Obtaining off-Hugoniot equation of state data on solid metals at extreme pressures via pulsed-power driven cylindrical liner implosions

Science.gov (United States)

Lemke, Raymond

2015-06-01

The focus of this talk is on magnetically driven, liner implosion experiments on the Z machine (Z) in which a solid, metal tube is shocklessly compressed to multi-megabar pressure. The goal of the experiments is to collect velocimetry data that can be used in conjunction with a new optimization based analysis technique to infer the principal isentrope of the tube material over a range of pressures. For the past decade, shock impact and ramp loading experiments on Z have used planar platforms exclusively. While producing state-of-the-art results for material science, it is difficult to produce drive pressures greater than 6 Mbar in the divergent planar geometry. In contrast, a cylindrical liner implosion is convergent; magnetic drive pressures approaching 50 Mbar are possible with the available current on Z (~ 20 MA). In our cylindrical experiments, the liner comprises an inner tube composed of the sample material (e.g., Ta) of unknown equation of state, and an outer tube composed of aluminum (Al) that serves as the current carrying cathode. Internal to the sample are fielded multiple PDV (Photonic Doppler Velocimetry) probes that measure velocity of the inner free surface of the imploding sample. External to the composite liner, at much larger radius, is an Al tube that is the return current anode. VISAR (velocity interferometry system for any reflector) probes measure free surface velocity of the exploding anode. Using the latter, MHD and optimization codes are employed to solve an inverse problem that yields the current driving the liner implosion. Then, the drive current, PDV velocity, MHD and optimization codes, are used to solve another inverse problem that yields pressure vs. density on approximately the principal isentrope of the sample material. Results for Ta, Re, and Cu compressed to ~ 10 Mbar are presented. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin

Laser solid sampling for a solid-state-detector ICP emission spectrometer

International Nuclear Information System (INIS)

Noelte, J.; Moenke-Blankenburg, L.; Schumann, T.

1994-01-01

Solid sampling with laser vaporization has been coupled to an ICP emission spectrometer with an Echelle optical system and a solid-state-detector for the analysis of steel and soil samples. Pulsation of the vaporized material flow was compensated by real-time background correction and internal standardization, resulting in good accuracy and precision. (orig.)

Mixed species radioiodine air sampling readout and dose assessment system

International Nuclear Information System (INIS)

Distenfeld, C.H.; Klemish, J.R. Jr.

1978-01-01

This invention provides a simple, reliable, inexpensive and portable means and method for determining the thyroid dose rate of mixed airborne species of solid and gaseous radioiodine without requiring highly skilled personnel, such as health physicists or electronics technicians. To this end, this invention provides a means and method for sampling a gas from a source of a mixed species of solid and gaseous radioiodine for collection of the mixed species and readout and assessment of the emissions therefrom by cylindrically, concentrically and annularly molding the respective species around a cylindrical passage for receiving a conventional probe-type Geiger-Mueller radiation detector

Attenuation correction for the collimated gamma ray assay of cylindrical samples

International Nuclear Information System (INIS)

Patra, Sabyasachi; Agarwal, Chhavi; Goswami, A.; Gathibandhe, M.

2015-01-01

The Hybrid Monte Carlo (HMC) method developed earlier for attenuation correction of non-collimated samples [Agarwal et al., 2008, Nucl. Instrum. Methods A 597, 198], has been extended to the segmented gamma ray assay of cylindrical samples. The method has been validated both experimentally and theoretically. For experimental validation, the results of HMC calculation have been compared with the experimentally obtained attenuation correction factors. The HMC attenuation correction factors have also been compared with the results obtained from literature available near-field and far-field formulae at two sample-to-detector distances (10.3 cm and 20.4 cm). The method has been found to be valid at all sample-to-detector distances over a wide range of transmittance. On the other hand, the literature available near-field and far-field formulae have been found to work over a limited range of sample-to detector distances and transmittances. The HMC method has been further extended to circular collimated geometries where analytical formula for attenuation correction does not exist. - Highlights: • Hybrid Monte Carlo method for attenuation correction developed for SGA system. • Method found to work for all sample-detector geometries for all transmittances. • The near-field formula applicable only after certain sample-detector distance. • The far-field formula applicable only for higher transmittances (>18%). • Hybrid Monte Carlo method further extended to circular collimated geometry

Flux pinning characteristics in cylindrical niobium samples used for superconducting radio frequency cavity fabrication

Science.gov (United States)

Dhavale, Asavari S.; Dhakal, Pashupati; Polyanskii, Anatolii A.; Ciovati, Gianluigi

2012-06-01

We present the results from DC magnetization and penetration depth measurements of cylindrical bulk large-grain (LG) and fine-grain (FG) niobium samples used for the fabrication of superconducting radio frequency (SRF) cavities. The surface treatment consisted of electropolishing and low-temperature baking as they are typically applied to SRF cavities. The magnetization data are analyzed using a modified critical state model. The critical current density Jc and pinning force Fp are calculated from the magnetization data and their temperature dependence and field dependence are presented. The LG samples have lower critical current density and pinning force density compared to FG samples, favorable to lower flux trapping efficiency. This effect may explain the lower values of residual resistance often observed in LG cavities than FG cavities.

Solid Loss of Carrots During Simulated Gastric Digestion

OpenAIRE

Kong, Fanbin; Singh, R. Paul

2010-01-01

The knowledge of solid loss kinetics of foods during digestion is crucial for understanding the factors that constrain the release of nutrients from the food matrix and their fate of digestion. The objective of this study was to investigate the solid loss of carrots during simulated gastric digestion as affected by pH, temperature, viscosity of gastric fluids, mechanical force present in stomach, and cooking. Cylindrical carrot samples were tested by static soaking method and using a model st...

Applications of Liquid-Phase Microextraction in the Sample Preparation of Environmental Solid Samples

Directory of Open Access Journals (Sweden)

Helena Prosen

2014-05-01

Full Text Available Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc. published in the last decade. Several innovative liquid-phase microextraction (LPME techniques that have emerged recently have also been applied as an aid in sample preparation of these samples: single-drop microextraction (SDME, hollow fiber-liquid phase microextraction (HF-LPME, dispersive liquid-liquid microextraction (DLLME. Besides the common organic solvents, surfactants and ionic liquids are also used. However, these techniques have to be combined with another technique to release the analytes from the solid sample into an aqueous solution. In the present review, the published methods were categorized into three groups: LPME in combination with a conventional solvent extraction; LPME in combination with an environmentally friendly extraction; LPME without previous extraction. The applicability of these approaches to the sample preparation for the determination of pollutants in solid environmental samples is discussed, with emphasis on their strengths, weak points and environmental impact.

Applications of liquid-phase microextraction in the sample preparation of environmental solid samples.

Science.gov (United States)

Prosen, Helena

2014-05-23

Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc.) published in the last decade. Several innovative liquid-phase microextraction (LPME) techniques that have emerged recently have also been applied as an aid in sample preparation of these samples: single-drop microextraction (SDME), hollow fiber-liquid phase microextraction (HF-LPME), dispersive liquid-liquid microextraction (DLLME). Besides the common organic solvents, surfactants and ionic liquids are also used. However, these techniques have to be combined with another technique to release the analytes from the solid sample into an aqueous solution. In the present review, the published methods were categorized into three groups: LPME in combination with a conventional solvent extraction; LPME in combination with an environmentally friendly extraction; LPME without previous extraction. The applicability of these approaches to the sample preparation for the determination of pollutants in solid environmental samples is discussed, with emphasis on their strengths, weak points and environmental impact.

Applications of Liquid-Phase Microextraction in the Sample Preparation of Environmental Solid Samples

OpenAIRE

Helena Prosen

2014-01-01

Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc.) published in the last decade. Several...

Flux pinning characteristics in cylindrical niobium samples used for superconducting radio frequency cavity fabrication

International Nuclear Information System (INIS)

Dhavale, Asavari S; Dhakal, Pashupati; Ciovati, Gianluigi; Polyanskii, Anatolii A

2012-01-01

We present the results from DC magnetization and penetration depth measurements of cylindrical bulk large-grain (LG) and fine-grain (FG) niobium samples used for the fabrication of superconducting radio frequency (SRF) cavities. The surface treatment consisted of electropolishing and low-temperature baking as they are typically applied to SRF cavities. The magnetization data are analyzed using a modified critical state model. The critical current density J c and pinning force F p are calculated from the magnetization data and their temperature dependence and field dependence are presented. The LG samples have lower critical current density and pinning force density compared to FG samples, favorable to lower flux trapping efficiency. This effect may explain the lower values of residual resistance often observed in LG cavities than FG cavities. (paper)

Assessing total and volatile solids in municipal solid waste samples.

Science.gov (United States)

Peces, M; Astals, S; Mata-Alvarez, J

2014-01-01

Municipal solid waste is broadly generated in everyday activities and its treatment is a global challenge. Total solids (TS) and volatile solids (VS) are typical control parameters measured in biological treatments. In this study, the TS and VS were determined using the standard methods, as well as introducing some variants: (i) the drying temperature for the TS assays was 105°C, 70°C and 50°C and (ii) the VS were determined using different heating ramps from room tempature to 550°C. TS could be determined at either 105°C or 70°C, but oven residence time was tripled at 70°C, increasing from 48 to 144 h. The VS could be determined by smouldering the sample (where the sample is burnt without a flame), which avoids the release of fumes and odours in the laboratory. However, smouldering can generate undesired pyrolysis products as a consequence of carbonization, which leads to VS being underestimated. Carbonization can be avoided using slow heating ramps to prevent the oxygen limitation. Furthermore, crushing the sample cores decreased the time to reach constant weight and decreased the potential to underestimate VS.

Procedures for sampling and sample-reduction within quality assurance systems for solid biofuels

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-04-15

The bias introduced when sampling solid biofuels from stockpiles or containers instead of from moving streams is assessed as well as the number and size of samples required to represent accurately the bulk sample, variations introduced when reducing bulk samples into samples for testing, and the usefulness of sample reduction methods. Details are given of the experimental work carried out in Sweden and Denmark using sawdust, wood chips, wood pellets, forestry residues and straw. The production of a model European Standard for quality assurance of solid biofuels is examined.

Paraffin scintillator for radioassay of solid support samples

International Nuclear Information System (INIS)

Fujii, Haruo; Takiue, Makoto

1989-01-01

A new paraffin scintillator used for solid support sample counting has been proposed, and its composition and various characteristics are described. The solid support sample treated with this scintillator can be easily handled because of rigid sample conditions. This technique provides great advantages such as the elimination of a large volume of scintillator and little radioactive waste material by using an economical polyethylene bag instead of the conventional counting vial. (author)

Axisymmetrical impulsive responses of an infinite circular cylindrical shell filled with liquid

International Nuclear Information System (INIS)

Ujihashi, Sadayuki; Matsumoto, Hiroyuki; Nakahara, Ichiro; Shigeta, Masayuki.

1986-01-01

In this paper, dynamic interaction phenomena on solid and liquid interfaces are discussed. Axisymmetrical responses of an infinite circular cylindrical shell perfectly filled with liquid are analyzed, based on Fluegge's theory for a circular cylindrical shell and the potential theory for the ideal fluid under conditions of the impulsive external band pressure given on the outer surface of the shell. The deflection and the moment of the shell and the pressure in the fluid are evaluated by using the numerical inversion of the Laplace transformation method. The approximate solution for the shell with an equivalent mass on it is analyzed and is evaluated, based on the solution for the solid and liquid interaction. (author)

Magnetic guns with cylindrical permanent magnets

Czech Academy of Sciences Publication Activity Database

Vokoun, David; Beleggia, M.; Heller, Luděk

2012-01-01

Roč. 324, č. 9 (2012), s. 1715-1719 ISSN 0304-8853 R&D Projects: GA ČR(CZ) GAP107/11/0391; GA AV ČR IAA100100920 Institutional research plan: CEZ:AV0Z10100520 Keywords : permanent magnet * cylindrical magnet * Earnshaw's theorem * magnetic gun * magnetostatic interaction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.826, year: 2012 http://www.sciencedirect.com/science/article/pii/S0304885311008997

Theoretical and experimental drying of a cylindrical sample by applying hot air and infrared radiation in an inert medium fluidized bed

Directory of Open Access Journals (Sweden)

B. Honarvar

2012-06-01

Full Text Available Drying of a cylindrical sample in a fluidized bed dryer containing inert particles was studied. For this purpose, a pilot-scaled fluidized bed dryer was constructed in which two different heat sources, hot air and infrared radiation were applied, and pieces of carrot were chosen as test samples. The heat transfer coefficient for cylindrical objects in a fluidized bed was also measured. The heat absorption coefficient for carrot was studied. The absorption coefficient can be computed by dividing the absorbed heat by the carrot to the heat absorbed for the water and black ink. In this regard, absorbed heat values by the carrot, water and black ink were used A mathematical model was proposed based on the mass and heat transfer phenomena within the drying sample. The results obtained by the proposed model were in favorable agreement with the experimental data.

NDT oriented equipment for observing the Doppler broadening of radiation produced by the annihilation of positrons in cylindrical samples

International Nuclear Information System (INIS)

Coleman, C.F.; Smith, F.A.; Hughes, A.E.

1976-11-01

This report describes the development of equipment for measuring annihilation line broadening in cylindrical samples a few millimetres in diameter, suitable for use in fatigue testing programs. A detached positron source is employed, allowing the samples to be scanned both longitudinally (resolution approximately 1 cm) and in azimuth. Some of the advantages of and problems associated with this configuration are discussed. The statistical precision of a number of parameters

Cr(VI) generation during sample preparation of solid samples – A ...

African Journals Online (AJOL)

Cr(VI) generation during sample preparation of solid samples – A chromite ore case study. R.I Glastonbury, W van der Merwe, J.P Beukes, P.G van Zyl, G Lachmann, C.J.H Steenkamp, N.F Dawson, M.H Stewart ...

A cylindrical specimen holder for electron cryo-tomography

International Nuclear Information System (INIS)

Palmer, Colin M.; Löwe, Jan

2014-01-01

The use of slab-like flat specimens for electron cryo-tomography restricts the range of viewing angles that can be used. This leads to the “missing wedge” problem, which causes artefacts and anisotropic resolution in reconstructed tomograms. Cylindrical specimens provide a way to eliminate the problem, since they allow imaging from a full range of viewing angles around the tilt axis. Such specimens have been used before for tomography of radiation-insensitive samples at room temperature, but never for frozen-hydrated specimens. Here, we demonstrate the use of thin-walled carbon tubes as specimen holders, allowing the preparation of cylindrical frozen-hydrated samples of ribosomes, liposomes and whole bacterial cells. Images acquired from these cylinders have equal quality at all viewing angles, and the accessible tilt range is restricted only by the physical limits of the microscope. Tomographic reconstructions of these specimens demonstrate that the effects of the missing wedge are substantially reduced, and could be completely eliminated if a full tilt range was used. The overall quality of these tomograms is still lower than that obtained by existing methods, but improvements are likely in future. - Highlights: • The missing wedge is a serious problem for electron cryo-tomography. • Cylindrical specimens allow the missing wedge to be eliminated. • Carbon nanopipettes can be used as cylindrical holders for tomography of frozen-hydrated specimens. • Cryo-tomography of cylindrical biological samples demonstrates a reduction of deleterious effects associated with the missing wedge

Contribution to study of interfaces instabilities in plane, cylindrical and spherical geometry

Science.gov (United States)

Toque, Nathalie

1996-12-01

This thesis proposes several experiments of hydrodynamical instabilities which are studied, numerically and theoretically. The experiments are in plane and cylindrical geometry. Their X-ray radiographies show the evolution of an interface between two solid media crossed by a detonation wave. These materials are initially solid. They become liquide under shock wave or stay between two phases, solid and liquid. The numerical study aims at simulating with the codes EAD and Ouranos, the interfaces instabilities which appear in the experiments. The experimental radiographies and the numerical pictures are in quite good agreement. The theoretical study suggests to modelise a spatio-temporal part of the experiments to obtain the quantitative development of perturbations at the interfaces and in the flows. The models are linear and in plane, cylindrical and spherical geometry. They preceed the inoming study of transition between linear and non linear development of instabilities in multifluids flows crossed by shock waves.

Fast sampling calorimetry with solid argon ionization chambers

International Nuclear Information System (INIS)

Clark, E.; Linn, S.; Piekarz, H.; Wahl, H.; Womersley, J.; Hansen, S.; Hurh, P.; Rivetta, C.; Sanders, R.; Schmitt, R.; Stanek, R.; Stefanik, A.

1992-01-01

A proposal for the fast sampling calorimetry with solid argon as active medium and the preliminary results from the solid argon test cell are presented. The proposed test calorimeter module structure, the signal routing and the mechanical and cryogenic arrangements are also discussed

A multilayered thick cylindrical shell under internal pressure and thermal loads applicable to solid propellant rocket motors

Energy Technology Data Exchange (ETDEWEB)

Renganathan, K.; Nageswara Rao, B.; Jana, M.K. [Vikram Sarabhai Space Centre, Trivandrum (India). Structural Engineering Group

2000-09-01

A solid propellant rocket motor can be considered to be made of various circumferential layers of different properties. A simple procedure is described here to obtain an analytical solution for the general case of multilayered thick cyclindrical shell for internal pressure and thermal loads. This analytical procedure is useful in the preliminary design analysis of solid propellant rocket motors. Since solid propellant material is of viscoelastic behaviour an approximate viscoelastic solution methodology for the multilayered shell is described for estimation of time dependent solutions of propellant grain in a rocket motor. The analytical solution for a two layer reinforced thick cylindrical shell available in the literature is shown to be a special case of the present analytical solution. The results from the present analytical solution for multilayers is found to be in good agreement with FEA results. (orig.) [German] Der grundlegende Aufbau von Feststoffraketenmotoren kann auf einen Zylinder aus mehreren Schichten mit unterschiedlichen Eigenschaften zurueckgefuehrt werden. Eine einfache Berechnungsprozedur fuer die analytische Loesung des allgemeinen Falles eines mehrschichtigen Zylinders unter innerem Druck und thermischer Belastung wird hier vorgestellt. Diese analytische Methodik ist fuer den Auslegungsprozess von Feststoffraketenmotoren von grundlegender Bedeutung. Das viskoelastische Fliessverhalten des festen Brennstoffes, das den zeitlichen Ablauf des Verbrennungsprozesses wesentlich bestimmt, wird durch ein Naeherungsverfahren gut erfasst. Ein in der Literatur enthaltenes spezielles Ergebnis fuer einen zweischaligen verstaerkten Zylinder ergibt sich als Sonderfall der hier vorgestellten Methodik. Die analytisch erhaltenen Loesungen fuer mehrschichtige Aufbauten sind in guter Uebereinstimmung mit mittels der FEM ermittelten Ergebnisse. (orig.)

High energy density matter issues related to future circular collider. Simulations of full beam impact with a solid copper cylindrical target

Energy Technology Data Exchange (ETDEWEB)

Tahir, N.A. [GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany); Burkart, F.; Schmidt, R.; Wollmann, D. [CERN-AB, Geneva (Switzerland); Shutov, A. [Institute of Problems of Chemical Physics, Chernogolovka (Russian Federation); Piriz, A.R. [E.T.S.I. Industrials, University of Castilla-La Mancha, Ciudad Real (Spain)

2017-11-15

This paper presents numerical simulations of the thermodynamic and hydrodynamic response of a solid copper cylindrical target that is subjected to the full impact of one future circular collider (FCC) ultra-relativistic proton beam. The target is facially irradiated so that the beam axis coincides with the cylinder axis. The simulations have been carried out employing an energy deposition code, FLUKA, and a 2D hydrodynamic code, BIG2, iteratively. The simulations show that, although the static range of a single FCC proton and its shower in solid copper is ∝1.5 m, the full beam may penetrate up to 350 m into the target as a result of hydrodynamic tunnelling. Moreover, simulations also show that a major part of the target is converted into high energy density (HED) matter, including warm dense matter (WDM) and strongly coupled plasma. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Fast calculation method for computer-generated cylindrical holograms.

Science.gov (United States)

Yamaguchi, Takeshi; Fujii, Tomohiko; Yoshikawa, Hiroshi

2008-07-01

Since a general flat hologram has a limited viewable area, we usually cannot see the other side of a reconstructed object. There are some holograms that can solve this problem. A cylindrical hologram is well known to be viewable in 360 deg. Most cylindrical holograms are optical holograms, but there are few reports of computer-generated cylindrical holograms. The lack of computer-generated cylindrical holograms is because the spatial resolution of output devices is not great enough; therefore, we have to make a large hologram or use a small object to fulfill the sampling theorem. In addition, in calculating the large fringe, the calculation amount increases in proportion to the hologram size. Therefore, we propose what we believe to be a new calculation method for fast calculation. Then, we print these fringes with our prototype fringe printer. As a result, we obtain a good reconstructed image from a computer-generated cylindrical hologram.

Spin imaging in solids using synchronously rotating field gradients and samples

International Nuclear Information System (INIS)

Wind, R.A.; Yannoni, C.S.

1983-01-01

A method for spin-imaging in solids using nuclear magnetic resonance (NMR) spectroscopy is described. With this method, the spin density distribution of a two- or three-dimensional object such as a solid can be constructed resulting in an image of the sample. This method lends itself to computer control to map out an image of the object. This spin-imaging method involves the steps of placing a solid sample in the rf coil field and the external magnetic field of an NMR spectrometer. A magnetic field gradient is superimposed across the sample to provide a field gradient which results in a varying DC field that has different values over different parts of the sample. As a result, nuclei in different parts of the sample have different resonant NMR frequencies. The sample is rotated about an axis which makes a particular angle of 54.7 degrees with the static external magnetic field. The magnetic field gradient which has a spatial distribution related to the sample spinning axis is then rotated synchronously with the sample. Data is then collected while performing a solid state NMR line narrowing procedure. The next step is to change the phase relation between the sample rotation and the field gradient rotation. The data is again collected as before while the sample and field gradient are synchronously rotated. The phase relation is changed a number of times and data collected each time. The spin image of the solid sample is then reconstructed from the collected data

Automated, Ultra-Sterile Solid Sample Handling and Analysis on a Chip

Science.gov (United States)

Mora, Maria F.; Stockton, Amanda M.; Willis, Peter A.

2013-01-01

There are no existing ultra-sterile lab-on-a-chip systems that can accept solid samples and perform complete chemical analyses without human intervention. The proposed solution is to demonstrate completely automated lab-on-a-chip manipulation of powdered solid samples, followed by on-chip liquid extraction and chemical analysis. This technology utilizes a newly invented glass micro-device for solid manipulation, which mates with existing lab-on-a-chip instrumentation. Devices are fabricated in a Class 10 cleanroom at the JPL MicroDevices Lab, and are plasma-cleaned before and after assembly. Solid samples enter the device through a drilled hole in the top. Existing micro-pumping technology is used to transfer milligrams of powdered sample into an extraction chamber where it is mixed with liquids to extract organic material. Subsequent chemical analysis is performed using portable microchip capillary electrophoresis systems (CE). These instruments have been used for ultra-highly sensitive (parts-per-trillion, pptr) analysis of organic compounds including amines, amino acids, aldehydes, ketones, carboxylic acids, and thiols. Fully autonomous amino acid analyses in liquids were demonstrated; however, to date there have been no reports of completely automated analysis of solid samples on chip. This approach utilizes an existing portable instrument that houses optics, high-voltage power supplies, and solenoids for fully autonomous microfluidic sample processing and CE analysis with laser-induced fluorescence (LIF) detection. Furthermore, the entire system can be sterilized and placed in a cleanroom environment for analyzing samples returned from extraterrestrial targets, if desired. This is an entirely new capability never demonstrated before. The ability to manipulate solid samples, coupled with lab-on-a-chip analysis technology, will enable ultraclean and ultrasensitive end-to-end analysis of samples that is orders of magnitude more sensitive than the ppb goal given

Direct Observation of the Phenomenology of a Solid Thermal Explosion Using Time-Resolved Proton Radiography

International Nuclear Information System (INIS)

Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Schwartz, C. L.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; McNeil, W.; Rightley, P.; Marr-Lyon, M.

2008-01-01

We present a new phenomenology for burn propagation inside a thermal explosion based on dynamic radiography. Radiographic images were obtained of an aluminum cased solid cylindrical sample of a plastic bonded formulation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine. The phenomenology observed is ignition followed by cracking in the solid accompanied by the propagation of a radially symmetric front of increasing proton transmission. This is followed by a further increase in transmission through the sample, ending after approximately 100 μs. We show that these processes are consistent with the propagation of a convective burn front followed by consumption of the remaining solid by conductive particle burning

The decrease of cylindrical pempek quality during boiling

Science.gov (United States)

Karneta, R.; Gultom, N. F.

2017-09-01

The research objective was to study the effects of temperature and formulation on quality of pempek lenjer during boiling. Treatments in this study were four levels of pempek formulation and five levels of temperature. Data was processed by using analysis of variance (Anova). If test results showed that samples were significantly different or highly significantly different, then further test was conducted by using Honestly Significant Different. The results showed that chemical analysis showed that fish dominant formula of cylindrical pempek had higher water content, protein content, lipid content and ash content than that of tapioca starch dominant formula, but it had lower carbohydrate content and fibre content than that of tapioca starch dominant formula.The higher the temperature at center point of cylindrical pempek, the lower the chemical quality of cylindrical pempek. The effect of formula on physical quality of cylindrical pempek showed that tapioca starch dominant formula had more rubbery texture, more neutral pH and brighter color than that of fish dominant formula.The temperature change had no significant effect on texture and pH of cylindrical pempek, but it had significant effect on lightness, intensity and chromatic color especially after exceeding optimum time of boiling.

Study of a solid state micro-dosemeter based on a monolithic silicon telescope: Irradiations with low-energy neutrons and direct comparison with a cylindrical TEPC

International Nuclear Information System (INIS)

Agosteo, S.; Colautti, P.; Fanton, I.; Fazzi, A.; Introini, M. V.; Moro, D.; Pola, A.; Varoli, V.

2011-01-01

A silicon device based on the monolithic silicon telescope technology coupled to a tissue-equivalent converter was proposed and investigated for solid state microdosimetry. The detector is constituted by a DE stage about 2 μm in thickness geometrically segmented in a matrix of micrometric diodes and a residual-energy measurement stage E about 500 μm in thickness. Each thin diode has a cylindrical sensitive volume 9 μm in nominal diameter, similar to that of a cylindrical tissue-equivalent proportional counter (TEPC). The silicon device and a cylindrical TEPC were irradiated in the same experimental conditions with quasi-monoenergetic neutrons of energy between 0.64 and 2.3 MeV at the INFN-Legnaro National Laboratories (LNLINFN, Legnaro (Italy)). The aim was to study the capability of the silicon-based system of reproducing microdosimetric spectra similar to those measured by a reference micro-dosemeter. The TEPC was set in order to simulate a tissue site about 2 μm in diameter. The spectra of the energy imparted to the ΔE stage of the silicon telescope were corrected for tissue-equivalence through an optimized procedure that exploits the information from the residual energy measurement stage E. A geometrical correction based on parametric criteria for shape-equivalence was also applied. The agreement between the dose distributions of lineal energy and the corresponding mean values is satisfactory at each neutron energy considered. (authors)

Chaotic Dynamics of Cage Behavior in a High-Speed Cylindrical Roller Bearing

Directory of Open Access Journals (Sweden)

Long Chen

2016-01-01

Full Text Available This paper presents a mathematical model to investigate the nonlinear dynamic behavior of cage in high-speed cylindrical bearing. Variations of cage behavior due to varying cage eccentricity and cage guidance gap are observed. Hydrodynamic behavior in cage contacts is taken into consideration for a more realistic calculation of acting forces owing to high working speed. Analysis of real-time cage dynamic behavior on radial plane is carried out using chaos theory based on the theoretical and mathematical model established in the paper. The analytical results of this paper provide a solid foundation for designing and manufacturing of high-speed cylindrical roller bearing.

Solid state characterization of commercial crystalline and amorphous atorvastatin calcium samples.

Science.gov (United States)

Shete, Ganesh; Puri, Vibha; Kumar, Lokesh; Bansal, Arvind K

2010-06-01

Atorvastatin calcium (ATC), an anti-lipid BCS class II drug, is marketed in crystalline and amorphous solid forms. The objective of this study was to perform solid state characterization of commercial crystalline and amorphous ATC drug samples available in the Indian market. Six samples each of crystalline and amorphous ATC were characterized using X-ray powder diffractometry (XRPD), differential scanning calorimetry (DSC), thermogravimetric analysis, Karl Fisher titrimetry, microscopy (hot stage microscopy, scanning electron microscopy), contact angle, and intrinsic dissolution rate (IDR). All crystalline ATC samples were found to be stable form I, however one sample possessed polymorphic impurity, evidenced in XRPD and DSC analysis. Amongst the amorphous ATC samples, XRPD demonstrated five samples to be amorphous 'form 27', while, one matched amorphous 'form 23'. Thermal behavior of amorphous ATC samples was compared to amorphous ATC generated by melt quenching in DSC. ATC was found to be an excellent glass former with T(g)/T(m) of 0.95. Residual crystallinity was detected in two of the amorphous samples by complementary use of conventional and modulated DSC techniques. The wettability and IDR of all amorphous samples was found to be higher than the crystalline samples. In conclusion, commercial ATC samples exhibited diverse solid state behavior that can impact the performance and stability of the dosage forms.

Improved Riccati Transfer Matrix Method for Free Vibration of Non-Cylindrical Helical Springs Including Warping

Directory of Open Access Journals (Sweden)

A.M. Yu

2012-01-01

Full Text Available Free vibration equations for non-cylindrical (conical, barrel, and hyperboloidal types helical springs with noncircular cross-sections, which consist of 14 first-order ordinary differential equations with variable coefficients, are theoretically derived using spatially curved beam theory. In the formulation, the warping effect upon natural frequencies and vibrating mode shapes is first studied in addition to including the rotary inertia, the shear and axial deformation influences. The natural frequencies of the springs are determined by the use of improved Riccati transfer matrix method. The element transfer matrix used in the solution is calculated using the Scaling and Squaring method and Pad'e approximations. Three examples are presented for three types of springs with different cross-sectional shapes under clamped-clamped boundary condition. The accuracy of the proposed method has been compared with the FEM results using three-dimensional solid elements (Solid 45 in ANSYS code. Numerical results reveal that the warping effect is more pronounced in the case of non-cylindrical helical springs than that of cylindrical helical springs, which should be taken into consideration in the free vibration analysis of such springs.

Behavior of instantaneous lateral velocity and flow pulsation in duct flow with cylindrical rod

International Nuclear Information System (INIS)

Lee, Chi Young; Shin, Chang Hwan; Park, Ju Yong; Oh, Dong Seok; Chun, Tae Hyun; In, Wang Kee

2012-01-01

Recently, KAERI (Korea Atomic Energy Research Institute) has examined and developed a dual cooled annular fuel. Dual cooled annular fuel allows the coolant to flow through the inner channel as well as the outer channel. Due to inner channel, the outer diameter of dual cooled annular fuel (15.9 mm) is larger than that of conventional cylindrical solid fuel (9.5 mm). Hence, dual cooled annular fuel assembly becomes a tight lattice fuel bundle configuration to maintain the same array size and guide tube locations as cylindrical solid fuel assembly. P/Ds (pitch between rods to rod diameter ratio) of dual cooled annular and cylindrical solid fuel assemblies are 1.08 and 1.35, respectively. This difference of P/D could change the behavior of turbulent flow in rod bundle. Our research group has investigated a turbulent flow parallel to the fuel rods using two kinds of simulated 3x3 rod bundles. To measure the turbulent rod bundle flow, PIV (Particle Image Velocimetry) and MIR (Matching Index of Refraction) techniques were used. In a simulated dual cooled annular fuel bundle (i.e., P/D=1.08), the quasi periodic oscillating flow motion in the lateral direction, called the flow pulsation, was observed, which significantly increased the lateral turbulence intensity at the rod gap center. The flow pulsation was visualized and measured clearly and successfully by PIV and MIR techniques. Such a flow motion may have influence on the fluid induced vibration, heat transfer, CHF (Critical Heat Flux), and flow mixing between subchannels in rod bundle flow. On the other hand, in a simulated cylindrical solid fuel bundle (i.e., P/D=1.35), the peak of turbulence intensity at the gap center was not measured due to an irregular motion of the lateral flow. This study implies that the behavior of lateral velocity in rod bundle flow is greatly influenced by the P/D (i.e., gap distance). In this work, the influence of gap distance on behavior of instantaneous lateral velocity and flow

Solid-phase microextraction for the analysis of biological samples

NARCIS (Netherlands)

Theodoridis, G; Koster, EHM; de Jong, GJ

2000-01-01

Solid-phase microextraction (SPME) has been introduced for the extraction of organic compounds from environmental samples. This relatively new extraction technique has now also gained a lot of interest in a broad field of analysis including food, biological and pharmaceutical samples. SPME has a

A Clustering Method for Data in Cylindrical Coordinates

Directory of Open Access Journals (Sweden)

Kazuhisa Fujita

2017-01-01

Full Text Available We propose a new clustering method for data in cylindrical coordinates based on the k-means. The goal of the k-means family is to maximize an optimization function, which requires a similarity. Thus, we need a new similarity to obtain the new clustering method for data in cylindrical coordinates. In this study, we first derive a new similarity for the new clustering method by assuming a particular probabilistic model. A data point in cylindrical coordinates has radius, azimuth, and height. We assume that the azimuth is sampled from a von Mises distribution and the radius and the height are independently generated from isotropic Gaussian distributions. We derive the new similarity from the log likelihood of the assumed probability distribution. Our experiments demonstrate that the proposed method using the new similarity can appropriately partition synthetic data defined in cylindrical coordinates. Furthermore, we apply the proposed method to color image quantization and show that the methods successfully quantize a color image with respect to the hue element.

Cylindrical neutron generator

Science.gov (United States)

Leung, Ka-Ngo [Hercules, CA

2008-04-22

A cylindrical neutron generator is formed with a coaxial RF-driven plasma ion source and target. A deuterium (or deuterium and tritium) plasma is produced by RF excitation in a cylindrical plasma ion generator using an RF antenna. A cylindrical neutron generating target is coaxial with the ion generator, separated by plasma and extraction electrodes which contain many slots. The plasma generator emanates ions radially over 360.degree. and the cylindrical target is thus irradiated by ions over its entire circumference. The plasma generator and target may be as long as desired. The plasma generator may be in the center and the neutron target on the outside, or the plasma generator may be on the outside and the target on the inside. In a nested configuration, several concentric targets and plasma generating regions are nested to increase the neutron flux.

Mathematical simulation of stressed-deformed state in rod cylindrical fuel elemnts KONDOR program

International Nuclear Information System (INIS)

Khmelevskij, M.Ya.; Malakhova, E.I.; Dolmatov, P.S.

1987-01-01

A mathematical model for numerical computation of stressed-deformed stae in a rod cylindrical fuel element is developed. The model is based on preliminary discretization of the design scheme and linearization of radial parameters as radius functions. The formulation generality enables to calculate strength parameter kinetics in any circular cylindrical fuel element (e.g. annular fuel element; solid or tubular core; ceramic, metallic or dispersion fuel) for arbitrary transient operating conditions and taking into account all possible loading factors. The method is realized in the KONDOR programm (FORTRAN, ES-1061 computer). An example illustrating computation of stress kinetics in a fast reactor fuel element during transient operation is given

Solid State Characterization of Commercial Crystalline and Amorphous Atorvastatin Calcium Samples

OpenAIRE

Shete, Ganesh; Puri, Vibha; Kumar, Lokesh; Bansal, Arvind K.

2010-01-01

Atorvastatin calcium (ATC), an anti-lipid BCS class II drug, is marketed in crystalline and amorphous solid forms. The objective of this study was to perform solid state characterization of commercial crystalline and amorphous ATC drug samples available in the Indian market. Six samples each of crystalline and amorphous ATC were characterized using X-ray powder diffractometry (XRPD), differential scanning calorimetry (DSC), thermogravimetric analysis, Karl Fisher titrimetry, microscopy (hot s...

Bounds of thermal stability of infinite cylindrical structures with non-uniform internal heat generation

International Nuclear Information System (INIS)

Gadalla, M.A.

1992-01-01

This paper presents an overview analyses of the thermal instability or thermal viability of infinite cylindrical structures with non-linear and non-uniform internal heat generation. The structure may be subjected to different and combined boundary conditions. An analytical solution is obtained for the generalized problem in spite of the non-linearity and the non-homogeneity of the source term. Four case studies with different boundary conditions are presented. The analyses show that the critical parameter for thermal stability may be though of as an altitude of surface below which the cylindrical structure will be thermally stable and performance worthy. The results also show that the bounds of thermal stability of a cylindrical structure system (solid or hollow) is eminently determined by the boundary conditions to which the system is subjected and can significantly alter the life-span of the structure

Curvature-insensitive methodology for thermal-wave depth-profilometry in multi-layered curvilinear solids

International Nuclear Information System (INIS)

Liu Liwang; Wang Chinhua; Yuan Xiao; Mandelis, Andreas

2010-01-01

A generalized similarity normalization (SN) methodology for characterizing depth profiles of continuously varying thermophysical properties in curvilinear (cylindrical and spherical) solids is presented. Specifically, the principle and the physical mechanism of the elimination of the surface curvature effect from the overall photothermal signal is introduced based on theoretical models of cylindrical, spherical and flat solids with multi-layer structures. The effects of the relative values of radii of curvature of the curvilinear solid, the thickness of the inhomogeneous surface layer and the measurement azimuthal angle on the validity of the technique are discussed in detail. Experimental reconstructions of thermophysical depth profiles of hardened cylindrical steel rods of various diameters are performed based on both curvilinear theory and the equivalent flat surface theory. The reconstructed results are compared and validated.

Simulation study comparing the helmet-chin PET with a cylindrical PET of the same number of detectors

Science.gov (United States)

Ahmed, Abdella M.; Tashima, Hideaki; Yoshida, Eiji; Nishikido, Fumihiko; Yamaya, Taiga

2017-06-01

There is a growing interest in developing brain PET scanners with high sensitivity and high spatial resolution for early diagnosis of neurodegenerative diseases and studies of brain functions. Sensitivity of the PET scanner can be improved by increasing the solid angle. However, conventional PET scanners are designed based on a cylindrical geometry, which may not be the most efficient design for brain imaging in terms of the balance between sensitivity and cost. We proposed a dedicated brain PET scanner based on a hemispheric shape detector and a chin detector (referred to as the helmet-chin PET), which is designed to maximize the solid angle by increasing the number of lines-of-response in the hemisphere. The parallax error, which PET scanners with a large solid angle tend to have, can be suppressed by the use of depth-of-interaction detectors. In this study, we carry out a realistic evaluation of the helmet-chin PET using Monte Carlo simulation based on the 4-layer GSO detector which consists of a 16  ×  16  ×  4 array of crystals with dimensions of 2.8  ×  2.8  ×  7.5 mm3. The purpose of this simulation is to show the gain in imaging performance of the helmet-chin PET compared with the cylindrical PET using the same number of detectors in each configuration. The sensitivity of the helmet-chin PET evaluated with a cylindrical phantom has a significant increase, especially at the top of the (field-of-view) FOV. The peak-NECR of the helmet-chin PET is 1.4 times higher compared to the cylindrical PET. The helmet-chin PET provides relatively low noise images throughout the FOV compared to the cylindrical PET which exhibits enhanced noise at the peripheral regions. The results show the helmet-chin PET can significantly improve the sensitivity and reduce the noise in the reconstructed images.

An approach for sampling solid heterogeneous waste at the Hanford Site waste receiving and processing and solid waste projects

International Nuclear Information System (INIS)

Sexton, R.A.

1993-03-01

This paper addresses the problem of obtaining meaningful data from samples of solid heterogeneous waste while maintaining sample rates as low as practical. The Waste Receiving and Processing Facility, Module 1, at the Hanford Site in south-central Washington State will process mostly heterogeneous solid wastes. The presence of hazardous materials is documented for some packages and unknown for others. Waste characterization is needed to segregate the waste, meet waste acceptance and shipping requirements, and meet facility permitting requirements. Sampling and analysis are expensive, and no amount of sampling will produce absolute certainty of waste contents. A sampling strategy is proposed that provides acceptable confidence with achievable sampling rates

Study of thermal neutron currents near cylindrical absorbers located in heavy water

International Nuclear Information System (INIS)

Simard, Y.N.

1973-01-01

The experiments reported involved determining the angular response of detectors to neutrons exterior to the surface of long cylindrical absorbers immersed in a scattering medium. The absorbers consisted of solid cylinders of copper, cadmium, or natural uranium in a fuel lattice, and combinations of copper and cadmium, as well as voided cylinders. The scattering (moderating) medium consisted of heavy water. (author)

Nonlinear mechanics of surface growth for cylindrical and spherical elastic bodies

Science.gov (United States)

Sozio, Fabio; Yavari, Arash

2017-01-01

In this paper we formulate the initial-boundary value problems of accreting cylindrical and spherical nonlinear elastic solids in a geometric framework. It is assumed that the body grows as a result of addition of new (stress-free or pre-stressed) material on part of its boundary. We construct Riemannian material manifolds for a growing body with metrics explicitly depending on the history of applied external loads and deformation during accretion and the growth velocity. We numerically solve the governing equilibrium equations in the case of neo-Hookean solids and compare the accretion and residual stresses with those calculated using the linear mechanics of surface growth.

The Theory of the Reentrant Effect in Susceptibility of Cylindrical Mesoscopic Samples

International Nuclear Information System (INIS)

Gogadze, G.A.

2006-01-01

A theory has been developed to explain the anomalous behavior of the magnetic susceptibility of a normal metal-superconductor (NS) structure in weak magnetic fields at milli kelvin temperatures. The effect was discovered experimentally [A. C. Mota et al., Phys. Rev. Lett. 65, 1514 (1990)]. In cylindrical superconducting samples covered with a thin normal pure metal layer, the susceptibility exhibited a reentrant effect: it started to increase unexpectedly when the temperature was lowered below 100 mK. The effect was observed in mesoscopic NS structures when the N and S metals were in good electric contact. The theory proposed is essentially based on the properties of the Andreev levels in the normal metal. When the magnetic field (or temperature) changes, each of the Andreev levels coincides from time to time with the chemical potential of the metal. As a result, the state of the NS structure experiences strong degeneracy, and the quasiparticle density of states exhibits resonance spikes. This generates a large paramagnetic contribution to the susceptibility, which adds to the diamagnetic contribution, thus leading to the reentrant effect. The explanation proposed was obtained within the model of free electrons. The theory provides a good description of the experimental results

Solid Phase Characterization of Tank 241-C-105 Grab Samples

International Nuclear Information System (INIS)

Ely, T. M.; LaMothe, M. E.; Lachut, J. S.

2016-01-01

The solid phase characterization (SPC) of three grab samples from single-shell Tank 241-C-105 (C-105) that were received at the laboratory the week of October 26, 2015, has been completed. The three samples were received and broken down in the 11A hot cells.

Energy corrections in pulsed neutron measurements for cylindrical geometry

International Nuclear Information System (INIS)

Drozdowicz, K.; Woznicka, U.

1982-01-01

A solution of the thermal neutron diffusion equation for a two-region concentric cylindrical system, with a constant neutron flux in the inner medium assumed, is given. The velocity-averaged dynamic parameters for thermal neutrons are used in the method. The corrections due to the diffusion cooling are introduced into the dynamic material buckling and into the velocity distribution of the thermal neutron flux. Detailed relations obtained for a hydrogenous moderator are given. Results of the measurements of the thermal neutron macroscopic absorption cross-sections for the samples in the two-region cylindrical systems are presented. (author)

Telescoping cylindrical piezoelectric fiber composite actuator assemblies

Science.gov (United States)

Allison, Sidney G. (Inventor); Shams, Qamar A. (Inventor); Fox, Robert L. (Inventor); Fox, legal representative, Christopher L. (Inventor); Fox Chattin, legal representative, Melanie L. (Inventor)

2010-01-01

A telescoping actuator assembly includes a plurality of cylindrical actuators in a concentric arrangement. Each cylindrical actuator is at least one piezoelectric fiber composite actuator having a plurality of piezoelectric fibers extending parallel to one another and to the concentric arrangement's longitudinal axis. Each cylindrical actuator is coupled to concentrically-adjacent ones of the cylindrical actuators such that the plurality of cylindrical actuators can experience telescopic movement. An electrical energy source coupled to the cylindrical actuators applies actuation energy thereto to generate the telescopic movement.

The evolution of solid density within a thermal explosion II. Dynamic proton radiography of cracking and solid consumption by burning

International Nuclear Information System (INIS)

Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Grim, G.; Mariam, F.; Schwartz, C. L.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; Espinoza, C.; Lewis, D.; Bainbridge, J.; McNeil, W.; Rightley, P.

2012-01-01

We report proton transmission images obtained subsequent to the laser assisted thermal ignition of a sample of PBX 9501 (a plastic bonded formulation of the explosive nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)). We describe the laser assisted thermal ignition technique as a means to synchronize a non-linear thermal ignition event while preserving the subsequent post-ignition behavior. We have obtained dynamic proton transmission images at two spatial magnifications and viewed both the radial and transverse axis of a solid cylindrical sample encased in aluminum. Images have been obtained with 3 to 15 μs temporal resolution and approximately 100 μm spatial resolution at the higher magnification. We observe case expansion from very early in the experiment, until case fragmentation. We observe spatially anisotropic features in the transmission which we attribute to cracking in the solid explosive, in agreement with previous measurements conducted on two dimensional samples with optical viewing. Digital analysis of the images also reveals spatially isotropic features which we attribute to the evolution of the loss of density by burning subsequent to thermal ignition.

The evolution of solid density within a thermal explosion II. Dynamic proton radiography of cracking and solid consumption by burning

Energy Technology Data Exchange (ETDEWEB)

Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Grim, G.; Mariam, F.; Schwartz, C. L.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; Espinoza, C.; Lewis, D.; Bainbridge, J.; McNeil, W.; Rightley, P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); and others

2012-05-15

We report proton transmission images obtained subsequent to the laser assisted thermal ignition of a sample of PBX 9501 (a plastic bonded formulation of the explosive nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)). We describe the laser assisted thermal ignition technique as a means to synchronize a non-linear thermal ignition event while preserving the subsequent post-ignition behavior. We have obtained dynamic proton transmission images at two spatial magnifications and viewed both the radial and transverse axis of a solid cylindrical sample encased in aluminum. Images have been obtained with 3 to 15 {mu}s temporal resolution and approximately 100 {mu}m spatial resolution at the higher magnification. We observe case expansion from very early in the experiment, until case fragmentation. We observe spatially anisotropic features in the transmission which we attribute to cracking in the solid explosive, in agreement with previous measurements conducted on two dimensional samples with optical viewing. Digital analysis of the images also reveals spatially isotropic features which we attribute to the evolution of the loss of density by burning subsequent to thermal ignition.

Confined detonations with cylindrical and spherical symmetry

International Nuclear Information System (INIS)

Linan, A.; Lecuona, A.

1979-01-01

An imploding spherical or cylindrical detonation, starting in the interface of the detonantion with an external inert media, used as a reflector, creates on it a strong shock wave moving outward from the interface. An initially weak shock wave appears in the detonated media that travels toward the center, and it could reach the detonation wave, enforcing it in its process of implosion. To describe the fluid field, the Euler s equations are solved by means of expansions valid for the early stages of the process. Isentropic of the type P/pγ-K for the detonated and compressed inert media are used. For liquid or solid reflectors a more appropriate equation is used. (Author) 8 refs

Effect of the shape and size of dosimeters on the response of solid state/EPR dosimetry

International Nuclear Information System (INIS)

Yordanov, Nicola D.; Fabisiak, Slawomir; Lagunov, Oleg

2006-01-01

The influence of the shape and size of dosimeters used in solid state-EPR (SS/EPR) dosimetry on their response is reported. It is shown that for commonly used cylindrical (rod) shaped dosimeters of equal height, prepared of low (ε=<3) dielectric constant materials, linearity between their volume and the EPR response is observed when their diameter varies between 3 and 5mm. Further increase of the dosimeter's diameter is not recommended since the increased penetration of the dosimeter material into the electric component of the microwave field in the EPR cavity increases the dielectric losses and decreases the EPR response. In an attempt to improve the sensitivity of the SS/EPR dosimetry we have prepared and tested new, flat-shaped, dosimeters of low (ε∼2) dielectric constant materials which were found to exhibit: (i) linear EPR response within 1-5mm thickness; (ii) higher sensitivity than cylindrical dosimeters at equal sample volume; (iii) increased by ca. 270% EPR sensitivity at 5mm thickness compared to the cylindrical dosimeters with the same diameter (ca. 1.7 times increased sample volume). Using flat shape dosimeters of suitable size provides 2.7 times higher EPR sensitivity of single estimation

Solid Phase Characterization Of Heel Samples From Tank 241-C-110

International Nuclear Information System (INIS)

Page, J.S.; Cooke, G.A.; Pestovich, J.A.; Huber, H.J.

2011-01-01

During sluicing operations of tank 241-C-110, a significant amount of solids were unable to be retrieved. These solids (often referred to as the tank 'heel') were sampled in 2010 and chemically and mineralogically analyzed in the 222-S Laboratory. Additionally, dissolution tests were performed to identify the amount of undissolvable material after using multiple water contacts. This report covers the solid phase characterization of six samples from these tests using scanning electron microscopy, polarized light microscopy, and X-ray diffraction. The chemical analyses, particle size distribution analysis, and dissolution test results are reported separately. Two of the samples were from composites created from as-received material - Composite A and Composite B. The main phase in these samples was sodium-fluoride-phosphate hydrate (natrophosphate) - in the X-ray diffraction spectra, this phase was the only phase identifiable. Polarized light microscopy showed the presence of minor amounts of gibbsite and other phases. These phases were identified by scanning electron microscopy - energy dispersive X-ray spectroscopy as sodium aluminosilicates, sodium diuranate, and sodium strontium phosphate hydrate (nastrophite) crystals. The natrophosphate crystals in the scanning electron microscopy analysis showed a variety of erosive and dissolution features from perfectly shaped octahedral to well-rounded appearance. Two samples were from water-washed Composites A and B, with no change in mineralogy compared to the as-received samples. This is not surprising, since the water wash had only a short period of water contact with the material as opposed to the water dissolution tests. The last two samples were residual solids from the water dissolution tests. These tests included multiple additions of water at 15 C and 45 C. The samples were sieved to separate a coarser fraction of > 710 μm and a finer fraction of < 710 μm. These two fractions were analyzed separately. The coarser

Removal of batteries from solid waste using trommel separation.

Science.gov (United States)

Lau, S T; Cheung, W H; Kwong, C K; Wan, C P; Choy, K K H; Leung, C C; Porter, J F; Hui, C W; Mc Kay, G

2005-01-01

This paper describes the design and testing of a trommel for separation of batteries from solid waste. A trommel is a cylindrical separation device that rotates and performs size separation. It has also been used in areas such as municipal solid waste (MSW) processing, classifying construction and demolition debris, screening mass-burn incinerator ash and compost processing. A trommel has been designed based on size separation to separate household batteries from solid waste, which can then be used as feedstock for alternative applications of solid waste combustion, particularly where the metal content of the product is also a critical parameter, such as the Co-Co process for integrated cement and power production. This trommel has been tested with batches of university office and restaurant wastes against various factors. The recovery efficiency of batteries increases with decreasing inclination angle of the trommel and decreasing rotational speed. A physical characterization of the university solid waste has been performed with a 20-kg sample of the tested waste. It was found that there is a trend of decreasing recovery of batteries with increasing paper composition, and a trend of increasing recovery of batteries with increasing organic materials composition.

Analysis of Experimental Research on Cyclones with Cylindrical and Spiral Shells

Directory of Open Access Journals (Sweden)

Aleksandras Chlebnikovas

2012-12-01

Full Text Available The conducted investigation is aimed at providing information on air flow parameters in the cylindrical and spiral shell (devices are designed for separating solid particles from air flow having tangent flow inlet. Experimental research has employed multi-cyclones created by the Department of Environmental Protection at Vilnius Gediminas Technical University. The study is focused on investigating and comparing the distribution of the dynamic pressure of the airflow in six-channel cyclones inside the structures of devices. The paper establishes and estimates the efficiency of air cleaning changing air phase parameters using different particulate matters. The efficiency of the cyclone has been defined applying the weighted method based on LAND 28-98/M-08 methodology. The article presents the results of experimental research on the air cleaning efficiency of cylindrical and spiral shells using 20 µm glass and clay particulate matter under the initial concentration that may vary from 500 mg/m3 to 15 g/m3 using semi-rings with windows at different positions. The obtained results has shown that the maximum efficiency of the cylindrical shell increases up to 87,3 % while the initial concentration of glass makes 15 g/m3.Article in Lithuanian

Solid Loss of Carrots During Simulated Gastric Digestion.

Science.gov (United States)

Kong, Fanbin; Singh, R Paul

2011-03-01

The knowledge of solid loss kinetics of foods during digestion is crucial for understanding the factors that constrain the release of nutrients from the food matrix and their fate of digestion. The objective of this study was to investigate the solid loss of carrots during simulated gastric digestion as affected by pH, temperature, viscosity of gastric fluids, mechanical force present in stomach, and cooking. Cylindrical carrot samples were tested by static soaking method and using a model stomach system. The weight retention, moisture, and loss of dry mass were determined. The results indicated that acid hydrolysis is critical for an efficient mass transfer and carrot digestion. Internal resistance rather than external resistance is dominant in the transfer of soluble solids from carrot to gastric fluid. Increase in viscosity of gastric fluid by adding 0.5% gum (w/w) significantly increased the external resistance and decreased mass transfer rate of carrots in static soaking. When mechanical force was not present, 61% of the solids in the raw carrot samples were released into gastric fluid after 4 h of static soaking in simulated gastric juice. Mechanical force significantly increased solid loss by causing surface erosion. Boiling increased the disintegration of carrot during digestion that may favor the loss of solids meanwhile reducing the amount of solids available for loss in gastric juice. Weibull function was successfully used to describe the solid loss of carrot during simulated digestion. The effective diffusion coefficients of solids were calculated using the Fick's second law of diffusion for an infinite cylinder, which are between 0.75 × 10(-11) and 8.72 × 10(-11) m(2)/s, depending on the pH of the gastric fluid.

Solid-solid phase transitions in Fe nanowires induced by axial strain

International Nuclear Information System (INIS)

Sandoval, Luis; Urbassek, Herbert M

2009-01-01

By means of classical molecular-dynamics simulations we investigate the solid-solid phase transition from a bcc to a close-packed crystal structure in cylindrical iron nanowires, induced by axial strain. The interatomic potential employed has been shown to be capable of describing the martensite-austenite phase transition in iron. We study the stress versus strain curves for different temperatures and show that for a range of temperatures it is possible to induce a solid-solid phase transition by axial strain before the elasticity is lost; these transition temperatures are below the bulk transition temperature. The two phases have different (non-linear) elastic behavior: the bcc phase softens, while the close-packed phase stiffens with temperature. We also consider the reversibility of the transformation in the elastic regimes, and the role of the strain rate on the critical strain necessary for phase transition.

Fast acquisition of multidimensional NMR spectra of solids and mesophases using alternative sampling methods.

Science.gov (United States)

Lesot, Philippe; Kazimierczuk, Krzysztof; Trébosc, Julien; Amoureux, Jean-Paul; Lafon, Olivier

2015-11-01

Unique information about the atom-level structure and dynamics of solids and mesophases can be obtained by the use of multidimensional nuclear magnetic resonance (NMR) experiments. Nevertheless, the acquisition of these experiments often requires long acquisition times. We review here alternative sampling methods, which have been proposed to circumvent this issue in the case of solids and mesophases. Compared to the spectra of solutions, those of solids and mesophases present some specificities because they usually display lower signal-to-noise ratios, non-Lorentzian line shapes, lower spectral resolutions and wider spectral widths. We highlight herein the advantages and limitations of these alternative sampling methods. A first route to accelerate the acquisition time of multidimensional NMR spectra consists in the use of sparse sampling schemes, such as truncated, radial or random sampling ones. These sparsely sampled datasets are generally processed by reconstruction methods differing from the Discrete Fourier Transform (DFT). A host of non-DFT methods have been applied for solids and mesophases, including the G-matrix Fourier transform, the linear least-square procedures, the covariance transform, the maximum entropy and the compressed sensing. A second class of alternative sampling consists in departing from the Jeener paradigm for multidimensional NMR experiments. These non-Jeener methods include Hadamard spectroscopy as well as spatial or orientational encoding of the evolution frequencies. The increasing number of high field NMR magnets and the development of techniques to enhance NMR sensitivity will contribute to widen the use of these alternative sampling methods for the study of solids and mesophases in the coming years. Copyright © 2015 John Wiley & Sons, Ltd.

Derivative Geometric Modeling of Basic Rotational Solids on CATIA

Institute of Scientific and Technical Information of China (English)

MENG Xiang-bao; PAN Zi-jian; ZHU Yu-xiang; LI Jun

2011-01-01

Hybrid models derived from rotational solids like cylinders, cones and spheres were implemented on CATIA software. Firstly, make the isosceles triangular prism, cuboid, cylinder, cone, sphere, and the prism with tangent conic and curved triangle ends, the cuboid with tangent cylindrical and curved rectangle ends, the cylinder with tangent spherical and curved circular ends as the basic Boolean deference units to the primary cylinders, cones and spheres on symmetrical and some critical geometric conditions, forming a series of variant solid models. Secondly, make the deference units above as the basic union units to the main cylinders, cones, and spheres accordingly, forming another set of solid models. Thirdly, make the tangent ends of union units into oblique conic, cylindrical, or with revolved triangular pyramid, quarterly cylinder and annulus ends on sketch based features to the main cylinders, cones, and spheres repeatedly, thus forming still another set of solid models. It is expected that these derivative models be beneficial both in the structure design, hybrid modeling, and finite element analysis of engineering components and in comprehensive training of spatial configuration of engineering graphics.

Cylindrical fabric-confined soil structures

Science.gov (United States)

Harrison, Richard A.

A cylindrical fabric-soil structural concept for implementation on the moon and Mars which provides many advantages is proposed. The most efficient use of fabric is to fashion it into cylindrical tubes, creating cylindrical fabric-confined soil structures. The length, diameter, and curvature of the tubes will depend on the intended application. The cylindrical hoop forces provide radial confinement while end caps provide axial confinement. One of the ends is designed to allow passage of the soil into the fabric tube before sealing. Transportation requirements are reduced due to the low mass and volume of the fabric. Construction requirements are reduced due to the self-erection capability via the pneumatic exoskeleton. Maintenance requirements are reduced due to the passive nature of the concept. The structure's natural ductility is well suited for any seismic activity.

A semi-empirical approach to analyze the activities of cylindrical radioactive samples using gamma energies from 185 to 1764 keV.

Science.gov (United States)

Huy, Ngo Quang; Binh, Do Quang

2014-12-01

This work suggests a method for determining the activities of cylindrical radioactive samples. The self-attenuation factor was applied for providing the self-absorption correction of gamma rays in the sample material. The experimental measurement of a (238)U reference sample and the calculation using the MCNP5 code allow obtaining the semi-empirical formulae of detecting efficiencies for the gamma energies ranged from 185 to 1764keV. These formulae were used to determine the activities of the (238)U, (226)Ra, (232)Th, (137)Cs and (40)K nuclides in the IAEA RGU-1, IAEA-434, IAEA RGTh-1, IAEA-152 and IAEA RGK-1 radioactive standards. The coincidence summing corrections for gamma rays in the (238)U and (232)Th series were applied. The activities obtained in this work were in good agreement with the reference values. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Pulsed Cylindrical Magnetron for Deposition

Science.gov (United States)

Korenev, Sergey

2012-10-01

The magnetron sputtering deposition of films and coatings broadly uses in microelectronics, material science, environmental applications and etc. The rate of target evaporation and time for deposition of films and coatings depends on magnetic field. These parameters link with efficiency of gas molecules ionization by electrons. The cylindrical magnetrons use for deposition of films and coatings on inside of pipes for different protective films and coatings in oil, chemical, environmental applications. The classical forming of magnetic field by permanent magnets or coils for big and long cylindrical magnetrons is complicated. The new concept of pulsed cylindrical magnetron for high rate deposition of films and coating for big and long pipes is presented in this paper. The proposed cylindrical magnetron has azimuthally pulsed high magnetic field, which allows forming the high ionized plasma and receiving high rate of evaporation material of target (central electrode). The structure of proposed pulsed cylindrical magnetron sputtering system is given. The main requirements to deposition system are presented. The preliminary data for forming of plasma and deposition of Ta films and coatings on the metal pipers are discussed. The comparison of classical and proposed cylindrical magnetrons is given. The analysis of potential applications is considered.

Modified emission-transmission method for determining trace elements in solid samples using the XRF techniques

International Nuclear Information System (INIS)

Poblete, V.; Alvarez, M.; Hermosilla, M.

2000-01-01

This is a study of an analysis of trace elements in medium thick solid samples, by the modified transmission emission method, using the energy dispersion X-ray fluorescence technique (EDXRF). The effects of absorption and reinforcement are the main disadvantages of the EDXRF technique for the quantitative analysis of bigger elements and trace elements in solid samples. The implementation of this method and its application to a variety of samples was carried out using an infinitely thick multi-element white sample that calculates the correction factors by absorbing all the analytes in the sample. The discontinuities in the masic absorption coefficients versus energies association for each element, with medium thick and homogenous samples, are analyzed and corrected. A thorough analysis of the different theoretical and test variables are proven by using real samples, including certified material with known concentration. The simplicity of the calculation method and the results obtained show the method's major precision, with possibilities for the non-destructive routine analysis of different solid samples, using the EDXRF technique (author)

Solid Sampling with a Diode Laser for Portable Ambient Mass Spectrometry.

Science.gov (United States)

Yung, Yeni P; Wickramasinghe, Raveendra; Vaikkinen, Anu; Kauppila, Tiina J; Veryovkin, Igor V; Hanley, Luke

2017-07-18

A hand-held diode laser is implemented for solid sampling in portable ambient mass spectrometry (MS). Specifically, a pseudocontinuous wave battery-powered surgical laser diode is employed for portable laser diode thermal desorption (LDTD) at 940 nm and compared with nanosecond pulsed laser ablation at 2940 nm. Postionization is achieved in both cases using atmospheric pressure photoionization (APPI). The laser ablation atmospheric pressure photoionization (LAAPPI) and LDTD-APPI mass spectra of sage leaves (Salvia officinalis) using a field-deployable quadrupole ion trap MS display many similar ion peaks, as do the mass spectra of membrane grown biofilms of Pseudomonas aeruginosa. These results indicate that LDTD-APPI method should be useful for in-field sampling of plant and microbial communities, for example, by portable ambient MS. The feasibility of many portable MS applications is facilitated by the availability of relatively low cost, portable, battery-powered diode lasers. LDTD could also be coupled with plasma- or electrospray-based ionization for the analysis of a variety of solid samples.

Numerical study of interfacial flows with immersed solids

International Nuclear Information System (INIS)

Kim, Sung Il; Son, Gi Hun

2003-01-01

A numerical method is presented for computing unsteady incompressible two-phase flows with immersed solids. The method is based on a level set technique for capturing the phase interface, which is modified to satisfy a contact angle condition at the solid-fluid interface as well as to achieve mass conservation during the whole calculation procedure. The modified level set method is applied for numerical simulation of bubble deformation in a micro channel with a cylindrical solid block and liquid jet from a micro nozzle

Cylindrical-shaped nanotube field effect transistor

KAUST Repository

Hussain, Muhammad Mustafa; Fahad, Hossain M.; Smith, Casey E.; Rojas, Jhonathan Prieto

2015-01-01

A cylindrical-shaped nanotube FET may be manufactured on silicon (Si) substrates as a ring etched into a gate stack and filled with semiconductor material. An inner gate electrode couples to a region of the gate stack inside the inner circumference of the ring. An outer gate electrode couples to a region of the gate stack outside the outer circumference of the ring. The multi-gate cylindrical-shaped nanotube FET operates in volume inversion for ring widths below 15 nanometers. The cylindrical-shaped nanotube FET demonstrates better short channel effect (SCE) mitigation and higher performance (I.sub.on/I.sub.off) than conventional transistor devices. The cylindrical-shaped nanotube FET may also be manufactured with higher yields and cheaper costs than conventional transistors.

Cylindrical-shaped nanotube field effect transistor

KAUST Repository

Hussain, Muhammad Mustafa

2015-12-29

A cylindrical-shaped nanotube FET may be manufactured on silicon (Si) substrates as a ring etched into a gate stack and filled with semiconductor material. An inner gate electrode couples to a region of the gate stack inside the inner circumference of the ring. An outer gate electrode couples to a region of the gate stack outside the outer circumference of the ring. The multi-gate cylindrical-shaped nanotube FET operates in volume inversion for ring widths below 15 nanometers. The cylindrical-shaped nanotube FET demonstrates better short channel effect (SCE) mitigation and higher performance (I.sub.on/I.sub.off) than conventional transistor devices. The cylindrical-shaped nanotube FET may also be manufactured with higher yields and cheaper costs than conventional transistors.

Air sampling with solid phase microextraction

Science.gov (United States)

Martos, Perry Anthony

There is an increasing need for simple yet accurate air sampling methods. The acceptance of new air sampling methods requires compatibility with conventional chromatographic equipment, and the new methods have to be environmentally friendly, simple to use, yet with equal, or better, detection limits, accuracy and precision than standard methods. Solid phase microextraction (SPME) satisfies the conditions for new air sampling methods. Analyte detection limits, accuracy and precision of analysis with SPME are typically better than with any conventional air sampling methods. Yet, air sampling with SPME requires no pumps, solvents, is re-usable, extremely simple to use, is completely compatible with current chromatographic equipment, and requires a small capital investment. The first SPME fiber coating used in this study was poly(dimethylsiloxane) (PDMS), a hydrophobic liquid film, to sample a large range of airborne hydrocarbons such as benzene and octane. Quantification without an external calibration procedure is possible with this coating. Well understood are the physical and chemical properties of this coating, which are quite similar to those of the siloxane stationary phase used in capillary columns. The log of analyte distribution coefficients for PDMS are linearly related to chromatographic retention indices and to the inverse of temperature. Therefore, the actual chromatogram from the analysis of the PDMS air sampler will yield the calibration parameters which are used to quantify unknown airborne analyte concentrations (ppb v to ppm v range). The second fiber coating used in this study was PDMS/divinyl benzene (PDMS/DVB) onto which o-(2,3,4,5,6- pentafluorobenzyl) hydroxylamine (PFBHA) was adsorbed for the on-fiber derivatization of gaseous formaldehyde (ppb v range), with and without external calibration. The oxime formed from the reaction can be detected with conventional gas chromatographic detectors. Typical grab sampling times were as small as 5 seconds

The electrostatic cylindrical sheath in a plasma

International Nuclear Information System (INIS)

Wang Chunhua; Sun Xiaoxia; Bai Dongxue

2004-01-01

The electrostatic sheath with a cylindrical geometry in an ion-electron plasma is investigated. Assuming a Boltzmann response to electrons and cold ions with bulk flow, it is shown that the radius of the cylindrical geometry do not affect the sheath potential significantly. The authors also found that the sheath potential profile is steeper in the cylindrical sheath compared to the slab sheath. The distinct feature of the cylindrical sheath is that the ion density distribution is not monotonous. The sheath region can be divided into three regions, two ascendant regions and one descendant region. (author)

Homotheties of cylindrically symmetric static spacetimes

International Nuclear Information System (INIS)

Qadir, A.; Ziad, M.; Sharif, M.

1998-08-01

In this note we consider the homotheties of cylindrically symmetric static spacetimes. We find that we can provide a complete list of all metrics that admit non-trivial homothetic motions and are cylindrically symmetric static. (author)

Forced Vibration Analysis for a FGPM Cylindrical Shell

Directory of Open Access Journals (Sweden)

Hong-Liang Dai

2013-01-01

Full Text Available This article presents an analytical study for forced vibration of a cylindrical shell which is composed of a functionally graded piezoelectric material (FGPM. The cylindrical shell is assumed to have two-constituent material distributions through the thickness of the structure, and material properties of the cylindrical shell are assumed to vary according to a power-law distribution in terms of the volume fractions for constituent materials, the exact solution for the forced vibration problem is presented. Numerical results are presented to show the effect of electric excitation, thermal load, mechanical load and volume exponent on the static and force vibration of the FGPM cylindrical shell. The goal of this investigation is to optimize the FGPM cylindrical shell in engineering, also the present solution can be used in the forced vibration analysis of cylindrical smart elements.

Attenuation correction factors for cylindrical, disc and box geometry

International Nuclear Information System (INIS)

Agarwal, Chhavi; Poi, Sanhita; Mhatre, Amol; Goswami, A.; Gathibandhe, M.

2009-01-01

In the present study, attenuation correction factors have been experimentally determined for samples having cylindrical, disc and box geometry and compared with the attenuation correction factors calculated by Hybrid Monte Carlo (HMC) method [ C. Agarwal, S. Poi, A. Goswami, M. Gathibandhe, R.A. Agrawal, Nucl. Instr. and. Meth. A 597 (2008) 198] and with the near-field and far-field formulations available in literature. It has been observed that the near-field formulae, although said to be applicable at close sample-detector geometry, does not work at very close sample-detector configuration. The advantage of the HMC method is that it is found to be valid for all sample-detector geometries.

Sample-size effects in fast-neutron gamma-ray production measurements: solid-cylinder samples

International Nuclear Information System (INIS)

Smith, D.L.

1975-09-01

The effects of geometry, absorption and multiple scattering in (n,Xγ) reaction measurements with solid-cylinder samples are investigated. Both analytical and Monte-Carlo methods are employed in the analysis. Geometric effects are shown to be relatively insignificant except in definition of the scattering angles. However, absorption and multiple-scattering effects are quite important; accurate microscopic differential cross sections can be extracted from experimental data only after a careful determination of corrections for these processes. The results of measurements performed using several natural iron samples (covering a wide range of sizes) confirm validity of the correction procedures described herein. It is concluded that these procedures are reliable whenever sufficiently accurate neutron and photon cross section and angular distribution information is available for the analysis. (13 figures, 5 tables) (auth)

Preparation of water-equivalent radioactive solid sources

International Nuclear Information System (INIS)

Yamazaki, Ione M.; Koskinas, Marina F.; Dias, Mauro S.

2011-01-01

The development of water-equivalent solid sources in two geometries, cylindrical and flat without the need of irradiation in a strong gamma radiation source to obtain polymerization is described. These sources should have density similar to water and good uniformity. Therefore, the density and uniformity of the distribution of radioactive material in the resins were measured. The variation of these parameters in the cylindrical geometry was better than 2.0% for the density and 2.3% for the uniformity and for the flat geometry the values obtained were better than 2.0 % and better than 1.3%, respectively. These values are in good agreement with the literature. (author)

Eosinophilia in routine blood samples as a biomarker for solid tumor development

DEFF Research Database (Denmark)

Andersen, Christen Bertel L; Siersma, V.D.; Hasselbalch, H.C.

2014-01-01

eosinophilia in routine blood samples as a potential biomarker of solid tumor development in a prospective design. MATERIAL AND METHODS: From the Copenhagen Primary Care Differential Count (CopDiff) Database, we identified 356 196 individuals with at least one differential cell count (DIFF) encompassing...... was increased with mild eosinophilia [OR 1.93 (CI 1.29-2.89), p = 0.0013]. No associations with eosinophilia were observed for the remaining solid cancers. CONCLUSION: We demonstrate that eosinophilia in routine blood samples associates with an increased risk of bladder cancer. Our data emphasize...... that additional preclinical studies are needed in order to shed further light on the role of eosinophils in carcinogenesis, where it is still unknown whether the cells contribute to tumor immune surveillance or neoplastic evolution....

Solid-phase extraction and determination of trace elements in environmental samples using naphthalene adsorbent

International Nuclear Information System (INIS)

Pourreza, N.

2004-01-01

Naphthalene co-precipitated with quaternary ammonium salt such as tetraoctyl ammonium bromide and methyltrioctyl ammonium chloride have been used as adsorbent for solid phase extraction of metal ions such as Hg, Cd and Fe. The metal ions are retained on the adsorbent in a column as their complexes with suitable ligands and eluted by an eluent before instrumental measurements. The optimization of the procedures for solid phase extraction and consequent determination of trace elements and application to environmental samples especially water samples will be discussed. (author)

15N and 31P solid-state NMR study of transmembrane domain alignment of M2 protein of influenza A virus in hydrated cylindrical lipid bilayers confined to anodic aluminum oxide nanopores.

Science.gov (United States)

Chekmenev, Eduard Y; Hu, Jun; Gor'kov, Peter L; Brey, William W; Cross, Timothy A; Ruuge, Andres; Smirnov, Alex I

2005-04-01

This communication reports the first example of a high resolution solid-state 15N 2D PISEMA NMR spectrum of a transmembrane peptide aligned using hydrated cylindrical lipid bilayers formed inside nanoporous anodic aluminum oxide (AAO) substrates. The transmembrane domain SSDPLVVA(A-15N)SIIGILHLILWILDRL of M2 protein from influenza A virus was reconstituted in hydrated 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine bilayers that were macroscopically aligned by a conventional micro slide glass support or by the AAO nanoporous substrate. 15N and 31P NMR spectra demonstrate that both the phospholipids and the protein transmembrane domain are uniformly aligned in the nanopores. Importantly, nanoporous AAO substrates may offer several advantages for membrane protein alignment in solid-state NMR studies compared to conventional methods. Specifically, higher thermal conductivity of aluminum oxide is expected to suppress thermal gradients associated with inhomogeneous radio frequency heating. Another important advantage of the nanoporous AAO substrate is its excellent accessibility to the bilayer surface for exposure to solute molecules. Such high accessibility achieved through the substrate nanochannel network could facilitate a wide range of structure-function studies of membrane proteins by solid-state NMR.

Metal-organic framework based in-syringe solid-phase extraction for the on-site sampling of polycyclic aromatic hydrocarbons from environmental water samples.

Science.gov (United States)

Zhang, Xiaoqiong; Wang, Peiyi; Han, Qiang; Li, Hengzhen; Wang, Tong; Ding, Mingyu

2018-04-01

In-syringe solid-phase extraction is a promising sample pretreatment method for the on-site sampling of water samples because of its outstanding advantages of portability, simple operation, short extraction time, and low cost. In this work, a novel in-syringe solid-phase extraction device using metal-organic frameworks as the adsorbent was fabricated for the on-site sampling of polycyclic aromatic hydrocarbons from environmental waters. Trace polycyclic aromatic hydrocarbons were effectively extracted through the self-made device followed by gas chromatography with mass spectrometry analysis. Owing to the excellent adsorption performance of metal-organic frameworks, the analytes could be completely adsorbed during one adsorption cycle, thus effectively shortening the extraction time. Moreover, the adsorbed analytes could remain stable on the device for at least 7 days, revealing the potential of the self-made device for on-site sampling of degradable compounds in remote regions. The limit of detection ranged from 0.20 to 1.9 ng/L under the optimum conditions. Satisfactory recoveries varying from 84.4 to 104.5% and relative standard deviations below 9.7% were obtained in real samples analysis. The results of this study promote the application of metal-organic frameworks in sample preparation and demonstrate the great potential of in-syringe solid-phase extraction for the on-site sampling of trace contaminants in environmental waters. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Determination of element concentrations in biological reference materials by solid sampling and other analytical methods

International Nuclear Information System (INIS)

Schauenburg, H.; Weigert, P.

1992-01-01

Using solid sampling with graphite furnace atomic absorption spectrometry (GFAAS), values for cadmium, copper, lead and zinc in six biological reference materials were obtained from up to four laboratories participating in three collaborative studies. These results are compared with those obtained with other methods used in routine analysis from laboratories of official food control. Under certain conditions solid sampling with GFAAS seems to be suitable for routine analysis as well as conventional methods. (orig.)

Magnetostatic interactions and forces between cylindrical permanent magnets

International Nuclear Information System (INIS)

Vokoun, David; Beleggia, Marco; Heller, Ludek; Sittner, Petr

2009-01-01

Permanent magnets of various shapes are often utilized in magnetic actuators, sensors or releasable magnetic fasteners. Knowledge of the magnetic force is required to control devices reliably. Here, we introduce an analytical expression for calculating the attraction force between two cylindrical permanent magnets on the assumption of uniform magnetization. Although the assumption is not fulfilled exactly in cylindrical magnets, we obtain a very good agreement between the calculated and measured forces between two identical cylindrical magnets and within an array of NdFeB cylindrical magnets.

Verification of Compton scattering spectrum of a 662 keV photon beam scattered on a cylindrical steel target using MCNP5 code

International Nuclear Information System (INIS)

Thanh, Tran Thien; Nguyen, Vo Hoang; Chuong, Huynh Dinh; Tran, Le Bao; Tam, Hoang Duc; Binh, Nguyen Thi; Tao, Chau Van

2015-01-01

This article focuses on the possible application of a "1"3"7Cs low-radioactive source (5 mCi) and a NaI(Tl) detector for measuring the saturation thickness of solid cylindrical steel targets. In order to increase the reliability of the obtained experimental results and to verify the detector response function of Compton scattering spectrum, simulation using Monte Carlo N-particle (MCNP5) code is performed. The obtained results are in good agreement with the response functions of the simulation scattering and experimental scattering spectra. On the basis of such spectra, the saturation depth of a steel cylinder is determined by experiment and simulation at about 27 mm using gamma energy of 662 keV ("1"3"7Cs) at a scattering angle of 120°. This study aims at measuring the diameter of solid cylindrical objects by gamma-scattering technique. - Highlights: • This study aims a possible application a "1"3"7Cs low-radioactive source (5 mCi) and a NaI(Tl) detector for measuring the saturation thickness of solid cylindrical steel targets by gamma-scattering technique. • Monte Carlo N-particle (MCNP5) code is performed to verify on the detector response function of Compton scattering spectrum. • The results show a good agreement in response function of the experimental and simulation scattering spectra. • The saturation depth of a steel cylinder is determined by experiment and simulation at about 27 mm using gamma energy of 662 keV ("1"3"7Cs) at a scattering angle of 120°.

Sampling of solid particles in clouds

International Nuclear Information System (INIS)

Feuillebois, F.; Lasek, A.; Scibilia, M.F.

1986-01-01

This paper is concerned with the sampling of small solid particles from clouds by an airborne apparatus to be mounted on an airplane for meteorological investigations. In the airborne experiment the particles entering the test tube should be as representative as possible of the upstream conditions ahead of the plane, in the real cloud. Due to the inertia of the particles, the proportion of the different sizes of particles entering the test tube depends on the location of the tube mouth. We present a method of calculating the real concentration in particles of different sizes, using the results of measurements executed during the flight of an airplane in a cloud. Two geometries are considered: the nose of the airplane, represented schematically by a hemisphere, and a wing represented by a (2D) Joukowski profile which matches well a NACA 0015 profile on its leading edge

Sound radiation modes of cylindrical surfaces and their application to vibro-acoustics analysis of cylindrical shells

Science.gov (United States)

Sun, Yao; Yang, Tiejun; Chen, Yuehua

2018-06-01

In this paper, sound radiation modes of baffled cylinders have been derived by constructing the radiation resistance matrix analytically. By examining the characteristics of sound radiation modes, it is found that radiation coefficient of each radiation mode increases gradually with the increase of frequency while modal shapes of sound radiation modes of cylindrical shells show a weak dependence upon frequency. Based on understandings on sound radiation modes, vibro-acoustics behaviors of cylindrical shells have been analyzed. The vibration responses of cylindrical shells are described by modified Fourier series expansions and solved by Rayleigh-Ritz method involving Flügge shell theory. Then radiation efficiency of a resonance has been determined by examining whether the vibration pattern is in correspondence with a sound radiation mode possessing great radiation efficiency. Furthermore, effects of thickness and boundary conditions on sound radiation of cylindrical shells have been investigated. It is found that radiation efficiency of thicker shells is greater than thinner shells while shells with a clamped boundary constraint radiate sound more efficiently than simply supported shells under thin shell assumption.

A cylindrical drift chamber for radiative muon capture experiments at TRIUMF

International Nuclear Information System (INIS)

Henderson, R.S.; Dawson, R.J.; Azuelos, G.; Robertson, B.C.; Hasinoff, M.D.; Ahamad, S.; Gorringe, T.P.; Serna-Angel, A.; Blecher, M.; Wright, D.H.

1990-01-01

In the Standard Model, the weak interaction is purely V-A in character. However in semileptonic reactions the strong force induces additional couplings. Radiative muon capture (RMC), μ - Z → ν(Z-1)γ, is a process which is particularly sensitive to the induced pseudoscalar coupling constant, g p , which is still very poorly determined experimentally. Due to the extremely small branching ratio (∼ 6 x 10 -8 ), the elementary reaction μ - p → νnγ has never been measured. Effort to date has concentrated on nuclear RMC where the branching ratio is much larger, but the interpretation of these results is hindered by nuclear structure uncertainties. A measurement is being carried out at TRIUMF to determine the rate of RMC on hydrogen to a precision of 8% leading to a determination of g p with an error of 10%. The detection system is based on a large volume cylindrical drift chamber, in an axial magnetic field, acting as an e + e - pair spectrometer with a solid angle of ≅ 2 π. The design, construction and performance of the cylindrical drift chamber are discussed

Space Charge Effect in the Sheet and Solid Electron Beam

Science.gov (United States)

Song, Ho Young; Kim, Hyoung Suk; Ahn, Saeyoung

1998-11-01

We analyze the space charge effect of two different types of electron beam ; sheet and solid electron beam. Electron gun simulations are carried out using shadow and control grids for high and low perveance. Rectangular and cylindrical geometries are used for sheet and solid electron beam in planar and disk type cathode. The E-gun code is used to study the limiting current and space charge loading in each geometries.

Hypercrosslinked particles for the extraction of sweeteners using dispersive solid-phase extraction from environmental samples.

Science.gov (United States)

Lakade, Sameer S; Zhou, Qing; Li, Aimin; Borrull, Francesc; Fontanals, Núria; Marcé, Rosa M

2018-04-01

This work presents a new extraction material, namely, Q-100, based on hypercrosslinked magnetic particles, which was tested in dispersive solid-phase extraction for a group of sweeteners from environmental samples. The hypercrosslinked Q-100 magnetic particles had the advantage of suitable pore size distribution and high surface area, and showed good retention behavior toward sweeteners. Different dispersive solid-phase extraction parameters such as amount of magnetic particles or extraction time were optimized. Under optimum conditions, Q-100 showed suitable apparent recovery, ranging in the case of river water sample from 21 to 88% for all the sweeteners, except for alitame (12%). The validated method based on dispersive solid-phase extraction using Q-100 followed by liquid chromatography with tandem mass spectrometry provided good linearity and limits of quantification between 0.01 and 0.1 μg/L. The method was applied to analyze samples from river water and effluent wastewater, and four sweeteners (acesulfame, saccharin, cyclamate, and sucralose) were found in both types of sample. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Optimization of Cylindrical Hall Thrusters

International Nuclear Information System (INIS)

Raitses, Yevgeny; Smirnov, Artem; Granstedt, Erik; Fisch, Nathaniel J.

2007-01-01

The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation.

Optimization of Cylindrical Hall Thrusters

International Nuclear Information System (INIS)

Raitses, Yevgeny; Smirnov, Artem; Granstedt, Erik; Fi, Nathaniel J.

2007-01-01

The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation

Analytical solution for the transient wave propagation of a buried cylindrical P-wave line source in a semi-infinite elastic medium with a fluid surface layer

Science.gov (United States)

Shan, Zhendong; Ling, Daosheng

2018-02-01

This article develops an analytical solution for the transient wave propagation of a cylindrical P-wave line source in a semi-infinite elastic solid with a fluid layer. The analytical solution is presented in a simple closed form in which each term represents a transient physical wave. The Scholte equation is derived, through which the Scholte wave velocity can be determined. The Scholte wave is the wave that propagates along the interface between the fluid and solid. To develop the analytical solution, the wave fields in the fluid and solid are defined, their analytical solutions in the Laplace domain are derived using the boundary and interface conditions, and the solutions are then decomposed into series form according to the power series expansion method. Each item of the series solution has a clear physical meaning and represents a transient wave path. Finally, by applying Cagniard's method and the convolution theorem, the analytical solutions are transformed into the time domain. Numerical examples are provided to illustrate some interesting features in the fluid layer, the interface and the semi-infinite solid. When the P-wave velocity in the fluid is higher than that in the solid, two head waves in the solid, one head wave in the fluid and a Scholte wave at the interface are observed for the cylindrical P-wave line source.

Determination of total mercury for marine environmental monitoring studies by solid sampling continuum source high resolution atomic absorption spectrometry

Energy Technology Data Exchange (ETDEWEB)

Mandjukov, Petko; Orani, Anna Maria; Han, Eunmi; Vassileva, Emilia, E-mail: e.vasileva-veleva@iaea.org

2015-01-01

The most critical step in almost all commonly used analytical procedures for Hg determination is the sample preparation due to its extreme volatility. One of the possible solutions of this problem is the application of methods for direct analysis of solid samples. The possibilities for solid sampling high resolution continuum source atomic absorption spectrometry (HR CS AAS) determination of total mercury in various marine environmental samples e.g. sediments and biota are object of the present study. The instrumental parameters were optimized in order to obtain reproducible and interference free analytical signal. A calibration technique based on the use of solid standard certified reference materials similar to the nature of the analyzed sample was developed and applied to various CRMs and real samples. This technique allows simple and reliable evaluation of the uncertainty of the result and the metrological characteristics of the method. A validation approach in line with the requirements of ISO 17025 standard and Eurachem guidelines was followed. With this in mind, selectivity, working range (0.06 to 25 ng for biota and 0.025 to 4 ng for sediment samples, expressed as total Hg) linearity (confirmed by Student's t-test), bias (1.6–4.3%), repeatability (4–9%), reproducibility (9–11%), and absolute limit of detection (0.025 ng for sediment, 0.096 ng for marine biota) were systematically assessed using solid CRMs. The relative expanded uncertainty was estimated at 15% for sediment sample and 8.5% for marine biota sample (k = 2). Demonstration of traceability of measurement results is also presented. The potential of the proposed analytical procedure, based on solid sampling HR CS AAS technique was demonstrated by direct analysis of sea sediments form the Caribbean region and various CRMs. Overall, the use of solid sampling HR CS AAS permits obtaining significant advantages for the determination of this complex analyte in marine samples, such as

Solid polymer electrolyte composite membrane comprising a porous support and a solid polymer electrolyte including a dispersed reduced noble metal or noble metal oxide

Science.gov (United States)

Liu, Han; Mittelsteadt, Cortney K; Norman, Timothy J; Griffith, Arthur E; LaConti, Anthony B

2015-02-24

A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a thin, rigid, dimensionally-stable, non-electrically-conducting support, the support having a plurality of cylindrical, straight-through pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores are unevenly distributed, with some or no pores located along the periphery and more pores located centrally. The pores are completely filled with a solid polymer electrolyte, the solid polymer electrolyte including a dispersed reduced noble metal or noble metal oxide. The solid polymer electrolyte may also be deposited over the top and/or bottom surfaces of the support.

Synchrotron X-ray measurement techniques for thermal barrier coated cylindrical samples under thermal gradients

Energy Technology Data Exchange (ETDEWEB)

Siddiqui, Sanna F.; Knipe, Kevin; Manero, Albert; Raghavan, Seetha [Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Meid, Carla; Wischek, Janine; Bartsch, Marion [German Aerospace Center (DLR), Institute of Materials Research, 51147 Cologne (Germany); Okasinski, John; Almer, Jonathan [X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Karlsson, Anette M. [Cleveland State University, 2121 Euclid Avenue, Cleveland, Ohio 44115 (United States)

2013-08-15

Measurement techniques to obtain accurate in situ synchrotron strain measurements of thermal barrier coating systems (TBCs) applied to hollow cylindrical specimens are presented in this work. The Electron Beam Physical Vapor Deposition coated specimens with internal cooling were designed to achieve realistic temperature gradients over the TBC coated material such as that occurring in the turbine blades of aeroengines. Effects of the circular cross section on the x-ray diffraction (XRD) measurements in the various layers, including the thermally grown oxide, are investigated using high-energy synchrotron x-rays. Multiple approaches for beam penetration including collection, tangential, and normal to the layers, along with variations in collection parameters are compared for their ability to attain high-resolution XRD data from the internal layers. This study displays the ability to monitor in situ, the response of the internal layers within the TBC, while implementing a thermal gradient across the thickness of the coated sample. The thermal setup maintained coating surface temperatures in the range of operating conditions, while monitoring the substrate cooling, for a controlled thermal gradient. Through variation in measurement location and beam parameters, sufficient intensities are obtained from the internal layers which can be used for depth resolved strain measurements. Results are used to establish the various techniques for obtaining XRD measurements through multi-layered coating systems and their outcomes will pave the way towards goals in achieving realistic in situ testing of these coatings.

On isotropic cylindrically symmetric stellar models

International Nuclear Information System (INIS)

Nolan, Brien C; Nolan, Louise V

2004-01-01

We attempt to match the most general cylindrically symmetric vacuum spacetime with a Robertson-Walker interior. The matching conditions show that the interior must be dust filled and that the boundary must be comoving. Further, we show that the vacuum region must be polarized. Imposing the condition that there are no trapped cylinders on an initial time slice, we can apply a result of Thorne's and show that trapped cylinders never evolve. This results in a simplified line element which we prove to be incompatible with the dust interior. This result demonstrates the impossibility of the existence of an isotropic cylindrically symmetric star (or even a star which has a cylindrically symmetric portion). We investigate the problem from a different perspective by looking at the expansion scalars of invariant null geodesic congruences and, applying to the cylindrical case, the result that the product of the signs of the expansion scalars must be continuous across the boundary. The result may also be understood in relation to recent results about the impossibility of the static axially symmetric analogue of the Einstein-Straus model

Bio-Inspired Wide-Angle Broad-Spectrum Cylindrical Lens Based on Reflections from Micro-Mirror Array on a Cylindrical Elastomeric Membrane

Directory of Open Access Journals (Sweden)

Chi-Chieh Huang

2014-06-01

Full Text Available We present a wide-angle, broad-spectrum cylindrical lens based on reflections from an array of three-dimensional, high-aspect-ratio micro-mirrors fabricated on a cylindrical elastomeric substrate, functionally inspired by natural reflecting superposition compound eyes. Our device can perform one-dimensional focusing and beam-shaping comparable to conventional refraction-based cylindrical lenses, while avoiding chromatic aberration. The focal length of our cylindrical lens is 1.035 mm, suitable for micro-optical systems. Moreover, it demonstrates a wide field of view of 152° without distortion, as well as modest spherical aberrations. Our work could be applied to diverse applications including laser diode collimation, barcode scanning, holography, digital projection display, microlens arrays, and optical microscopy.

Material failure and inertial instabilities in a shocked imploded cylindrical aluminum sample

International Nuclear Information System (INIS)

Chandler, E.A.; Egan, P.; Stokes, J.

1998-01-01

The authors have used the LANL Pegasus Z-pinch facility to drive a thin cylindrically-convergent Al liner to ∼3 km/s to launch ∼30 GPa shocks in a 3-mm thick 10-mm-i.d. aluminum cylinder whose interior is filled with 1 atm Xe gas. The subsequent material motion of the metal and gas is diagnosed with both radial and axial flash x-rays and with optical framing cameras. Instabilities are seeded by implanting wires of assorted higher density metal parallel to the cylinder axis. The authors have done two shots, varying the target from Al 1100-O to Al 6061-T6 to explore the effect of changing material strength. The images show the spallation failure of the metal-gas interface on shock release and the effect of the seeded instabilities

Spiral modes in cold cylindrical systems

International Nuclear Information System (INIS)

Robe, H.

1975-01-01

The linearized hydrodynamical equations governing the non-axisymmetric free modes of oscillation of cold cylindrical stellar systems are separated in cylindrical coordinates and solved numerically for two models. Short-wavelength unstable modes corresponding to tight spirals do not exist; but there exists an unstable growing mode which has the form of trailing spirals which are quite open. (orig.) [de

Determination of total mercury for marine environmental monitoring studies by solid sampling continuum source high resolution atomic absorption spectrometry

Science.gov (United States)

Mandjukov, Petko; Orani, Anna Maria; Han, Eunmi; Vassileva, Emilia

2015-01-01

The most critical step in almost all commonly used analytical procedures for Hg determination is the sample preparation due to its extreme volatility. One of the possible solutions of this problem is the application of methods for direct analysis of solid samples. The possibilities for solid sampling high resolution continuum source atomic absorption spectrometry (HR CS AAS) determination of total mercury in various marine environmental samples e.g. sediments and biota are object of the present study. The instrumental parameters were optimized in order to obtain reproducible and interference free analytical signal. A calibration technique based on the use of solid standard certified reference materials similar to the nature of the analyzed sample was developed and applied to various CRMs and real samples. This technique allows simple and reliable evaluation of the uncertainty of the result and the metrological characteristics of the method. A validation approach in line with the requirements of ISO 17025 standard and Eurachem guidelines was followed. With this in mind, selectivity, working range (0.06 to 25 ng for biota and 0.025 to 4 ng for sediment samples, expressed as total Hg) linearity (confirmed by Student's t-test), bias (1.6-4.3%), repeatability (4-9%), reproducibility (9-11%), and absolute limit of detection (0.025 ng for sediment, 0.096 ng for marine biota) were systematically assessed using solid CRMs. The relative expanded uncertainty was estimated at 15% for sediment sample and 8.5% for marine biota sample (k = 2). Demonstration of traceability of measurement results is also presented. The potential of the proposed analytical procedure, based on solid sampling HR CS AAS technique was demonstrated by direct analysis of sea sediments form the Caribbean region and various CRMs. Overall, the use of solid sampling HR CS AAS permits obtaining significant advantages for the determination of this complex analyte in marine samples, such as straightforward

Neutron emission from impacted solid LiD samples

International Nuclear Information System (INIS)

Kaushik, T.C.; Shyam, A.; Kulkarni, L.V.; Srinivasan, M.

1993-01-01

Nylon projectiles with 0.1 g to 0.3 g mass, accelerated to velocities of 0.2-1 km/s using a 60 cm long electromagnetic accelerator (railgun), have been impacted upon solid lithium deuteride (LiD) samples of 3 proportional counters. The output from the BF 3 set-up is monitored in several ways to characterize the possible neutron emission from the target. This includes a simple technique of counting the single channel analyser (SCA) output through a dead-time unit to identify bursts of < 100 μs duration. Counting is started after a delay of ∼ 1 ms to avoid the initial interference from the capacitor bank discharge. The signal is also recorded in a storage oscilloscope from the start of projectile acceleration along with a time marker just before the impact. From a number of shots taken with and without the samples, a significant evidence of neutron emission from the LiD samples appears to emerge. The experiments suggest that approximately 100 neutrons might be generated during every such impact in a duration of < 4 ms. (author). 7 refs., 3 figs

Detection of silver nanoparticles in parsley by solid sampling high-resolution-continuum source atomic absorption spectrometry.

Science.gov (United States)

Feichtmeier, Nadine S; Leopold, Kerstin

2014-06-01

In this work, we present a fast and simple approach for detection of silver nanoparticles (AgNPs) in biological material (parsley) by solid sampling high-resolution-continuum source atomic absorption spectrometry (HR-CS AAS). A novel evaluation strategy was developed in order to distinguish AgNPs from ionic silver and for sizing of AgNPs. For this purpose, atomisation delay was introduced as significant indication of AgNPs, whereas atomisation rates allow distinction of 20-, 60-, and 80-nm AgNPs. Atomisation delays were found to be higher for samples containing silver ions than for samples containing silver nanoparticles. A maximum difference in atomisation delay normalised by the sample weight of 6.27 ± 0.96 s mg(-1) was obtained after optimisation of the furnace program of the AAS. For this purpose, a multivariate experimental design was used varying atomisation temperature, atomisation heating rate and pyrolysis temperature. Atomisation rates were calculated as the slope of the first inflection point of the absorbance signals and correlated with the size of the AgNPs in the biological sample. Hence, solid sampling HR-CS AAS was proved to be a promising tool for identifying and distinguishing silver nanoparticles from ionic silver directly in solid biological samples.

Parametric Investigation of Miniaturized Cylindrical and Annular Hall Thrusters

International Nuclear Information System (INIS)

Smirnov, A.; Raitses, Y.; Fisch, N.J.

2002-01-01

Conventional annular Hall thrusters become inefficient when scaled to low power. An alternative approach, a 2.6-cm miniaturized cylindrical Hall thruster with a cusp-type magnetic field distribution, was developed and studied. Its performance was compared to that of a conventional annular thruster of the same dimensions. The cylindrical thruster exhibits discharge characteristics similar to those of the annular thruster, but it has a much higher propellant ionization efficiency. Significantly, a large fraction of multi-charged xenon ions might be present in the outgoing ion flux generated by the cylindrical thruster. The operation of the cylindrical thruster is quieter than that of the annular thruster. The characteristic peak in the discharge current fluctuation spectrum at 50-60 kHz appears to be due to ionization instabilities. In the power range 50-300 W, the cylindrical and annular thrusters have comparable efficiencies (15-32%) and thrusts (2.5-12 mN). For the annular configuration, a voltage less than 200 V was not sufficient to sustain the discharge at low propellant flow rates. The cylindrical thruster can operate at voltages lower than 200 V, which suggests that a cylindrical thruster can be designed to operate at even smaller power

Robotic Hand with Flexible Fingers for Grasping Cylindrical Objects

OpenAIRE

柴田, 瑞穂

2015-01-01

In this manuscript, a robotic hand for grasping a cylindrical object is proposed. This robotic hand has flexible fingers that can hold a cylindrical object during moving. We introduce a grasping strategy for a cylindrical object in terms of state transition graph. In this strategy the robotic hand picks up the cylindrical object utilizing a suction device before the hand grasp the object. We also design the flexible fingers; then, we investigate the validity of this robotic hand via several e...

Dynamics of cylindrical domain walls in smectic C liquid crystals

International Nuclear Information System (INIS)

Stewart, I W; Wigham, E J

2009-01-01

An analysis of the dynamics of cylindrical domain walls in planar aligned samples of smectic C liquid crystals is presented. A circular magnetic field, induced by an electric current, drives a time-dependent reorientation of the corresponding radially dependent director field. Nonlinear approximations to the relevant nonlinear dynamic equation, derived from smectic continuum theory, are solved in a comoving coordinated frame: exact solutions are found for a π-wall and numerical solutions are calculated for π/2-walls. Each calculation begins with an assumed initial state for the director that is a prescribed cylindrical domain wall. Such an initial wall will proceed to expand or contract as its central core propagates radially inwards or outwards, depending on the boundary conditions for the director, the elastic constants, the magnitude of the field and the sign of the magnetic anisotropy of the liquid crystal

Cylindrical continuous martingales and stochastic integration in infinite dimensions

NARCIS (Netherlands)

Veraar, M.C.; Yaroslavtsev, I.S.

2016-01-01

In this paper we define a new type of quadratic variation for cylindrical continuous local martingales on an infinite dimensional spaces. It is shown that a large class of cylindrical continuous local martingales has such a quadratic variation. For this new class of cylindrical continuous local

Method for improved gas-solids separation

Science.gov (United States)

Kusik, C.L.; He, B.X.

1990-11-13

Methods are disclosed for the removal of particulate solids from a gas stream at high separation efficiency, including the removal of submicron size particles. The apparatus includes a cyclone separator type of device which contains an axially mounted perforated cylindrical hollow rotor. The rotor is rotated at high velocity in the same direction as the flow of an input particle-laden gas stream to thereby cause enhanced separation of particulate matter from the gas stream in the cylindrical annular space between the rotor and the sidewall of the cyclone vessel. Substantially particle-free gas passes through the perforated surface of the spinning rotor and into the hollow rotor, from where it is discharged out of the top of the apparatus. Separated particulates are removed from the bottom of the vessel. 4 figs.

Solid-state disk amplifiers for fusion-laser systems

Energy Technology Data Exchange (ETDEWEB)

Martin, W.E.; Trenholme, J.B.; Linford, G.J.; Yarema, S.M.; Hurley, C.A.

1981-09-01

We review the design, performance, and operation of large-aperture (10 to 46 cm) solid-state disk amplifiers for use in laser systems. We present design data, prototype tests, simulations, and projections for conventional cylindrical pump-geometry amplifiers and rectangular pump-geometry disk amplifiers. The design of amplifiers for the Nova laser system is discussed.

Behavior of a heavy cylinder in a horizontal cylindrical liquid-filled cavity at modulated rotation

International Nuclear Information System (INIS)

Kozlov, Nikolai V; Vlasova, Olga A

2016-01-01

The behavior of a heavy cylindrical solid in a horizontal cylindrical cavity is experimentally investigated. The cavity is filled with a viscous liquid and rotates. Two rotation regimes are considered. The first one is steady rotation. A number of body motion regimes are found depending on the cavity rotation speed. The second regime is a modulated rotation, in which the rotation speed is varying periodically. It can be presented as a sum of steady rotation and librations. On the whole, three different cases of the body repulsion from the cavity wall are observed. In the first case, the repulsion occurs when the body slides over a rotating cavity wall. In the second case, the body being in the centrifuged state—when it rotates with the fluid—detaches from the cavity wall under the action of gravity. In the third case, at librations, the wall performs oscillations and the body is repulsed from the wall due to the nonlinear viscous interaction with the fluid. (paper)

Water-equivalent solid sources prepared by means of two distinct methods

International Nuclear Information System (INIS)

Koskinas, Marina F.; Yamazaki, Ione M.; Potiens Junior, Ademar

2014-01-01

The Nuclear Metrology Laboratory at IPEN is involved in developing radioactive water-equivalent solid sources prepared from an aqueous solution of acrylamide using two distinct methods for polymerization. One of them is the polymerization by high dose of 60 Co irradiation; in the other method the solid matrix-polyacrylamide is obtained from an aqueous solution composed by acrylamide, catalyzers and an aliquot of a radionuclide. The sources have been prepared in cylindrical geometry. In this paper, the study of the distribution of radioactive material in the solid sources prepared by both methods is presented. (author)

Design and modeling of precision solid liner experiments on Pegasus

International Nuclear Information System (INIS)

Bowers, R.L.; Brownell, J.H.; Lee, H.; McLenithan, K.D.; Scannapieco, A.J.; Shanahan, W.R.

1998-01-01

Pulsed power driven solid liners may be used for a variety of physics experiments involving materials at high stresses. These include shock formation and propagation, material strain-rate effects, material melt, instability growth, and ejecta from shocked surfaces. We describe the design and performance of a cylindrical solid liner that can attain velocities in the several mm/μs regime, and that can be used to drive high-stress experiments. An approximate theoretical analysis of solid liner implosions is used to establish the basic parameters (mass, materials, and initial radius) of the driver. We then present one-dimensional and two-dimensional simulations of magnetically driven, liner implosions which include resistive heating and elastic endash plastic behavior. The two-dimensional models are used to study the effects of electrode glide planes on the liner close-quote s performance, to examine sources of perturbations of the liner, and to assess possible effects of instability growth during the implosion. Finally, simulations are compared with experimental data to show that the solid liner performed as predicted computationally. Experimental data indicate that the liner imploded from an initial radius of 2.4 cm to a target radius of 1.5 cm, and that it was concentric and cylindrical to better than the experimental resolution (60 μm) at the target. The results demonstrate that a precision solid liner can be produced for high-stress, pulsed power applications experiments. copyright 1998 American Institute of Physics

Comparative solubilisation of potassium carbonate, sodium bicarbonate and sodium carbonate in hot dimethylformamide: application of cylindrical particle surface-controlled dissolution theory.

Science.gov (United States)

Forryan, Claire L; Compton, Richard G; Klymenko, Oleksiy V; Brennan, Colin M; Taylor, Catherine L; Lennon, Martin

2006-02-07

A surface-controlled dissolution of cylindrical solid particles model is applied to potassium carbonate, sodium bicarbonate and sodium carbonate in dimethylformamide at elevated temperatures. Previously published data for the dissolution of potassium carbonate is interpreted assuming a cylindrical rather than a spherical shape of the particles, the former representing a closer approximation to the true shape of the particles as revealed by scanning electron microscopy. The dissolution kinetics of sodium carbonate and sodium bicarbonate in dimethylformamide at 100 degrees C were investigated via monitoring of the deprotonation of 2-cyanophenol with dissolved solid to form the 2-cyanophenolate anion that was detected with UV-visible spectroscopy. From fitting of experimental results to theory, the dissolution rate constant, k, for the dissolutions of potassium carbonate, sodium bicarbonate and sodium carbonate in dimethylformamide at 100 degrees C were found to have the values of (1.0 +/- 0.1) x 10(-7) mol cm(-2) s(-1), (5.5 +/- 0.3) x 10(-9) mol cm(-2) s(-1) and (9.7 +/- 0.8) x 10(-9) mol cm(-2) s(-1), respectively.

Gastric emptying of solids: When should we sample

International Nuclear Information System (INIS)

Sfakianakis, G.; Spoliansky, G.; Cassady, J.; Barkin, J.; Serafini, A.

1984-01-01

Gastric emptying of solids has been studied for 20 normal volunteers using Tc-99m-sulfur-colloid labeled chicken liver or eggs. Residual gastric activity measured in 15 min intervals for 2 1/2 hrs was used to calculate gastric emptying. The procedure was proposed and is used to examine patients for suspected abnormal emptying. This approach however ties up one gamma camera and one technologist for a period of 2 1/2 - 3 hrs. Furthermore to classify any value more the 1SD below the mean as abnormal includes 16% of normals as abnormally low (false positives). In order to find the pattern of abnormalities and the best time to study patients we analyzed the results of 54 studies performed in patients with a variety of clinical problems. Gastric emptying was measured in 30 min intervals for 2 1/2 hrs after a standard meal of 2 scrambled eggs labeled with 1 mCi of Tc-99m-sulfur-colloid, 2 slices of bread and 300 ml of juice. To choose the point important to observe the authors studied the distribution of values at each time-point to determine when there is the greatest variability from the reported normal. When there is delayed emptying the 2 1/2 hr observation is the best discriminator and when there is accelerated emptying the 60 min observation is the best discriminator. In the group of patients the 150 min observation had no correlation with the age of the patients. It is possible that sampling at a later time could be more discriminatory. The authors propose sampling at 0, 60, and 150 min time as the most informative and cost effective approach to study the solid gastric emptying. The 2SD rather than 1SD below and above the mean should be used as the level to separate normal from abnormal results

Gastric emptying of solids: When should we sample

Energy Technology Data Exchange (ETDEWEB)

Sfakianakis, G.; Spoliansky, G.; Cassady, J.; Barkin, J.; Serafini, A.

1984-01-01

Gastric emptying of solids has been studied for 20 normal volunteers using Tc-99m-sulfur-colloid labeled chicken liver or eggs. Residual gastric activity measured in 15 min intervals for 2 1/2 hrs was used to calculate gastric emptying. The procedure was proposed and is used to examine patients for suspected abnormal emptying. This approach however ties up one gamma camera and one technologist for a period of 2 1/2 - 3 hrs. Furthermore to classify any value more the 1SD below the mean as abnormal includes 16% of normals as abnormally low (false positives). In order to find the pattern of abnormalities and the best time to study patients we analyzed the results of 54 studies performed in patients with a variety of clinical problems. Gastric emptying was measured in 30 min intervals for 2 1/2 hrs after a standard meal of 2 scrambled eggs labeled with 1 mCi of Tc-99m-sulfur-colloid, 2 slices of bread and 300 ml of juice. To choose the point important to observe the authors studied the distribution of values at each time-point to determine when there is the greatest variability from the reported normal. When there is delayed emptying the 2 1/2 hr observation is the best discriminator and when there is accelerated emptying the 60 min observation is the best discriminator. In the group of patients the 150 min observation had no correlation with the age of the patients. It is possible that sampling at a later time could be more discriminatory. The authors propose sampling at 0, 60, and 150 min time as the most informative and cost effective approach to study the solid gastric emptying. The 2SD rather than 1SD below and above the mean should be used as the level to separate normal from abnormal results.

Measuring Sulfur Isotope Ratios from Solid Samples with the Sample Analysis at Mars Instrument and the Effects of Dead Time Corrections

Science.gov (United States)

Franz, H. B.; Mahaffy, P. R.; Kasprzak, W.; Lyness, E.; Raaen, E.

2011-01-01

The Sample Analysis at Mars (SAM) instrument suite comprises the largest science payload on the Mars Science Laboratory (MSL) "Curiosity" rover. SAM will perform chemical and isotopic analysis of volatile compounds from atmospheric and solid samples to address questions pertaining to habitability and geochemical processes on Mars. Sulfur is a key element of interest in this regard, as sulfur compounds have been detected on the Martian surface by both in situ and remote sensing techniques. Their chemical and isotopic composition can belp constrain environmental conditions and mechanisms at the time of formation. A previous study examined the capability of the SAM quadrupole mass spectrometer (QMS) to determine sulfur isotope ratios of SO2 gas from a statistical perspective. Here we discuss the development of a method for determining sulfur isotope ratios with the QMS by sampling SO2 generated from heating of solid sulfate samples in SAM's pyrolysis oven. This analysis, which was performed with the SAM breadboard system, also required development of a novel treatment of the QMS dead time to accommodate the characteristics of an aging detector.

Read/write performance of perpendicular double-layered cylindrical media

International Nuclear Information System (INIS)

Yamada, H.; Shimatsu, T.; Watanabe, I.; Tsuchiyama, R.; Aoi, H.; Muraoka, H.; Nakamura, Y.

2005-01-01

A cylindrical magnetic storage system using perpendicular double-layered media has been developed. CoCrTa/CoZrNb deposited on a rotating cylindrical substrate shows perpendicular anisotropy and magnetic properties, which have almost the same characteristics as conventional disk-media. The fundamental read/write characteristics of perpendicular double-layered cylindrical media were measured using a single-pole-type (SPT) writer with a sliding-contact-type slider and a merged giant magneto-resistive (GMR) reader with a one-pad-type slider designed for use with cylindrical media. Preliminary studies for improving the characteristics of the recording layer are also described

A pyrolysis/gas chromatographic method for the determination of hydrogen in solid samples

Science.gov (United States)

Carr, R. H.; Bustin, R.; Gibson, E. K.

1987-01-01

A method is described for the determination of hydrogen in solid samples. The sample is heated under vacuum after which the evolved gases are separated by gas chromatography with a helium ionization detector. The system is calibrated by injecting known amounts of hydrogen, as determined manometrically. The method, which is rapid and reliable, was checked for a variety of lunar soils; the limit of detection is about 10 ng of hydrogen.

Impact of wall potential on the fluid-wall interaction in a cylindrical capillary and a generalized Kelvin equation

International Nuclear Information System (INIS)

Jakubov, T.S.; Mainwaring, D.E.

2006-01-01

In the present work a generalized Kelvin equation for a fluid confined in thick-walled cylindrical capillary is developed. This has been accomplished by including the potential energy function for interaction between a solid wall of a capillary and a confined fluid into the Kelvin equation. Using the Lennard-Jones 12-6 potential, an explicit form of the potential energy functions as expressed by hypergeometrical functions have been derived-firstly, for the interaction between a solid wall and a test atom placed at an arbitrary point in a long open-end capillary, and thereafter for the body-body interaction between the solid wall and a confined Lennard-Jones fluid. Further, this generalized Kelvin equation has been applied to detailed description hysteresis phenomena in such capillaries. All numerical calculations have been carried out for the model argon-graphite system at 90 K

Solid phase microextraction headspace sampling of chemical warfare agent contaminated samples : method development for GC-MS analysis

Energy Technology Data Exchange (ETDEWEB)

Jackson Lepage, C.R.; Hancock, J.R. [Defence Research and Development Canada, Medicine Hat, AB (Canada); Wyatt, H.D.M. [Regina Univ., SK (Canada)

2004-07-01

Defence R and D Canada-Suffield (DRDC-Suffield) is responsible for analyzing samples that are suspected to contain chemical warfare agents, either collected by the Canadian Forces or by first-responders in the event of a terrorist attack in Canada. The analytical techniques used to identify the composition of the samples include gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy. GC-MS and LC-MS generally require solvent extraction and reconcentration, thereby increasing sample handling. The authors examined analytical techniques which reduce or eliminate sample manipulation. In particular, this paper presented a screening method based on solid phase microextraction (SPME) headspace sampling and GC-MS analysis for chemical warfare agents such as mustard, sarin, soman, and cyclohexyl methylphosphonofluoridate in contaminated soil samples. SPME is a method which uses small adsorbent polymer coated silica fibers that trap vaporous or liquid analytes for GC or LC analysis. Collection efficiency can be increased by adjusting sampling time and temperature. This method was tested on two real-world samples, one from excavated chemical munitions and the second from a caustic decontamination mixture. 7 refs., 2 tabs., 3 figs.

Determination of radiocaesium in agriculture-related water samples containing suspended solids using gelling method

International Nuclear Information System (INIS)

Matsunami, Hisaya; Shin, Moono; Takahashi, Yoshihiko; Shinano, Takuro; Kitajima, Shiori; Tsuchiya, Takashi

2015-01-01

After the TEPCO Fukushima Dai-ichi Nuclear Power Plant accident in 2011, the radiocaesium, which flowed into the paddy fields via irrigation water, have been widely investigated. When the concentration of radiocaesium in the water samples containing suspended solids were directly measured using a high purity germanium detector with a 2 L marinelli beaker, the radiocaesium concentration might be overestimated due to the sedimentation of the suspended solids during the measurement time. In fact, the values obtained by the direct method were higher than those obtained by the filtering method and/or the gelling method in most of the agriculture-related water samples. We concluded that the gelling method using sodium polyacrylate can be widely adapted for the analysis of the total radiocaesium in the agriculture-related water samples because of its many advantage such as simple preparation procedure, accurate analysis values, excellent long-term stability of geometry and low operating cost. (author)

Cylindrical solitons in shallow water of variable depth

International Nuclear Information System (INIS)

Carbonaro, P.; Floris, R.; Pantano, P.

1983-01-01

The propagation and the interaction of cylindrical solitons in shallow water of variable depth are studied. Starting from the cylindrically symmetric version of the equations describing long waves in a beach, a Korteweg-de Vries equation is derived. Since no exact analytical solution has been found to date for this equation, some remarkable cases in which the equation takes up a tractable form are analyzed. Finally the intercation between cylindrical imploding and expanding waves is considered and the phase shifts caused by the head-on collision are given

Unbalanced Cylindrical Magnetron for Accelerating Cavities Coating

CERN Document Server

Rosaz, Guillaume; Calatroni, Sergio; Sublet, Alban; Tobarelli, Mauro

2016-01-01

We report in this paper the design and qualification of a cylindrical unbalanced magnetron source. The dedicated magnetic assemblies were simulated using a finite element model. A hall-effect magnetic probe was then used to characterize those assemblies and compared to the theoretical magnet profiles. These show a good agreement between the expected and actual values. the qualification of the different magnetic assemblies was then performed by measuring the ion flux density reaching the surface of the sample to be coated using a commercial retarding field energy analyzer. The strongest unbalanced configuration shows an increase from 0.016A.cm^-2 to 0.074A.cm^-2 of the ion flux density reaching the sample surface compared to the standard balanced configuration for a pressure 5.10^-3 mbar and a plasma source power of 300W.

Polychlorinated biphenyls (PCB) analysis report for solid sample from 219S tank 104

International Nuclear Information System (INIS)

Ross, G.A.

1998-01-01

A sample of solids was obtained from tank 104 of 219S via a peristaltic pump equipped with a stainless steel tube and Norprenel tubing (Phthalate free). The sample obtained in a glass jar with Teflon 2 lid, was analyzed for PCBs as Aroclor mixtures. A soxhlet extraction procedure was used to extract the Aroclors from the sample. Analysis was performed using dual column confirmation gas chromatography/electron capture detection (GC/ECD). The extraction method closely follows SW-846 method 3540C and the analysis follows SW-846 method

Moments of inertia for solids of revolution and variational methods

International Nuclear Information System (INIS)

Diaz, Rodolfo A; Herrera, William J; Martinez, R

2006-01-01

We present some formulae for the moments of inertia of homogeneous solids of revolution in terms of the functions that generate the solids. The development of these expressions exploits the cylindrical symmetry of these objects and avoids the explicit use of multiple integration, providing an easy and pedagogical approach. The explicit use of the functions that generate the solid gives the possibility of writing the moment of inertia as a functional, which in turn allows us to utilize the calculus of variations to obtain new insight into some properties of this fundamental quantity. In particular, minimization of moments of inertia under certain restrictions is possible by using variational methods

Analysis on Coupled Vibration of a Radially Polarized Piezoelectric Cylindrical Transducer

Directory of Open Access Journals (Sweden)

Jie Xu

2017-12-01

Full Text Available Coupled vibration of a radially polarized piezoelectric cylindrical transducer is analyzed with the mechanical coupling coefficient method. The method has been utilized to analyze the metal cylindrical transducer and the axially polarized piezoelectric cylindrical transducer. In this method, the mechanical coupling coefficient is introduced and defined as the stress ratio in different directions. Coupled vibration of the cylindrical transducer is regarded as the interaction of the plane radial vibration of a ring and the longitudinal vibration of a tube. For the radially polarized piezoelectric cylindrical transducer, the radial and longitudinal electric admittances as functions of mechanical coupling coefficients and angular frequencies are derived, respectively. The resonance frequency equations are obtained. The dependence of resonance frequency and mechanical coupling coefficient on aspect ratio is studied. Vibrational distributions on the surfaces of the cylindrical transducer are presented with experimental measurement. On the support of experiments, this work is verified and provides a theoretical foundation for the analysis and design of the radially polarized piezoelectric cylindrical transducer.

Plastic buckling of cylindrical shells

International Nuclear Information System (INIS)

Bandyopadhyay, K.; Xu, J.; Shteyngart, S.; Eckert, H.

1994-01-01

Cylindrical shells exhibit buckling under axial loads at stresses much less than the respective theoretical critical stresses. This is due primarily to the presence of geometrical imperfections even though such imperfections could be very small (e.g., comparable to thickness). Under internal pressure, the shell regains some of its buckling strength. For a relatively large radius-to-thickness ratio and low internal pressure, the effect can be reasonably estimated by an elastic analysis. However, for low radius-to-thickness ratios and greater pressures, the elastic-plastic collapse controls the failure load. in order to quantify the elastic-plastic buckling capacity of cylindrical shells, an analysis program was carried out by use of the computer code BOSOR5 developed by Bushnell of Lockheed Missiles and Space Company. The analysis was performed for various radius-to-thickness ratios and imperfection amplitudes. The purpose of the analytical program was to compute the buckling strength of underground cylindrical tanks, that are used for storage of nuclear wastes, for realistic geometric imperfections and internal pressure loads. This paper presents the results of the elastic-plastic analyses and compares them with other available information for various pressure loads

Cylindrical Piezoelectric Fiber Composite Actuators

Science.gov (United States)

Allison, Sidney G.; Shams, Qamar A.; Fox, Robert L.

2008-01-01

The use of piezoelectric devices has become widespread since Pierre and Jacques Curie discovered the piezoelectric effect in 1880. Examples of current applications of piezoelectric devices include ultrasonic transducers, micro-positioning devices, buzzers, strain sensors, and clocks. The invention of such lightweight, relatively inexpensive piezoceramic-fiber-composite actuators as macro fiber composite (MFC) actuators has made it possible to obtain strains and displacements greater than those that could be generated by prior actuators based on monolithic piezoceramic sheet materials. MFC actuators are flat, flexible actuators designed for bonding to structures to apply or detect strains. Bonding multiple layers of MFC actuators together could increase force capability, but not strain or displacement capability. Cylindrical piezoelectric fiber composite (CPFC) actuators have been invented as alternatives to MFC actuators for applications in which greater forces and/or strains or displacements may be required. In essence, a CPFC actuator is an MFC or other piezoceramic fiber composite actuator fabricated in a cylindrical instead of its conventional flat shape. Cylindrical is used here in the general sense, encompassing shapes that can have circular, elliptical, rectangular or other cross-sectional shapes in the planes perpendicular to their longitudinal axes.

Ingestion of six cylindrical and four button batteries

DEFF Research Database (Denmark)

Nielsen, Simon U; Rasmussen, Morten; Hoegberg, Lotte C G

2010-01-01

We report a suicidal ingestion of six cylindrical and four button batteries, in combination with overdosed prescription medicine and smoking of cannabis.......We report a suicidal ingestion of six cylindrical and four button batteries, in combination with overdosed prescription medicine and smoking of cannabis....

Cylindric-like algebras and algebraic logic

CERN Document Server

Ferenczi, Miklós; Németi, István

2013-01-01

Algebraic logic is a subject in the interface between logic, algebra and geometry, it has strong connections with category theory and combinatorics. Tarski’s quest for finding structure in logic leads to cylindric-like algebras as studied in this book, they are among the main players in Tarskian algebraic logic. Cylindric algebra theory can be viewed in many ways:  as an algebraic form of definability theory, as a study of higher-dimensional relations, as an enrichment of Boolean Algebra theory, or, as logic in geometric form (“cylindric” in the name refers to geometric aspects). Cylindric-like algebras have a wide range of applications, in, e.g., natural language theory, data-base theory, stochastics, and even in relativity theory. The present volume, consisting of 18 survey papers, intends to give an overview of the main achievements and new research directions in the past 30 years, since the publication of the Henkin-Monk-Tarski monographs. It is dedicated to the memory of Leon Henkin.

Investigation of the suspected presence of solid hydrocarbon in bedded salt samples from the Palo Duro Basin, Texas

International Nuclear Information System (INIS)

1985-10-01

This report contains laboratory test results for two bedded salt samples from the Grabbe No. 1 (PD-2) Well of the Palo Duro Basin, Texas. This study was commissioned to determine whether or not solid hydrocarbons exist in bedded salt samples in the Palo Duro Basin. Laboratory investigations include electron microprobe examinations on polished thin sections and optical examinations and chemical tests on insoluble residues of the salt samples. No direct evidence was found that identifiable solid hydrocarbons are present in either sample of the bedded salt core. The total carbon content of the two salt samples was measured yielding 0.016 and 0.022 weight percent carbon. Detailed microscopic analyses showed that the carbon in the samples was associated with calcite, clays, and the epoxy resin used in sample preparation

Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

DEFF Research Database (Denmark)

Edjabou, Vincent Maklawe Essonanawe; Jensen, Morten Bang; Götze, Ramona

2015-01-01

Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both...... comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub......-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10-50 waste fractions, organised according to a three-level (tiered approach) facilitating,comparison of the waste data between individual sub-areas with different fractionation (waste...

Coupled dilaton and electromagnetic field in cylindrically symmetric ...

Indian Academy of Sciences (India)

The dilaton black hole solutions have attracted considerable attention for the ... theory and study the corresponding cylindrically symmetric spacetime, where .... where Йm and Йe are integration constants to be interpreted later as the ..... feature is apparent for the cylindrically symmetric spacetime in the presence of the dila-.

Tearing instability in cylindrical plasma configuration

International Nuclear Information System (INIS)

Zelenyj, L.M.

1979-01-01

The effect of the neutral-layer cylindrical geometry on the development of the tearing instability has been investigated in detail. The increments of the instability for all the regimes have been found. The influence of cylindrical effects becomes manifesting itself at small, as compared to the layer characteristic thickness, distances from the axis, and, finally, the electron regime of the instability development transforms into an ion one. The results obtained are of interest for studying the plasma stability in the devices of the ''Astron'' type and in magnetospheres of cosmic objects

Magnetic guns with cylindrical permanent magnets

DEFF Research Database (Denmark)

Vokoun, David; Beleggia, Marco; Heller, Luděk

2012-01-01

The motion of a cylindrical permanent magnet (projectile) inside a tubular permanent magnet, with both magnets magnetized axially, illustrates nicely the physical principles behind the operation of magnetic guns. The force acting upon the projectile is expressed semi-analytically as derivative...... of the magnetostatic interaction energy. For comparison, the forces involved are also calculated numerically using finite elements methods. Based on the conservation of the magnetostatic and kinetic energies, the exit and asymptotic velocities are determined. The derived formulas can be used to optimize the generated...... forces and motion of the inner cylindrical magnet....

Real-Time Laser Ultrasound Tomography for Profilometry of Solids

Science.gov (United States)

Zarubin, V. P.; Bychkov, A. S.; Karabutov, A. A.; Simonova, V. A.; Kudinov, I. A.; Cherepetskaya, E. B.

2018-01-01

We studied the possibility of applying laser ultrasound tomography for profilometry of solids. The proposed approach provides high spatial resolution and efficiency, as well as profilometry of contaminated objects or objects submerged in liquids. The algorithms for the construction of tomograms and recognition of the profiles of studied objects using the parallel programming technology NDIVIA CUDA are proposed. A prototype of the real-time laser ultrasound profilometer was used to obtain the profiles of solid surfaces of revolution. The proposed method allows the real-time determination of the surface position for cylindrical objects with an approximation accuracy of up to 16 μm.

Cylindrical dust acoustic waves with transverse perturbation

International Nuclear Information System (INIS)

Xue Jukui

2003-01-01

The nonlinear dust acoustic waves in dusty plasmas with the combined effects of bounded cylindrical geometry and the transverse perturbation are studied. Using the perturbation method, a cylindrical Kadomtsev-Petviashvili (CKP) equation that describes the dust acoustic waves is deduced for the first time. A particular solution of this CKP equation is also obtained. It is shown that the dust acoustic solitary waves can exist in the CKP equation

Localisation and identification of radioactive particles in solid samples by means of a nuclear track technique

International Nuclear Information System (INIS)

Boehnke, Antje; Treutler, Hanns-Christian; Freyer, Klaus; Schubert, Michael; Holger Weiss

2005-01-01

This study is aimed to develop a generally applicable methodology of investigation that can be used for the localisation of single alpha-active particles in solid samples, such as industrial dust or natural soils, sediments and rocks by autoradiography using solid-state nuclear track detectors. The developed technique allows the detection of local enrichments of alpha-emitters in any solid material. The results of such an investigation are of interest from technical, biological and environmental points of view. The idea behind the methodology is to locate the position of alpha-active spots in a sample by attaching the track detector to the sample in a defined manner, thoroughly described in the paper. The located alpha-active particles are subsequently analysed by an electron microscope and an electron microprobe. An example of the application of this methodology is also given. An ultra-fine -grained ore-processing residue, which causes serious environmental pollution in the respective mining district and thus limits possible land use and affects quality of life in the area, was examined using the described technique. The investigation revealed considerable amounts of alpha-active particles in this material

Efficient sample preparation method based on solvent-assisted dispersive solid-phase extraction for the trace detection of butachlor in urine and waste water samples.

Science.gov (United States)

Aladaghlo, Zolfaghar; Fakhari, Alireza; Behbahani, Mohammad

2016-10-01

In this work, an efficient sample preparation method termed solvent-assisted dispersive solid-phase extraction was applied. The used sample preparation method was based on the dispersion of the sorbent (benzophenone) into the aqueous sample to maximize the interaction surface. In this approach, the dispersion of the sorbent at a very low milligram level was achieved by inserting a solution of the sorbent and disperser solvent into the aqueous sample. The cloudy solution created from the dispersion of the sorbent in the bulk aqueous sample. After pre-concentration of the butachlor, the cloudy solution was centrifuged and butachlor in the sediment phase dissolved in ethanol and determined by gas chromatography with flame ionization detection. Under the optimized conditions (solution pH = 7.0, sorbent: benzophenone, 2%, disperser solvent: ethanol, 500 μL, centrifuged at 4000 rpm for 3 min), the method detection limit for butachlor was 2, 3 and 3 μg/L for distilled water, waste water, and urine sample, respectively. Furthermore, the preconcentration factor was 198.8, 175.0, and 174.2 in distilled water, waste water, and urine sample, respectively. Solvent-assisted dispersive solid-phase extraction was successfully used for the trace monitoring of butachlor in urine and waste water samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Device for storage of cylindrical objects with quick loading-unloading system

International Nuclear Information System (INIS)

Besnier, J.

1995-01-01

This device comprises one or more co-axial rotative racks with radially distributed alveoles for the storage of cylindrical objects such as small jugs filled with radioactive samples. An opening is managed in each alveole for the ejection of the object towards a receptacle and alveoles are inclined with respect to the rotation axis of the rack to avoid casual fall of the objects. Selective ejection of the samples is obtained with ab toggle lever fitted inside each alveole and controlled by a single pneumatic jack. Details of manufacturing and description of parts are given. (J.S.). 6 refs., 2 figs

Fluid sampling tool

Science.gov (United States)

Garcia, Anthony R.; Johnston, Roger G.; Martinez, Ronald K.

1999-05-25

A fluid sampling tool for sampling fluid from a container. The tool has a fluid collecting portion which is drilled into the container wall, thereby affixing it to the wall. The tool may have a fluid extracting section which withdraws fluid collected by the fluid collecting section. The fluid collecting section has a fluted shank with an end configured to drill a hole into a container wall. The shank has a threaded portion for tapping the borehole. The shank is threadably engaged to a cylindrical housing having an inner axial passageway sealed at one end by a septum. A flexible member having a cylindrical portion and a bulbous portion is provided. The housing can be slid into an inner axial passageway in the cylindrical portion and sealed to the flexible member. The bulbous portion has an outer lip defining an opening. The housing is clamped into the chuck of a drill, the lip of the bulbous section is pressed against a container wall until the shank touches the wall, and the user operates the drill. Wall shavings (kerf) are confined in a chamber formed in the bulbous section as it folds when the shank advances inside the container. After sufficient advancement of the shank, an o-ring makes a seal with the container wall.

Wave motion in elastic solids

CERN Document Server

Graff, Karl F

1991-01-01

This highly useful textbook presents comprehensive intermediate-level coverage of nearly all major topics of elastic wave propagation in solids. The subjects range from the elementary theory of waves and vibrations in strings to the three-dimensional theory of waves in thick plates. The book is designed not only for a wide audience of engineering students, but also as a general reference for workers in vibrations and acoustics. Chapters 1-4 cover wave motion in the simple structural shapes, namely strings, longitudinal rod motion, beams and membranes, plates and (cylindrical) shells. Chapter

Evaluation of solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry for direct determination of chromium in medicinal plants

International Nuclear Information System (INIS)

Virgilio, Alex; Nóbrega, Joaquim A.; Rêgo, Jardes F.; Neto, José A. Gomes

2012-01-01

A method for Cr determination in medicinal plants using direct solid sampling graphite furnace high-resolution continuum source atomic absorption spectrometry was developed. Modifiers were dispensable. Pyrolysis and atomization temperatures were 1500 °C and 2400 °C, respectively. Slopes of calibration curves (50–750 pg Cr, R 2 > 0.999) using aqueous and solid standards coincides in 96%, indicated feasibility of aqueous calibration for solid sampling of medicinal plants. Accuracy was checked by analysis of four plant certified reference materials. Results were in agreement at 95% confidence level with certified and non-certified values. Ten samples of medicinal plants were analyzed and Cr contents were in the 1.3–17.7 μg g −1 Cr range. The highest RSD (n = 5) was 15.4% for the sample Melissa officinalis containing 13.9 ± 2.1 μg g −1 Cr. The limit of detection was 3.3 ng g −1 Cr. - Highlights: ► Direct solid sampling is first time employed for Cr in plant materials. ► Calibration curves with liquids and solids are coincident. ► Microanalysis of plants for Cr is validated by reference materials. ► The proposed HR-CS GF AAS method is environmental friendly.

Evaluation of solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry for direct determination of chromium in medicinal plants

Energy Technology Data Exchange (ETDEWEB)

Virgilio, Alex; Nobrega, Joaquim A. [Department of Chemistry, Federal University of Sao Carlos, Post Office Box 676, 13560-970, Sao Carlos-SP (Brazil); Rego, Jardes F. [Department of Analytical Chemistry, Institute of Chemistry, Sao Paulo State University-UNESP, Post Office Box 355, 14801-970, Araraquara-SP (Brazil); Neto, Jose A. Gomes, E-mail: anchieta@iq.unesp.br [Department of Analytical Chemistry, Institute of Chemistry, Sao Paulo State University-UNESP, Post Office Box 355, 14801-970, Araraquara-SP (Brazil)

2012-12-01

A method for Cr determination in medicinal plants using direct solid sampling graphite furnace high-resolution continuum source atomic absorption spectrometry was developed. Modifiers were dispensable. Pyrolysis and atomization temperatures were 1500 Degree-Sign C and 2400 Degree-Sign C, respectively. Slopes of calibration curves (50-750 pg Cr, R{sup 2} > 0.999) using aqueous and solid standards coincides in 96%, indicated feasibility of aqueous calibration for solid sampling of medicinal plants. Accuracy was checked by analysis of four plant certified reference materials. Results were in agreement at 95% confidence level with certified and non-certified values. Ten samples of medicinal plants were analyzed and Cr contents were in the 1.3-17.7 {mu}g g{sup -1} Cr range. The highest RSD (n = 5) was 15.4% for the sample Melissa officinalis containing 13.9 {+-} 2.1 {mu}g g{sup -1} Cr. The limit of detection was 3.3 ng g{sup -1} Cr. - Highlights: Black-Right-Pointing-Pointer Direct solid sampling is first time employed for Cr in plant materials. Black-Right-Pointing-Pointer Calibration curves with liquids and solids are coincident. Black-Right-Pointing-Pointer Microanalysis of plants for Cr is validated by reference materials. Black-Right-Pointing-Pointer The proposed HR-CS GF AAS method is environmental friendly.

Radon progeny distribution in cylindrical diffusion chambers

International Nuclear Information System (INIS)

Pressyanov, Dobromir S.

2008-01-01

An algorithm to model the diffusion of radioactive decay chain atoms is presented. Exact mathematical solutions in cylindrical geometry are given. They are used to obtain expressions for the concentrations of 222 Rn progeny atoms in the volume and deposited on the wall surface in cylindrical diffusion chambers. The dependence of volume fractions of 222 Rn progeny and chamber sensitivity on the coefficient of diffusion of 222 Rn progeny atoms in air is modeled.

Cylindrical geometry for proportional and drift chambers

International Nuclear Information System (INIS)

Sadoulet, B.

1975-06-01

For experiments performed around storage rings such as e + e - rings or the ISR pp rings, cylindrical wire chambers are very attractive. They surround the beam pipe completely without any dead region in the azimuth, and fit well with the geometry of events where particles are more or less spherically produced. Unfortunately, cylindrical proportional or drift chambers are difficult to make. Problems are discussed and two approaches to fabricating the cathodes are discussed. (WHK)

Development of new cylindrical magnetrons for industrial use

International Nuclear Information System (INIS)

Clayton, B.

2000-09-01

A number of alternative techniques were considered and tested with a view to the construction of a cylindrical sputtering device. This device was required to be capable of depositing tribological coatings inside approximately cylindrical substrates of diameters less than 100mm, in an industrial situation. A cylindrical magnetron device was designed, and constructed as a prototype, using a magnetic assembly inside a cylindrical target with outside diameter (o.d.) 40mm. Two alternative magnetic assemblies were tested, and found to have complimentary advantages. The magnetron characteristics of the device were tested, as were key properties (such as adhesion level and hardness) of the coatings deposited. In all cases good results were obtained. A 22mm o.d. device based on the same design was shown to operate, but with less satisfactory characteristics. In an attempt to improve the miniaturised design, the feasibility of gas cooling (rather than water cooling) the cylindrical magnetron was demonstrated. A system incorporating four 40mm o.d. cylindrical magnetrons was designed, constructed and briefly tested. This was intended to prove the feasibility of using a multi-magnetron system to reduce the cost to coat. Its dimensions and design were tailored to an industrially specified engine block. In use the plasma rings formed on the 40mm magnetron target surfaces during operation were found to be of unequal intensities, especially on the shorter magnetron design used in the four-fold system. In an attempt to tackle this problem, a finite element model of the magnetic field generated by the magnetic assembly was built, run and verified. Changes were made to this model, and a new .magnet assembly was built and tested based on the results obtained. This did not lead to a final solution of the problem, but has set bounds within which the solution must lie. (author)

Developments of solid materials for UF₆ sampling

Energy Technology Data Exchange (ETDEWEB)

Smith, Nicholas [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hebden, Andrew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Savina, Joseph [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

2017-11-15

This project demonstrated that a device using majority Commercial Off the Shelf (COTS) components could be used to collect uranium hexafluoride samples safely from gaseous or solid sources. The device was based on the successful Cristallini method developed by ABACC over the past 10 years. The system was designed to capture and store the UF₆ as an inert fluoride salt to ease transportation regulations. In addition, the method was considerably faster than traditional cryogenic methods, collected enough material to perform analyses without undue waste, and could be used either inside a facility or in the storage yard.

Permeability and compression characteristics of municipal solid waste samples

Science.gov (United States)

Durmusoglu, Ertan; Sanchez, Itza M.; Corapcioglu, M. Yavuz

2006-08-01

Four series of laboratory tests were conducted to evaluate the permeability and compression characteristics of municipal solid waste (MSW) samples. While the two series of tests were conducted using a conventional small-scale consolidometer, the two others were conducted in a large-scale consolidometer specially constructed for this study. In each consolidometer, the MSW samples were tested at two different moisture contents, i.e., original moisture content and field capacity. A scale effect between the two consolidometers with different sizes was investigated. The tests were carried out on samples reconsolidated to pressures of 123, 246, and 369 kPa. Time settlement data gathered from each load increment were employed to plot strain versus log-time graphs. The data acquired from the compression tests were used to back calculate primary and secondary compression indices. The consolidometers were later adapted for permeability experiments. The values of indices and the coefficient of compressibility for the MSW samples tested were within a relatively narrow range despite the size of the consolidometer and the different moisture contents of the specimens tested. The values of the coefficient of permeability were within a band of two orders of magnitude (10-6-10-4 m/s). The data presented in this paper agreed very well with the data reported by previous researchers. It was concluded that the scale effect in the compression behavior was significant. However, there was usually no linear relationship between the results obtained in the tests.

Analysis of the compressive behaviour of the three-dimensional printed porous titanium for dental implants using a modified cellular solid model.

Science.gov (United States)

Gagg, Graham; Ghassemieh, Elaheh; Wiria, Florencia E

2013-09-01

A set of cylindrical porous titanium test samples were produced using the three-dimensional printing and sintering method with samples sintered at 900 °C, 1000 °C, 1100 °C, 1200 °C or 1300 °C. Following compression testing, it was apparent that the stress-strain curves were similar in shape to the curves that represent cellular solids. This is despite a relative density twice as high as what is considered the threshold for defining a cellular solid. As final sintering temperature increased, the compressive behaviour developed from being elastic-brittle to elastic-plastic and while Young's modulus remained fairly constant in the region of 1.5 GPa, there was a corresponding increase in 0.2% proof stress of approximately 40-80 MPa. The cellular solid model consists of two equations that predict Young's modulus and yield or proof stress. By fitting to experimental data and consideration of porous morphology, appropriate changes to the geometry constants allow modification of the current models to predict with better accuracy the behaviour of porous materials with higher relative densities (lower porosity).

[Chemical constituents from endophyte Chaetomium globosum in Imperata cylindrical].

Science.gov (United States)

Shen, Li; Zhu, Li; Wei, Zhong-qi; Li, Xiao-wen; Li, Ming; Song, Yong-chun

2015-12-01

Isolation and purification of chemical constituents from solid culture of endophyte Chaetomium globosum in Imperata cylindrical was performed through silica gel column chromatography, gel filtration over Sephadex LH-20 and preparative HPLC. Nine compounds were obtained and their structures were determined as chaetoglobosin F(1), chaetoglobosin Fex(2), chaetoglobosin E(3) cytoglobosin A(4), penochalasin C(S), isochaetoglobosin D (6), N-benzoylphenylalaninyl-N-benzoyphenylalaninate(7), uracil(8) and 5-methyluracil(9), respectively, based on HR-MS and NMR data and comparison with literatures. Compound 7 was isolated from Chaeeomium sp. for the first time. In vitro cytotoxicity of compounds was evaluated using MTT mothed and 1,3,4 and 5 showed inhibition activity to the human cervical carcinoma cell HeLa with IC50 values of 99.43, 23.77, 97.92, 86.25 micromol x L(-1), while positive cotolocisnin Ad apno1ch alse IC50 24.33 micromol x L(-1).

Sample preparation with solid phase microextraction and exhaustive extraction approaches: Comparison for challenging cases.

Science.gov (United States)

Boyacı, Ezel; Rodríguez-Lafuente, Ángel; Gorynski, Krzysztof; Mirnaghi, Fatemeh; Souza-Silva, Érica A; Hein, Dietmar; Pawliszyn, Janusz

2015-05-11

In chemical analysis, sample preparation is frequently considered the bottleneck of the entire analytical method. The success of the final method strongly depends on understanding the entire process of analysis of a particular type of analyte in a sample, namely: the physicochemical properties of the analytes (solubility, volatility, polarity etc.), the environmental conditions, and the matrix components of the sample. Various sample preparation strategies have been developed based on exhaustive or non-exhaustive extraction of analytes from matrices. Undoubtedly, amongst all sample preparation approaches, liquid extraction, including liquid-liquid (LLE) and solid phase extraction (SPE), are the most well-known, widely used, and commonly accepted methods by many international organizations and accredited laboratories. Both methods are well documented and there are many well defined procedures, which make them, at first sight, the methods of choice. However, many challenging tasks, such as complex matrix applications, on-site and in vivo applications, and determination of matrix-bound and free concentrations of analytes, are not easily attainable with these classical approaches for sample preparation. In the last two decades, the introduction of solid phase microextraction (SPME) has brought significant progress in the sample preparation area by facilitating on-site and in vivo applications, time weighted average (TWA) and instantaneous concentration determinations. Recently introduced matrix compatible coatings for SPME facilitate direct extraction from complex matrices and fill the gap in direct sampling from challenging matrices. Following introduction of SPME, numerous other microextraction approaches evolved to address limitations of the above mentioned techniques. There is not a single method that can be considered as a universal solution for sample preparation. This review aims to show the main advantages and limitations of the above mentioned sample

Propagation of a cylindrical shock wave in a rotating dusty gas with heat conduction and radiation heat flux

International Nuclear Information System (INIS)

Vishwakarma, J P; Nath, G

2010-01-01

A self-similar solution for the propagation of a cylindrical shock wave in a dusty gas with heat conduction and radiation heat flux, which is rotating about the axis of symmetry, is investigated. The shock is assumed to be driven out by a piston (an inner expanding surface) and the dusty gas is assumed to be a mixture of non-ideal gas and small solid particles. The density of the ambient medium is assumed to be constant. The heat conduction is expressed in terms of Fourier's law and radiation is considered to be of diffusion type for an optically thick grey gas model. The thermal conductivity K and the absorption coefficient α R are assumed to vary with temperature and density. Similarity solutions are obtained, and the effects of variation of the parameter of non-idealness of the gas in the mixture, the mass concentration of solid particles and the ratio of density of solid particles to the initial density of the gas are investigated.

Micromagnetic simulations of cylindrical magnetic nanowires

KAUST Repository

Ivanov, Yurii P.

2015-05-27

This chapter reviews micromagnetic simulations of cylindrical magnetic nanowires and their ordered arrays. It starts with a description of the theoretical background of micromagnetism. The chapter discusses main magnetization reversal modes, domain wall types, and state diagrams in cylindrical nanowires of different types and sizes. The results of the hysteresis process in individual nanowires and nanowire arrays also are presented. Modeling results are compared with experimental ones. The chapter also discusses future trends in nanowire applications in relation to simulations, such as current-driven dynamics, spintronics, and spincaloritronics. The main micromagnetic programs are presented and discussed, together with the corresponding links.

The study of flow and proton exchange interactions in the cylindrical solid oxide fuel cell

CERN Document Server

Saievar-Iranizad, E

2002-01-01

The solid oxide fuel cell operates at high temperature of about 1000 deg C. In this temperature, some known materials such as Ni, ... which is abundant in the nature, can be used as a catalyst in the electrodes. The electrolytes of such cell solid oxide fuel cell can be made through non-porous solid ceramics such as Zircon's (ZrO sub 2). It can be stabilized using a doped Yttrium oxide. The importance of Yttria-stabilised Zirconia at high temperature belongs to the transport of oxygen ions through the electrolyte. Oxygen using in the hot cathode side causes a considerable reduction in the concentration of oxygen molecules. The oxygen ions exchange through the electrolyte relates to the molecular oxygen concentration gradient between the anode and cathode. Applying fuels such as hydrogen or natural gas in the anode and its chemical reaction with oxygen ions transfer from cathode through the electrolyte, produce electricity, water and heat. To study the ion exchange and its interaction into solid oxide fuel cel...

Polychlorinated biphenyls (PCB) analysis report for solid sample from 219S tank 101

International Nuclear Information System (INIS)

Diaz, L.A.

1998-01-01

One waste sample that was obtained with solids from tank 101 of 219S via a peristaltic pump equipped with a stainless steel tube and Norprene tubing (Phthalate free) was obtained in a glass jar with teflon lid was analyzed (with duplicate, matrix spike, and matrix spike duplicate) for PCBs as Aroclor mixtures by the Inorganic/Organic Chemistry Group. A soxhlet extraction procedure was used for extraction of the Aroclors from the sample. Analysis was performed using dual column confirmation gas chromatography/electron capture detection (GC/ECD). Results are presented

Low-energy impact of adaptive cylindrical piezoelectric-composite shells

Energy Technology Data Exchange (ETDEWEB)

Saravanos, D.A. [University of Patras (United Kingdom). Dept. of Mechanical Engineering and Aeronautics; Christoforou, A.P. [Kuwait Univ. (Kuwait). Dept. of Mechanical Engineering

2002-04-01

A theoretical framework for analyzing low-energy impacts of laminated shells with active and sensory piezoelectric layers is presented, including impactor dynamics and contact law. The formulation encompasses a coupled piezoelectric shell theory mixing first order shear displacement assumptions and layerwise variation of electric potential. An exact in-plane Ritz solution for the impact of open cylindrical piezoelectric-composite shells is developed and solved numerically using an explicit time integration scheme. The active impact control problem of adaptive cylindrical shells with distributed curved piezoelectric actuators is addressed. The cases of optimized state feedback controllers and output feedback controllers using piezoelectric sensors are analyzed. Numerical results quantify the impact response of cylindrical shells of various curvatures including the signal of curved piezoelectric sensors. Additional numerical studies quantify the impact response of adaptive cylindrical panels and investigate the feasibility of actively reducing the impact force. (author)

Note: Electrochemical etching of cylindrical nanoprobes using a vibrating electrolyte

International Nuclear Information System (INIS)

Wang, Yufeng; Zeng, Yongbin; Qu, Ningsong; Zhu, Di

2015-01-01

An electrochemical etching process using a vibrating electrolyte of potassium hydroxide to prepare tungsten cylindrical nanotips is developed. The vibrating electrolyte eases the effects of a diffusion layer and extends the etching area, which aid in the production of cylindrical nanotips. Larger amplitudes and a vibration frequency of 35 Hz are recommended for producing cylindrical nanotips. Nanotips with a tip radius of approximately 43 nm and a conical angle of arctan 0.0216 are obtained

Far-field potentials in cylindrical and rectangular volume conductors.

Science.gov (United States)

Dumitru, D; King, J C; Rogers, W E

1993-07-01

The occurrence of a transient dipole is one method of producing a far-field potential. This investigation qualitatively defines the characteristics of the near-field and far-field electrical potentials produced by a transient dipole in both cylindrical and rectangular volume conductors. Most body segments of electrophysiologic interest such as arms, legs, thorax, and neck are roughly cylindrical in shape. A centrally located dipole generator produces a nonzero equipotential region which is found to occur along the cylindrical wall at a distance from the dipole of approximately 1.4 times the cylinder's radius and 1.9 times the cylinder's radius for the center of the cylinder. This distance to the equi-potential zone along the surface wall expands but remains less than 3.0 times the cylindrical radius when the dipole is eccentrically placed. The magnitude of the equipotential region resulting from an asymmetrically placed dipole remains identical to that when the dipole is centrally located. This behavior is found to be very similar in rectangular shallow conducting volumes that model a longitudinal slice of the cylinder, thus allowing a simple experimental model of the cylinder to be utilized. Amplitudes of the equipotential region are inversely proportional to the cylindrical or rectangular volume's cross-sectional area at the location of dipolar imbalance. This study predicts that referential electrode montages, when placed at 3.0 times the radius or greater from a dipolar axially aligned far-field generator in cylindrical homogeneous volume conductors, will record only equipotential far-field effects.

Effects of sample preparation conditions on biomolecular solid-state NMR lineshapes

Energy Technology Data Exchange (ETDEWEB)

Jakeman, David L.; Mitchell, Dan J.; Shuttleworth, Wendy A.; Evans, Jeremy N.S. [Washington State University, Department of Biochemistry and Biophysics (United States)

1998-10-15

Sample preparation conditions with the 46 kDa enzyme complex of 5-enolpyruvyl-shikimate-3-phosphate (EPSP) synthase, shikimate-3-phosphate (S3P) and glyphosate (GLP) have been examined in an attempt to reduce linewidths in solid-state NMR spectra. The linewidths of {sup 13}P resonances associated with enzyme bound S3P and GLP in the lyophilized ternary complex have been reduced to 150 {+-} 12 Hz and 125 {+-} 7 Hz respectively, by a variety of methods involving additives and freezing techniques.

A general assignment method for oriented sample (OS) solid-state NMR of proteins based on the correlation of resonances through heteronuclear dipolar couplings in samples aligned parallel and perpendicular to the magnetic field.

Science.gov (United States)

Lu, George J; Son, Woo Sung; Opella, Stanley J

2011-04-01

A general method for assigning oriented sample (OS) solid-state NMR spectra of proteins is demonstrated. In principle, this method requires only a single sample of a uniformly ¹⁵N-labeled membrane protein in magnetically aligned bilayers, and a previously assigned isotropic chemical shift spectrum obtained either from solution NMR on micelle or isotropic bicelle samples or from magic angle spinning (MAS) solid-state NMR on unoriented proteoliposomes. The sequential isotropic resonance assignments are transferred to the OS solid-state NMR spectra of aligned samples by correlating signals from the same residue observed in protein-containing bilayers aligned with their normals parallel and perpendicular to the magnetic field. The underlying principle is that the resonances from the same residue have heteronuclear dipolar couplings that differ by exactly a factor of two between parallel and perpendicular alignments. The method is demonstrated on the membrane-bound form of Pf1 coat protein in phospholipid bilayers, whose assignments have been previously made using an earlier generation of methods that relied on the preparation of many selectively labeled (by residue type) samples. The new method provides the correct resonance assignments using only a single uniformly ¹⁵N-labeled sample, two solid-state NMR spectra, and a previously assigned isotropic spectrum. Significantly, this approach is equally applicable to residues in alpha helices, beta sheets, loops, and any other elements of tertiary structure. Moreover, the strategy bridges between OS solid-state NMR of aligned samples and solution NMR or MAS solid-state NMR of unoriented samples. In combination with the development of complementary experimental methods, it provides a step towards unifying these apparently different NMR approaches. Copyright © 2011 Elsevier Inc. All rights reserved.

Sensitivity optimization in whispering gallery mode optical cylindrical biosensors

Science.gov (United States)

Khozeymeh, F.; Razaghi, M.

2018-01-01

Whispering-gallery-mode resonances propagated in cylindrical resonators have two angular and radial orders of l and i. In this work, the higher radial order whispering-gallery-mode resonances, (i = 1 - 4), at a fixed l are examined. The sensitivity of theses resonances is analysed as a function of the structural parameters of the cylindrical resonator like different radii and refractive index of composed material of the resonator. A practical application where cylindrical resonators are used for the measurement of glucose concentration in water is presented as a biosensor demonstrator. We calculate the wavelength shifts of the WG1-4, in several glucose/water solutions, with concentrations spanning from 0.0% to 9.0.% (weight/weight). Improved sensitivity can be achieved using multi-WGM cylindrical resonators with radius of R = 100 μm and resonator composed material of MgF 2 with refractive index of nc = 1.38. Also the effect of polarization on sensitivity is considered for all four WGMs. The best sensitivity of 83.07 nm/RIU for the fourth WGM with transverse magnetic polarization, is reported. These results propose optimized parameters aimed to fast designing of cylindrical resonators as optical biosensors, where both the sensitivity and the geometries can be optimized.

Determination of self-absorption coefficient in measurement of solid sample activity using 4π ionization chamber

International Nuclear Information System (INIS)

Dryak, P.

1982-01-01

Computation based on the Monte Carlo method was tested for a 4π cylindrical ionization chamber with a detection volume of 7 litres, filled with argon. The sources are placed in the geometrical centre. The correction coefficient for self-absorption was determined as being the ratio of ionization currents induced by a source of finite size and by a massless point source. A flowchart of the program is given. The computations were experimentally tested for cylindrical sources of aqueous 137 Cs and 57 Co solutions. (M.D.)

Molecularly imprinted solid-phase extraction of glutathione from urine samples

International Nuclear Information System (INIS)

Song, Renyuan; Hu, Xiaoling; Guan, Ping; Li, Ji; Zhao, Na; Wang, Qiaoli

2014-01-01

Molecularly imprinted polymer (MIP) particles for glutathione were synthesized through iniferter-controlled living radical precipitation polymerization (IRPP) under ultraviolet radiation at ambient temperature. Static adsorption, solid-phase extraction, and high-performance liquid chromatography were carried out to evaluate the adsorption properties and selective recognition characteristics of the polymers for glutathione and its structural analogs. The obtained IRPP-MIP particles exhibited a regularly spherical shape, rapid binding kinetics, high imprinting factor, and high selectivity compared with the MIP particles prepared using traditional free-radical precipitation polymerization. The selective separation and enrichment of glutathione from the mixture of glycyl-glycine and glutathione disulfide could be achieved on the IRPP-MIP cartridge. The recoveries of glutathione, glycyl-glycine, and glutathione disulfide were 95.6% ± 3.65%, 29.5% ± 1.26%, and 49.9% ± 1.71%, respectively. The detection limit (S/N = 3) of glutathione was 0.5 mg·L −1 . The relative standard deviations (RSDs) for 10 replicate detections of 50 mg·L −1 of glutathione were 5.76%, and the linear range of the calibration curve was 0.5 mg·L −1 to 200 mg·L −1 under optimized conditions. The proposed approach was successfully applied to determine glutathione in spiked human urine samples with recoveries of 90.24% to 96.20% and RSDs of 0.48% to 5.67%. - Highlights: • Imprinted polymer particles were prepared by IRPP at ambient temperature. • High imprinting factor, high selectivity, and rapid binding kinetics were achieved. • Selective solid-phase extraction of glutathione from human urine samples

Cylindrical and spherical dust-acoustic wave modulations in dusty ...

Indian Academy of Sciences (India)

Abstract. The nonlinear wave modulation of planar and non-planar (cylindrical and spherical) dust-acoustic waves (DAW) propagating in dusty plasmas, in the presence of non-extensive distribu- tions for ions and electrons is investigated. By employing multiple scales technique, a cylindrically and spherically modified ...

Settling of a cylindrical particle in a stagnant fluid

DEFF Research Database (Denmark)

Sørensen, Henrik; Rosendahl, Lasse; Yin, Chungen

The objective of this work is to collect data and develop models for cylindrical particles which could be used in numerical multiphase flow modeling. Trajectories of cylindrical particles settling in stagnant water are filmed from two directions in order to derive detailed information on their mo...

Power deposition in a cylindrical geometry using B-10 coatings

International Nuclear Information System (INIS)

Chung, A.K.; Prelas, M.A.

1983-01-01

The transport of charged particles produced by 10 B (n, α) Li and 235 U (n, νn) ff nuclear reactions in a two region cylindrical geometry is predicted. We employed a mean-range straight-flight approximation to calculate the power deposition by the charged particles in a gaseous medium. Our model demonstrated some features in a cylindrical experiment which were suspected but not proven. In the common slab model used by Guyot et al 1 and Romero 2 , the spatial distribution of power deposition is much flatter than it would be in a cylindrical model. A steeper gradient in the power deposition is expected in a cylindrical geometry than in a slab geometry. We also found that for a standard thickness of Boron-10 coating (1.73 μm) used in NPLs, the expected efficiency of a cylindrical geometry (7.5%) is much lower than the 12% efficiency predicted by the slab model. Indeed the use of slab geometry in modeling current NPL experimental devices is not accurate

SESAR: Addressing the need for unique sample identification in the Solid Earth Sciences

Science.gov (United States)

Lehnert, K. A.; Goldstein, S. L.; Lenhardt, C.; Vinayagamoorthy, S.

2004-12-01

The study of solid earth samples is key to our knowledge of Earth's dynamical systems and evolution. The data generated provide the basis for models and hypotheses in all disciplines of the Geosciences from tectonics to magmatic processes to mantle dynamics to paleoclimate research. Sample-based data are diverse ranging from major and trace element abundances, radiogenic and stable isotope ratios of rocks, minerals, fluid or melt inclusions, to age determinations and descriptions of lithology, texture, mineral or fossil content, stratigraphic context, physical properties. The usefulness of these data is critically dependent on their integration as a coherent data set for each sample. If different data sets for the same sample cannot be combined because the sample cannot be unambiguously recognized, valuable information is lost. The ambiguous naming of samples has been a major problem in the geosciences. Different samples are often given identical names, and there is a tendency for different people analyzing the same sample to rename it in their publications according to local conventions. This situation has generated significant confusion, with samples often losing their "history", making it difficult or impossible to link available data. This has become most evident through the compilation of geochemical data in relational databases such as PetDB, NAVDAT, and GEOROC. While the relational data structure allows linking of disparate data for samples published in different references, linkages cannot be established due to ambiguous sample names. SESAR is a response to this problem of ambiguous naming of samples. SESAR will create a common clearinghouse that provides a centralized registry of sample identifiers, to avoid ambiguity, to systematize sample designation, and ensure that all information associated with a sample would in fact be unique. The project will build a web-based digital registry for solid earth samples that will provide for the first time a way to

Tight multilattices calculated by extended-cell cylindrization

Energy Technology Data Exchange (ETDEWEB)

Segev, M; Carmona, S

1983-01-01

Among the common features of advanced LWR concepts are the tightness of lattices and the symbiotic setting of different fuels. Such symbioses often come in the form of multilattices, whose numerically-repeated unit is a configuration of several pins, typically with one pin type at the center and pins of a second type surrounding the center pin. If this extended-cell (EC) unit is cylindricized, then a simple transport calculation of the unit will be possible. If the lattice of such units is tight, there is further an a priori reason to expect the cylindrization to introduce only a small distortion of the true neutron fluxes in the lattice. A strict numerical validation of the EC cylindrization approximation is impractical, but similar validations can be carried out for regular lattices, viewed as being made up of multicell units whose centers are moderators and whose peripheries are fuel pins. In these comparisons the EC cylindrization approximation gives good results.

Scattering of spermatozoa off cylindrical pillars

Science.gov (United States)

Bukatin, Anton; Lushi, Enkeleida; Kantsler, Vasily

2017-11-01

The motion of micro-swimmers in structured environments, even though crucial in processes such as in vivo and in vitro egg fertilization, is still not completely understood. We combine microfluidic experiments with mathematical modeling of 3D swimming near convex surfaces to quantify the dynamics of individual sperm cells in the proximity of cylindrical pillars. Our results show that the hydrodynamic and contact forces that account for the shape asymmetry and flagellar motion, are crucial in correctly describing the dynamics observed in the experiments. Last, we discuss how the size of the cylindrical obstacles determines whether the swimmers scatter off or get trapped circling the pillar.

Determination of lead in rice grains by solid sampling HR-CS GFAAS.

Science.gov (United States)

Gunduz, Sema; Akman, Suleyman

2013-12-01

A study was performed for the determination of lead in rice grains directly by solid sampling high resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) without digesting sample. The effects of sample amount, pyrolysis/atomization temperatures on the determination of lead in rice were investigated and optimized using a certificated rice flour. The lead concentrations were determined applying 800 °C of pyrolysis and 1800 °C of atomization temperatures without modifier. LOD (N=10, 3σ) and characteristic mass were 2.3 μg kg(-1) and 8.1 pg, respectively. The certified lead value of a rice flour CRM was found in its uncertainity limits. The lead contents of various rice samples obtained from markets in Turkey were between 0.009 and 0.162 mg kg(-1) which are in acceptable range. The average lead concentrations in various rice grains taken from the same package were significantly different from each other. Copyright © 2013 Elsevier Ltd. All rights reserved.

On-line determination of manganese in solid seafood samples by flame atomic absorption spectrometry

International Nuclear Information System (INIS)

Yebra, M.C.; Moreno-Cid, A.

2003-01-01

Manganese is extracted on-line from solid seafood samples by a simple continuous ultrasound-assisted extraction system (CUES). This system is connected to an on-line manifold, which permits the flow-injection flame atomic absorption spectrometric determination of manganese. Optimisation of the continuous leaching procedure is performed by an experimental design. The proposed method allows the determination of manganese with a relative standard deviation of 0.9% for a sample containing 23.4 μg g -1 manganese (dry mass). The detection limit is 0.4 μg g -1 (dry mass) for 30 mg of sample and the sample throughput is ca. 60 samples per hour. Accurate results are obtained by measuring TORT-1 certified reference material. The procedure is finally applied to mussel, tuna, sardine and clams samples

Implosion of multilayered cylindrical targets driven by intense heavy ion beams.

Science.gov (United States)

Piriz, A R; Portugues, R F; Tahir, N A; Hoffmann, D H H

2002-11-01

An analytical model for the implosion of a multilayered cylindrical target driven by an intense heavy ion beam has been developed. The target is composed of a cylinder of frozen hydrogen or deuterium, which is enclosed in a thick shell of solid lead. This target has been designed for future high-energy-density matter experiments to be carried out at the Gesellschaft für Schwerionenforschung, Darmstadt. The model describes the implosion dynamics including the motion of the incident shock and the first reflected shock and allows for calculation of the physical conditions of the hydrogen at stagnation. The model predicts that the conditions of the compressed hydrogen are not sensitive to significant variations in target and beam parameters. These predictions are confirmed by one-dimensional numerical simulations and thus allow for a robust target design.

Two-dimensional collapse calculations of cylindrical clouds

International Nuclear Information System (INIS)

Bastien, P.; Mitalas, R.

1979-01-01

A two-dimensional hydrodynamic computer code has been extensively modified and expanded to study the collapse of non-rotating interstellar clouds. The physics and the numerical methods involved are discussed. The results are presented and discussed in terms of the Jeans number. The critical Jeans number for collapse of non-rotating cylindrical clouds whose length is the same as their diameter is 1.00. No evidence for fragmentation has been found for these clouds, but fragmentation seems quite likely for more elongated cylindrical clouds. (author)

Fluid sampling tool

Science.gov (United States)

Garcia, A.R.; Johnston, R.G.; Martinez, R.K.

1999-05-25

A fluid sampling tool is described for sampling fluid from a container. The tool has a fluid collecting portion which is drilled into the container wall, thereby affixing it to the wall. The tool may have a fluid extracting section which withdraws fluid collected by the fluid collecting section. The fluid collecting section has a fluted shank with an end configured to drill a hole into a container wall. The shank has a threaded portion for tapping the borehole. The shank is threadably engaged to a cylindrical housing having an inner axial passageway sealed at one end by a septum. A flexible member having a cylindrical portion and a bulbous portion is provided. The housing can be slid into an inner axial passageway in the cylindrical portion and sealed to the flexible member. The bulbous portion has an outer lip defining an opening. The housing is clamped into the chuck of a drill, the lip of the bulbous section is pressed against a container wall until the shank touches the wall, and the user operates the drill. Wall shavings (kerf) are confined in a chamber formed in the bulbous section as it folds when the shank advances inside the container. After sufficient advancement of the shank, an o-ring makes a seal with the container wall. 6 figs.

Solid polymer electrolyte composite membrane comprising plasma etched porous support

Science.gov (United States)

Liu, Han; LaConti, Anthony B.

2010-10-05

A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 0.1 to 5 microns, are made by plasma etching and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

Solid polymer electrolyte composite membrane comprising laser micromachined porous support

Science.gov (United States)

Liu, Han [Waltham, MA; LaConti, Anthony B [Lynnfield, MA; Mittelsteadt, Cortney K [Natick, MA; McCallum, Thomas J [Ashland, MA

2011-01-11

A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a rigid, non-electrically-conducting support, the support preferably being a sheet of polyimide having a thickness of about 7.5 to 15 microns. The support has a plurality of cylindrical pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores, which preferably have a diameter of about 5 microns, are made by laser micromachining and preferably are arranged in a defined pattern, for example, with fewer pores located in areas of high membrane stress and more pores located in areas of low membrane stress. The pores are filled with a first solid polymer electrolyte, such as a perfluorosulfonic acid (PFSA) polymer. A second solid polymer electrolyte, which may be the same as or different than the first solid polymer electrolyte, may be deposited over the top and/or bottom of the first solid polymer electrolyte.

Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

International Nuclear Information System (INIS)

Edjabou, Maklawe Essonanawe; Jensen, Morten Bang; Götze, Ramona; Pivnenko, Kostyantyn; Petersen, Claus; Scheutz, Charlotte; Astrup, Thomas Fruergaard

2015-01-01

Highlights: • Tiered approach to waste sorting ensures flexibility and facilitates comparison of solid waste composition data. • Food and miscellaneous wastes are the main fractions contributing to the residual household waste. • Separation of food packaging from food leftovers during sorting is not critical for determination of the solid waste composition. - Abstract: Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10–50 waste fractions, organised according to a three-level (tiered approach) facilitating comparison of the waste data between individual sub-areas with different fractionation (waste from one municipality was sorted at “Level III”, e.g. detailed, while the two others were sorted only at “Level I”). The results showed that residual household waste mainly contained food waste (42 ± 5%, mass per wet basis) and miscellaneous combustibles (18 ± 3%, mass per wet basis). The residual household waste generation rate in the study areas was 3–4 kg per person per week. Statistical analyses revealed that the waste composition was independent of variations in the waste generation rate. Both, waste composition and waste generation rates were statistically similar for each of the three municipalities. While the waste generation rates were similar for each of the two housing types (single

Municipal solid waste composition: Sampling methodology, statistical analyses, and case study evaluation

Energy Technology Data Exchange (ETDEWEB)

Edjabou, Maklawe Essonanawe, E-mail: vine@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Jensen, Morten Bang; Götze, Ramona; Pivnenko, Kostyantyn [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Petersen, Claus [Econet AS, Omøgade 8, 2.sal, 2100 Copenhagen (Denmark); Scheutz, Charlotte; Astrup, Thomas Fruergaard [Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

2015-02-15

Highlights: • Tiered approach to waste sorting ensures flexibility and facilitates comparison of solid waste composition data. • Food and miscellaneous wastes are the main fractions contributing to the residual household waste. • Separation of food packaging from food leftovers during sorting is not critical for determination of the solid waste composition. - Abstract: Sound waste management and optimisation of resource recovery require reliable data on solid waste generation and composition. In the absence of standardised and commonly accepted waste characterisation methodologies, various approaches have been reported in literature. This limits both comparability and applicability of the results. In this study, a waste sampling and sorting methodology for efficient and statistically robust characterisation of solid waste was introduced. The methodology was applied to residual waste collected from 1442 households distributed among 10 individual sub-areas in three Danish municipalities (both single and multi-family house areas). In total 17 tonnes of waste were sorted into 10–50 waste fractions, organised according to a three-level (tiered approach) facilitating comparison of the waste data between individual sub-areas with different fractionation (waste from one municipality was sorted at “Level III”, e.g. detailed, while the two others were sorted only at “Level I”). The results showed that residual household waste mainly contained food waste (42 ± 5%, mass per wet basis) and miscellaneous combustibles (18 ± 3%, mass per wet basis). The residual household waste generation rate in the study areas was 3–4 kg per person per week. Statistical analyses revealed that the waste composition was independent of variations in the waste generation rate. Both, waste composition and waste generation rates were statistically similar for each of the three municipalities. While the waste generation rates were similar for each of the two housing types (single

Solid Phase Microextraction (SPME in Determination of Pesticide Residues in Soil Samples

Directory of Open Access Journals (Sweden)

Rada Đurović

2011-01-01

Full Text Available The basic principles and application possibilities of the methods based on solid phase microextraction (SPME in the analysis of pesticide residues in soil samples are presented in the paper. The most important experimental parameters which affect SPME efficacy inpesticide determination (type and thickness of microextraction fiber, duration of microextraction,temperature at which it is conducted, effect of addition of salts (the effect of efflorescence,temperature and time of desorption, the choice of optimal solvent for pesticide exctraction from the soil and the optimal number of extraction steps, as well as general guidelines for their optimization are also shown. In the end, current applications of SPMEmethods in the analysis of pesticide residues in soil samples are presented.

Rotation, inversion and perversion in anisotropic elastic cylindrical tubes and membranes

KAUST Repository

Goriely, A.

2013-03-06

Cylindrical tubes and membranes are universal structural elements found in biology and engineering over a wide range of scales.Working in the framework of nonlinear elasticity, we consider the possible deformations of elastic cylindrical shells reinforced by one or two families of fibres. We consider both small and large deformations and the reduction from thick cylindrical shells (tubes) to thin shells (cylindrical membranes). In particular, a number of universal parameter regimes can be identified where the response behaviour of the cylinder is qualitatively different. This include the possibility of inversion of twist or axial strain when the cylinder is subject to internal pressure. Copyright © The Royal Society 2013.

Buckling measurement in the IPEN/MB-01 nuclear reactor in cylindrical configuration of minor excess of reactivity

Energy Technology Data Exchange (ETDEWEB)

Purgato, Rafael Turrini; Bitelli, Ulysses d' Utra; Aredes, Vitor Ottoni; Silva, Alexandre F. Povoa da; Santos, Diogo Feliciano dos; Lima, Ana Cecilia de Souza, E-mail: ubitelli@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

This work presents the results of experimental Buckling in the IPEN/MB-01 nuclear reactor in its cylindrical configuration with 28 fuel rods along its diameter. The IPEN/MB-01 is a zero power reactor designed to operate at a maximum power of 100 watts. It is a versatile nuclear facility, which allows for the simulation of all the characteristics of a nuclear power reactor making it an ideal test bed for this kind of measurement. A mapping of neutron flux inside the reactor is carried out in order to determine the total Buckling of the cylindrical configuration. The reactor was operated for one hour. Then, the activity of the fuel rods is measured by gamma ray spectrometry using a HPGe solid state detector and a suitable rod scanner. Photon energies of 276.6keV from {sup 239}Np (neutron capture (n,?) nuclear reaction) and 293.3keV from {sup 143}Ce (fission (n,f) nuclear reaction on both {sup 238}U and {sup 235}U) , are respectively along both axial and radial directions. Other measurements are performed using gold wires and foils along radial and axial directions of the reactor core. The three methods above resulted in a weighted average value of 93.18 ± 8.47 m-2 for the Total Buckling of this cylindrical core configuration with 28 control rods along its diameter with 568 fuel rods and only 271 pcm of excess reactivity. (author)

Confined detonations with cylindrical and spherical symmetry; Detonaciones confinadas con simetria esferica y cilindrica

Energy Technology Data Exchange (ETDEWEB)

Linan, A; Lecuona, A

1979-07-01

An imploding spherical or cylindrical detonation, starting in the interface of the detonantion with an external inert media, used as a reflector, creates on it a strong shock wave moving outward from the interface. An initially weak shock wave appears in the detonated media that travels toward the center, and it could reach the detonation wave, enforcing it in its process of implosion. To describe the fluid field, the Euler s equations are solved by means of expansions valid for the early stages of the process. Isentropic of the type P/p{gamma}-K for the detonated and compressed inert media are used. For liquid or solid reflectors a more appropriate equation is used. (Author) 8 refs.

Application of the orthogonal collocation method to determination of temperature distribution in cylindrical conductors

International Nuclear Information System (INIS)

Fortini, Maria A.; Stamoulis, Michel N.; Ferreira, Angela F.M.; Pereira, Claubia; Costa, Antonella L.; Silva, Clarysson A.M.

2008-01-01

In this work, an analytical model for the determination of the temperature distribution in cylindrical heater components with characteristics of nuclear fuel rods, is presented. The heat conductor is characterized by an arbitrary number of solid walls and different types of materials, whose thermal properties are taken as function of temperature. The heat conduction fundamental equation is solved numerically with the method of weighted residuals (MWR) using a technique of orthogonal collocation. The results obtained with the proposed method are compared with the experimental data from tests performed in the TRIGA IPR-R1 research reactor localized at the CDTN/CNEN (Centro de Desenvolvimento da Tecnologia Nuclear/Comissao Nacional de Energia Nuclear) at Belo Horizonte in Brazil

A numerical study of wave dispersion curves in cylindrical rods with circular cross-section

Directory of Open Access Journals (Sweden)

Valsamos G.

2013-06-01

Full Text Available This work presents a finite element approach for modeling longitudinal wave propagation in thick cylindrical rods with circular cross-section. The formulation is based on simple time domain response of the structure to a properly chosen excitation, and is calculated with an explicit finite element solver. The proposed post-treatment procedure identifies the wavenumber for each mode of wave propagation at the desired frequency. The procedure is implemented and integrated in an efficient way in the explicit finite element code Europlexus. The numerical results are compared to the analytical ones obtained from the solution of the Pochhammer — Chree equation, which provides the dispersion curves for wavetrains in solid cylinders of infinite length.

Axially symmetrical stresses measurement in the cylindrical tube using DIC with hole-drilling

Science.gov (United States)

Ma, Yinji; Yao, Xuefeng; Zhang, Danwen

2015-03-01

In this paper, a new method combining the digital image correlation (DIC) with the hole-drilling technology to characterize the axially symmetrical stresses of the cylindrical tube is developed. First, the theoretical expressions of the axially symmetrical stresses in the cylindrical tube are derived based on the displacement or strain fields before and after hole-drilling. Second, the release of the axially symmetrical stresses for the cylindrical tube caused by hole-drilling is simulated by the finite element method (FEM), which indicates that the axially symmetrical stresses of the cylindrical tube calculated by the cylindrical solution is more accuracy than that for traditionally planar solution. Finally, both the speckle image information and the displacement field of the cylindrical tube before and after hole-drilling are extracted by combining the DIC with the hole-drilling technology, then the axially symmetrical loading induced stresses of the cylindrical tube are obtained, which agree well with the results from the strain gauge method.

Antibubbles and fine cylindrical sheets of air

KAUST Repository

Beilharz, D.

2015-08-14

Drops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a higher-viscosity drop onto a lower-viscosity pool, we have explored new geometries of such air films. In this way we are able to maintain stable air layers which can wrap around the entire drop to form repeatable antibubbles, i.e. spherical air layers bounded by inner and outer liquid masses. Furthermore, for the most viscous drops they enter the pool trailing a viscous thread reaching all the way to the pinch-off nozzle. The air sheet can also wrap around this thread and remain stable over an extended period of time to form a cylindrical air sheet. We study the parameter regime where these structures appear and their subsequent breakup. The stability of these thin cylindrical air sheets is inconsistent with inviscid stability theory, suggesting stabilization by lubrication forces within the submicron air layer. We use interferometry to measure the air-layer thickness versus depth along the cylindrical air sheet and around the drop. The air film is thickest above the equator of the drop, but thinner below the drop and up along the air cylinder. Based on microbubble volumes, the thickness of the cylindrical air layer becomes less than 100 nm before it ruptures.

Antibubbles and fine cylindrical sheets of air

KAUST Repository

Beilharz, D.; Guyon, A.; Li, E.  Q.; Thoraval, M.-J.; Thoroddsen, Sigurdur T

2015-01-01

Drops impacting at low velocities onto a pool surface can stretch out thin hemispherical sheets of air between the drop and the pool. These air sheets can remain intact until they reach submicron thicknesses, at which point they rupture to form a myriad of microbubbles. By impacting a higher-viscosity drop onto a lower-viscosity pool, we have explored new geometries of such air films. In this way we are able to maintain stable air layers which can wrap around the entire drop to form repeatable antibubbles, i.e. spherical air layers bounded by inner and outer liquid masses. Furthermore, for the most viscous drops they enter the pool trailing a viscous thread reaching all the way to the pinch-off nozzle. The air sheet can also wrap around this thread and remain stable over an extended period of time to form a cylindrical air sheet. We study the parameter regime where these structures appear and their subsequent breakup. The stability of these thin cylindrical air sheets is inconsistent with inviscid stability theory, suggesting stabilization by lubrication forces within the submicron air layer. We use interferometry to measure the air-layer thickness versus depth along the cylindrical air sheet and around the drop. The air film is thickest above the equator of the drop, but thinner below the drop and up along the air cylinder. Based on microbubble volumes, the thickness of the cylindrical air layer becomes less than 100 nm before it ruptures.

Sampling of tar from sewage sludge gasification using solid phase adsorption.

Science.gov (United States)

Ortiz González, Isabel; Pérez Pastor, Rosa Ma; Sánchez Hervás, José Ma

2012-06-01

Sewage sludge is a residue from wastewater treatment plants which is considered to be harmful to the environment and all living organisms. Gasification technology is a potential source of renewable energy that converts the sewage sludge into gases that can be used to generate energy or as raw material in chemical synthesis processes. But tar produced during gasification is one of the problems for the implementation of the gasification technology. Tar can condense on pipes and filters and may cause blockage and corrosion in the engines and turbines. Consequently, to minimize tar content in syngas, the ability to quantify tar levels in process streams is essential. The aim of this work was to develop an accurate tar sampling and analysis methodology using solid phase adsorption (SPA) in order to apply it to tar sampling from sewage sludge gasification gases. Four types of commercial SPA cartridges have been tested to determine the most suitable one for the sampling of individual tar compounds in such streams. Afterwards, the capacity, breakthrough volume and sample stability of the Supelclean™ ENVI-Carb/NH(2), which is identified as the most suitable, have been determined. Basically, no significant influences from water, H(2)S or NH(3) were detected. The cartridge was used in sampling real samples, and comparable results were obtained with the present and traditional methods.

Plasma immersion ion implantation of the interior surface of a large cylindrical bore using an auxiliary electrode

International Nuclear Information System (INIS)

Zeng, X.C.; Kwok, T.K.; Liu, A.G.; Chu, P.K.; Tang, B.Y.

1998-01-01

A model utilizing cold, unmagnetized, and collisionless fluid ions as well as Boltzmann electrons is used to comprehensively investigate the sheath expansion into a translationally invariant large bore in the presence of an auxiliary electrode during plasma immersion ion implantation (PIII) of a cylindrical bore sample. The governing equation of ion continuity, ion motion, and Poisson close-quote s equation are solved by using a numerical finite difference method for different cylindrical bore radii, auxiliary electrode radii, and voltage rise times. The ion density and ion impact energy at the cylindrical inner surface, as well as the ion energy distribution, maximum ion impact energy, and average ion impact energy for the various cases are obtained. Our results show a dramatic improvement in the impact energy when an auxiliary electrode is used and the recommended normalized auxiliary electrode radius is in the range of 0.1 endash 0.3. copyright 1998 American Institute of Physics

Cylindrical pressure vessel constructed of several layers

International Nuclear Information System (INIS)

Yamauchi, Takeshi.

1976-01-01

For a cylindrical pressure vessel constructed of several layers whose jacket has at least one circumferential weld joining the individual layers, it is proposed to provide this at least at the first bending line turning point (counting from the weld between the jacket and vessel floor), which the sinusoidally shaped jacket has. The section of the jacket extending in between should be made as a full wall section. The proposal is based on calculations of the bending stiffness of cylindrical jackets, which could not yet be confirmed for jackets having several layers. (UWI) [de

Novel spherical hohlraum with cylindrical laser entrance holes and shields

Energy Technology Data Exchange (ETDEWEB)

Lan, Ke [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Center for Applied Physics and Technology, Peking University, Beijing 100871 (China); Zheng, Wudi [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)

2014-09-15

Our recent works [K. Lan et al., Phys. Plasmas 21, 010704 (2014); K. Lan et al., Phys. Plasmas 21, 052704 (2014)] have shown that the octahedral spherical hohlraums are superior to the cylindrical hohlraums in both higher symmetry during the capsule implosion and lower backscatter without supplementary technology. However, both the coupling efficiency from the drive laser energy to the capsule and the capsule symmetry decrease remarkably when larger laser entrance holes (LEHs) are used. In addition, the laser beams injected at angles > 45° transport close to the hohlraum wall, thus the wall blowoff causes the LEH to close faster and results in strong laser plasma interactions inside the spherical hohlraums. In this letter, we propose a novel octahedral hohlraum with LEH shields and cylindrical LEHs to alleviate these problems. From our theoretical study, with the LEH shields, the laser coupling efficiency is significantly increased and the capsule symmetry is remarkably improved in the spherical hohlraums. The cylindrical LEHs take advantage of the cylindrical hohlraum near the LEH and mitigate the influence of the blowoff on laser transport inside a spherical hohlraum. The cylindrical LEHs can also be applied to the rugby and elliptical hohlraums.

Novel spherical hohlraum with cylindrical laser entrance holes and shields

International Nuclear Information System (INIS)

Lan, Ke; Zheng, Wudi

2014-01-01

Our recent works [K. Lan et al., Phys. Plasmas 21, 010704 (2014); K. Lan et al., Phys. Plasmas 21, 052704 (2014)] have shown that the octahedral spherical hohlraums are superior to the cylindrical hohlraums in both higher symmetry during the capsule implosion and lower backscatter without supplementary technology. However, both the coupling efficiency from the drive laser energy to the capsule and the capsule symmetry decrease remarkably when larger laser entrance holes (LEHs) are used. In addition, the laser beams injected at angles > 45° transport close to the hohlraum wall, thus the wall blowoff causes the LEH to close faster and results in strong laser plasma interactions inside the spherical hohlraums. In this letter, we propose a novel octahedral hohlraum with LEH shields and cylindrical LEHs to alleviate these problems. From our theoretical study, with the LEH shields, the laser coupling efficiency is significantly increased and the capsule symmetry is remarkably improved in the spherical hohlraums. The cylindrical LEHs take advantage of the cylindrical hohlraum near the LEH and mitigate the influence of the blowoff on laser transport inside a spherical hohlraum. The cylindrical LEHs can also be applied to the rugby and elliptical hohlraums

Development of a portable mass spectrometric system for determination of isotopic composition of solid uranium samples using fluorine volatilization

Science.gov (United States)

Loge, G.

1994-09-01

Using hardware and materials supplied by LANL, a prototype quadrupole mass spectrometer system designed for portable field analysis of isotopic composition of solid uranium samples was assembled and tested. The system contained the capability for fluorine volatilization of solid uranium samples with gas introduction, which was successfully tested and demonstrated using 100 mg samples of U3O8. Determination of precision and accuracy for measuring isotopic composition was performed using isotopic standards. Use with soil samples containing uranium were also attempted. Silicates in the soil forming SiF4 were found to be a kinetic bottleneck to the formation of UF6. This could be avoided by performing some sort of chemical separation as a pre-treatment step, which was demonstrated using nitric acid.

Solid sampling-graphite furnace atomic absorption spectrometry for the direct determination of boron in plant tissues

International Nuclear Information System (INIS)

Resano, M.; Briceno, J.; Aramendia, M.; Belarra, M.A.

2007-01-01

In this work, the potential of graphite furnace atomic absorption spectrometry for the direct determination of B in plant tissues has been investigated. Three certified reference materials (NIST SRM 1570a spinach leaves, NIST SRM 1573a tomato leaves and BCR CRM 679 white cabbage) were selected for this study, the goal always being to develop a fast procedure that could be robust enough to provide a satisfactory performance for all of them, without any modifications in the conditions applied. The use of a suitable chemical modifier was found to be essential for obtaining a reproducible and sufficiently sensitive signal for boron solutions. In this regard, the performance of the combination of citric acid plus W (added as a permanent modifier) was noteworthy, resulting in well-defined signal profiles, a remarkable analyte stabilization during the pyrolysis step (up to 2100 deg. C) and minimal memory effects. This mixture of modifiers provided a good performance for the direct analysis of solid samples as well, but only if a suitable temperature program, favoring the interaction between the analyte and the modifiers, was used. Thus, such a temperature program, with two pyrolysis steps and the addition of NH 4 NO 3 in order to carry out the in situ sample microdigestion, was optimized. Under these conditions, the peak areas obtained for both solid samples and aqueous standards were comparable. Finally, the analysis of the samples was carried out. In all cases, a good agreement with the certified values was obtained, while R.S.D. values ranged between 6 and 10%. It can be concluded that the method proposed shows significant advantages for the determination of this complicated element in solid samples such as the use of aqueous standards for calibration, a high sample throughput (20 min per sample), a suitable limit of detection (0.3 μg g -1 ) and reduced risk of analyte losses and contamination

Cylindrical optical resonators: fundamental properties and bio-sensing characteristics

Science.gov (United States)

Khozeymeh, Foroogh; Razaghi, Mohammad

2018-04-01

In this paper, detailed theoretical analysis of cylindrical resonators is demonstrated. As illustrated, these kinds of resonators can be used as optical bio-sensing devices. The proposed structure is analyzed using an analytical method based on Lam's approximation. This method is systematic and has simplified the tedious process of whispering-gallery mode (WGM) wavelength analysis in optical cylindrical biosensors. By this method, analysis of higher radial orders of high angular momentum WGMs has been possible. Using closed-form analytical equations, resonance wavelengths of higher radial and angular order WGMs of TE and TM polarization waves are calculated. It is shown that high angular momentum WGMs are more appropriate for bio-sensing applications. Some of the calculations are done using a numerical non-linear Newton method. A perfect match of 99.84% between the analytical and the numerical methods has been achieved. In order to verify the validity of the calculations, Meep simulations based on the finite difference time domain (FDTD) method are performed. In this case, a match of 96.70% between the analytical and FDTD results has been obtained. The analytical predictions are in good agreement with other experimental work (99.99% match). These results validate the proposed analytical modelling for the fast design of optical cylindrical biosensors. It is shown that by extending the proposed two-layer resonator structure analyzing scheme, it is possible to study a three-layer cylindrical resonator structure as well. Moreover, by this method, fast sensitivity optimization in cylindrical resonator-based biosensors has been possible. Sensitivity of the WGM resonances is analyzed as a function of the structural parameters of the cylindrical resonators. Based on the results, fourth radial order WGMs, with a resonator radius of 50 μm, display the most bulk refractive index sensitivity of 41.50 (nm/RIU).

Simultaneous Effects of Total Solids Content, Milk Base, Heat Treatment Temperature and Sample Temperature on the Rheological Properties of Plain Stirred Yogurt

Directory of Open Access Journals (Sweden)

Attilio Converti

2006-01-01

Full Text Available Response surface methodology was used to establish a relationship between total solids content, milk base, heat treatment temperature, and sample temperature, and consistency index, flow behaviour index, and apparent viscosity of plain stirred yogurts. Statistical treatments resulted in developments of mathematical models. All samples presented shear thinning fluid behaviour. The increase of the content of total solids (9.3–22.7 % and milk base heat treatment temperature (81.6–98.4 °C resulted in a significant increase in consistency index and a decrease in flow behaviour index. Increase in the sample temperature (1.6–18.4 °C caused a decrease in consistency index and increase in flow behaviour index. Apparent viscosity was directly related to the content of total solids. Rheological properties of yogurt were highly dependent on the content of total solids in milk.

On cylindrically converging shock waves shaped by obstacles

Energy Technology Data Exchange (ETDEWEB)

Eliasson, V; Henshaw, W D; Appelo, D

2007-07-16

Motivated by recent experiments, numerical simulations were performed of cylindrically converging shock waves. The converging shocks impinged upon a set of zero to sixteen regularly space obstacles. For more than two obstacles the resulting diffracted shock fronts formed polygonal shaped patterns near the point of focus. The maximum pressure and temperature as a function of number of obstacles were studied. The self-similar behavior of cylindrical, triangular and square-shaped shocks were also investigated.

The study of flow and proton exchange interactions in the cylindrical solid oxide fuel cell

International Nuclear Information System (INIS)

Saievar-Iranizad, E.; Malekifar, A.

2002-01-01

The solid oxide fuel cell operates at high temperature of about 1000 deg C. In this temperature, some known materials such as Ni, ... which is abundant in the nature, can be used as a catalyst in the electrodes. The electrolytes of such cell solid oxide fuel cell can be made through non-porous solid ceramics such as Zircon's (ZrO 2 ). It can be stabilized using a doped Yttrium oxide. The importance of Yttria-stabilised Zirconia at high temperature belongs to the transport of oxygen ions through the electrolyte. Oxygen using in the hot cathode side causes a considerable reduction in the concentration of oxygen molecules. The oxygen ions exchange through the electrolyte relates to the molecular oxygen concentration gradient between the anode and cathode. Applying fuels such as hydrogen or natural gas in the anode and its chemical reaction with oxygen ions transfer from cathode through the electrolyte, produce electricity, water and heat. To study the ion exchange and its interaction into solid oxide fuel cell, a mathematical model had been considered in this article. This model simulates and illustrates the interaction, diffusion and oxygen ions exchange into fuel cell. The electrical power of fuel cell due to the ion exchange can be obtained using a simulation method. The ion exchange simulation, diffusion of molecules, their interactions and system development through the mathematical model has been discussed in this paper

Dismantling OPAL's cylindrical magnet core

CERN Multimedia

Laurent Guiraud

2001-01-01

Lifting a handling device for dismounting the pressure bells, which are inside the cylindrical magnet coil on the central section of OPAL, on the right part of the photo. OPAL was a detector on the LEP accelerator, which ran from 1989 to 2000.

Direct determination of cadmium in foods by solid sampling electrothermal vaporization inductively coupled plasma mass spectrometry using a tungsten coil trap

Science.gov (United States)

Zhang, Ying; Mao, Xuefei; Liu, Jixin; Wang, Min; Qian, Yongzhong; Gao, Chengling; Qi, Yuehan

2016-04-01

In this work, a solid sampling device consisting of a tungsten coil trap, porous carbon vaporizer and on-line ashing furnace of a Ni-Cr coil was interfaced with inductively coupled plasma mass spectrometry (ICP-MS). A modified double gas circuit system was employed that was composed of carrier and supplemental gas lines controlled by separate gas mass flow controllers. For Cd determination in food samples using the assembled solid sampling ICP-MS, the optimal ashing and vaporization conditions, flow rate of the argon-hydrogen (Ar/H2) (v:v = 24:1) carrier gas and supplemental gas, and minimum sampling mass were investigated. Under the optimized conditions, the limit of quantification was 0.5 pg and the relative standard deviation was within a 10.0% error range (n = 10). Furthermore, the mean spiked recoveries for various food samples were 99.4%-105.9% (n = 6). The Cd concentrations measured by the proposed method were all within the certified values of the reference materials or were not significantly different (P > 0.05) from those of the microwave digestion ICP-MS method, demonstrating the good accuracy and precision of the solid sampling ICP-MS method for Cd determination in food samples.

Cylindric partitions, {{\\boldsymbol{ W }}}_{r} characters and the Andrews-Gordon-Bressoud identities

Science.gov (United States)

Foda, O.; Welsh, T. A.

2016-04-01

We study the Andrews-Gordon-Bressoud (AGB) generalisations of the Rogers-Ramanujan q-series identities in the context of cylindric partitions. We recall the definition of r-cylindric partitions, and provide a simple proof of Borodin’s product expression for their generating functions, that can be regarded as a limiting case of an unpublished proof by Krattenthaler. We also recall the relationships between the r-cylindric partition generating functions, the principal characters of {\\hat{{sl}}}r algebras, the {{\\boldsymbol{ M }}}r r,r+d minimal model characters of {{\\boldsymbol{ W }}}r algebras, and the r-string abaci generating functions, providing simple proofs for each. We then set r = 2, and use two-cylindric partitions to re-derive the AGB identities as follows. Firstly, we use Borodin’s product expression for the generating functions of the two-cylindric partitions with infinitely long parts, to obtain the product sides of the AGB identities, times a factor {(q;q)}∞ -1, which is the generating function of ordinary partitions. Next, we obtain a bijection from the two-cylindric partitions, via two-string abaci, into decorated versions of Bressoud’s restricted lattice paths. Extending Bressoud’s method of transforming between restricted paths that obey different restrictions, we obtain sum expressions with manifestly non-negative coefficients for the generating functions of the two-cylindric partitions which contains a factor {(q;q)}∞ -1. Equating the product and sum expressions of the same two-cylindric partitions, and canceling a factor of {(q;q)}∞ -1 on each side, we obtain the AGB identities.

Receiver calibration and the nonlinearity parameter measurement of thick solid samples with diffraction and attenuation corrections.

Science.gov (United States)

Jeong, Hyunjo; Barnard, Daniel; Cho, Sungjong; Zhang, Shuzeng; Li, Xiongbing

2017-11-01

This paper presents analytical and experimental techniques for accurate determination of the nonlinearity parameter (β) in thick solid samples. When piezoelectric transducers are used for β measurements, the receiver calibration is required to determine the transfer function from which the absolute displacement can be calculated. The measured fundamental and second harmonic displacement amplitudes should be modified to account for beam diffraction and material absorption. All these issues are addressed in this study and the proposed technique is validated through the β measurements of thick solid samples. A simplified self-reciprocity calibration procedure for a broadband receiver is described. The diffraction and attenuation corrections for the fundamental and second harmonics are explicitly derived. Aluminum alloy samples in five different thicknesses (4, 6, 8, 10, 12cm) are prepared and β measurements are made using the finite amplitude, through-transmission method. The effects of diffraction and attenuation corrections on β measurements are systematically investigated. When diffraction and attenuation corrections are all properly made, the variation of β between different thickness samples is found to be less than 3.2%. Copyright © 2017 Elsevier B.V. All rights reserved.

Observation of unusual irreversible/reversible effects in a macroscopic cylindrical hole drilled in superconducting Bi-Sr-Ca-Cu-O

International Nuclear Information System (INIS)

Yetis, H.; Kilic, A.; Kilic, K.; Altinkok, A.; Olutas, M.

2008-01-01

Current-voltage (I-V) measurements were carried out for different current sweep rates (dI/dt) of transport current at zero magnetic field (H = 0) and H ≠ 0 in a polycrystalline sample of Bi 1.7 Pb 0.3 Sr 2 Ca 2 Cu 3 O x (BSCCO) with a macroscopic cylindrical hole (CH) drilled. Similar measurements were also performed in the same BSCCO sample without CH for a comparison before drilling CH. For the same values of H, T, and dI/dt taken for both samples, it was observed that hysteresis effects appear in I-V curves upon cycling of transport current in upward and downward directions which contain the increasing and decreasing current values, respectively. However these effects which are seen in I-V curves of BSCCO sample with CH is more prominent than that of the BSCCO sample without CH. Further, the irreversibility effects in I-V curves of the BSCCO sample without CH disappears for H ≠ 0 exhibiting nearly a linear behaviour, whereas the hysteretic behaviour in I-V curves of the BSCCO sample with CH is still observed. This interesting behaviour could be evaluated that macroscopic cylindrical hole improves pinning properties of sample acting as a macroscopic flux pinning center for flux lines

Micropatterning on cylindrical surfaces via electrochemical etching using laser masking

International Nuclear Information System (INIS)

Cho, Chull Hee; Shin, Hong Shik; Chu, Chong Nam

2014-01-01

Highlights: • Various micropatterns were fabricated on the cylindrical surface of a stainless steel shaft. • Selective electrochemical dissolution was achieved via a series process of laser masking and electrochemical etching. • Laser masking characteristics on the non-planar surface were investigated. • A uniform mask layer was formed on the cylindrical surface via synchronized laser line scanning with a rotary system. • The characteristics of electrochemical etching on the non-planar surface were investigated. - Abstract: This paper proposes a method of selective electrochemical dissolution on the cylindrical surfaces of stainless steel shafts. Selective electrochemical dissolution was achieved via electrochemical etching using laser masking. A micropatterned recast layer was formed on the surface via ytterbium-doped pulsed fiber laser irradiation. The micropatterned recast layer could be used as a mask layer during the electrochemical etching process. Laser masking condition to form adequate mask layer on the planar surface for etching cannot be used directly on the non-planar surface. Laser masking condition changes depending on the morphological surface. The laser masking characteristics were investigated in order to form a uniform mask layer on the cylindrical surface. To minimize factors causing non-uniformity in the mask layer on the cylindrical surface, synchronized laser line scanning with a rotary system was applied during the laser masking process. Electrochemical etching characteristics were also investigated to achieve deeper etched depth, without collapsing the recast layer. Consequently, through a series process of laser masking and electrochemical etching, various micropatternings were successfully performed on the cylindrical surfaces

Forced vibrations of rotating circular cylindrical shells

International Nuclear Information System (INIS)

Igawa, Hirotaka; Maruyama, Yoshiyuki; Endo, Mitsuru

1995-01-01

Forced vibrations of rotating circular cylindrical shells are investigated. Basic equations, including the effect of initial stress due to rotation, are formulated by the finite-element method. The characteristic relations for finite elements are derived from the energy principle by considering the finite strain. The equations of motion can be separated into quasi-static and dynamic ones, i.e., the equations in the steady rotating state and those in the vibration state. Radial concentrated impulses are considered as the external dynamic force. The transient responses of circular cylindrical shells are numerically calculated under various boundary conditions and rotating speeds. (author)

Vibrational analysis of submerged cylindrical shells based on elastic foundations

International Nuclear Information System (INIS)

Shah, A.G.; Naeem, M.N.

2014-01-01

In this study a vibration analysis was performed of an isotropic cylindrical shell submerged in fluid, resting on Winkler and Pasternak elastic foundations for simply supported boundary condition. Love's thin shell theory was exploited for strain- and curvature- displacement relationship. Shell problem was solved by using wave propagation approach. Influence of fluid and Winkler as well as Pasternak elastic foundations were studied on the natural frequencies of submerged isotropic cylindrical shells. Results were validated by comparing with the existing results in literature. Vibration, Submerged cylindrical shell, Love's thin shell theory, Wave propagation method, Winkler and Pasternak foundations. (author)

Cylindrical thin-shell wormholes

International Nuclear Information System (INIS)

Eiroa, Ernesto F.; Simeone, Claudio

2004-01-01

A general formalism for the dynamics of nonrotating cylindrical thin-shell wormholes is developed. The time evolution of the throat is explicitly obtained for thin-shell wormholes whose metric has the form associated with local cosmic strings. It is found that the throat collapses to zero radius, remains static, or expands forever, depending only on the sign of its initial velocity

Headspace Solid Phase Microextraction in Pesticide Residues Analysis: 2. Apple Samples

Directory of Open Access Journals (Sweden)

Jelena Milinović

2007-01-01

Full Text Available Headspace solid phase microextraction method (HS/SPME, optimised previously for pesticide water solutions, was applied to trace residues of the pesticides chlorpyrifos, fenthion and bifenthrin in apple samples. One-hour extraction procedure was performed at 60oC extraction temperature. Nonpolar polydimethyl siloxane (PDMS fiber was used. Detection and quantification were carried out by gas chromatography/mass spectrometry (GC/MS. A non-pesticide treated apple sample was fortified with the pesticides over a 0.025-1.25 mg/kg concentration range in order to determine analytical parameters of the method applied. Linearity with regression coefficient (R values higher than 0.99 were obtained over the whole concentration range investigated for chlorpyrifos and fenthion, while linear dependence was observed in the 0.1-1.25 mg/kg range for bifenthrin. Relative recovery values for samples fortified at different levels were in the 56.68-82.91% range. Limit of detection (LOD values were determined as follows: 0.014 mg/kg for chlorpyrifos, 0.021 mg/kg for fenthion and 0.053 mg/kg for bifenthrin. Relative standard deviation (RSD values obtained for multiple analysis of the sample fortified at 0.6 mg/kg level were not higher than 20%.

Formation of vortex breakdown in conical–cylindrical cavities

International Nuclear Information System (INIS)

Martins, Diego Alves de Moro; Souza, Francisco José de; Salvo, Ricardo de Vasconcelos

2014-01-01

Highlights: • Rotating flows in conical–cylindrical cavities were simulated via an in-house code using unstructured meshes. • The vortex breakdown phenomenon was verified in the geometries analyzed. • The influence of Stewartson and Bödewadt layers was observed in the vortex breakdown formation. • A curve of stability and number of breakdowns was obtained as a function of Reynolds number. • Spiral vortex breakdown was observed in some situations. - Abstract: Numerical simulations in confined rotating flows were performed in this work, in order to verify and characterize the formation of the vortex breakdown phenomenon. Cylindrical and conical–cylindrical geometries, both closed, were used in the simulations. The rotating flow is induced by the bottom wall, which rotates at constant angular velocity. Firstly the numerical results were compared to experimental results available in references, with the purpose to verify the capacity of the computational code to predict the vortex breakdown phenomenon. Further, several simulations varying the parameters which govern the characteristics of the flows analyzed in this work, i.e., the Reynolds number and the aspect ratio, were performed. In these simulations, the limits for the transitional regime and the vortex breakdown formation were verified. Steady and transient cases, with and without turbulence modeling, were simulated. In general, some aspects of the process of vortex breakdown in conical–cylindrical geometries were observed to be different from that in cylinders

The magnetic properties of the hollow cylindrical ideal remanence magnet

DEFF Research Database (Denmark)

Bjørk, Rasmus

2016-01-01

We consider the magnetic properties of the hollow cylindrical ideal remanence magnet. This magnet is the cylindrical permanent magnet that generates a uniform field in the cylinder bore, using the least amount of magnetic energy to do so. The remanence distribution of this magnet is derived...

arXiv The new cylindrical GEM inner tracker of BESIII

CERN Document Server

Lavezzi, L.; Amoroso, A.; Ferroli, R. Baldini; Bertani, M.; Bettoni, D.; Bianchi, F.; Calcaterra, A.; Canale, N.; Capodiferro, M.; Carassiti, V.; Cerioni, S.; Chai, Jy; Chiozzi, S.; Cibinetto, G.; Cossio, F.; Cotta Ramusino, A.; De Mori, F.; Destefanis, M.; Dong, J.; Evangelisti, F.; Farinelli, R.; Fava, L.; Felici, G.; Fioravanti, E.; Garzia, I.; Gatta, M.; Greco, M.; Leng, Cy; Li, H.; Maggiora, M.; Malaguti, R.; Marcello, S.; Melchiorri, M.; Mezzadri, G.; Mignone, M.; Morello, G.; Pacetti, S.; Patteri, P.; Pellegrino, J.; Pelosi, A.; Rivetti, A.; Rolo,; Savrié, M.; Scodeggio, M.; Soldani, E.; Sosio, S.; Spataro, S.; Tskhadadze, E.; Verma, S.; Wheadon, R.; Yan, L.

2018-05-03

The Cylindrical GEM-Inner Tracker (CGEM-IT) is the upgrade of the internal tracking system of the BESIII experiment. It consists of three layers of cylindrically-shaped triple GEMs, with important innovations with respect to the existing GEM detectors, in order to achieve the best performance with the lowest material budget. It will be the first cylindrical GEM running with analog readout inside a 1T magnetic field. The simultaneous measurement of both the deposited charge and the signal time will permit to use a combination of two algorithms to evaluate the spatial position of the charged tracks inside the CGEM-IT: the charge centroid and the micro time projection chamber modes. They are complementary and can cope with the asymmetry of the electron avalanche when running in magnetic field and with non-orthogonal incident tracks. To evaluate the behaviour under different working settings, both planar chambers and the first cylindrical prototype have been tested during various test beams at CERN with 150 GeV/c...

Determination of Pu isotopic composition and 241Am by high resolution gamma spectrometry on solid samples

International Nuclear Information System (INIS)

Sarkar, Arnab; Paul, Sumana; Aggarwal, Suresh K.; Tomar, Bhupendra S.

2011-08-01

The present report gives a detailed account of the development of non-destructive assay technique using high resolution gamma-ray spectrometry (HRGS) for determination of plutonium (Pu) isotopic composition and the 241 Am content in solid Pu samples. Energy range 120-420 keV was used in this study. The methodology involves in situ relative efficiency calibration during the measurement process itself, to reduce the errors and increase the reliability of the method. Twenty solid Pu samples of power reactor and research reactor grade were analyzed by this method and the results were compared with those obtained by thermal ionization mass spectrometry. The accuracy of the final results depends strongly upon the accuracy of the available nuclear data (decay constant, gamma abundance etc.). MATLAB based programme was written to perform the analysis. A counting time of 4 hour was chosen for achieving good statistics on the results for samples having 100-200 mg of Pu. The attainable accuracy is found to be 0.5-1% for the fissile isotopes ( 239 Pu + 241 Pu) and 5-10% for 241 Am content. (author)

Micromagnetic simulations of cylindrical magnetic nanowires

KAUST Repository

Ivanov, Yurii P.; Chubykalo-Fesenko, O.

2015-01-01

This chapter reviews micromagnetic simulations of cylindrical magnetic nanowires and their ordered arrays. It starts with a description of the theoretical background of micromagnetism. The chapter discusses main magnetization reversal modes, domain

Filling of charged cylindrical capillaries

NARCIS (Netherlands)

Das, Siddhartha; Chanda, Sourayon; Eijkel, J.C.T.; Tas, N.R.; Chakraborty, Suman; Mitra, Sushanta K.

2014-01-01

We provide an analytical model to describe the filling dynamics of horizontal cylindrical capillaries having charged walls. The presence of surface charge leads to two distinct effects: It leads to a retarding electrical force on the liquid column and also causes a reduced viscous drag force because

Inorganic mass spectrometry of solid samples

International Nuclear Information System (INIS)

Adams, F.; Vertes, A.

1990-01-01

In this review some recent developments in the field of inorganic mass spectrometry of solids are described with special emphasis on the actual state of understanding of the ionization processes. It concentrates on the common characteristics of methods such as spark source-, laser-, secondary ion-, inductively coupled plasma- and glow discharge mass spectrometry. (orig.)

Rotation, inversion and perversion in anisotropic elastic cylindrical tubes and membranes

KAUST Repository

Goriely, A.; Tabor, M.

2013-01-01

Cylindrical tubes and membranes are universal structural elements found in biology and engineering over a wide range of scales.Working in the framework of nonlinear elasticity, we consider the possible deformations of elastic cylindrical shells

Discrete element method (DEM) simulations of stratified sampling during solid dosage form manufacturing.

Science.gov (United States)

Hancock, Bruno C; Ketterhagen, William R

2011-10-14

Discrete element model (DEM) simulations of the discharge of powders from hoppers under gravity were analyzed to provide estimates of dosage form content uniformity during the manufacture of solid dosage forms (tablets and capsules). For a system that exhibits moderate segregation the effects of sample size, number, and location within the batch were determined. The various sampling approaches were compared to current best-practices for sampling described in the Product Quality Research Institute (PQRI) Blend Uniformity Working Group (BUWG) guidelines. Sampling uniformly across the discharge process gave the most accurate results with respect to identifying segregation trends. Sigmoidal sampling (as recommended in the PQRI BUWG guidelines) tended to overestimate potential segregation issues, whereas truncated sampling (common in industrial practice) tended to underestimate them. The size of the sample had a major effect on the absolute potency RSD. The number of sampling locations (10 vs. 20) had very little effect on the trends in the data, and the number of samples analyzed at each location (1 vs. 3 vs. 7) had only a small effect for the sampling conditions examined. The results of this work provide greater understanding of the effect of different sampling approaches on the measured content uniformity of real dosage forms, and can help to guide the choice of appropriate sampling protocols. Copyright © 2011 Elsevier B.V. All rights reserved.

A new method for determining the uranium and thorium distribution in volcanic rock samples using solid state nuclear track detectors

International Nuclear Information System (INIS)

Misdaq, M.A.; Bakhchi, A.; Ktata, A.; Koutit, A.; Lamine, J.; Ait nouh, F.; Oufni, L.

2000-01-01

A method based on using solid state nuclear track detectors (SSNTD) CR- 39 and LR-115 type II and calculating the probabilities for the alpha particles emitted by the uranium and thorium series to reach and be registered on these films was utilized for uranium and thorium contents determination in various geological samples. The distribution of uranium and thorium in different volcanic rocks has been investigated using the track fission method. In this work, the uranium and thorium contents have been determined in different volcanic rock samples by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD). The mean critical angles of etching of the solid state nuclear track detectors utilized have been calculated. A petrographical study of the volcanic rock thin layers studied has been conducted. The uranium and thorium distribution inside different rock thin layers has been studied. The mechanism of inclusion of the uranium and thorium nuclei inside the volcanic rock samples studied has been investigated. (author)

Approximate determination of efficiency for activity measurements of cylindrical samples

Energy Technology Data Exchange (ETDEWEB)

Helbig, W [Nuclear Engineering and Analytics Rossendorf, Inc. (VKTA), Dresden (Germany); Bothe, M [Nuclear Engineering and Analytics Rossendorf, Inc. (VKTA), Dresden (Germany)

1997-03-01

Some calibration samples are necessary with the same geometrical parameters but of different materials, containing known activities A homogeniously distributed. Their densities are measured, their mass absorption coefficients may be unknown. These calibration samples are positioned in the counting geometry, for instance directly on the detector. The efficiency function {epsilon}(E) for each sample is gained by measuring the gamma spectra and evaluating all usable gamma energy peaks. From these {epsilon}(E) the common valid {epsilon}{sub geom}(E) will be deduced. For this purpose the functions {epsilon}{sub mu}(E) for these samples have to be established. (orig.)

Spin-wave propagation spectrum in magnetization-modulated cylindrical nanowires

Energy Technology Data Exchange (ETDEWEB)

Li, Zhi-xiong; Wang, Meng-ning; Nie, Yao-zhuang; Wang, Dao-wei; Xia, Qing-lin [School of Physics and Electronics, Central South University, Changsha 410083 (China); Tang, Wei [School of Physics and Electronics, Central South University, Changsha 410083 (China); Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Zeng, Zhong-ming [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Guo, Guang-hua, E-mail: guogh@mail.csu.edu.cn [School of Physics and Electronics, Central South University, Changsha 410083 (China)

2016-09-15

Spin-wave propagation in periodic magnetization-modulated cylindrical nanowires is studied by micromagnetic simulation. Spin wave scattering at the interface of two magnetization segments causes a spin-wave band structure, which can be effectively tuned by changing either the magnetization modulation level or the period of the cylindrical nanowire magnonic crystal. The bandgap width is oscillating with either the period or magnetization modulation due to the oscillating variation of the spin wave transmission coefficient through the interface of the two magnetization segments. Analytical calculation based on band theory is used to account for the micromagnetic simulation results. - Highlights: • A magnetization-modulated cylindrical nanowire magnonic crystal is proposed. • Propagating characteristics of spin waves in such magnonic crystal are studied. • Spin-wave spectra can be manipulated by changing modulation level and period.

Cylindrical concave body of composite fibrous material

International Nuclear Information System (INIS)

1979-01-01

The invention is concerned with a cylindrical concave body of compound fibrous material which is intended to be exposed to high rotation speeds around its own longitudinal axis. The concave body in question has at least one layer of fibrils that are interwoven and enclose an identical angle with the longitudinal axis of the concave body in both directions. The concave body in question also has at least a second layer of fibrils that run in the direction of the circumference and are fitted radially to the outside. The cylindrical concave body of the invention is particularly well suited for application as a rotor tube in a gas ultra-centrifuge

A Novel Vibration Mode Testing Method for Cylindrical Resonators Based on Microphones

Directory of Open Access Journals (Sweden)

Yongmeng Zhang

2015-01-01

Full Text Available Non-contact testing is an important method for the study of the vibrating characteristic of cylindrical resonators. For the vibratory cylinder gyroscope excited by piezo-electric electrodes, mode testing of the cylindrical resonator is difficult. In this paper, a novel vibration testing method for cylindrical resonators is proposed. This method uses a MEMS microphone, which has the characteristics of small size and accurate directivity, to measure the vibration of the cylindrical resonator. A testing system was established, then the system was used to measure the vibration mode of the resonator. The experimental results show that the orientation resolution of the node of the vibration mode is better than 0.1°. This method also has the advantages of low cost and easy operation. It can be used in vibration testing and provide accurate results, which is important for the study of the vibration mode and thermal stability of vibratory cylindrical gyroscopes.

Mobilization and mixing of settled solids in horizontal storage tanks

International Nuclear Information System (INIS)

Cummins, R.L.

1995-01-01

Studies were conducted using submerged jets for the mobilization and mixing of settled solids to form a suspension that can easily be removed from storage tanks. These studies focus on the specific problems relating to horizontal, cylindrical storage tanks. Of primary consideration are the storage tanks located at the Oak Ridge National Laboratory which are used for the collection of remote-handled, radioactive liquid wastes. These wastes are in two phases. A layer of undissolved, settled solids varying from 2 to 4 feet in depth under a layer of supernate. Using a surrogate of the tank contents and an approximate 2/3 dimensional scale tank, tests were performed to determine the optimum design and location of suction and discharge nozzles as well as the minimum discharge velocity required to achieve complete mobilization of the solids in the tank

Weakly nonlinear incompressible Rayleigh-Taylor instability growth at cylindrically convergent interfaces

International Nuclear Information System (INIS)

Wang, L. F.; He, X. T.; Wu, J. F.; Zhang, W. Y.; Ye, W. H.

2013-01-01

A weakly nonlinear (WN) model has been developed for the incompressible Rayleigh-Taylor instability (RTI) in cylindrical geometry. The transition from linear to nonlinear growth is analytically investigated via a third-order solutions for the cylindrical RTI initiated by a single-mode velocity perturbation. The third-order solutions can depict the early stage of the interface asymmetry due to the bubble-spike formation, as well as the saturation of the linear (exponential) growth of the fundamental mode. The WN results in planar RTI [Wang et al., Phys. Plasmas 19, 112706 (2012)] are recovered in the limit of high-mode number perturbations. The difference between the WN growth of the RTI in cylindrical geometry and in planar geometry is discussed. It is found that the interface of the inward (outward) development spike/bubble is extruded (stretched) by the additional inertial force in cylindrical geometry compared with that in planar geometry. For interfaces with small density ratios, the inward growth bubble can grow fast than the outward growth spike in cylindrical RTI. Moreover, a reduced formula is proposed to describe the WN growth of the RTI in cylindrical geometry with an acceptable precision, especially for small-amplitude perturbations. Using the reduced formula, the nonlinear saturation amplitude of the fundamental mode and the phases of the Fourier harmonics are studied. Thus, it should be included in applications where converging geometry effects play an important role, such as the supernova explosions and inertial confinement fusion implosions.

Gravitational Instability of Cylindrical Viscoelastic Medium ...

Indian Academy of Sciences (India)

similar to that of viscoelastic fluid where both properties work together. They also ... cylindrical gravitational waves provides a strong motivation in this regard. .... which represents the solenoidal character of the magnetic field and the total stress.

Determination of colloidal and dissolved silver in water samples using colorimetric solid-phase extraction.

Science.gov (United States)

Hill, April A; Lipert, Robert J; Porter, Marc D

2010-03-15

The increase in bacterial resistance to antibiotics has led to resurgence in the use of silver as a biocidal agent in applications ranging from washing machine additives to the drinking water treatment system on the International Space Station (ISS). However, growing concerns about the possible toxicity of colloidal silver to bacteria, aquatic organisms and humans have led to recently issued regulations by the US EPA and FDA regarding the usage of silver. As part of an ongoing project, we have developed a rapid, simple method for determining total silver, both ionic (silver(I)) and colloidal, in 0.1-1mg/L aqueous samples, which spans the ISS potable water target of 0.3-0.5mg/L (total silver) and meets the US EPA limit of 0.1mg/L in drinking water. The method is based on colorimetric solid-phase extraction (C-SPE) and involves the extraction of silver(I) from water samples by passage through a solid-phase membrane impregnated with the colorimetric reagent DMABR (5-[4-(dimethylamino)benzylidene]rhodanine). Silver(I) exhaustively reacts with impregnated DMABR to form a colored compound, which is quantified using a handheld diffuse reflectance spectrophotometer. Total silver is determined by first passing the sample through a cartridge containing Oxone, which exhaustively oxidizes colloidal silver to dissolved silver(I). The method, which takes less than 2 min to complete and requires only approximately 1 mL of sample, has been validated through a series of tests, including a comparison with the ICP-MS analysis of a water sample from ISS that contained both silver(I) and colloidal silver. Potential earth-bound applications are also briefly discussed. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Two-phase air-solid stationary turbulent flow in a cylindrical tube, with a high massive concentration

International Nuclear Information System (INIS)

Fortier, Andre; Chen, Che Pen

1976-01-01

The momentum theorem, applied separately to the two phases (fluid and solid particles), together with the equations of continuity, gives two differential equations by which the pressure and the concentration along the longitudinal profile x can be computed. These equations can be obtained by introduction of several averaging procedures of physical significance. These quantities are defined in a simple manner for the general case. Using experimental measurements of solid particle velocities in a horizontal tube by radio-tracers, it is shown how to determine the three average coefficients: Λsub(g) friction coefficient of gas, Λsub(s) momentum loss coefficient of solid particles by impacts, against the wall, and Csub(D) drag coefficient due to the velocity difference between the two phases. This determination is based on the numerical solution of the two differential equations conveniently simplified [fr

Observation of unusual irreversible/reversible effects in a macroscopic cylindrical hole drilled in superconducting Bi-Sr-Ca-Cu-O

Energy Technology Data Exchange (ETDEWEB)

Yetis, H. [Department of Physics, Turgut Gulez Research Laboratory, Abant Izzet Baysal University, 14280 Bolu (Turkey)], E-mail: yetis_h@ibu.edu.tr; Kilic, A.; Kilic, K.; Altinkok, A.; Olutas, M. [Department of Physics, Turgut Gulez Research Laboratory, Abant Izzet Baysal University, 14280 Bolu (Turkey)

2008-09-15

Current-voltage (I-V) measurements were carried out for different current sweep rates (dI/dt) of transport current at zero magnetic field (H = 0) and H {ne} 0 in a polycrystalline sample of Bi{sub 1.7}Pb{sub 0.3}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} (BSCCO) with a macroscopic cylindrical hole (CH) drilled. Similar measurements were also performed in the same BSCCO sample without CH for a comparison before drilling CH. For the same values of H, T, and dI/dt taken for both samples, it was observed that hysteresis effects appear in I-V curves upon cycling of transport current in upward and downward directions which contain the increasing and decreasing current values, respectively. However these effects which are seen in I-V curves of BSCCO sample with CH is more prominent than that of the BSCCO sample without CH. Further, the irreversibility effects in I-V curves of the BSCCO sample without CH disappears for H {ne} 0 exhibiting nearly a linear behaviour, whereas the hysteretic behaviour in I-V curves of the BSCCO sample with CH is still observed. This interesting behaviour could be evaluated that macroscopic cylindrical hole improves pinning properties of sample acting as a macroscopic flux pinning center for flux lines.

Confined and interface phonons in combined cylindrical nanoheterosystem

Directory of Open Access Journals (Sweden)

O.M.Makhanets

2006-01-01

Full Text Available The spectra of all types of phonons existing in a complicated combined nanoheterosystem consisting of three cylindrical quantum dots embedded into the cylindrical quantum wire placed into vacuum are studied within the dielectric continuum model. It is shown that there are confined optical (LO and interface phonons of two types: top surface optical (TSO and side surface optical (SSO modes of vibration in such a nanosystem. The dependences of phonon energies on the quasiwave numbers and geometrical parameters of quantum dots are investigated and analysed.

The cylindrical GEM detector of the KLOE-2 experiment

International Nuclear Information System (INIS)

Bencivenni, G.; Ciambrone, P.; De Lucia, E.; Domenici, D.; Felici, G.; Fermani, P.; Morello, G.; Branchini, P.; Cicco, A. Di; Czerwinski, E.

2017-01-01

The KLOE-2 experiment started its data taking campaign in November 2014 with an upgraded tracking system at the DAΦNE electron-positron collider at the Frascati National Laboratory of INFN. The new tracking device, the Inner Tracker, operated together with the KLOE-2 Drift Chamber, has been installed to improve track and vertex reconstruction capabilities of the experimental apparatus. The Inner Tracker is a cylindrical GEM detector composed of four cylindrical triple-GEM detectors, each provided with an X-V strips-pads stereo readout. Although GEM detectors are already used in high energy physics experiments, this device is considered a frontier detector due to its fully-cylindrical geometry: KLOE-2 is the first experiment benefiting of this novel detector technology. Alignment and calibration of this detector will be presented together with its operating performance and reconstruction capabilities.

Cylindrical-confinement-induced phase behaviours of diblock copolymer melts

International Nuclear Information System (INIS)

Mei-Jiao, Liu; Shi-Ben, Li; Lin-Xi, Zhang; Xiang-Hong, Wang

2010-01-01

The phase behaviours of diblock copolymers under cylindrical confinement are studied in two-dimensional space by using the self-consistent field theory. Several phase parameters are adjusted to investigate the cylindrical-confinement-induced phase behaviours of diblock copolymers. A series of lamella-cylinder mixture phases, such as the mixture of broken-lamellae and cylinders and the mixture of square-lamellae and cylinders, are observed by varying the phase parameters, in which the behaviours of these mixture phases are discussed in the corresponding phase diagrams. Furthermore, the free energies of these mixture phases are investigated to illustrate their evolution processes. Our results are compared with the available observations from the experiments and simulations respectively, and they are in good agreement and provide an insight into the phase behaviours under cylindrical confinement. (cross-disciplinary physics and related areas of science and technology)

Buckling localization in a cylindrical panel under axial compression

DEFF Research Database (Denmark)

Tvergaard, Viggo; Needleman, A.

2000-01-01

Localization of an initially periodic buckling pattern is investigated for an axially compressed elastic-plastic cylindrical panel of the type occurring between axial stiffeners on cylindrical shells. The phenomenon of buckling localization and its analogy with plastic flow localization in tensile...... test specimens is discussed in general. For the cylindrical panel, it is shown that buckling localization develops shortly after a maximum load has been attained, and this occurs for a purely elastic panel as well as for elastic-plastic panels. In a case where localization occurs after a load maximum......, but where subsequently the load starts to increase again, it is found that near the local load minimum, the buckling pattern switches back to a periodic type of pattern. The inelastic material behavior of the panel is described in terms of J(2) corner theory, which avoids the sometimes unrealistically high...

Determination of trace impurities in titanium dioxide by direct solid sampling electrothermal atomic absorption spectrometry

Czech Academy of Sciences Publication Activity Database

Vojtková, Blanka; Dočekal, Bohumil

2005-01-01

Roč. 99, S (2005), s489-s491 ISSN 0009-2770. [Meeting on Chemistry and Life /3./. Brno, 20.09.2005-22.09.2005] Institutional research plan: CEZ:AV0Z40310501 Keywords : solid sampling * electrothermal atomic absorption spectrometry * trace analysis Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.445, year: 2005

Optics Demonstrations Using Cylindrical Lenses

Science.gov (United States)

Ivanov, Dragia; Nikolov, Stefan

2015-01-01

In this paper we consider the main properties of cylindrical lenses and propose several demonstrational experiments that can be performed with them. Specifically we use simple glasses full of water to demonstrate some basic geometrical optics principles and phenomena. We also present some less standard experiments that can be performed with such…

Evaluation of the readsorption of plutonium and americium in dynamic fractionations of environmental solid samples

DEFF Research Database (Denmark)

Petersen, Roongrat; Hou, Xiaolin; Hansen, Elo Harald

2008-01-01

A dynamic extraction system exploiting sequential injection (SI) for sequential extractions incorporating a specially designed extraction column is developed to fractionate radionuclides in environmental solid samples such as soils and sediments. The extraction column can contain a large amount...... of soil sample (up to 5 g), and under optimal operational conditions it does not give rise to creation of back pressure. Attention has been placed on studies of the readsorption problems during sequential extraction using a modified Standards, Measurements and Testing (SM&T) scheme with 4-step sequential...

A general solution in the cylindrical coordinates system for the diffusion of a radionuclide in homogeneous and isotropic solids

CERN Document Server

Ribeiro, F B

1999-01-01

Solutions of the diffusion equation in cylindrical coordinates are presented for a radionuclide produced by the decay of a not diffusing parent isotope with arbitrary activity distribution. General initial and Dirichlet boundary conditions are considered and the diffusion equation is solved for a finite cylinder. Solutions corresponding to two particular boundary conditions that can be imposed in laboratory diffusion coefficient measurements are presented. An analysis of the speed of convergence and of the series truncation error is done for these particular solutions. An example of the escape to production ratio derived from one of the solutions is also presented.

A general solution in the cylindrical coordinates system for the diffusion of a radionuclide in homogeneous and isotropic solids

International Nuclear Information System (INIS)

Ribeiro, Fernando Brenha

1999-01-01

Solutions of the diffusion equation in cylindrical coordinates are presented for a radionuclide produced by the decay of a not diffusing parent isotope with arbitrary activity distribution. General initial and Dirichlet boundary conditions are considered and the diffusion equation is solved for a finite cylinder. Solutions corresponding to two particular boundary conditions that can be imposed in laboratory diffusion coefficient measurements are presented. An analysis of the speed of convergence and of the series truncation error is done for these particular solutions. An example of the escape to production ratio derived from one of the solutions is also presented

Characteristic Determination Of Self Shielding Factor And Cadmium Ratio Of Cylindrical Probe

International Nuclear Information System (INIS)

Hamzah, Amir; Budi R, Ita; Pinem, Suriam

1996-01-01

Determination of thermal, epithermal and total self shielding factor and cadmium ratio of cylindrical probe has been done by measurement and calculation. Self shielding factor can be determined by dividing probe activity to Al-alloy probe activity. Due to the lack of cylindrical probe made of Al-alloy, self shielding factor can be determined by parabolic extrapolation of measured activities to 0 cm radius to divide those activities. Theoretically, self shielding factor can be determined by making numerical solution of two dimensional integral equations using Romberg method. To simplify, the calculation is based on single collision theory with the assumption of monoenergetic neutron and isotropic distribution. For gold cylindrical probe, the calculation results are quite close to the measurement one with the relative discrepancy for activities, cadmium ratio and self shielding factor of bare probe are less then 11.5%, 3,5% and 1.5% respectively. The program can be used for the calculation of other kinds of cylindrical probes. Due to dependency to radius, cylindrical probe made of copper has the best characteristic of self shielding factor and cadmium ratio

Thermal transport contributed by the torsional phonons in cylindrical nanowires: Role of evanescent modes

International Nuclear Information System (INIS)

Xie, Zhong-Xiang; Zhang, Yong; Zhang, Li-Fu; Fan, Dian-Yuan

2017-01-01

Thermal transport contributed by the torsional phonons in cylindrical nanowires is investigated by using the isotropic elastic continuum theory. The numerical calculations for both the concavity-shaped and convexity-shaped cylindrical structures are made to reveal the role of the evanescent modes. Results show that the evanescent modes play an important role in influencing the thermal transport in such structures. For the concavity-shaped cylindrical nanowire, the evanescent modes can enhance the thermal conductance by about 20 percent, while for the convexity-shaped cylindrical nanowire, the evanescent modes can suppress the thermal conductance by 6 percent. It is also shown that the influence of the evanescent modes on the thermal conductance is strongly related to the attenuation length of the evanescent modes. A brief analysis of these results is given. - Highlights: • The evanescent modes play an important role in influencing thermal transport contributed by torsional phonons in cylindrical nanowires. • For the concavity-shaped cylindrical nanowire, the evanescent modes can enhance the thermal conductance by about 20 percent, while for the convexity-shaped cylindrical nanowire, they can suppress the thermal conductance by 6 percent.

Thermal transport contributed by the torsional phonons in cylindrical nanowires: Role of evanescent modes

Energy Technology Data Exchange (ETDEWEB)

Xie, Zhong-Xiang [SZU-NUS Collaborative Innovation Center for Optoelectronic Science Technology, International Collaborative Laboratory of 2D Materials for Optoelectronic Science & Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002 (China); Zhang, Yong [Department of Mathematics and Physics, Hunan Institute of Technology, Hengyang 421002 (China); Zhang, Li-Fu, E-mail: zhanglifu68@hotmail.com [SZU-NUS Collaborative Innovation Center for Optoelectronic Science Technology, International Collaborative Laboratory of 2D Materials for Optoelectronic Science & Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); Fan, Dian-Yuan [SZU-NUS Collaborative Innovation Center for Optoelectronic Science Technology, International Collaborative Laboratory of 2D Materials for Optoelectronic Science & Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China)

2017-05-03

Thermal transport contributed by the torsional phonons in cylindrical nanowires is investigated by using the isotropic elastic continuum theory. The numerical calculations for both the concavity-shaped and convexity-shaped cylindrical structures are made to reveal the role of the evanescent modes. Results show that the evanescent modes play an important role in influencing the thermal transport in such structures. For the concavity-shaped cylindrical nanowire, the evanescent modes can enhance the thermal conductance by about 20 percent, while for the convexity-shaped cylindrical nanowire, the evanescent modes can suppress the thermal conductance by 6 percent. It is also shown that the influence of the evanescent modes on the thermal conductance is strongly related to the attenuation length of the evanescent modes. A brief analysis of these results is given. - Highlights: • The evanescent modes play an important role in influencing thermal transport contributed by torsional phonons in cylindrical nanowires. • For the concavity-shaped cylindrical nanowire, the evanescent modes can enhance the thermal conductance by about 20 percent, while for the convexity-shaped cylindrical nanowire, they can suppress the thermal conductance by 6 percent.

Enhancement of exciton radiative recombination for In-doped ZnO nanowires with aluminum cylindrical micropillars

Energy Technology Data Exchange (ETDEWEB)

Wang, Jen-Cheng; Liang, Yu-Ting; Cheng, Fang-Ching; Fang, Chia-Hui; Chen, Hung-Ing; Tsai, Chung-Yuan [Graduate Institute of Electro-Optical Engineering and Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan, ROC (China); Jiang, Joe-Air [Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China); Nee, Tzer-En, E-mail: neete@mail.cgu.edu.tw [Graduate Institute of Electro-Optical Engineering and Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan, ROC (China)

2013-04-15

Zinc oxide (ZnO) has attracted intensive research effort in recent years, due to its unique properties and versatile applications. Recent work on the conservation of surface plasmon (SP) and light through period metal arrays has elucidated the propagation of SP resonance behavior. In this paper, we discuss the enhancement of exciton radiative recombination of the ZnO nanowires with Al cylindrical micropillars. Optical characterization of exciton interacted with SP resonance for indium-doped ZnO nanowires with Al cylindrical micropillars has been also investigated. From photoluminescence spectra of In-doped ZnO nanowires, it is found that the In-doped ZnO nanowires have a blue emission at 425 nm, which resulted from the ZnO band-to-band transition. Prior to the arrays of samples were annealed, a broad green emission centered at 500 nm was observed, which is attributed to ZnO native point defects. The relatively strong green band emission results from the radiative recombination that arises from the ionized oxygen vacancy and surface-defect related luminescence. Compare the In-doped ZnO on Si substrate, the enhancement of PL intensity for In-doped ZnO with deposited Al pattern film can be attributed to strong interaction with SP resonance and exciton over a broad temperature range. These experimental results indicate that Al cylindrical micropillars can significantly enhance carrier confinement and increase the quantum efficiency of In-doped ZnO/Al heterostructures due to the interaction of SP resonance between the In-doped ZnO nanowires and Al cylindrical micropillar structures, the surface-defect related luminescence, and the auxiliary test structures with variable micropillar parameters. -- Highlights: ► We examine the exciton radiative recombination of the ZnO nanowires. ► Al cylindrical micropillars affect the carrier recombination of ZnO/Al structures. ► The interaction of SP resonance between In-doped ZnO nanowire and Al pattern film. ► The carrier

Experimental and numerical investigation of laser forming of cylindrical surfaces with arbitrary radius of curvature

Directory of Open Access Journals (Sweden)

Mehdi Safari

2016-09-01

Full Text Available In this work, laser forming of cylindrical surfaces with arbitrary radius of curvature is investigated experimentally and numerically. For laser forming of cylindrical surfaces with arbitrary radius of curvature, a new and comprehensive method is proposed in this paper. This method contains simple linear irradiating lines and using an analytical method, required process parameters for laser forming of a cylindrical surface with a specific radius of curvature is proposed. In this method, laser output power, laser scanning speed and laser beam diameter are selected based on laser machine and process limitations. As in the laser forming of a cylindrical surface, parallel irradiating lines are needed; therefore key parameter for production of a cylindrical surface with a specific radius of curvature is the number of irradiating lines. Hence, in the proposed analytical method, the required number of irradiating lines for production of a cylindrical surface with a specific radius of curvature is suggested. Performance of the proposed method for production of cylindrical surface with a specific radius of curvature is verified with experimental tests. The results show that using proposed analytical method, cylindrical surfaces with any radius of curvature can be produced successfully.

Mercury speciation in environmental solid samples using thermal release technique with atomic absorption detection

Energy Technology Data Exchange (ETDEWEB)

Shuvaeva, Olga V. [Institute of Inorganic Chemistry, Academician Lavrent' ev Prospect 3, 630090 Novosbirsk (Russian Federation)], E-mail: olga@che.nsk.su; Gustaytis, Maria A.; Anoshin, Gennadii N. [Institute of Geology and Mineralogy, Siberian Branch of Russian Academy of Sciences, Koptyug Prospect 3, 630090 Novosibirsk (Russian Federation)

2008-07-28

A sensitive and very simple method for determination of mercury species in solid samples has been developed involving thermal release analysis in combination with atomic absorption (AAS) detection. The method allows determination of mercury(II) chloride, methylmercury and mercury sulfide at the level of 0.70, 0.35 and 0.20 ng with a reproducibility of the results of 14, 25 and 18%, respectively. The accuracy of the developed assay has been estimated using certified reference materials and by comparison of the results with those of an independent method. The method has been applied for Hg species determination in original samples of lake sediments and plankton.

Optical CT imaging of solid radiochromic dosimeters in mismatched refractive index solutions using a scanning laser and large area detector.

Science.gov (United States)

Dekker, Kurtis H; Battista, Jerry J; Jordan, Kevin J

2016-08-01

The practical use of the PRESAGE® solid plastic dosimeter is limited by the inconvenience of immersing it in high-viscosity oils to achieve refractive index matching for optical computed tomography (CT) scanning. The oils are slow to mix and difficult to clean from surfaces, and the dosimeter rotation can generate dynamic Schlieren inhomogeneity patterns in the reference liquid, limiting the rotational and overall scan speed. Therefore, it would be beneficial if lower-viscosity, water-based solutions with slightly unmatched refractive index could be used instead. The purpose of this work is to demonstrate the feasibility of allowing mismatched conditions when using a scanning laser system with a large acceptance angle detector. A fiducial-based ray path measurement technique is combined with an iterative CT reconstruction algorithm to reconstruct images. A water based surrounding liquid with a low viscosity was selected for imaging PRESAGE® solid dosimeters. Liquid selection was optimized to achieve as high a refractive index as possible while avoiding rotation-induced Schlieren effects. This led to a refractive index mismatch of 6% between liquid and dosimeters. Optical CT scans were performed with a fan-beam scanning-laser optical CT system with a large area detector to capture most of the refracted rays. A fiducial marker placed on the wall of a cylindrical sample occludes a given light ray twice. With knowledge of the rotation angle and the radius of the cylindrical object, the actual internal path of each ray through the dosimeter can be calculated. Scans were performed with 1024 projections of 512 data samples each, and rays were rebinned to form 512 parallel-beam projections. Reconstructions were performed on a 512 × 512 grid using 100 iterations of the SIRT iterative CT algorithm. Proof of concept was demonstrated with a uniformly attenuating solution phantom. PRESAGE® dosimeters (11 cm diameter) were irradiated with Cobalt-60 irradiator to achieve

Optical CT imaging of solid radiochromic dosimeters in mismatched refractive index solutions using a scanning laser and large area detector

Energy Technology Data Exchange (ETDEWEB)

Dekker, Kurtis H., E-mail: kdekker2@uwo.ca [Department of Medical Biophysics, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario N6A 5C1 (Canada); Battista, Jerry J.; Jordan, Kevin J. [Departments of Medical Biophysics and Oncology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario N6A 5C1, Canada and Department of Physics and Engineering, London Regional Cancer Program, London Health Sciences Centre, 790 Commissioners Road East, London, Ontario N6A 4L6 (Canada)

2016-08-15

Purpose: The practical use of the PRESAGE® solid plastic dosimeter is limited by the inconvenience of immersing it in high-viscosity oils to achieve refractive index matching for optical computed tomography (CT) scanning. The oils are slow to mix and difficult to clean from surfaces, and the dosimeter rotation can generate dynamic Schlieren inhomogeneity patterns in the reference liquid, limiting the rotational and overall scan speed. Therefore, it would be beneficial if lower-viscosity, water-based solutions with slightly unmatched refractive index could be used instead. The purpose of this work is to demonstrate the feasibility of allowing mismatched conditions when using a scanning laser system with a large acceptance angle detector. A fiducial-based ray path measurement technique is combined with an iterative CT reconstruction algorithm to reconstruct images. Methods: A water based surrounding liquid with a low viscosity was selected for imaging PRESAGE® solid dosimeters. Liquid selection was optimized to achieve as high a refractive index as possible while avoiding rotation-induced Schlieren effects. This led to a refractive index mismatch of 6% between liquid and dosimeters. Optical CT scans were performed with a fan-beam scanning-laser optical CT system with a large area detector to capture most of the refracted rays. A fiducial marker placed on the wall of a cylindrical sample occludes a given light ray twice. With knowledge of the rotation angle and the radius of the cylindrical object, the actual internal path of each ray through the dosimeter can be calculated. Scans were performed with 1024 projections of 512 data samples each, and rays were rebinned to form 512 parallel-beam projections. Reconstructions were performed on a 512 × 512 grid using 100 iterations of the SIRT iterative CT algorithm. Proof of concept was demonstrated with a uniformly attenuating solution phantom. PRESAGE® dosimeters (11 cm diameter) were irradiated with Cobalt-60

Determination of the shear impedance of viscoelastic liquids using cylindrical piezoceramic resonators.

Science.gov (United States)

Kiełczyński, Piotr; Pajewski, Wincenty; Szalewski, Marek

2003-03-01

In this paper, a new method for determining the rheological parameters of viscoelastic liquids is presented. To this end, we used the perturbation method applied to shear vibrations of cylindrical piezoceramic resonators. The resonator was viscoelastically loaded on the outer cylindrical surface. Due to this loading, the resonant frequency and quality factor of the resonator changed. According to the perturbation method, the change in the complex resonant frequency deltaomega = deltaomega(re) + jdeltaomega(im) is directly proportional to the specific acoustic impedance for cylindrical waves Zc of a viscoelastic liquid surrounding the resonator, i.e., deltaomega is approximately equal to jZc, where j = (-1)1/2. Hence, the measurement of the real and imaginary parts of the complex resonant frequency deltaomega determines the real part, Rc, and imaginary part, Xc, of the complex acoustic impedance for cylindrical waves Zc of an investigated liquid. Furthermore, the specific impedance ZL for plane waves was related to the specific impedance Zc for cylindrical waves. Using theoretical formulas established and the results of the experiments performed, the shear storage modulus mu and the viscosity eta for various liquids (e.g., epoxy resins) were determined. Moreover, the authors derived for cylindrical resonators a formula that relates the shift in resonant frequency to the viscosity of the liquid. This formula is analogous to the Kanazawa-Gordon formula that was derived for planar resonators and Newtonian liquids.

Direct numerical simulations of a thin liquid film coating an axially oscillating cylindrical surface

Energy Technology Data Exchange (ETDEWEB)

Binz, Matthias; Rohlfs, Wilko; Kneer, Reinhold, E-mail: rohlfs@wsa.rwth-aachen.de [Institute of Heat and Mass Transfer, RWTH Aachen University, Augustinerbach 6, D-52056 Aachen (Germany)

2014-08-01

Liquid films on cylindrical bodies like wires or fibers disintegrate into droplets if their length exceeds a critical measure (Plateau–Rayleigh instability). Stabilization of such films can be achieved by an axial oscillation of the solid core provided that a suitable combination of forcing amplitude and frequency is given. To investigate the stabilizing effect, direct numerical simulations of the axisymmetric problem are conducted in this study. Thus, a modified volume-of-fluid solver is employed based on the open source library OpenFOAM{sup ®}. The effect of film stabilization is demonstrated and the required conditions for a stable film configuration are found to be in accordance with other studies. Finally, parameter variations are conducted to investigate the influence on the long-term shape of the stabilized film surface. (paper)

Automated sample preparation station for studying self-diffusion in porous solids with NMR spectroscopy

Science.gov (United States)

Hedin, Niklas; DeMartin, Gregory J.; Reyes, Sebastián C.

2006-03-01

In studies of gas diffusion in porous solids with nuclear magnetic resonance (NMR) spectroscopy the sample preparation procedure becomes very important. An apparatus is presented here that pretreats the sample ex situ and accurately sets the desired pressure and temperature within the NMR tube prior to its introduction in the spectrometer. The gas manifold that supplies the NMR tube is also connected to a microbalance containing another portion of the same sample, which is kept at the same temperature as the sample in the NMR tube. This arrangement permits the simultaneous measurement of the adsorption loading on the sample, which is required for the interpretation of the NMR diffusion experiments. Furthermore, to ensure a good seal of the NMR tube, a hybrid valve design composed of titanium, a Teflon® seat, and Kalrez® O-rings is utilized. A computer controlled algorithm ensures the accuracy and reproducibility of all the procedures, enabling the NMR diffusion experiments to be performed at well controlled conditions of pressure, temperature, and amount of gas adsorbed on the porous sample.

Dynamic plastic buckling of cylindrical and spherical shells

International Nuclear Information System (INIS)

Jones, N.; Okawa, D.M.

1975-01-01

A theoretical analysis is developed to predict the dynamic plastic buckling of a long, impulsively loaded cylindrical shell in order to examine various features of plastic buckling and to assess the importance of several approximations with previous authors have introduced in dynamic plastic buckling studies. The influence of a time-dependent circumferential membrane force, the sharpness of the peaks in the displacement and velocity amplification functions, the restrictions which are implicit when employing the Prandtl-Reuss equations in this class of problems, and the limitations due to elastic unloading are examined in some detail. A summary of all previously published theoretical investigations known to the authors is undertaken for the dynamic plastic behavior of cylindrical shells and rings which are made from rigid-plastic, rigid-visco-plastic, elastic-plastic and elastic-visco-plastic materials and subjected to initial axisymmetric impulsive velocity fields. The theoretical predictions of the dominant motions, critical mode numbers, and threshold impulses are compared and critically reviewed. An experimental investigation was also undertaken into the dynamic plastic buckling of circular rings subjected to uniformly distributed external impulsive velocities. It appears that no experiments have been reported previously on mild steel cylindrical shells with an axial length (L) less than four times the shell radius (R). The experimental values of the average final radial deflections, critical mode numbers and dimensions of the permanent wrinkles in the mild steel and some aliminium 6,061 T6 specimens are compared with all the previously published theoretical predictions and experimental results on cylindrical shells with various axial lengths. (orig./HP) [de

Effect of free swirl flow on the rate of mass and heat transfer at the bottom of a vertical cylindrical container and possible applications

International Nuclear Information System (INIS)

Konsowa, A.H.; Abdel-Aziz, M.H.; Abdo, M.S.E.; Hassan, M.S.; Sedahmed, G.H.

2017-01-01

Highlights: • Mass transfer at the bottom of a cylindrical container was studied under decaying swirl flow. • Parameters studied are swirl flow velocity, diameter of the inlet nozzle and solution properties. • A dimensionless equation was obtained using the significant parameters. • The present results were compared with the results obtained using perpendicular inlet nozzle. • Relevance of study to the design of membrane processes was highlighted. - Abstract: Rates of mass transfer at the base of a vertical cylindrical container were determined under decaying swirl flow by the electrochemical technique. Variables studied were swirl flow solution velocity, diameter of the tangential inlet nozzle and physical properties of the solution. The data were correlated by a dimensionless mass transfer equation. The equation can be used to predict the rate of heat loss from the bottom of swirl flow equipment as well as the rate of diffusion controlled corrosion of the bottom. The importance of the derived equation in the design and scale up of a cylindrical batch recirculating catalytic or electrochemical reactor with a catalyst layer or electrode at the bottom and a cooling jacket around the vertical wall suitable for conducting exothermic liquid – solid diffusion controlled reactions which need rapid temperature control to avoid the loss of heat sensitive catalysts or heat sensitive products was pointed out. Comparison of the present results with the results obtained using perpendicular inlet nozzle which generates parallel flow at the bottom and axial flow along the cylindrical container revealed the fact that although swirl flow produces higher rates of heat and mass transfer at the cylindrical wall than axial flow and the reverse is true at the container base. Relevance of the present study to the design and operation of membrane processes and heat recovery from hot pools of liquid metals and low melting alloys in the production stage was highlighted.

Development of a portable mass spectrometric system for determination of isotopic composition of solid uranium samples using fluorine volatilization. Final report

International Nuclear Information System (INIS)

Loge, G.

1994-01-01

Using hardware and materials supplied by LANL, a prototype quadrupole mass spectrometer system designed for portable field analysis of isotopic composition of solid uranium samples was assembled and tested. The system contained the capability for fluorine volatilization of solid uranium samples with gas introduction, which was successfully tested and demonstrated using 100 mg samples of U 3 O 8 . Determination of precision and accuracy for measuring isotopic composition was performed using isotopic standards. Use with soil samples containing uranium were also attempted. Silicates in the soil forming SiF 4 were found to be a kinetic bottleneck to the formation of UF 6 . This could be avoided by performing some sort of chemical separation as a pre-treatment step, which was demonstrated using nitric acid

Detection of fission fragments using thick samples in contact with solid state nuclear track detectors

International Nuclear Information System (INIS)

Lima, D.A. de; Martins, J.B.; Tavares, O.A.P.

1987-01-01

Whenever use is made of thick samples in contact with solid state nuclear track detectors for determining fission yields, one of the fundamental problems is the evaluation of the effective number of target nuclei which contributes to the fraction of the number of fission events that will be recorded. The evaluation of the effective number of target nuclei which contributes to recorded events is based on the effective thickness of the sample. A method for evaluating effective thickness of thick samples for binary fission modes, is presented. A cross section equation which takes into account all the necessary corrections due to fragment attenuation effects by a thick target for calculation induced fission yields, was obtained. (Author) [pt

Reflight of the Solid Surface Combustion Experiment: Opposed-Flow Flame Spread Over Cylindrical Fuels

Science.gov (United States)

Bhattacharjee, Subrata; Altenkirch, Robert A.; Worley, Regis; Tang, Lin; Bundy, Matt; Sacksteder, Kurt; Delichatsios, Michael A.

1997-01-01

The effort described here is a reflight of the Solid Surface Combustion Experiment (SSCE), with extension of the flight matrix first and then experiment modification. The objectives of the reflight are to extend the understanding of the interplay of the radiative processes that affect the flame spread mechanisms.

Reimiep 87. An interlaboratory U-235 enrichment determination by gamma measurement on solid UF6 sample

International Nuclear Information System (INIS)

Aparo, M.; Cresti, P.

1988-01-01

Gamma spectroscopy technique, based on the measurement of U 235 186 KeV flux, is now currently used for the determination of Uranium enrichment in different material of nuclear fuel cycle, namely: Uranium metallic, UO 2 pellets, UF 6 liquid or solid. The present paper describes the use of such a technique and the obtained results in determining the U 235 /U atomic isotopic abundance on a certified UF 6 solid sample. The measurements have been carried out in the frame work of the partecipation to the ''UF 6 Interlaboratory Measurements Evaluation Programme'' organized by CBNM/Geel with the support of the ESARDA (European Safeguards Research and Development Association)

Cylindrically converging blast waves in air

Science.gov (United States)

Matsuo, H.; Nakamura, Y.

1981-07-01

Cylindrically converging shock waves are produced by utilizing the detonation of cylindrical explosive shells. The production and the propagation of shock waves are observed by framing and streak camera photographs, and the trajectory of shock propagations is determined by using an electrical ionization probing system. The effect of the quantity of explosives on the stability, or the axial symmetry, of shock fronts and on the strength of shocks produced is investigated. It has been shown that, for practical purposes, the approximation of shock trajectories by Guderley's formulas would be sufficiently acceptable in an unexpectedly wide region near the implosion center, and that the axial symmetry of the shock front is improved by increasing the quantity of explosives, and thus, strong shocks are produced by merely increasing the quantity of explosives. The reflected diverging shock seems to be very stable. Piezoelectric elements have also been used to detect reflected diverging waves.

The indicating FTA elute cartridge a solid sample carrier to detect high-risk HPV and high-grade cervical lesions

NARCIS (Netherlands)

Bie, R.P. de; Schmeink, C.E.; Bakkers, J.M.J.E.; Snijders, P.J.L.M.; Quint, W.G.V.; Massuger, L.F.A.G.; Bekkers, R.L.M.; Melchers, W.J.G.

2011-01-01

The clinically validated high-risk human papillomavirus (hrHPV) Hybrid Capture 2 (HC2) and GP5+/6+-PCR assays were analyzed on an Indicating FTA Elute cartridge (FTA cartridge). The FTA cartridge is a solid dry carrier that allows safe transport of cervical samples. FTA cartridge samples were

Flux pinning characteristics in cylindrical ingot niobium used in superconducting radio frequency cavity fabrication

OpenAIRE

Dhavale, Asavari S.; Dhakal, Pashupati; Polyanskii, Anatolii A.; Ciovati, Gianluigi

2012-01-01

We present the results of from DC magnetization and penetration depth measurements of cylindrical bulk large-grain (LG) and fine-grain (FG) niobium samples used for the fabrication of superconducting radio frequency (SRF) cavities. The surface treatment consisted of electropolishing and low temperature baking as they are typically applied to SRF cavities. The magnetization data were fitted using a modified critical state model. The critical current density Jc and pinning force Fp are calculat...

Thermal convection in a co-rotating cylindrical annulus

Science.gov (United States)

Kang, Changwoo; Meyer, Antoine; Mutabazi, Innocent

2017-11-01

We investigate thermal convection in a fluid of thermal expansion coefficient α, kinematic viscosity ν, thermal diffusivity κ in a cylindrical annulus of inner radius a and outer radius bwith a solid body rotation of angular frequency Ω and an inward heating with a temperature difference ΔT. The control parameters are η = a/b, Pr = ν / κ and the Rayleigh number Ra = αΔ T gd3 / νκ where the centrifugal gravity gc =Ω2 (a +b)/2. We adopt the generalized Boussinesq approximation. Linear stability analysis shows that for infinite annulus, the threshold Rac decreases with η and tends to the value Rac = 1708 when η -> 1 and that critical modes are columnar vortices. Direct numerical simulations using periodic boundary conditions in the axial direction, show that the columnar vortices appear via a supercritical bifurcation. Higher modes of columnar vortices have been determined using the frequency spectra and the Nusselt number for Pr =1 and η = 0.5 : drifting vortices, vacillation modes and chaotic modes have been identified from Ra =1700 to Ra =107 The contribution of the centrifugal buoyancy to the variation of the kinetic energy in the flow is analysed. This work was supported by the project BIOENGINE (CPER-FEDER, Normandie) and CNES.

Response of Solid and Liquid Targets to High Power Proton Beams for Neutrino Factories

CERN Document Server

Sievers, P

2000-01-01

The response of solid and liquid targets to rapid heating by the incident proton beam is assessed in a classical way, among other things by solving the wave equation under linear conditions and in cylindrical symmetry. This study provides bench mark values and allows to identify critical issues and limiting factors which can help to guide further investigations with more sophisticated means.

Preliminary measurement performance evaluation of a new white light interferometer for cylindrical surfaces

International Nuclear Information System (INIS)

Albertazzi, Armando Jr; Pont, Alex Dal

2005-01-01

This paper introduces a new design of a white light interferometer, suitable for measurement of cylindrical or quasi-cylindrical parts. A high precision 45 deg. conical mirror is used to direct collimated light radially, making it possible to measure in true cylindrical coordinates. The image of the measurand, distorted by the conical mirror, is projected in a high resolution digital camera. A mapping algorithm is used to reconstruct the cylindrical geometry from the distorted image. The rest of the interferometer is quite similar to a conventional white light interferometer: A flat reference mirror is scanned through the measurement range while an algorithm is searching for the maximum contrast position of the interference pattern. The performance evaluation of a configuration suitable for measurement of external cylindrical surfaces is also presented in this paper. A master cylinder was used as reference. Uncertainties of about 1.0 μm were found at the present stage of development

Cylindrical Induction Melter Modicon Control System

International Nuclear Information System (INIS)

Weeks, G.E.

1998-04-01

In the last several years an extensive R ampersand D program has been underway to develop a vitrification system to stabilize Americium (Am) and Curium (Cm) inventories at SRS. This report documents the Modicon control system designed for the 3 inch Cylindrical Induction Melter (CIM)

A strong focussing cylindrical electrostatic quadrupole

International Nuclear Information System (INIS)

Sheng Yaochang

1986-01-01

The construction and performance of small cylindrical electrostatic quadrupole, which is installed in JM-400 pulse electrostatic accelerator, are described. This electrostatic quadrupole is not only used in neutron generator, but also suitable for ion injector as well as for low energy electron accelerator

Application of direct solid sample analysis for the determination of chlorine in biological materials using electrothermal vaporization inductively coupled plasma mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Santos de Gois, Jefferson; Pereira, Éderson R. [Departamento de Química, Universidade Federal de Santa Catarina, 88040-970 Florianópolis, SC (Brazil); Welz, Bernhard [Departamento de Química, Universidade Federal de Santa Catarina, 88040-970 Florianópolis, SC (Brazil); INCT de Energia e Ambiente do CNPq (Brazil); Borges, Daniel L.G., E-mail: daniel.borges@ufsc.br [Departamento de Química, Universidade Federal de Santa Catarina, 88040-970 Florianópolis, SC (Brazil); INCT de Energia e Ambiente do CNPq (Brazil)

2015-03-01

This work describes a methodology developed to carry out Cl determination in biological materials using electrothermal vaporization inductively coupled plasma mass spectrometry and direct solid sample analysis. The solid samples were directly weighed into graphite ‘cups’ and inserted into the graphite furnace. The RF power and the carrier gas flow rate were optimized at 1300 W and 0.7 L min{sup −1}, respectively. Calibration could be carried out using aqueous standard solutions with pre-dried modifiers (Pd + Nd or Pd + Ca) or using solid certified reference materials with the same pre-dried modifiers or without the use of modifiers. The limit of quantification was determined as 5 μg g{sup −1} under optimized conditions and the Cl concentration was determined in five certified reference materials with certified concentrations for Cl, in addition to three certified reference materials, for which certified values for Cl were unavailable; in the latter case, the results were compared with those obtained using high-resolution continuum source molecular absorption spectrometry. Good agreement at a 95% statistical confidence level was achieved between determined and certified or reference values. - Highlights: • Direct determination of chlorine in solid biological materials is described for the first time using ICP-MS. • Calibration against aqueous standards is feasible. • The method is accurate and sensitive, regardless of the composition of the solid sample.

Measurement of angular scattering function and degree of linear polarization of bentonite clay particles embedded in cylindrical epoxy matrix

Directory of Open Access Journals (Sweden)

A. Gogoi

2011-09-01

Full Text Available Scattering properties of bentonite clay particles were investigated at 543.5 nm incident laser wavelength by using a designed and fabricated light scattering setup. The scattering samples were held in front of a laser beam by using a transparent cylindrical thermosetting epoxy matrix.

Comparison of the solid-phase extraction efficiency of a bounded and an included cyclodextrin-silica microporous composite for polycyclic aromatic hydrocarbons determination in water samples.

Science.gov (United States)

Mauri-Aucejo, Adela; Amorós, Pedro; Moragues, Alaina; Guillem, Carmen; Belenguer-Sapiña, Carolina

2016-08-15

Solid-phase extraction is one of the most important techniques for sample purification and concentration. A wide variety of solid phases have been used for sample preparation over time. In this work, the efficiency of a new kind of solid-phase extraction adsorbent, which is a microporous material made from modified cyclodextrin bounded to a silica network, is evaluated through an analytical method which combines solid-phase extraction with high-performance liquid chromatography to determine polycyclic aromatic hydrocarbons in water samples. Several parameters that affected the analytes recovery, such as the amount of solid phase, the nature and volume of the eluent or the sample volume and concentration influence have been evaluated. The experimental results indicate that the material possesses adsorption ability to the tested polycyclic aromatic hydrocarbons. Under the optimum conditions, the quantification limits of the method were in the range of 0.09-2.4μgL(-1) and fine linear correlations between peak height and concentration were found around 1.3-70μgL(-1). The method has good repeatability and reproducibility, with coefficients of variation under 8%. Due to the concentration results, this material may represent an alternative for trace analysis of polycyclic aromatic hydrocarbons in water trough solid-phase extraction. Copyright © 2016 Elsevier B.V. All rights reserved.

The analytic nodal method in cylindrical geometry

International Nuclear Information System (INIS)

Prinsloo, Rian H.; Tomasevic, Djordje I.

2008-01-01

Nodal diffusion methods have been used extensively in nuclear reactor calculations, specifically for their performance advantage, but also for their superior accuracy. More specifically, the Analytic Nodal Method (ANM), utilising the transverse integration principle, has been applied to numerous reactor problems with much success. In this work, a nodal diffusion method is developed for cylindrical geometry. Application of this method to three-dimensional (3D) cylindrical geometry has never been satisfactorily addressed and we propose a solution which entails the use of conformal mapping. A set of 1D-equations with an adjusted, geometrically dependent, inhomogeneous source, is obtained. This work describes the development of the method and associated test code, as well as its application to realistic reactor problems. Numerical results are given for the PBMR-400 MW benchmark problem, as well as for a 'cylindrisized' version of the well-known 3D LWR IAEA benchmark. Results highlight the improved accuracy and performance over finite-difference core solutions and investigate the applicability of nodal methods to 3D PBMR type problems. Results indicate that cylindrical nodal methods definitely have a place within PBMR applications, yielding performance advantage factors of 10 and 20 for 2D and 3D calculations, respectively, and advantage factors of the order of 1000 in the case of the LWR problem

Dynamic Flow-through Methods for Metal Fractionation in Environmental Solid Samples

DEFF Research Database (Denmark)

Miró, Manuel; Hansen, Elo Harald; Petersen, Roongrat

occurring processes always take place under dynamic conditions, recent trends have been focused on the development of alternative flow-through dynamic methods aimed at mimicking environmental events more correctly than their classical extraction counterparts. In this lecture particular emphasis is paid......Accummulation of metal ions in different compartments of the biosphere and their possible mobilization under changing environmental conditions induce a pertubation of the ecosystem and may cause adverse health effects. Nowadays, it is widely recognized that the information on total content...... the ecotoxicological significance of metal ions in solid environmental samples. The background of end-over-end fractionation for releasing metal species bound to particular soil phases is initially discussed, its relevant features and limitations being thoroughly described. However, taking into account that naturally...

Direct determination of chromium in infant formulas employing high-resolution continuum source electrothermal atomic absorption spectrometry and solid sample analysis.

Science.gov (United States)

Silva, Arlene S; Brandao, Geovani C; Matos, Geraldo D; Ferreira, Sergio L C

2015-11-01

The present work proposed an analytical method for the direct determination of chromium in infant formulas employing the high-resolution continuum source electrothermal atomic absorption spectrometry combined with the solid sample analysis (SS-HR-CS ET AAS). Sample masses up to 2.0mg were directly weighted on a solid sampling platform and introduced into the graphite tube. In order to minimize the formation of carbonaceous residues and to improve the contact of the modifier solution with the solid sample, a volume of 10 µL of a solution containing 6% (v/v) H2O2, 20% (v/v) ethanol and 1% (v/v) HNO3 was added. The pyrolysis and atomization temperatures established were 1600 and 2400 °C, respectively, using magnesium as chemical modifier. The calibration technique was evaluated by comparing the slopes of calibration curves established using aqueous and solid standards. This test revealed that chromium can be determined employing the external calibration technique using aqueous standards. Under these conditions, the method developed allows the direct determination of chromium with limit of quantification of 11.5 ng g(-1), precision expressed as relative standard deviation (RSD) in the range of 4.0-17.9% (n=3) and a characteristic mass of 1.2 pg of chromium. The accuracy was confirmed by analysis of a certified reference material of tomato leaves furnished by National Institute of Standards and Technology. The method proposed was applied for the determination of chromium in five different infant formula samples. The chromium content found varied in the range of 33.9-58.1 ng g(-1) (n=3). These samples were also analyzed employing ICP-MS. A statistical test demonstrated that there is no significant difference between the results found by two methods. The chromium concentrations achieved are lower than the maximum limit permissible for chromium in foods by Brazilian Legislation. Copyright © 2015. Published by Elsevier B.V.

Research on cylindrical indexing cam’s unilateral machining

Directory of Open Access Journals (Sweden)

Junhua Chen

2015-08-01

Full Text Available The cylindrical cam ridge of the indexer is a spatial curved surface, which is difficult to design and machine. The cylindrical cam has some defects after machining because conventional machining methods have inaccuracies. This article aims at proposing a precise way to machine an indexing cam, using basic motion analysis and analytic geometry approach. Analytical methodology is first applied in the cam’s motion analysis, to obtain an error-free cam follower’s trajectory formula, and then separate the continuous trajectory curve by thousandth resolution, to create a three-dimensional discrete trajectory curve. Planar formulae and spherical formulae can be built on the loci. Based on the machine principle, the cutting cutter’s position and orientation will be taken into account. This article calculates the formula set as presented previously and obtains the ultimate cutter path coordinate value. The new error-free cutter path trajectory is called the unilateral machining trajectory. The earned results will compile into numerical control processing schedule. This processing methodology gives a convenient and precision way to manufacture a cylindrical indexing cam. Experimental results are also well supported.

EPA Method 3135.2I: Cyanide, Total and Amenable in Aqueous and Solid Samples Automated Colorimetric With Manual Digestion

Science.gov (United States)

This method describes procedures for preparation and analysis of solid, water and wipe samples for detection and measurement of cyanide amendable to chlorination using acid digestion and spectrophotometry.

Wellposedness of a cylindrical shell model

International Nuclear Information System (INIS)

McMillan, C.

1994-01-01

We consider a well-known model of a thin cylindrical shell with dissipative feedback controls on the boundary in the form of forces, shears, and moments. We show that the resulting closed loop feedback problem generates a s.c. semigroup of contractions in the energy space

Flux dynamics and magnetovoltage measurements in a macroscopic cylindrical hole drilled in BSCCO

International Nuclear Information System (INIS)

Yetis, H.; Altinkok, A.; Olutas, M.; Kilic, A.; Kilic, K.

2007-01-01

Slow transport relaxation measurements (V-t curves) and magnetovoltage measurements (V-H curves) were carried out in a polycrystalline sample of Bi 1.7 Pb 0.3 Sr 2 Ca 2 Cu 3 O x (BSCCO) with a macroscopic cylindrically drilled hole (CH). The time evolution of quenched state in V-t curves was interpreted in terms of enhancement of the superconducting order parameter and the relaxation of moving entity. Upon cycling of the external magnetic field with different sweep rates, unusual counter clockwise hysteresis effects and asymmetry in V-H curves are observed in BSCCO sample with CH, which can also be correlated to the trapping of the macroscopic flux bundles in CH

Flux dynamics and magnetovoltage measurements in a macroscopic cylindrical hole drilled in BSCCO

Science.gov (United States)

Yetiş, H.; Altinkok, A.; Olutaş, M.; Kiliç, A.; Kiliç, K.

2007-10-01

Slow transport relaxation measurements (V-t curves) and magnetovoltage measurements (V-H curves) were carried out in a polycrystalline sample of Bi1.7Pb0.3Sr2Ca2Cu3Ox (BSCCO) with a macroscopic cylindrically drilled hole (CH). The time evolution of quenched state in V-t curves was interpreted in terms of enhancement of the superconducting order parameter and the relaxation of moving entity. Upon cycling of the external magnetic field with different sweep rates, unusual counter clockwise hysteresis effects and asymmetry in V-H curves are observed in BSCCO sample with CH, which can also be correlated to the trapping of the macroscopic flux bundles in CH.

Scattering of electromagnetic waves by an non-uniform cylindrical plasma; Diffusion coherente d'une onde electromagnetique par un cylindre de plasma inhomogene

Energy Technology Data Exchange (ETDEWEB)

Faugeras, P E [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires. Groupe de recherches sur la fusion controlee

1967-07-01

The problem of the scattering of plane electromagnetic waves from a non-uniform, cylindrically symmetrical plasma is solved analytically, by a self-consistent field method, for a wave with the electric field parallel to the cylinder axis. Numerical results for the diffracted field are plotted for interesting ranges of the parameters involved: diameter, density on the axis, radial profile of the density, and collision frequencies. The case where the incident field is cylindric (waves surfaces parallel to the cylinder axis) is examined - this permits to connect theoretical calculations and experimental diffraction patterns, and also to explain the diffraction effects observed in a classical microwave interferometry experiment. These results, and the possibility of measuring exactly the diffracted field (showed by experiments with dielectric and metallic rods) lead to a new plasma diagnostic method, based on the diffraction, which has no theoretical limitations and it usable when the classical free-space wave methods are not (plasma diameter lower than 10 wave lengths). The feasibility of this method is tested with a plasma at atmospheric pressure and a 2 mm incident wavelength. The plasma is obtained by the laminar flow of a plasma torch, with a working gas (He or Ar) seeded by potassium (density continuously variable between 10{sup 11} and 10{sup 15} e/cm{sup 3}. Some diffraction patterns by this plasma and for various incident waves, are also given and explained with theoretical calculations. (author) [French] On etudie la diffusion coherente d'une onde electromagnetique par un cylindre de plasma inhomogene par une methode de champ self-consistant, et pour une onde de vecteur electrique parallele a l'axe du cylindre. On a calcule le champ diffracte en faisant varier le diametre du cylindre, la densite sur l'axe, le profil de densite et les frequences de collisions, et on donne ici les principaux resultats. On examine ensuite le cas d'une onde incidente cylindrique

On the dynamics of cylindrical z-pinch

International Nuclear Information System (INIS)

Solov'ev, L.S.

1984-01-01

The stationary configurations of cylindrical plasma flow in the framework of two-liquid relativistic electromagnetic gas dynamics (REMG)) and nonlinear radial oscillations of the plasma cylinder with longitudinal current in the framework of classical monoliquid MGD are considered. It is shown that at sufficiently high conductivity Z-pinch is stable relative to one-dimensional radial perturbations and its motion represents respectively nonlinear radial oscillations. In case of a rather low conductivity or low particle concentration there is in cross section a stability also in relation to the development of sausage type instability. The performed investigations of cylindrical equilibrium and radial oscillations give a qualitative representation on plasma behaviour in Z-pinch at the initial stage of it compression and expansion as well as on motion in an average plane of the developing sausage type instability

A novel three-axis cylindrical hohlraum designed for inertial confinement fusion ignition

Science.gov (United States)

Kuang, Longyu; Li, Hang; Jing, Longfei; Lin, Zhiwei; Zhang, Lu; Li, Liling; Ding, Yongkun; Jiang, Shaoen; Liu, Jie; Zheng, Jian

2016-10-01

A novel ignition hohlraum for indirect-drive inertial confinement fusion is proposed, which is named three-axis cylindrical hohlraum (TACH). TACH is a kind of 6 laser entrance holes (LEHs) hohlraum, which is orthogonally jointed of three cylindrical hohlraums. Laser beams are injected through every entrance hole with the same incident angle of 55°. A view-factor simulation result shows that the time-varying drive asymmetry of TACH is less than 1.0% in the whole drive pulse period without any supplementary technology. Coupling efficiency of TACH is close to that of 6 LEHs spherical hohlraum with corresponding size. Its plasma-filling time is close to that of typical cylindrical ignition hohlraum. Its laser plasma interaction has as low backscattering as the outer cone of the cylindrical ignition hohlraum. Therefore, TACH combines most advantages of various hohlraums and has little predictable risk, providing an important competitive candidate for ignition hohlraum.

Solvent-assisted dispersive solid-phase extraction: A sample preparation method for trace detection of diazinon in urine and environmental water samples.

Science.gov (United States)

Aladaghlo, Zolfaghar; Fakhari, Alireza; Behbahani, Mohammad

2016-09-02

In this research, a sample preparation method termed solvent-assisted dispersive solid-phase extraction (SA-DSPE) was applied. The used sample preparation method was based on the dispersion of the sorbent into the aqueous sample to maximize the interaction surface. In this approach, the dispersion of the sorbent at a very low milligram level was received by inserting a solution of the sorbent and disperser solvent into the aqueous sample. The cloudy solution created from the dispersion of the sorbent in the bulk aqueous sample. After pre-concentration of the diazinon, the cloudy solution was centrifuged and diazinon in the sediment phase dissolved in ethanol and determined by gas chromatography-flame ionization detector. Under the optimized conditions (pH of solution=7.0, Sorbent: benzophenone, 2%, Disperser solvent: ethanol, 500μL, Centrifuge: centrifuged at 4000rpm for 3min), the method detection limit for diazinon was 0.2, 0.3, 0.3 and 0.3μgL(-1) for distilled water, lake water, waste water and urine sample, respectively. Furthermore, the pre-concentration factor was 363.8, 356.1, 360.7 and 353.38 in distilled water, waste water, lake water and urine sample, respectively. SA-DSPE was successfully used for trace monitoring of diazinon in urine, lake and waste water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Self shielding in cylindrical fissile sources in the APNea system

International Nuclear Information System (INIS)

Hensley, D.

1997-01-01

In order for a source of fissile material to be useful as a calibration instrument, it is necessary to know not only how much fissile material is in the source but also what the effective fissile content is. Because uranium and plutonium absorb thermal neutrons so Efficiently, material in the center of a sample is shielded from the external thermal flux by the surface layers of the material. Differential dieaway measurements in the APNea System of five different sets of cylindrical fissile sources show the various self shielding effects that are routinely encountered. A method for calculating the self shielding effect is presented and its predictions are compared with the experimental results

Bulk sample self-attenuation correction by transmission measurement

International Nuclear Information System (INIS)

Parker, J.L.; Reilly, T.D.

1976-01-01

Various methods used in either finding or avoiding the attenuation correction in the passive γ-ray assay of bulk samples are reviewed. Detailed consideration is given to the transmission method, which involves experimental determination of the sample linear attenuation coefficient by measuring the transmission through the sample of a beam of gamma rays from an external source. The method was applied to box- and cylindrically-shaped samples

Cylindrical collapse and gravitational waves

Energy Technology Data Exchange (ETDEWEB)

Herrera, L [Escuela de FIsica, Faculdad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela (Venezuela); Santos, N O [Universite Pierre et Marie Curie, CNRS/FRE 2460 LERMA/ERGA, Tour 22-12, 4eme etage, BoIte 142, 4 place Jussieu, 75252 Paris Cedex 05 (France); Laboratorio Nacional de Computacao Cientifica, 25651-070 Petropolis RJ (Brazil); Centro Brasileiro de Pesquisas Fisicas, 22290-180 Rio de Janeiro RJ (Brazil)

2005-06-21

We study the matching conditions for a collapsing anisotropic cylindrical perfect fluid, and we show that its radial pressure is non-zero on the surface of the cylinder and proportional to the time-dependent part of the field produced by the collapsing fluid. This result resembles the one that arises for the radiation-though non-gravitational-in the spherically symmetric collapsing dissipative fluid, in the diffusion approximation.

Visualization of the flow in a cylindrical container with a rotating disk

Science.gov (United States)

Imahoko, Ryoki; Kurakata, Hiroki; Sakakibara, Jun

2017-11-01

We studied a behavior of the flow in a cylindrical container with a rotating disk. The apparatus consists of a fixed cylindrical container of the inner diameter of 140 mm and height H, and a coaxial rotating disc with a diameter of 140 mm connected with a cylindrical shaft driven by an electrical motor. The radial gap between rotating disk and side wall is very slight distance. The height H is variable up to 100 mm. The velocity distribution in the container was measured by means of particle image velocimetry (PIV). The results of this experiments will be discussed at the conference.

Determination of cobalt in biological samples by line-source and high-resolution continuum source graphite furnace atomic absorption spectrometry using solid sampling or alkaline treatment

International Nuclear Information System (INIS)

Ribeiro, Anderson Schwingel; Vieira, Mariana Antunes; Furtado da Silva, Alessandra; Borges, Daniel L. Gallindo; Welz, Bernhard; Heitmann, Uwe; Curtius, Adilson Jose

2005-01-01

Two procedures for the determination of Co in biological samples by graphite furnace atomic absorption spectrometry (GF AAS) were compared: solid sampling (SS) and alkaline treatment with tetramethylammonium hydroxide (TMAH) using two different instruments for the investigation: a conventional line-source (LS) atomic absorption spectrometer and a prototype high-resolution continuum source atomic absorption spectrometer. For the direct introduction of the solid samples, certified reference materials (CRM) were ground to a particle size ≤50 μm. Alkaline treatment was carried out by placing about 250 mg of the sample in polypropylene flasks, adding 2 mL of 25% m/v tetramethylammonium hydroxide and de-ionized water. Due to its unique capacity of providing a 3-D spectral plot, a high-resolution continuum source (HR-CS) graphite furnace atomic absorption spectrometry was used as a tool to evaluate potential spectral interferences, including background absorption for both sample introduction procedures, revealing that a continuous background preceded the atomic signal for pyrolysis temperatures lower than 700 deg. C. Molecular absorption bands with pronounced rotational fine structure appeared for atomization temperatures >1800 deg. C probably as a consequence of the formation of PO. After optimization had been carried out using high resolution continuum source atomic absorption spectrometry, the optimized conditions were adopted also for line-source atomic absorption spectrometry. Six biological certified reference materials were analyzed, with calibration against aqueous standards, resulting in agreement with the certified values (according to the t-test for a 95% confidence level) and in detection limits as low as 5 ng g -1

Stir-bar supported micro-solid-phase extraction for the determination of polychlorinated biphenyl congeners in serum samples.

Science.gov (United States)

Sajid, Muhammad; Basheer, Chanbasha

2016-07-15

In present work, a new configuration of micro-solid phase extraction was introduced and termed as stir-bar supported micro-solid-phase extraction (SB-μ-SPE). A tiny stir-bar was packed inside the porous polypropylene membrane along with sorbent material and the edges of membrane sheet were heat sealed to secure the contents. The packing of stir-bar inside the μ-SPE device does not allow the device to stick with the wall or any corner of the sample vial during extraction, which is, however, a frequent observation in routine μ-SPE. Moreover, it enhances effective surface area of the sorbent exposed to sample solution through continuous agitation (motion and rotation). It also completely immerses the SB-μ-SPE device in the sample solution even for non-polar sorbents. Polychlorinated biphenyls (PCBs) were selected as model compounds and the method performance was evaluated in human serum samples. After extraction, samples were analyzed by gas chromatography mass spectrometry (GC-MS). The factors that affect extraction efficiency of SB-μ-SPE were optimized. Under optimum conditions, a good linearity (0.1-100ngmL(-1)) with coefficients of determinations ranging from 0.9868 to 0.9992 was obtained. Limits of detections were ranged between 0.003 and 0.047ngmL(-1). Acceptable values for inter-day (3.2-9.1%) and intra-day (3.1-7.2%) relative standard deviations were obtained. The optimized method was successfully applied to determine the concentration of PCB congeners in human serum samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Determination of Sr-90 in environmental samples using solid phase extraction disk

International Nuclear Information System (INIS)

Zal U'yun Wan Mahmood

2002-01-01

A method is described for determination of Sr-90 in environmental samples using solid phase extraction disk (Empore TM Strontium Rad Disk) and GM counter. To determine the optimum condition for capacity of Empore TM Strontium Rad Disk, its characterization studies such as the effects Sr content, acidity (molarity) of acids, presence of Ca 2+ and other major ions (Na + , Mg 2+ etc), influence of interference (Pb and Bi) and others were carried out. An optimized the using of Empore TM Strontium Rad Disk for determination of Sr-90 was validated by application to environmental samples. Quantitative recoveries above 95%for Sr (stable) were recorded in 6M HCl condition. Typical environmental samples may contain an assortment of anionic and cationic species, but in general, Empore TM Strontium Rad Disk has enough capacity to effectively separate Sr for wide variety of aqueous solutions. Sr recovery in a matrix-free or the content of matrix less than 300 mg/sample is typically greater than 99% is reported in this research work. In particular, sample, which may contain interference such as Pb and Bi would require an addition separation step before processing to ensure an accurate measurement of Sr. In this research work, radiotracer 85 Sr was used to monitor the behavior of Sr and calculation its recovery. For analytical methods that can count Y-90, the Sr-90 activity/concentration in environmental sample was calculated. The concentration of Sr-90 in ash sample (Quality Controled Sample) of 276 ± 18 Bq/kg ash was determined from Y-90 activity. The relative percent difference of 1.1% was achievable for Empore TM Sr-Rad Disk methods when compared to the conventional method (fumed-HNO 3 method) - 279 ± 11 Bq/kg ash. (Author)

Dynamic Consolidation and Investigation of Nanostructural W-Cu / W-Y Cylindrical Billets

Science.gov (United States)

Godibadze, B.; Dgebuadze, A.; Chagelishvili, E.; Mamniashvili, G.; Peikrishvili, A.

2018-03-01

The main purpose of presented work is to obtain W-Cu & W-Y cylindrical bulk nanostructured billets by explosive consolidation technology (ECT) in hot condition, with low porosity near to theoretical densities and improved physical / mechanical properties. Nanocomposites were subjected to densification into cylindrical steel tube containers using hot explosive consolidation (HEC) technology to fabricate high dense cylindrical billets. The first stage : Preliminary explosive densification of the precursor powder blend is carried out at room temperature with a loading intensity up to 10GPa to increase the initial density and to activate the particle surfaces in the blend. The second stage investigation were carried out for the same already predensified billets, but consolidation were conducted in hot conditions, after heating of samples in between 940-11000C, the intensity of loading was equal to 10GPa. Consolidated different type of W-Cu composition containing 10-40% of nanoscale W, during investigation showed that the combination of high temperatures (above 940°C) and two-stage shock wave compression was beneficial to the consolidation of the incompatible pair W-Cu composites, resulting in high densities, good integrity and good electronic properties. The structure and property of the samples obtained, depended on the sizes of tungsten particles. It was established that in comparison with W-Cu composites with coarse tungsten the application of nanoscale W precursors and depending of content of W gives different result. Tungsten is a prime material candidate for the first wall of a future fusion reactor. In this study, the microstructure and microhardness of tungsten-yttrium (W-Y) composites were investigated as a function of Y doping content (0.5÷2 wt. %). It was found that the crystallite sizes and the powder particle sizes were increased as a result of the increase of Y content. Nearly fully dense materials were obtained for W-Y alloys when the Y content was

Shear stresses around circular cylindrical openings

NARCIS (Netherlands)

Hoogenboom, P.C.J.; Van Weelden, C.; Blom, C.M.B.

2010-01-01

In this paper stress concentrations are studied around circular cylindrical openings or voids in a linear elastic continuum. The loading is such that a uniform shear stress occurs in the continuum, which is disturbed by the opening. The shear stress is in the direction of the centre axis of the

Anaerobic digestion of solid material

DEFF Research Database (Denmark)

Vavilin, V.A.; Lokshina, L.Y.; Flotats, X.

2007-01-01

A new multidimensional (3 and 2D) anaerobic digestion model for cylindrical reactor with non-uniform influent concentration distributions was developed to study the way in which mixing intensity affects the efficiency of continuous-flow anaerobic digestion. Batch experiments reported and simulated...... earlier by Vavilin and Angelidaki (2005) were used to modernize a kinetic scheme and to obtain the corresponding kinetic coefficients. In the new models, hydrolytic microorganisms were included using Contois kinetics for the hydrolysis/acidogenesis degradation of municipal solid waste (MSW). Monod...... kinetics was applied for description of methanogenesis. Both hydrolytic and methanogenic microorganisms were assumed to be inhibited by high volatile fatty acids (VFA) concentration. According to the new distributed models, the mixing level reduction expressed by increasing dimensionless Peclet number may...

Study on magnetic field mapping within cylindrical center volume of general magnet

Energy Technology Data Exchange (ETDEWEB)

Huang, Li; Lee, Sang Jin [Uiduk University, Gyeongju (Korea, Republic of)

2016-06-15

For the magnetic field analysis or design, it is important to know the behavior of the magnetic field in an interesting space. Magnetic field mapping becomes a useful tool for the study of magnetic field. In this paper, a numerical way for mapping the magnetic field within the cylindrical center volume of magnet is presented, based on the solution of the Laplace's equation in the cylindrical coordinate system. The expression of the magnetic field can be obtained by the magnetic flux density, which measured in the mapped volume. According to the form of the expression, the measurement points are arranged with the parallel cylindrical line (PCL) method. As example, the magnetic flux density generated by an electron cyclotron resonance ion source (ECRIS) magnet and a quadrupole magnet were mapped using the PCL method, respectively. The mapping results show the PCL arrangement method is feasible and convenience to map the magnetic field within a cylindrical center volume generated by the general magnet.

Three Dimensionally Interlinked, Dense, Solid Form of Single-Walled CNT Ropes

Science.gov (United States)

Smalley, Richard E.

2012-01-01

A 3D networked, dense form of single-walled carbon nanotubes (SWNT) has been made through isotropic shrinking of a gel-like SWNT-water paste by very slow evaporation. Approximately 35 g of Raw HiPco nanotubes were cleaned by the method of soft baking (250 C for 15 hours in air saturated with water vapor) in a glass beaker followed by leaching with concentrated hydrochloric acid. Typically, one liter of concentrated hydrochloric acid was added to the soft-baked voluminous mass in the same large beaker, and allowed to digest at room temperature with stirring overnight. The acid-digested SWNT slurry was filtered through a large porcelain Buchner funnel under atmospheric pressure. The slurry was continuously flushed, while still in the funnel, with a very slow but steady stream of deionized water employing a peristaltic pump. This process, referred to as gwashing, h continued until the filtrate water dripping from the Buchner funnel was clear, colorless, and neutral to a pH paper. This took about 15 liters of water to flow through the slurry over a day. At this point, the water pump was stopped and the SWNT-water slurry was allowed to drain the excess water for about 10 hours. The resulting thick paste of SWNT-neutral water was transferred to a beaker. The beaker was covered with aluminum foil with few holes and allowed to dry very slowly in a hood at room temperature. In about eight weeks, the sample gradually dried isotropically to a cylindrical dense mass referred to as a carbon nanotube block (CNB). There was no carbonaceous matter sticking to any of the glass surface where the SWNT-water paste made contact. The approximate dimensions of the cylindrical SWNT block that weighed 28 g were 1.5 in. (.3.8 cm) in diameter and 1.25 in. (.3.2 cm) in height. The bottom portion of the cylinder that was in contact with the beaker surface was slightly wider, indicating some resistance to shrinking. The cylindrical mass also consisted of several pores. The cylindrical mass was

Evaluation of ultrasound-assisted in situ sorbent formation solid-phase extraction method for determination of arsenic in water, food and biological samples.

Science.gov (United States)

Ezoddin, Maryam; Majidi, Behrooz; Abdi, Khosrou

2015-01-01

A simple and rapid ultrasound-assisted in situ sorbent formation solid-phase extraction (UAISFSPE) coupled with electrothermal atomic absorption spectrometry detection (ET-AAS) was developed for preconcentration and determination of arsenic (As) in various samples. A small amount of cationic surfactant is dissolved in the aqueous sample containing As ions, which were complexed by ammonium pyrrolidinedithiocarbamate After shaking, a little volume of hexafluorophosphate (NaPF6) as an ion-pairing agent was added into the solution by a microsyringe. Due to the interaction between surfactant and ion-pairing agent, solid particles are formed. The alkyl groups of the surfactant in the solid particles strongly interact with the hydrophobic groups of analytes and become bound. Sonication aids the dispersion of the sorbent into the sample solution and mass transfer of the analyte into the sorbent, thus reducing the extraction time. The solid particles are centrifuged, and the sedimented particles can be dissolved in an appropriate solvent to recover the absorbed analyte. After separation, total arsenic (As(III) and As(V)) was determined by ET-AAS. Several experimental parameters were investigated and optimized. A detection limit of 7 ng L(-1) with preconcentration factor of 100 and relative standard deviation for 10 replicate determinations of 0.1 µg L(-1) As(III) were 4.5% achieved. Consequently, the method was applied to the determination of arsenic in certified reference materials, water, food and biological samples with satisfactory results.

Free and Forced Vibrations of Thick-Walled Anisotropic Cylindrical Shells

Science.gov (United States)

Marchuk, A. V.; Gnedash, S. V.; Levkovskii, S. A.

2017-03-01

Two approaches to studying the free and forced axisymmetric vibrations of cylindrical shell are proposed. They are based on the three-dimensional theory of elasticity and division of the original cylindrical shell with concentric cross-sectional circles into several coaxial cylindrical shells. One approach uses linear polynomials to approximate functions defined in plan and across the thickness. The other approach also uses linear polynomials to approximate functions defined in plan, but their variation with thickness is described by the analytical solution of a system of differential equations. Both approaches have approximation and arithmetic errors. When determining the natural frequencies by the semi-analytical finite-element method in combination with the divide and conqure method, it is convenient to find the initial frequencies by the finite-element method. The behavior of the shell during free and forced vibrations is analyzed in the case where the loading area is half the shell thickness

Chromium speciation in environmental samples using a solid phase spectrophotometric method

Science.gov (United States)

Amin, Alaa S.; Kassem, Mohammed A.

2012-10-01

A solid phase extraction technique is proposed for preconcentration and speciation of chromium in natural waters using spectrophotometric analysis. The procedure is based on sorption of chromium(III) as 4-(2-benzothiazolylazo)2,2'-biphenyldiol complex on dextran-type anion-exchange gel (Sephadex DEAE A-25). After reduction of Cr(VI) by 0.5 ml of 96% concentrated H2SO4 and ethanol, the system was applied to the total chromium. The concentration of Cr(VI) was calculated as the difference between the total Cr and the Cr(III) content. The influences of some analytical parameters such as: pH of the aqueous solution, amounts of 4-(2-benzothiazolylazo)2,2'-biphenyldiol (BTABD), and sample volumes were investigated. The absorbance of the gel, at 628 and 750 nm, packed in a 1.0 mm cell, is measured directly. The molar absorptivities were found to be 2.11 × 107 and 3.90 × 107 L mol-1 cm-1 for 500 and 1000 ml, respectively. Calibration is linear over the range 0.05-1.45 μg L-1 with RSD of <1.85% (n = 8.0). Using 35 mg exchanger, the detection and quantification limits were 13 and 44 ng L-1 for 500 ml sample, whereas for 1000 ml sample were 8.0 and 27 ng L-1, respectively. Increasing the sample volume can enhance the sensitivity. No considerable interferences have been observed from other investigated anions and cations on the chromium speciation. The proposed method was applied to the speciation of chromium in natural waters and total chromium preconcentration in microwave digested tobacco, coffee, tea, and soil samples. The results were simultaneously compared with those obtained using an ET AAS method, whereby the validity of the method has been tested.

Investigation on Surface Roughness in Cylindrical Grinding

Science.gov (United States)

Rudrapati, Ramesh; Bandyopadhyay, Asish; Pal, Pradip Kumar

2011-01-01

Cylindrical grinding is a complex machining process. And surface roughness is often a key factor in any machining process while considering the machine tool or machining performance. Further, surface roughness is one of the measures of the technological quality of the product and is a factor that greatly influences cost and quality. The present work is related to some aspects of surface finish in the context of traverse-cut cylindrical grinding. The parameters considered have been: infeed, longitudinal feed and work speed. Taguchi quality design is used to design the experiments and to identify the significantly import parameter(s) affecting the surface roughness. By utilization of Response Surface Methodology (RSM), second order differential equation has been developed and attempts have also been made for optimization of the process in the context of surface roughness by using C- programming.

Acoustic characteristics of sand sediment with circular cylindrical pores

International Nuclear Information System (INIS)

Roh, Heui-Seol; Lee, Kang-Il; Yoon, Suk-Wang

2004-01-01

The acoustic pressure transmission coefficient and the phase velocity are experimentally measured as functions of the frequency and the porosity in sand sediment slabs with circular cylindrical pores filled with water and air. They are also theoretically estimated with the modified Biot-Attenborough (MBA) model, which uses a separate treatment of the viscous and the thermal effects in a non-rigid porous medium with water- and air-filled cylindrical pores. In this study, the fast (first kind) wave and the slow (second kind) wave are not separated in the transmitted signals through a sediment slab without the circular cylindrical pores, but they are separated in the transmitted signals through a sediment slab with pores. Both the phase velocities and the transmission coefficients of the fast wave and the slow wave in the sediment slabs with water- and air-filled cylindrical pores are sensitive to the air and the water porosities. It is proposed that the fast and the slow waves have opposite behaviors for several acoustic characteristics. The generalized tortuosity factor and the dynamic shape factor are introduced from the acoustic characteristics of the fast wave. The experimental results show reasonable agreement with the theoretical results estimated with the MBA model. These results suggest the possibility of predicting the acoustic characteristics of a sediment as functions of arbitrary water and air porosities. This study may also be applicable to understanding acoustic wave propagations in a bubbly liquid sediment for underwater applications and in cancellous bone for the diagnosis of osteoporosis.

Plasma waves in an inhomogeneous cylindrical plasma

International Nuclear Information System (INIS)

Pesic, S.S.

1976-01-01

The complete dispersion equation governing small amplitude plasma waves propagating in an inhomogeneous cylindrical plasma confined by a helical magnetic field is solved numerically. The efficiency of the wave energy thermalization in the lower hybrid frequency range is studied

Effect of laser beam on temperature distribution on artificial cylindrical shaped hard tissue bones

Science.gov (United States)

Al-Akhras, M.-Ali H.; Qaseer, Mohammad-Khair; Albiss, B. A.; Gezawa, Umar S.

2018-02-01

Samples from fresh lamb chest bones were made in cylindrical shapes to study the time variation of temperature T as functions of the cylindrical radius and depth when its front surface exposed to a laser beam of 110Mw power and 642nm wavelength. The laser beam was directed at the center of the front surface of the horizontal cylinder. The measurements were done in vacuum and at atmospheric pressure. Our data reveal the linear variation of T with time, followed by a gradual increase before it reaches a plateau value at higher time. This sort of behavior independent of the radius or the depth where the temperature was measured. Moreover, the maximum variation occurs on the front surface where the laser beam was hitting and diminishes gradually with depth deep inside the cylinder. Data at atmospheric pressure showed less changes in temperature. The temperature distribution in bone due to laser irradiation is very important for a rational use of laser therapy as well as in the surgery to minimizes the thermal tissue damage.

Penetration of sub-micron aerosol droplets in composite cylindrical filtration elements

International Nuclear Information System (INIS)

Geurts, Bernard J.; Pratte, Pascal; Stolz, Steffen; Stabbert, Regina; Poux, Valerie; Nordlund, Markus; Winkelmann, Christoph

2011-01-01

Advection-diffusion transport of aerosol droplets in composite cylindrical filtration elements is analyzed and compared to experimental data. The penetration, characterizing the fraction of droplets that passes through the pores of a filtration element, is quantified for a range of flow rates. The advection-diffusion transport in a laminar Poiseuille flow is treated numerically for slender pores using a finite difference approach in cylindrical coordinates. The algebraic dependence of the penetration on the Peclet number as predicted theoretically, is confirmed by experimental findings at a variety of aspect ratios of the cylindrical pores. The effective penetration associated with a composite filtration element consisting of a set of parallel cylindrical pores is derived. The overall penetration of heterogeneous composite filtration elements shows an algebraic dependence to the fourth power on the radii of the individual pores that are contained. This gives rise to strong variations in the overall penetration in cases with uneven distributions of pore sizes, highly favoring filtration by the larger pores. The overall penetration is computed for a number of basic geometries, providing a point of reference for filtration design and experimental verification.

Solid phase extraction for the speciation and preconcentration of inorganic selenium in water samples: a review.

Science.gov (United States)

Herrero Latorre, C; Barciela García, J; García Martín, S; Peña Crecente, R M

2013-12-04

Selenium is an essential element for the normal cellular function of living organisms. However, selenium is toxic at concentrations of only three to five times higher than the essential concentration. The inorganic forms (mainly selenite and selenate) present in environmental water generally exhibit higher toxicity (up to 40 times) than organic forms. Therefore, the determination of low levels of different inorganic selenium species in water is an analytical challenge. Solid-phase extraction has been used as a separation and/or preconcentration technique prior to the determination of selenium species due to the need for accurate measurements for Se species in water at extremely low levels. The present paper provides a critical review of the published methods for inorganic selenium speciation in water samples using solid phase extraction as a preconcentration procedure. On the basis of more than 75 references, the different speciation strategies used for this task have been highlighted and classified. The solid-phase extraction sorbents and the performance and analytical characteristics of the developed methods for Se speciation are also discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Spherical and cylindrical particle resonator as a cloak system

Science.gov (United States)

Minin, I. V.; Minin, O. V.; Eremeev, A. I.; Tseplyaev, I. S.

2018-05-01

The concept of dielectric spherical or cylindrical particle in resonant mode as a cloak system is offered. In fundamental modes (modes with the smallest volume correspond to |m| = l, and s = 1) the field is concentrated mostly in the equatorial plane and at the surface of the sphere. Thus under resonance modes, such perturbation due to cuboid particle inserted in the spherical or cylindrical particle has almost no effect on the field forming resonance regardless of the value of internal particle material (defect) as long as this material does not cover the region where resonance takes place.

Gravitational collapse of a cylindrical null shell in vacuum

Directory of Open Access Journals (Sweden)

S. Khakshournia

2008-03-01

Full Text Available   Barrabès-Israel null shell formalism is used to study the gravitational collapse of a thin cylindrical null shell in vacuum. In general the lightlike matter shell whose history coincides with a null hypersurface is characterized by a surface energy density. In addition, a gravitational impulsive wave is present on this null hypersurface whose generators admit both the shear and expansion. In the case of imposing the cylindrical flatness the surface energy-momentum tensor of the matter shell on the null hypersurface vanishes and the null hyper- surface is just the history of the gravitational wave .

Flux pinning characteristics in cylindrical ingot niobium used in superconducting radio frequency cavity fabrication

Energy Technology Data Exchange (ETDEWEB)

Dhavale Ashavai, Pashupati Dhakal, Anatolii A Polyanskii, Gianluigi Ciovati

2012-04-01

We present the results of from DC magnetization and penetration depth measurements of cylindrical bulk large-grain (LG) and fine-grain (FG) niobium samples used for the fabrication of superconducting radio frequency (SRF) cavities. The surface treatment consisted of electropolishing and low temperature baking as they are typically applied to SRF cavities. The magnetization data were fitted using a modified critical state model. The critical current density Jc and pinning force Fp are calculated from the magnetization data and their temperature dependence and field dependence are presented. The LG samples have lower critical current density and pinning force density compared to FG samples which implies a lower flux trapping efficiency. This effect may explain the lower values of residual resistance often observed in LG cavities than FG cavities.

Flux dynamics and magnetovoltage measurements in a macroscopic cylindrical hole drilled in BSCCO

Energy Technology Data Exchange (ETDEWEB)

Yetis, H.; Altinkok, A.; Olutas, M. [Abant Izzet Baysal University, Department of Physics, Turgut Gulez Research Laboratory, 14280 Bolu (Turkey); Kilic, A. [Abant Izzet Baysal University, Department of Physics, Turgut Gulez Research Laboratory, 14280 Bolu (Turkey)], E-mail: kilic_a@ibu.edu.tr; Kilic, K. [Abant Izzet Baysal University, Department of Physics, Turgut Gulez Research Laboratory, 14280 Bolu (Turkey)

2007-10-01

Slow transport relaxation measurements (V-t curves) and magnetovoltage measurements (V-H curves) were carried out in a polycrystalline sample of Bi{sub 1.7}Pb{sub 0.3}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} (BSCCO) with a macroscopic cylindrically drilled hole (CH). The time evolution of quenched state in V-t curves was interpreted in terms of enhancement of the superconducting order parameter and the relaxation of moving entity. Upon cycling of the external magnetic field with different sweep rates, unusual counter clockwise hysteresis effects and asymmetry in V-H curves are observed in BSCCO sample with CH, which can also be correlated to the trapping of the macroscopic flux bundles in CH.

Analysis on Forced Vibration of Thin-Wall Cylindrical Shell with Nonlinear Boundary Condition

Directory of Open Access Journals (Sweden)

Qiansheng Tang

2016-01-01

Full Text Available Forced vibration of thin-wall cylindrical shell under nonlinear boundary condition was discussed in this paper. The nonlinear boundary was modeled as supported clearance in one end of shell and the restraint was assumed as linearly elastic in the radial direction. Based on Sanders’ shell theory, Lagrange equation was utilized to derive the nonlinear governing equations of cylindrical shell. The displacements in three directions were represented by beam functions and trigonometric functions. In the study of nonlinear dynamic responses of thin-wall cylindrical shell with supported clearance under external loads, the Newmark method is used to obtain time history, frequency spectrum plot, phase portraits, Poincare section, bifurcation diagrams, and three-dimensional spectrum plot with different parameters. The effects of external loads, supported clearance, and support stiffness on nonlinear dynamics behaviors of cylindrical shell with nonlinear boundary condition were discussed.

Nonlinear elastic inclusions in isotropic solids

KAUST Repository

Yavari, A.

2013-10-16

We introduce a geometric framework to calculate the residual stress fields and deformations of nonlinear solids with inclusions and eigenstrains. Inclusions are regions in a body with different reference configurations from the body itself and can be described by distributed eigenstrains. Geometrically, the eigenstrains define a Riemannian 3-manifold in which the body is stress-free by construction. The problem of residual stress calculation is then reduced to finding a mapping from the Riemannian material manifold to the ambient Euclidean space. Using this construction, we find the residual stress fields of three model systems with spherical and cylindrical symmetries in both incompressible and compressible isotropic elastic solids. In particular, we consider a finite spherical ball with a spherical inclusion with uniform pure dilatational eigenstrain and we show that the stress in the inclusion is uniform and hydrostatic. We also show how singularities in the stress distribution emerge as a consequence of a mismatch between radial and circumferential eigenstrains at the centre of a sphere or the axis of a cylinder.

Sampling, characterisation and processing of solid recovered fuel production from municipal solid waste: An Italian plant case study.

Science.gov (United States)

Ranieri, Ezio; Ionescu, Gabriela; Fedele, Arcangela; Palmieri, Eleonora; Ranieri, Ada Cristina; Campanaro, Vincenzo

2017-08-01

This article presents the classification of solid recovered fuel from the Massafra municipal solid waste treatment plant in Southern Italy in compliancy with the EN 15359 standard. In order to ensure the reproducibility of this study, the characterisation methods of waste input and output flow, the mechanical biological treatment line scheme and its main parameters for each stage of the processing chain are presented in details, together with the research results in terms of mass balance and derived fuel properties. Under this study, only 31% of refused municipal solid waste input stream from mechanical biological line was recovered as solid recovered fuel with a net heating value (NC=HV) average of 15.77 MJ kg -1 ; chlorine content average of 0.06% on a dry basis; median of mercury solid recovered fuel produced meets the European Union standard requirements and can be classified with the class code: Net heating value (3); chlorine (1); mercury (1).

Effect of perforation on the sound transmission through a double-walled cylindrical shell

Science.gov (United States)

Zhang, Qunlin; Mao, Yijun; Qi, Datong

2017-12-01

An analytical model is developed to study the sound transmission loss through a general double-walled cylindrical shell system with one or two walls perforated, which is excited by a plane wave in the presence of external mean flow. The shell motion is governed by the classical Donnell's thin shell theory, and the mean particle velocity model is employed to describe boundary conditions at interfaces between the shells and fluid media. In contrast to the conventional solid double-walled shell system, numerical results show that perforating the inner shell in the transmission side improves sound insulation performance over a wide frequency band, and removes fluctuation of sound transmission loss with frequency at mid-frequencies in the absence of external flow. Both the incidence and azimuthal angles have nearly negligible effect on the sound transmission loss over the low and middle frequency range when perforating the inner shell. Width of the frequency band with continuous sound transmission loss can be tuned by the perforation ratio.

Errors due to the cylindrical cell approximation in lattice calculations

Energy Technology Data Exchange (ETDEWEB)

Newmarch, D A [Reactor Development Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

1960-06-15

It is shown that serious errors in fine structure calculations may arise through the use of the cylindrical cell approximation together with transport theory methods. The effect of this approximation is to overestimate the ratio of the flux in the moderator to the flux in the fuel. It is demonstrated that the use of the cylindrical cell approximation gives a flux in the moderator which is considerably higher than in the fuel, even when the cell dimensions in units of mean free path tend to zero; whereas, for the case of real cells (e.g. square or hexagonal), the flux ratio must tend to unity. It is also shown that, for cylindrical cells of any size, the ratio of the flux in the moderator to flux in the fuel tends to infinity as the total neutron cross section in the moderator tends to zero; whereas the ratio remains finite for real cells. (author)

A Novel Automated Method for Analyzing Cylindrical Computed Tomography Data

Science.gov (United States)

Roth, D. J.; Burke, E. R.; Rauser, R. W.; Martin, R. E.

2011-01-01

A novel software method is presented that is applicable for analyzing cylindrical and partially cylindrical objects inspected using computed tomography. This method involves unwrapping and re-slicing data so that the CT data from the cylindrical object can be viewed as a series of 2-D sheets in the vertical direction in addition to volume rendering and normal plane views provided by traditional CT software. The method is based on interior and exterior surface edge detection and under proper conditions, is FULLY AUTOMATED and requires no input from the user except the correct voxel dimension from the CT scan. The software is available from NASA in 32- and 64-bit versions that can be applied to gigabyte-sized data sets, processing data either in random access memory or primarily on the computer hard drive. Please inquire with the presenting author if further interested. This software differentiates itself in total from other possible re-slicing software solutions due to complete automation and advanced processing and analysis capabilities.

Electrostatic resonances and optical responses of cylindrical clusters

International Nuclear Information System (INIS)

Choy, C W; Xiao, J J; Yu, K W

2008-01-01

We developed a Green function formalism (GFF) for computing the electrostatic resonance in clusters of cylindrical particles. In the GFF, we take advantage of a surface integral equation to avoid matching the complicated boundary conditions on the surfaces of the particles. Numerical solutions of the eigenvalue equation yield a pole spectrum in the spectral representation. The pole spectrum can in turn be used to compute the optical response of these particles. For two cylindrical particles, the results are in excellent agreement with the exact results from the multiple image method and the normal mode expansion method. The results of this work can be extended to investigate the enhanced nonlinear optical responses of metal-dielectric composites, as well as optical switching in plasmonic waveguides.

Vertical load analysis of cylindrical ACS support structures

International Nuclear Information System (INIS)

Kennedy, J.M.; Belytschko, T.B.

1984-01-01

A new concept in LMFBR design ACS (above-core structures) supports which has generated some interest is to use a single large radius cylinder. The advantages of a single cylinder are reduced cost of fabrication, increased lateral stiffness, which enhances seismic resistance, and easier access to the fuel. However, the performance of these support structures when submitted to vertical loads from the core area may be substantially different, for the buckling and postbuckling behavior of a cylinder differs substantially from that of cylindrical beams. In this paper, a comparative analysis of an old prototypical support by 4 columns is compared with a cylindrical support. It is assumed that the single cylinder replaces the 4 columns in the original design. The dimensions of the two designs are compared

Magnetization curves for general cylindrical samples in a transverse ...

Indian Academy of Sciences (India)

The method uses the technique of conformal mapping to express the sample surface and the flux-fronts in terms of a set of coefficients that depend on a parameter. The flux-fronts are to be determined by solving a system of nonlinear ordinary differential equations for the coefficients. Retaining only a certain finite number of ...

Cracking of anisotropic cylindrical polytropes

Energy Technology Data Exchange (ETDEWEB)

Mardan, S.A. [University of the Management and Technology, Department of Mathematics, Lahore (Pakistan); Azam, M. [University of Education, Division of Science and Technology, Lahore (Pakistan)

2017-06-15

We study the appearance of cracking in charged anisotropic cylindrical polytropes with generalized polytropic equation. We investigate the existence of cracking in two different kinds of polytropes existing in the literature through two different assumptions: (a) local density perturbation with conformally flat condition, and (b) perturbing polytropic index, charge and anisotropy parameters. We conclude that cracking appears in both kinds of polytropes for a specific range of density and model parameters. (orig.)

Method of dismantling cylindrical structure by cutting

International Nuclear Information System (INIS)

Harada, Minoru; Mitsuo, Kohei; Yokota, Isoya; Nakamura, Kenjiro.

1989-01-01

This invention concerns a method of cutting and removing cylindrical structures, for example, iron-reinforced concrete materials such as thermal shielding walls in BWR type power plants into block-like form. That is, in a method of cutting and removing the cylindrical structure from the side of the outer wall, the structural material is cut from above to below successively in the axial direction and the circumferential direction by means abrasive jet by remote operation and cut into blocks each of a predetermined size. The cut out blocks are successively taken out. Cutting of the material from above to below by remote operation and taking out of small blocks causes no hazards to human body. Upon practicing the present invention, it is preferred to use a processing device for slurry and exhaust gases for preventing scattering of activated dismantled pieces or powdery dusts. (K.M.)

Digital Cellular Solid Pressure Vessels: A Novel Approach for Human Habitation in Space

Science.gov (United States)

Cellucci, Daniel; Jenett, Benjamin; Cheung, Kenneth C.

2017-01-01

It is widely assumed that human exploration beyond Earth's orbit will require vehicles capable of providing long duration habitats that simulate an Earth-like environment - consistent artificial gravity, breathable atmosphere, and sufficient living space- while requiring the minimum possible launch mass. This paper examines how the qualities of digital cellular solids - high-performance, repairability, reconfigurability, tunable mechanical response - allow the accomplishment of long-duration habitat objectives at a fraction of the mass required for traditional structural technologies. To illustrate the impact digital cellular solids could make as a replacement to conventional habitat subsystems, we compare recent proposed deep space habitat structural systems with a digital cellular solids pressure vessel design that consists of a carbon fiber reinforced polymer (CFRP) digital cellular solid cylindrical framework that is lined with an ultra-high molecular weight polyethylene (UHMWPE) skin. We use the analytical treatment of a linear specific modulus scaling cellular solid to find the minimum mass pressure vessel for a structure and find that, for equivalent habitable volume and appropriate safety factors, the use of digital cellular solids provides clear methods for producing structures that are not only repairable and reconfigurable, but also higher performance than their conventionally manufactured counterparts.

Measurement of radon exhalation rates in some soil samples collected near the international monument Taj Mahal, Agra

International Nuclear Information System (INIS)

Sharma, Jyoti; Kumar, Rupesh; Indolia, R.S.; Swarup, R.; Mahur, A.K.; Singh, Hargyan; Sonkawade, R.G.

2011-01-01

Human beings are exposed to ionizing radiation from natural sources due to the occurrence of natural radioactive elements in solids, rocks, sand, soil etc. used as building construction materials and to the internal exposure from radioactive elements through good, water and air. Radon exhalation rate is of prime importance for the estimation of radiation risk from various materials. In the present study soil samples collected near the Tajmahal Agra. Sealed Can Technique was adopted for radon exhalation measurements. All the soil samples collected were grinded, dried and sieved through a 100 mesh sieve. Equal amount of each sieved (100μm grain size) sample (100 gm) was placed at the base of the Cans of 7.5 cm height and 7.0 cm diameter similar to those used in the calibration experiment (Singh et al., 1997). LR-115 type II plastic track detector (2 cm x 2 cm) was fixed on the top inside of the cylindrical Can. Radon exhalation rate varies from 529 mBqm -2 h -1 to 1254 mBqm -2 h -1 . The results will be presented. (author)

A mathematical model of microalgae growth in cylindrical photobioreactor

Science.gov (United States)

Bakeri, Noorhadila Mohd; Jamaian, Siti Suhana

2017-08-01

Microalgae are unicellular organisms, which exist individually or in chains or groups but can be utilized in many applications. Researchers have done various efforts in order to increase the growth rate of microalgae. Microalgae have a potential as an effective tool for wastewater treatment, besides as a replacement for natural fuel such as coal and biodiesel. The growth of microalgae can be estimated by using Geider model, which this model is based on photosynthesis irradiance curve (PI-curve) and focused on flat panel photobioreactor. Therefore, in this study a mathematical model for microalgae growth in cylindrical photobioreactor is proposed based on the Geider model. The light irradiance is the crucial part that affects the growth rate of microalgae. The absorbed photon flux will be determined by calculating the average light irradiance in a cylindrical system illuminated by unidirectional parallel flux and considering the cylinder as a collection of differential parallelepipeds. Results from this study showed that the specific growth rate of microalgae increases until the constant level is achieved. Therefore, the proposed mathematical model can be used to estimate the rate of microalgae growth in cylindrical photobioreactor.

Effect of Melt Convection and Solid Transport on Macrosegregation and Grain Structure in Equiaxed Al-Cu Alloys

Science.gov (United States)

Rerko, Rodney S.; deGroh, Henry C., III; Beckermann, Christoph; Gray, Hugh R. (Technical Monitor)

2002-01-01

Macrosegregation in metal casting can be caused by thermal and solutal melt convection, and the transport of unattached solid crystals. These free grains can be a result of, for example, nucleation in the bulk liquid or dendrite fragmentation. In an effort to develop a comprehensive numerical model for the casting of alloys, an experimental study has been conducted to generate benchmark data with which such a solidification model could be tested. The specific goal of the experiments was to examine equiaxed solidification in situations where sinking of grains is (and is not) expected. The objectives were: 1) experimentally study the effects of solid transport and thermosolutal convection on macrosegregation and grain size distribution patterns; and 2) provide a complete set of controlled thermal boundary conditions, temperature data, segregation data, and grain size data, to validate numerical codes. The alloys used were Al-1 wt. pct. Cu, and Al-10 wt. pct. Cu with various amounts of the grain refiner TiB2 added. Cylindrical samples were either cooled from the top, or the bottom. Several trends in the data stand out. In attempting to model these experiments, concentrating on experiments that show clear trends or differences is recommended.

Resonant Excitation of a Truncated Metamaterial Cylindrical Shell by a Thin Wire Monopole

DEFF Research Database (Denmark)

Kim, Oleksiy S.; Erentok, Aycan; Breinbjerg, Olav

2009-01-01

A truncated metamaterial cylindrical shell excited by a thin wire monopole is investigated using the integral equation technique as well as the finite element method. Simulations reveal a strong field singularity at the edge of the truncated cylindrical shell, which critically affects the matching...

Design of a cylindrical LED substrate without radiator

Science.gov (United States)

Tang, Fan; Guo, Zhenning

2017-12-01

To reduce the weight and production costs of light-emitting diode (LED) lamps, we applied the principle of the chimney effect to design a cylindrical LED substrate without a radiator. We built a 3D model by using Solidworks software and applied the flow simulation plug-in to conduct model simulation, thereby optimizing the heat source distribution and substrate thickness. The results indicate that the design achieved optimal cooling with a substrate with an upper extension length of 35 mm, a lower extension length of 8 mm, and a thickness of 1 mm. For a substrate of those dimensions, the highest LED chip temperature was 64.78 °C, the weight of the substrate was 35.09 g, and R jb = 7.00 K/W. If the substrate is powered at 8, 10, and 12 W, its temperature meets LED safety requirements. In physical tests, the highest temperature for a physical 8 W cylindrical LED substrate was 66 °C, which differed by only 1.22 °C from the simulation results, verifying the validity of the simulation. The designed cylindrical LED substrate can be used in high-power LED lamps that do not require radiators. This design is not only excellent for heat dissipation, but also for its low weight, low cost, and simplicity of manufacture.

Cylindrical polymer brushes with dendritic side chains by iterative anionic reactions

KAUST Repository

Zhang, Hefeng

2015-05-01

We report in this paper an easy method for the synthesis of cylindrical polymer brushes with dendritic side chains through anionic reaction. The synthesis is accomplished by iteratively grafting a living block copolymer, polyisoprene-. b-polystyrenyllithium (PI-. b-PSLi), to the main chain and subsequently to the branches in a divergent way. PI segment is short and serves as a precursor for multifunctional branching unit. The grafting reaction involves two successive steps: i) epoxidation of internal double bonds of PI segments, either in main chain or side chains; ii) ring-opening addition to the resulting epoxy group by the living PI-. b-PSLi. Repeating the two steps affords a series of cylindrical polymer brushes with up to 3rd generation and extremely high molecular weight. The branching multiplicity depends on the average number of oxirane groups per PI segment, usually ca. 8 in the present work. The high branching multiplicity leads to tremendous increase in molecular weights of the cylindrical products with generation growth. Several series of cylindrical polymer brushes with tunable aspect ratios are prepared using backbones and branches with controlled lengths. Shape anisotropy is investigated in dilute solution using light scattering technique. Worm-like single molecular morphology with large persistence length is observed on different substrates by atomic force microscopy.

Experiments on cylindrically converging blast waves in atmospheric air

Science.gov (United States)

Matsuo, Hideo; Nakamura, Yuichi

1980-06-01

Cylindrically converging blast waves have been produced in normal atmospheric conditions by the detonation of the explosives, pentaerythritoltetranitrate, (PETN), over cylindrical surfaces. The shocks generated in this way are so strong that the fronts propagating through the air become luminous of themselves. The production and the propagation of the shocks have been monitored with a framing camera and a streak camera, and the time-space relations of the shock propagations have been determined using an electrical ionization probing system. The results have shown that the trajectory of the shock fronts near the axis of the cylinder can be approximately represented by the Guderley's formula.

Metallurgical Evaluation of the Five-Inch Cylindrical Induction Melter

International Nuclear Information System (INIS)

Imrich, K.J.

2000-01-01

A metallurgical evaluation of the 5-inch cylindrical induction melter (CIM) vessel was performed by the Materials Technology Section to evaluate the metallurgical condition after operating for approximately 375 hours at 1400 to 1500 Degrees Celsius during a 2 year period. Results indicate that wall thinning and significant grain growth occurred in the lower portion of the conical section and the drain tube. No through-wall penetrations were found in the cylindrical and conical sections of the CIM vessel and only one leak site was identified in the drain tube. Failure of the drain tube was associated with a localized over heating and intercrystalline fracture

Dynamics of charged viscous dissipative cylindrical collapse with full causal approach

Energy Technology Data Exchange (ETDEWEB)

Shah, S.M.; Abbas, G. [The Islamia University of Bahawalpur, Department of Mathematics, Bahawalpur (Pakistan)

2017-11-15

The aim of this paper is to investigate the dynamical aspects of a charged viscous cylindrical source by using the Misner approach. To this end, we have considered the more general charged dissipative fluid enclosed by the cylindrical symmetric spacetime. The dissipative nature of the source is due to the presence of dissipative variables in the stress-energy tensor. The dynamical equations resulting from such charged cylindrical dissipative source have been coupled with the causal transport equations for heat flux, shear and bulk viscosity, in the context of the Israel-Steward theory. In this case, we have the considered Israel-Steward transportation equations without excluding the thermodynamics viscous/heat coupling coefficients. The results are compared with the previous works in which such coefficients were excluded and viscosity variables do not satisfy the casual transportation equations. (orig.)

Are Flow Injection-based Approaches Suitable for Automated Handling of Solid Samples?

DEFF Research Database (Denmark)

Miró, Manuel; Hansen, Elo Harald; Cerdà, Victor

Flow-based approaches were originally conceived for liquid-phase analysis, implying that constituents in solid samples generally had to be transferred into the liquid state, via appropriate batch pretreatment procedures, prior to analysis. Yet, in recent years, much effort has been focused...... electrolytic or aqueous leaching, on-line dialysis/microdialysis, in-line filtration, and pervaporation-based procedures have been successfully implemented in continuous flow/flow injection systems. In this communication, the new generation of flow analysis, including sequential injection, multicommutated flow.......g., soils, sediments, sludges), and thus, ascertaining the potential mobility, bioavailability and eventual impact of anthropogenic elements on biota [2]. In this context, the principles of sequential injection-microcolumn extraction (SI-MCE) for dynamic fractionation are explained in detail along...

Preparation of solid-state samples of a transition metal coordination compound for synchrotron radiation photoemission studies

CERN Document Server

Crotti, C; Celestino, T; Fontana, S

2003-01-01

The aim of this research was to identify a sample preparation method suitable for the study of transition metal complexes by photoemission spectroscopy with synchrotron radiation as the X-ray source, even in the case where the compound is not evaporable. Solid-phase samples of W(CO) sub 4 (dppe) [dppe=1,2-bis(diphenylphosphino)ethane] were prepared according to different methods and their synchrotron radiation XPS spectra measured. The spectra acquired from samples prepared by spin coating show core level peaks only slightly broader than the spectrum recorded from UHV evaporated samples. Moreover, for these samples the reproducibility of the binding energy values is excellent. The dependence of the spin coating technique on parameters such as solvent and solution concentration, spinning speed and support material was studied. The same preparation method also allowed the acquisition of valence band spectra, the main peaks of which were clearly resolved. The results suggest that use of the spin coating techniqu...

Liquid-solid extraction of uranium (VI) with TOPO - molten naphthalene and determination by laser fluorimetry in geological samples

International Nuclear Information System (INIS)

Kumar, Sanjay; Krishnakumar, M.; Patwardhan, A.A.

2007-01-01

A simple, rapid, sensitive, cost-effective and efficient method for separation of uranium using tri-n-octylphosphine oxide (TOPO)-molten naphthalene as solid phase extractant and its determination by laser fluorimetry in geological samples (rock, soil, sediment) was developed. Under optimum conditions, using 50 mg TOPO and 100 mg naphthalene, 50 - 5000 ng of uranium in 10 ml sample solution (3% (v/v) HNO 3 ) could be extracted quantitatively. The extracted uranium was stripped using tetra sodium pyrophosphate (5% (v/v) solution, pH adjusted to 7.0 with H 3 PO 4 ) and determined by laser fluorimetry. The influence of different acid concentrations, the amount of solid phase extractant, sample volumes, different stripping reagents, their volumes and effect of foreign ions on the extraction and determination of uranium (VI) were investigated. Synthetic samples of varying concentration as regards uranium were prepared and analysed. Recoveries ranging from 90% to 105% were obtained. The method was validated by analyzing four certified reference materials namely, BL-5, DH-1a, SY-2, SY-3 and the values obtained for uranium agreed well with the certified values. The method was also applied to the determination of uranium in geological samples (rock, soil and sediment) by laser fluorimetry and the results obtained compared favorably with those obtained from the pellet fluorimetry method. Following the proposed method, determination limit for uranium was found to be 1 μg/g with RSD ± 10%. (author)

A long-term validation of the modernised DC-ARC-OES solid-sample method.

Science.gov (United States)

Flórián, K; Hassler, J; Förster, O

2001-12-01

The validation procedure based on ISO 17025 standard has been used to study and illustrate both the longterm stability of the calibration process of the DC-ARC solid sample spectrometric method and the main validation criteria of the method. In the calculation of the validation characteristics depending on the linearity(calibration), also the fulfilment of predetermining criteria such as normality and homoscedasticity was checked. In order to decide whether there are any trends in the time-variation of the analytical signal or not, also the Neumann test of trend was applied and evaluated. Finally, a comparison with similar validation data of the ETV-ICP-OES method was carried out.

Monitoring and Method development of Hg in Istanbul Airborne Particulates by Solid Sampling Continuum Source-High Resolution Electrothermal Atomic Absorption Spectromerty

Directory of Open Access Journals (Sweden)

Soydemir E.

2014-07-01

Full Text Available In this work, a method has been developed and monitoring for the determination of mercury in PM2.5 airborne particulates by solid sampling high-resolution continuum source electrothermal atomic absorption spectrometry. The PM2.5 airborne particulates were collected on quartz filters using high volume samplers (500 L/min in Istanbul (Turkey for 96 hours every month in one year. At first, experimental conditions as well as the validation tests were optimized using collected filter. For this purpose, the effects of atomization temperature, amount of sample intoduced in to the furnace, addition of acids and/or KMnO4 on the sample, covering of graphite tube and platform or using of Ag nanoparticulates, Au nanoparticulates, and Pd solutions on the accuracy and precision were investigated. After optimization of the experimental conditions, the mercury concentrations were determined in the collected filter. The filters with PM2.5 airborne particulates were dried, divided into small fine particles and then Hg concentrations were determined directly. In order to eliminate any error due to the sensitivity difference between aqueous standards and solid samples, the quantification was performed using solid calibrants. The limit of detection, based on three times the standard deviations for ten atomizations of an unused filter, was 30 ng/g. The Hg content was dependent on the sampling site, season etc, ranging from samples, addition of AuNPs, AgNPs and Pd solution for amalgamation effects on the recoveries were investigated. The results were compared using statistical tests.

Absolute and intrinsic response probabilities of scintillators presenting straight truncated cylindrical geometries to photons imitted by sources of the same shape

International Nuclear Information System (INIS)

Becker, A.; Gorry, J.; Lame, J.

1984-07-01

Many ''sources'' of radioactive substances possess cylindrical geometry (waste drums for example) and gamma spectrometric detectors, as far as their active (selective) elements are concerned, are generally characterised by rotational symmetry about an axis. Such a situation may offer an analytical approach to the determination of the response of a cylindrical detector to a radiation produced homogeneously in a cylindrical emitter. Owing to the selective possibilities of spectrometry (in particular photoelectric effect) it is possible to reason purely in terms of transmission and absorption, which allows a formulation of the kind encountered in geometrical optics. In the present text we have developed the analytical expression beyond the limits from which most articles dealing with similar subjects have employed random sampling integration. Using a coaxial set-up in all cases, but with various relative dimensions of the right cylinder trunks (emitters and receivers), we have extracted fourfold definite integrals (with certain variable limits) giving the absolute and intrinsic efficiencies of which the ratios could be optimised by appropriate relative sizing of the right cylinder trunks (emission and detection) [fr

Strain solitons in solids and how to construct them

CERN Document Server

Samsonov, Alexander M

2001-01-01

Although the theory behind solitary waves of strain shows that they hold significant promise in nondestructive testing and a variety of other applications, an enigma has long persisted-the absence of observable elastic solitary waves in practice. Inspired by this apparent contradiction, Strain Solitons in Solids and How to Construct Them refines the existing theory, explores how to construct a powerful deformation pulse in a waveguide without plastic flow or fracture, and proposes a direct method of strain soliton generation, detection, and observation.The author focuses on the theory, simulation, generation, and propagation of strain solitary waves in a nonlinearly elastic, straight cylindrical rod under finite deformations. He introduces the general theory of wave propagation in nonlinearly elastic solids and shows, from first principles, how its main ideas can lead to successful experiments. In doing so, he develops a new approach to solving the corresponding doubly dispersive equation (DDE) with dissipati...

Digital image processing: Cylindrical surface plane development of CAREM fuel pellets

International Nuclear Information System (INIS)

Caccavelli, J; Cativa Tolosa, S; Gommes, C

2012-01-01

As part of the development of fuel pellets (FPs) for nuclear reactor CAREM-25, is necessary to systematize the analysis of the mechanical integrity of the FPs that is now done manually by a human operator. Following specifications and standards of reference for this purpose, the FPs should be inspected visually for detecting material discontinuities in the FPs surfaces to minimize any deterioration, loss of material and excessive breakage during operation and load of fuel bars. The material discontinuities are classified into two defects: surface cracks and chips. For each of these surface defects exist acceptance criteria that determine if the fuel pellet (FP) as a whole is accepted or rejected. One criteria for surface cracks is that they do not exceed one third (1/3) of the circumferential surface of the FP. The FP has cylindrical shape, so some of these acceptance criteria make difficult to analyze the FP in a single photographic image. Depending on the axial rotation of the FP, the crack could not be entirely visualized on the picture frame. Even a single crack that appears in different parts of the FP rotated images may appear to be different cracks in the FP when it is actually one. For this reason it is necessary, for the automatic detection and measurement of surface defects, obtain the circumferential surface of the FP into a single image in order to decide the acceptance or reject of the FP. As the FP shape is cylindrical, it is possible to obtain the flat development of the cylindrical surface (surface unrolling) of the FPs into a single image combining the image set of the axial rotation of the FP. In this work, we expose the procedure to implement the flat development of the cylindrical surface (surface unrolling). Starting from a photographic image of the FP surface, which represents the projection of a cylinder in the plane, we obtain three-dimensional information of each point on the cylindrical surface of the FP (3D-mapping). Then, we can

Ion currents to cylindrical Langmuir probes for finite ion temperature values: Theory

International Nuclear Information System (INIS)

Ballesteros, J.; Palop, J.I.F.; Colomer, V.; Hernandez, M.A.

1995-01-01

As it is known, the experimental ion currents to a cylindrical Langmuir probe fit quite well to the radial motion theory, developed by Allen, Boyd and Reynolds (ABR Model) and generalized by Chen for the cylindrical probe case. In this paper, we are going to develop a generalization of the ABR theory, taking into account the influence of a finite ion temperature value

Evolution of transverse instability in a hollow cylindrical weakly-ionized plasma column

International Nuclear Information System (INIS)

Kuedyan, H.M.

1978-01-01

Having observed formation of plasma striations in an Electron Cyclotron Resonance Heating (ECRH) device, we have studied the conditions under which the hollow cylindrical plasma columns would develop into striations. We first present the observed conditions of the hollow cylindrical plasma which would develop into plasma striations, the measured characteristics of the transverse oscillations and a simple small signal model for a transverse instability in a weakly-ionized hollow cylindrical plasma. This linearized model, which assumes flowing cold ion fluid (T/sub i/ approximately < 0.1 eV) in warm electron fluid (T/sub e/ approximately 1 eV) and background neutrals, reveals a transverse flute-type electrostatic instability whose characteristics are in qualitative and quantitative agreement with the measured values of the oscillations in our experiment

Assessment of Metaborate Fusion for the Rapid Dissolution of Solid Samples: Suitability with the Northstar ARSIIe

Science.gov (United States)

2016-07-01

5 Table 3. Residual Silicates avec Flocculation in Glass Beaker or Polyethylene Cone ................ 8 Table 4...is formed. Since the concentration of silicates in soil or sediment is high (up to 70-75% in silicon dioxide ( SiO2 ) in some cases), the condensation...flux, for the fusion of acidic samples such as solids containing a significant portion of SiO2 . Conversely, lithium tetraborate, an acidic flux, will

Injection and swirl driven flowfields in solid and liquid rocket motors

Science.gov (United States)

Vyas, Anand B.

In this work, we seek approximate analytical solutions to describe the bulk flow motion in certain types of solid and liquid rocket motors. In the case of an idealized solid rocket motor, a cylindrical double base propellant grain with steady regression rate is considered. The well known inviscid profile determined by Culick is extended here to include the effects of viscosity and steady grain regression. The approximate analytical solution for the cold flow is obtained from similarity principles, perturbation methods and the method of variation of parameters. The velocity, vorticity, pressure gradient and the shear stress distributions are determined and interpreted for different rates of wall regression and injection Reynolds number. The liquid propellant rocket engine considered here is based on a novel design that gives rise to a cyclonic flow. The resulting bidirectional motion is triggered by the tangential injection of an oxidizer just upstream of the chamber nozzle. Velocity, vorticity and pressure gradient distributions are determined for the bulk gas dynamics using a non-reactive inviscid model. Viscous corrections are then incorporated to explain the formation of a forced vortex near the core. Our results compare favorably with numerical simulations and experimental measurements obtained by other researchers. They also indicate that the bidirectional vortex in a cylindrical chamber is a physical solution of the Euler equations. In closing, we investigate the possibility of multi-directional flow behavior as predicted by Euler's equation and as reported recently in laboratory experiments.

An investigation on cylindrical imploding turbulent mixing

International Nuclear Information System (INIS)

Liao Haidong; Yang Libin; Zhang Xilin; Ouyang Kai; Li Jun

2001-01-01

The interfacial instability experiments in cylindrically convergent geometry are performed by imploding jelly liner with high pressure gases; and instability growth were observed with high-speed framing camera. The relevant 2D numerical simulation programs were developed and their results are in good agreement with those of experiments

System and process for dissolution of solids

Science.gov (United States)

Liezers, Martin; Farmer, III, Orville T.

2017-10-10

A system and process are disclosed for dissolution of solids and "difficult-to-dissolve" solids. A solid sample may be ablated in an ablation device to generate nanoscale particles. Nanoparticles may then swept into a coupled plasma device operating at atmospheric pressure where the solid nanoparticles are atomized. The plasma exhaust may be delivered directly into an aqueous fluid to form a solution containing the atomized and dissolved solids. The composition of the resulting solution reflects the composition of the original solid sample.

Numerical determination of transmission probabilities in cylindrical geometry

International Nuclear Information System (INIS)

Queiroz Bogado Leite, S. de.

1989-11-01

Efficient methods for numerical calculation of transmission probabilities in cylindrical geometry are presented. Relative errors of the order of 10 -5 or smaller are obtained using analytical solutions and low order quadrature integration schemes. (author) [pt

Quasi-cylindrical wave contribution in experiments on extraordinary optical transmission.

Science.gov (United States)

van Beijnum, Frerik; Rétif, Chris; Smiet, Chris B; Liu, Haitao; Lalanne, Philippe; van Exter, Martin P

2012-12-20

A metal film perforated by a regular array of subwavelength holes shows unexpectedly large transmission at particular wavelengths, a phenomenon known as the extraordinary optical transmission (EOT) of metal hole arrays. EOT was first attributed to surface plasmon polaritons, stimulating a renewed interest in plasmonics and metallic surfaces with subwavelength features. Experiments soon revealed that the field diffracted at a hole or slit is not a surface plasmon polariton mode alone. Further theoretical analysis predicted that the extra contribution, from quasi-cylindrical waves, also affects EOT. Here we report the experimental demonstration of the relative importance of surface plasmon polaritons and quasi-cylindrical waves in EOT by considering hole arrays of different hole densities. From the measured transmission spectra, we determine microscopic scattering parameters which allow us to show that quasi-cylindrical waves affect EOT only for high densities, when the hole spacing is roughly one wavelength. Apart from providing a deeper understanding of EOT, the determination of microscopic scattering parameters from the measurement of macroscopic optical properties paves the way to novel design strategies.

Parameterized Finite Element Modeling and Buckling Analysis of Six Typical Composite Grid Cylindrical Shells

Science.gov (United States)

Lai, Changliang; Wang, Junbiao; Liu, Chuang

2014-10-01

Six typical composite grid cylindrical shells are constructed by superimposing three basic types of ribs. Then buckling behavior and structural efficiency of these shells are analyzed under axial compression, pure bending, torsion and transverse bending by finite element (FE) models. The FE models are created by a parametrical FE modeling approach that defines FE models with original natural twisted geometry and orients cross-sections of beam elements exactly. And the approach is parameterized and coded by Patran Command Language (PCL). The demonstrations of FE modeling indicate the program enables efficient generation of FE models and facilitates parametric studies and design of grid shells. Using the program, the effects of helical angles on the buckling behavior of six typical grid cylindrical shells are determined. The results of these studies indicate that the triangle grid and rotated triangle grid cylindrical shell are more efficient than others under axial compression and pure bending, whereas under torsion and transverse bending, the hexagon grid cylindrical shell is most efficient. Additionally, buckling mode shapes are compared and provide an understanding of composite grid cylindrical shells that is useful in preliminary design of such structures.

Characterization of the first core sample of neutralized current acid waste from double-shell tank 101-AZ

International Nuclear Information System (INIS)

Peterson, M.E.; Scheele, R.D.; Tingey, J.M.

1989-09-01

In FY 1989, Westinghouse Hanford Company (WHC) successfully obtained four core samples (totaling seven segments) of neutralized current acid waste (NCAW) from double-shell tanks (DSTs) 101-AZ and 102-AZ. A segment was a 19-in.-long and 1-in.-diameter cylindrical sample of waste. A core sample consisted of enough 19-in.-long segments to obtain the waste of interest. Three core samples were obtained from DST 101-AZ and one core sample from DST 102-AZ. Two DST 101-AZ core samples consisted of two segments per core, and the third core sample consisted of only one segment. The third core consisted of the solids from the bottom of the tank and was used to determine the relative abrasiveness of this NCAW. The DST 102-AZ core sample consisted of two segments. The core samples were transported to the Pacific Northwest Laboratory (PNL), where the waste was extruded from its sampler and extensively characterized. A characterization plan was followed that simulated the processing of the NCAW samples through retrieval, pretreatment and vitrification process steps. Physical, rheological, chemical and radiochemical properties were measured throughout the process steps. The characterization of the first core sample from DST 101-AZ was completed, and the results are provided in this report. The results for the other core characterizations will be reported in future reports. 3 refs., 13 figs., 10 tabs

A Physically-Based Equivalent Circuit Model for the Impedance of a LiFePO₄/Graphite 26650 Cylindrical Cell

DEFF Research Database (Denmark)

Scipioni, Roberto; Jørgensen, Peter Stanley; Graves, Christopher R.

2017-01-01

In this work an Equivalent Circuit Model (ECM) is developed and used to model impedance spectra measured on a commercial 26650 LiFePO4/Graphite cylindrical cell. The ECM is based on measurements and modeling of impedance spectra recorded separately on cathode (LiFePO4) and anode (Graphite) samples...

Interfering removal in samples with high amounts of dissolved solids for the determination of arsenic and selenium by TXRF

International Nuclear Information System (INIS)

Menegario, Amauri A.; Gomes, Ana Carla F.; Pellegrinotti, Daniel C.; Gine, Maria F.; Krug, Francisco J.; Nascimento Filho, Virgilio F.

2002-01-01

A matrix separation flow system coupled with total reflection X-ray fluorescence (TXRF) is proposed to remove Ca ++ , Mg ++ , Na + and K + major cations from samples containing high amounts of totally dissolved solids, using solid-liquid phases in flow system. This system is assembled with a 1.25 mL column of AG50W-X8 resin (in protonated form) and manual commutator, allowed the separation, addition of internal standard and subsequently a 40 μL aliquot of the eluate was deposited in the reflector support, dried in a furnace for 12 hours at 60 ± 5 deg C and analysed by TXRF. All the procedure is carried out in about 90 s and 0.5 mL of sample are required. The proposed approach was applied for determination of As and Se in plant material and sea water samples. When comparing with direct analysis (without separation), a reduction of 2 to 6 times on the limits of detection for these elements was attained. The accuracy of this methodology was satisfactory for As and Se in sea water and Se in rice certified samples. This procedure could be also used for Pb interference removal in the determination of As by X-ray fluorescence. (author)

Design algorithm for generatrix profile of cylindrical crowned rollers

Directory of Open Access Journals (Sweden)

Creţu Spiridon

2017-01-01

Full Text Available The cross-section of roller profile controls the pressure distribution in the contact area and radically affects the roller bearings basic dynamic load rating and rating lives. Today the most used roller profiles are the logarithmic profile and cylindrical-crowned (ZB profile. The logarithmic profile has a continuous evolution with no discontinuities till the intersection with the end fillet while ZB profile has two more discontinuities at the intersections points between the crowning circle and straight line generatrix. Using a semianalytical method, a numerical study has been carried out to find the optimum ZB profile for rollers incorporated in cylindrical rollers bearings. The basic reference rating life (L10_r has been used as optimization criterion.

Silica Modified with Polyaniline as a Potential Sorbent for Matrix Solid Phase Dispersion (MSPD) and Dispersive Solid Phase Extraction (d-SPE) of Plant Samples

Science.gov (United States)

Sowa, Ireneusz; Wójciak-Kosior, Magdalena; Strzemski, Maciej; Sawicki, Jan; Staniak, Michał; Dresler, Sławomir; Szwerc, Wojciech; Mołdoch, Jarosław; Latalski, Michał

2018-01-01

Polyaniline (PANI) is one of the best known conductive polymers with multiple applications. Recently, it was also used in separation techniques, mostly as a component of composites for solid-phase microextraction (SPME). In the present paper, sorbent obtained by in situ polymerization of aniline directly on silica gel particles (Si-PANI) was used for dispersive solid phase extraction (d-SPE) and matrix solid–phase extraction (MSPD). The efficiency of both techniques was evaluated with the use of high performance liquid chromatography with diode array detection (HPLC-DAD) quantitative analysis. The quality of the sorbent was verified by Raman spectroscopy and microscopy combined with automated procedure using computer image analysis. For extraction experiments, triterpenes were chosen as model compounds. The optimal conditions were as follows: protonated Si-PANI impregnated with water, 160/1 sorbent/analyte ratio, 3 min of extraction time, 4 min of desorption time and methanolic solution of ammonia for elution of analytes. The proposed procedure was successfully used for pretreatment of plant samples. PMID:29565297

Transient response of a cylindrical cavity in viscoelastic saturated porous medium

Directory of Open Access Journals (Sweden)

LIU Tao

2016-10-01

Full Text Available The study on dynamic characteristics for fluid-solid coupling system in saturated porous medium is of significant academic value and potential application foreground.In this paper,the transient response of a cylindrical cavity in infinite viscoelastic saturated porous medium with the circular lining is studied,and the corresponding results can be used in the design of foundation engineering,such as the tunnel analyses in saturated soil,the nuclear waste disposal engineering,and the exploitation and utilization of geothermal reservoirs and so on.Firstly,based on the porous media theory,the governing equations of coupled system are presented,and the corresponding boundary conditions,initial conditions as well as the joint conditions are derived.Then,the differential quadrature element method and the second-order backward difference scheme are applied to discretize the governing differential equations of the coupled system on the spatial and temporal domains,respectively.Finally,the Newton-Raphson method is adopted to solve the discretization equations with the initial conditions,the transient responses of the coupled system are analyzed,the effects of the parameters are considered,and the validity of the numerical method is verified.

Selective solid-phase extraction of Ni(II) by an ion-imprinted polymer from water samples

International Nuclear Information System (INIS)

Saraji, Mohammad; Yousefi, Hamideh

2009-01-01

A new ion-imprinted polymer (IIP) material was synthesized by copolymerization of 4-vinylpyridine as monomer, ethyleneglycoldimethacrylate as crosslinking agent and 2,2'-azobis-sobutyronitrile as initiator in the presence of Ni-dithizone complex. The IIP was used as sorbent in a solid-phase extraction column. The effects of sampling volume, elution conditions, sample pH and sample flow rate on the extraction of Ni ions form water samples were studied. The maximum adsorption capacity and the relative selectivity coefficients of imprinted polymer for Ni(II)/Co(II), Ni(II)/Cu(II) and Ni(II)/Cd(II) were calculated. Compared with non-imprinted polymer particles, the IIP had higher selectivity for Ni(II). The relative selectivity factor (α r ) values of Ni(II)/Co(II), Ni(II)/Cu(II) and Ni(II)/Cd(II) were 21.6, 54.3, and 22.7, respectively, which are greater than 1. The relative standard deviation of the five replicate determinations of Ni(II) was 3.4%. The detection limit for 150 mL of sample was 1.6 μg L -1 using flame atomic absorption spectrometry. The developed method was successfully applied to the determination of trace nickel in water samples with satisfactory results.

Solid phase extraction for sample preparation in trace analysis of ionogenic compounds by capillary isotachophoresis

International Nuclear Information System (INIS)

Hutta, M.; Kaniansky, D.; Simunicova, E.; Zelenska, V.; Madajova, V.; Siskova, A.

1992-01-01

Various sorbents recommended for solid phase extraction (SPE) in sample preparation procedures were studied for use in combination with capillary isotachophoresis (ITP). They were very efficient in achieving trace concentration levels (low ppb, i.e., low parts per 10 9 ) for different types of ITP analytes present in environmental and biological matrices. A macroporous carbon sorbent was convenient for sample preparation in ITP analysis of short chain fatty acids (C 4 -C 9 ) in drinking water. Chelating sorbents based on hydroxyalkyl methacrylate matrix with salicylate, thioglycolate and 8-hydroxyquinolinate functionalities were found to be very suitable for preconcentration of heavy metals with an inherent sample clean-up. An octadecyl-bonded silica sorbent enabled in ITP a photometric detection of γ-aminobutyrate (labeled with a 2,4,6-trinitrophenyl group) at concentrations considerably lower than required for the determination of this amino acid in cerebrospinal fluid (∼5*10 -8 mol/l). (author) 34 refs.; 3 figs.; 1 tab

Magnetic resonance imaging inside cylindrical metal containers with an eddy current self-compensated method

International Nuclear Information System (INIS)

Han, Hui; Balcom, Bruce J

2011-01-01

Magnetic resonance imaging (MRI) measurements inside cylindrical metal structures have recently been proposed and form the basis for new high-pressure MRI studies. The critical problem for MRI inside cylindrical metal structures is significant eddy currents induced by the switched magnetic field gradients, which usually corrupt spatial and motion encoding without appropriate correction. In this work a so-called standard SPRITE (single point ramped imaging with T 1 enhancement) technique is applied for imaging inside cylindrical metal structures. We show that the standard SPRITE technique is fundamentally immune to large-scale eddy current effects and yields artifact-free high-quality images with no eddy current correction required. Standard SPRITE image acquisition avoids the complications involved in the measurement and compensation of eddy current effects for MRI with cylindrical metal structures. This work is a substantial advance toward the extension of MRI to new challenging systems, which are of practical importance

Hexagonal boron nitride nanosheets as adsorbents for solid-phase extraction of polychlorinated biphenyls from water samples

Energy Technology Data Exchange (ETDEWEB)

Jia, Shiliang; Wang, Zhenhua; Ding, Ning [Key Laboratory for Applied Technology of Sophisticated Analytical Instruments, Shandong Academy of Sciences, Jinan, Shandong (China); Elaine Wong, Y.-L. [Department of Chemistry, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Chen, Xiangfeng, E-mail: xiangfchensdas@163.com [Key Laboratory for Applied Technology of Sophisticated Analytical Instruments, Shandong Academy of Sciences, Jinan, Shandong (China); Department of Chemistry, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Qiu, Guangyu [Department of Physics and Materials Science, City University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong); Dominic Chan, T.-W., E-mail: twdchan@cuhk.edu.hk [Department of Chemistry, The Chinese University of Hong Kong, Hong Kong Special Administrative Region (Hong Kong)

2016-09-14

The adsorptive potential of hexagonal boron nitride nanosheets (h-BNNSs) for solid-phase extraction (SPE) of pollutants was investigated for the first time. Seven indicators of polychlorinated biphenyls (PCBs) were selected as target analytes. The adsorption of PCBs on the surface of the h-BNNSs in water was simulated by the density functional theory and molecular dynamics. The simulation results indicated that the PCBs are adsorbed on the surface by π–π, hydrophobic, and electrostatic interactions. The PCBs were extracted with an h-BNNS-packed SPE cartridge, and eluted by dichloromethane. Gas chromatography–tandem mass spectrometry working in the multiple reaction monitor mode was used for the sample quantification. The effect of extraction parameters, including the flow rate, pH value, breakthrough volume, and the ionic strength, were investigated. Under the optimal working conditions, the developed method showed low limits of detection (0.24–0.50 ng L{sup −1}; signal-to-noise ratio = 3:1), low limits of quantification (0.79–1.56 ng L{sup −1}; signal-to-noise ratio = 10:1), satisfactory linearity (r > 0.99) within the concentration range of 2–1000 ng L{sup −1}, and good precision (relative standard deviation < 12%). The PCBs concentration in environmental water samples was determined by the developed method. This results demonstrate that h-BNNSs have high analytical potential in the enrichment of pollutants. - Highlights: • The hexagonal boron nitride nanosheets were synthesized. • The nanosheets were used as adsorbent for solid-phase extraction. • The h-BN demonstrates remarkable adsorption of PCBs from water samples. • The method was successfully applied in determination of PCBs in water samples.

A three-dimensional elasticity solution of functionally graded piezoelectric cylindrical panels

International Nuclear Information System (INIS)

Sedighi, M R; Shakeri, M

2009-01-01

This research presents an exact solution of finitely long, simply supported, orthotropic, functionally graded piezoelectric (FGP), cylindrical shell panels under pressure and electrostatic excitation. The FGP cylindrical panel is first divided into linearly inhomogeneous elements (LIEs). The general solution of governing partial differential equations of the LIEs is obtained by separation of variables. The highly coupled partial differential equations are reduced to ordinary differential equations with variable coefficients by means of appropriate trigonometric expansion of displacements and electric potential in circumferential and axial directions. The resulting governing ordinary differential equations are solved by the Galerkin finite element method. In this procedure the quadratic shape function is used in each element. The present method is applied to several benchmark problems. The coupled electromechanical effect on the structural behavior of functionally graded piezoelectric cylindrical shell panels is evaluated. The influence of the material property gradient index on the variables of electric and mechanical fields is studied. Finally some results are compared with published results

Simulation and Visualization of Flows Laden with Cylindrical Nanoparticles in a Mixing Layer

Directory of Open Access Journals (Sweden)

Wenqian Lin

2018-01-01

Full Text Available The motion of cylindrical particles in a mixing layer is studied using the pseudospectral method and discrete particle model. The effect of the Stokes number and particle aspect ratio on the mixing and orientation distribution of cylindrical particles is analyzed. The results show that the rollup of mixing layer drives the particles to the edge of the vortex by centrifugal force. The cylindrical particles with the small Stokes number almost follow fluid streamlines and are mixed thoroughly, while those with the large Stokes number, centrifugalized and accumulated at the edge of the vortex, are poorly mixed. The mixing degree of particles becomes worse as the particle aspect ratio increases. The cylindrical particles would change their orientation under two torques and rotate around their axis of revolution aligned to the vorticity direction when the shear rate is low, while aligning on the flow-gradient plane beyond a critical shear rate value. More particles are oriented with the flow direction, and this phenomenon becomes more obvious with the decrease of the Stokes number and particle aspect ratio.

Development of Solid Ceramic Dosimeters for the Time-Integrative Passive Sampling of Volatile Organic Compounds in Waters.

Science.gov (United States)

Bonifacio, Riza Gabriela; Nam, Go-Un; Eom, In-Yong; Hong, Yong-Seok

2017-11-07

Time-integrative passive sampling of volatile organic compounds (VOCs) in water can now be accomplished using a solid ceramic dosimeter. A nonporous ceramic, which excludes the permeation of water, allowing only gas-phase diffusion of VOCs into the resin inside the dosimeter, effectively captured the VOCs. The mass accumulation of 11 VOCs linearly increased with time over a wide range of aqueous-phase concentrations (16.9 to 1100 μg L -1 ), and the linearity was dependent upon the Henry's constant (H). The average diffusivity of the VOCs in the solid ceramic was 1.46 × 10 -10 m 2 s -1 at 25 °C, which was 4 orders of magnitude lower than that in air (8.09 × 10 -6 m 2 s -1 ). This value was 60% greater than that in the water-permeable porous ceramic (0.92 × 10 -10 m 2 s -1 ), suggesting that its mass accumulation could be more effective than that of porous ceramic dosimeters. The mass accumulation of the VOCs in the solid ceramic dosimeter increased in the presence of salt (≥0.1 M) and with increasing temperature (4 to 40 °C) but varied only slightly with dissolved organic matter concentration. The solid ceramic dosimeter was suitable for the field testing and measurement of time-weighted average concentrations of VOC-contaminated waters.

Circumferential buckling instability of a growing cylindrical tube

KAUST Repository

Moulton, D.E.; Goriely, A.

2011-01-01

A cylindrical elastic tube under uniform radial external pressure will buckle circumferentially to a non-circular cross-section at a critical pressure. The buckling represents an instability of the inner or outer edge of the tube. This is a common

A single-electron current in a cylindrical nanolayer

International Nuclear Information System (INIS)

Kazaryan, E.M.; Aghekyan, N.G.; Sarkisyan, H.A.

2012-01-01

The orbital current and the spin magnetic moment current of an electron in a cylindrical nanolayer are investigated. It is shown that under certain conditions, the main contribution to the total current is specified by the spin magnetic moment current

Preconcentration and separation of nickel, copper and cobalt using solid phase extraction and their determination in some real samples

International Nuclear Information System (INIS)

Ghaedi, M.; Ahmadi, F.; Soylak, M.

2007-01-01

A solid phase extraction method has been developed to separate and concentrate trace amounts of nickel, cobalt and copper ions from aqueous samples for the measurement by flame atomic absorption spectrometry. By the passage of aqueous samples through activated carbon modified by dithioxamide (rubeanic acid) (DTO), Ni 2+ , Cu 2+ and Co 2+ ions adsorb quantitatively. The recoveries of analytes at pH 5.5 with 500 mg solid phase were greater than 95% without interference from alkaline, earth alkaline and some metal ions. The enrichment factor was 330. The detection limits by three sigma were 0.50 μg L -1 for copper, 0.75 μg L -1 for nickel and 0.80 μg L -1 for cobalt. The loading capacity was 0.56 mg g -1 for Ni 2+ , 0.50 mg g -1 for Cu 2+ and 0.47 mg g -1 for Co 2+ . The presented procedure was applied to the determination of analytes in tap, river and sea waters, vegetable, soil and blood samples with successfully results (recoveries greater than 95%, R.S.D. lower than 2% for n = 3)

Preconcentration and separation of nickel, copper and cobalt using solid phase extraction and their determination in some real samples

Energy Technology Data Exchange (ETDEWEB)

Ghaedi, M. [Chemistry Department, University of Yasouj, Yasouj 75914-353 (Iran, Islamic Republic of)]. E-mail: m_ghaedi@mail.yu.ac.ir; Ahmadi, F. [Gachsaran Azad University, Gachsaran (Iran, Islamic Republic of); Soylak, M. [Chemistry Department, University of Erciyes, 38039 Kayseri (Turkey)

2007-08-17

A solid phase extraction method has been developed to separate and concentrate trace amounts of nickel, cobalt and copper ions from aqueous samples for the measurement by flame atomic absorption spectrometry. By the passage of aqueous samples through activated carbon modified by dithioxamide (rubeanic acid) (DTO), Ni{sup 2+}, Cu{sup 2+} and Co{sup 2+} ions adsorb quantitatively. The recoveries of analytes at pH 5.5 with 500 mg solid phase were greater than 95% without interference from alkaline, earth alkaline and some metal ions. The enrichment factor was 330. The detection limits by three sigma were 0.50 {mu}g L{sup -1} for copper, 0.75 {mu}g L{sup -1} for nickel and 0.80 {mu}g L{sup -1} for cobalt. The loading capacity was 0.56 mg g{sup -1} for Ni{sup 2+}, 0.50 mg g{sup -1} for Cu{sup 2+} and 0.47 mg g{sup -1} for Co{sup 2+}. The presented procedure was applied to the determination of analytes in tap, river and sea waters, vegetable, soil and blood samples with successfully results (recoveries greater than 95%, R.S.D. lower than 2% for n = 3)

Preconcentration and separation of nickel, copper and cobalt using solid phase extraction and their determination in some real samples.

Science.gov (United States)

Ghaedi, M; Ahmadi, F; Soylak, M

2007-08-17

A solid phase extraction method has been developed to separate and concentrate trace amounts of nickel, cobalt and copper ions from aqueous samples for the measurement by flame atomic absorption spectrometry. By the passage of aqueous samples through activated carbon modified by dithioxamide (rubeanic acid) (DTO), Ni2+, Cu2+ and Co2+ ions adsorb quantitatively. The recoveries of analytes at pH 5.5 with 500 mg solid phase were greater than 95% without interference from alkaline, earth alkaline and some metal ions. The enrichment factor was 330. The detection limits by three sigma were 0.50 microg L(-1) for copper, 0.75 microg L(-1) for nickel and 0.80 microg L(-1) for cobalt. The loading capacity was 0.56 mg g(-1) for Ni2+, 0.50 mg g(-1) for Cu2+ and 0.47 mg g(-1) for Co2+. The presented procedure was applied to the determination of analytes in tap, river and sea waters, vegetable, soil and blood samples with successfully results (recoveries greater than 95%, R.S.D. lower than 2% for n=3).

Solid-Phase Extraction Strategies to Surmount Body Fluid Sample Complexity in High-Throughput Mass Spectrometry-Based Proteomics

Science.gov (United States)

Bladergroen, Marco R.; van der Burgt, Yuri E. M.

2015-01-01

For large-scale and standardized applications in mass spectrometry- (MS-) based proteomics automation of each step is essential. Here we present high-throughput sample preparation solutions for balancing the speed of current MS-acquisitions and the time needed for analytical workup of body fluids. The discussed workflows reduce body fluid sample complexity and apply for both bottom-up proteomics experiments and top-down protein characterization approaches. Various sample preparation methods that involve solid-phase extraction (SPE) including affinity enrichment strategies have been automated. Obtained peptide and protein fractions can be mass analyzed by direct infusion into an electrospray ionization (ESI) source or by means of matrix-assisted laser desorption ionization (MALDI) without further need of time-consuming liquid chromatography (LC) separations. PMID:25692071

Full-field peak pressure prediction of shock waves from underwater explosion of cylindrical charges

NARCIS (Netherlands)

Liu, Lei; Guo, Rui; Gao, Ke; Zeng, Ming Chao

2017-01-01

Cylindrical charge is a main form in most application of explosives. By employing numerical calculation and an indirect mapping method, the relation between peak pressures from underwater explosion of cylindrical and spherical charges is investigated, and further a model to predict full-field peak

Analysis of microcontaminants in aqueous samples by fully automated on-line solid-phase extraction-gas chromatography-mass selective detection.

NARCIS (Netherlands)

Louter, A.J.H.; van Beekvelt, C.A.; Cid Montanes, P.; Slobodník, J.; Vreuls, J.J.; Brinkman, U.A.T.

1996-01-01

The trace-level analysis of unknown organic pollutants in water requires the use of fast and sensitive methods which also provide structural information. In the present study, an on-line technique was used which combines sample preparation by means of solid-phase extraction (SPE) on a small

Marine sediments monitoring studies for trace elements with the application of fast temperature programs and solid sampling high resolution continuum source atomic absorption spectrometry

Energy Technology Data Exchange (ETDEWEB)

Orani, Anna Maria; Han, Eunmi; Mandjukov, Petko; Vassileva, Emilia, E-mail: e.vasileva-veleva@iaea.org

2015-01-01

Analytical procedure for the determination of As, Cd, Cu, Ni, Co and Cr in marine sediment samples using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR CS AAS) and direct solid sample analysis has been developed. The application of fast programs in combination with direct solid sampling allows to eliminate the drying and pretreatment steps, however makes impossible the use of liquid standards for calibration. Iridium treated platforms were applied throughout the present study. Calibration technique based on the use of solid certified reference materials (marine sediments) similar to the nature of the analyzed sample and statistics of regression analysis were applied to the real sediment samples. The instrumental parameters were optimized in order to obtain reproducible and interference free analytical signals. The ISO-17025 requirements and Eurachem guidelines were followed in the validation of the proposed analytical procedure. Accordingly, blanks, selectivity, calibration, linearity, working range, trueness, repeatability reproducibility, limits of detection and quantification and expanded uncertainty (k = 2) for all investigated elements were assessed. Two different approaches for the estimation of measurement uncertainty were applied and obtained results compared. The major contributors to the combined uncertainty of the analyte mass fraction were found to be the homogeneity of the samples and the microbalance precision. The influence of sample particle sizes on the total combined uncertainty was also evaluated. Traceability to SI system of units of the obtained by the proposed analytical procedure results was demonstrated. Additionally, validation of the methodology developed was effectuated by the comparison of the obtained results with independent method e.g. ICP-MS with external calibration. The use of solid sampling HR CS AAS for the determination of trace elements in marine sediment matrix gives significant advantages

Preliminary evaluation of new polymer matrix for solid-phase extraction of nonylphenol from water samples.

Science.gov (United States)

Guerreiro, António; Soares, Ana; Piletska, Elena; Mattiasson, Bo; Piletsky, Sergey

2008-03-31

Molecularly imprinted (MIP) and blank polymers with affinity for nonylphenol were designed using computational modelling. Chromatographic tests demonstrated higher affinity of imprinted polymers towards the template nonylphenol as compared with blank polymers. The performance of both polymers in solid-phase extraction was however very similar. Both blank and imprinted polymers appeared to be suitable for the removal and pre-concentration of nonylphenol from contaminated water samples with 99% efficiency of the recovery. The commercial resins PH(EC) (Biotage) and C18 (Varian) tested in the same conditions used for comparative purposes had recovery rate <84%. The polymer capacity for nonylphenol was 231 mg g(-1) for blank and 228 mg g(-1) for MIP. The synthesised materials can have significance for sample pre-concentration and environmental analysis of this class of compounds.

Modeling film uniformity and symmetry in ionized metal physical vapor deposition with cylindrical targets

International Nuclear Information System (INIS)

Lu Junqing; Yang Lin; Yoon, Jae Hong; Cho, Tong Yul; Tao Guoqing

2008-01-01

Severe asymmetry of the metal deposits on the trench sidewalls occurs near the wafer edge during low pressure ionized metal physical vapor deposition of Cu seed layer for microprocessor interconnects. To investigate this process and mitigate the asymmetry, an analytical view factor model based on the analogy between metal sputtering and diffuse thermal radiation was constructed to investigate deposition uniformity and symmetry for cylindrical target sputtering in low pressure (below 0.1 Pa) ionized Cu physical vapor deposition. The model predictions indicate that as the distance from the cylindrical target to wafer increases, the metal film thickness becomes more uniform across the wafer and the asymmetry of the metal deposits at the wafer edge increases significantly. These trends are similar to those for planar targets. To minimize the asymmetry, the height of the cylindrical target should be kept at a minimum. For cylindrical targets, the outward-facing sidewall of the trench could receive more direct Cu fluxes than the inward-facing one when the target to wafer distance is short. The predictions also indicate that increasing the diameter of the cylindrical target could significantly reduce the asymmetry in metal deposits at the wafer edge and make the film thickness more uniform across the wafer

Linear antenna of an arbitrary orientation and position in cylindric screen

International Nuclear Information System (INIS)

Prijmenko, S.D.; Papkovich, V.G.; Khizhnyak, N.A.

1991-01-01

An equation of the linear antenna in cylindric screen is formulated. Using the averaging method a solution of this equation for the antenna of arbitrary orientation which does not contact the screen walls or contacts them in one or two ends is received. The obtained asymptotic expression for stream permits to describe in a single manner the case of resonance and non-resonance scattering. These results may be applied in design of UHF and accelerating installations using cylindric screens charged with linear vibrators. 9 refs. (author)

New developed cylindrical TM010 mode EPR cavity for X-band in vivo tooth dosimetry.

Directory of Open Access Journals (Sweden)

Guo Junwang

Full Text Available EPR tooth in vivo dosimetry is an attractive approach for initial triage after unexpected nuclear events. An X-band cylindrical TM010 mode resonant cavity was developed for in vivo tooth dosimetry and used in EPR applications for the first time. The cavity had a trapezoidal measuring aperture at the exact position of the cavity's cylindrical wall where strong microwave magnetic field H1 concentrated and weak microwave electric field E1 distributed. Theoretical calculations and simulations were used to design and optimize the cavity parameters. The cavity features were evaluated by measuring DPPH sample, intact incisor samples embed in a gum model and the rhesus monkey teeth. The results showed that the cavity worked at designed frequency and had the ability to make EPR spectroscopy in relative high sensitivity. Sufficient modulation amplitude and microwave power could be applied into the aperture. Radiation induced EPR signal could be observed remarkably from 1 Gy irradiated intact incisor within only 30 seconds, which was among the best in scan time and detection limit. The in vivo spectroscopy was also realized by acquiring the radiation induced EPR signal from teeth of rhesus monkey whose teeth was irradiated by dose of 2 Gy. The results suggested that the cavity was sensitive to meet the demand to assess doses of significant level in short time. This cavity provided a very potential option for the development of X-band in vivo dosimetry.

Friction Compensation in the Upsetting of Cylindrical Test Specimens

DEFF Research Database (Denmark)

Christiansen, Peter; Martins, P. A. F.; Bay, Niels Oluf

2016-01-01

This manuscript presents a combined numerical andexperimental methodology for determining the stress-straincurve of metallic materials from the measurements of forceand displacement obtained in the axial compression of cylindrical test specimens with friction between the specimens and the platens....... The methodology is based on minimizing the errorbetween the average surface pressure obtained from the experimental measurements of the force and displacement and thatobtained from the slab method of analysis of metal plasticity.Three different friction models based on Coulomb friction, the constant friction...... model or combined friction models are utilized .Experimental results obtained from cylindrical and Rastegaev test specimens with different lubricants combined with the experimental determination of friction by means of ring compression tests allows compensating the effect of friction...

Fem Formulation of Heat Transfer in Cylindrical Porous Medium

Science.gov (United States)

Azeem; Khaleed, H. M. T.; Soudagar, Manzoor Elahi M.

2017-08-01

Heat transfer in porous medium can be derived from the fundamental laws of flow in porous region ass given by Henry Darcy. The fluid flow and energy transport inside the porous medium can be described with the help of momentum and energy equations. The heat transfer in cylindrical porous medium differs from its counterpart in radial and axial coordinates. The present work is focused to discuss the finite element formulation of heat transfer in cylindrical porous medium. The basic partial differential equations are derived using Darcy law which is the converted into a set of algebraic equations with the help of finite element method. The resulting equations are solved by matrix method for two solution variables involved in the coupled equations.

Performance of cylindrical-conical cyclones with different geometrical configurations

Directory of Open Access Journals (Sweden)

J.D.A.M. Santana

2001-09-01

Full Text Available The present work is a continuation of a study of the influence of geometric characteristics on the performance of reverse-flow cylindrical-conical cyclones. After studying the behavior of the pressure drop in previous work (Arnosti et al., 1998, here performance in terms of collection efficiency in the removal of particulate material is addressed. The independent variables considered in this study were inlet gas velocity (three velocities and the following dimensions of the cyclone: the cylindrical section (three heights and internal height of the gas exit duct (three heights. The tests were performed using an 3³ experimental design. Analysis of the results for overall efficiency was carried out using response surfaces and the statistical parameters were estimated from linear regression.

Flow-induced vibrations of circular cylindrical structures

International Nuclear Information System (INIS)

Chen, S.

1977-06-01

The problems of flow-induced vibrations of circular cylindrical structures are reviewed. First, the general method of analysis and classification of structural responses are presented. Then, the presentation is broken up along the lines with stationary fluid, parallel flow, and cross flow. Finally, design considerations and future research needs are pointed out. 234 references

Major- and minor-metal composition of three distinct solid material fractions associated with Juan de Fuca hydrothermal fluids (northeast Pacific), and calculation of dilution fluid samples

Science.gov (United States)

Hinkley, T.K.; Seeley, J.L.; Tatsumoto, M.

1988-01-01

Three distinct types of solid material are associated with each sample of the hydrothermal fluid that was collected from the vents of the Southern Juan de Fuca Ridge. The solid materials appear to be representative of deposits on ocean floors near mid-ocean ridges, and interpretation of the chemistry of the hydrothermal solutions requires understanding of them. Sr isotopic evidence indicates that at least two and probably all three of these solid materials were removed from the solution with which they are associated, by precipitation or adsorption. This occurred after the "pure" hydrothermal fluid was diluted and thoroughly mixed with ambient seawater. The three types of solid materials, are, respectively, a coarse Zn- and Fe-rich material with small amounts of Na and Ca; a finer material also rich in Zn and Fe, but with alkali and alkaline-earth metals; and a scum composed of Ba or Zn, with either considerable Fe or Si, and Sr. Mineral identification is uncertain because of uncertain anion composition. Only in the cases of Ba and Zn were metal masses greater in solid materials than in the associated fluids. For all other metals measured, masses in fluids dwarf those in solids. The fluids themselves contain greater concentrations of all metals measured, except Mg, than seawater. We discuss in detail the relative merits of two methods of determining the mixing proportions of "pure" hydrothermal solution and seawater in the fluids, one based on Sr isotopes, and another previously used method based on Mg concentrations. Comparison of solute concentrations in the several samples shows that degree of dilution of "pure" hydrothermal solutions by seawater, and amounts of original solutes that were removed from it as solid materials, are not related. There is no clear evidence that appreciable amounts of solid materials were not conserved (lost) either during or prior to sample collection. ?? 1988.

Bandgap calculation of two-dimensional mixed solid-fluid phononic crystals by Dirichlet-to-Neumann maps

International Nuclear Information System (INIS)

Li Fenglian; Wang Yuesheng; Zhang Chuanzeng

2011-01-01

A numerical method based on the Dirichlet-to-Neumann (DtN) map is presented to compute the bandgaps of two-dimensional phononic crystals, which are composed of square or triangular lattices of circular solid cylinders in a fluid matrix. The DtN map is constructed using the cylindrical wave expansion in a unit cell. A linear eigenvalue problem, which depends on the Bloch wave vector and involves relatively small matrices, is formulated. Numerical calculations are performed for typical systems with various acoustic impedance ratios of the solid inclusions and the fluid matrix. The results indicate that the DtN-map based method can provide accurate results for various systems efficiently. In particular it takes into account the fluid-solid interface conditions and the transverse wave mode in the solid component, which has been proven to be significant when the acoustic impedance of the solid inclusions is close to or smaller than that of the fluid matrix. For systems with an acoustic impedance of the inclusion much less than that of the matrix, physical flat bands appear in the band structures, which will be missed if the transverse wave mode in the solid inclusions is neglected.

Magnetic forces between arrays of cylindrical permanent magnets

DEFF Research Database (Denmark)

Vokoun, D.; Tomassetti, G.; Beleggia, Marco

2011-01-01

procedures. Here, we introduce analytical expressions for calculating the attraction force between two arrays of cylindrical permanent magnets and compare the predictions with experimental data obtained from force measurements with NdFeB magnets. We show that the difference between predicted and measured...

Preparation of rock samples for measurement of the thermal neutron macroscopic absorption cross-section

International Nuclear Information System (INIS)

Czubek, J.A.; Burda, J.; Drozdowicz, K.; Igielski, A.; Kowalik, W.; Krynicka-Drozdowicz, E.; Woznicka, U.

1986-03-01

Preparation of rock samples for the measurement of the thermal neutron macroscopic absorption cross-section in small cylindrical two-region systems by a pulsed technique is presented. Requirements which should be fulfilled during the preparation of the samples due to physical assumptions of the method are given. A cylindrical vessel is filled with crushed rock and saturated with a medium strongly absorbing thermal neutrons. Water solutions of boric acid of well-known macroscopic absorption cross-section are used. Mass contributions of the components in the sample are specified. This is necessary for the calculation of the thermal neutron macroscopic absorption cross-section of the rock matrix. The conditions necessary for assuring the required accuracy of the measurement are given and the detailed procedure of preparation of the rock sample is described. (author)

Analytical solution for the transport equation for neutral particles in cylindrical and Cartesian geometry

International Nuclear Information System (INIS)

Goncalves, Glenio Aguiar

2003-01-01

In this work, we are reported analytical solutions for the transport equation for neutral particles in cylindrical and cartesian geometry. For the cylindrical geometry, it is applied the Hankel transform of order zero in the S N approximation of the one-dimensional cylindrical transport equation, assuming azimuthal symmetry and isotropic scattering. This procedure is coined HTSN method. The anisotropic problem is handled using the decomposition method, generating a recursive approach, which the HTSN solution is used as initial condition. For cartesian geometry, the one and two dimensional transport equation is derived in the angular variable as many time as the degree of the anisotropic scattering. This procedure leads to set of integro-differential plus one differential equation that can be really solved by the variable separation method. Following this procedure, it was possible to come out with the Case solution for the one-dimensional problem. Numerical simulations are reported for the cylindrical transport problem both isotropic and anisotropic case of quadratic degree. (author)

Fluorine determination in coal using high-resolution graphite furnace molecular absorption spectrometry and direct solid sample analysis

Energy Technology Data Exchange (ETDEWEB)

Machado, Patrícia M.; Morés, Silvane; Pereira, Éderson R. [Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Welz, Bernhard, E-mail: w.bernardo@terra.com.br [Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Instituto Nacional de Ciência e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil); Carasek, Eduardo [Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Andrade, Jailson B. de [Instituto Nacional de Ciência e Tecnologia do CNPq, INCT de Energia e Ambiente, Universidade Federal da Bahia, 40170-115 Salvador, BA (Brazil)

2015-03-01

The absorption of the calcium mono-fluoride (CaF) molecule has been employed in this study for the determination of fluorine in coal using direct solid sample analysis and high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS GF MAS). The rotational line at 606.440 nm was used for measuring the molecular absorption in the gas phase. The pyrolysis and vaporization temperatures were 700 °C and 2100 °C, respectively. Different chemical modifiers have been studied, such as Pd and Ir as permanent modifiers, and Pd and the mixed Pd/Mg modifier in solution. The limit of detection and the characteristic mass were 0.3 and 0.1 ng F, respectively. One certified reference material (CRM) of coal (NIST 1635) and four CRMs with a non-certified value for F (SARM 18, SARM 20, BCR 40, BCR 180) were used to evaluate the accuracy and precision of the method, obtaining good agreement (104%) with the certified value and with the informed values (ranging from 90 to 103%). - Highlights: • High-resolution Graphite Furnace Molecular Absorption Spectrometry (HR-GF MAS) • Fluorine has been determined using HR-GF MAS of the CaF molecule. • The CaF molecule was generated in a graphite furnace at a temperature of 2100 °C • Coal samples have been analyzed using direct solid sample introduction. • Aqueous standard solutions have been used for calibration.

The magnetic properties of the hollow cylindrical ideal remanence magnet

DEFF Research Database (Denmark)

Bjørk, Rasmus

2016-01-01

We consider the magnetic properties of the hollow cylindrical ideal remanence magnet. This magnet is the cylindrical permanent magnet that generates a uniform field in the cylinder bore, using the least amount of magnetic energy to do so. The remanence distribution of this magnet is derived...... and the generated field is compared to that of a Halbach cylinder of equal dimensions. The ideal remanence magnet is shown in most cases to generate a significantly lower field than the equivalent Halbach cylinder, although the field is generated with higher efficiency. The most efficient Halbach cylinder is shown...... to generate a field exactly twice as large as the equivalent ideal remanence magnet....

Analytic descriptions of cylindrical electromagnetic waves in a nonlinear medium

Science.gov (United States)

Xiong, Hao; Si, Liu-Gang; Yang, Xiaoxue; Wu, Ying

2015-01-01

A simple but highly efficient approach for dealing with the problem of cylindrical electromagnetic waves propagation in a nonlinear medium is proposed based on an exact solution proposed recently. We derive an analytical explicit formula, which exhibiting rich interesting nonlinear effects, to describe the propagation of any amount of cylindrical electromagnetic waves in a nonlinear medium. The results obtained by using the present method are accurately concordant with the results of using traditional coupled-wave equations. As an example of application, we discuss how a third wave affects the sum- and difference-frequency generation of two waves propagation in the nonlinear medium. PMID:26073066

A cylindrical furnace for absorption spectral studies

Indian Academy of Sciences (India)

A cylindrical furnace with three heating zones, capable of providing a temperature of 1100°C, has been fabricated to enable recording of absorption spectra of high temperature species. The temperature of the furnace can be controlled to ± 1°C of the set temperature. The salient feature of this furnace is that the material ...

Calculated Absolute Detection Efficiencies of Cylindrical Nal (Tl) Scintillation Crystals for Aqueous Spherical Sources

Energy Technology Data Exchange (ETDEWEB)

Strindehag, O; Tollander, B

1968-08-15

Calculated values of the absolute total detection efficiencies of cylindrical scintillation crystals viewing spherical sources of various sizes are presented. The calculation is carried out for 2 x 2 inch and 3 x 3 inch Nal(Tl) crystals and for sources which have the radii 1/4, 1/2, 3/4 and 1 times the crystal radius. Source-detector distances of 5-20 cm and gamma energies in the range 0.1 - 5 MeV are considered. The correction factor for absorption in the sample container wall and in the detector housing is derived and calculated for a practical case.

Performance of a Permanent-Magnet Cylindrical Hall-Effect Thruster

Science.gov (United States)

Polzin, K. A.; Sooby, E. S.; Kimberlin, A. C.; Raites, Y.; Merino, E.; Fisch, N. J.

2009-01-01

The performance of a low-power cylindrical Hall thruster, which more readily lends itself to miniaturization and low-power operation than a conventional (annular) Hall thruster, was measured using a planar plasma probe and a thrust stand. The field in the cylindrical thruster was produced using permanent magnets, promising a power reduction over previous cylindrical thruster iterations that employed electromagnets to generate the required magnetic field topology. Two sets of ring-shaped permanent magnets are used, and two different field configurations can be produced by reorienting the poles of one magnet relative to the other. A plasma probe measuring ion flux in the plume is used to estimate the current utilization for the two magnetic topologies. The measurements indicate that electron transport is impeded much more effectively in one configuration, implying higher thrust efficiency. Thruster performance measurements on this configuration were obtained over a power range of 70-350 W and with the cathode orifice located at three different axial positions relative to the thruster exit plane. The thrust levels over this power range were 1.25-6.5 mN, with anode efficiencies and specific impulses spanning 4-21% and 400-1950 s, respectively. The anode efficiency of the permanent-magnet thruster compares favorable with the efficiency of the electromagnet thruster when the power consumed by the electromagnets is taken into account.

Chain-based communication in cylindrical underwater wireless sensor networks.

Science.gov (United States)

Javaid, Nadeem; Jafri, Mohsin Raza; Khan, Zahoor Ali; Alrajeh, Nabil; Imran, Muhammad; Vasilakos, Athanasios

2015-02-04

Appropriate network design is very significant for Underwater Wireless Sensor Networks (UWSNs). Application-oriented UWSNs are planned to achieve certain objectives. Therefore, there is always a demand for efficient data routing schemes, which can fulfill certain requirements of application-oriented UWSNs. These networks can be of any shape, i.e., rectangular, cylindrical or square. In this paper, we propose chain-based routing schemes for application-oriented cylindrical networks and also formulate mathematical models to find a global optimum path for data transmission. In the first scheme, we devise four interconnected chains of sensor nodes to perform data communication. In the second scheme, we propose routing scheme in which two chains of sensor nodes are interconnected, whereas in third scheme single-chain based routing is done in cylindrical networks. After finding local optimum paths in separate chains, we find global optimum paths through their interconnection. Moreover, we develop a computational model for the analysis of end-to-end delay. We compare the performance of the above three proposed schemes with that of Power Efficient Gathering System in Sensor Information Systems (PEGASIS) and Congestion adjusted PEGASIS (C-PEGASIS). Simulation results show that our proposed 4-chain based scheme performs better than the other selected schemes in terms of network lifetime, end-to-end delay, path loss, transmission loss, and packet sending rate.

Chain-Based Communication in Cylindrical Underwater Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Nadeem Javaid

2015-02-01

Full Text Available Appropriate network design is very significant for Underwater Wireless Sensor Networks (UWSNs. Application-oriented UWSNs are planned to achieve certain objectives. Therefore, there is always a demand for efficient data routing schemes, which can fulfill certain requirements of application-oriented UWSNs. These networks can be of any shape, i.e., rectangular, cylindrical or square. In this paper, we propose chain-based routing schemes for application-oriented cylindrical networks and also formulate mathematical models to find a global optimum path for data transmission. In the first scheme, we devise four interconnected chains of sensor nodes to perform data communication. In the second scheme, we propose routing scheme in which two chains of sensor nodes are interconnected, whereas in third scheme single-chain based routing is done in cylindrical networks. After finding local optimum paths in separate chains, we find global optimum paths through their interconnection. Moreover, we develop a computational model for the analysis of end-to-end delay. We compare the performance of the above three proposed schemes with that of Power Efficient Gathering System in Sensor Information Systems (PEGASIS and Congestion adjusted PEGASIS (C-PEGASIS. Simulation results show that our proposed 4-chain based scheme performs better than the other selected schemes in terms of network lifetime, end-to-end delay, path loss, transmission loss, and packet sending rate.

Study on Solid Phase Extraction and Spectrophotometric Determination of Nickel in Waters and Biological Samples

International Nuclear Information System (INIS)

Hu, Qiufen; Yang, Guangyu; Huang, Zhangjie; Yin, Jiayuan

2004-01-01

A sensitive, selective and rapid method for the determination of nickel based on the rapid reaction of nickel(II) with QADMAA and the solid phase extraction of the Ni(II)-QADMAA chelate with C 18 membrane disks has been developed. In the presence of pH 6.0 buffer solution and sodium dodecyl sulfonate (SDS) medium, QADMAA reacts with nickel to form a violet complex of a molar ratio of 1 : 2 (nickel to QADMAA). This chelate was enriched by solid phase extraction with C 18 membrane disks. An enrichment factor of 50 was obtained by elution of the chelates form the disks with the minimal amount of isopentyl alcohol. The molar absorptivity of the chelate was 1.32 x 10 5 L mol -1 cm -1 at 590 nm in the measured solution. Beer's law was obeyed in the range of 0.01-0.6 μg/mL. This method was applied to the determination of nickel in water and biological samples with good results

Solid phase assays

International Nuclear Information System (INIS)

Reese, M.G.; Johnson, L.R.; Ransom, D.K.

1980-01-01

In a solid phase assay for quantitative determination of biological and other analytes, a sample such as serum is contacted with a receptor for the analyte being assayed, the receptor being supported on a solid support. No tracer for the analyte is added to the sample before contacting with the receptor; instead the tracer is contacted with the receptor after unbound analyte has been removed from the receptor. The assay can be otherwise performed in a conventional manner but can give greater sensitivity. (author)

Comparison of 22G reverse-beveled versus standard needle for endoscopic ultrasound-guided sampling of solid pancreatic lesions

Science.gov (United States)

Alatawi, Abdullah; Beuvon, Frédéric; Grabar, Sophie; Leblanc, Sarah; Chaussade, Stanislas; Terris, Benoit; Barret, Maximilien

2015-01-01

Objectives Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) using standard needles has a high diagnostic value in the evaluation of solid pancreatic masses. Fenestrated needles have been developed to improve the quality of EUS-guided tissue sampling by providing core biopsies (FNB). Methods Patients with solid pancreatic masses of >2 cm were prospectively included in our study and randomized to receive EUS sampling, using either a standard 22G FNA or a 22G Procore® FNB needle. The main study endpoint was the number of needle passes required to obtain a diagnosis in more than 90% of cases. Results We included 100 patients (male = 63, female = 37; mean age = 68.4 years) in our study. We found that 88% of the lesions were malignant, with a mean size of 32 mm. A sample adequate for diagnosis was obtained in more than 90% of cases after the second needle pass in the FNB group, versus the third needle pass in the FNA group. Slide cellularity and presence of tissue microfragments were significantly higher in the FNB group. Sensitivity for the diagnosis of malignancy was 88.4% versus 97.8% for the EUS-FNA and EUS-FNB group, respectively, while specificity for both techniques was 100%. No complications were recorded. Conclusions Although the accuracy of both needle types for proving malignancy was similar, a lower number of passes was required with the FNB needles to achieve the same contributive sample rate as with the FNA needles. FNB also improved the histopathological quality of specimens, suggesting an overall superiority of FNB sampling. PMID:26279842

Perspectives of an acoustic–electrostatic/electrodynamic hybrid levitator for small fluid and solid samples

International Nuclear Information System (INIS)

Lierke, E G; Holitzner, L

2008-01-01

The feasibility of an acoustic–electrostatic hybrid levitator for small fluid and solid samples is evaluated. A proposed design and its theoretical assessment are based on the optional implementation of simple hardware components (ring electrodes) and standard laboratory equipment into typical commercial ultrasonic standing wave levitators. These levitators allow precise electrical charging of drops during syringe- or ink-jet-type deployment. The homogeneous electric 'Millikan field' between the grounded ultrasonic transducer and the electrically charged reflector provide an axial compensation of the sample weight in an indifferent equilibrium, which can be balanced by using commercial optical position sensors in combination with standard electronic PID position control. Radial electrostatic repulsion forces between the charged sample and concentric ring electrodes of the same polarity provide stable positioning at the centre of the levitator. The levitator can be used in a pure acoustic or electrostatic mode or in a hybrid combination of both subsystems. Analytical evaluations of the radial–axial force profiles are verified with detailed numerical finite element calculations under consideration of alternative boundary conditions. The simple hardware modification with implemented double-ring electrodes in ac/dc operation is also feasible for an electrodynamic/acoustic hybrid levitator

Elastic stability of cylindrical shells with soft elastic cores: Biomimicking natural tubular structures

Science.gov (United States)

Karam, Gebran Nizar

1994-01-01

Thin walled cylindrical shell structures are widespread in nature: examples include plant stems, porcupine quills, and hedgehog spines. All have an outer shell of almost fully dense material supported by a low density, cellular core. In nature, all are loaded in combination of axial compression and bending: failure is typically by buckling. Natural structures are often optimized. Here we have analyzed the elastic buckling of a thin cylindrical shell supported by an elastic core to show that this structural configuration achieves significant weight saving over a hollow cylinder. The results of the analysis are compared with data from an extensive experimental program on uniaxial compression and four point bending tests on silicone rubber shells with and without compliant foam cores. The analysis describes the results of the mechanical tests well. Characterization of the microstructures of several natural tubular structures with foamlike cores (plant stems, quills, and spines) revealed them to be close to the optimal configurations predicted by the analytical model. Biomimicking of natural cylindrical shell structures and evolutionary design processes may offer the potential to increase the mechanical efficiency of engineering cylindrical shells.

Bovine liver sample preparation and micro-homogeneity study for Cu and Zn determination by solid sampling electrothermal atomic absorption spectrometry

International Nuclear Information System (INIS)

Nomura, Cassiana S.; Silva, Cintia S.; Nogueira, Ana R.A.; Oliveira, Pedro V.

2005-01-01

This work describes a systematic study for the bovine liver sample preparation for Cu and Zn determination by solid sampling electrothermal atomic absorption spectrometry. The main parameters investigated were sample drying, grinding process, particle size, sample size, microsample homogeneity, and their relationship with the precision and accuracy of the method. A bovine liver sample was prepared using different drying procedures: (1) freeze drying, and (2) drying in a household microwave oven followed by drying in a stove at 60 deg. C until constant mass. Ball and cryogenic mills were used for grinding. Less sensitive wavelengths for Cu (216.5 nm) and Zn (307.6 nm), and Zeeman-based three-field background correction for Cu were used to diminish the sensitivities. The pyrolysis and atomization temperatures adopted were 1000 deg. C and 2300 deg. C for Cu, and 700 deg. C and 1700 deg. C for Zn, respectively. For both elements, it was possible to calibrate the spectrometer with aqueous solutions. The use of 250 μg of W + 200 μg of Rh as permanent chemical modifier was imperative for Zn. Under these conditions, the characteristic mass and detection limit were 1.4 ng and 1.6 ng for Cu, and 2.8 ng and 1.3 ng for Zn, respectively. The results showed good agreement (95% confidence level) for homogeneity of the entire material (> 200 mg) when the sample was dried in microwave/stove and ground in a cryogenic mill. The microsample homogeneity study showed that Zn is more dependent on the sample pretreatment than Cu. The bovine liver sample prepared in microwave/stove and ground in a cryogenic mill presented results with the lowest relative standard deviation for Cu than Zn. Good accuracy and precision were observed for bovine liver masses higher than 40 μg for Cu and 30 μg for Zn. The concentrations of Cu and Zn in the prepared bovine liver sample were 223 mg kg - 1 and 128 mg kg - 1 , respectively. The relative standard deviations were lower than 6% (n = 5). The

Frequency response analysis of cylindrical shells conveying fluid using finite element method

International Nuclear Information System (INIS)

Seo, Young Soo; Jeong, Weui Bong; Yoo, Wan Suk; Jeong, Ho Kyeong

2005-01-01

A finite element vibration analysis of thin-walled cylindrical shells conveying fluid with uniform velocity is presented. The dynamic behavior of thin-walled shell is based on the Sanders' theory and the fluid in cylindrical shell is considered as inviscid and incompressible so that it satisfies the Laplace's equation. A beam-like shell element is used to reduce the number of degree-of-freedom by restricting to the circumferential modes of cylindrical shell. An estimation of frequency response function of the pipe considering of the coupled effects of the internal fluid is presented. A dynamic coupling condition of the interface between the fluid and the structure is used. The effective thickness of fluid according to circumferential modes is also discussed. The influence of fluid velocity on the frequency response function is illustrated and discussed. The results by this method are compared with published results and those by commercial tools

Rapid determination of trace level copper in tea infusion samples by solid contact ion selective electrode

Directory of Open Access Journals (Sweden)

Aysenur Birinci

2016-07-01

Full Text Available A new solid contact copper selective electrode with a poly (vinyl chloride (PVC membrane consisting of o-xylylenebis(N,N-diisobutyldithiocarbamate as ionophore has been prepared. The main novelties of constructed ion selective electrode concept are the enhanced robustness, cheapness, and fastness due to the use of solid contacts. The electrode exhibits a rapid (< 10 seconds and near-Nernstian response to Cu2+ activity from 10−1 to 10−6 mol/L at the pH range of 4.0–6.0. No serious interference from common ions was found. The electrode characterizes by high potential stability, reproducibility, and full repeatability. The electrode was used as an indicator electrode in potentiometric titration of Cu(II ions with EDTA and for the direct assay of tea infusion samples by means of the calibration graph technique. The results compared favorably with those obtained by the atomic absorption spectroscopy (AAS.

Dynamic characteristics of a perforated cylindrical shell for flow distribution in SMART

Energy Technology Data Exchange (ETDEWEB)

Lim, Seungho; Choi, Youngin; Ha, Kyungrok [Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Park, Kyoung-Su, E-mail: pks6348@yonsei.ac.kr [Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Park, No-Cheol; Park, Young-Pil [Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Jeong, Kyeong-Hoon; Park, Jin-Seok [Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yuseong, Daejeon 305-303 (Korea, Republic of)

2011-10-15

Highlights: > A 1/12 scaled-down flow skirt is manufactured and a modal test is performed. > A finite element model predicts the added mass effect of the perforated cylindrical shell. > Modal characteristics are extracted by considering the fluid-structure interaction. - Abstract: The System-integrated Modular Advanced ReacTor (SMART) is a small nuclear reactor under development in Korea. It is equipped with a perforated cylindrical shell, which is called a flow skirt, in the lower plenum of the reactor for uniform flow distribution and to prevent inflow of debris into the core. This perforated cylindrical shell can be excited by external forces such as seismic or pump pulsation loads. The dynamic characteristics of the perforated cylindrical shell must be identified for further dynamic analysis. This research explores the modal analysis of the scaled-down flow skirt model submerged in coolant water. For the numerical simulation, finite element analysis is carried out to extract modal characteristics of the structure considering the fluid-structure interaction and we introduce the NAVMI factor for similarity analysis. In the finite element model, the whole shape of the perforated cylindrical shell is simulated instead of using the effective material properties. In addition, a 1/12 scaled-down flow skirt is manufactured, and an experiment is designed using an exciter and waterproof accelerometers for the modal test. Due to excellent agreement between the modal test results and the finite element analysis results such as natural frequencies and mode shapes, the finite element model is validated and can be used to predict the dynamic characteristics of the real flow skirt. Moreover, the natural frequency of the real flow skirt can be calculated from the NAVMI factor and is in good agreement with the FEM result.

The transmission probability method in one-dimensional cylindrical geometry

International Nuclear Information System (INIS)

Rubin, I.E.

1983-01-01

The collision probability method widely used in solving the problems of neutron transpopt in a reactor cell is reliable for simple cells with small number of zones. The increase of the number of zones and also taking into account the anisotropy of scattering greatly increase the scope of calculations. In order to reduce the time of calculation the transmission probability method is suggested to be used for flux calculation in one-dimensional cylindrical geometry taking into account the scattering anisotropy. The efficiency of the suggested method is verified using the one-group calculations for cylindrical cells. The use of the transmission probability method allows to present completely angular and spatial dependences is neutrons distributions without the increase in the scope of calculations. The method is especially effective in solving the multi-group problems

A curve fitting method for extrinsic camera calibration from a single image of a cylindrical object

International Nuclear Information System (INIS)

Winkler, A W; Zagar, B G

2013-01-01

An important step in the process of optical steel coil quality assurance is to measure the proportions of width and radius of steel coils as well as the relative position and orientation of the camera. This work attempts to estimate these extrinsic parameters from single images by using the cylindrical coil itself as the calibration target. Therefore, an adaptive least-squares algorithm is applied to fit parametrized curves to the detected true coil outline in the acquisition. The employed model allows for strictly separating the intrinsic and the extrinsic parameters. Thus, the intrinsic camera parameters can be calibrated beforehand using available calibration software. Furthermore, a way to segment the true coil outline in the acquired images is motivated. The proposed optimization method yields highly accurate results and can be generalized even to measure other solids which cannot be characterized by the identification of simple geometric primitives. (paper)

A curve fitting method for extrinsic camera calibration from a single image of a cylindrical object

Science.gov (United States)

Winkler, A. W.; Zagar, B. G.

2013-08-01

An important step in the process of optical steel coil quality assurance is to measure the proportions of width and radius of steel coils as well as the relative position and orientation of the camera. This work attempts to estimate these extrinsic parameters from single images by using the cylindrical coil itself as the calibration target. Therefore, an adaptive least-squares algorithm is applied to fit parametrized curves to the detected true coil outline in the acquisition. The employed model allows for strictly separating the intrinsic and the extrinsic parameters. Thus, the intrinsic camera parameters can be calibrated beforehand using available calibration software. Furthermore, a way to segment the true coil outline in the acquired images is motivated. The proposed optimization method yields highly accurate results and can be generalized even to measure other solids which cannot be characterized by the identification of simple geometric primitives.

Silica Modified with Polyaniline as a Potential Sorbent for Matrix Solid Phase Dispersion (MSPD and Dispersive Solid Phase Extraction (d-SPE of Plant Samples

Directory of Open Access Journals (Sweden)

Ireneusz Sowa

2018-03-01

Full Text Available Polyaniline (PANI is one of the best known conductive polymers with multiple applications. Recently, it was also used in separation techniques, mostly as a component of composites for solid-phase microextraction (SPME. In the present paper, sorbent obtained by in situ polymerization of aniline directly on silica gel particles (Si-PANI was used for dispersive solid phase extraction (d-SPE and matrix solid–phase extraction (MSPD. The efficiency of both techniques was evaluated with the use of high performance liquid chromatography with diode array detection (HPLC-DAD quantitative analysis. The quality of the sorbent was verified by Raman spectroscopy and microscopy combined with automated procedure using computer image analysis. For extraction experiments, triterpenes were chosen as model compounds. The optimal conditions were as follows: protonated Si-PANI impregnated with water, 160/1 sorbent/analyte ratio, 3 min of extraction time, 4 min of desorption time and methanolic solution of ammonia for elution of analytes. The proposed procedure was successfully used for pretreatment of plant samples.

Research on soundproof properties of cylindrical shells of generalized phononic crystals

Science.gov (United States)

Liu, Ru; Shu, Haisheng; Wang, Xingguo

2017-04-01

Based on the previous studies, the concept of generalized phononic crystals (GPCs) is further introduced into the cylindrical shell structures in this paper. And a type of cylindrical shells of generalized phononic crystals (CS-GPCs) is constructed, the structural field and acoustic-structural coupled field of the composite cylindrical shells are examined respectively. For the structural field, the transfer matrix method of mechanical state vector is adopted to build the transfer matrix of radial waves propagating from inside to outside. For the acoustic-structural coupled field, the expressions of the acoustic transmission/reflection coefficients and the sound insulation of acoustic waves with the excitation of center line sound source are set up. And the acoustic transmission coefficient and the frequency response of sound insulation in this mode were numerical calculated. Furthermore, the theoretical analysis results are verified by using the method of combining the numerical calculation and finite element simulation. Finally, the effects of inner and outer fluid parameters on the transmission/reflection coefficients of CS-GPCs are analyzed in detail.

Cylindrical Field Effect Transistor: A Full Volume Inversion Device

KAUST Repository

Fahad, Hossain M.

2010-01-01

inversion in the body. However, these devices are still limited by lithographic and processing challenges making them unsuitable for commercial production. This thesis explores a unique device structure called the CFET (Cylindrical Field Effect Transistors

Improving the performance parameters of metal cylindrical grid shell ...

African Journals Online (AJOL)

Improving the performance parameters of metal cylindrical grid shell structures. ... Finite element models are designed taking into account minimization of production and ... The force factors and deformation parameters of the basic circuits of a ...

Rothe's method for parabolic equations on non-cylindrical domains

Czech Academy of Sciences Publication Activity Database

Dasht, J.; Engström, J.; Kufner, Alois; Persson, L.E.

2006-01-01

Roč. 1, č. 1 (2006), s. 59-80 ISSN 0973-2306 Institutional research plan: CEZ:AV0Z10190503 Keywords : parabolic equations * non-cylindrical domains * Rothe's method * time-discretization Subject RIV: BA - General Mathematics

STEALTH: a Lagrange explicit finite difference code for solids, structural, and thermohydraulic analysis. Volume 2: sample and verification problems. Computer code manual

International Nuclear Information System (INIS)

Hofmann, R.

1982-08-01

STEALTH sample and verification problems are presented to help users become familiar with STEALTH capabilities, input, and output. Problems are grouped into articles which are completely self-contained. The pagination in each article is A.n, where A is a unique alphabetic-character article identifier and n is a sequential page number which starts from 1 on the first page of text for each article. Articles concerning new capabilities will be added as they become available. STEALTH sample and verification calculations are divided into the following general categories: transient mechanical calculations dealing with solids; transient mechanical calculations dealing with fluids; transient thermal calculations dealing with solids; transient thermal calculations dealing with fluids; static and quasi-static calculations; and complex boundary interaction calculations

Nonlinear Dynamic Buckling of Damaged Composite Cylindrical Shells

Institute of Scientific and Technical Information of China (English)

WANG Tian-lin; TANG Wen-yong; ZHANG Sheng-kun

2007-01-01

Based on the first order shear deformation theory(FSDT), the nonlinear dynamic equations involving transverse shear deformation and initial geometric imperfections were obtained by Hamilton's philosophy. Geometric deformation of the composite cylindrical shell was treated as the initial geometric imperfection in the dynamic equations, which were solved by the semi-analytical method in this paper. Stiffness reduction was employed for the damaged sub-layer, and the equivalent stiffness matrix was obtained for the delaminated area. By circumferential Fourier series expansions for shell displacements and loads and by using Galerkin technique, the nonlinear partial differential equations were transformed to ordinary differential equations which were finally solved by the finite difference method. The buckling was judged from shell responses by B-R criteria, and critical loads were then determined. The effect of the initial geometric deformation on the dynamic response and buckling of composite cylindrical shell was also discussed, as well as the effects of concomitant delamination and sub-layer matrix damages.

Response of cylindrical steel shell under seismic loading

International Nuclear Information System (INIS)

Tariq, M.; Amin, K.M.

2003-01-01

The seismic response of a cylindrical shell is simulated using the finite element method, and by spectral analysis. For this purpose the fundamental frequency of the cylinder is first calculated and compared with a published result. The mode shapes are also calculated which are later used for spectral analysis. The boundary nodes of the shell are displaced periodically according to a predetermined function of time by employing the acceleration time history of the El Centro earthquake to simulate the seismic loading. However, to conduct spectral analysis, the displacements are first transformed from the time domain to frequency domain using the Fast Fourier transformation. This spectral data is then used to obtain the actual displacement in the first mode under the given seismic loading. The techniques employed here can be used for cylindrical shell structures like rotor of a gas centrifuge, besides other structures that are subjected to seismic loading, besides in other time dependent loading conditions, for example rocket motor vibrations. (author)

Stresses at the intersection of two cylindrical shells

International Nuclear Information System (INIS)

Xue, M.D.; Chen, W.; Hwang, K.C.

1995-01-01

The stress analysis based on the theory of a thin shell is carried out for two normally intersecting cylindrical shells with a large diameter ratio. Instead of the Donnell shallow shell equation, the modified Morley equation, which is applicable to ρ 0 (R/T) 1/2 XXXX1, is used for the analysis of the shell with cut-out. The solution in terms of displacement function for the nozzle with a non-planar end is based on the Love equation. The boundary forces and displacements at the intersection are all transformed from Gaussian coordinates (α,β) on the shell, or Gaussian coordinates (ζ,θ) on the nozzle into three-dimensional cylindrical coordinates (ρ,θ,z). Their expressions on the intersecting curve are periodic functions of θ and expanded in Fourier series. Every harmonics of Fourier coefficients of boundary forces and displacements are obtained by numerical quadrature.The results obtained are in agreement with those from the finite element method and experiments for d/D≤0.8. ((orig.))

Cylindrization of a PWR core for neutronic calculations

International Nuclear Information System (INIS)

Santos, Rubens Souza dos

2005-01-01

In this work we propose a core cylindrization, starting from a PWR core configuration, through the use of an algorithm that becomes the process automated in the program, independent of the discretization. This approach overcomes the problem stemmed from the use of the neutron transport theory on the core boundary, in addition with the singularities associated with the presence of corners on the outer fuel element core of, existents in the light water reactors (LWR). The algorithm was implemented in a computational program used to identification of the control rod drop accident in a typical PWR core. The results showed that the algorithm presented consistent results comparing with an production code, for a problem with uniform properties. In our conclusions, we suggest, for future works, for analyzing the effect on mesh sizes for the Cylindrical geometry, and to compare the transport theory calculations versus diffusion theory, for the boundary conditions with corners, for typical PWR cores. (author)

A theoretical study of cylindrical ultrasound transducers for intracavitary hyperthermia

International Nuclear Information System (INIS)

Lin, W.-L.; Fan, W.-C.; Yen, J.-Y.; Chen, Y.-Y.; Shieh, M.-J.

2000-01-01

Purpose: The purpose of this paper was to examine the heating patterns and penetration depth when a cylindrical ultrasound transducer is employed for intracavitary hyperthermia treatments. Methods and Materials: The present study employs a simulation program based on a simplified power deposition model for infinitely long cylindrical ultrasound transducers. The ultrasound power in the tissue is assumed to be exponentially attenuated according to the penetration depth of the ultrasound beam, and a uniform attenuation for the entire treatment region is also assumed. The distribution of specific absorption rate (SAR) ratio (the ratio of SAR for a point within the tissue to that for a specific point on the cavity surface) is used to determine the heating pattern for a set of given parameters. The parameters considered are the ultrasound attenuation in the tissue, the cavity size, and the transducer eccentricity. Results: Simulation results show that the ultrasound attenuation in the tissue, the cavity size, and the transducer eccentricity are the most influential parameters for the distribution of SAR ratio. A low frequency transducer located in a large cavity can produce a much better penetration. The cavity size is the major parameter affecting the penetration depth for a small cavity size, such as interstitial hyperthermia. The heating pattern can also be dramatically changed by the transducer eccentricity and radiating sector. In addition, for a finite length of cylindrical transducer, lower SAR ratio appears in the regions near the applicator's edges. Conclusion: The distribution of SAR ratio indicates the relationship between the treatable region and the parameters if an appropriate threshold of SAR ratio is taken. The findings of the present study comprehend whether or not a tumor is treatable, as well as select the optimal driving frequency, the appropriate cavity size, and the eccentricity of a cylindrical transducer for a specific treatment

Fabrication and characterization of joined silicon carbide cylindrical components for nuclear applications

Science.gov (United States)

Khalifa, H. E.; Deck, C. P.; Gutierrez, O.; Jacobsen, G. M.; Back, C. A.

2015-02-01

The use of silicon carbide (SiC) composites as structural materials in nuclear applications necessitates the development of a viable joining method. One critical application for nuclear-grade joining is the sealing of fuel within a cylindrical cladding. This paper demonstrates cylindrical joint feasibility using a low activation nuclear-grade joint material comprised entirely of β-SiC. While many papers have considered joining material, this paper takes into consideration the joint geometry and component form factor, as well as the material performance. Work focused specifically on characterizing the strength and permeability performance of joints between cylindrical SiC-SiC composites and monolithic SiC endplugs. The effects of environment and neutron irradiation were not evaluated in this study. Joint test specimens of different geometries were evaluated in their as-fabricated state, as well as after being subjected to thermal cycling and partial mechanical loading. A butted scarf geometry supplied the best combination of high strength and low permeability. A leak rate performance of 2 × 10-9 mbar l s-1 was maintained after thermal cycling and partial mechanical loading and sustained applied force of 3.4 kN, or an apparent strength of 77 MPa. This work shows that a cylindrical SiC-SiC composite tube sealed with a butted scarf endplug provides out-of-pile strength and permeability performance that meets light water reactor design requirements.

Multi-Group Reductions of LTE Air Plasma Radiative Transfer in Cylindrical Geometries

Science.gov (United States)

Scoggins, James; Magin, Thierry Edouard Bertran; Wray, Alan; Mansour, Nagi N.

2013-01-01

Air plasma radiation in Local Thermodynamic Equilibrium (LTE) within cylindrical geometries is studied with an application towards modeling the radiative transfer inside arc-constrictors, a central component of constricted-arc arc jets. A detailed database of spectral absorption coefficients for LTE air is formulated using the NEQAIR code developed at NASA Ames Research Center. The database stores calculated absorption coefficients for 1,051,755 wavelengths between 0.04 µm and 200 µm over a wide temperature (500K to 15 000K) and pressure (0.1 atm to 10.0 atm) range. The multi-group method for spectral reduction is studied by generating a range of reductions including pure binning and banding reductions from the detailed absorption coefficient database. The accuracy of each reduction is compared to line-by-line calculations for cylindrical temperature profiles resembling typical profiles found in arc-constrictors. It is found that a reduction of only 1000 groups is sufficient to accurately model the LTE air radiation over a large temperature and pressure range. In addition to the reduction comparison, the cylindrical-slab formulation is compared with the finite-volume method for the numerical integration of the radiative flux inside cylinders with varying length. It is determined that cylindrical-slabs can be used to accurately model most arc-constrictors due to their high length to radius ratios.

A sensitive method for determining total vanadium in water samples using colorimetric-solid-phase extraction-fiber optic reflectance spectroscopy

International Nuclear Information System (INIS)

Filik, Hayati; Yanaz, Zeynep

2009-01-01

A selective colorimetric-solid-phase extraction (C-SPE) method for the determination of total vanadium in water samples was developed. This method introduced a new variation of C-SPE. The colour reaction is based on the reaction of vanadium(V) ternary complex formed with 1-(2-Pyridylazo)-2-naphtol (PAN) in the presence hydrogen peroxide (H 2 O 2 ). In this technique, the target analytes in samples are extracted onto solid matrix loaded with a colorimetric reagent and then quantified directly on the adsorbent surface by using a miniature fiber optic reflectance spectrometer. The measurements were carried out at a wavelength of 589.4 nm since it yielded the largest divergence different in reflectance spectra before and after reaction with the vanadium. The overall time required for the C-SPE procedure was ∼20 min. The amount of concentrated V is then determined in a few seconds by using miniature reflectance spectrometer. At the optimal conditions, a calibration curve was constructed, revealing a linear range of 0.05-0.52 mg L -1 and a detection limit as low as 0.01 mg L -1 while the RSD lower than 2.8%. In order to verify the accuracy of the method, a certified reference water samples (TMDA) were analysed and the results obtained were in good agreement with the certified values. The proposed method was applied to the determination of vanadium in tap water, seawater samples with a recovery for the spiked samples in the range of 98-102%.

Finite element analysis of cylindrical indentation for determining plastic properties of materials in small volumes

International Nuclear Information System (INIS)

Lu, Y Charles; Kurapati, Siva N V R K; Yang Fuqian

2008-01-01

The cylindrical indentation is analysed, using the finite element method, for determining the plastic properties of elastic-plastic materials and the effect of strain hardening. The results are compared with those obtained from spherical indentation, the commonly used technique for measuring plastic properties of materials in small volumes. The analysis shows that the deformation under a cylindrical indenter quickly reaches a fully plastic state and that the size (diameter) of the plastic zone remains constant during further indentation. The indentation load is proportional to the indentation depth at large indentation depth, from which the indentation pressure P m at the onset of yielding can be readily extrapolated. The analysis of cylindrical indentation suggests that it does not need parameters such as impression radius (a) and contact stiffness (S) for determining the plastic behaviour of materials. Thus, the cylindrical indentation can suppress the uncertainties in measuring material properties

Coulomb Green's function and image potential near a cylindrical diffuse interface

Science.gov (United States)

Xue, Changfeng; Huang, Qiongwei; Deng, Shaozhong

2015-12-01

In a preceding paper [Comput. Phys. Commun. 184 (1): 51-59, 2013], we revisited the problem of calculating Coulomb Green's function and image potential near a planar diffuse interface within which the dielectric permittivity of the inhomogeneous medium changes continuously along one Cartesian direction in a transition layer between two dissimilar dielectric materials. In the present paper, we consider a cylindrical diffuse interface within which the dielectric permittivity changes continuously along the radial direction instead. First we propose a specific cylindrical diffuse interface model, termed the quasi-harmonic diffuse interface model, that can admit analytical solution for the Green's function in terms of the modified Bessel functions. Then and more importantly we develop a robust numerical method for building Green's functions for any cylindrical diffuse interface models. The main idea of the numerical method is, after dividing a diffuse interface into multiple sublayers, to approximate the dielectric permittivity profile in each one of the sublayers by one of the quasi-harmonic functional form rather than simply by a constant value as one would normally do. Next we describe how to efficiently compute well-behaved ratios, products, and logarithmic derivatives of the modified Bessel functions so as to avoid direct evaluations of individual modified Bessel functions in our formulations. Finally we conduct numerical experiments to show the effectiveness of the quasi-harmonic diffuse interface model in overcoming the divergence of the image potential, to validate the numerical method in terms of its accuracy and convergence, and to demonstrate its capability for computing Green's functions for any cylindrical diffuse interface models.

Fluid free surface effect on the vibration analysis of cylindrical shells

International Nuclear Information System (INIS)

Lakis, A.A.; Brusuc, G.; Toorani, M.

2007-01-01

The present study is to investigate the effect of free surface motion of the fluid on the dynamic behavior of the thin-walled cylindrical shells. This paper outlines a semi-analytical approach to dynamic analysis of the fluid-filled horizontal cylindrical shell taking into account the free surface motion effect. The aim of the method is to provide a general approach that can be used for both analysis and synthesis of fluid structure interaction problems in the horizontal cylindrical shells where the dynamic interaction of a flexible structure and incompressible and inviscid flow is in focus. The approach is very general and allows for dynamic analysis of both uniform and non-uniform cylindrical shell considering the fluid forces including the sloshing effect exerted on the structure. The hybrid method developed in this work is on the basis of a combination of the classical finite element approach and the thin shell theory to determine the specific displacement functions. Mass and stiffness matrices of the shell are determined by precise analytical integration. A potential function is considered to develop the dynamic pressure due to the fluid. The kinetic and potential energies are evaluated for a range of fluid height to find the influence of the fluid on the dynamic responses of the structure. The influence of the physical and geometrical parameters on the fluid-structure system has been considered in the numerical solutions. When these results are compared with corresponding results available in the literature, both theory and experiment, very good agreement is obtained. (authors)

Box-Behnken design in modeling of solid-phase tea waste extraction for the removal of uranium from water samples

Energy Technology Data Exchange (ETDEWEB)

Khajeh, Mostafa; Jahanbin, Elham; Ghaffari-Moghaddam, Mansour; Moghaddam, Zahra Safaei [Zabol Univ. (Iran, Islamic Republic of). Dept. of Chemistry; Bohlooli, Mousa [Zabol Univ. (Iran, Islamic Republic of). Dept. of Biology

2015-07-01

In this study, the solid-phase tea waste procedure was used for separation, preconcentration and determination of uranium from water samples by UV-Vis spectrophotometer. In addition, Box-Behnken experimental design was employed to investigated the influence of six variables including pH, mass of adsorbent, eluent volume, amount of 1-(2-pyridylazo)-2-naphthol (PAN); and sample and eluent flow rates on the extraction of analyte. High determination coefficient (R{sup 2}) of 0.972 and adjusted-R{sup 2} of 0.943 showed the satisfactory adjustment of the polynomial regression model. This method was used for the extraction of uranium from real water samples.

Box-Behnken design in modeling of solid-phase tea waste extraction for the removal of uranium from water samples

International Nuclear Information System (INIS)

Khajeh, Mostafa; Jahanbin, Elham; Ghaffari-Moghaddam, Mansour; Moghaddam, Zahra Safaei; Bohlooli, Mousa

2015-01-01

In this study, the solid-phase tea waste procedure was used for separation, preconcentration and determination of uranium from water samples by UV-Vis spectrophotometer. In addition, Box-Behnken experimental design was employed to investigated the influence of six variables including pH, mass of adsorbent, eluent volume, amount of 1-(2-pyridylazo)-2-naphthol (PAN); and sample and eluent flow rates on the extraction of analyte. High determination coefficient (R 2 ) of 0.972 and adjusted-R 2 of 0.943 showed the satisfactory adjustment of the polynomial regression model. This method was used for the extraction of uranium from real water samples.

Cantor-type cylindrical-coordinate method for differential equations with local fractional derivatives

International Nuclear Information System (INIS)

Yang, Xiao-Jun; Srivastava, H.M.; He, Ji-Huan; Baleanu, Dumitru

2013-01-01

In this Letter, we propose to use the Cantor-type cylindrical-coordinate method in order to investigate a family of local fractional differential operators on Cantor sets. Some testing examples are given to illustrate the capability of the proposed method for the heat-conduction equation on a Cantor set and the damped wave equation in fractal strings. It is seen to be a powerful tool to convert differential equations on Cantor sets from Cantorian-coordinate systems to Cantor-type cylindrical-coordinate systems.

Dynamic shear-bending buckling experiments of cylindrical shells

International Nuclear Information System (INIS)

Hagiwara, Y.; Akiyama, H.

1995-01-01

Dynamic experimental studies of the plastic shear/bending buckling of cylindrical shells were performed. They clarified the inelastic response reduction and the seismic margin of FBR reactor vessels. The test results were incorporated into the draft of the seismic buckling design guidelines of FBR. (author). 15 refs., 3 figs

Preparation and evaluation of molecularly imprinted solid-phase micro-extraction fibers for selective extraction of phthalates in an aqueous sample

International Nuclear Information System (INIS)

He Juan; Lv Ruihe; Zhan Haijun; Wang Huizhi; Cheng Jie; Lu Kui; Wang Fengcheng

2010-01-01

A novel molecularly imprinted polymer (MIP) that was applied to a solid-phase micro-extraction (SPME) device, which could be coupled directly to gas chromatograph and mass spectrometer (GC/MS), was prepared using dibutyl phthalate (DBP) as the template molecule. The characteristics and application of this fiber were investigated. Electron microscope images indicated that the MIP-coated solid-phase micro-extraction (MI-SPME) fibers were homogeneous and porous. The extraction yield of DBP with the MI-SPME fibers was higher than that of the non-imprinted polymer (NIP)-coated SPME (NI-SPME) fibers. The MI-SPME fibers had a higher selectivity to other phthalates that had similar structures as DBP. A method was developed for the determination of phthalates using MI-SPME fibers coupled with GC/MS. The extraction conditions were optimized. Detection limits for the phthalate samples were within the range of 2.17-20.84 ng L -1 . The method was applied to five kinds of phthalates dissolved in spiked aqueous samples and resulted in recoveries of up to 94.54-105.34%, respectively. Thus, the MI-SPME fibers are suitable for the extraction of trace phthalates in complicated samples.

Design and Characterisation of Solid Electrolytes for All-Solid-State Lithium Batteries

DEFF Research Database (Denmark)

Sveinbjörnsson, Dadi Þorsteinn

The development of all-solid-state lithium batteries, in which the currently used liquid electrolytes are substituted for solid electrolyte materials, could lead to safer batteries offering higher energy densities and longer cycle lifetimes. Designing suitable solid electrolytes with sufficient...... chemical and electrochemical stability, high lithium ion conduction and negligible electronic conduction remains a challenge. The highly lithium ion conducting LiBH4-LiI solid solution is a promising solid electrolyte material. Solid solutions with a LiI content of 6.25%-50% were synthesised by planetary......-rich microstructures during ball milling is found to significantly influence the conductivity of the samples. The long-range diffusion of lithium ions was measured using quasi-elastic neutron scattering. The solid solutions are found to exhibit two-dimensional conduction in the hexagonal plane of the crystal structure...

Overflow Characteristic of Cylindrical Shape Crest Weirs Over Horizontal Bed

Directory of Open Access Journals (Sweden)

Emad4 AbdulGabbar

2013-05-01

Full Text Available The most common types of weirs are the broad-crested weir, the sharp-crested weir, the circular crested weir and the ogee crested weir. Advantages of the cylindrical weir shape include the stable overflow pattern, the ease to pass floating debris, the simplicity of design compared to ogee crest design and the associated lower costs. In present study, it was investigated the overflow characteristics of circular weirs in laboratory for various cylinder radii of three sizes (11.4, 9.0, 6.3 cm, and the models fixed on the channel bed vertically to the direction of flow. The result shows that the increase in the ratio of head to weir radius ratio (Hw/R value causes an increase in discharge coefficient (Cd value for the same height of weir. It was observed that the cylinder size (i.e. radius of cylindrical weir (R has an effect on the (Cd. The flow magnification factor (qw/qs increases with an increase in (Hw/R value and values of (qw/qs were always higher than one for all values of (Hw/R, this means that weirs of cylindrical shape performed better than those of sharp crest for any value of weir radius tested in this study.

TUNNEL POINT CLOUD FILTERING METHOD BASED ON ELLIPTIC CYLINDRICAL MODEL

Directory of Open Access Journals (Sweden)

N. Zhu

2016-06-01

Full Text Available The large number of bolts and screws that attached to the subway shield ring plates, along with the great amount of accessories of metal stents and electrical equipments mounted on the tunnel walls, make the laser point cloud data include lots of non-tunnel section points (hereinafter referred to as non-points, therefore affecting the accuracy for modeling and deformation monitoring. This paper proposed a filtering method for the point cloud based on the elliptic cylindrical model. The original laser point cloud data was firstly projected onto a horizontal plane, and a searching algorithm was given to extract the edging points of both sides, which were used further to fit the tunnel central axis. Along the axis the point cloud was segmented regionally, and then fitted as smooth elliptic cylindrical surface by means of iteration. This processing enabled the automatic filtering of those inner wall non-points. Experiments of two groups showed coincident results, that the elliptic cylindrical model based method could effectively filter out the non-points, and meet the accuracy requirements for subway deformation monitoring. The method provides a new mode for the periodic monitoring of tunnel sections all-around deformation in subways routine operation and maintenance.

Induced charge electrophoresis of a conducting cylinder in a nonconducting cylindrical pore and its micromotoring application

Science.gov (United States)

Feng, Huicheng; Wong, Teck Neng; Che, Zhizhao

2016-08-01

Induced charge electrophoresis of a conducting cylinder suspended in a nonconducting cylindrical pore is theoretically analyzed and a micromotor is proposed that utilizes the cylinder rotation. The cylinder velocities are analytically obtained in the Dirichlet and the Neumann boundary conditions of the electric field on the cylindrical pore. The results show that the cylinder not only translates but also rotates when it is eccentric with respect to the cylindrical pore. The influences of a number of parameters on the cylinder velocities are characterized in detail. The cylinder trajectories show that the cylinder approaches and becomes stationary at certain positions within the cylindrical pore. The proposed micromotor is capable of working under a heavy load with a high rotational velocity when the eccentricity is large and the applied electric field is strong.

A method of estimating hydrogen in solid and liquid samples by means of neutron thermalisation

International Nuclear Information System (INIS)

Carter, D.H.; Sanders, J.E.

1967-06-01

The count-rate of a cadmium-covered Pu239 fission chamber placed in a reactor neutron flux increases when a hydrogen-containing material is inserted due to the thermalisation of epicadmium neutrons. This effect forms the basis of a non-destructive method of estimating hydrogen in solid or liquid samples, and trial experiments to demonstrate the principles have been made. The sensitivity is such that hydrogen down to 10 p.p.m. in a typical metal should be detected. A useful feature of the method is its very low response to elements other than hydrogen. (author)

Ultrahigh-sensitive detection of molecules produced in catalytic reactions by uni-atomic-composition bi-element clusters supported on solid substrate

International Nuclear Information System (INIS)

Yasumatsu, H; Fukui, N

2013-01-01

An apparatus has been developed for measuring catalytic activities of uni-atomic-composition bi-element clusters supported on a solid substrate. The cluster sample is prepared by irradiating a cluster-ion beam having the uni-atomic composition onto the substrate on a soft-landing condition in an ultra-high vacuum. The catalytic activity is measured by temperature-programmed desorption (TPD) mass analysis. Molecules at a density as low as 3 cm −3 have been detected with an ultrahigh-sensitive TPD mass spectrometer consisting of a cylindrical electron gun, a quadrupole mass filter and a micro-channel-plate ion-detector. The high reproducibility has been achieved by careful calibration of the TPD mass spectrometer. As a benchmark example, thermal oxidation of CO catalysed on Pt 30 disks supported on a silicon surface was studied. The CO 2 products have been successfully observed at the Pt 30 density as low as 3 × 10 12 clusters in a circular area of 8 mm in diameter at the ramping rate of the sample temperature as low as 0.3 K s −1 .

Microporous Carbon Spheres Solid Phase Membrane Tip Extraction for the Analysis of Nitrosamines in Water Samples

International Nuclear Information System (INIS)

Mohammed Salisu Musa; Wan Aini Wan Ibrahim

2015-01-01

A simple solid phase membrane tip extraction (SPMTE) utilizing microporous carbon spheres (MCS) was developed for the analysis of nitrosamines in aqueous samples. The method termed MCS-SPMTE was optimized for various important extraction parameters namely conditioning organic solvent, extraction time, effects of salt addition and pH change, desorption time, desorption solvent and sample volume. Under the optimized conditions, the method indicated good linearity in the range of 10-100 μg/ L with coefficients of determination, r 2 ≥0.9984. The method also demonstrated good reproducibility with % RSDs values ranging from 2.2 - 8.9 (n = 3). Limit of detection (LOD) and limit of quantification (LOQ) for the method ranged from 3.2 - 4.8 μg/ L and 10.9 - 15.9 μg/L respectively. Recoveries for both tap-water and lake water samples spiked at 10 μg/L were in the range of 83.2 - 107.5 %. (author)

Halloysite nanotubes as a solid sorbent in ultrasound-assisted dispersive micro solid-phase extraction for the determination of bismuth in water samples using high-resolution continuum source graphite-furnace atomic absorption spectrometry

Science.gov (United States)

Krawczyk-Coda, Magdalena

2017-03-01

In this research, a simple, accurate, and inexpensive preconcentration procedure was developed for the determination of bismuth in water samples, using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR CS GFAAS). During the preconcentration step, halloysite nanotubes (HNTs) were used as a solid sorbent in ultrasound-assisted dispersive micro solid-phase extraction (USA DMSPE). The influence of the pH of the sample solution, amount of HNTs, and extraction time, as well as of the main parameters of HR CS GFAAS, on absorbance was investigated. The limit of detection was 0.005 μg L- 1. The preconcentration factor achieved for bismuth was 32. The relative standard deviation (RSD) was 4%. The accuracy of this method was validated by analyses of NIST SRM 1643e (Trace elements in water) and TMDA-54.5 (A high level fortified sample for trace elements) certified reference materials. The measured bismuth contents in these certified reference materials were in satisfactory agreement with the certified values according to the t-test for a 95% confidence level. The proposed method has been successfully applied to the determination of bismuth in five different real water samples (seawater, lake water, river water, stream water and rain water).

4He adsorbed in cylindrical silica nanopores: Effect of size on the single-atom mean kinetic energy

International Nuclear Information System (INIS)

Andreani, C.; Senesi, R.; Pantalei, C.

2007-01-01

This paper reports a study of the short-time dynamics of helium confined in silica nanopores (xerogel powder), with average pore diameters of 24 and 160 A. The longitudinal momentum distribution of helium adsorbed in xerogels has been determined via deep inelastic neutron scattering (DINS) measurements performed on the VESUVIO spectrometer at the ISIS spallation source. DINS measurements, in the attosecond time scale (i.e., 10 -16 -10 -15 s), were performed at a temperature of T=2.5 K and saturated vapor pressure conditions, with 95% pore volume filling. The average wave-vector transfer q was about 130 A -1 . For confined helium, significant changes in the values of the single-particle mean kinetic energies K > are found in the bulk phase. These are 32.6±8.7 K for the 24 A and 24.4±5.3 K for the 160 A pore diameters, remarkably higher than K >=16.2±0.4 K, the value of normal liquid 4 He at T=2.5 K and saturated vapor pressure conditions. The results are interpreted in terms of a model where 4 He atoms are arranged in concentric annuli along the cylindrical pore axis, with K > mainly dependent on the ratio between the atomic 'effective' diameter and the pore diameter. The number of solid layers close to pore surface is found to be strongly pore-size dependent with one single solid layer for 24 A diameter pore and three solid layers for 160 A diameter pore

Pulling cylindrical particles using a soft-nonparaxial tractor beam

DEFF Research Database (Denmark)

Novitsky, Andrey; Ding, Weiqiang; Wang, Maoyan

2017-01-01

In order to pull objects towards the light source a single tractor beam inevitably needs to be strongly nonparaxial. This stringent requirement makes such a tractor beam somewhat hypothetical. Here we reveal that the cylindrical shape of dielectric particles can effectively mitigate the nonparaxi......In order to pull objects towards the light source a single tractor beam inevitably needs to be strongly nonparaxial. This stringent requirement makes such a tractor beam somewhat hypothetical. Here we reveal that the cylindrical shape of dielectric particles can effectively mitigate...... the nonparaxiality requirements, reducing the incidence angle of the partial plane waves of the light beam down to 45 degrees and even to 30 degrees for respectively dipole and dipole-quadrupole objects. The optical pulling force attributed to the interaction of magnetic dipole and magnetic quadrupole moments...... and sorting of targeted particles....

Theory of precipitation effects on dead cylindrical fuels

Science.gov (United States)

Michael A. Fosberg

1972-01-01

Numerical and analytical solutions of the Fickian diffusion equation were used to determine the effects of precipitation on dead cylindrical forest fuels. The analytical solution provided a physical framework. The numerical solutions were then used to refine the analytical solution through a similarity argument. The theoretical solutions predicted realistic rates of...

Shaping of parabolic cylindrical membrane reflectors for the Dart Precision Test Bed

Science.gov (United States)

Morgan, R.; Agnes, Gregory S.; Dragovan, M.; Barber, D.; Marcin, M.; White, C.; Dooley, J.; Hatheway, A.

2004-01-01

The DART is a new telescope architecture consisting of a single aperture formed from two cylindrical parabolic reflectors. The system is ideally suited to using tensioned membranes for the reflective surfaces, owing to the zero Gaussian curvature of a cylindrical parabola. In this paper, we present experimental measurements for shaping the membranes by using curved boundary elements to achieve coarse shaping, and a pair of precision rails shaped by moments and forces at the ends, and lightly pushed into the surface, to provide fine shape control.

Determination of volatile organic hydrocarbons in water samples by solid-phase dynamic extraction

Energy Technology Data Exchange (ETDEWEB)

Jochmann, Maik A.; Schmidt, Torsten C. [Eberhard-Karls-Universitaet Tuebingen, Center for Applied Geoscience (ZAG), Tuebingen (Germany); Chair of Instrumental Analysis, University Duisburg-Essen, Duisburg (Germany); Yuan, Xue [Eberhard-Karls-Universitaet Tuebingen, Center for Applied Geoscience (ZAG), Tuebingen (Germany)

2007-03-15

In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography-mass spectrometry (HS-SPDE-GC/MS) for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated. As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-{mu}m film thickness and 56-mm film length) and were analyzed by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out, extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude. Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally, the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and aromatic hydrocarbons. (orig.)

Determination of volatile organic hydrocarbons in water samples by solid-phase dynamic extraction.

Science.gov (United States)

Jochmann, Maik A; Yuan, Xue; Schmidt, Torsten C

2007-03-01

In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography-mass spectrometry (HS-SPDE-GC/MS) for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated. As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-microm film thickness and 56-mm film length) and were analyzed by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out, extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude. Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally, the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and aromatic hydrocarbons.

Sampling and analytical procedures for the determination of VOCs released into air from natural and anthropogenic sources: A comparison between SPME (Solid Phase Micro Extraction) and ST (Solid Trap) methods

International Nuclear Information System (INIS)

Tassi, F.; Capecchiacci, F.; Buccianti, A.; Vaselli, O.

2012-01-01

In the present study, two sampling and analytical methods for VOC determination in fumarolic exhalations related to hydrothermal-magmatic reservoirs in volcanic and geothermal areas and biogas released from waste landfills were compared: (a) Solid Traps (STs), consisting of three phase (Carboxen B, Carboxen C and Carbosieve S111) absorbent stainless steel tubes and (b) Solid Phase Micro Extraction (SPME) fibers, composed of DiVinylBenzene (DVB), Carboxen and PolyDimethylSiloxane. These techniques were applied to pre-concentrate VOCs discharged from: (i) low-to-high temperature fumaroles collected at Vulcano Island, Phlegrean Fields (Italy), and Nisyros Island (Greece), (ii) recovery wells in a solid waste disposal site located near Florence (Italy). A glass condensing system cooled with water was used to collect the dry fraction of the fumarolic gases, in order to allow more efficient VOC absorption avoiding any interference by water vapor and acidic gases, such as SO 2 , H 2 S, HF and HCl, typically present at relatively high concentrations in these fluids. Up to 37 organic species, in the range of 40–400 m/z, were determined by coupling gas chromatography to mass spectrometry (GC–MS). This study shows that the VOC compositions of fumaroles and biogas determined via SPME and ST are largely consistent and can be applied to the analysis of VOCs in gases released from different natural and anthropogenic environments. The SPME method is rapid and simple and more appropriate for volcanic and geothermal emissions, where VOCs are present at relatively high concentrations and prolonged gas sampling may be hazardous for the operator. The ST method, allowing the collection of large quantities of sample, is to be preferred to analyze the VOC composition of fluids from diffuse emissions and air, where these compounds are present at relatively low concentrations.

Exact relativistic cylindrical solution of disordered radiation

International Nuclear Information System (INIS)

Fonseca Teixeira, A.F. da; Wolk, I.; Som, M.M.

1976-05-01

A source free disordered distribution of electromagnetic radiation is considered in Einstein' theory, and a time independent exact solution with cylindrical symmetry is obtained. The gravitation and pressure effects of the radiation alone are sufficient to give the distribution an equilibrium. A finite maximum concentration is found on the axis of symmetry, and decreases monotonically to zero outwards. Timelike and null geodesics are discussed

Assessment of statistical uncertainty in the quantitative analysis of solid samples in motion using laser-induced breakdown spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Cabalin, L.M.; Gonzalez, A. [Department of Analytical Chemistry, University of Malaga, E-29071 Malaga (Spain); Ruiz, J. [Department of Applied Physics I, University of Malaga, E-29071 Malaga (Spain); Laserna, J.J., E-mail: laserna@uma.e [Department of Analytical Chemistry, University of Malaga, E-29071 Malaga (Spain)

2010-08-15

Statistical uncertainty in the quantitative analysis of solid samples in motion by laser-induced breakdown spectroscopy (LIBS) has been assessed. For this purpose, a LIBS demonstrator was designed and constructed in our laboratory. The LIBS system consisted of a laboratory-scale conveyor belt, a compact optical module and a Nd:YAG laser operating at 532 nm. The speed of the conveyor belt was variable and could be adjusted up to a maximum speed of 2 m s{sup -1}. Statistical uncertainty in the analytical measurements was estimated in terms of precision (reproducibility and repeatability) and accuracy. The results obtained by LIBS on shredded scrap samples under real conditions have demonstrated that the analytical precision and accuracy of LIBS is dependent on the sample geometry, position on the conveyor belt and surface cleanliness. Flat, relatively clean scrap samples exhibited acceptable reproducibility and repeatability; by contrast, samples with an irregular shape or a dirty surface exhibited a poor relative standard deviation.

Assessment of statistical uncertainty in the quantitative analysis of solid samples in motion using laser-induced breakdown spectroscopy

Science.gov (United States)

Cabalín, L. M.; González, A.; Ruiz, J.; Laserna, J. J.

2010-08-01

Statistical uncertainty in the quantitative analysis of solid samples in motion by laser-induced breakdown spectroscopy (LIBS) has been assessed. For this purpose, a LIBS demonstrator was designed and constructed in our laboratory. The LIBS system consisted of a laboratory-scale conveyor belt, a compact optical module and a Nd:YAG laser operating at 532 nm. The speed of the conveyor belt was variable and could be adjusted up to a maximum speed of 2 m s - 1 . Statistical uncertainty in the analytical measurements was estimated in terms of precision (reproducibility and repeatability) and accuracy. The results obtained by LIBS on shredded scrap samples under real conditions have demonstrated that the analytical precision and accuracy of LIBS is dependent on the sample geometry, position on the conveyor belt and surface cleanliness. Flat, relatively clean scrap samples exhibited acceptable reproducibility and repeatability; by contrast, samples with an irregular shape or a dirty surface exhibited a poor relative standard deviation.

Assessment of statistical uncertainty in the quantitative analysis of solid samples in motion using laser-induced breakdown spectroscopy

International Nuclear Information System (INIS)

Cabalin, L.M.; Gonzalez, A.; Ruiz, J.; Laserna, J.J.

2010-01-01

Statistical uncertainty in the quantitative analysis of solid samples in motion by laser-induced breakdown spectroscopy (LIBS) has been assessed. For this purpose, a LIBS demonstrator was designed and constructed in our laboratory. The LIBS system consisted of a laboratory-scale conveyor belt, a compact optical module and a Nd:YAG laser operating at 532 nm. The speed of the conveyor belt was variable and could be adjusted up to a maximum speed of 2 m s -1 . Statistical uncertainty in the analytical measurements was estimated in terms of precision (reproducibility and repeatability) and accuracy. The results obtained by LIBS on shredded scrap samples under real conditions have demonstrated that the analytical precision and accuracy of LIBS is dependent on the sample geometry, position on the conveyor belt and surface cleanliness. Flat, relatively clean scrap samples exhibited acceptable reproducibility and repeatability; by contrast, samples with an irregular shape or a dirty surface exhibited a poor relative standard deviation.

Numerical Research on Flow Characteristics around a Hydraulic Turbine Runner at Small Opening of Cylindrical Valve

Directory of Open Access Journals (Sweden)

Zhenwei Mo

2016-01-01

Full Text Available We use the continuity equation and the Reynolds averaged Navier-Stokes equations to study the flow-pattern characteristics around a turbine runner for the small-opening cylindrical valve of a hydraulic turbine. For closure, we adopt the renormalization-group k-ε two-equation turbulence model and use the computational fluid dynamics (CFD software FLUENT to numerically simulate the three-dimensional unsteady turbulent flow through the entire passage of the hydraulic turbine. The results show that a low-pressure zone develops around the runner blades when the cylindrical valve is closed in a small opening; cavitation occurs at the blades, and a vortex appears at the outlet of the runner. As the cylindrical valve is gradually closed, the flow velocity over the runner area increases, and the pressure gradient becomes more significant as the discharge decreases. In addition, the fluid flow velocity is relatively high between the lower end of the cylindrical valve and the base, so that a high-velocity jet is easily induced. The calculation and analysis provide a theoretical basis for improving the performance of cylindrical-valve operating systems.

Secondary extinction in cylindrical and spherical crystals for X-ray and neutron diffraction

International Nuclear Information System (INIS)

Hu Huachen; Li Zhaohuan; Yang Bin; Shen Caiwan

2001-01-01

The distribution of the reflection power ratio for a neutron or x-ray diffracted from a cylindrical crystal immersed in an homogenous incident beam is obtained by the numerical solution of the transfer equations for the first time. The profile well reflects all the physical properties of the absorption and extinction behaviour in the crystals. A systematic investigation of the secondary extinction for cylindrical and spherical crystals was carried out based on these results

Technique for fabrication of ultrathin foils in cylindrical geometry for liner-plasma implosion experiments with sub-megaampere currents

Science.gov (United States)

Yager-Elorriaga, D. A.; Steiner, A. M.; Patel, S. G.; Jordan, N. M.; Lau, Y. Y.; Gilgenbach, R. M.

2015-11-01

In this work, we describe a technique for fabricating ultrathin foils in cylindrical geometry for liner-plasma implosion experiments using sub-MA currents. Liners are formed by wrapping a 400 nm, rectangular strip of aluminum foil around a dumbbell-shaped support structure with a non-conducting center rod, so that the liner dimensions are 1 cm in height, 6.55 mm in diameter, and 400 nm in thickness. The liner-plasmas are imploded by discharging ˜600 kA with ˜200 ns rise time using a 1 MA linear transformer driver, and the resulting implosions are imaged four times per shot using laser-shadowgraphy at 532 nm. This technique enables the study of plasma implosion physics, including the magneto Rayleigh-Taylor, sausage, and kink instabilities on initially solid, imploding metallic liners with university-scale pulsed power machines.

On two possible mechanisms of metallic island remotion from solid surface at heavy multicharged ion irradiation

International Nuclear Information System (INIS)

Vorob'eva, I.V.; Geguzin, Ya.E.; Monastyrenko, V.E.

1986-01-01

Two mechanisms of energy transfer from a moving ion to a metallic island film on a solid surface are described. A particular case when the energy transfer quantity is enough to remove an island from the solid surface breaking adhesion bond is considered. One mechanism is 'shaking off', another one is a 'jumping up' mechanism. The essence of the first mechanism is that an ion bombarding the surface excites a cylindrical shock wave with a front that can 'shake off' islands from the solid surface along the ion trajectory when it reaches the surface. An island is heated in pulsed mode, and during thermal expansion it should push off the substrate, and so it jumps up. The pure case of such mechanism is observed when an ion transverses an island and transfers energy to the latter one that is defined by the quantity of ion energy losses in the island

[Determination of fatty acid esters of chloropropanediols in diet samples by gas chromatography-mass spectrometry coupled with solid-supported liquid-liquid extraction].

Science.gov (United States)

Gao, Jie; Liu, Qing; Han, Feng; Miao, Hong; Zhao, Yunfeng; Wu, Yongning

2014-05-01

To establish a method for the determination of fatty acid esters of 3-monochloropropane-1, 2-diol (3-MCPD) and 2-monochloropropane-1, 3-diol (2-MCPD) in diet samples by gas chromatography-mass spectrometry (GC-MS) with solid-supported liquid-liquid extraction (SLE). Diet samples were ultrasonically extracted by hexane, followed by ester cleavage reaction with sodium methylate in methanol, and then purified by solid-supported liquid-liquid extraction. (SLE) using diatomaceous earth as the sorbent. After derivatization with heptafluorobutyrylimidazole, the analytes were detected by GC-MS and quantified by the deuterated internal standards. The limits of detection (LODs) of 3-MCPD esters and 2-MCPD esters in different diet samples were 0.002 - 0.005 mg/kg and 0.002 - 0.006 mg/kg. The average recoveries of 3-MCPD esters and 2-MCPD esters at the spiking levels of 0.05 and 0.1 mg/kg in the diet samples were in the range of 65.9% - 104.2% and 75.4% - 118.0%, respectively, with the relative standard deviations in the range of 2.2% - 14.2% and 0.8% - .13.9%. The method is simple, accurate and rugged for the determination of fatty acid esters of 3-MCPD and 2-MCPD in diet samples.

Modeling dose-rate on/over the surface of cylindrical radio-models using Monte Carlo methods

International Nuclear Information System (INIS)

Xiao Xuefu; Ma Guoxue; Wen Fuping; Wang Zhongqi; Wang Chaohui; Zhang Jiyun; Huang Qingbo; Zhang Jiaqiu; Wang Xinxing; Wang Jun

2004-01-01

Objective: To determine the dose-rates on/over the surface of 10 cylindrical radio-models, which belong to the Metrology Station of Radio-Geological Survey of CNNC. Methods: The dose-rates on/over the surface of 10 cylindrical radio-models were modeled using the famous Monte Carlo code-MCNP. The dose-rates on/over the surface of 10 cylindrical radio-models were measured by a high gas pressurized ionization chamber dose-rate meter, respectively. The values of dose-rate modeled using MCNP code were compared with those obtained by authors in the present experimental measurement, and with those obtained by other workers previously. Some factors causing the discrepancy between the data obtained by authors using MCNP code and the data obtained using other methods are discussed in this paper. Results: The data of dose-rates on/over the surface of 10 cylindrical radio-models, obtained using MCNP code, were in good agreement with those obtained by other workers using the theoretical method. They were within the discrepancy of ±5% in general, and the maximum discrepancy was less than 10%. Conclusions: As if each factor needed for the Monte Carlo code is correct, the dose-rates on/over the surface of cylindrical radio-models modeled using the Monte Carlo code are correct with an uncertainty of 3%

Positive column of the discharge in a cylindrical shell

International Nuclear Information System (INIS)

Uehara, M.; Maciel, H.S.

1991-01-01

A Schottky type theoretical model is presented for the positive column of a discharge on a cylindric shell contained gas, with the discharge current flowing in the longitudinal direction. Some analytical results and the conclusion are presented. (L.C.J.A.). 5 refs

Cylindrical Taylor states conserving total absolute magnetic helicity

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Low, B. C.; Fang, F.

2014-09-01

The Taylor state of a three-dimensional (3D) magnetic field in an upright cylindrical domain V is derived from first principles as an extremum of the total magnetic energy subject to a conserved, total absolute helicity Habs. This new helicity [Low, Phys. Plasmas 18, 052901 (2011)] is distinct from the well known classical total helicity and relative total helicity in common use to describe wholly-contained and anchored fields, respectively. A given field B, tangential along the cylindrical side of V, may be represented as a unique linear superposition of two flux systems, an axially extended system along V and a strictly transverse system carrying information on field-circulation. This specialized Chandrasekhar-Kendall representation defines Habs and permits a neat formulation of the boundary-value problem (BVP) for the Taylor state as a constant-α force-free field, treating 3D wholly-contained and anchored fields on the same conceptual basis. In this formulation, the governing equation is a scalar integro-partial differential equation (PDE). A family of series solutions for an anchored field is presented as an illustration of this class of BVPs. Past treatments of the constant-α field in 3D cylindrical geometry are based on a scalar Helmholtz PDE as the governing equation, with issues of inconsistency in the published field solutions discussed over time in the journal literature. The constant-α force-free equation reduces to a scalar Helmholtz PDE only as special cases of the 3D integro-PDE derived here. In contrast, the constant-α force-free equation and the scalar Helmholtz PDE are absolutely equivalent in the spherical domain as discussed in Appendix. This theoretical study is motivated by the investigation of the Sun's corona but the results are also relevant to laboratory plasmas.

Static Solutions of Einstein's Equations with Cylindrical Symmetry

Science.gov (United States)

Trendafilova, C. S.; Fulling, S. A.

2011-01-01

In analogy with the standard derivation of the Schwarzschild solution, we find all static, cylindrically symmetric solutions of the Einstein field equations for vacuum. These include not only the well-known cone solution, which is locally flat, but others in which the metric coefficients are powers of the radial coordinate and the spacetime is…

Microinstabilities in a radially contracting inhomogeneous cylindrical plasma slab

International Nuclear Information System (INIS)

Deutsch, R.; Kaeppeler, H.J.

1980-07-01

In order to study the development of microinstabilities in a collapsing cylindrical plasma sheath, corresponding to the situations in a z-pinch or a plasma focus, the dispersion relation for electromagnetic perturbations is derived with the aid of a newly established slab-model for an inhomogeneous, radially contracting plasma. In contrast to previously used slab-models, the orientation of the electric field is in direction of the cylinder axis and the azimuthal magnetic field is induced by the current flowing through the cylindrical plasma slab. The Vlasov equation is used together with the Krook collision term in order to include the influence of collisions. The results of this theory presented in this report will be used to calculate the growth of drift instabilities in the compression phase of a plasma focus, and shall serve as a basis for further development of a more general dispersion relation including runaway-effects. (orig.)

Enhanced Performance of Cylindrical Hall Thrusters

International Nuclear Information System (INIS)

Raitses, Y.; Smirnov, A.; Fisch, N.J.

2007-01-01

The cylindrical thruster differs significantly in its underlying physical mechanisms from the conventional annular Hall thruster. It features high ionization efficiency, quiet operation, ion acceleration in a large volume-to-surface ratio channel, and performance comparable with the state-of-the-art conventional Hall thrusters. Very significant plume narrowing, accompanied by the increase of the energetic ion fraction and improvement of ion focusing, led to 50-60% increase of the thruster anode efficiency. These improvements were achieved by overrunning the discharge current in the magnetized thruster plasma

Simultaneous Determination of TetracyclinesResidues in Bovine Milk Samples by Solid Phase Extraction and HPLC-FL Method

Directory of Open Access Journals (Sweden)

Mehra Mesgari Abbasi

2011-06-01

Full Text Available Introduction:Tetracyclines (TCs are widely used in animal husbandry and their residues in milk may resultinharmful effects on human. The aim of this study was to investigate the presence of TCs residues in various bovine milk samples from local markets of Ardabil, Iran. Methods:One hundred and fourteen pasteurized, sterilized and raw milk samples were collected from markets of Ardabil. Tetracycline, Oxytetracycline and Chlortetracycline (TCs residues extraction carried out by Solid Phase Extraction method. Determination of TCs residues were performed by high performance liquid chromatography (HPLC method using Fluorescence detector.Results: The mean of total TCs residues in all samples (114 samples was 97.6 ±16.9ng/g and that of pasteurized, sterilized and raw milk samples were 87.1 ± 17.7, 112.0 ± 57.3 and 154.0 ± 66.3ng/g respectively. Twenty five point four percent of the all samples, and24.4%, 30% and 28.6% of the pasteurized, sterilized and raw milk samples, respectively had higher TCs residues than the recommended maximum levels (100ng/g. Conclusion:This study indicates the presence of tetracycline residues more than allowed amount. Regulatory authorities should ensure proper withdrawal period before milking the animals and definite supervisions are necessary on application of these drugs.

Escape and transmission probabilities in cylindrical geometry

International Nuclear Information System (INIS)

Bjerke, M.A.

1980-01-01

An improved technique for the generation of escape and transmission probabilities in cylindrical geometry was applied to the existing resonance cross section processing code ROLAIDS. The algorithm of Hwang and Toppel, [ANL-FRA-TM-118] (with modifications) was employed. The probabilities generated were found to be as accurate as those given by the method previously applied in ROLAIDS, while requiring much less computer core storage and CPU time

Transmission of infrared radiation through cylindrical waveguides

International Nuclear Information System (INIS)

Nucara, A.; Dore, P.; Calvani, P.; Cannavo', D.; Marcelli, A.

1998-01-01

Measurement of the transmittance of infrared radiation (v -1 ) through cylindrical waveguides are presented and discussed. The experimental results are compared with numerical simulations, obtained through conventional ray tracing programs. Finally, it' estimated the transmittance of a waveguide in the case of an infrared synchrotron radiation source. Are applied the results to the case of the DAΦNE collider, where a synchrotron radiation beamline for the far infrared is under construction

Effective response of nonlinear cylindrical coated composites under external AC and DC electric field

International Nuclear Information System (INIS)

Yu-Yan, Shen; Xiao-Gang, Chen; Wei, Cui; Yan-Hua, Hao; Qian-Qian, Li

2009-01-01

This paper uses the perturbation method to study effective response of nonlinear cylindrical coated composites. Under the external AC and DC electric field E a (1 + sin ωt), the local potentials of composites at all harmonic frequencies are induced. An effective nonlinear response to composite is given for the cylindrical coated inclusions in the dilute limit. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Reduction of the radiating sound of a submerged finite cylindrical shell structure by active vibration control.

Science.gov (United States)

Kim, Heung Soo; Sohn, Jung Woo; Jeon, Juncheol; Choi, Seung-Bok

2013-02-06

In this work, active vibration control of an underwater cylindrical shell structure was investigated, to suppress structural vibration and structure-borne noise in water. Finite element modeling of the submerged cylindrical shell structure was developed, and experimentally evaluated. Modal reduction was conducted to obtain the reduced system equation for the active feedback control algorithm. Three Macro Fiber Composites (MFCs) were used as actuators and sensors. One MFC was used as an exciter. The optimum control algorithm was designed based on the reduced system equations. The active control performance was then evaluated using the lab scale underwater cylindrical shell structure. Structural vibration and structure-borne noise of the underwater cylindrical shell structure were reduced significantly by activating the optimal controller associated with the MFC actuators. The results provide that active vibration control of the underwater structure is a useful means to reduce structure-borne noise in water.

Reduction of the Radiating Sound of a Submerged Finite Cylindrical Shell Structure by Active Vibration Control

Directory of Open Access Journals (Sweden)

Seung-Bok Choi

2013-02-01

Full Text Available In this work, active vibration control of an underwater cylindrical shell structure was investigated, to suppress structural vibration and structure-borne noise in water. Finite element modeling of the submerged cylindrical shell structure was developed, and experimentally evaluated. Modal reduction was conducted to obtain the reduced system equation for the active feedback control algorithm. Three Macro Fiber Composites (MFCs were used as actuators and sensors. One MFC was used as an exciter. The optimum control algorithm was designed based on the reduced system equations. The active control performance was then evaluated using the lab scale underwater cylindrical shell structure. Structural vibration and structure-borne noise of the underwater cylindrical shell structure were reduced significantly by activating the optimal controller associated with the MFC actuators. The results provide that active vibration control of the underwater structure is a useful means to reduce structure-borne noise in water.

Prevalence and associations of anisometropia with spherical ametropia, cylindrical power, age, and sex in refractive surgery candidates.

Science.gov (United States)

Linke, Stephan J; Richard, Gisbert; Katz, Toam

2011-09-29

To analyze the prevalence and associations of anisometropia with spherical ametropia, astigmatism, age, and sex in a refractive surgery population. Medical records of 27,070 eyes of 13,535 refractive surgery candidates were reviewed. Anisometropia, defined as the absolute difference in mean spherical equivalent powers between right and left eyes, was analyzed for subjective (A(subj)) and cycloplegic refraction (A(cycl)). Correlations between anisometropia (>1 diopter) and spherical ametropia, cylindrical power, age, and sex, were analyzed using χ² and nonparametric Kruskal-Wallis or Mann-Whitney tests and binomial logistic regression analyses. Power vector analysis was applied for further analysis of cylindrical power. Prevalence of A(subj) was 18.5% and of A(cycl) was 19.3%. In hyperopes, logistic regression analysis revealed that only spherical refractive error (odds ratio [OR], 0.72) and age (OR, 0.97) were independently associated with anisometropia. A(subj) decreased with increasing spherical ametropia and advancing age. Cylindrical power and sex did not significantly affect A(subj). In myopes all explanatory variables (spherical power OR, 0.93; cylindrical power OR, 0.75; age OR, 1.02; sex OR, 0.8) were independently associated with anisometropia. Cylindrical power was most strongly associated with anisometropia. Advancing age and increasing spherical/cylindrical power correlated positively with increasing anisometropia in myopic subjects. Female sex was more closely associated with anisometropia. This large-scale retrospective analysis confirmed an independent association between anisometropia and both spherical ametropia and age in refractive surgery candidates. Notably, an inverse relationship between these parameters in hyperopes was observed. Cylindrical power and female sex were independently associated with anisometropia in myopes.

Fermionic vacuum polarization by a cylindrical boundary in the cosmic string spacetime

International Nuclear Information System (INIS)

Bezerra de Mello, E. R.; Bezerra, V. B.; Saharian, A. A.; Tarloyan, A. S.

2008-01-01

The vacuum expectation values of the energy-momentum tensor and the fermionic condensate are analyzed for a massive spinor field obeying the MIT bag boundary condition on a cylindrical shell in the cosmic string spacetime. Both regions inside and outside the shell are considered. By applying to the corresponding mode sums a variant of the generalized Abel-Plana formula, we explicitly extract the parts in the expectation values corresponding to the cosmic string geometry without boundaries. In this way the renormalization procedure is reduced to that for the boundary-free cosmic string spacetime. The parts induced by the cylindrical shell are presented in terms of integrals rapidly convergent for points away from the boundary. The behavior of the vacuum densities is investigated in various asymptotic regions of the parameters. In the limit of large values of the planar angle deficit, the boundary-induced expectation values are exponentially suppressed. As a special case, we discuss the fermionic vacuum densities for the cylindrical shell on the background of the Minkowski spacetime.

A calculation model for primary intensity distributions from cylindrically symmetric x-ray lenses

International Nuclear Information System (INIS)

Hristov, Dimitre; Maltz, Jonathan

2008-01-01

A calculation model for the quantitative prediction of primary intensity fluence distributions obtained by the Bragg diffraction focusing of kilovoltage radiation by cylindrical x-ray lenses is presented. The mathematical formalism describes primary intensity distributions from cylindrically-symmetric x-ray lenses, with a planar isotropic radiation source located in a plane perpendicular to the lens axis. The presence of attenuating medium inserted between the lens and the lens focus is accounted for by energy-dependent attenuation. The influence of radiation scattered within the media is ignored. Intensity patterns are modeled under the assumption that photons that are not interacting with the lens are blocked out at any point of interest. The main characteristics of the proposed calculation procedure are that (i) the application of vector formalism allows universal treatment of all cylindrical lenses without the need of explicit geometric constructs; (ii) intensity distributions resulting from x-ray diffraction are described by a 3D generalization of the mosaic spread concept; (iii) the calculation model can be immediately coupled to x-ray diffraction simulation packages such as XOP and Shadow. Numerical simulations based on this model are to facilitate the design of focused orthovoltage treatment (FOT) systems employing cylindrical x-ray lenses, by providing insight about the influence of the x-ray source and lens parameters on quantities of dosimetric interest to radiation therapy

Coupled dilaton and electromagnetic field in cylindrically symmetric ...

Indian Academy of Sciences (India)

An exact solution is obtained for coupled dilaton and electromagnetic field in a cylindrically symmetric spacetime where an axial magnetic field as well as a radial electric field both are present. Depending on the choice of the arbitrary constants our solution reduces either to dilatonic gravity with pure electric field or to that ...

Simulation of cylindrical Pierce diodes with radial flow

International Nuclear Information System (INIS)

Alves, M.V.; Gnavi, G.; Gratton, F.T.; Buenos Aires Univ.

1996-01-01

In this paper we study the electron instability and the non linear behaviour of cylindrical Pierce's diodes by particle simulation. We ignore here the ion contribution (ions are fixed at a 1/r density and given a very large mass) to give perspicuity to the electron dynamics, and to facilitate comparison with existing theory. (author). 8 refs., 10 figs

Measurement of cylindrical particles with phase Doppler anemometry.

Science.gov (United States)

Mignon, H; Gréhan, G; Gouesbet, G; Xu, T H; Tropea, C

1996-09-01

Light scattering from cylindrical particles has been described with geometric optics. The feasibility of determining the particle diameter with a planar phase Doppler anemometer has been examined by simulations and experiments. In particular, the influence of particle orientation on measurability and measurement accuracy has been investigated. Some recommendations for realizing a practical-measurement instrument have been presented.

WIPP Sampling and Analysis Plan for Solid Waste Management Units and Areas of Concern

International Nuclear Information System (INIS)

2000-01-01

This Sampling and Analysis Plan (SAP) has been prepared to fulfill requirements of Module VII, Section VII.M.2 and Table VII.1, requirement 4 of the Waste Isolation Pilot Plant (WIPP) Hazardous Waste Permit, NM4890139088-TSDF (the Permit); (NMED [New Mexico Environment Department], 1999a). This SAP describes the approach for investigation of the Solid Waste Management Units (SWMU) and Areas of Concern (AOC) specified in the Permit. This SAP addresses the current Permit requirements for a RCRA Facility Investigation(RFI) investigation of SWMUs and AOCs. It uses the results of previous investigations performed at WIPP and expands the investigations as required by the Permit. As an alternative to the RFI specified in Module VII of the Permit, current NMED guidance identifies an Accelerated Corrective Action Approach (ACAA) that may be used for any SWMU or AOC (NMED, 1998). This accelerated approach is used to replace the standard RFI work plan and report sequence with a more flexible decision-making approach. The ACAA process allows a facility to exit the schedule of compliance contained in the facility's Hazardous and Solid Waste Amendments (HSWA) permit module and proceed on an accelerated time frame. Thus, the ACAA process can beentered either before or after a RFI work plan. According to NMED's guidance, a facility can prepare a RFI work plan or SAP for any SWMU or AOC (NMED, 1998).

Multimode interaction in axially excited cylindrical shells

Directory of Open Access Journals (Sweden)

Silva F. M. A.

2014-01-01

Full Text Available Cylindrical shells exhibit a dense frequency spectrum, especially near the lowest frequency range. In addition, due to the circumferential symmetry, frequencies occur in pairs. So, in the vicinity of the lowest natural frequencies, several equal or nearly equal frequencies may occur, leading to a complex dynamic behavior. So, the aim of the present work is to investigate the dynamic behavior and stability of cylindrical shells under axial forcing with multiple equal or nearly equal natural frequencies. The shell is modelled using the Donnell nonlinear shallow shell theory and the discretized equations of motion are obtained by applying the Galerkin method. For this, a modal solution that takes into account the modal interaction among the relevant modes and the influence of their companion modes (modes with rotational symmetry, which satisfies the boundary and continuity conditions of the shell, is derived. Special attention is given to the 1:1:1:1 internal resonance (four interacting modes. Solving numerically the governing equations of motion and using several tools of nonlinear dynamics, a detailed parametric analysis is conducted to clarify the influence of the internal resonances on the bifurcations, stability boundaries, nonlinear vibration modes and basins of attraction of the structure.

Numerical Study on the Tensile Behavior of 3D Four Directional Cylindrical Braided Composite Shafts

Science.gov (United States)

Zhao, Guoqi; Wang, Jiayi; Hao, Wenfeng; Liu, Yinghua; Luo, Ying

2017-10-01

The tensile behavior of 3D four directional cylindrical braided composite shafts was analyzed with the numerical method. The unit cell models for the 3D four directional cylindrical braided composite shafts with various braiding angles were constructed with ABAQUS. Hashin's failure criterion was used to analyze the tensile strength and the damage evolution of the unit cells. The influence of the braiding angle on the tensile behavior of the 3D four directional cylindrical braided composite shafts was analyzed. The numerical results showed that the tensile strength along the braiding direction increased as the braiding angle decreased. These results should play an integral role in the design of braiding composites shafts.

A study of aerosol deposition by thermophoresis in cylindrical ducts