

    International Nuclear Information System (INIS)

    To determine the technical feasibility of a novel approach of in-situ fenestration of aortic stent grafts by using a remotely controlled robotic steerable catheter system in the porcine model. A 65-kg pig underwent robot-assisted bilateral antegrade in-situ renal fenestration of an abdominal aortic stent graft with subsequent successful deployment of a bare metal stent into the right renal artery. A 16-mm iliac extension covered stent served as the porcine aortic endograft. Under fluoroscopic guidance, the graft was punctured with a 20-G customized diathermy needle that was introduced and kept in place by the robotic arm. The needle was exchanged for a 4 x 20 mm cutting balloon before successful deployment of the renal stent. Robot-assisted antegrade in-situ fenestration is technically feasible in a large mammalian model. The robotic system enables precise manipulation, stable positioning, and minimum instrumentation of the aorta and its branches while minimizing radiation exposure.

  7. Freshening in the South China Sea during 2012 Revealed By Aquarius and in-Situ Data

    Science.gov (United States)

    Zeng, L.; Liu, W. T.; Xue, H.; Wang, D.; Xing, T.

    2014-12-01

    Newly available sea surface salinity (SSS) data from the Aquarius together with in-situ hydrographic data are used to explore the spatial and temporal characteristics of SSS in the South China Sea (SCS). An evaluation of daily Aquarius data indicates that there exists a negative bias of 0.45 psu for the version 3.0 dataset. The root-mean-square differences (RMSD) for daily Aquarius SSS is about 0.53 after correcting the systematic bias, and those for weekly and monthly Aquarius SSSs are 0.45 and 0.29 psu, respectively. Nevertheless, the Aquarius SSS shows a reliable freshening in 2012, especially in the northern SCS, as the in-situ data does. The northern SCS freshening was around 0.40 psu, which is larger than Aquarius uncertainty indicated by the monthly RMSD. This freshening was caused by a combined effect of local freshwater flux and Kuroshio intrusion. By comparing with 2011, we attribute reduced Kuroshio intrusion as the cause for the freshening over the northern SCS in 2012. In the region near the Mekong River mouth, the river discharge during flood season plays an important role.

  8. In situ SERS spectroelectrochemical analysis of antioxidants deposited on copper substrates: What is the effect of applied potential on sorption behavior?

    Science.gov (United States)

    Dendisova-Vyskovska, Marcela; Broncova, Gabriela; Clupek, Martin; Prokopec, Vadym; Matejka, Pavel

    2012-12-01

    The detection of p-coumaric acid and ferulic acid using a combined in situ electrochemical and surface-enhanced Raman scattering spectroscopic technique in specially made electrode cell is described. New in situ spectroelectrochemical cell was designed as the three-electrode arrangement connected via positioning device to fiber-optic probe of Raman spectrometer Dimension P2 (excitation wavelength 785 nm). In situ SERS spectra of p-coumaric acid and ferulic acid were recorded at varying applied negative potentials to copper substrates. The spectral intensities and shapes of bands as well as spatial orientation of molecules on the surface depend significantly on varying values of the applied electrode potential. The change of electrode potential influences analyte adsorption/desorption behavior on the surface of copper substrates, affecting the reversibility of the whole process and overall spectral enhancement level. Principal component analysis is used to distinguish several stages of spectral variations on potential changes.

  9. Experimental investigation of in situ cleanable HEPA filter

    International Nuclear Information System (INIS)

    The Westinghouse Savannah River Company located at the Savannah River Site (SRS) in Aiken, South Carolina is currently testing the feasibility of developing an in situ cleanable high efficiency particulate air (HEPA) filter system. Sintered metal filters are being tested for regenerability or cleanability in simulated conditions found in a high level waste (HLW) tank ventilation system. The filters are being challenged using materials found in HLW tanks. HLW simulated salt, HLW simulated sludge and South Carolina road dust. Various cleaning solutions have been used to clean the filters in situ. The tanks are equipped with a ventilation system to maintain the tank contents at negative pressure to prevent the release of radioactive material to the environment. This system is equipped with conventional disposable glass-fiber HEPA filter cartridges. Removal and disposal of these filters is not only costly, but subjects site personnel to radiation exposure and possible contamination. A test apparatus was designed to simulate the ventilation system of a HLW tank with an in situ cleaning system. Test results indicate that the Mott sintered metal HEPA filter is suitable as an in situ cleanable or regenerable HEPA filter. Data indicates that high humidity or water did not effect the filter performance and the sintered metal HEPA filter was easily cleaned numerous times back to new filter performance by an in situ spray system. The test apparatus allows the cleaning of the soiled HEPA filters to be accomplished without removing the filters from process. This innovative system would eliminate personnel radiation exposure associated with removal of contaminated filters and the high costs of filter replacement and disposal. The results of these investigations indicate that an in situ cleanable HEPA filter system for radioactive and commercial use could be developed and manufactured

  10. Particle size alterations of feedstuffs during in situ NDF incubation

    DEFF Research Database (Denmark)

    Krämer, Monika; NØrgaard, P.

    2013-01-01

    Particle size alterations during neutral detergent fiber (NDF) determination and in situ rumen incubation were analyzed by dry sieving and image analysis. The in situ procedure for estimation of NDF degradation parameters and indigestible NDF concentration used for feed evaluation was thereby evaluated in terms of particle size for a broad range of feedstuffs which typically serve as NDF sources in dairy cow rations. Early and late cut grass silages, corn silage, alfalfa silage, rapeseed meal and dried distillers grains were examined. Treatments were I) drying and grinding of forage samples and grinding of concentrates, II) neutral detergent soluble (NDS) extraction, III) machine-washing and NDS extraction, IV) 24 h rumen incubation, machine-washing and NDS extraction, and V) 288 h rumen incubation, machine-washing and NDS extraction. Degradation profiles for potentially degradable NDF were determined and image analysis was used to estimate particle size profiles and thereby the risk for particle loss. Particle dimensions changed during NDF determination and in situ rumen incubation and variations depended on feedstuff and treatment. Late cut grass silage varied most in particle area among feedstuffs with a decrease of 74 % between 24 h and 288 h in situ rumen incubation. Together with the highest mass proportion (20 %) of particles in the critical zone for escape (smaller than 0.005 mm2 in area) for late cut grass silage after 288 h in situ rumen incubation, this imposes a risk for particle loss during incubation in the bags. Particle area decreased linearly with increasing incubation time. Particle loss during in situ rumen incubation could therefore not be excluded and was likely to vary among feedstuffs.

  11. Measuring in situ vertical hydraulic conductivity in tidal environments

    Science.gov (United States)

    Wang, Xuejing; Li, Hailong; Yang, Jinzhi; Wan, Li; Wang, Xusheng; Jiang, Xiaowei; Guo, Huaming

    2014-08-01

    The hydraulic conductivity of intertidal sediments plays an important role in quantifying seawater-groundwater interactions. However, its accurate and economical in situ evaluation is difficult since available in situ methods do not apply in intertidal zones due to periodic tidal fluctuations. Here a new apparatus is presented for measuring the sediments' vertical hydraulic conductivity in tidal environments and a simple, finite-difference data analysis method is proposed to estimate this key parameter. The new apparatus is easy to operate, and is able to measure in situ vertical hydraulic conductivity ranging from 10-7 m/s to 10-2 m/s in tidal environments within one hour. A posteriori error of the finite-difference approximation method is estimated to have the same magnitude order as the square of the nondimensionalized observation time interval K?t/(LV) (here ?t is the observation time interval, Rd is the diameter ratio of the falling-head water-container standpipe to the undisturbed in situ sediment sample, K is the vertical hydraulic conductivity, and LV is the sample length), which is usually a very small number. The new apparatus and finite-difference method were verified by numerical simulations and many in situ experiments in several coastal case study sites of Bohai Sea, PR China. The finite-difference method has adequate accuracy in estimating the hydraulic conductivity compared with the traditional least-squares fitting method. The relative error between the estimates by the two methods is less than 9.41% and averages 1.22% for all experiments. The new apparatus and simple finite-difference method are recommended for in situ experiment that have many advantages such as economy, efficiency, reliability, and simplicity.

  12. In-situ Rock Spalling Strength near Excavation Boundaries

    Science.gov (United States)

    Cai, M.; Kaiser, P. K.

    2014-03-01

    It is widely accepted that the in-situ strength of massive rocks is approximately 0.4 ± 0.1 UCS, where UCS is the uniaxial compressive strength obtained from unconfined tests using diamond drilling core samples with a diameter around 50 mm. In addition, it has been suggested that the in-situ rock spalling strength, i.e., the strength of the wall of an excavation when spalling initiates, can be set to the crack initiation stress determined from laboratory tests or field microseismic monitoring. These findings were supported by back-analysis of case histories where failure had been carefully documented, using either Kirsch's solution (with approximated circular tunnel geometry and hence ? max = 3? 1 -? 3) or simplified numerical stress modeling (with a smooth tunnel wall boundary) to approximate the maximum tangential stress ? max at the excavation boundary. The ratio of ? max /UCS is related to the observed depth of failure and failure initiation occurs when ? max is roughly equal to 0.4 ± 0.1 UCS. In this article, it is suggested that these approaches ignore one of the most important factors, the irregularity of the excavation boundary, when interpreting the in-situ rock strength. It is demonstrated that the "actual" in-situ spalling strength of massive rocks is not equal to 0.4 ± 0.1 UCS, but can be as high as 0.8 ± 0.05 UCS when surface irregularities are considered. It is demonstrated using the Mine-by tunnel notch breakout example that when the realistic "as-built" excavation boundary condition is honored, the "actual" in-situ rock strength, given by 0.8 UCS, can be applied to simulate progressive brittle rock failure process satisfactorily. The interpreted, reduced in-situ rock strength of 0.4 ± 0.1 UCS without considering geometry irregularity is therefore only an "apparent" rock strength.

  13. Pilot-scale in situ bioremediation of HMX and RDX in soil pore water in Hawaii.

    Science.gov (United States)

    Payne, Zachary M; Lamichhane, Krishna M; Babcock, Roger W; Turnbull, Stephen J

    2013-10-01

    A nine-month in situ bioremediation study was conducted in Makua Military Reservation (MMR) in Oahu, Hawaii (USA) to evaluate the potential of molasses to enhance biodegradation of royal demolition explosive (RDX) and high-melting explosive (HMX) contaminated soil below the root zone. MMR has been in operation since the 1940's resulting in subsurface contamination that in some locations exceeds USEPA preliminary remediation goals for these chemicals. A molasses-water mixture (1?:?40 dilution) was applied to a treatment plot and clean water was applied to a control plot via seven flood irrigation events. Pore water samples were collected from 12 lysimeters installed at different depths in 3 boreholes in each test plot. The difference in mean concentrations of RDX in pore water samples from the two test plots was very highly significant (p irrigation. Use of the bioremediation method described herein could allow the sustainable use of live fire training ranges by enhancing biodegradation of explosives in situ and preventing them from migrating to through the vadose zone to underlying ground water and off-site. PMID:24061783

  14. Tests of In-Situ Formation Scenarios for Compact Multiplanet Systems

    CERN Document Server

    Schlaufmam, Kevin C

    2014-01-01

    Kepler has identified over 600 multiplanet systems, many of which have several planets with orbital distances smaller than that of Mercury -- quite different from the Solar System. Because these systems may be difficult to explain in the paradigm of core accretion and disk migration, it has been suggested that they formed in situ within protoplanetary disks with high solid surface densities. The strong connection between giant planet occurrence and stellar metallicity is thought to be linked to enhanced solid surface densities in disks around metal-rich stars, so the presence of a giant planet can be a detectable sign of planet formation in a high solid surface density disk. I formulate quantitative predictions for the frequency of long-period giant planets in these in situ models of planet formation by translating the proposed increase in disk mass into an equivalent metallicity enhancement. I rederive the scaling of giant planet occurrence with metallicity as P_gp = 0.05_{-0.02}^{+0.02} x 10^{(2.1 +/- 0.4) ...

  15. Alkaline membrane fuel cells with in-situ cross-linked ionomers

    Energy Technology Data Exchange (ETDEWEB)

    Leng, YJ; Wang, LZ; Hickner, MA; Wang, CY

    2015-01-10

    Improving cell performance and durability through both new materials and membrane electrode processing optimization is needed for the commercialization of alkaline membrane fuel cell (AMFC) technologies. In this work, we adopted an in-situ cross-linking strategy of an anion-conducting block copolymer to prepare durable ionomers for use in alkaline membrane fuel cells (AMFCs). Our goal was to use new ionomers and binders with an aim at improving long-term stability of AMFCs, especially at high operation temperatures. At 80 degrees C, AMFCs with in-situ cross-linked ionomers showed promising stability with an operating life time of more than 350 hours at 100 mA/cm(2). We found that the optimized electrode fabrication process and operating conditions can significantly improve the durability performance of AMFCs. For example, a suitable electrode binder in addition to the ion-conducting ionomer can greatly enhance the durability performance of AMFCs. Operating fuel cells under a cathode over-humification condition can also enhance the long-term stability of AMFCs. (C) 2014 Elsevier Ltd. All rights reserved.

  16. In situ study of the magnetoelectrolysis phenomenon during copper electrodeposition using time domain NMR relaxometry.

    Science.gov (United States)

    Gomes, Bruna Ferreira; Nunes, Luiza Maria Silva; Lobo, Carlos Manuel Silva; Cabeça, Luís Fernando; Colnago, Luiz Alberto

    2014-10-01

    Although the effect of magnetic field (B) on electrochemical reactions (magnetoelectrolysis phenomenon) has been long known, it has not been considered in electrochemical reactions analyzed in situ by magnetic resonance methods, such as nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and magnetic resonance imaging (MRI), which are intrinsically performed in the presence of B. In this report, the effect of B on the copper electrodeposition reaction, measured by a low-field (0.23 T) NMR spectrometer, was demonstrated. As expected, an enhancement in the reaction rate in comparison to the ex situ electrodeposition reaction was observed. Such enhancement was not dependent on electrodes/magnetic field orientations. Parallel and perpendicular orientations showed similar electrodeposition rates, which is explained by the cyclotron flows generated by distortions in electric and magnetic field lines near the electrode and the electrode edge. Therefore, NMR spectroscopy is not a passive analytical method, as assumed in preceding in situ spectroelectrochemical studies. Although the magnetoelectrolysis phenomenon demonstrated in this report used a paramagnetic ion, it can also be observed for diamagnetic species, since the magnetoelectrolysis phenomenon is independent of the nature of the species. Consequently, similar convection effects may occur in other electrochemical nuclear magnetic resonance (EC-NMR) experiments, such as the electrochemical reaction of organic molecules, as well as in electrocatalysis/fuel cells, lithium-ion batteries, and experiments that use electrochemical electron paramagnetic resonance (EC-EPR) and electrochemical magnetic resonance imaging (EC-MRI). PMID:25162751

  17. Comparison of in-situ and ex-situ catalytic pyrolysis in a micro-reactor system.

    Science.gov (United States)

    Wang, Kaige; Johnston, Patrick A; Brown, Robert C

    2014-12-01

    In this study, we compared ex-situ catalytic pyrolysis (CP) and in-situ CP of hybrid poplar in a micro-reactor system. When both pyrolysis and catalysis were performed at 700 °C, the carbon yield of olefins was greater for ex-situ CP than for in-situ CP (17.4% vs. 5.4%). On the other hand, in-situ CP produced more aromatic hydrocarbons than ex-situ CP (26.1% vs. 18.9%). The remarkably high yield of olefins from ex-situ CP indicates the potential of exploiting the process to preferentially produce olefins as a primary product from biomass, with aromatics being the secondary products. The carbon yield of carbonaceous residues from ex-situ CP was 18.6% compared to 31.3% for in-situ CP. Substantial carbon was deposited as char during ex-situ CP, which could be easily recovered as by-product, simplifying catalyst regeneration. The effects of catalyst loading, pyrolysis temperature and catalysis temperature on product distributions for ex-situ CP were also investigated. Our results showed that catalyst temperature strongly affected product distribution. While high catalyst temperature enhanced both olefin and aromatic production, yield of olefin increased to a greater extent than did aromatics. Neither pyrolysis temperature nor catalyst loadings had significant effect on product distribution for ex-situ CP. PMID:25299488

  18. Mechanism for high critical current density in in situ MgB2 wire with large area-reduction ratio

    Science.gov (United States)

    Kodama, Motomune; Ichiki, Yota; Tanaka, Kazuhide; Okamoto, Kazutaka; Yamamoto, Akiyasu; Shimoyama, Jun-ichi

    2014-03-01

    A comparative study of in situ MgB2 wire and MgB2 bulk was carried out to clarify the mechanism for the high critical current density, Jc, in the practical in situ MgB2 wires. The in situ MgB2 wire was manufactured with an area-reduction ratio of 99.93%, which was one of the highest values in MgB2 superconducting wires previously reported. The electrical connectivity, K, and the flux pinning strength, Fp, which are important factors in explaining the behavior of Jc, could be determined in the same manner as those for the bulk sample; K was well understood with the three-dimensional percolation model, and Fp was effectively explained by the electron scattering mechanism by grain boundaries. On the other hand, the area-reduction process dramatically enhanced the value of K, leading to an increase in the value of Jc. The respective values of K and Jc(20 K, ˜0 T) reached 0.24-0.34 and 6.0 × 103-8.4 × 103 A mm-2, which were twice or three times higher than those of typical in situ bulks. This is because the plastic deformation of magnesium particles increased the packing factor of raw powders through a repetitive drawing process.

  19. In situ remediation integrated program: Success through teamwork

    International Nuclear Information System (INIS)

    The In Situ Remediation Integrated Program (ISR IP), managed under the US Department of Energy's (DOE) Office of Technology Development, focuses research and development efforts on the in-place treatment of contaminated environmental media, such as soil and groundwater, and the containment of contaminants to prevent the contaminants from spreading through the environment. As described here, specific ISR IP projects are advancing the application of in situ technologies to the demonstration point, providing developed technologies to customers within DOE. The ISR IP has also taken a lead role in assessing and supporting innovative technologies that may have application to DOE

  20. PPLA-cellulose nanocrystals nanocomposite prepared by in situ polymerization

    International Nuclear Information System (INIS)

    This work reports the preparation and and characterization of a PLLA-cellulose nanocrystals nanocomposite obtained by in situ polymerization. The nanocomposite was prepared by ring opening polymerization of the lactide dimer in the presence of cellulose nanocrystals (CNCs) and the as-obtained materials was characterized using FTIR, DSC, XRD and TGA measurements. The incorporation of cellulose nanocrystals in PLLA using this method improved the thermal stability and increased the crystallinity of PLLA. These results indicate that the incorporation of CNCs by in situ polymerization improve thermal properties and has potential to improve also mechanical properties of this biodegradable polymer. (author)

  1. Continued Development of in Situ Geochronology for Planetary Missions

    Science.gov (United States)

    Devismes, D.; Cohen, B. A.

    2015-01-01

    The instrument 'Potassium (K) Argon Laser Experiment' (KArLE) is developed and designed for in situ absolute dating of rocks on planetary surfaces. It is based on the K-Ar dating method and uses the Laser Induced Breakdown Spectroscopy - Laser Ablation - Quadrupole Mass Spectrometry (LIBSLA- QMS) technique. We use a dedicated interface to combine two instruments similar to SAM of Mars Science Laboratory (for the QMS) and ChemCam (for the LA and LIBS). The prototype has demonstrated that KArLE is a suitable and promising instrument for in situ absolute dating.

  2. In-situ studies with photons, neutrons and electrons scattering

    CERN Document Server

    Kannengiesser, Thomas; Komizo, Yu-Ichi; Ramirez, Antonio J

    2010-01-01

    In-situ scattering and diffraction measurements using synchrotron and neutron beam lines have become a viable tool to look at the non-equilibrium processing of advanced materials. This volume presents the subject from the theoretical and experimental standpoint, in order to provide a closer insight into the different synchrotron and neutron diffraction techniques as well as innovative microscopy techniques. It addresses the following items: Phase detection and quantification; In-situ welding experiments; Stress/strain build-up; Model development and Simulation; and, Analysis tools and programm

  3. Contribution of fluorescence in situ hybridization to biological dosimetry

    International Nuclear Information System (INIS)

    Fluorescence in situ hybridization with composite whole chromosome specific DNA probes for human chromosomes 2, 4 and 12 an ?-satellite centromeric DNA probe labelled with biotin were used to measure symmetrical and terminal translocations (dose rate 0.5 Gy/min) and dicentrics (0.1 Gy/min) induced in vitro by 60Co ?-irradiation (0-5 Gy). The suitability of fluorescence in situ hybridization (F.I.S.H.) technique for dicentrics detection is compared with the conventional technique. Dose-response curves for ?-rays (60Co) for two dose rates are shown (dicentrics and translocations). (authors). 10 refs., 2 figs

  4. PPLA-cellulose nanocrystals nanocomposite prepared by in situ polymerization

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This work reports the preparation and and characterization of a PLLA-cellulose nanocrystals nanocomposite obtained by in situ polymerization. The nanocomposite was prepared by ring opening polymerization of the lactide dimer in the presence of cellulose nanocrystals (CNCs) and the as-obtained materials was characterized using FTIR, DSC, XRD and TGA measurements. The incorporation of cellulose nanocrystals in PLLA using this method improved the thermal stability and increased the crystallinity of PLLA. These results indicate that the incorporation of CNCs by in situ polymerization improve thermal properties and has potential to improve also mechanical properties of this biodegradable polymer. (author)

  5. Comparison of open pit and in situ leach economics

    International Nuclear Information System (INIS)

    The intention of this brief study has been to illustrate the kinds of deposits which may be exploited by in situ leaching and show how analysis of the significant process variables can point to profitable areas of research and development. Hopefully, such a process can be instrumental in bringing in situ leach technology up to the level of understanding and dependability of today's conventional processes. If these assumptions are reasonably verified, presently marginal deposits will move into the economic category. 4 figures, 9 tables

  6. Adapting uranium in situ mining technology for new commercial operations

    International Nuclear Information System (INIS)

    The vast majority of uranium produced commercially in the United States by in-situ leach methods has come from the South Texas deposits. The technology is applicable to deposits in other parts of the United States with some modifications. This paper reviews the technology variations and operating procedures used to mine other deposits and compares these with South Texas operations. Suggestions are made as to how improvements in technology and operating procedures will make uranium in-situ mining operations more competitive in today's market. (author). 12 figs, 8 tabs

  7. In-situ birth of MSCs multicellular spheroids in poly(l-glutamic acid)/chitosan scaffold for hyaline-like cartilage regeneration.

    Science.gov (United States)

    Zhang, Kunxi; Yan, Shifeng; Li, Guifei; Cui, Lei; Yin, Jingbo

    2015-12-01

    The success of mesenchymal stem cells (MSCs) based articular cartilage tissue engineering is limited by the presence of fibrous tissue in generated cartilage, which is associated with the current scaffold strategy that promotes cellular adhesion and spreading. Here we design a non-fouling scaffold based on amide bonded poly(l-glutamic acid) (PLGA) and chitosan (CS) to drive adipose stem cells (ASCs) to aggregate to form multicellular spheroids with diameter of 80-110 ?m in-situ. To illustrate the advantage of the present scaffolds, a cellular adhesive scaffold based on the same amide bonded PLGA and CS was created through a combination of air-drying and freeze-drying to limit the hydration effect while also achieving porous structure. Compared to ASCs spreading along the surface of pores within scaffold, the dense mass of aggregated ASCs in PLGA/CS scaffold exhibited enhanced chondrogenic differentiation capacity, as determined by up-regulated GAGs and COL II expression, and greatly decreased COL I deposition during in vitro chondrogenesis. Furthermore, after 12 weeks of implantation, neo-cartilages generated by ASCs adhered on scaffold significantly presented fibrous matrix which was characterized by high levels of COL I deposition. However, neo-cartilage at 12 weeks post-implantation generated by PLGA/CS scaffold carrying ASC spheroids possessed similar high level of GAGs and COL II and low level of COL I as that in normal cartilage. The in vitro and in vivo results indicated the present strategy could not only promote chondrogenesis of ASCs, but also facilitate hyaline-like cartilage regeneration with reduced fibrous tissue formation which may attenuate cartilage degradation in future long-term follow-up. PMID:26318814

  8. Characterization of the cellular origin of a tissue-engineered human phalanx model by in situ hybridization.

    Science.gov (United States)

    Chubinskaya, Susan; Jacquet, Robin; Isogai, Noritaka; Asamura, Shinichi; Landis, William J

    2004-01-01

    Tissue-engineered models of human phalanges have previously been fabricated from a combination of bovine periosteum, cartilage, tendon, and biodegradable polyglycolic acid and poly-L-lactic acid scaffolds. Resulting constructs implanted in athymic mice for more than 40 weeks developed new bone, cartilage, and tendon and became vascularized, but cell types comprising the constructs were unidentified. The origin of cells in middle phalanx models implanted for 20 weeks in nude mice has been studied by in situ hybridization analyzing species-specific gene expression. Oligonucleotide probes homologous to species-specific gene sequences of bovine type II and X collagen, aggrecan, bone sialoprotein, biglycan, and osteopontin, and mouse decorin were labeled with (35)S and hybridized to respective serial sections of bovine tissue, mouse tissue, and phalanx constructs. In situ hybridization showed positive message and tissue-specific localization for all bovine-specific probes examined within cartilaginous and midshaft portions of constructs and negative message for the mouse-specific decorin probe. These data show that osteoblasts and chondrocytes comprising constructs are derived exclusively from their original bovine sources over 20 weeks of implantation. Defining the cellular origin of the models lends insight into their biological, chemical, and physical nature and their growth and development. Maintenance of their initial genotype is crucial for future application of the models in augmenting impaired human phalanges and related tissues. PMID:15363176

  9. Solar System Exploration Augmented by In-Situ Resource Utilization: Human Mercury and Saturn Exploration

    Science.gov (United States)

    Palaszewski, Bryan

    2015-01-01

    Human and robotic missions to Mercury and Saturn are presented and analyzed. Unique elements of the local planetary environments are discussed and included in the analyses and assessments. Using historical studies of space exploration, in-situ resource utilization (ISRU), and industrialization all point to the vastness of natural resources in the solar system. Advanced propulsion benefitted from these resources in many way. While advanced propulsion systems were proposed in these historical studies, further investigation of nuclear options using high power nuclear thermal and nuclear pulse propulsion as well as advanced chemical propulsion can significantly enhance these scenarios. Updated analyses based on these historical visions will be presented. Nuclear thermal propulsion and ISRU enhanced chemical propulsion landers are assessed for Mercury missions. At Saturn, nuclear pulse propulsion with alternate propellant feed systems and Titan exploration with chemical propulsion options are discussed.

  10. Composition and photoelectrochemical properties of WO3/TNAs photoelectrodes fabricated by in situ electrochemical method

    International Nuclear Information System (INIS)

    TiO2/Ti Nanotube arrays (TNAs) and WO3/TNAs photoelectrodes were fabricated by in situ anodization and cycle pulse electrochemical deposition method. The morphology and structure were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra and X-ray photoelectron spectroscopy (XPS). Optical properties and photoelectrochemical (PECH) properties were investigated by surface photovoltage (SPV), ultra UV–vis diffuse reflectance spectra (UV/vis/DRS), open-circuit potential (OCP), and photocurrent density The results showed that WO3/TNAs photoelectrodes have excellent photoresponse performance. WO3 would enhance the photovoltage and photocurrent of TNAs photoelectrodes. The presence of WO3 caused red shift and enhanced the photosensitivity of TNAs photoelectrodes in whole light region

  11. Strip-drains for in situ clean up of contaminated fine-grained soils

    International Nuclear Information System (INIS)

    Methods for in situ remediation of contaminated soils, such as bioremediation, vacuum/air stripping and soil flushing have been found to be less effective under fine-grained soil conditions. To enhance the performance of these techniques, it was proposed that strip-drains or wick drains also known as prefabricated vertical (PV) drains be used. The research objective was to determine the feasibility of using PV drains to enhance the soil flushing process. Bench top and intermediate-scale laboratory experiments were conducted. An overview of the work, results and future considerations were presented. Results indicated that the technology is feasible. A preliminary model for the technology to be used in any field situation was developed. The model is currently being tested with data from physical experiments on both intermediate and field tests. 5 figs

  12. Power ultrasound effects for in situ compatibilization of polymer-clay nanocomposites

    International Nuclear Information System (INIS)

    Polymer-clay nanocomposites of various concentrations were prepared by ultrasonically assisted polymerization and melt mixing processes. The sonication process using power ultrasonic wave was employed to enhance nano-scale dispersion during melt mixing of monomer, polymer and organically modified clay. According to the unique mode of power ultrasound wave, we expected enhanced breakup of layered silicate bundle and further reduction in the size of dispersed phase with better homogeneity compared to the in situ polymerization. The optimum conditions to perform stable exfoliated nanocomposites were studied by various compositions and conditions. Dispersion characteristics and morphology of the nanocomposites were verified by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Rheological behaviors were measured under dynamic frequency sweep mode using Rheometric science ARES

  13. In situ reinforced polymers using low molecular weight compounds

    Science.gov (United States)

    Yordem, Onur Sinan

    2011-12-01

    The primary objective of this research is to generate reinforcing domains in situ during the processing of polymers by using phase separation techniques. Low molecular weight compounds were mixed with polymers where the process viscosity is reduced at process temperatures and mechanical properties are improved once the material system is cooled or reacted. Thermally induced phase separation and thermotropic phase transformation of low molar mass compounds were used in isotactic polypropylene (iPP) and poly(ether ether ketone) (PEEK) resins. Reaction induced phase separation was utilized in thermosets to generate anisotropic reinforcements. A new strategy to increase fracture toughness of materials was introduced. Simultaneously, enhancement in stiffness and reduction in process viscosity were also attained. Materials with improved rheological and mechanical properties were prepared by using thermotropic phase transformations of metal soaps in polymers (calcium stearate/iPP). Morphology and thermal properties were studied using WAXS, DSC and SEM. Mechanical and rheological investigation showed significant reduction in process viscosity and substantial improvement in fracture toughness were attained. Effects of molecular architecture of metal soaps were investigated in PEEK (calcium stearate/PEEK and sodium stearate/PEEK). The selected compounds reduced the process viscosity due to the high temperature co-continuous morphology of metal soaps. Unlike the iPP system that incorporates spherical particles, interaction between PEEK and metal soaps resulted in two discrete and co-continuous phases of PEEK and the metal stearates. DMA and melt rheology exhibited that sodium stearate/PEEK composites are stiffer. Effective moduli of secondary metal stearate phase were calculated using different composite theories, which suggested bicontinuous morphology to the metal soaps in PEEK. Use of low molecular weight crystallizable solvents was investigated in reactive systems. Formation of anisotropic reinforcements was evaluated using dimethyl sulfone (DMS) as the crystallizable diluent and diglycidyl ether of bisphenol-A (DGEBA)/m-phenylene diamine (mPDA) material system as the epoxy thermoset. Miscible blends of DMS and DGEBA/mPDA form homogenous mixtures that undergo polymerization induced phase separation, once the DGEBA oligomers react with mPDA. The effect of the competition between the crystallization and phase separation of DMS resulted in nano-wires to micro-scale fiber-like crystals that were generated by adjusting the reaction temperature and DMS concentration.

  14. The in-situ production of ash in pyroclastic flows

    Science.gov (United States)

    Manga, M.; Dufek, J.; Standish, D.

    2007-12-01

    Abrasion and fragmentation of pumice clasts during the propagation of pyroclastic flows has long been recognized as a potential source for the enhanced production of volcanic ash, however its relative importance has eluded quantification (Walker, 1981). The amount of ash produced in-situ can potentially affect runout distance, deposit sorting, the volume of ash introduced in the upper atmosphere, and internal pore pressure. We conduct a series of laboratory experiments on the collisional production of ash that may occur during different regimes of pyroclastic flow transport. We further parameterize the experiments of Cagnoli and Manga (2004) to determine the rate of production of frictional ash. We find that the energy of these interactions is insufficient to create a fractal particle size distribution; rather a bimodal suite of large particles and 10-100 micron ash particles are typically produced Using these laboratory experiments we can develop a subgrid model for ash production that can be included in analytical and multiphase numerical procedures to estimate the total volume of ash produced during transport. We examine numerically a range of initial flow energies and bed slopes over which the flows propagate. To simplify the problem we consider flows starting with 1 cm pumice clasts that can be broken up into 100 micron ash. We find that for most flow conditions10-20% of the initial 1 cm clasts comminutes into ash with the percentage increasing as a function of initial flow energy. Most of the ash is produced in the high-energy regions near the flow inlet, although flow acceleration on steep slopes can produce ash far from the vent. Ash produced at the frictional base of the flow and in the collisional upper regions of the flow can be redistributed through the entirety of the flow, although frictionally produced ash accumulates preferentially near its source in the bed-load. As slope increases, the relative proportion of ash generated by friction increases relative to collisional ash production in the upper regions of the flow. For most flow conditions the ash produced causes the flows to travel further and also increases the pore pressure in the flows.

  15. 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.

  16. In situ ARXPS characterization of tantalum based barrier films; In situ ARXPS Charakterisierung von tantalbasierten Barriereschichten

    Energy Technology Data Exchange (ETDEWEB)

    Gerlich, Lukas

    2012-11-16

    As a consequence of device shrinking the resistivity of the widely used TaN/Ta double barrier layer becomes an increasingly important parameter for device speed beyond the 32 nm technology node. In this study the optimization of the deposition of TaN/Ta stacks was performed in such a way that tantalum nitride layer thickness is minimized and tantalum grows in the favorable conducting alpha-phase. In the first part of the study in situ ARXPS was used to investigate the growth of different tantalum nitride layers on SiO{sub 2} and SiOCH as a function of deposition time, nitrogen flow and deposition power. In the second part the crystalline phase of 20 nm thick tantalum layers deposited on top of the same series of tantalum nitride layers characterized in the growth study was analyzed. The main findings are the appearance of tantalum carbide and tantalum silicide as interface species for the deposition on SiOCH and only tantalum silicide for the deposition on SiO{sub 2}. So alpha-tantalum grows preferably on tantalum carbide and nitrogen rich intermediate layers whereas silicide at the interface promotes the growth of beta-tantalum. To verify these findings two additional modific