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Sample records for experimentally determined volumetric

  1. Method for Determining Volumetric Efficiency and Its Experimental Validation

    Directory of Open Access Journals (Sweden)

    Ambrozik Andrzej

    2017-12-01

    Full Text Available Modern means of transport are basically powered by piston internal combustion engines. Increasingly rigorous demands are placed on IC engines in order to minimise the detrimental impact they have on the natural environment. That stimulates the development of research on piston internal combustion engines. The research involves experimental and theoretical investigations carried out using computer technologies. While being filled, the cylinder is considered to be an open thermodynamic system, in which non-stationary processes occur. To make calculations of thermodynamic parameters of the engine operating cycle, based on the comparison of cycles, it is necessary to know the mean constant value of cylinder pressure throughout this process. Because of the character of in-cylinder pressure pattern and difficulties in pressure experimental determination, in the present paper, a novel method for the determination of this quantity was presented. In the new approach, the iteration method was used. In the method developed for determining the volumetric efficiency, the following equations were employed: the law of conservation of the amount of substance, the first law of thermodynamics for open system, dependences for changes in the cylinder volume vs. the crankshaft rotation angle, and the state equation. The results of calculations performed with this method were validated by means of experimental investigations carried out for a selected engine at the engine test bench. A satisfactory congruence of computational and experimental results as regards determining the volumetric efficiency was obtained. The method for determining the volumetric efficiency presented in the paper can be used to investigate the processes taking place in the cylinder of an IC engine.

  2. Comparison of experimental methods for determination of the volumetric mass transfer coefficient in fermentation processes

    Science.gov (United States)

    Tobajas, M.; García-Calvo, E.

    Mass transfer in bioreactors has been examined. In the present work, dynamic methods are used for the determination of KLa values for water, model media and a fermentation broth (Candida utilis) in an airlift reactor. The conventional dynamic method is applied at the end of the microbial process in order to avoid an alteration in the metabolism of the microorganisms. New dynamic methods are used to determine KLa in an airlift reactor during the microbial growth of Candida utilis on glucose. One of the methods is based on the continuous measurement of carbon dioxide production while the other method is based on the relationship between the oxygen transfer and biomass growth rates. These methods of determining KLa does not interfere with the microorganisms action. A theoretical mass transfer model has been used for KLa estimation for the systems described above. Some differences between calculated and measured values are found for fermentation processes due to the model is developed for two-phase air-water systems. Nevertheless, the average deviation between the predicted values and those obtained from the relationship between oxygen transfer and biomass production rates are lower than 25% in any case.

  3. Determination of uranium by a gravimetric-volumetric titration method

    International Nuclear Information System (INIS)

    Krtil, J.

    1998-01-01

    A volumetric-gravimetric modification of a method for the determination of uranium based on the reduction of uranium to U (IV) in a phosphoric acid medium and titration with a standard potassium dichromate solution is described. More than 99% of the stoichiometric amount of the titrating solution is weighed and the remainder is added volumetrically by using the Mettler DL 40 RC Memotitrator. Computer interconnected with analytical balances collects continually the data on the analyzed samples and evaluates the results of determination. The method allows to determine uranium in samples of uranium metal, alloys, oxides, and ammonium diuranate by using aliquot portions containing 30 - 100 mg of uranium with the error of determination, expressed as the relative standard deviation, of 0.02 - 0.05%. (author)

  4. Determination of delta ferrite volumetric fraction in austenitic stainless steel

    International Nuclear Information System (INIS)

    Almeida Macedo, W.A. de.

    1983-01-01

    Measurements of delta ferrite volumetric fraction in AISI 304 austenitic stainless steels were done by X-ray diffraction, quantitative metallography (point count) and by means of one specific commercial apparatus whose operational principle is magnetic-inductive: The Ferrite Content Meter 1053 / Institut Dr. Foerster. The results obtained were comparated with point count, the reference method. It was also investigated in these measurements the influence of the martensite induced by mechanical deformation. Determinations by X-ray diffraction, by the ratio between integrated intensities of the ferrite (211) and austenite (311) lines, are in excelent agreement with those taken by point count. One correction curve for the lectures of the commercial equipment in focus was obtained, for the range between zero and 20% of delta ferrite in 18/8 stainless steels. It is demonstrated that, depending on the employed measurement method and surface finishing of the material to be analysed, the presence of martensite produced by mechanical deformation of the austenitic matrix is one problem to be considered. (Author) [pt

  5. Determination of delta ferrite volumetric fraction in austenitic stainless steels

    International Nuclear Information System (INIS)

    Almeida Macedo, W.A. de.

    1983-01-01

    Measurements of delta ferrite volumetric fraction in AISI 304 austenitic stainless steels were done by X-ray difraction, quantitative metallography (point count) and by means of one specific commercial apparatus whose operational principle is magnetic-inductive: The Ferrite Content Meter 1053 / Institut Dr. Forster. The results obtained were comparated with point count, the reference method. It was also investigated in these measurements the influence of the martensite induced by mechanical deformation. Determinations by X-ray diffraction, by the ratio between integrated intensities of the ferrite (211) and austenite (311) lines, are in excelent agreement with those taken by point count. One correction curve for the lectures of the commercial equipment in focus was obtained, for the range between zero and 20% of delta ferrite in 18/8 stainless steels. It is demonstrated that, depending on the employed measurement method and surface finishing of the material to be analysed, the presence of martensite produced by mechanical deformation of the austenitic matrix is one problem to be considered. (Author) [pt

  6. Theoretical and Experimental Estimations of Volumetric Inductive Phase Shift in Breast Cancer Tissue

    Science.gov (United States)

    González, C. A.; Lozano, L. M.; Uscanga, M. C.; Silva, J. G.; Polo, S. M.

    2013-04-01

    Impedance measurements based on magnetic induction for breast cancer detection has been proposed in some studies. This study evaluates theoretical and experimentally the use of a non-invasive technique based on magnetic induction for detection of patho-physiological conditions in breast cancer tissue associated to its volumetric electrical conductivity changes through inductive phase shift measurements. An induction coils-breast 3D pixel model was designed and tested. The model involves two circular coils coaxially centered and a human breast volume centrally placed with respect to the coils. A time-harmonic numerical simulation study addressed the effects of frequency-dependent electrical properties of tumoral tissue on the volumetric inductive phase shift of the breast model measured with the circular coils as inductor and sensor elements. Experimentally; five female volunteer patients with infiltrating ductal carcinoma previously diagnosed by the radiology and oncology departments of the Specialty Clinic for Women of the Mexican Army were measured by an experimental inductive spectrometer and the use of an ergonomic inductor-sensor coil designed to estimate the volumetric inductive phase shift in human breast tissue. Theoretical and experimental inductive phase shift estimations were developed at four frequencies: 0.01, 0.1, 1 and 10 MHz. The theoretical estimations were qualitatively in agreement with the experimental findings. Important increments in volumetric inductive phase shift measurements were evident at 0.01MHz in theoretical and experimental observations. The results suggest that the tested technique has the potential to detect pathological conditions in breast tissue associated to cancer by non-invasive monitoring. Further complementary studies are warranted to confirm the observations.

  7. Experimental and theoretical evaluation on the thermal performance of a windowed volumetric solar receiver

    International Nuclear Information System (INIS)

    Wang, P.; Li, J.B.; Bai, F.W.; Liu, D.Y.; Xu, C.; Zhao, L.; Wang, Z.F.

    2017-01-01

    In the present work, we carried out an experimental analysis on the thermal performance of a windowed volumetric solar receiver (WVSR). A prototype was designed and tested in a dish concentrator system. Three silicon carbide (SiC) absorber slabs with different typical pore structures were tested. A unified theoretical model adequately considering the overall heat transfer processes for the WVSR is first put forward. The key component, a windowed cavity incorporated with the irradiated surface of the absorber was modeled in a coupled radiative-convection boundary condition, which detailedly concerning the porous surface structure of the absorber under local thermal non-equilibrium conditions. Model authentication was achieved by comparing the experimental and theoretical results. The maximum temperature of the outlet air was over 1003 K, and the best thermal efficiency (solar to thermal) obtained was 63.61%. The maximum deviations in the results were 9.4% and 2.3% for the temperature of the back wall and the outlet air, respectively. In terms of the thermal efficiency, the maximum deviation was 5.35%. These results demonstrate the feasibility of our model applied to describe the overall transport process from solar to thermal energy in a receiver. - Highlights: • A prototype test is presented on a windowed volumetric solar receiver (WVSR). • A uniform theoretical heat transfer model for WVSR is first put forward. • Boundary condition coupling the porous absorber surface and window is developed. • Model validation is finished by comparing the experimental and numerical results.

  8. Determination of Mo in U-Mo alloy. EDTA volumetric method

    International Nuclear Information System (INIS)

    Wang Meiling; Wang Shu'an Hou Lieqi

    2005-10-01

    The determination methods of Mo are mentioned and EDTA volumetric method is proposed to determine the quantity of Mo in U-Mo alloy. According to the method, some condition experiments are done to confirm the quantity of some reagents. The results are satisfying. When the sample weight is 0.1-0.25 g, the precision is superior to 1% and the percent recovery is 99.2%-101.0%. (authors)

  9. Volumetric runoff coefficients for experimental rural catchments in the Iberian Peninsula

    Science.gov (United States)

    Taguas, Encarnación V.; Molina, Cecilio; Nadal-Romero, Estela; Ayuso, José L.; Casalí, Javier; Cid, Patricio; Dafonte, Jorge; Duarte, Antonio C.; Farguell, Joaquim; Giménez, Rafael; Giráldez, Juan V.; Gómez, Helena; Gómez, Jose A.; González-Hidalgo, J. Carlos; Keizer, J. Jacob; Lucía, Ana; Mateos, Luciano; Rodríguez-Blanco, M. Luz; Schnabel, Sussane; Serrano-Muela, M. Pilar

    2015-04-01

    crucial for designing appropriate decision making tools for water management. REFERENCES Chow V.T., Maidment D.R. and Mays, L.W. 1988. Applied Hydrology. MCGraw Hill, Nueva York. Dhakal, N., Fang, X., Cleveland, T., Thompson, D., Asquith, W., and Marzen, L. (2012). "Estimation of Volumetric Runoff Coefficients for Texas Watersheds Using Land-Use and Rainfall-Runoff Data." Journal of Irrigation and Drainage Engineering, 1(2012):43-54. Schaake JC, Geyer JC,Knapp JW. 1967. Experimental examination of the rational method. J. Hydr.Div. 93(6),353-70

  10. Headspace Volumetric Karl Fischer Titration for the Determination of Water Content in Finished Tobacco Products

    OpenAIRE

    Aydin N; Chardonnens F; Rotach M

    2014-01-01

    Because many physicochemical properties of tobacco are highly sensitive to its moisture content, the determination of water level is an important parameter for tobacco characterization. A headspace volumetric Karl Fischer titration (HS-V-KFT) method is presented for the quantification of water content in different finished tobacco materials. The parameters affecting the extraction of water from the tobacco materials were the sample size and the oven temperature which have been optimized. The ...

  11. Simple determination of sulfate ion in rain by volumetric methods using lead (II) nitrate and dithizone

    Energy Technology Data Exchange (ETDEWEB)

    Gu Yongzuo; Zhou Qizhi (Sichuan Univ., Chengdu, SC (China)); Iwatsuki, M.; Fukasawa, T. (Yamanashi Univ., Yamanashi (Japan). Faculty of Engineering)

    1993-05-10

    Nowadays, 'acid rain' is one of serious problems in the world. Sulfate ion is one of main constituents in the acid rain, and its rapid and reliable determination is very important for the application to a lot of samples. For its determination, turbidimetry, spectrophotometry and ion chromatography are generally employed. In this paper, volumetric methods are proposed for simple determination of sulfate ion in rain. Lead (II) nitrate and dithizone are used as titrant and indicator, respectively, and the end point is determined either visually or photometrically. Recovery ratio of ions, precision, and effect of foreign ions on determination of sulfate ion by the methods were studied, and compared with those by the turbidimetry and ion chromatography. The proposed methods, especially the visual titration has advantages of simplicity, rapidity, and suitability for routine analysis, and requires no expensive equipment. 5 refs., 4 tabs.

  12. Headspace Volumetric Karl Fischer Titration for the Determination of Water Content in Finished Tobacco Products

    Directory of Open Access Journals (Sweden)

    Aydin N

    2014-12-01

    Full Text Available Because many physicochemical properties of tobacco are highly sensitive to its moisture content, the determination of water level is an important parameter for tobacco characterization. A headspace volumetric Karl Fischer titration (HS-V-KFT method is presented for the quantification of water content in different finished tobacco materials. The parameters affecting the extraction of water from the tobacco materials were the sample size and the oven temperature which have been optimized. The extraction of water from the samples was achieved within a reasonable time (<25 min with a sample size of 200 mg and an optimum temperature of between 90 °C and 100 °C. The results of the water determination by HS-V-KFT at the optimized parameters were in good agreement with those obtained by standard volumetric Karl Fischer titration. HS-V-KFT showed very good repeatability (RSDr 0.9% and intermediate precision (RSDiR 1.1%. With respect to a considerable time saving, solvent consumption reduction, precision and accuracy, HS-V-KFT can therefore be suggested as the method of choice to determine water amount in finished tobacco products.

  13. Measurement of scattered radiation in a volumetric 64-slice CT scanner using three experimental techniques

    Energy Technology Data Exchange (ETDEWEB)

    Akbarzadeh, A; Ay, M R; Sarkar, S [Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ghadiri, H [Research Center for Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Zaidi, H [Division of Nuclear Medicine, Geneva University Hospital, CH-1211 Geneva (Switzerland)], E-mail: mohammadreza_ay@tums.ac.ir

    2010-04-21

    Compton scatter poses a significant threat to volumetric x-ray computed tomography, bringing cupping and streak artefacts thus impacting qualitative and quantitative imaging procedures. To perform appropriate scatter compensation, it is necessary to estimate the magnitude and spatial distribution of x-ray scatter. The aim of this study is to compare three experimental methods for measurement of the scattered radiation profile in a 64-slice CT scanner. The explored techniques involve the use of collimator shadow, a single blocker (a lead bar that suppresses the primary radiation) and an array blocker. The latter was recently proposed and validated by our group. The collimator shadow technique was used as reference for comparison since it established itself as the most accurate experimental procedure available today. The mean relative error of measurements in all tube voltages was 3.9 {+-} 5.5% (with a maximum value of 20%) for the single blocker method whereas it was 1.4 {+-} 1.1% (with a maximum value of 5%) for the proposed blocker array method. The calculated scatter-to-primary ratio (SPR) using the blocker array method for the tube voltages of 140 kVp and 80 kVp was 0.148 and 1.034, respectively. For a larger polypropylene phantom, the maximum SPR achieved was 0.803 and 6.458 at 140 kVp and 80 kVp, respectively. Although the three compared methods present a reasonable accuracy for calculation of the scattered profile in the region corresponding to the object, the collimator shadow method is by far the most accurate empirical technique. Nevertheless, the blocker array method is relatively straightforward for scatter estimation providing minor additional radiation exposure to the patient.

  14. Validation of simultaneous volumetric and spectrophotometric methods for the determination of captopril in pharmaceutical formulations.

    Science.gov (United States)

    Rahman, Nafisur; Singh, Manisha; Hoda, Nasrul

    2005-01-01

    Simple, sensitive and economical simultaneous volumetric and spectrophotometric methods for the determination of captopril have been developed. The methods were based on the reaction of captopril with potassium iodate in HCl medium. Amaranth was used as indicator to detect the end-point of the titration in aqueous layer. The iodine formed during the titration was extracted into CCl4 and subsequently determined spectrophotometrically at 510 nm. The Beer's law was obeyed in the concentration range of 120-520 microg ml-1. Rigorous statistical analyses were performed for the validation of the proposed methods. The proposed methods were successfully applied to the determination of captopril in dosage forms. Comparison of the means of the proposed procedures with those of reference methods using point and interval hypothesis tests showed no statistically significant difference.

  15. Gravimetric and volumetric determination of the purity of electrolytically refined silver and the produced silver nitrate

    Directory of Open Access Journals (Sweden)

    Ačanski Marijana M.

    2007-01-01

    Full Text Available Silver is, along with gold and the platinum-group metals, one of the so called precious metals. Because of its comparative scarcity, brilliant white color, malleability and resistance to atmospheric oxidation, silver has been used in the manufacture of coins and jewelry for a long time. Silver has the highest known electrical and thermal conductivity of all metals and is used in fabricating printed electrical circuits, and also as a coating for electronic conductors. It is also alloyed with other elements such as nickel or palladium for use in electrical contacts. The most useful silver salt is silver nitrate, a caustic chemical reagent, significant as an antiseptic and as a reagent in analytical chemistry. Pure silver nitrate is an intermediate in the industrial preparation of other silver salts, including the colloidal silver compounds used in medicine and the silver halides incorporated into photographic emulsions. Silver halides become increasingly insoluble in the series: AgCl, AgBr, AgI. All silver salts are sensitive to light and are used in photographic coatings on film and paper. The ZORKA-PHARMA company (Sabac, Serbia specializes in the production of pharmaceutical remedies and lab chemicals. One of its products is chemical silver nitrate (argentum-nitricum (l. Silver nitrate is generally produced by dissolving pure electrolytically refined silver in hot 48% nitric acid. Since the purity of silver nitrate, produced in 2002, was not in compliance with the p.a. level of purity, there was doubt that the electrolytically refined silver was pure. The aim of this research was the gravimetric and volumetric determination of the purity of electrolytically refined silver and silver nitrate, produced industrially and in a laboratory. The purity determination was carried out gravimetrically, by the sedimentation of silver(I ions in the form of insoluble silver salts: AgCl, AgBr and Agi, and volumetrically, according to Mohr and Volhardt. The

  16. Volumetric pulp changes after orthodontic treatment determined by cone-beam computed tomography.

    Science.gov (United States)

    Venkatesh, Shivanand; Ajmera, Shreya; Ganeshkar, Sanjay V

    2014-11-01

    The purpose of this study was to observe and evaluate 3-dimensional pulp cavity changes during orthodontic treatment. Eighty-seven patients formed the study sample and were divided into an experimental group (48 patients) and a control group (39 patients). Cone-beam computed tomographic (CBCT) records were obtained before the start of the treatment (T0) and after space closure for the experimental group, whereas for the control group CBCT images were obtained approximately 17-18 months (T1) after obtaining the first image (T0). CBCT data were reconstructed with surface and volume rendering software (Mimics; Materialise, Leuven, Belgium), and the volumetric images were modified to display the teeth from various orientations. Six anterior teeth were segmented and their pulps isolated. Paired t test was used to check for statistical significance. The difference in the pulp volume was statistically significant at P Orthodontic treatment in the experimental group produced a significant decrease in the size of the pulp, which was statistically significant. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. Determination of iodide by volumetric titration in support of the oil eletrolabeling with {sup 123}I

    Energy Technology Data Exchange (ETDEWEB)

    Kenup-Cantuaria, Hericka O.H.; Brandao, Luis E.B., E-mail: hkenup@ien.gov.br, E-mail: brandao@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Silva, Ademir X., E-mail: ademir@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2015-07-01

    The accuracy in measuring flow rate in pipelines is essential task to control various technical parameters in an industrial plant in oil industry and its derivatives. For this reason, it becomes increasingly widespread the uses of organic molecules labeled with radioactive isotopes mainly because of the wide possibility in use of different radioisotopes also due to the new labeling techniques. This paper presents a study to develop an electrochemical technique for oil labeling with iodine -123 and to determine the yield of production by measuring the concentration of iodide (I{sup -}) during this process. The volumetric titration technique was applied as a basis for quantitative and qualitative measures to monitor the labeling process. The results indicate the technical proposal as a viable alternative for monitoring electro labeling process of lubricating oils with iodine -123. (author)

  18. Experimental determination of Ramsey numbers.

    Science.gov (United States)

    Bian, Zhengbing; Chudak, Fabian; Macready, William G; Clark, Lane; Gaitan, Frank

    2013-09-27

    Ramsey theory is a highly active research area in mathematics that studies the emergence of order in large disordered structures. Ramsey numbers mark the threshold at which order first appears and are extremely difficult to calculate due to their explosive rate of growth. Recently, an algorithm that can be implemented using adiabatic quantum evolution has been proposed that calculates the two-color Ramsey numbers R(m,n). Here we present results of an experimental implementation of this algorithm and show that it correctly determines the Ramsey numbers R(3,3) and R(m,2) for 4≤m≤8. The R(8,2) computation used 84 qubits of which 28 were computational qubits. This computation is the largest experimental implementation of a scientifically meaningful adiabatic evolution algorithm that has been done to date.

  19. Volumetric characterization of the flow over miniature wind farms: An experimental study

    Science.gov (United States)

    Wing, Lai; Troolin, Dan; Hyun, Jin Kim; Tobin, Nicolas; Zuniga Zamalloa, Carlo; Chamorro, Leonardo P.

    2014-11-01

    An internal boundary layer is known to develop from the interaction between wind farms and the atmospheric boundary layer. It possesses characteristic features able to modulate the turbulence dynamics over large regions and eventually modify the micro climate in the vicinity of the wind farm. In this study, we examine the structure of the turbulence above various miniature wind farm configurations using 3D Particle Image velocimetry (PIV). Each miniature wind farm is placed in the boundary-layer wind tunnel at the Mechanical Science Engineering, UIUC. The turbines are fabricated using 3D printing and have a loading system that controls their tip-speed ratio and allows for characterizing the loads. Volumetric PIV is performed at various locations over and downstream a series of wind farm layouts. High-order turbulence statistics, turbulence structure and characteristic coherent motions are obtained and discussed in terms of the wind farm layout.

  20. Volumetric Titrations Using Electrolytically Generated Reagents for the Determination of Ascorbic Acid and Iron in Dietary Supplement Tablets: An Undergraduate Laboratory Experiment

    Science.gov (United States)

    Scanlon, Christopher; Gebeyehu, Zewdu; Griffin, Kameron; Dabke, Rajeev B.

    2014-01-01

    An undergraduate laboratory experiment for the volumetric quantitative analysis of ascorbic acid and iron in dietary supplement tablets is presented. Powdered samples of the dietary supplement tablets were volumetrically titrated against electrolytically generated reagents, and the mass of dietary reagent in the tablet was determined from the…

  1. Simulation of volumetrically heated pebble beds in solid breeding blankets for fusion reactors. Modelling, experimental validation and sensitivity studies

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Gonzalez, Francisco Alberto

    2016-10-14

    The Breeder Units contains pebble beds of lithium orthosilicate (Li{sub 4}SiO{sub 4}) as tritium breeder material and beryllium as neutron multiplier. In this dissertation a closed validation strategy for the thermo-mechanical validation of the Breeder Units has been developed. This strategy is based on the development of dedicated testing and modeling tools, which are needed for the qualification of the thermo-mechanical functionality of these components in an out-of-pile experimental campaign. The neutron flux in the Breeder Units induces a nonhomogeneous volumetric heating in the pebble beds that must be mimicked in an out-of-pile experiment with an external heating system minimizing the intrusion in the pebble beds. Therefore, a heater system that simulates this volumetric heating has been developed. This heater system is based on ohmic heating and linear heater elements, which approximates the point heat sources of the granular material by linear sources. These linear sources represent ''linear pebbles'' in discrete locations close enough to relatively reproduce the thermal gradients occurring in the functional materials. The heater concept has been developed for the Li{sub 4}SiO{sub 4} and it is based on a hexagonal matrix arrangement of linear and parallel heater elements of diameter 1 mm separated by 7 mm. A set of uniformly distributed thermocouples in the transversal and longitudinal direction in the pebble bed midplane allows a 2D temperature reconstruction of that measurement plane by means of biharmonic spline interpolation. This heating system has been implemented in a relevant Breeder Unit region and its proof-of-concept has been tested in a PRE-test Mock-Up eXperiment (PREMUX) that has been designed and constructed in the frame of this dissertation. The packing factor of the pebble bed with and without the heating system does not show significant differences, giving an indirect evidence of the low intrusion of the system. Such

  2. Microfluidic volumetric flow determination using optical coherence tomography speckle: An autocorrelation approach

    Energy Technology Data Exchange (ETDEWEB)

    De Pretto, Lucas R., E-mail: lucas.de.pretto@usp.br; Nogueira, Gesse E. C.; Freitas, Anderson Z. [Instituto de Pesquisas Energéticas e Nucleares, IPEN–CNEN/SP, Avenida Lineu Prestes, 2242, 05508-000 São Paulo (Brazil)

    2016-04-28

    Functional modalities of Optical Coherence Tomography (OCT) based on speckle analysis are emerging in the literature. We propose a simple approach to the autocorrelation of OCT signal to enable volumetric flow rate differentiation, based on decorrelation time. Our results show that this technique could distinguish flows separated by 3 μl/min, limited by the acquisition speed of the system. We further perform a B-scan of gradient flow inside a microchannel, enabling the visualization of the drag effect on the walls.

  3. A modified differential scanning calorimetry for determination of cell volumetric change during the freezing process.

    Science.gov (United States)

    Luo, Dawei; Han, Xu; He, Liqun; Cui, Xiangdong; Cheng, Shuxia; Lu, Caicheng; Liu, Jianghan; Gao, Dayong

    2002-01-01

    A modified analytical and experimental method using differential scanning calorimeter (DSC) was developed to determine the cell volume change during the freezing process. Two cell types were used in the study: human platelets and erythrocytes (red blood cells). Isotonic cell suspensions with different cytocrits were prepared and used in the DSC experiments. Low cooling rates were used to avoid intracellular ice formation. Cell suspensions were cooled from room temperature to -40 degrees C. Latent heat release from the freezing of cell suspensions was shown to be a linear function of cytocrit. From slope and intercept of the linear function, cell volume change was determined based on a developed theoretical model. From experimental data and theoretical analyses, it was revealed that (a) the final volume of a human platelet at -40 degrees C was 33.7% of its isotonic volume, and 15.2% of the original (at isotonic condition) intracellular water remained unfrozen inside platelets, and (b) the final volume of human erythrocyte at -40 degrees C was 50.0% of its isotonic volume, and 30.3% of the original intracellular water was kept inside cells as residual unfrozen water.

  4. Volumetric determination of hydroxide, aluminate, and carbonate in alkaline solutions of nuclear waste

    International Nuclear Information System (INIS)

    Baumann, E.W.

    1975-06-01

    An integrated procedure was developed for determining OH - , Al(OH) 4 - , and CO 3 2- in alkaline nuclear waste. The free alkali, the hydroxide released when Al(OH) 3 is complexed with oxalate, and the precipitated BaCO 3 were determined by acidimetric titration. With a 50-μl sample, the relative standard deviations were 1 to 2 percent for nonradioactive test solutions and 2 to 5 percent for radioactive process solutions. (U.S.)

  5. SU-F-J-47: Inherent Uncertainty in the Positional Shifts Determined by a Volumetric Cone Beam Imaging System

    Energy Technology Data Exchange (ETDEWEB)

    Giri, U; Ganesh, T; Saini, V; Munshi, A; Sarkar, B; Mohanti, B [Fortis Memorial Research Institute, Gurgaon, Haryana (India)

    2016-06-15

    Purpose: To quantify inherent uncertainty associated with a volumetric imaging system in its determination of positional shifts. Methods: The study was performed on an Elekta Axesse™ linac’s XVI cone beam computed tomography (CBCT) system. A CT image data set of a Penta- Guide phantom was used as reference image by placing isocenter at the center of the phantom.The phantom was placed arbitrarily on the couch close to isocenter and CBCT images were obtained. The CBCT dataset was matched with the reference image using XVI software and the shifts were determined in 6-dimensions. Without moving the phantom, this process was repeated 20 times consecutively within 30 minutes on a single day. Mean shifts and their standard deviations in all 6-dimensions were determined for all the 20 instances of imaging. For any given day, the first set of shifts obtained was kept as reference and the deviations of the subsequent 19 sets from the reference set were scored. Mean differences and their standard deviations were determined. In this way, data were obtained for 30 consecutive working days. Results: Tabulating the mean deviations and their standard deviations observed on each day for the 30 measurement days, systematic and random errors in the determination of shifts by XVI software were calculated. The systematic errors were found to be 0.03, 0.04 and 0.03 mm while random errors were 0.05, 0.06 and 0.06 mm in lateral, craniocaudal and anterio-posterior directions respectively. For rotational shifts, the systematic errors were 0.02°, 0.03° and 0.03° and random errors were 0.06°, 0.05° and 0.05° in pitch, roll and yaw directions respectively. Conclusion: The inherent uncertainties in every image guidance system should be assessed and baseline values established at the time of its commissioning. These shall be periodically tested as part of the QA protocol.

  6. SU-F-J-47: Inherent Uncertainty in the Positional Shifts Determined by a Volumetric Cone Beam Imaging System

    International Nuclear Information System (INIS)

    Giri, U; Ganesh, T; Saini, V; Munshi, A; Sarkar, B; Mohanti, B

    2016-01-01

    Purpose: To quantify inherent uncertainty associated with a volumetric imaging system in its determination of positional shifts. Methods: The study was performed on an Elekta Axesse™ linac’s XVI cone beam computed tomography (CBCT) system. A CT image data set of a Penta- Guide phantom was used as reference image by placing isocenter at the center of the phantom.The phantom was placed arbitrarily on the couch close to isocenter and CBCT images were obtained. The CBCT dataset was matched with the reference image using XVI software and the shifts were determined in 6-dimensions. Without moving the phantom, this process was repeated 20 times consecutively within 30 minutes on a single day. Mean shifts and their standard deviations in all 6-dimensions were determined for all the 20 instances of imaging. For any given day, the first set of shifts obtained was kept as reference and the deviations of the subsequent 19 sets from the reference set were scored. Mean differences and their standard deviations were determined. In this way, data were obtained for 30 consecutive working days. Results: Tabulating the mean deviations and their standard deviations observed on each day for the 30 measurement days, systematic and random errors in the determination of shifts by XVI software were calculated. The systematic errors were found to be 0.03, 0.04 and 0.03 mm while random errors were 0.05, 0.06 and 0.06 mm in lateral, craniocaudal and anterio-posterior directions respectively. For rotational shifts, the systematic errors were 0.02°, 0.03° and 0.03° and random errors were 0.06°, 0.05° and 0.05° in pitch, roll and yaw directions respectively. Conclusion: The inherent uncertainties in every image guidance system should be assessed and baseline values established at the time of its commissioning. These shall be periodically tested as part of the QA protocol.

  7. Experimental determination of mechanical parameters in sensorless ...

    Indian Academy of Sciences (India)

    The speed controller design in such a drive is highly sensitive to the mechanical parameters of the induction motor. These mechanical parameters change with the load coupled. This paper proposes a method to experimentally determine the moment of inertia and mechanical time constant of the induction motor drive along ...

  8. Volumetric determination of methanol in ammonium uranil carbonate of nuclear purity

    International Nuclear Information System (INIS)

    Lorenzatto, R.L.

    1989-01-01

    The method developed allows to determine methanol in ammonium uranil carbonate (AUC) from a concentration of 0.01 % with great accuracy. The ammonium uranil carbonate is dissolved in pre-established volumes of a potassium dichromate and concentrated sulfuric acid standardized solution. Instantaneously, the methanol presents oxidates at formic acid, reducing an equivalent amount of dichromate. The remaining dichromate still present, is reduced by adding in excess a standardized solution of ferrous sulphate. The titration of this excess with a standardized solution of potassium permanganate, using ferrous o- phenanthroline as indicator, will give a net and sensitive final point which allows to obtain by a simple estimate the percentage of methanol in the analyzed sample with great precision. Besides, essays are included which were carried out with the aim of proving and putting into evidence in a practical way that the high volatility of the methanol contained in an ammonium uranil carbonate will be the main disadvantage causing errors in defect. Observations for those requesting these analyses and for analysts performing them are mentioned in order to minimize the error factor abovementioned. (Author) [es

  9. Size determination and response assessment of liver metastases with computed tomography—Comparison of RECIST and volumetric algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Rothe, Jan Holger, E-mail: jan-holger.rothe@charite.de [Klinik für Radiologie, Campus Virchow-Klinikum, Charité – Universitätsmedizin, Berlin (Germany); Grieser, Christian [Klinik für Radiologie, Campus Virchow-Klinikum, Charité – Universitätsmedizin, Berlin (Germany); Lehmkuhl, Lukas [Abteilung für Diagnostische und Interventionelle Radiologie, Herzzentrum Leipzig (Germany); Schnapauff, Dirk; Fernandez, Carmen Perez; Maurer, Martin H.; Mussler, Axel; Hamm, Bernd; Denecke, Timm; Steffen, Ingo G. [Klinik für Radiologie, Campus Virchow-Klinikum, Charité – Universitätsmedizin, Berlin (Germany)

    2013-11-01

    Objective: To compare different three-dimensional volumetric algorithms (3D-algorithms) and RECIST for size measurement and response assessment in liver metastases from colorectal and pancreatic cancer. Methods: The volumes of a total of 102 liver metastases in 45 patients (pancreatic cancer, n = 22; colon cancer, n = 23) were estimated using three volumetric methods (seeded region growing method, slice-based segmentation, threshold-based segmentation) and the RECIST 1.1 method with volume calculation based on the largest axial diameter. Each measurement was performed three times by one observer. All four methods were applied to follow-up on 55 liver metastases in 29 patients undergoing systemic treatment (median follow-up, 3.5 months; range, 1–10 months). Analysis of variance (ANOVA) with post hoc tests was performed to analyze intraobserver variability and intermethod differences. Results: ANOVA showed significant higher volumes calculated according to the RECIST guideline compared to the other measurement methods (p < 0.001) with relative differences ranging from 0.4% to 41.1%. Intraobserver variability was significantly higher (p < 0.001) for RECIST and threshold based segmentation (3.6–32.8%) compared with slice segmentation (0.4–13.7%) and seeded region growing method (0.6–10.8%). In the follow-up study, the 3D-algorithms and the assessment following RECIST 1.1 showed a discordant classification of treatment response in 10–21% of the patients. Conclusions: This study supports the use of volumetric measurement methods due to significant higher intraobserver reproducibility compared to RECIST. Substantial discrepancies in tumor response classification between RECIST and volumetric methods depending on applied thresholds confirm the requirement of a consensus concerning volumetric criteria for response assessment.

  10. Experimental investigation of the liquid volumetric mass transfer coefficient for upward gas-liquid two-phase flow in rectangular microchannels

    Directory of Open Access Journals (Sweden)

    X. Y. Ji

    2010-12-01

    Full Text Available The gas-liquid two-phase mass transfer process in microchannels is complicated due to the special dynamical characteristics. In this work, a novel method was explored to measure the liquid side volumetric mass transfer coefficient kLa. Pressure transducers were utilized to measure the pressure variation of upward gas-liquid two-phase flow in three vertical rectangular microchannels and the liquid side volumetric mass transfer coefficient kLa was calculated through the Pressure-Volume-Temperature correlation of the gas phase. Carbon dioxide-water, carbon dioxide-ethanol and carbon dioxide-n-propanol were used as working fluids, respectively. The dimensions of the microchannels were 40 µm×240 µm (depth×width, 100 µm×800 µm and 100 µm×2000 µm, respectively. Results showed that the channel diameter and the capillary number influence kLa remarkably and that the maximum value of kLa occurs in the annular flow regime. A new correlation of kLa was proposed based on the Sherwood number, Schmidt number and the capillary number. The predicted values of kLa agreed well with the experimental data.

  11. Parametric model of volumetric scattering

    Science.gov (United States)

    Magarill, Simon; Cassarly, William J.; Jenkins, David R.; Yang, Yang; Yu, Xiaofeng; Liu, Guang

    2017-11-01

    We develop a method to determine volumetric scattering model parameter values based on measured BSDF characteristics. Example models often use Mie or Gegenbauer particles. The accuracy and flexibility of this approach are illustrated.

  12. Patterns of shading tolerance determined from experimental ...

    Science.gov (United States)

    An extensive review of the experimental literature on seagrass shading evaluated the relationship between experimental light reductions, duration of experiment and seagrass response metrics to determine whether there were consistent statistical patterns. There were highly significant linear relationships of both percent biomass and percent shoot density reduction versus percent light reduction (versus controls), although unexplained variation in the data were high. Duration of exposure affected extent of response for both metrics, but was more clearly a factor in biomass response. Both biomass and shoot density showed linear responses to duration of light reduction for treatments 60%. Unexplained variation was again high, and greater for shoot density than biomass. With few exceptions, regressions of both biomass and shoot density on light reduction for individual species and for genera were statistically significant, but also tended to show high degrees of variability in data. Multivariate regressions that included both percent light reduction and duration of reduction as dependent variables increased the percentage of variation explained in almost every case. Analysis of response data by seagrass life history category (Colonizing, Opportunistic, Persistent) did not yield clearly separate response relationships in most cases. Biomass tended to show somewhat less variation in response to light reduction than shoot density, and of the two, may be the prefe

  13. Development of a volumetric Analysis method to determine uranium in the loaded phosphoric acid and the loaded organic phase (DEHPA/TOPO)

    International Nuclear Information System (INIS)

    Shlewit, H.; Koudsi, Y.

    2003-01-01

    Rapid and reliable volumetric analysis method has been developed to determine uranium, on line, at uranium extraction unit from wet-process phosphoric acid, in aqueous and organic phases. This process enable up 300 mg of uranium to be determined in the presence of nitric acid, in a sample volume of up to at least 10 ml. The volume of the sample, the amounts of reagents added, the temperature of the reagents and the standing time of various stages were investigated to ensure that the conditions selected for the final procedure were reasonably non-critical

  14. Experimental determination of chlorite dissolution rates

    International Nuclear Information System (INIS)

    Rochelle, C.A.; Bateman, K.; MacGregor, R.; Pearce, J.M.; Wetton, P.D.; Savage, D.

    1995-01-01

    Current concepts of the geological disposal of low- and intermediate-level radioactive wastes in the UK envisage the construction of a mined facility (incorporating cementitious engineered barriers) in chlorite-bearing rocks. To model accurately the fluid-rock reactions within the disturbed zone surrounding a repository requires functions that describe mineral dissolution kinetics under pH conditions that vary from near neutral to highly alkaline. Therefore, an experimental study to determine the dissolution rates of Fe-rich chlorite has been undertaken as part of the Nirex Safety Assessment Research Program. Four experiments have been carried out at 25 C and four at 70 C, both sets using a range of NaCl/NaOH solutions of differing pH (of nominal pH 9.0, 10.3, 11.6 and 13.0 [at 25 C]). Dissolution rates have been calculated and were found to increase with increasing pH and temperature. However, increased pH resulted in non-stoichiometric dissolution possibly due to preferential dissolution of part of the chlorite structure relative to another, or reprecipitation of some elements as thin hydroxide or oxyhydroxide surface coatings on the chlorite. These results also show that chlorite dissolution is appreciably slower than that of albite and quartz at both 25 and 70 C, but slightly faster than that of muscovite at 70 C

  15. Volumetric composition of nanocomposites

    DEFF Research Database (Denmark)

    Madsen, Bo; Lilholt, Hans; Mannila, Juha

    2015-01-01

    . An analytical model, previously established for conventional fibre composites, is used for the analysis of the volumetric composition. For the aluminosilicate/polylactate nanocomposites, based on the established linear relationship between the porosity content and the fibre volume content, the fibre correlated...... porosity factor is determined to be 0.18. Geometrical considerations of the packing of parallel nanofibres in a square array are used to make the assumption that the maximum obtainable fibre volume content in the nanocomposites will not exceed 6 % due to the small fibre spacing that restricts full matrix...... significant figures. The plotting of the measured nanocomposite density as a function of the nanofibre weight content is shown to be a first good approach of assessing the porosity content of the materials. The known gravimetric composition of the nanocomposites is converted into a volumetric composition...

  16. Volumetric integration model of the Stiles-Crawford effect of the first kind and its experimental verification.

    Science.gov (United States)

    Vohnsen, Brian; Carmichael, Alessandra; Sharmin, Najnin; Qaysi, Salihah; Valente, Denise

    2017-10-01

    The integrated Stiles-Crawford function is commonly used as apodization model for vision through the natural eye pupil. However, this method does not account for possible effects related to the retinal thickness, the large length-to-diameter aspect ratio of the photoreceptors, or the use of nonMaxwellian illumination. Here, we introduce a geometrical optics model to calculate the fraction of overlap between light at the retina and the photoreceptor outer segments where absorption triggers vision. The model, which does not account for photoreceptor waveguiding, is discussed for both Maxwellian and nonMaxwellian illumination. The integrated Stiles-Crawford effect is analyzed experimentally with a uniaxial pupil-size flicker methodology and we find that the psychophysical measurements match better to the geometrical optics predictions than direct integration of a Stiles-Crawford function.

  17. Experimental determination of mechanical parameters in sensorless ...

    Indian Academy of Sciences (India)

    V S S PAVAN KUMAR HARI

    The proposed method is based on acceleration and deceleration of the motor under constant torque, which is achieved using a sensorless vector-controlled drive itself. Experimental results from a 5-hp induction motor drive are presented. Keywords. Induction motor drives; field-oriented control; moment of inertia; frictional ...

  18. Experimental determination of high angular momentum states

    International Nuclear Information System (INIS)

    Barreto, J.L.V.

    1985-01-01

    The current knowledge of the atomic nucleus structure is summarized. A short abstract of the nuclear properties at high angular momentum and a more detailed description of the experimental methods used in the study of high angular momenta is made. (L.C.) [pt

  19. Experimental determination of contraction coefficient and velocity ...

    Indian Academy of Sciences (India)

    Jailakshmi Menon

    2018-04-16

    Apr 16, 2018 ... conditions are obtained from the measured jet velocity and the discharge. .... hence the measurement of jet thickness will not be accurate. In this study .... Sump. Suction pipe. Venturimeter. Valve. Return channel. Figure 4. Schematic sketch of the experimental setup. 61 Page 4 of 9. SЕdhanЕ (2018) 43:61 ...

  20. Volumetric and viscometric properties of binary mixtures of {l_brace}methyl tert-butyl ether (MTBE) + alcohol{r_brace} at several temperatures and p = 0.1 MPa: Experimental results and application of the ERAS model

    Energy Technology Data Exchange (ETDEWEB)

    Hoga, H.E. [Departamento de Engenharia Quimica, Centro Universitario da FEI, Avenida Humberto de Alencar, Castelo Branco 3972, 09850-901 Sao Bernardo do Campo, Sao Paulo (Brazil); Torres, R.B., E-mail: belchior@fei.edu.br [Departamento de Engenharia Quimica, Centro Universitario da FEI, Avenida Humberto de Alencar, Castelo Branco 3972, 09850-901 Sao Bernardo do Campo, Sao Paulo (Brazil)

    2011-08-15

    Highlights: > Binary mixtures of MTBE + alcohol have been studied. > Volumetric and viscometric properties have been determined at several temperatures. > Excess molar volumes have been used to test the applicability of the ERAS model. > The results are discussed in terms of chemical and structural effects. - Abstract: Densities and viscosities of binary mixtures of {l_brace}methyl tert-butyl ether (MTBE) + methanol, or +ethanol, or +1-propanol, or +2-propanol, or +1-butanol, or +1-pentanol, or +1-hexanol{r_brace} have been determined as a function of composition at several temperatures and atmospheric pressure. The temperatures studied were (293.15, 298.15, 303.15, and 308.15) K. The experimental results have been used to calculate the excess molar volume (V{sub m}{sup E}) and viscosity deviation ({Delta}{eta}). Both V{sub m}{sup E} and {Delta}{eta} values were negative over the entire range of mole fraction for all temperatures and systems studied. Moreover, the V{sub m}{sup E} values have been used to test the applicability of the Extended Real Associated Solution (ERAS) model.

  1. An Experimental Determination of Thermodynamic Values

    Science.gov (United States)

    Antony, Erling; Muccianti, Christine; Vogel, Tracy

    2012-01-01

    Measurements have been added to an old demonstration of chemical equilibria allowing the determination of thermodynamic constants. The experiment allows the students an opportunity to merge qualitative observations associated with Le Chatelier's principle and thermodynamic calculations using graphical techniques. (Contains 4 figures.)

  2. Determinants of Littering: An Experimental Analysis

    OpenAIRE

    Fatima Salim Khawaja; Anwar Shah

    2013-01-01

    Littering, the improper disposal of small quantities of waste, is one of the main causes of environmental degradation. To protect the environment from this degradation, we need to factor out the determinants of littering behaviour. In this study, we conduct a controlled laboratory experiment to examine whether people would avoid littering if the social cost of this behaviour was internalised. Based on the microeconomic theory relating to externality, we test whether penalising littering decre...

  3. Determination of action thresholds for electromagnetic tracking system-guided hypofractionated prostate radiotherapy using volumetric modulated arc therapy

    International Nuclear Information System (INIS)

    Zhang, Pengpeng; Mah, Dennis; Happersett, Laura; Cox, Brett; Hunt, Margie; Mageras, Gig

    2011-01-01

    Purpose: Hypofractionated prostate radiotherapy may benefit from both volumetric modulated arc therapy (VMAT) due to shortened treatment time and intrafraction real-time monitoring provided by implanted radiofrequency(RF) transponders. The authors investigate dosimetrically driven action thresholds (whether treatment needs to be interrupted and patient repositioned) in VMAT treatment with electromagnetic (EM) tracking. Methods: VMAT plans for five patients are generated for prescription doses of 32.5 and 42.5 Gy in five fractions. Planning target volume (PTV) encloses the clinical target volume (CTV) with a 3 mm margin at the prostate-rectal interface and 5 mm elsewhere. The VMAT delivery is modeled using 180 equi-spaced static beams. Intrafraction prostate motion is simulated in the plan by displacing the beam isocenter at each beam assuming rigid organ motion according to a previously recorded trajectory of the transponder centroid. The cumulative dose delivered in each fraction is summed over all beams. Two sets of 57 prostate motion trajectories were randomly selected to form a learning and a testing dataset. Dosimetric end points including CTV D95%, rectum wall D1cc, bladder wall D1cc, and urethra Dmax, are analyzed against motion characteristics including the maximum amplitude of the anterior-posterior (AP), superior-inferior (SI), and left-right components. Action thresholds are triggered when intrafraction motion causes any violations of dose constraints to target and organs at risk (OAR), so that treatment is interrupted and patient is repositioned. Results: Intrafraction motion has a little effect on CTV D95%, indicating PTV margins are adequate. Tight posterior and inferior action thresholds around 1 mm need to be set in a patient specific manner to spare organs at risk, especially when the prescription dose is 42.5 Gy. Advantages of setting patient specific action thresholds are to reduce false positive alarms by 25% when prescription dose is low, and

  4. Determination of action thresholds for electromagnetic tracking system-guided hypofractionated prostate radiotherapy using volumetric modulated arc therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Pengpeng; Mah, Dennis; Happersett, Laura; Cox, Brett; Hunt, Margie; Mageras, Gig [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021 (United States); Department of Radiation Oncology, Montefiore Medical Center, Bronx, New York 10467 (United States); Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021 (United States); Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021 (United States); Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021 (United States)

    2011-07-15

    Purpose: Hypofractionated prostate radiotherapy may benefit from both volumetric modulated arc therapy (VMAT) due to shortened treatment time and intrafraction real-time monitoring provided by implanted radiofrequency(RF) transponders. The authors investigate dosimetrically driven action thresholds (whether treatment needs to be interrupted and patient repositioned) in VMAT treatment with electromagnetic (EM) tracking. Methods: VMAT plans for five patients are generated for prescription doses of 32.5 and 42.5 Gy in five fractions. Planning target volume (PTV) encloses the clinical target volume (CTV) with a 3 mm margin at the prostate-rectal interface and 5 mm elsewhere. The VMAT delivery is modeled using 180 equi-spaced static beams. Intrafraction prostate motion is simulated in the plan by displacing the beam isocenter at each beam assuming rigid organ motion according to a previously recorded trajectory of the transponder centroid. The cumulative dose delivered in each fraction is summed over all beams. Two sets of 57 prostate motion trajectories were randomly selected to form a learning and a testing dataset. Dosimetric end points including CTV D95%, rectum wall D1cc, bladder wall D1cc, and urethra Dmax, are analyzed against motion characteristics including the maximum amplitude of the anterior-posterior (AP), superior-inferior (SI), and left-right components. Action thresholds are triggered when intrafraction motion causes any violations of dose constraints to target and organs at risk (OAR), so that treatment is interrupted and patient is repositioned. Results: Intrafraction motion has a little effect on CTV D95%, indicating PTV margins are adequate. Tight posterior and inferior action thresholds around 1 mm need to be set in a patient specific manner to spare organs at risk, especially when the prescription dose is 42.5 Gy. Advantages of setting patient specific action thresholds are to reduce false positive alarms by 25% when prescription dose is low, and

  5. Determination of ultra-trace amounts of prosthesis-related metals in whole blood using volumetric absorptive micro-sampling and tandem ICP - Mass spectrometry.

    Science.gov (United States)

    Bolea-Fernandez, Eduardo; Phan, Kim; Balcaen, Lieve; Resano, Martín; Vanhaecke, Frank

    2016-10-19

    This paper reports on an evaluation of the suitability of a novel sample collection approach, volumetric absorptive micro-sampling (VAMS), in the context of the determination of ultra-trace concentrations of prosthesis-related metals (Al, Ti, V, Co, Cr, Ni, Sr and Zr) in whole blood. In a first phase, a simple dilute-and-shoot approach (100-fold dilution) followed by tandem ICP - mass spectrometry (ICP-MS/MS) analysis was developed for the accurate and sensitive determination of the target elements. The ICP-MS/MS method relies on the use of mass shift reactions proceeding when pressurizing the collision/reaction cell (CRC) with CH 3 F/He for dealing with spectral overlap. Limits of detection (LoDs) between 0.3 and 30 ng L -1 were attained in a multi-element approach. The accuracy of the method was demonstrated via successful analysis of the reference materials Seronorm Whole Blood Levels 1 and 3, and real venous blood samples, spiked with the target elements at different concentration levels (5-50 μg L -1 ). Although the implementation of VAMS devices introduced contamination problems for Al, Cr and Ni, VAMS followed by ICP-MS/MS analysis shows potential for future real-life routine applications when assessing levels of Ti, V, Co, Sr and/or Zr. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Determination of experimental K-shell fluorescence yield for ...

    Indian Academy of Sciences (India)

    K-shell fluorescence yields were experimentally determined for potassium and calcium compounds using a Si(Li) X-ray detector system (FWHM=5.96 keV at 160 eV). The samples were excited by 5.96 keV photons produced by a 55Fe radioisotope source. The experimental values are systematically lower than the ...

  7. An approach to understanding tribological behaviour of dental composites through volumetric wear loss and wear mechanism determination; beyond material ranking.

    Science.gov (United States)

    Altaie, Asmaa; Bubb, Nigel L; Franklin, Paul; Dowling, Adam H; Fleming, Garry J P; Wood, David J

    2017-04-01

    To investigate the fundamental wear mechanisms of six resin-based composite (RBC) formulations during short-term in vitro wear testing. RBC materials were condensed into rectangular bar-shaped specimens and light irradiated using the ISO 4049 specimen manufacture and irradiation protocol. Wear testing (n=10 specimens for each RBC) was performed on a modified pin-on-plate wear test apparatus and wear facets were analysed for wear volume loss using a white light profilometer. The wear tested RBC specimens and their corresponding antagonists were analysed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively to determine the wear mechanism. Data generated using the profilometer showed variations in the mean total wear volume (mm 3 ) between the RBCs tested (ptribology of the system rather than relying on a simple wear ranking for the RBC materials as is routinely the case in dental research studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Experimental determination of thermodynamic equilibrium in biocatalytic transamination

    DEFF Research Database (Denmark)

    Tufvesson, Pär; Jensen, Jacob Skibsted; Kroutil, Wolfgang

    2012-01-01

    The equilibrium constant is a critical parameter for making rational design choices in biocatalytic transamination for the synthesis of chiral amines. However, very few reports are available in the scientific literature determining the equilibrium constant (K) for the transamination of ketones....... Various methods for determining (or estimating) equilibrium have previously been suggested, both experimental as well as computational (based on group contribution methods). However, none of these were found suitable for determining the equilibrium constant for the transamination of ketones. Therefore...

  9. A genetic meta-algorithm-assisted inversion approach: hydrogeological study for the determination of volumetric rock properties and matrix and fluid parameters in unsaturated formations

    Science.gov (United States)

    Szabó, Norbert Péter

    2018-03-01

    An evolutionary inversion approach is suggested for the interpretation of nuclear and resistivity logs measured by direct-push tools in shallow unsaturated sediments. The efficiency of formation evaluation is improved by estimating simultaneously (1) the petrophysical properties that vary rapidly along a drill hole with depth and (2) the zone parameters that can be treated as constant, in one inversion procedure. In the workflow, the fractional volumes of water, air, matrix and clay are estimated in adjacent depths by linearized inversion, whereas the clay and matrix properties are updated using a float-encoded genetic meta-algorithm. The proposed inversion method provides an objective estimate of the zone parameters that appear in the tool response equations applied to solve the forward problem, which can significantly increase the reliability of the petrophysical model as opposed to setting these parameters arbitrarily. The global optimization meta-algorithm not only assures the best fit between the measured and calculated data but also gives a reliable solution, practically independent of the initial model, as laboratory data are unnecessary in the inversion procedure. The feasibility test uses engineering geophysical sounding logs observed in an unsaturated loessy-sandy formation in Hungary. The multi-borehole extension of the inversion technique is developed to determine the petrophysical properties and their estimation errors along a profile of drill holes. The genetic meta-algorithmic inversion method is recommended for hydrogeophysical logging applications of various kinds to automatically extract the volumetric ratios of rock and fluid constituents as well as the most important zone parameters in a reliable inversion procedure.

  10. Volumetric Combustion Diagnostics

    Science.gov (United States)

    2017-01-03

    Force Office of Scientific Research Submitted by: Lin Ma, PhD Professor Department of Aerospace and Ocean Engineering Department of Mechanical ...established PLIF (planar LIF [11, 12]) to volumetric measurement of species concentration, and have demonstrated single- shot VLIF measurements in both...Ikeda, J., Xu, W., Carter, C.D. Single Shot 3D Flame Diagnostic Based on Volumetric Laser Induced Fluorescence (VLIF), Proceedings of the

  11. Understanding Volumetric and Gravimetric Hydrogen Adsorption Trade-off in Metal-Organic Frameworks.

    Science.gov (United States)

    Gómez-Gualdrón, Diego A; Wang, Timothy C; García-Holley, Paula; Sawelewa, Ruth M; Argueta, Edwin; Snurr, Randall Q; Hupp, Joseph T; Yildirim, Taner; Farha, Omar K

    2017-10-04

    Metal-organic frameworks (MOFs) are porous crystalline materials that are promising for adsorption-based, on-board storage of hydrogen in fuel-cell vehicles. Volumetric and gravimetric hydrogen capacities are the key factors that determine the size and weight of the MOF-filled tank required to store a certain amount of hydrogen for reasonable driving range. Therefore, they must be optimized so the tank is neither too large nor too heavy. Because the goals of maximizing MOF volumetric and gravimetric hydrogen adsorption loadings individually are incompatible, an in-depth understanding of the trade-off between MOF volumetric and gravimetric loadings is necessary to achieve the best compromise between these properties. Here we study, both experimentally and computationally, the trade-off between volumetric and gravimetric cryo-adsorbed hydrogen deliverable capacity by taking an isoreticular series of highly stable zirconium MOFs, NU-1101, NU-1102, and NU-1103 as a case study. These MOFs were studied under recently proposed operating conditions: 77 K/100 bar →160 K/5 bar. We found the difference between highest and lowest measured deliverable capacity in the MOF series to be ca. 40% gravimetrically, but only ca. 10% volumetrically. From our molecular simulation results, we found hydrogen "monolayer" adsorption to be proportional to the surface area, whereas hydrogen "pore filling" adsorption is proportional to the pore volume. Thus, we found that the higher variability in gravimetric deliverable capacity in contrast to the volumetric capacity, occurs due to the proportional relation between gravimetric surface area and pore volume in the NU-110x series in contrast to the inverse relation between volumetric surface area and void fraction. Additionally, we find better correlations with geometric surface areas than with BET areas. NU-1101 presents the highest measured volumetric performance with 46.6 g/L (9.1 wt %), whereas NU-1103 presents the highest gravimetric one

  12. Experimental Determination of Gas Phase Thermodynamic Properties of Bimolecular Complexes

    Science.gov (United States)

    Hansen, Anne S.; Maroun, Zeina; Mackeprang, Kasper; Kjaergaard, Henrik G.

    2016-06-01

    Accurate determination of the atmospheric abundance of hydrogen bound bimolecular complexes is necessary, as hydrogen bonds are partly responsible for the formation and growth of aerosol particles. The abundance of a complex is related to the Gibbs free energy of complex formation (Δ G), which is often obtained from quantum chemical calculations that rely on calculated values of the enthalpy (Δ H) and entropy (Δ S) of complex formation. However, calculations of Δ H and in particular Δ S are associated with large uncertainties, and accurate experimental values are therefore crucial for theoretical benchmarking studies. Infrared measurements of gas phase hydrogen bound complexes were performed in the 300 to 373 K range, and lead to a purely experimental determination of Δ H using the van't Hoff equation. Equilibrium constants were determined by combining an experimental and calculated OH-stretching intensity, from which values of Δ G and hence Δ S could be determined. Thus we can determine Δ G, Δ H and Δ S for a bimolecular complex. We find that in the 300 to 373 K temperature range the determined Δ H and Δ S values are independent of temperature.

  13. Numerical and experimental determination of surface temperature and moisture evolution in a field soil

    Science.gov (United States)

    Akinyemi, Olukayode D.; Mendes, Nathan

    2007-03-01

    Knowledge about the dynamics of soil moisture and heat, especially at the surface, provides important insights into the physical processes governing their interactions with the atmosphere, thereby improving the understanding of patterns of climate dynamics. In this context the paper presents the numerical and field experimental results of temperature and moisture evolution, which were measured on the surface of a sandy soil at Abeokuta, south-western Nigeria. An unconditionally stable numerical method was used, which linearizes the vapour concentration driving-potential term giving the moisture exchanged at the boundaries in terms of temperature and moisture content, and simultaneously solves the governing equations for each time step. The model avoids stability problems and limitations to low moisture contents and the usual assumption of constant thermal conductivity. Instantaneous temperature measurements were made at the surface using a thermocouple, while the gravimetric method was employed to determine the volumetric water contents at some specific hours of the experimental period. The observed experimental data compared fairly well with the predicted values, with both having correlation coefficients greater than 0.9 and consequently following a common diurnal trend. The sensitivity of the model was very high to the choice of simulation parameters, especially grid size refinement and time step. While the model underestimated the soil moisture content at 6 a.m. and 10 p.m., the measured temperatures were however overestimated. When compared to moisture content, average errors for temperature were low resulting in a minimal absolute difference in amplitude of 0.81 °C.

  14. Experimental determination of the degree of polarization of quantum states

    DEFF Research Database (Denmark)

    Kothe-Termén, Christian; Madsen, Lars Skovgaard; Andersen, Ulrik Lund

    2013-01-01

    We demonstrate experimental excitation-manifold-resolved polarization characterization of quantum states of light ranging from the few-photon to the many-photon level. In contrast to the traditional characterization of polarization that is based on the Stokes parameters, we experimentally determine...... the Stokes vector of each excitation manifold separately. Only for states with a given photon number do the methods coincide. For states with an indeterminate photon number, for example Gaussian states, the employed method gives a richer and more accurate description. We apply the method both in theory...

  15. Experimental determination of satellite bolted joints thermal resistance

    Science.gov (United States)

    Mantelli, Marcia Barbosa Henriques; Basto, Jose Edson

    1990-01-01

    The thermal resistance was experimentally determined of the bolted joints of the first Brazilian satellite (SCD 01). These joints, used to connect the satellite structural panels, are reproduced in an experimental apparatus, keeping, as much as possible, the actual dimensions and materials. A controlled amount of heat is forced to pass through the joint and the difference of temperature between the panels is measured. The tests are conducted in a vacuum chamber with liquid nitrogen cooled walls, that simulates the space environment. Experimental procedures are used to avoid much heat losses, which are carefully calculated. Important observations about the behavior of the joint thermal resistance with the variation of the mean temperature are made.

  16. Delay Discounting of Self-Determined and Experimenter-Determined Commodities

    Science.gov (United States)

    Weatherly, Jeffrey N.; Gudding, Jennifer; Derenne, Adam

    2010-01-01

    Research suggests that individuals prefer self-determined reinforcers over experimenter-determined ones. The present study had 518 college students complete a delay-discounting task in which the commodity was cigarettes, a grocery store gift card, casino tokens, cash, or the choice of the four. The least amount of delay discounting was observed…

  17. Experimental Determination of Hydraulic Properties of Unsaturated Calcarenites

    Science.gov (United States)

    Turturro, Antonietta Celeste; Andriani, Gioacchino Francesco; Clementina Caputo, Maria; Maggi, Sabino

    2013-04-01

    Understanding hydraulic properties is essential in the modeling of flow and solute transport through the vadose zone, to which problems of soil and groundwater pollution are related. The vadose zone, in fact, is of great importance in controlling groundwater recharge and transport of contaminants into and through the subsoil. The aim of this work is to determine experimentally in laboratory the hydraulic properties of unsaturated calcarenites using an approach including petrophysical determinations and methods for measuring water retention. For this purpose, samples of calcarenites belonging to the Calcarenite di Gravina Fm.(Pliocene-early Pleistocene), came from two different quarry districts located in Southern Italy (Canosa di Puglia and Massafra), were utilized. The water retention function, θ(h), which binds the water content, θ, to water potential, h, was determined in the laboratory by means two different experimental methods: the WP4-T psychrometer and the suction table. At last, a simple mathematical equation represented by van Genuchten's model is fitted to the experimental data and the unknown empirical parameters of this model are determined. Textural analysis on thin sections using optical petrographic microscopy and evaluation of total and effective porosity by means of standard geotechnical laboratory tests, mercury intrusion porosimetry and image analysis were also performed. In particular, a comparison between mercury porosimetry data and results of photomicrograph computer analysis through the methods of quantitative stereology was employed for providing pore size distributions. The results of this study identify the relationship between the hydraulic behavior, described by the water retention function, and pore size distribution for the calcarenites that are not easy to hydraulically characterize. This relationship could represent a useful tool to infer the unsaturated hydraulic properties of calcarenites and in general this approach could be

  18. Process conditions and volumetric composition in composites

    DEFF Research Database (Denmark)

    Madsen, Bo

    2013-01-01

    The obtainable volumetric composition in composites is linked to the gravimetric composition, and it is influenced by the conditions of the manufacturing process. A model for the volumetric composition is presented, where the volume fractions of fibers, matrix and porosity are calculated...... as a function of the fiber weight fraction, and where parameters are included for the composite microstructure, and the fiber assembly compaction behavior. Based on experimental data of composites manufactured with different process conditions, together with model predictions, different types of process related...... the fiber and matrix volume fractions are only slightly changed. Air entrapment in the matrix due to non-ideal process conditions is found to have a marked effect on the volumetric composition. For composites with such type of matrix porosity, the porosity content is decreased when the fiber content...

  19. Volumetric composition in composites and historical data

    DEFF Research Database (Denmark)

    Lilholt, Hans; Madsen, Bo

    2013-01-01

    The obtainable volumetric composition in composites is of importance for the prediction of mechanical and physical properties, and in particular to assess the best possible (normally the highest) values for these properties. The volumetric model for the composition of (fibrous) composites gives...... guidance to the optimal combination of fibre content, matrix content and porosity content, in order to achieve the best obtainable properties. Several composite materials systems have been shown to be handleable with this model. An extensive series of experimental data for the system of cellulose fibres...... and polymer (resin) was produced in 1942 – 1944, and these data have been (re-)analysed by the volumetric composition model, and the property values for density, stiffness and strength have been evaluated. Good agreement has been obtained and some further observations have been extracted from the analysis....

  20. Quantitative Determination of Isotope Ratios from Experimental Isotopic Distributions

    Science.gov (United States)

    Kaur, Parminder; O’Connor, Peter B.

    2008-01-01

    Isotope variability due to natural processes provides important information for studying a variety of complex natural phenomena from the origins of a particular sample to the traces of biochemical reaction mechanisms. These measurements require high-precision determination of isotope ratios of a particular element involved. Isotope Ratio Mass Spectrometers (IRMS) are widely employed tools for such a high-precision analysis, which have some limitations. This work aims at overcoming the limitations inherent to IRMS by estimating the elemental isotopic abundance from the experimental isotopic distribution. In particular, a computational method has been derived which allows the calculation of 13C/12C ratios from the whole isotopic distributions, given certain caveats, and these calculations are applied to several cases to demonstrate their utility. The limitations of the method in terms of the required number of ions and S/N ratio are discussed. For high-precision estimates of the isotope ratios, this method requires very precise measurement of the experimental isotopic distribution abundances, free from any artifacts introduced by noise, sample heterogeneity, or other experimental sources. PMID:17263354

  1. Determination of solubility profiles of eflucimibe polymorphs: experimental and modeling.

    Science.gov (United States)

    Teychene, S; Autret, J M; Biscans, B

    2006-04-01

    This work presents the determination of the phase diagram of two polymorphs of Eflucimibe in pure solvents and solvent mixtures at different temperatures. Solid phase changes were analysed by Differential Scanning Calorimetry. Solubility measurements show that the solubility of the two forms are very similar. Experimental data obtained in ethanol, reported in a Van t'Hoff plot, exhibit a transition temperature around 265 K. A single maximum is observed when solubility is plotted against the solubility parameters of solvents or solvent mixture and it is not related to a solid phase change. This phenomenon, known as a positive synergetic effect, has been explained in term of evolution of solute-solvents polar interactions. Several thermodynamics models (UNIFAC, UNIQUAC, Wilson, Scatchard Hildebrand ... ) were tested in order to predict the Liquid-Solid Equilibrium for this system. The semi empirical model UNIQUAC gives the best fit. The results obtained are in good agreement with the experimental data (mean deviation lower than 5%) and the solubility maximum found experimentally for each polymorph is also well described.

  2. Experimental determination of monoethanolamine protonation constant and its temperature dependency

    Directory of Open Access Journals (Sweden)

    Ma’mun Sholeh

    2017-01-01

    Full Text Available Carbon dioxide as one of the major contributors to the global warming problem is produced in large quantities by many important industries and its emission seems to rise from year to year. Aminebased absorption is one of the methods to capture CO2 from its sources. As a reactive system, mass transfer and chemical reaction take place simultaneously. In a vapor-liquid equilibrium model for the CO2-amine-water system, some parameters such as mass transfer coefficients and chemical equilibrium constants need to be known. However, some parameters could be determined experimentally and the rests could be regressed from the model. The protonation constant (pKa, as one of the model parameters, could then be measured experimentally. The purpose of this study is to measure the pKa of monoethanolamine (MEA at a range of temperatures from 303 to 330K by a potentiometric titration method. The experimental data obtained were in a good agreement with the literature data. The pKa data from this work together with those from the literature were then correlated in an empirical correlation to be used for future research.

  3. Direct experimental determination of the atomic structure at internal interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Browning, N.D. [Oak Ridge National Lab., TN (United States)]|[Illinois Univ., Chicago, IL (United States); Pennycook, S.J. [Oak Ridge National Lab., TN (United States)

    1995-07-01

    A crucial first step in understanding the effect that internal interfaces have on the properties of materials is the ability to determine the atomic structure at the interface. As interfaces can contain atomic disorder, dislocations, segregated impurities and interphases, sensitivity to all of these features is essential for complete experimental characterization. By combining Z-contrast imaging and electron energy loss spectroscopy (EELS) in a dedicated scanning transmission electron microscope (STEM), the ability to probe the structure, bonding and composition at interfaces with the necessary atomic resolution has been obtained. Experimental conditions can be controlled to provide, simultaneously, both incoherent imaging and spectroscopy. This enables interface structures observed in the image to be interpreted intuitively and the bonding in a specified atomic column to be probed directly by EELS. The bonding and structure information can then be correlated using bond-valence sum analysis to produce structural models. This technique is demonstrated for 25{degrees}, 36{degrees} and 67{degrees} symmetric and 45{degrees} and 25{degrees} asymmetric [001] tilt grain boundaries in SrTiO{sub 3} The structures of both types of boundary were found to contain partially occupied columns in the boundary plane. From these experimental results, a series of structural units were identified which could be combined, using continuity of gain boundary structure principles, to construct all [001] tilt boundaries in SrTiO{sub 3}. Using these models, the ability of this technique to address the issues of vacancies and dopant segregation at grain boundaries in electroceramics is discussed.

  4. Experimental determination of plate parameters with an air coupled instrument

    International Nuclear Information System (INIS)

    El Mouhtadi, Abdelhak; Duclos, Jean; Duflo, Hugues

    2011-01-01

    The present work deals with an experimental determination of acoustical properties of a viscoelastic homogeneous plate using an air coupled equipment. Usually, these properties are determined separately through several measurements, while our paper provides a quick inverse method which permits to measure them simultaneously and requires only the knowledge of the sound velocity in air and its density. The experimental transmission through a face parallel plate, at normal incidence, is investigated and compared with the theoretically predicted one. Measurements are conducted using a chirp signal having 1.2 MHz central frequency with 800 kHz bandwidth and 100 μs duration. Two signals are being exploited : one only through air path and another one through the sample inserted between the transducers. The FFTs of these signals provide the complex transmission coefficient as a function of frequency. The identification of parameters is carried out using the real and imaginary parts of the transmission coefficient. Then, assuming the wave velocity and density of air are known, we deduce the four properties of the plate (thickness, density, longitudinal velocity and attenuation coefficient) as well as the attenuation coefficient of air. A variety of viscoelastic materials, whose impedances have weak values, has been studied such as Polyethylene, Plexiglas and carbon/epoxy composite. The physical properties for each plate are obtained with a good accuracy in the frequency range of investigation.

  5. Treatment Planning and Volumetric Response Assessment for Yttrium-90 Radioembolization: Semiautomated Determination of Liver Volume and Volume of Tumor Necrosis in Patients with Hepatic Malignancy

    International Nuclear Information System (INIS)

    Monsky, Wayne L.; Garza, Armando S.; Kim, Isaac; Loh, Shaun; Lin, Tzu-Chun; Li Chinshang; Fisher, Jerron; Sandhu, Parmbir; Sidhar, Vishal; Chaudhari, Abhijit J.; Lin, Frank; Deutsch, Larry-Stuart; Badawi, Ramsey D.

    2011-01-01

    Purpose: The primary purpose of this study was to demonstrate intraobserver/interobserver reproducibility for novel semiautomated measurements of hepatic volume used for Yttrium-90 dose calculations as well as whole-liver and necrotic-liver (hypodense/nonenhancing) tumor volume after radioembolization. The secondary aim was to provide initial comparisons of tumor volumetric measurements with linear measurements, as defined by Response Evaluation Criteria in Solid Tumors criteria, and survival outcomes. Methods: Between 2006 and 2009, 23 consecutive radioembolization procedures were performed for 14 cases of hepatocellular carcinoma and 9 cases of hepatic metastases. Baseline and follow-up computed tomography obtained 1 month after treatment were retrospectively analyzed. Three observers measured liver, whole-tumor, and tumor-necrosis volumes twice using semiautomated software. Results: Good intraobserver/interobserver reproducibility was demonstrated (intraclass correlation [ICC] > 0.9) for tumor and liver volumes. Semiautomated measurements of liver volumes were statistically similar to those obtained with manual tracing (ICC = 0.868), but they required significantly less time to perform (p 0.05). Dose, change in tumor diameters, tumor volume, and necrotic volume did not correlate with survival (p > 0.05 in all instances). However, Kaplan–Meier curves suggest that a >10% increase in necrotic volume correlated with survival (p = 0.0472). Conclusion: Semiautomated volumetric analysis of liver, whole-tumor, and tumor-necrosis volume can be performed with good intraobserver/interobserver reproducibility. In this small retrospective study, measurements of tumor necrosis were suggested to correlate with survival.

  6. A projection method for under determined optimal experimental designs

    KAUST Repository

    Long, Quan

    2014-01-09

    A new implementation, based on the Laplace approximation, was developed in (Long, Scavino, Tempone, & Wang 2013) to accelerate the estimation of the post–experimental expected information gains in the model parameters and predictive quantities of interest. A closed–form approximation of the inner integral and the order of the corresponding dominant error term were obtained in the cases where the parameters are determined by the experiment. In this work, we extend that method to the general cases where the model parameters could not be determined completely by the data from the proposed experiments. We carry out the Laplace approximations in the directions orthogonal to the null space of the corresponding Jacobian matrix, so that the information gain (Kullback–Leibler divergence) can be reduced to an integration against the marginal density of the transformed parameters which are not determined by the experiments. Furthermore, the expected information gain can be approximated by an integration over the prior, where the integrand is a function of the projected posterior covariance matrix. To deal with the issue of dimensionality in a complex problem, we use Monte Carlo sampling or sparse quadratures for the integration over the prior probability density function, depending on the regularity of the integrand function. We demonstrate the accuracy, efficiency and robustness of the proposed method via several nonlinear under determined numerical examples.

  7. Antioxidant Capacity: Experimental Determination by EPR Spectroscopy and Mathematical Modeling.

    Science.gov (United States)

    Polak, Justyna; Bartoszek, Mariola; Chorążewski, Mirosław

    2015-07-22

    A new method of determining antioxidant capacity based on a mathematical model is presented in this paper. The model was fitted to 1000 data points of electron paramagnetic resonance (EPR) spectroscopy measurements of various food product samples such as tea, wine, juice, and herbs with Trolox equivalent antioxidant capacity (TEAC) values from 20 to 2000 μmol TE/100 mL. The proposed mathematical equation allows for a determination of TEAC of food products based on a single EPR spectroscopy measurement. The model was tested on the basis of 80 EPR spectroscopy measurements of herbs, tea, coffee, and juice samples. The proposed model works for both strong and weak antioxidants (TEAC values from 21 to 2347 μmol TE/100 mL). The determination coefficient between TEAC values obtained experimentally and TEAC values calculated with proposed mathematical equation was found to be R(2) = 0.98. Therefore, the proposed new method of TEAC determination based on a mathematical model is a good alternative to the standard EPR method due to its being fast, accurate, inexpensive, and simple to perform.

  8. Experimental determination of soot refractive index in the infrared

    International Nuclear Information System (INIS)

    Ouf, F.X.; Vendel, J.; Ouf, F.X.; Coppalle, A.; Weil, M.E.; Yon, J.

    2007-01-01

    The study of physical properties of soot particles produced during combustion is a complex subject but of a great interest within the framework of the study of the safety of an installation, with respect to the fire hazard. These characteristics are, in this case, particularly useful in order to predict the behaviour of containment barriers in situation of fire, but also in order to estimate the contribution of these particles to radiative transfers. The aim of this study is to determine the radiative properties of soot particles produced during combustion. A specific device, which establishes extinction and vertical-vertical scattering coefficients, has been developed and has allowed to determine the refractive index of soot particles in the infrared. This determination also needed the establishment of size distribution and morphological properties of soot aggregates. We present in this document the experimental device developed, and the validation of this device on latex spheres which optical properties are well known. First results of extinction coefficients will be presented and will underline the similar optical behaviour of different soot aggregates. Values of refractive index will be detailed and discussed, and a direct application of these values will be carried out in order to determine the soot volume fraction. A comparison with reference method will underline the efficiency of our method. We will conclude on the validity of the information brought by this device and on the prospects of this study. A discussion is included, on the utility of mean values of refractive index and on the determination of total emissivity of soot particles. (authors)

  9. A review of experimental methods for determining residual creep life

    International Nuclear Information System (INIS)

    Bolton, C.J.

    1977-11-01

    Experimental methods available for determining how much creep life remains at a particular time in the high temperature service of a component are reviewed. After a brief consideration of the limitations of stress rupture extrapolation techniques, the application of post-exposure creep testing is considered. Ways of assessing the effect of microstructural degradation on residual life are then reviewed. It is pointed out that while this type of work will be useful for certain materials, there are other materials in which 'mechanical damage' such as cavitation will be more important. Cavitation measurement techniques are therefore reviewed. The report ends with a brief consideration of the use of crack growth measurements in assessing the residual life of cracked components. (author)

  10. Recent Experimental Advances to Determine (noble) Gases in Waters

    Science.gov (United States)

    Kipfer, R.; Brennwald, M. S.; Huxol, S.; Mächler, L.; Maden, C.; Vogel, N.; Tomonaga, Y.

    2013-12-01

    In aquatic systems noble gases, radon, and bio-geochemically conservative transient trace gases (SF6, CFCs) are frequently applied to determine water residence times and to reconstruct past environmental and climatic conditions. Recent experimental breakthroughs now enable ● to apply the well-established concepts of terrestrial noble gas geochemistry in waters to the minute water amounts stored in sediment pore space and in fluid inclusions (A), ● to determine gas exchange processes on the bio-geochemical relevant time scales of minutes - hours (B), and ● to separate diffusive and advective gas transport in soil air (C). A. Noble-gas analysis in water samples (doi:10:4319/lom.2011.9.42. [2] Vogel et al. (2013) Geochem. Geophys. Geosyst., 14, doi:10.1002/ggge.20164. [3] Brennwald et al. (2013) Environ. Sci. Technol., Article ASAP, DOI: 10.1021/es401698p. [4] Mächler et al. (2012) Environ. Sci. Technol., 47, 7060-7066. [5] Huxol et al. Environ. Sci. Technol., in revision.

  11. Effect of consolidation pressure on volumetric composition and stiffness of unidirectional flax fibre composites

    DEFF Research Database (Denmark)

    Aslan, Mustafa; Mehmood, S.; Madsen, Bo

    2013-01-01

    Unidirectional flax/polyethylene terephthalate composites are manufactured by filament winding, followed by compression moulding with low and high consolidation pressure, and with variable flax fibre content. The experimental data of volumetric composition and tensile stiffness are analysed...... assemblies. A characteristic microstructural feature is observed near the transition stage, the so-called local structural porosity, which is caused by the locally fully compacted fibres. At the transition fibre weight fraction, which determines the best possible combination of high fibre volume fraction...

  12. Modeling and Experimental Validation of a Volumetric Expander Suitable for Waste Heat Recovery from an Automotive Internal Combustion Engine Using an Organic Rankine Cycle with Ethanol

    Directory of Open Access Journals (Sweden)

    José Galindo

    2016-04-01

    Full Text Available Waste heat recovery (WHR in exhaust gas flow of automotive engines has proved to be a useful path to increase the overall efficiency of internal combustion engines (ICE. Recovery potentials of up to 7% are shown in several works in the literature. However, most of them are theoretical estimations. Some present results from prototypes fed by steady flows generated in an auxiliary gas tank and not with actual engine exhaust gases. This paper deals with the modeling and experimental validation of an organic Rankine cycle (ORC with a swash-plate expander integrated in a 2 L turbocharged petrol engine using ethanol as working fluid. A global simulation model of the ORC was developed with a maximum difference of 5%, validated with experimental results. Considering the swash-plate as the main limiting factor, an additional specific submodel was implemented to model the physical phenomena in this element. This model allows simulating the fluid dynamic behavior of the swash-plate expander using a 0D model (Amesim. Differences up to 10.5% between tests and model results were found.

  13. Flexible Volumetric Structure

    Science.gov (United States)

    Cagle, Christopher M. (Inventor); Schlecht, Robin W. (Inventor)

    2014-01-01

    A flexible volumetric structure has a first spring that defines a three-dimensional volume and includes a serpentine structure elongatable and compressible along a length thereof. A second spring is coupled to at least one outboard edge region of the first spring. The second spring is a sheet-like structure capable of elongation along an in-plane dimension thereof. The second spring is oriented such that its in-plane dimension is aligned with the length of the first spring's serpentine structure.

  14. Uncertainty quantification in volumetric Particle Image Velocimetry

    Science.gov (United States)

    Bhattacharya, Sayantan; Charonko, John; Vlachos, Pavlos

    2016-11-01

    Particle Image Velocimetry (PIV) uncertainty quantification is challenging due to coupled sources of elemental uncertainty and complex data reduction procedures in the measurement chain. Recent developments in this field have led to uncertainty estimation methods for planar PIV. However, no framework exists for three-dimensional volumetric PIV. In volumetric PIV the measurement uncertainty is a function of reconstructed three-dimensional particle location that in turn is very sensitive to the accuracy of the calibration mapping function. Furthermore, the iterative correction to the camera mapping function using triangulated particle locations in space (volumetric self-calibration) has its own associated uncertainty due to image noise and ghost particle reconstructions. Here we first quantify the uncertainty in the triangulated particle position which is a function of particle detection and mapping function uncertainty. The location uncertainty is then combined with the three-dimensional cross-correlation uncertainty that is estimated as an extension of the 2D PIV uncertainty framework. Finally the overall measurement uncertainty is quantified using an uncertainty propagation equation. The framework is tested with both simulated and experimental cases. For the simulated cases the variation of estimated uncertainty with the elemental volumetric PIV error sources are also evaluated. The results show reasonable prediction of standard uncertainty with good coverage.

  15. Experimental determination of residence time distribution in continuous dry granulation.

    Science.gov (United States)

    Mangal, Haress; Kleinebudde, Peter

    2017-05-30

    With increasing importance of continuous manufacturing, the interest in integrating dry granulation into a continuous manufacturing line is growing. Residence time distribution measurements are of importance as they provide information about duration of materials within the process. These data enable traceability and are highly beneficial for developing control strategies. A digital image analysis system was used to determine the residence time distribution of two materials with different deformation behavior (brittle, plastic) in the milling unit of dry granulation systems. A colorant was added to the material (20%w/w iron oxide), which did not affect the material properties excessively, so the milling process could be mimicked well. Experimental designs were conducted to figure out which parameters effect the mean residence time strongly. Moreover, two types of dry granulation systems were contrasted. Longer mean residence times were obtained for the oscillating mill (OM) compared to the conical mill (CM). For co-processed microcrystalline cellulose residence times of 19.8-44.4s (OM) and 11.6-29.1s (CM) were measured, mainly influenced by the specific compaction force, the mill speed and roll speed. For dibasic calcium phosphate anhydrate residence times from 17.7-46.4 (OM) and 5.4-10.2s (CM) were measured, while here the specific compaction force, the mill speed and their interactions with the roll speed had an influence on the mean residence time. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Experimental determinations of the performances of heat transfer surfaces

    International Nuclear Information System (INIS)

    Pirovano, Alain; Viannay, Stephane; Mazeas, C.Y.

    1974-01-01

    With the help of flow schemes and of assumptions on the heat transfer, it is possible, in some cases, to predict the thermal and aerodynamical performances of a new heat transfer surface with moderate accuracy. These estimates, valid for an approximate classification of a new surface among known surfaces, are not accurate enough to be taken as a basis for the design of heat exchangers. In the present state of knowledge, the performances of a new heat transfer surface can only be determined accurately with experimental measurements. Bertin and Co have at their disposal two air test rigs especially designed for this purpose. The first one, more directly concerned with the measurements on tube bundles with fluid flow perpendicular to the generatrices of the tubes, is a semi-closed loop equipped with a high-efficiency ejector which amplifies the air flow rate supplied by an external source and thus allows high values of Reynolds number to be reached. The second one is adapted to other types of surfaces: tubes with external flow parallel to the generatrices, tubes with sophisticated cross section and with internal flow, compact surfaces with finned plates, etc. Both test rigs, the relevant equipment, the methods of data acquisition and of test results analysis are described in this paper. During the 5 past years, 60 configurations were tested. It was possible to compare some of the test results with the results of measurements performed later, on entire heat exchangers working with numbers of tubes, fluids, and temperature levels different from those prevailing during the tests on the small scale mock-up; the agreement is quite good [fr

  17. CCDC 1416891: Experimental Crystal Structure Determination : Methyl-triphenyl-germanium

    KAUST Repository

    Bernatowicz, Piotr

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  18. CCDC 1408042: Experimental Crystal Structure Determination : 6,13-dimesitylpentacene

    KAUST Repository

    Shi, Xueliang

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  19. Plant fibre composites - porosity and volumetric interaction

    DEFF Research Database (Denmark)

    Madsen, Bo; Thygesen, Anders; Lilholt, Hans

    2007-01-01

    the combination of a high fibre volume fraction, a low porosity and a high composite density is optimal. Experimental data from the literature on volumetric composition and density of four types of plant fibre composites are used to validate the model. It is demonstrated that the model provides a concept......Plant fibre composites contain typically a relative large amount of porosity, which considerably influences properties and performance of the composites. The large porosity must be integrated in the conversion of weight fractions into volume fractions of the fibre and matrix parts. A model...... is presented to predict the porosity as a function of the fibre weight fractions, and to calculate the related fibre and matrix volume fractions, as well as the density of the composite. The model predicts two cases of composite volumetric interaction separated by a transition fibre weight fraction, at which...

  20. Calculation procedure to determine average mass transfer coefficients in packed columns from experimental data for ammonia-water absorption refrigeration systems

    Energy Technology Data Exchange (ETDEWEB)

    Sieres, Jaime; Fernandez-Seara, Jose [University of Vigo, Area de Maquinas y Motores Termicos, E.T.S. de Ingenieros Industriales, Vigo (Spain)

    2008-08-15

    The ammonia purification process is critical in ammonia-water absorption refrigeration systems. In this paper, a detailed and a simplified analytical model are presented to characterize the performance of the ammonia rectification process in packed columns. The detailed model is based on mass and energy balances and simultaneous heat and mass transfer equations. The simplified model is derived and compared with the detailed model. The range of applicability of the simplified model is determined. A calculation procedure based on the simplified model is developed to determine the volumetric mass transfer coefficients in the vapour phase from experimental data. Finally, the proposed model and other simple calculation methods found in the general literature are compared. (orig.)

  1. Hyperspectral image classification based on volumetric texture and dimensionality reduction

    Science.gov (United States)

    Su, Hongjun; Sheng, Yehua; Du, Peijun; Chen, Chen; Liu, Kui

    2015-06-01

    A novel approach using volumetric texture and reduced-spectral features is presented for hyperspectral image classification. Using this approach, the volumetric textural features were extracted by volumetric gray-level co-occurrence matrices (VGLCM). The spectral features were extracted by minimum estimated abundance covariance (MEAC) and linear prediction (LP)-based band selection, and a semi-supervised k-means (SKM) clustering method with deleting the worst cluster (SKMd) bandclustering algorithms. Moreover, four feature combination schemes were designed for hyperspectral image classification by using spectral and textural features. It has been proven that the proposed method using VGLCM outperforms the gray-level co-occurrence matrices (GLCM) method, and the experimental results indicate that the combination of spectral information with volumetric textural features leads to an improved classification performance in hyperspectral imagery.

  2. Experimental evidence for suspence as determinant of video game enjoyment

    NARCIS (Netherlands)

    Klimmt, C.; Rizzo, A.; Vorderer, P.A.; Koch, J.; Fischer, T.

    2009-01-01

    Based on theoretical assumptions from film psychology and their application to video games, the hypothesis is tested that suspense is a major factor in video game enjoyment. A first-person shooter game was experimentally manipulated to create either a low level or a high level of suspense.

  3. Experimental bifurcation analysis of an impact oscillator – Determining stability

    DEFF Research Database (Denmark)

    Bureau, Emil; Schilder, Frank; Elmegård, Michael

    2014-01-01

    We propose and investigate three different methods for assessing stability of dynamical equilibrium states during experimental bifurcation analysis, using a control-based continuation method. The idea is to modify or turn off the control at an equilibrium state and study the resulting behavior...

  4. Experimental Determination of Some Thermal Properties of Raphia ...

    African Journals Online (AJOL)

    The thermal properties - thermal conductivity, specific heat capacity and viscosity of raphia gum are studied experimentally. The results show that thermal conductivity varies from 0.0164 to 0.0403 (W/mok) for moisture content and temperature ranging from 59.77 to 93.13% (W.b) and 40 to 80 (oC) respectively. The specific ...

  5. Experimental determination of the heterotroph anoxic yield in anoxic ...

    African Journals Online (AJOL)

    This paper describes experimental research to directly quantify the ordinary heterotrophic organism (OHO) cell yield coefficient under anoxic and aerobic conditions with real wastewater as substrate. Until recently these two values were assumed equal in activated sludge models, despite theoretical predictions that the ...

  6. Volumetric velocimetry for fluid flows

    Science.gov (United States)

    Discetti, Stefano; Coletti, Filippo

    2018-04-01

    In recent years, several techniques have been introduced that are capable of extracting 3D three-component velocity fields in fluid flows. Fast-paced developments in both hardware and processing algorithms have generated a diverse set of methods, with a growing range of applications in flow diagnostics. This has been further enriched by the increasingly marked trend of hybridization, in which the differences between techniques are fading. In this review, we carry out a survey of the prominent methods, including optical techniques and approaches based on medical imaging. An overview of each is given with an example of an application from the literature, while focusing on their respective strengths and challenges. A framework for the evaluation of velocimetry performance in terms of dynamic spatial range is discussed, along with technological trends and emerging strategies to exploit 3D data. While critical challenges still exist, these observations highlight how volumetric techniques are transforming experimental fluid mechanics, and that the possibilities they offer have just begun to be explored.

  7. Experimental determination of the slow-neutron wavelength distribution

    DEFF Research Database (Denmark)

    Lebech, Bente; Mikke, K.; Sledziewska-Blocka, D.

    1970-01-01

    Different experiments for determining the slow-neutron wavelength distribution in the region 227-3 meV have been carried out, and the results compared. It is concluded that the slow-neutron wave-length distribution can be determined accurately by elastic scattering on a pure incoherent or a pure ...

  8. Experimental determination of tritium oxidation speed in atmosphere

    International Nuclear Information System (INIS)

    Clerc, H.; Calando, J.P.; Paillard, P.; Gros, R.; Hircq, B.

    1988-01-01

    In the framework of fusion reactor safety studies it is necessary to know the kinetics of gaseous tritium oxidation. Literature differences have conducted the European Communities to realize a research program in case of tritium release for a rapid accidental release and for a slow routine release. This report gives the experimental conditions and the results of rapid accidental release. Experiments have been done at Bruyeres-le-Chatel (FR) with a 40 meters chimney [fr

  9. Experimental determination of useful resistance value during pasta dough kneading

    Science.gov (United States)

    Podgornyj, Yu I.; Martynova, T. G.; Skeeba, V. Yu; Kosilov, A. S.; Chernysheva, A. A.; Skeeba, P. Yu

    2017-10-01

    There is a large quantity of materials produced in the form of dry powder or low humidity granulated masses in the modern market, and there is a need to develop new manufacturing machinery and to renew the existing facilities involved in the production of various loose mixtures. One of the machinery upgrading tasks is enhancing its performance. In view of the fact that experimental research is not feasible in full-scale samples, an experimental installation was to be constructed. The article contains its kinematic scheme and the 3D model. The angle of the kneading blade location, the volume of the loose mixture, rotating frequency and the number of the work member double passes were chosen as variables to carry out the experiment. The technique of the experiment, which includes two stages for the rotary and reciprocating movement of the work member, was proposed. The results of the experimental data processing yield the correlations between the load characteristics of the mixer work member and the angle of the blade, the volume of the mixture and the work member rotating frequency, allowing for the recalculation of loads for this type machines.

  10. Experimental Determination of Thermal Conductivity of Low-Density Ice

    Science.gov (United States)

    Coles, Willard D.

    1954-01-01

    The thermal conductivity of low-density ice has been computed from data obtained in an experimental investigation of the heat transfer and mass transfer by sublimation for an iced surface on a flat plate in a high-velocity tangential air stream. The results are compared with data from several sources on the thermal conductivity of packed snow and solid glaze ice. The results show good agreement with the equations for the thermal conductivity of packed snow as a function of snow density. The agreement of the curves for packed snow near the solid ice regime with the values of thermal conductivity, of ice indicates that the curves are applicable over the entire-ice-density range.

  11. Experimental determination of linear optics including quadrupole rotations

    International Nuclear Information System (INIS)

    Safranek, J.

    1995-01-01

    The measured response matrix giving the change in orbit at beam position monitors (BPMs) with changes in steering magnet excitation can be used to accurately determine many important parameters in a storage ring. Using the NSLS X-Ray Ring measured response matrix we have determined the gradients in all 56 quadrupole magnets; the calibration of the steering magnets and BPMs; the rotational mis-alignments of the quadrupoles, steering magnets, and BPMs about the electron beam direction; the longitudinal magnetic centers of the orbit steering magnets; and the transverse mis-alignments of the sextupoles. Random orbit measurement error of the BPMs propagated to give 0.04% rms error in determination of individual quadrupole gradients and 0.4 mrad rms error in the determination of quadrupole rotational alignment. Small variations of a few parts in a thousand in the quadrupole gradients within an individual family were resolved. The improved understanding of the X-Ray Ring has enabled us to better control the electron beam size

  12. Experimentally determined coordinates for three MILS hydrophones near Ascension Island

    International Nuclear Information System (INIS)

    Harben, P.E.; Hollfelder, J.R.; Rodgers, A.J.

    1999-01-01

    We conducted an airgun survey in the waters of Ascension Island in May 1999 to determine new locations and depths for three Missile Impact Location System (MILS) hydrophones (ASC23, ASC24, and ASC26) currently in use by the Prototype International Data Center (PIDC) and the National Data Center (NDC). The nominal and new locations are summarized. Although not rigorous, errors in the new locations and depths are conservatively estimated to be less than 100 m. The hydrophones are either on or near the ocean bottom in all three cases. The new depths are consistent with the following: Direct-phase airgun arrivals; Bathymetry determined along the track of the ship used for this airgun survey; Reflected phases from the airgun data; Depths given in the original hydrophone installation report. (author)

  13. Experimentally Determined Heat Transfer Coefficients for Spacesuit Liquid Cooled Garments

    Science.gov (United States)

    Bue, Grant; Watts, Carly; Rhodes, Richard; Anchondo, Ian; Westheimer, David; Campbell, Colin; Vonau, Walt; Vogel, Matt; Conger, Bruce

    2015-01-01

    A Human-In-The-Loop (HITL) Portable Life Support System 2.0 (PLSS 2.0) test has been conducted at NASA Johnson Space Center in the PLSS Development Laboratory from October 27, 2014 to December 19, 2014. These closed-loop tests of the PLSS 2.0 system integrated with human subjects in the Mark III Suit at 3.7 psi to 4.3 psi above ambient pressure performing treadmill exercise at various metabolic rates from standing rest to 3000 BTU/hr (880 W). The bulk of the PLSS 2.0 was at ambient pressure but effluent water vapor from the Spacesuit Water Membrane Evaporator (SWME) and the Auxiliary Membrane Evaporator (Mini-ME), and effluent carbon dioxide from the Rapid Cycle Amine (RCA) were ported to vacuum to test performance of these components in flight-like conditions. One of the objectives of this test was to determine the heat transfer coefficient (UA) of the Liquid Cooling Garment (LCG). The UA, an important factor for modeling the heat rejection of an LCG, was determined in a variety of conditions by varying inlet water temperature, flowrate, and metabolic rate. Three LCG configurations were tested: the Extravehicular Mobility Unit (EMU) LCG, the Oceaneering Space Systems (OSS) LCG, and the OSS auxiliary LCG. Other factors influencing accurate UA determination, such as overall heat balance, LCG fit, and the skin temperature measurement, will also be discussed.

  14. Experimental determination of cavitation thresholds in liquid water and mercury

    International Nuclear Information System (INIS)

    Taleyarkhan, R.P.; West, C.D.; Moraga, F.

    1998-01-01

    An overview is provided on cavitation threshold measurement experiments for water and mercury. Various aspects to be considered that affect onset determination are discussed along with design specifications developed for construction of appropriate apparatus types. Both static and transient-cavitation effects were studied using radically different apparatus designs. Preliminary data are presented for cavitation thresholds for water and mercury over a range of temperatures in static and high-frequency environments. Implications and issues related to spallation neutron source target designs and operation are discussed

  15. Determination of dynamic fracture toughness using a new experimental technique

    Science.gov (United States)

    Cady, Carl M.; Liu, Cheng; Lovato, Manuel L.

    2015-09-01

    In other studies dynamic fracture toughness has been measured using Charpy impact and modified Hopkinson Bar techniques. In this paper results will be shown for the measurement of fracture toughness using a new test geometry. The crack propagation velocities range from ˜0.15 mm/s to 2.5 m/s. Digital image correlation (DIC) will be the technique used to measure both the strain and the crack growth rates. The boundary of the crack is determined using the correlation coefficient generated during image analysis and with interframe timing the crack growth rate and crack opening can be determined. A comparison of static and dynamic loading experiments will be made for brittle polymeric materials. The analysis technique presented by Sammis et al. [1] is a semi-empirical solution, however, additional Linear Elastic Fracture Mechanics analysis of the strain fields generated as part of the DIC analysis allow for the more commonly used method resembling the crack tip opening displacement (CTOD) experiment. It should be noted that this technique was developed because limited amounts of material were available and crack growth rates were to fast for a standard CTOD method.

  16. Determination of dynamic fracture toughness using a new experimental technique

    Directory of Open Access Journals (Sweden)

    Cady Carl M.

    2015-01-01

    Full Text Available In other studies dynamic fracture toughness has been measured using Charpy impact and modified Hopkinson Bar techniques. In this paper results will be shown for the measurement of fracture toughness using a new test geometry. The crack propagation velocities range from ∼0.15 mm/s to 2.5 m/s. Digital image correlation (DIC will be the technique used to measure both the strain and the crack growth rates. The boundary of the crack is determined using the correlation coefficient generated during image analysis and with interframe timing the crack growth rate and crack opening can be determined. A comparison of static and dynamic loading experiments will be made for brittle polymeric materials. The analysis technique presented by Sammis et al. [1] is a semi-empirical solution, however, additional Linear Elastic Fracture Mechanics analysis of the strain fields generated as part of the DIC analysis allow for the more commonly used method resembling the crack tip opening displacement (CTOD experiment. It should be noted that this technique was developed because limited amounts of material were available and crack growth rates were to fast for a standard CTOD method.

  17. EXPERIMENTAL AND CLINICAL SIGNIFICANCE OF RENAL FUNCTIONAL RESERVE DETERMINATION

    Directory of Open Access Journals (Sweden)

    Jernej Pajek

    2002-07-01

    Full Text Available Background. Renal functional reserve (RFR is defined as the temporary increase in glomerular filtration rate (GFR which follows the ingestion of proteins or infusion of aminoacids. This renal vasodilatatory response is probably mediated by several mechanisms, with nitric oxide being one of the most important mediators. In the last years significant progress in measuring renal functional reserve has been achieved on the basis of improvements in methods for accurate and timely appropriate GFR measurement. The method of GFR measurement using the sinistrin clearence calculation after bolus injection of sinistrin is increasingly employed.Conclusions. The article presents the latest results of experiments with RFR using this method and compares them with older reports. RFR is affected by several patophysiological processes: arterial hypertension, diabetes mellitus, deteriorating function of transplanted kidney. The results and impact of RFR determination in this conditions are described. Finally, potential for further research of RFR in atherosclerotic vascular disease is considered. Accurate determination of RFR is important for detection of early renal hemodynamic abnormalities, which can be influenced by therapeutic interventions and in this way the progression of renal functional deterioration could be prevented or at least slowed.

  18. Experimental Determination Of Soft Wheat Flour Thermal Parameters

    Directory of Open Access Journals (Sweden)

    Božiková Monika

    2015-03-01

    Full Text Available This article focuses on temperature relations of selected thermophysical parameters for soft wheat flour. The main aim of experiment was to determine the thermal conductivity, thermal diffusivity and volume specific heat of soft wheat flour in Slovakia marked as Špeciál 00 Extra. Measurements were performed in laboratory settings. Thermal parameters were measured using the thermal analyser Isomet 2104 with two types of probes - a linear probe and plane probe. Measurement by the linear probe is based on a hot wire method, and measurement by the plane probe is based on a simplified plane source method. Both methods are described in the text. Two types of measurement method were used because of the non-homogenous structure of measured material. All thermophysical parameters were measured during the temperature stabilisation in the temperature interval 5-24 °C. Obtained graphical relations had linear increasing progresses with high values of determination coefficients in all cases. Measurement results showed that measurement method has no significant influence on thermophysical parameters values.

  19. Volumetric display using a roof mirror grid array

    Science.gov (United States)

    Miyazaki, Daisuke; Hirano, Noboru; Maeda, Yuuki; Ohno, Keisuke; Maekawa, Satoshi

    2010-02-01

    A volumetric display system using a roof mirror grid array (RMGA) is proposed. The RMGA consists of a two-dimensional array of dihedral corner reflectors and forms a real image at a plane-symmetric position. A two-dimensional image formed with a RMGA is moved at thigh speed by a mirror scanner. Cross-sectional images of a three-dimensional object are displayed in accordance with the position of the image plane. A volumetric image can be observed as a stack of the cross-sectional images by high-speed scanning. Image formation by a RMGA is free from aberrations. Moreover, a compact optical system can be constructed because a RMGA doesn't have a focal length. An experimental volumetric display system using a galvanometer mirror and a digital micromirror device was constructed. The formation of a three-dimensional image consisting of 1024 × 768 × 400 voxels is confirmed by the experimental system.

  20. Experimental determination of the segregation process using computer tomography

    Directory of Open Access Journals (Sweden)

    Konstantin Beckmann

    2016-07-01

    Full Text Available Modelling methods such as DEM and CFD are increasingly used for developing high efficient combine cleaning systems. For this purpose it is necessary to verify the complex segregation and separation processes in the combine cleaning system. One way is to determine the segregation and separation function using 3D computer tomography (CT. This method makes it possible to visualize and analyse the movement behaviour of the components of the mixture during the segregation and separation process as well as the derivation of descriptive process parameters. A mechanically excited miniature test rig was designed and built at the company CLAAS Selbstfahrende Erntemaschinen GmbH to achieve this aim. The investigations were carried out at the Fraunhofer Institute for Integrated Circuits IIS. Through the evaluation of the recorded images the segregation process is described visually. A more detailed analysis enabled the development of segregation and separation function based on the different densities of grain and material other than grain.

  1. On the Experimental Determination of the One-Way Speed of Light

    Science.gov (United States)

    Perez, Israel

    2011-01-01

    In this paper the question of the isotropy of the one-way speed of light is addressed from an experimental perspective. In particular, we analyse two experimental methods commonly used in its determination. The analysis is aimed at clarifying the view that the one-way speed of light cannot be determined by techniques in which physical entities…

  2. Experimental study determining the mechanical properties of dental floss holders.

    Science.gov (United States)

    Wolff, Anna; Pritsch, Maria; Dörfer, Christof; Staehle, Hans Jörg

    2011-06-01

    This study determined the mechanical properties of 19 dental floss holders. Eight single-use holders and 11 reusable ones were tested. An in vitro model with dental proximal contact strength of 8 N was created. Every device had to pass the proximal contact 30 times. We measured (1) the displacement of the floss [mm], (2) the force [N] necessary to pass the proximal contact after the 30th passage, (3) the loosening of the floss (offset [mm]), and (4) the change in the distance between the branches [mm]. Each measurement was repeated seven times. The results are displacement of the floss after 30 passages, 2.0 to 9.2 mm; passage force, 2.6 to 11 N; increases in branch distance, 0-2.9 mm; offset of the floss, 0-1.8 mm (all numbers are medians). Based on cleaning a full dentition (30 passages), we suggest introducing minimal requirements of floss, ≥11 N for the force, and dental floss holders vary extremely in their mechanical properties. Their effective use seems often impossible due to limited mechanical properties.

  3. Theoretical and experimental analyses of optimal experimental design for determination of hydraulic conductivity of cell membrane.

    Science.gov (United States)

    Zhou, Xiaoming; Gao, Frank; Shu, Zhiquan; Chung, Jae-Hyun; Heimfeld, Shelly; Gao, Dayong

    2010-09-01

    Determination of cell hydraulic conductivity (Lp) is required to predict the optimal conditions for cell cryopreservation. One of the critical procedures associated with the determination of Lp is to measure the kinetics of cell volume change in response to a sudden cell exposure to anisosmotic media until the cells achieve an osmotic equilibrium state. To achieve accurate measurement, it should be ensured that (1) the cell osmotic equilibration process is sufficiently slow, and (2) the total cell volume change (ΔV) is much larger than the resolution of the measuring device (δ). In this article, a cell's half volume excursion time (t*) was defined as the time in which osmotically active cell water volume increases or decreases by half of its maximum change. Based on the water transport equations, a series of analytical solutions were derived. The t* and ΔV were expressed as functions of 2 control variables: initial intracellular osmolality (Mo) and extracellular osmolality (Me), and the effects of Me and Mo on t* and ΔV were predicted theoretically. The predictions were confirmed by performing experiments using two different cell types. In the light of this study, a strategy to optimize the experiment design for the Lp determination is suggested.

  4. Methodology for the Experimental Determination of the Powertrain’s Inertia Ellipsoid and its Verification

    Directory of Open Access Journals (Sweden)

    Brabec Pavel

    2017-01-01

    Full Text Available This paper summarizes current scientific knowledge and the results of a study focused on the determination of a powertrain’s inertia ellipsoid. The work deals with the application of methods for the experimental determination of the inertia matrix and summarizes their basic potential. The work describes a proposed computational algorithm by means of which the inertia ellipsoid can be determined. The experimental section of the work presents the results of measurements for internal combustion engines (powertrains.

  5. Efficient threshold for volumetric segmentation

    Science.gov (United States)

    Burdescu, Dumitru D.; Brezovan, Marius; Stanescu, Liana; Stoica Spahiu, Cosmin; Ebanca, Daniel

    2015-07-01

    Image segmentation plays a crucial role in effective understanding of digital images. However, the research on the existence of general purpose segmentation algorithm that suits for variety of applications is still very much active. Among the many approaches in performing image segmentation, graph based approach is gaining popularity primarily due to its ability in reflecting global image properties. Volumetric image segmentation can simply result an image partition composed by relevant regions, but the most fundamental challenge in segmentation algorithm is to precisely define the volumetric extent of some object, which may be represented by the union of multiple regions. The aim in this paper is to present a new method to detect visual objects from color volumetric images and efficient threshold. We present a unified framework for volumetric image segmentation and contour extraction that uses a virtual tree-hexagonal structure defined on the set of the image voxels. The advantage of using a virtual tree-hexagonal network superposed over the initial image voxels is that it reduces the execution time and the memory space used, without losing the initial resolution of the image.

  6. Volumetric polymerization shrinkage of contemporary composite resins

    Directory of Open Access Journals (Sweden)

    Halim Nagem Filho

    2007-10-01

    Full Text Available The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymerization shrinkage of 7 contemporary composite resins (Definite, Suprafill, SureFil, Filtek Z250, Fill Magic, Alert, and Solitaire to determine whether there are differences among these materials. The tests were conducted with precision of 0.1 mg. The volumetric shrinkage was measured by hydrostatic weighing before and after polymerization and calculated by known mathematical equations. One-way ANOVA (a or = 0.05 was used to determine statistically significant differences in volumetric shrinkage among the tested composite resins. Suprafill (1.87±0.01 and Definite (1.89±0.01 shrank significantly less than the other composite resins. SureFil (2.01±0.06, Filtek Z250 (1.99±0.03, and Fill Magic (2.02±0.02 presented intermediate levels of polymerization shrinkage. Alert and Solitaire presented the highest degree of polymerization shrinkage. Knowing the polymerization shrinkage rates of the commercially available composite resins, the dentist would be able to choose between using composite resins with lower polymerization shrinkage rates or adopting technical or operational procedures to minimize the adverse effects deriving from resin contraction during light-activation.

  7. Zeolite-filled silicone rubber membranes. Experimental determination of concentration profiles

    NARCIS (Netherlands)

    te Hennepe, H.J.C.; Boswerger, W.B.F.; Bargeman, D.; Bargeman, D.; Mulder, M.H.V.; Smolders, C.A.; Smolders, C.A.

    1994-01-01

    Permeant concentrations in silicalite-filled silicone rubber membranes during pervaporation of propanol/water mixtures were measured using multi-layered membranes. Experimentally determined concentration profiles show that the propanol concentration in the silicalite-filled membrane increases with

  8. Sizing the height of discontinuities, their characterisation in planar/ volumetric by phased array technique based on diffracted echoes

    International Nuclear Information System (INIS)

    Nardoni, G.; Certo, M.; Nardoni, P.; Feroldi, M.; Nardoni, D.; Possenti, L.; Filosi, A.; Quetti, S.

    2009-01-01

    This report demonstrate and discuss the result of experimental works carried out with the scope to study a procedure for improving the characterization (planar volumetric) and sizing the height of discontinuities detected by ultrasonic computerized systems like TOFD, PHASED ARRAY, C-B SCAN. To comply with code case 2235.9 the acceptance criteria illustrated in Tab 1,2,3 shall be applied. For TOFD the procedure for the calculation of the height is well determined and it is the most accurate with respect to any other ultrasonic technique. For PHASED ARRAY the procedures are on developing path. The aim of the present experimental test is to found criteria for the calculation of the height where Phased Array Technique is used. In addition the research has the scope to identify procedure for the characterization of discontinuities in planar and volumetric. The results of the experimental tests has been demonstrated two important achievements:1) The distance between the diffracted echoes is proportional to the height of the discontinuity;2) The ratio between the amplitude of the diffracted echoes could be considered a good criteria for the characterization of discontinuities in planar or volumetric. (author)

  9. Determination, by using GPR, of the volumetric water content in structures, sub-structures, foundations and soil - ongoing activities in Working Project 2.5 of COST Action TU1208

    Science.gov (United States)

    Tosti, Fabio; Slob, Evert

    2015-04-01

    This work will endeavour to review the current status of research activities carried out in Working Project 2.5 'Determination, by using GPR, of the volumetric water content in structures, sub-structures, foundations and soil' within the framework of Working Group 2 'GPR surveying of pavements, bridges, tunnels and buildings; underground utility and void sensing' of the COST (European COoperation in Science and Technology) Action TU1208 'Civil Engineering Applications of Ground Penetrating Radar' (www.GPRadar.eu). Overall, the Project includes 55 Participants from over 21 countries representing 33 Institutions. By considering the type of Institution, a percentage of 64% (35 units) comes from the academic world, while Research Centres and Companies include, respectively, the 27% (15 units) and 9% (5 units) of Institutions. Geographically speaking, Europe is the continent most represented with 18 out of 21 countries, followed by Africa (2 countries) and Asia (1 country). In more details and according to the Europe sub-regions classification provided by the United Nations, Southern Europe includes 39% of countries, Western Europe 27%, while Northern and Eastern Europe are equally present with 17% of countries each. Relying on the main purpose of Working Project 2.5, namely, the ground-penetrating radar-based evaluation of volumetric water content in structures, substructures , foundations, and soils, four main issues have been overall addressed over the first two years of activities. The first one, has been related to provide a comprehensive state of the art on the topic, due to the wide-ranging applications covered in the main disciplines of civil engineering, differently demanding. In this regard, two main publications reviewing the state of the art have been produced [1,2]. Secondly, discussions among Working Group Chairs and other Working Project Leaders have been undertaken and encouraged to avoid the risk of overlapping amongst similar topics from other Working

  10. Design, Implementation and Characterization of a Quantum-Dot-Based Volumetric Display

    Science.gov (United States)

    Hirayama, Ryuji; Naruse, Makoto; Nakayama, Hirotaka; Tate, Naoya; Shiraki, Atsushi; Kakue, Takashi; Shimobaba, Tomoyoshi; Ohtsu, Motoichi; Ito, Tomoyoshi

    2015-02-01

    In this study, we propose and experimentally demonstrate a volumetric display system based on quantum dots (QDs) embedded in a polymer substrate. Unlike conventional volumetric displays, our system does not require electrical wiring; thus, the heretofore unavoidable issue of occlusion is resolved because irradiation by external light supplies the energy to the light-emitting voxels formed by the QDs. By exploiting the intrinsic attributes of the QDs, the system offers ultrahigh definition and a wide range of colours for volumetric displays. In this paper, we discuss the design, implementation and characterization of the proposed volumetric display's first prototype. We developed an 8 × 8 × 8 display comprising two types of QDs. This display provides multicolour three-type two-dimensional patterns when viewed from different angles. The QD-based volumetric display provides a new way to represent images and could be applied in leisure and advertising industries, among others.

  11. Definition and experimental determination of a soil-water retention surface

    OpenAIRE

    Salager, S.; El Youssoufi, M. S.; Saix, C.

    2010-01-01

    International audience; This paper deals with the definition and determination methods of the soil-water retention surface (SWRS), which is the tool used to present the hydromechanical behaviour of soils to highlight both the effect of suction on the change in water and total volumes and the effect of deformation with respect to the water retention capability. An experimental method is introduced to determine the SWRS and applied to a clayey silty sand. The determination of this surface is ba...

  12. VOLUMETRIC LEAK DETECTION IN LARGE UNDERGROUND STORAGE TANKS - VOLUME I

    Science.gov (United States)

    A set of experiments was conducted to determine whether volumetric leak detection system presently used to test underground storage tanks (USTs) up to 38,000 L (10,000 gal) in capacity could meet EPA's regulatory standards for tank tightness and automatic tank gauging systems whe...

  13. An experimental method to determine the electrostatic field enhancement factor of a practical conductor surface

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson; Crichton, George C

    1989-01-01

    A method of determining the field enhancement factor of a practical conductor is presented. The method is developed from a modified theory of discharge onset in a gaseous medium. This modification incorporates the influence of conductor surface roughness. Onset data from an experimental study...... that utilized electrodes of varying surface roughness are examined, and the results obtained using the proposed method are discussed with reference to both the underlying theory and the practical aspects of the experimental measurements...

  14. MIDAS. An algorithm for the extraction of modal information from experimentally determined transfer functions

    International Nuclear Information System (INIS)

    Durrans, R.F.

    1978-12-01

    In order to design reactor structures to withstand the large flow and acoustic forces present it is necessary to know something of their dynamic properties. In many cases these properties cannot be predicted theoretically and it is necessary to determine them experimentally. The algorithm MIDAS (Modal Identification for the Dynamic Analysis of Structures) which has been developed at B.N.L. for extracting these structural properties from experimental data is described. (author)

  15. Experimental-calculation technique for Ksub(IC) determination using the samples of decreased dimensions

    International Nuclear Information System (INIS)

    Vinokurov, V.A.; Dymshits, A.V.; Pirusskij, M.V.; Ovsyannikov, B.M.; Kononov, V.V.

    1981-01-01

    A possibility to decrease the size of samples, which is necessary for the reliable determination of fractUre toughness Ksub(1c), is established. The dependences of crack-resistance caracteristics on the sample dimensions are determined experimentally. The static bending tests are made using the 1251 model of ''Instron'' installation with a specially designed device. The samples of the 20KhNMF steel have been tested. It is shown that the Ksub(1c) value, determined for the samples with the largest netto cross section (50x100 rm), is considerably lower than Ksub(1c) values, determined for the samples with the decreased sizes. it is shown that the developed experimental-calculated method of Ksub(1c) determination can be practically used for the samples of the decreased sizes with the introduction of the corresponding amendment coefficient [ru

  16. A comparison of experimentally-determined plasma oscillation frequencies with simulation.

    Science.gov (United States)

    Peterson, Bryan G.; Hart, Grant W.; Spencer, Ross L.

    2002-11-01

    The frequencies of the various plasma oscillation modes (diocotron and Trivelpiece-Gould modes) in a non-neutral electron plasma are dependent on both the plasma temperature and on the plasma density profile. There have been difficulties in calculating mode frequencies that match those determined experimentally. We have experimentally measured the frequencies of the diocotron and T-G modes as well as the plasma density profile and temperature for several plasma conditions. These frequencies are compared with those obtained from kinetic simulations to determine the conditions necessary for a consistent fit to all the measured frequencies.

  17. Gradients estimation from random points with volumetric tensor in turbulence

    Science.gov (United States)

    Watanabe, Tomoaki; Nagata, Koji

    2017-12-01

    We present an estimation method of fully-resolved/coarse-grained gradients from randomly distributed points in turbulence. The method is based on a linear approximation of spatial gradients expressed with the volumetric tensor, which is a 3 × 3 matrix determined by a geometric distribution of the points. The coarse grained gradient can be considered as a low pass filtered gradient, whose cutoff is estimated with the eigenvalues of the volumetric tensor. The present method, the volumetric tensor approximation, is tested for velocity and passive scalar gradients in incompressible planar jet and mixing layer. Comparison with a finite difference approximation on a Cartesian grid shows that the volumetric tensor approximation computes the coarse grained gradients fairly well at a moderate computational cost under various conditions of spatial distributions of points. We also show that imposing the solenoidal condition improves the accuracy of the present method for solenoidal vectors, such as a velocity vector in incompressible flows, especially when the number of the points is not large. The volumetric tensor approximation with 4 points poorly estimates the gradient because of anisotropic distribution of the points. Increasing the number of points from 4 significantly improves the accuracy. Although the coarse grained gradient changes with the cutoff length, the volumetric tensor approximation yields the coarse grained gradient whose magnitude is close to the one obtained by the finite difference. We also show that the velocity gradient estimated with the present method well captures the turbulence characteristics such as local flow topology, amplification of enstrophy and strain, and energy transfer across scales.

  18. Automated MRI Volumetric Analysis in Patients with Rasmussen Syndrome.

    Science.gov (United States)

    Wang, Z I; Krishnan, B; Shattuck, D W; Leahy, R M; Moosa, A N V; Wyllie, E; Burgess, R C; Al-Sharif, N B; Joshi, A A; Alexopoulos, A V; Mosher, J C; Udayasankar, U; Jones, S E

    2016-12-01

    Rasmussen syndrome, also known as Rasmussen encephalitis, is typically associated with volume loss of the affected hemisphere of the brain. Our aim was to apply automated quantitative volumetric MR imaging analyses to patients diagnosed with Rasmussen encephalitis, to determine the predictive value of lobar volumetric measures and to assess regional atrophy differences as well as monitor disease progression by using these measures. Nineteen patients (42 scans) with diagnosed Rasmussen encephalitis were studied. We used 2 control groups: one with 42 age- and sex-matched healthy subjects and the other with 42 epileptic patients without Rasmussen encephalitis with the same disease duration as patients with Rasmussen encephalitis. Volumetric analysis was performed on T1-weighted images by using BrainSuite. Ratios of volumes from the affected hemisphere divided by those from the unaffected hemisphere were used as input to a logistic regression classifier, which was trained to discriminate patients from controls. Using the classifier, we compared the predictive accuracy of all the volumetric measures. These ratios were used to further assess regional atrophy differences and correlate with epilepsy duration. Interhemispheric and frontal lobe ratios had the best prediction accuracy for separating patients with Rasmussen encephalitis from healthy controls and patient controls without Rasmussen encephalitis. The insula showed significantly more atrophy compared with all the other cortical regions. Patients with longitudinal scans showed progressive volume loss in the affected hemisphere. Atrophy of the frontal lobe and insula correlated significantly with epilepsy duration. Automated quantitative volumetric analysis provides accurate separation of patients with Rasmussen encephalitis from healthy controls and epileptic patients without Rasmussen encephalitis, and thus may assist the diagnosis of Rasmussen encephalitis. Volumetric analysis could also be included as part of

  19. Volumetric velocity measurements on flows through heart valves

    Science.gov (United States)

    Troolin, Daniel; Amatya, Devesh; Longmire, Ellen

    2009-11-01

    Volumetric velocity fields inside two types of artificial heart valves were obtained experimentally through the use of volumetric 3-component velocimetry (V3V). Index matching was used to mitigate the effects of optical distortions due to interfaces between the fluid and curved walls. The steady flow downstream of a mechanical valve was measured and the results matched well with previously obtained 2D PIV results, such as those of Shipkowitz et al. (2002). Measurements upstream and downstream of a deformable silicone valve in a pulsatile flow were obtained and reveal significant three-dimensional features of the flow. Plots and movies will be shown, and a detailed discussion of the flow and various experimental considerations will be included. Reference: Shipkowitz, T, Ambrus J, Kurk J, Wickramasinghe K (2002) Evaluation technique for bileaflet mechanical valves. J. Heart Valve Disease. 11(2) pp. 275-282.

  20. Experimental preliminary exploration on determining grease thickness simulated by paraffin in petroleum pipelines

    International Nuclear Information System (INIS)

    Zhao Nongxiao; Arkin, Abulim; Yang Kunjie; Wang Shiheng; Shi Feiyue

    2009-01-01

    1.25 MeV γ-ray of 60 Co Compton scattering coefficient in the simple of paraffin,are measured by γ-ray energy spectrum analysis in two determining means. At the same experimental condition, we have used this scattering coefficient to determining grease thickness simulated by paraffin. The result show the average relative difference is about 1.29% for the best group. (authors)

  1. Determination of the angle of attack on the mexico rotor using experimental data

    DEFF Research Database (Denmark)

    Yang, Hua; Shen, Wen Zhong; Sørensen, Jens Nørkær

    2010-01-01

    characteristics from experimental data on the MEXICO (Model Experiments in controlled Conditions) rotor. Detailed surface pressure and Particle Image Velocimetry (PIV) flow field at different rotor azimuth positions were examined for determining the sectional airfoil data. It is worthwhile noting that the present...

  2. Fast, Computer Supported Experimental Determination of Absolute Zero Temperature at School

    Science.gov (United States)

    Bogacz, Bogdan F.; Pedziwiatr, Antoni T.

    2014-01-01

    A simple and fast experimental method of determining absolute zero temperature is presented. Air gas thermometer coupled with pressure sensor and data acquisition system COACH is applied in a wide range of temperature. By constructing a pressure vs temperature plot for air under constant volume it is possible to obtain--by extrapolation to zero…

  3. Theoretical and Experimental Determination of the Crack Width in Reinforced Concrete at Very Low Temperatures

    NARCIS (Netherlands)

    V.d. Veen, G.

    1990-01-01

    The compressive strength, the tensile splitting strength, the stress strain relationship and the thermal deformation of concrete are determined experimentally as a function of temperature. Theoretical formulae are derived based on the classical bond stress-slip theory to predict crack width and

  4. Inkjet printing-based volumetric display projecting multiple full-colour 2D patterns

    Science.gov (United States)

    Hirayama, Ryuji; Suzuki, Tomotaka; Shimobaba, Tomoyoshi; Shiraki, Atsushi; Naruse, Makoto; Nakayama, Hirotaka; Kakue, Takashi; Ito, Tomoyoshi

    2017-04-01

    In this study, a method to construct a full-colour volumetric display is presented using a commercially available inkjet printer. Photoreactive luminescence materials are minutely and automatically printed as the volume elements, and volumetric displays are constructed with high resolution using easy-to-fabricate means that exploit inkjet printing technologies. The results experimentally demonstrate the first prototype of an inkjet printing-based volumetric display composed of multiple layers of transparent films that yield a full-colour three-dimensional (3D) image. Moreover, we propose a design algorithm with 3D structures that provide multiple different 2D full-colour patterns when viewed from different directions and experimentally demonstrate prototypes. It is considered that these types of 3D volumetric structures and their fabrication methods based on widely deployed existing printing technologies can be utilised as novel information display devices and systems, including digital signage, media art, entertainment and security.

  5. A volumetric flow sensor for automotive injection systems

    Science.gov (United States)

    Schmid, U.; Krötz, G.; Schmitt-Landsiedel, D.

    2008-04-01

    For further optimization of the automotive power train of diesel engines, advanced combustion processes require a highly flexible injection system, provided e.g. by the common rail (CR) injection technique. In the past, the feasibility to implement injection nozzle volumetric flow sensors based on the thermo-resistive measurement principle has been demonstrated up to injection pressures of 135 MPa (1350 bar). To evaluate the transient behaviour of the system-integrated flow sensors as well as an injection amount indicator used as a reference method, hydraulic simulations on the system level are performed for a CR injection system. Experimentally determined injection timings were found to be in good agreement with calculated values, especially for the novel sensing element which is directly implemented into the hydraulic system. For the first time pressure oscillations occurring after termination of the injection pulse, predicted theoretically, could be verified directly in the nozzle. In addition, the injected amount of fuel is monitored with the highest resolution ever reported in the literature.

  6. Radiologist assessment of breast density by BI-RADS categories versus fully automated volumetric assessment.

    Science.gov (United States)

    Gweon, Hye Mi; Youk, Ji Hyun; Kim, Jeong-Ah; Son, Eun Ju

    2013-09-01

    The objective of our study was to estimate mammographic breast density using a fully automated volumetric breast density measurement method in comparison with BI-RADS breast density categories determined by radiologists. A total of 791 full-field digital mammography examinations with standard views were evaluated by three blinded radiologists as BI-RADS density categories 1-4. For fully automated volumetric analysis, volumetric breast density was calculated with fully automated software. The volume of fibroglandular tissue, the volume of the breast, and the volumetric percentage density were provided. The weighted overall kappa was 0.48 (moderate agreement) for the three radiologists' estimates of BI-RADS density. Pairwise comparisons of the radiologists' measurements of BI-RADS density revealed moderate to substantial agreement, with kappa values ranging from 0.51 to 0.64. There was a significant difference in mean volumetric breast density among the BI-RADS density categories, and the mean volumetric breast density increased as the BI-RADS density category increased (pBI-RADS categories and fully automated volumetric breast density (ρ=0.765, pBI-RADS density categories. Mammographic density assessment with the fully automated volumetric method may be used to assign BI-RADS density categories.

  7. The Influence of Water and Mineral Oil On Volumetric Losses in a Hydraulic Motor

    OpenAIRE

    Śliwiński Pawel

    2017-01-01

    In this paper volumetric losses in hydraulic motor supplied with water and mineral oil (two liquids having significantly different viscosity and lubricating properties) are described and compared. The experimental tests were conducted using an innovative hydraulic satellite motor, that is dedicated to work with different liquids, including water. The sources of leaks in this motor are also characterized and described. On this basis, a mathematical model of volumetric losses and model of effec...

  8. ANALYTICAL AND EXPERIMENTAL DETERMINATION OF STRESSES IN THE PLANE COMPOSITE PLATES

    Directory of Open Access Journals (Sweden)

    Corneliu MOROIANU

    2010-06-01

    Full Text Available This work presents the mathematical method for solving the differential equations by means of which we can determine the stresses in the plane composite plates used to build crafts. . The results analytically determined are compared with the experimental ones. The first chapter of the work presents the differential equation system for composite materials (glass reinforced polyester resin to determine the stress function F(x,y and the deflection w(x,y by which the stress condition in the composite is established. In chapter 2 they are presented the analytical resolution methods (simple and double trigonometric series, approximate analytical methods (Ritz and finite element method (COSMOS and ALGOR programs. In chapter 3 the theoretical results are compared with the experimental ones obtained on a plate model made by five woven roving plies produced in FIROS S.A. Bucharest. The impregnation resin is NESTRAPOL 450 produced by POLICOLOR S.A. Bucharest.

  9. Experimental determination of the absolute infrared absorption intensities of formyl radical HCO.

    Science.gov (United States)

    Ryazantsev, Sergey V; Tyurin, Daniil A; Feldman, Vladimir I

    2017-12-05

    Formyl radical HCO is an important reactive intermediate in combustion, atmospheric and extraterrestrial chemistry. Like in the case of other transients, the lack of knowledge of the absolute IR intensities limits the quantitative spectroscopic studies on this species. We report the first experimental determination of the absorption intensities for the fundamental vibrational bands of HCO. The measurements have been performed using matrix-isolation FTIR spectroscopy. Determination of the values was based on the repeated photodissociation and thermal recovery of the HCO radical using the known value of the absorption coefficient of CO. The experimentally determined values (93.2±6.0, 67.2±4.5, and 109.2±6.6kmmol -1 for the ν 1 , ν 2 , and ν 3 modes, respectively) have been compared to the calculated IR intensities obtained by DFT and UCCSD(T) computations. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Visualization and computer graphics on isotropically emissive volumetric displays.

    Science.gov (United States)

    Mora, Benjamin; Maciejewski, Ross; Chen, Min; Ebert, David S

    2009-01-01

    The availability of commodity volumetric displays provides ordinary users with a new means of visualizing 3D data. Many of these displays are in the class of isotropically emissive light devices, which are designed to directly illuminate voxels in a 3D frame buffer, producing X-ray-like visualizations. While this technology can offer intuitive insight into a 3D object, the visualizations are perceptually different from what a computer graphics or visualization system would render on a 2D screen. This paper formalizes rendering on isotropically emissive displays and introduces a novel technique that emulates traditional rendering effects on isotropically emissive volumetric displays, delivering results that are much closer to what is traditionally rendered on regular 2D screens. Such a technique can significantly broaden the capability and usage of isotropically emissive volumetric displays. Our method takes a 3D dataset or object as the input, creates an intermediate light field, and outputs a special 3D volume dataset called a lumi-volume. This lumi-volume encodes approximated rendering effects in a form suitable for display with accumulative integrals along unobtrusive rays. When a lumi-volume is fed directly into an isotropically emissive volumetric display, it creates a 3D visualization with surface shading effects that are familiar to the users. The key to this technique is an algorithm for creating a 3D lumi-volume from a 4D light field. In this paper, we discuss a number of technical issues, including transparency effects due to the dimension reduction and sampling rates for light fields and lumi-volumes. We show the effectiveness and usability of this technique with a selection of experimental results captured from an isotropically emissive volumetric display, and we demonstrate its potential capability and scalability with computer-simulated high-resolution results.

  11. A new method to determine the number of experimental data using statistical modeling methods

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jung-Ho; Kang, Young-Jin; Lim, O-Kaung; Noh, Yoojeong [Pusan National University, Busan (Korea, Republic of)

    2017-06-15

    For analyzing the statistical performance of physical systems, statistical characteristics of physical parameters such as material properties need to be estimated by collecting experimental data. For accurate statistical modeling, many such experiments may be required, but data are usually quite limited owing to the cost and time constraints of experiments. In this study, a new method for determining a rea- sonable number of experimental data is proposed using an area metric, after obtaining statistical models using the information on the underlying distribution, the Sequential statistical modeling (SSM) approach, and the Kernel density estimation (KDE) approach. The area metric is used as a convergence criterion to determine the necessary and sufficient number of experimental data to be acquired. The pro- posed method is validated in simulations, using different statistical modeling methods, different true models, and different convergence criteria. An example data set with 29 data describing the fatigue strength coefficient of SAE 950X is used for demonstrating the performance of the obtained statistical models that use a pre-determined number of experimental data in predicting the probability of failure for a target fatigue life.

  12. Iterative reconstruction of volumetric particle distribution

    International Nuclear Information System (INIS)

    Wieneke, Bernhard

    2013-01-01

    For tracking the motion of illuminated particles in space and time several volumetric flow measurement techniques are available like 3D-particle tracking velocimetry (3D-PTV) recording images from typically three to four viewing directions. For higher seeding densities and the same experimental setup, tomographic PIV (Tomo-PIV) reconstructs voxel intensities using an iterative tomographic reconstruction algorithm (e.g. multiplicative algebraic reconstruction technique, MART) followed by cross-correlation of sub-volumes computing instantaneous 3D flow fields on a regular grid. A novel hybrid algorithm is proposed here that similar to MART iteratively reconstructs 3D-particle locations by comparing the recorded images with the projections calculated from the particle distribution in the volume. But like 3D-PTV, particles are represented by 3D-positions instead of voxel-based intensity blobs as in MART. Detailed knowledge of the optical transfer function and the particle image shape is mandatory, which may differ for different positions in the volume and for each camera. Using synthetic data it is shown that this method is capable of reconstructing densely seeded flows up to about 0.05 ppp with similar accuracy as Tomo-PIV. Finally the method is validated with experimental data. (paper)

  13. An experimental determination of the isochoric heat capacity, P-V-T data and thermodynamic derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Gritsenko, A.I.; Buleyko, V.M.; Nagayev, V.B.

    1984-01-01

    An experimental calorimetric device is developed and manufactured and used to investigate the thermophysical properties of natural gas from the Vuktyl field. The primary thermodynamic parameters of this gas are determined over a wide range of temperatures and pressures. A comparative analysis of the experimental values of these parameters with respect to computed parameters obtained using various equations of state is performed. The derived values for the thermodynamic parameters are recommended for use in thermal engineering computations of surface equipment designs for gas condensate fields which have nearly the same methane and ethane fraction composition as the gas from the Vuktyl field.

  14. Comparative study of sound absorption coefficient determination using FEM method and experimental tests on Kundt's tube

    Science.gov (United States)

    Deaconu, Marius; Toma, Adina Cristina; Dragasanu, Luminita Ioana; Mihai, Dragos

    2017-06-01

    Sound absorption coefficient is a commonly used parameter to characterize the acoustic properties of sound absorbing materials that plays an important role in noise attenuation. For this study a specific material has been chosen in order to be evaluated experimentally and compared with the simulated results. Both simulation and experimental assessments used to estimate the sound absorption coefficient are based on transfer function method in accordance with standard SR EN JSO 10354-2. Results are obtained for 15, 30, 45 mm material sample thickness in order to assess the relationship between absorption coefficient, thickness and frequency response. Comparative analysis is performed to determine differences given by the two approaches.

  15. A reduced volumetric expansion factor plot

    Science.gov (United States)

    Hendricks, R. C.

    1979-01-01

    A reduced volumetric expansion factor plot has been constructed for simple fluids which is suitable for engineering computations in heat transfer. Volumetric expansion factors have been found useful in correlating heat transfer data over a wide range of operating conditions including liquids, gases and the near critical region.

  16. Reference volumetric samples of gamma-spectroscopic sources

    International Nuclear Information System (INIS)

    Taskaev, E.; Taskaeva, M.; Grigorov, T.

    1993-01-01

    The purpose of this investigation is to determine the requirements for matrices of reference volumetric radiation sources necessary for detector calibration. The first stage of this determination consists in analysing some available organic and nonorganic materials. Different sorts of food, grass, plastics, minerals and building materials have been considered, taking into account the various procedures of their processing (grinding, screening, homogenizing) and their properties (hygroscopy, storage life, resistance to oxidation during gamma sterilization). The procedures of source processing, sample preparation, matrix irradiation and homogenization have been determined. A rotation homogenizing device has been elaborated enabling to homogenize the matrix activity irrespective of the vessel geometry. 33 standard volumetric radioactive sources have been prepared: 14 - on organic matrix and 19 - on nonorganic matrix. (author)

  17. Experimental determination of the thermal contact conductance between two solid surfaces by the energy pulse technique

    International Nuclear Information System (INIS)

    Rubin, Gerson Antonio

    1979-01-01

    An experimental procedure for the determination of the thermal contact conductance between two solid surfaces as a function of the contact pressure and the energy of the laser radiation has been developed using the laser pulse method. A rubi laser with variable energy levels was employed as a radiating pulse energy source. The laser beam was allowed to impinge perpendicularly on the front face of a electrolytic iron 73 4 . The temperature fluctuations resulting on the back surface of the sample was detected by a thermocouple, which Is coupled to a PDP-11/45 Computer 32 Kbytes of memory, through a Analog-Digital Converter. A theoretical function, derived exclusively for the problem mentioned in this work, was adjusted by a method of least square fitting of experimental results. This adjustment yielded the value of a parameter related to the contact conductance between two surfaces. The experimental error obtained for the thermal contact conductance was +- 4.9%. (author)

  18. Method of experimental and calculation determination of dissipative properties of carbon

    Science.gov (United States)

    Kazakova, Olga I.; Smolin, Igor Yu.; Bezmozgiy, Iosif M.

    2017-12-01

    This paper describes the process of definition of relations between the damping ratio and strain/state levels in a material. For these purposes, the experimental-calculation approach was applied. The experimental research was performed on plane composite specimens. The tests were accompanied by finite element modeling using the ANSYS software. Optimization was used as a tool for FEM property setting and for finding the above-mentioned relations. A difference between the calculation and experimental results was accepted as objective functions of this optimization. The optimization cycle was implemented using the pSeven DATADVANCE software platform. The developed approach makes it possible to determine the relations between the damping ratio and strain/state levels in the material, which can be used for computer modeling of the structure response under dynamic loading.

  19. On the experimental determination of the one-way speed of light

    International Nuclear Information System (INIS)

    Perez, Israel

    2011-01-01

    In this paper the question of the isotropy of the one-way speed of light is addressed from an experimental perspective. In particular, we analyse two experimental methods commonly used in its determination. The analysis is aimed at clarifying the view that the one-way speed of light cannot be determined by techniques in which physical entities close paths. The procedure employed here will provide epistemological tools so that physicists understand that a direct measurement of the speed not only of light but of any physical entity is by no means trivial. Our results shed light on the physics behind the experiments which may be of interest for both physicists with an elemental knowledge in special relativity and philosophers of science.

  20. Experimental determination of the attachment coefficients of atoms and ions on monodisperse aerosols

    International Nuclear Information System (INIS)

    Porstendoerfer, J.; Roebig, G.; Ahmed, A.

    1979-01-01

    The attachment coefficients of 212 Pb atoms and ions were measured for aerosols in the diameter range 0.1 to 5 μm. The attachment of the Tn-decay products to the aerosol was carried out in laminar flow through a cylindrical tube. Under the same experimental conditions (but without aerosols) the diffusion coefficient of the atoms was determined. The generation of the monodisperse di-2-ethylhexyl sebacate (DEHS) aerosol was carried out by controlled condensation of vapour upon nuclei. The aerosols had standard deviations of 3 to 5%. The aerosol size distributions and concentrations were determined by means of an aerosol size spectrometer, which measured the intensity of the scattered light from single-particles or droplets. The experimental results agree well with the values of the diffusion attachment theory based on the kinetic theory of gases with the assumption of a sticking probability of the Pb atoms, S = 1. (author)

  1. An experimental investigation devoted to determine heat transfer characteristics in a radiant ceiling heating system

    Science.gov (United States)

    Koca, Aliihsan; Acikgoz, Ozgen; Çebi, Alican; Çetin, Gürsel; Dalkilic, Ahmet Selim; Wongwises, Somchai

    2018-02-01

    Investigations on heated ceiling method can be considered as a new research area in comparison to the common wall heating-cooling and cooled ceiling methods. In this work, heat transfer characteristics of a heated radiant ceiling system was investigated experimentally. There were different configurations for a single room design in order to determine the convective and radiative heat transfer rates. Almost all details on the arrangement of the test chamber, hydraulic circuit and radiant panels, the measurement equipment and experimental method including uncertainty analysis were revealed in detail indicating specific international standards. Total heat transfer amount from the panels were calculated as the sum of radiation to the unheated surfaces, convection to the air, and conduction heat loss from the backside of the panels. Integral expression of the view factors was calculated by means of the numerical evaluations using Matlab code. By means of this experimental chamber, the radiative, convective and total heat-transfer coefficient values along with the heat flux values provided from the ceiling to the unheated surrounding surfaces have been calculated. Moreover, the details of 28 different experimental case study measurements from the experimental chamber including the convective, radiative and total heat flux, and heat output results are given in a Table for other researchers to validate their theoretical models and empirical correlations.

  2. Experimental Methodology for Determining Optimum Process Parameters for Production of Hydrous Metal Oxides by Internal Gelation

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J.L.

    2005-10-28

    The objective of this report is to describe a simple but very useful experimental methodology that was used to determine optimum process parameters for preparing several hydrous metal-oxide gel spheres by the internal gelation process. The method is inexpensive and very effective in collection of key gel-forming data that are needed to prepare the hydrous metal-oxide microspheres of the best quality for a number of elements.

  3. An experimental magnetic moment determination method based on spatial harmonic analysis of magnetic flux density signatures

    Directory of Open Access Journals (Sweden)

    A.V. Getman

    2013-12-01

    Full Text Available Theoretical aspects of an experimental determination method for residual and inductive magnetic moments of a technical object are considered. As input data, the technical object magnetic induction signatures obtained under its linear movement near a pair of three-component sensors are used. A magnetic signature integration technique based on spatial harmonic analysis of the magnetic field represented by twenty-four multipole coefficients is introduced.

  4. Optimization of experimental conditions in uranium trace determination using laser time-resolved fluorimetry

    International Nuclear Information System (INIS)

    Baly, L.; Garcia, M.A.

    1996-01-01

    At the present paper a new sample excitation geometry is presented for the uranium trace determination in aqueous solutions by the Time-Resolved Laser-Induced Fluorescence. This new design introduces the laser radiation through the top side of the cell allowing the use of cells with two quartz sides, less expensive than commonly used at this experimental set. Optimization of the excitation conditions, temporal discrimination and spectral selection are presented

  5. Theoretical and experimental determination of mechanical properties of superconducting composite wire

    International Nuclear Information System (INIS)

    Gray, W.H.; Sun, C.T.

    1976-07-01

    The mechanical properties of a composite superconducting (NbTi/Cu) wire are characterized in terms of the mechanical properties of each constituent material. For a particular composite superconducting wire, five elastic material constants were experimentally determined and theoretically calculated. Since the Poisson's ratios for the fiber and the matrix material were very close, there was essentially no (less than 1 percent) difference among all the theoretical predictions for any individual mechanical constant. Because of the expense and difficulty of producing elastic constant data of 0.1 percent accuracy, and therefore conclusively determining which theory is best, no further experiments were performed

  6. Experimental Determination of Third Derivative of the Gibbs Free Energy, G II

    DEFF Research Database (Denmark)

    Koga, Yoshikata; Westh, Peter; Inaba, Akira

    2010-01-01

    We have been evaluating third derivative quantities of the Gibbs free energy, G, by graphically differentiating the second derivatives that are accessible experimentally, and demonstrated their power in elucidating the mixing schemes in aqueous solutions. Here we determine directly one of the third...... derivatives of G, the partial molar entropy-volume cross fluctuation density of 2-butoxyethanol (BE) in the BE–H2O system, SV δ BE . The difference of the heats of compression were directly determined using two identical cells and applying the same pressure change to both cells concurrently. Both cells...

  7. Feasibility of flat-panel volumetric computed tomography (fpVCT) in experimental small animal imaging of osteoporosis - initial experience; Erste Erfahrungen mit einem Flaechendetektor-Volumen-CT (fpVCT) in der experimentellen Osteoporosediagnostik am Kleintiermodell

    Energy Technology Data Exchange (ETDEWEB)

    Valencia, R.; Dullin, C.; Herrmann, K.P.; Kluever, I.; Zaroban, A.; Knollmann, F. [Universitaetsklinikum Goettingen (Germany). Abteilung Diagnostische Radiologie, Goettingen; Stuermer, E.K.; Sehmisch, S. [Universitaetsklinikum Goettingen (Germany). Klinik fuer Unfallchirurgie, Plastische und Wiederherstellungschirurgie; Funke, M. [Klinikum Mittelbaden, Baden-Baden (Germany). Radiologische Klinik an der Stadtklinik

    2006-10-15

    Flat-panel volumetric computed tomography (fpVCT) is a new, noninvasive CT imaging modality with increased isotropic resolution. Technical details, potential applications, and our initial experience with a fpVCT prototype scanner in the imaging of osteoporosis in a rat model are presented. To date, 21 rats have been investigated in vivo with fpVCT. Pharmacologic effects on bone mineral density (BMD) and structure were of special interest. Image evaluation focussed on the second lumbar vertebra and the left femoral bone. To validate measurement results, BMD values calculated with fpVCT were correlated with results of BMD measurements from ashing of the second lumbar vertebra and femoral bones. Our initial results show that fpVCT is capable of detecting differences in BMD between ovariectomized rats treated with estradiol and a control group with high statistical significance (p<0.05), corresponding to ashing as the gold standard. In a rat model, fpVCT imaging is especially useful in longitudinal in vivo investigations of BMD measures. Spatial resolution of up to 150 {mu}m allows imaging of the trabecular structure only in human cadaveric bones. (orig.) [German] Die Flaechendetektor-Volumen-Computertomographie (fpVCT) ist eine neuartige CT-Bildgebungstechnik, die eine gesteigerte isotrope Ortsaufloesung ermoeglicht. In dieser Arbeit wird ueber Technik, Anwendungsmoeglichkeiten und erste Erfahrungen beim Einsatz eines fpVCT-Prototyps in der experimentellen Diagnostik der Osteoporose am Rattenmodell berichtet. Bisher konnten 21 Ratten in vivo am fpVCT untersucht werden. Von besonderem Interesse waren Medikamentenwirkungen auf Knochendichte (''bone mineral density'', BMD) und -struktur. Die Auswertung der gewonnenen Bilddaten fokussierte sich auf den 2. Lendenwirbelkoerper und das linke Femur. Um die Messergebnisse zu ueberpruefen, wurden die mittels fpVCT errechneten BMD-Werte mit den Ergebnissen der Dichtemessung der veraschten 2. LWK und Femora

  8. Thermophysical properties of yacon (Smallanthus sonchifolius: experimental determination and effect of moisture content

    Directory of Open Access Journals (Sweden)

    Camila Augusto Perussello

    2015-01-01

    Full Text Available The knowledge about thermophysical properties of foods is especially important in thermal processing, influencing the design, optimization and cost reduction of the process, as well as the quality and safety of the final product. This article deals with the determination of some thermophysical properties of yacon, namely, specific mass, specific heat, thermal conductivity and thermal diffusivity during the osmo-convective drying. Yacon is a root with approximately 90% w.b. of moisture content, whose high concentration of fructooligosacharydes and antioxidants has gained attention in the food research field. Yacon slices were osmotically dehydrated for 2 hours in a sucralose solution and then dried in a convective tray dryer for 2 hours, varying the osmotic solution’s temperature and stirring rate and temperature of the drying air. All thermophysical properties were determined during the drying process at 30-minute intervals. The thermophysical properties were determined not only experimentally but also calculated by models available in literature based on the product’s centesimal composition. A satisfactory agreement between experimental and predicted results was obtained. Further, empirical models obtained by nonlinear regression were successfully fitted to the experimental data, as a function of moisture content, within a 94% - 3% w.b. range.

  9. Experimental determination of thermal conductivity of soil with a thermal response test

    Directory of Open Access Journals (Sweden)

    Banjac Miloš J.

    2012-01-01

    Full Text Available Optimal design of a borehole heat exchanger, as the outer part of a ground source heat pump heating system, requires information on the thermal properties of the soil. Those data, the effective thermal conductivity of the soil λeff and the average temperature of the soil T0, enable us to determine the necessary number and depth of boreholes. The determination of thermal conductivity of the soil in laboratory experiments does not usually coincide with the data under in-situ conditions. Therefore, an in-situ method of experimental determination of these parameters, the so-called thermal response test, is presented in this paper. In addition to the description of the experimental procedure and installation overview, the paper describes methods based on theory and presents their basic limitations, through the presentation of experimental data. [Acknowledgment. This paper is made in a scope of the project TR 33047 “Intelligent climate control systems to achieve energy efficient regime in the complex conditions of exploitation” funded by the Ministry of Education and Science of the Republic of Serbia.

  10. Multimodality comparison of quantitative volumetric analysis of the right ventricle.

    Science.gov (United States)

    Sugeng, Lissa; Mor-Avi, Victor; Weinert, Lynn; Niel, Johannes; Ebner, Christian; Steringer-Mascherbauer, Regina; Bartolles, Ralf; Baumann, Rolf; Schummers, Georg; Lang, Roberto M; Nesser, Hans-Joachim

    2010-01-01

    We undertook volumetric analysis of the right ventricle (RV) by real-time 3-dimensional echocardiography (RT3DE), cardiac magnetic resonance (CMR), and cardiac computed tomography (CCT) on images obtained in RV-shaped phantoms and in patients with a wide range of RV geometry. Assessment of the RV by 2-dimensional (2D) echocardiography remains challenging due to its unique geometry and limitations of the current analysis techniques. RT3DE, CMR, and CCT, which can quantify RV volumes, promise to overcome the limitations of 2D echocardiography. Images were analyzed using RV Analysis software. Volumes measured in vitro were compared with the true volumes. The human protocol included 28 patients who underwent RT3DE, CMR, and CT on the same day. Volumetric analysis of CMR images was used as a reference, against which RT3DE and CCT measurements were compared using linear regression and Bland-Altman analyses. To determine the reproducibility of the volumetric analysis, repeated measurements were performed for all 3 imaging modalities in 11 patients. The in vitro measurements showed that: 1) volumetric analysis of CMR images yielded the most accurate measurements; 2) CCT measurements showed slight (4%) but consistent overestimation; and 3) RT3DE measurements showed small underestimation, but considerably wider margins of error. In humans, both RT3DE and CCT measurements correlated highly with the CMR reference (r=0.79 to 0.89) and showed the same trends of underestimation and overestimation noted in vitro. All interobserver and intraobserver variability values were <14%, with those of CMR being the highest. Volumetric quantification of RV volume was performed on CMR, CCT, and RT3DE images. Eliminating analysis-related intermodality differences allowed fair comparisons and highlighted the unique limitations of each modality. Understanding these differences promises to aid in the functional assessment of the RV. Copyright (c) 2010 American College of Cardiology Foundation

  11. Comparative Study of the Volumetric Methods Calculation Using GNSS Measurements

    Science.gov (United States)

    Şmuleac, Adrian; Nemeş, Iacob; Alina Creţan, Ioana; Sorina Nemeş, Nicoleta; Şmuleac, Laura

    2017-10-01

    This paper aims to achieve volumetric calculations for different mineral aggregates using different methods of analysis and also comparison of results. To achieve these comparative studies and presentation were chosen two software licensed, namely TopoLT 11.2 and Surfer 13. TopoLT program is a program dedicated to the development of topographic and cadastral plans. 3D terrain model, level courves and calculation of cut and fill volumes, including georeferencing of images. The program Surfer 13 is produced by Golden Software, in 1983 and is active mainly used in various fields such as agriculture, construction, geophysical, geotechnical engineering, GIS, water resources and others. It is also able to achieve GRID terrain model, to achieve the density maps using the method of isolines, volumetric calculations, 3D maps. Also, it can read different file types, including SHP, DXF and XLSX. In these paper it is presented a comparison in terms of achieving volumetric calculations using TopoLT program by two methods: a method where we choose a 3D model both for surface as well as below the top surface and a 3D model in which we choose a 3D terrain model for the bottom surface and another 3D model for the top surface. The comparison of the two variants will be made with data obtained from the realization of volumetric calculations with the program Surfer 13 generating GRID terrain model. The topographical measurements were performed with equipment from Leica GPS 1200 Series. Measurements were made using Romanian position determination system - ROMPOS which ensures accurate positioning of reference and coordinates ETRS through the National Network of GNSS Permanent Stations. GPS data processing was performed with the program Leica Geo Combined Office. For the volumetric calculating the GPS used point are in 1970 stereographic projection system and for the altitude the reference is 1975 the Black Sea projection system.

  12. Experimental determination of the distributed dynamic coefficients for a hydrodynamic fluid film bearing

    Science.gov (United States)

    Gyurko, John Harrison

    Most current rotor bearing analysis utilizes lumped parameter bearing coefficients to model the static and dynamic characteristics of fluid film bearings. By treating the stiffness and damping properties of the fluid film as acting upon the axial centerline of the rotor, these models are limited in their analysis to first order lateral rotor-bearing motion. The development of numerical methods that distribute the dynamic properties of the fluid film around the bearing circumference allow for higher order analysis of the motion between the bearing and rotor. Assessment of the accuracy of the numerical method used to calculate distributed dynamic fluid film bearing coefficients is performed by developing a novel hydrodynamic journal bearing test rig and experimental testing procedure capable of obtaining measured distributed dynamic coefficients over a range of bearing operating conditions. The instrumented bearing test rig is used to measure the dynamic bearing displacement and fluid film pressure responses from application of an externally applied excitation force. Least squares solution to a system of perturbated pressure equations, populated by measured displacement and pressure responses, is used to determine the hydrodynamic stiffness and damping properties for a finite region of the bearing surface. Incremental rotation of pressure sensors embedded in the body of the test bearing allow for measurement of the fluid film circumferential pressure distribution which is used to calculate a set of experimentally determined dynamic bearing coefficients. Distributed bearing coefficients derived from experimental measurements are compared to numerically calculated distributed coefficients as well as to lumped parameter coefficients generated from experimental and numerical methods found in the literature. Overall, the numerically calculated distributed coefficients successfully model both the circumferential distribution and the operating conditions of the experimental

  13. Dual-gated volumetric modulated arc therapy

    International Nuclear Information System (INIS)

    Fahimian, Benjamin; Wu, Junqing; Wu, Huanmei; Geneser, Sarah; Xing, Lei

    2014-01-01

    Gated Volumetric Modulated Arc Therapy (VMAT) is an emerging radiation therapy modality for treatment of tumors affected by respiratory motion. However, gating significantly prolongs the treatment time, as delivery is only activated during a single respiratory phase. To enhance the efficiency of gated VMAT delivery, a novel dual-gated VMAT (DG-VMAT) technique, in which delivery is executed at both exhale and inhale phases in a given arc rotation, is developed and experimentally evaluated. Arc delivery at two phases is realized by sequentially interleaving control points consisting of MUs, MLC sequences, and angles of VMAT plans generated at the exhale and inhale phases. Dual-gated delivery is initiated when a respiration gating signal enters the exhale window; when the exhale delivery concludes, the beam turns off and the gantry rolls back to the starting position for the inhale window. The process is then repeated until both inhale and exhale arcs are fully delivered. DG-VMAT plan delivery accuracy was assessed using a pinpoint chamber and diode array phantom undergoing programmed motion. DG-VMAT delivery was experimentally implemented through custom XML scripting in Varian’s TrueBeam™ STx Developer Mode. Relative to single gated delivery at exhale, the treatment time was improved by 95.5% for a sinusoidal breathing pattern. The pinpoint chamber dose measurement agreed with the calculated dose within 0.7%. For the DG-VMAT delivery, 97.5% of the diode array measurements passed the 3%/3 mm gamma criterion. The feasibility of DG-VMAT delivery scheme has been experimentally demonstrated for the first time. By leveraging the stability and natural pauses that occur at end-inspiration and end-exhalation, DG-VMAT provides a practical method for enhancing gated delivery efficiency by up to a factor of two

  14. Experimental and numerical determination of temperature gradients for a single tube alkali metal thermal-to-electric converter cell

    Science.gov (United States)

    Wright, S.

    2001-01-01

    This paper presents the results from the experimental and numerical determination of shell temperature gradients for a single tube AMTEC cell evaluated under simulated deep space operating conditions.

  15. Determination of a non-measurable quantity using information from calculations and experimental measurements: application to the damage rate determination

    Science.gov (United States)

    Bourganel, Stéphane; Nimal, Jean-Claude

    2017-09-01

    This article presents a method dedicated to the determination of the best value of a required quantity which is estimated by calculation, using information closely related, obtained by measurements and calculations. This best value, called thereafter the "target", is not measurable in most cases. DPA and high energy neutron fluence (typically higher than 1 MeV) involved in vessel surveillance programs, using measurements of dosimeters, are some examples of application of this methodology. This methodology is applied without spectrum adjustment, but the spectrum shape is implicitly taken into account. In this article, an example is presented based on the FLUOLE-2 experimental program, which is developed and conducted by CEA. Neutron information is derived from a set of different kinds of neutron dosimeters. The objective is to estimate the best value of reaction rate values for each kind of dosimeters. All calculations are carried out using TRIPOLI-4 3D pointwise Monte Carlo code, and DARWIN/PEPIN2 depletion code.

  16. Hologlyphics: volumetric image synthesis performance system

    Science.gov (United States)

    Funk, Walter

    2008-02-01

    This paper describes a novel volumetric image synthesis system and artistic technique, which generate moving volumetric images in real-time, integrated with music. The system, called the Hologlyphic Funkalizer, is performance based, wherein the images and sound are controlled by a live performer, for the purposes of entertaining a live audience and creating a performance art form unique to volumetric and autostereoscopic images. While currently configured for a specific parallax barrier display, the Hologlyphic Funkalizer's architecture is completely adaptable to various volumetric and autostereoscopic display technologies. Sound is distributed through a multi-channel audio system; currently a quadraphonic speaker setup is implemented. The system controls volumetric image synthesis, production of music and spatial sound via acoustic analysis and human gestural control, using a dedicated control panel, motion sensors, and multiple musical keyboards. Music can be produced by external acoustic instruments, pre-recorded sounds or custom audio synthesis integrated with the volumetric image synthesis. Aspects of the sound can control the evolution of images and visa versa. Sounds can be associated and interact with images, for example voice synthesis can be combined with an animated volumetric mouth, where nuances of generated speech modulate the mouth's expressiveness. Different images can be sent to up to 4 separate displays. The system applies many novel volumetric special effects, and extends several film and video special effects into the volumetric realm. Extensive and various content has been developed and shown to live audiences by a live performer. Real world applications will be explored, with feedback on the human factors.

  17. Experimental determination of neutron capture cross sections of fast reactor structure materials integrated in intermediate energy spectra. Vol. 2: description of experimental structure

    International Nuclear Information System (INIS)

    Tassan, S.

    1978-01-01

    A selection of technical documents is given concerning the experimental determination of the neutron capture cross-sections of fast reactor structural materials (Fe, Cr, Ni...) integrated over the intermediate energy spectra. The experimental structure project and modifications of the reactor RB2 for this experiment, together with criticality and safety calculations, are presented

  18. Calculation of a new Meeh constant and experimental determination of burn size.

    Science.gov (United States)

    Gilpin, D A

    1996-12-01

    With advances in research techniques involving molecular biology, the need for precision in the determination of surface area is even greater than previously. This study sets out to determine the most accurate Meeh constant, k, for a commonly used weight range of experimental rats. The importance of a narrow weight range is appreciated and planometric data is presented from a series of adolescent rats that allow a new k value to be calculated. The figures presented here represent the largest number of animals, of a commonly used rat strain, in the most widely used weight range yet described. Pelts were removed from 16 anaesthetized male Sprague-Dawley rats after cervical dislocation. For each animal total body surface area (TBSA) was determined planometrically, along with premarked areas on the dorsal and ventral surfaces. Entering the planometrically measured data along with the animal's weight into the Meeh formula, a k value was obtained for each rat. Surface areas were then calculated for each animal using the mean k, 9.46, and compared against figures obtained by using historical values for the Meeh constant. Using the new k value a method is described for the accurate determination of total body surface area and premarked surface areas, in experimental rats of a specific weight range.

  19. Osmotic coefficients of alcoholic mixtures containing BMpyrDCA: Experimental determination and correlation

    International Nuclear Information System (INIS)

    Calvar, N.; Domínguez, Á.; Macedo, E.A.

    2014-01-01

    Graphical abstract: - Highlights: • Osmotic coefficients of alcohols with BMpyrDCA ionic liquid are determined. • Experimental data were correlated with Extended Pitzer model of Archer and MNRTL. • Mean molal activity coefficients and excess Gibbs free energies were calculated. • The results have been interpreted in terms of interactions. - Abstract: The vapour pressure osmometry technique (VPO) has been used to obtain the osmotic coefficients of the binary mixtures of the primary and secondary alcohols 1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol with the ionic liquid 1-butyl-1-methylpyrrolidinium dicyanamide, BMpyrDCA. From these coefficients, the corresponding activity coefficients and vapour pressures of the mixtures have been also determined. The results have been discussed in terms of solute–solvent and ion–ion interactions and have been compared with those taken from literature in order to analyse the influence of the anion or cation constituting the ionic liquid. For the treatment of the experimental data, the Extended Pitzer model of Archer and the MNRTL model have been applied, obtaining standard deviations from the experimental osmotic coefficients lower than 0.015 and 0.065, respectively. From the parameters obtained with the Extended Pitzer model or Archer, the mean molal activity coefficients and the excess Gibbs free energy for the studied mixtures have been calculated

  20. Experimental determinations of the eigenmodes for composite bars made with carbon and Kevlar-carbon fibers

    Science.gov (United States)

    Miriţoiu, C. M.; Stănescu, M. M.; Burada, C. O.; Bolcu, D.; Roşca, V.

    2015-11-01

    For modal identification, the single-point excitation method has been widely used in modal tests and it consists in applying a force in a given point and recording the vibratory structure response in all interest points, including the excitation point. There will be presented the experimental recordings for the studied bars (with Kevlar-carbon or carbon fibers), the frequency response function in Cartesian and polar coordinates. By using the frequency response functions we determine the eigenparameters for each bar. We present the final panel of the eigenmodes (with the damping factors, eigenfrequencies and critical damping) for each considered bar. Using the eigenfrequency of the first determined eigenmode, the bars stiffness has been determined. The presented bars can be used in practical engineering for: car or bus body parts, planes body parts, bullet-proof vests, reinforcements for sandwich beams, and so on.

  1. Experimental determination of the empirical formula and energy content of unknown organics in waste streams

    International Nuclear Information System (INIS)

    Shizas, I.; Kosmatos, A.; Bagley, D.M.

    2002-01-01

    Two experimental methods are described in this paper: one for determining the empirical formula, and one for determining the energy content of unknown organics in waste streams. The empirical formula method requires volatile solids (VS), chemical oxygen demand (COD), total organic carbon (TOC), and total Kjeldahl nitrogen (TKN) to be measured for the waste; the formula can then be calculated from these values. To determine the energy content of the organic waste, bomb calorimetry was used with benzoic acid as a combustion aid. The results for standard compounds (glucose, propionic acid, L-arginine, and benzoic acid) were relatively good. The energy content measurement for wastewater and sludges had good reproducibility (i.e. 1.0 to 3.2% relative standard deviation for triplicate samples). Trouble encountered in the measurement of the empirical formulae of the waste samples was possibly due to difficulties with the TOC test; further analysis of this is required. (author)

  2. EXPERIMENTAL DETERMINATION OF LONGITUDINAL COMPONENT OF MAGNETIC FLUX IN FERROMAGNETIC WIRE OF SINGLE-CORE POWER CABLE ARMOUR

    Directory of Open Access Journals (Sweden)

    I.A. Kostiukov

    2014-12-01

    Full Text Available A problem of determination of effective longitudinal magnetic permeability of single core power cable armour is defined. A technique for experimental determination of longitudinal component of magnetic flux in armour spiral ferromagnetic wire is proposed.

  3. Mass and position determination in MEMS mass sensors: a theoretical and an experimental investigation

    KAUST Repository

    Bouchaala, Adam M.

    2016-08-31

    We present a method to determine accurately the position and mass of an entity attached to the surface of an electrostatically actuated clamped-clamped microbeam implemented as a mass sensor. In the theoretical investigation, the microbeam is modeled as a nonlinear Euler-Bernoulli beam and a perturbation technique is used to develop a closed-form expression for the frequency shift due to an added mass at a specific location on the microbeam surface. The experimental investigation was conducted on a microbeam made of Polyimide with a special lower electrode to excite both of the first and second modes of vibration. Using an ink-jet printer, we deposited droplets of polymers with a defined mass and position on the surface of the microbeam and we measured the shifts in its resonance frequencies. The theoretical predictions of the mass and position of the deposited droplets match well with the experimental measurements.

  4. Mass and Position Determination in MEMS Resonant Mass Sensors: Theoretical and Experimental Investigation

    KAUST Repository

    Bouchaala, Adam M.

    2016-12-05

    We present a method to determine accurately the position and mass of an entity attached to the surface of an electrostatically actuated clamped-clamped microbeam implemented as a mass sensor. In the theoretical investigation, the microbeam is modeled as a nonlinear Euler-Bernoulli beam and a perturbation technique is used to develop a closed-form expression for the frequency shift due to an added mass at a specific location on the microbeam surface. The experimental investigation was conducted on a microbeam made of Polyimide with a special lower electrode to excite both of the first and second modes of vibration. Using an ink-jet printer, we deposited droplets of polymers with a defined mass and position on the surface of the microbeam and we measured the shifts in its resonance frequencies. The theoretical predictions of the mass and position of the deposited droplets match well with the experimental measurements.

  5. Determining the parity of a permutation using an experimental NMR qutrit

    International Nuclear Information System (INIS)

    Dogra, Shruti; Arvind,; Dorai, Kavita

    2014-01-01

    We present the NMR implementation of a recently proposed quantum algorithm to find the parity of a permutation. In the usual qubit model of quantum computation, it is widely believed that computational speedup requires the presence of entanglement and thus cannot be achieved by a single qubit. On the other hand, a qutrit is qualitatively more quantum than a qubit because of the existence of quantum contextuality and a single qutrit can be used for computing. We use the deuterium nucleus oriented in a liquid crystal as the experimental qutrit. This is the first experimental exploitation of a single qutrit to carry out a computational task. - Highlights: • NMR implementation of a quantum algorithm to determine the parity of a permutation. • Algorithm implemented on a single qutrit. • Computational speedup achieved without quantum entanglement. • Single qutrit shows quantum contextuality

  6. Experimental determination of void fraction in surface aeration using image processing technique

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadpur, Amir; Akhavan-Behabadi, Mohammad Ali; Ebrahimzaedh, Masoud; Hanafizadeh, Pedram; Raisee, Mehrdad [University of Tehran, Tehran (Iran, Islamic Republic of)

    2015-06-15

    In this paper, a new method for determination of void fraction in surface aeration process is presented and discussed. The proposed method is based on the image processing technique. The experimental setup has been designed to create various surface aeration conditions in the water. Void fraction has been calculated for the wide range of water height, impeller immersion depth and rotational speed. Experiments have been performed in an open cubic tank with side length of 60 cm, equipped with one Rushton disk turbine. Moreover, the void fraction has been measured with level gauge method. The results showed that the image processing technique provides more accurate results than the level gauge measurements for void fraction calculation in surface aeration especially in low void fraction aeration. In addition, the experimental data revealed that increase in impeller immersion depth and rotational speed increase void fraction and oxygen transfer rate in surface aeration process.

  7. EXPERIMENTAL DETERMINATION OF DOUBLE VIBE FUNCTION PARAMETERS IN DIESEL ENGINES WITH BIODIESEL

    Directory of Open Access Journals (Sweden)

    Radivoje B Pešić

    2010-01-01

    Full Text Available A zero-dimensional, one zone model of engine cycle for steady-state regimes of engines and a simplified procedure for indicator diagrams analysis have been developed at the Laboratory for internal combustion engines, fuels and lubricants of the Faculty of Mechanical Engineering in Kragujevac. In addition to experimental research, thermodynamic modeling of working process of diesel engine with direct injection has been presented in this paper. The simplified procedure for indicator diagrams analysis has been applied, also. The basic problem, a selection of shape parameters of double Vibe function used for modeling the engine operation process, has been solved. The influence of biodiesel fuel and engine working regimes on the start of combustion, combustion duration and shape parameter of double Vibe was determined by a least square fit of experimental heat release curve.

  8. A new method for the experimental determination of three-phase relative permeabilities

    International Nuclear Information System (INIS)

    Perez Carrillo, Edgar Ricardo; Jose Francisco Zapata Arango; Santos Santos, Nicolas

    2008-01-01

    Petroleum reservoirs under primary, secondary or tertiary recovery processes usually experience simultaneous flow of three fluids phases (oil, water and gas). Reports on some mathematical models for calculating three-phase relative permeability are available in the Literature. Nevertheless, many of these models were designed based on certain experimental conditions and reservoir rocks and fluids. Therefore, special care has to be taken when applying them to specific reservoirs. At the laboratory level, three-phase relative permeability can be calculated using experimental unsteady-state or steady state methodologies. This paper proposes an unsteady-state methodology to evaluate three-phase relative permeability using the equipment available at the petrophysical analysis Laboratory of the Instituto Colombiano del Petroleo (ICP) of Ecopetrol S.A. Improvements to the equipment were effected in order to achieve accuracy in the unsteady-state measurement of three-phase relative permeability. The target of improvements was directed toward to the attainment of two objectives:1) the modification of the equipment to obtain more reliable experimental data and 2) the appropriate interpretation of the data obtained. Special attention was given to the differential pressure and uncertainty measurement in the determination of fluid saturation in the rock samples. Three experiments for three-phase relative permeability were conducted using a sample A and reservoir rock from the Colombian Foothills. Fluid tests included the utilization of synthetic brine, mineral oil, reservoir crude oil and nitrogen. Two runs were conducted at the laboratory conditions while one run was conducted at reservoir conditions. Experimental results of these tests were compared using 16 mathematical models of three-phase relative permeability. For the three-phase relative permeability to oil, the best correlations between experimental data and tests using Blunt, Hustad Hasen, and Baker's models were

  9. Determination of hydroxy acids in cosmetics by chemometric experimental design and cyclodextrin-modified capillary electrophoresis.

    Science.gov (United States)

    Liu, Pei-Yu; Lin, Yi-Hui; Feng, Chia Hsien; Chen, Yen-Ling

    2012-10-01

    A CD-modified CE method was established for quantitative determination of seven hydroxy acids in cosmetic products. This method involved chemometric experimental design aspects, including fractional factorial design and central composite design. Chemometric experimental design was used to enhance the method's separation capability and to explore the interactions between parameters. Compared to the traditional investigation that uses multiple parameters, the method that used chemometric experimental design was less time-consuming and lower in cost. In this study, the influences of three experimental variables (phosphate concentration, surfactant concentration, and methanol percentage) on the experimental response were investigated by applying a chromatographic resolution statistic function. The optimized conditions were as follows: a running buffer of 150 mM phosphate solution (pH 7) containing 0.5 mM CTAB, 3 mM γ-CD, and 25% methanol; 20 s sample injection at 0.5 psi; a separation voltage of -15 kV; temperature was set at 25°C; and UV detection at 200 nm. The seven hydroxy acids were well separated in less than 10 min. The LOD (S/N = 3) was 625 nM for both salicylic acid and mandelic acid. The correlation coefficient of the regression curve was greater than 0.998. The RSD and relative error values were all less than 9.21%. After optimization and validation, this simple and rapid analysis method was considered to be established and was successfully applied to several commercial cosmetic products. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Volumetric Echocardiographic Particle Image Velocimetry (V-Echo-PIV)

    Science.gov (United States)

    Falahatpisheh, Ahmad; Kheradvar, Arash

    2015-11-01

    Measurement of 3D flow field inside the cardiac chambers has proven to be a challenging task. Current laser-based 3D PIV methods estimate the third component of the velocity rather than directly measuring it and also cannot be used to image the opaque heart chambers. Modern echocardiography systems are equipped with 3D probes that enable imaging the entire 3D opaque field. However, this feature has not yet been employed for 3D vector characterization of blood flow. For the first time, we introduce a method that generates velocity vector field in 4D based on volumetric echocardiographic images. By assuming the conservation of brightness in 3D, blood speckles are tracked. A hierarchical 3D PIV method is used to account for large particle displacement. The discretized brightness transport equation is solved in a least square sense in interrogation windows of size 163 voxels. We successfully validate the method in analytical and experimental cases. Volumetric echo data of a left ventricle is then processed in the systolic phase. The expected velocity fields were successfully predicted by V-Echo-PIV. In this work, we showed a method to image blood flow in 3D based on volumetric images of human heart using no contrast agent.

  11. Why Students Fail at Volumetric Analysis.

    Science.gov (United States)

    Pickering, Miles

    1979-01-01

    Investigates the reasons for students' failure in an introductory volumetric analysis course by analyzing test papers and judging them against a hypothetical ideal method of grading laboratory techniques. (GA)

  12. Experimental results to determine the separation performance of the packages used in cryogenic distillation isotopes

    International Nuclear Information System (INIS)

    Bornea, A.M.; Stefanescu, I.; Zamfirache, M.; Balteanu, O.; Preda, A.

    2007-01-01

    The cryogenic distillation of the hydrogen isotopes represents the back-end separation process most efficient and usually used in detritiation technologies. In our institute there were made many researches in the field of hydrogen isotopes separation. The first results were obtained based on an experimental installation - Pilot Plant for heavy water production - and in present days using a Detritiation Pilot Plant. In our Institute, was manufactured and patented a lot of hydrophilic package for isotopic distillation of water and hydrogen and also catalysts used for isotopic exchange waterhydrogen. This items was continuously developed in order to increase the isotopic separation efficiency. The goal of this paper is to determine by experimental work the performance of the package manufactured in our institute used in the cryogenic distillation process. To describe the separation performances was developed a mathematical model for the cryogenic distillation of the hydrogen isotopes. In order to determine the characteristics of the package, the installation was operated in the total reflux mode, for different flow rate for the liquid. There were made several experiments considering different operating conditions corresponding to various values for the refrigeration power in the column condenser. From the bottom and the top of the distillation column there were extracted samples in order to determine the isotopic composition. Processing the experimental data obtained from these tests using the Fenske relation, we obtained the separation efficiency function of the power inside the column boiler, operating pressure and also pressure drop along the package. This efficiency is describe by the number of theoretical plates per meter (NTT/m) or by equivalent height of one theoretical plate (IETT). (orig.)

  13. EXPERIMENTAL DETERMINATION OF TEMPERATURES IN SPARK GENERATED BUBBLES OSCILLATING IN WATER

    Directory of Open Access Journals (Sweden)

    Karel Vokurka

    2017-05-01

    Full Text Available The surface temperatures of the plasma core in the final stages of the first contraction phase of spark-generated bubbles oscillating under ordinary laboratory conditions in a large expanse of water are determined experimentally. The measurement method is based on an analysis of the optical radiation from the bubbles and on the assumption that the plasma core is radiating as a black-body. It is found that the maximum surface temperatures of the plasma core range 4300–8700 K.

  14. Experimental determination of isotope enrichment factors – bias from mass removal by repetitive sampling

    DEFF Research Database (Denmark)

    Buchner, Daniel; Jin, Biao; Ebert, Karin

    2017-01-01

    . Application of inappropriate methods may lead to incorrect and inconsistent ε-values entailing misinterpretations regarding the processes underlying isotope fractionation. In fact, our results suggest that artifacts arising from inappropriate data evaluation might contribute to the variability of published ε......Application of compound-specific stable isotope approaches often involves comparisons of isotope enrichment factors (ε). Experimental determination of ε-values is based on the Rayleigh equation, which relates the change in measured isotope ratios to the decreasing substrate fractions and is valid...

  15. Comparison of experimental methods for determination of dynamic properties of viscoelastic material

    Science.gov (United States)

    Yam, L. H.; Kong, Leung H.; Wah, Lee W.; Fai, Fung K.

    1993-09-01

    Four experimental methods for determination of dynamic mechanical properties of viscoelastic materials are presented. The first and the second ones are the strain and acceleration measurement at two different crosssections of an axially impacted rod specimen respectively. The third method adopts resonance technique and the fourth one is correction method. Tests are carried out with Nylon 6 and Polyurethane(pU) . The diagrams of complex Young''s modulus and loss factor versus frequency are obtained. Comparison shows that the results from these four methods are reasonably close. The useful frequency ranges for valid results for each method are discussed.

  16. Determination of scatter fractions of some materials by experimental studies and Monte Carlo calculations

    CERN Document Server

    Meric, N; Bor, D

    1999-01-01

    Scatter fractions have been determined experimentally for lucite, polyethylene, polypropylene, aluminium and copper of varying thicknesses using a polyenergetic broad X-ray beam of 67 kVp. Simulation of the experiment has been carried out by the Monte Carlo technique under the same input conditions. Comparison of the measured and predicted data with each other and with the previously reported values has been given. The Monte Carlo calculations have also been carried out for water, bakelite and bone to examine the dependence of scatter fraction on the density of the scatterer.

  17. Is the thermal-spike model consistent with experimentally determined electron temperature?

    International Nuclear Information System (INIS)

    Ajryan, Eh.A.; Fedorov, A.V.; Kostenko, B.F.

    2000-01-01

    Carbon K-Auger electron spectra from amorphous carbon foils induced by fast heavy ions are theoretically investigated. The high-energy tail of the Auger structure showing a clear projectile charge dependence is analyzed within the thermal-spike model framework as well as in the frame of another model taking into account some kinetic features of the process. A poor comparison results between theoretically and experimentally determined temperatures are suggested to be due to an improper account of double electron excitations or due to shake-up processes which leave the system in a more energetic initial state than a statically screened core hole

  18. Quantitative analysis of fish wake dynamics using volumetric PIV data

    Science.gov (United States)

    Mendelson, Leah; Techet, Alexandra

    2013-11-01

    In the study of swimming hydrodynamics, the fluid impulse in the wake is used to quantify the momentum transferred by the fish as it swims. This impulse is typically computed from planar PIV measurements of the wake circulation and geometry by assuming an axisymmetric vortex ring model. However, in many propulsive and maneuvering scenarios, three-dimensional effects are of substantial importance, and wake features are not often an isolated, symmetric vortex ring. Volumetric PIV data provides a complete measure of the vortex geometry and orientation, and circulation can be determined over multiple planar slices through the volume. Using sample datasets obtained from synthetic aperture PIV (SAPIV), we demonstrate how the availability of volumetric PIV data enables more detailed analysis of hydrodynamic impulse and characterize the uncertainty created by planar measurements. Special attention is paid to unsteady maneuvering behaviors that generate asymmetric and linked wake features.

  19. Experimental Method for Determination of Self-Heating at the Point of Measurement

    Science.gov (United States)

    Sestan, D.; Zvizdic, D.; Grgec-Bermanec, L.

    2017-09-01

    This paper presents a new experimental method and algorithm for the determination of self-heating of platinum resistance thermometer (PRT) when the temperature instability of medium of interest would prevent an accurate self-heating determination using standard methods. In temperature measurements performed by PRT, self-heating is one of the most common sources of error and arises from the increase in sensor temperature caused by the dissipation of electrical heat when measurement current is applied to the temperature sensing element. This increase depends mainly on the applied current and the thermal resistances between thermometer sensing element and the environment surrounding the thermometer. The method is used for determination of self-heating of a 100 Ω industrial PRT which is intended for measurement of air temperature inside the saturation chamber of the primary dew/frost point generator at the Laboratory for Process Measurement (HMI/FSB-LPM). Self-heating is first determined for conditions present during the comparison calibration of the thermometer, using the calibration bath. The measurements were then repeated with thermometer being placed in an air stream inside the saturation chamber. The experiment covers the temperature range between -65°C and 10°C. Self-heating is determined for two different air velocities and two different vertical positions of PRT in relation to the chamber bottom.

  20. Experimental determination of viscosity of water based magnetite nanofluid for application in heating and cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Toghraie, Davood; Alempour, Seyed Mohammadbagher [Department of Mechanical Engineering, Khomeinishahr Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Afrand, Masoud, E-mail: masoud.afrand@pmc.iaun.ac.ir [Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Najafabad (Iran, Islamic Republic of)

    2016-11-01

    In this paper, experimental determination of dynamic viscosity of water based magnetite nanofluid (Fe{sub 3}O{sub 4}/water) was performed. The viscosity was measured in the temperature range of 20–55 °C for various samples with solid volume fractions of 0.1%, 0.2%, 0.4%, 1%, 2% and 3%. The results showed that the viscosity considerably decreases with increasing temperature. Moreover, the viscosity enhances with an increase in the solid volume fraction, remarkably. The calculated viscosity ratios showed that the maximum viscosity enhancement was 129.7%. Using experimental data, a new correlation has been proposed to predict the viscosity of magnetite nanofluid (Fe{sub 3}O{sub 4}/water). A comparison between the experimental results and the correlation outputs showed that the proposed model has a suitable accuracy. - Highlights: • Preparing Magnetite nanofluids with solid volume fractions up to 3%. • Measuring viscosity in temperature range of 20–55 °C using Brookfield Viscometer. • Maximum viscosity enhancement occurred at volume fraction of 3% and was 129.7%. • Proposing new correlation to predict the viscosity of Fe3O4/water nanofluid.

  1. Experimental investigation of surface determination process on multi-material components for dimensional computed tomography

    DEFF Research Database (Denmark)

    Borges de Oliveira, Fabrício; Stolfi, Alessandro; Bartscher, Markus

    2016-01-01

    and suitable surface determination settings, limits a better acceptance of CT as a CMS. Moreover, standard CT users are subject to the algorithms and boundary conditions implied by the use of commercial analysis software. In this context, this paper is concerned with the experimental evaluation...... of the influence of surface determination process on multi-material measurements, using functions available in the commercial CT data analysis software Volume Graphics VGStudio Max 2.2.6. Calibrated step gauges made of different materials, i.e. PEEK, PPS, and Al were used as reference standards. The step gauges...... were assembled in such a way as to have different multi-material X-ray absorption ratios. Comparative measurements of mono-material assemblies were performed as well. Different segmentation processes were considered (e.g. ISO-50%, local threshold, region growing, etc.), patch-based bidirectional length...

  2. Experimental procedures for the calibration of scintillation cells used in the determination of radon gas concentrations

    International Nuclear Information System (INIS)

    Grenier, M; Bigu, J.

    1982-02-01

    Experimental and analytical procedures are described for the calibration of scintillation cells used for the determination of radon gas concentration. In-house designed and built scintillation cells, used routinely in the monitoring of radon gas in uranium mine underground environments and in the laboratory, were calibrated. The cells had a volume of approximately 158 cm 3 and an α-counting efficiency ranging from 50% to 64%. Calibration factors for the cells were determined. Values ranged approximately from 0.177 cpm/pCiL -1 (4.77 cpm/BqL -1 ) to 0.224 cpm/pCiL -1 (6.05 cpm/BqL -1 ). The calibration facilities at the Elliot Lake Laboratory are briefly described

  3. Experimental determination of the average energy necessary for the production of an ion pair in air

    International Nuclear Information System (INIS)

    Guiho, J.P.; Simoen, J.P.

    1975-01-01

    The determination of the average energy Wbarsub(a) necessary to form an ion pair in air in a 60 Co beam (which is one of the French primary references in dosimetry) is obtained from measurements of the exposure and absorbed doses from the beam in the center of a graphite disc. The differential flux density of the beam having been measured the experimental value of Wbarsub(a) is obtained for a mean real photon energy. The so determined value of Wbarsub(a) in dry air is: Wbarsub(a) = 33,96 +-0.34 JC -1 for Ebar = 1150 keV. This result is then compared to different published values. From this comparison the importance of different correcting terms such as the air humidity correction and the carbon/air stopping power ratio, which constitutes the main source of uncertainty, are considered. (author)

  4. Experimental and predicted volumetric and refractive index properties of ternary mixtures of iodoethane with toluene and alcohols at temperature 298.15K and pressure 101kPa

    International Nuclear Information System (INIS)

    Atik, Zadjia

    2006-01-01

    Excess molar volumes V m E and change in refractive indices Δ mix n of the binary mixtures of (toluene+methanol) (toluene+ethanol) (toluene+1-propanol) (toluene+iodoethane) (methanol+iodoethane) (ethanol+iodoethane) (1-propanol+iodoethane), and the ternary mixtures of (toluene+methanol+iodoethane) (toluene+ethanol+iodoethane), and (toluene+1-propanol+iodoethane) were measured with vibrating-tube densimeters and an Abbe-type refractometer at the temperature 298.15K and the pressure 101kPa. The experimental V m E and Δ mix n values of the ternary systems were predicted by empirical equations using binary solution data

  5. Comparison of experimentally and theoretically determined radiation characteristics of photosynthetic microorganisms

    Science.gov (United States)

    Kandilian, Razmig; Pruvost, Jérémy; Artu, Arnaud; Lemasson, Camille; Legrand, Jack; Pilon, Laurent

    2016-05-01

    This paper aims to experimentally and directly validate a recent theoretical method for predicting the radiation characteristics of photosynthetic microorganisms. Such predictions would facilitate light transfer analysis in photobioreactors (PBRs) to control their operation and to maximize their production of biofuel and other high-value products. The state of the art experimental method can be applied to microorganisms of any shape and inherently accounts for their non-spherical and heterogeneous nature. On the other hand, the theoretical method treats the microorganisms as polydisperse homogeneous spheres with some effective optical properties. The absorption index is expressed as the weighted sum of the pigment mass absorption cross-sections and the refractive index is estimated based on the subtractive Kramers-Kronig relationship given an anchor refractive index and wavelength. Here, particular attention was paid to green microalgae Chlamydomonas reinhardtii grown under nitrogen-replete and nitrogen-limited conditions and to Chlorella vulgaris grown under nitrogen-replete conditions. First, relatively good agreement was found between the two methods for determining the mass absorption and scattering cross-sections and the asymmetry factor of both nitrogen-replete and nitrogen-limited C. reinhardtii with the proper anchor point. However, the homogeneous sphere approximation significantly overestimated the absorption cross-section of C. vulgaris cells. The latter were instead modeled as polydisperse coated spheres consisting of an absorbing core containing pigments and a non-absorbing but strongly refracting wall made of sporopollenin. The coated sphere approximation gave good predictions of the experimentally measured integral radiation characteristics of C. vulgaris. In both cases, the homogeneous and coated sphere approximations predicted resonance in the scattering phase function that were not observed experimentally. However, these approximations were

  6. Determination of Soil Moisture Content using Laboratory Experimental and Field Electrical Resistivity Values

    Science.gov (United States)

    Hazreek, Z. A. M.; Rosli, S.; Fauziah, A.; Wijeyesekera, D. C.; Ashraf, M. I. M.; Faizal, T. B. M.; Kamarudin, A. F.; Rais, Y.; Dan, M. F. Md; Azhar, A. T. S.; Hafiz, Z. M.

    2018-04-01

    The efficiency of civil engineering structure require comprehensive geotechnical data obtained from site investigation. In the past, conventional site investigation was heavily related to drilling techniques thus suffer from several limitations such as time consuming, expensive and limited data collection. Consequently, this study presents determination of soil moisture content using laboratory experimental and field electrical resistivity values (ERV). Field and laboratory electrical resistivity (ER) test were performed using ABEM SAS4000 and Nilsson400 soil resistance meter. Soil sample used for resistivity test was tested for characterization test specifically on particle size distribution and moisture content test according to BS1377 (1990). Field ER data was processed using RES2DINV software while laboratory ER data was analyzed using SPSS and Excel software. Correlation of ERV and moisture content shows some medium relationship due to its r = 0.506. Moreover, coefficient of determination, R2 analyzed has demonstrate that the statistical correlation obtain was very good due to its R2 value of 0.9382. In order to determine soil moisture content based on statistical correlation (w = 110.68ρ-0.347), correction factor, C was established through laboratory and field ERV given as 19.27. Finally, this study has shown that soil basic geotechnical properties with particular reference to water content was applicably determined using integration of laboratory and field ERV data analysis thus able to compliment conventional approach due to its economic, fast and wider data coverage.

  7. Bias determination for space accelerometers using the ZARM Catapult system - experimental setup and data analysis

    Science.gov (United States)

    Selig, Hanns; Santos Rodrigues, Manuel; Touboul, Pierre; Liorzou, Françoise

    2012-07-01

    Accelerometers for space applications - like the electrostatic differential accelrometer for the MICROSCOPE mission for testing the equivalence principle in space - have to be tested and qualified in μg-conditions in order to demonstrate the system operation and to determine the characteristic sensor parameters. One important characteristic property is the sensor bias. In principle one can determine the sensor bias directly by using the ZARM catapult system as test platform. Even in the evacuated drop tube the residual air pressure results in an air friction that depends on the capsule velocity. At the apex (highest point of the capsule trajectory) the acceleration (relative to the gravitational acceleration g) becomes zero due to the zero velocity at the apex. The direct measurement of the vertical linear acceleration sensor bias is affected by some additional effects that have to be understood in order to be able to determine the sensor bias. Two catapult campaigns have been carried out to demonstrate the principles of the bias determination using a SuperStar accelerometer (Onera). The presentation gives an overview on the experimental setup and on the corresponding data analysis.

  8. Experimental determination of optimal clamping torque for AB-PEM Fuel cell

    Directory of Open Access Journals (Sweden)

    Noor Ul Hassan

    2016-04-01

    Full Text Available Polymer electrolyte Membrane (PEM fuel cell is an electrochemical device producing electricity by the reaction of hydrogen and oxygen without combustion. PEM fuel cell stack is provided with an appropriate clamping torque to prevent leakage of reactant gases and to minimize the contact resistance between gas diffusion media (GDL and bipolar plates. GDL porous structure and gas permeability is directly affected by the compaction pressure which, consequently, drastically change the fuel cell performance. Various efforts were made to determine the optimal compaction pressure and pressure distributions through simulations and experimentation. Lower compaction pressure results in increase of contact resistance and also chances of leakage. On the other hand, higher compaction pressure decreases the contact resistance but also narrows down the diffusion path for mass transfer from gas channels to the catalyst layers, consequently, lowering cell performance. The optimal cell performance is related to the gasket thickness and compression pressure on GDL. Every stack has a unique assembly pressure due to differences in fuel cell components material and stack design. Therefore, there is still need to determine the optimal torque value for getting the optimal cell performance. This study has been carried out in continuation of deve­lopment of Air breathing PEM fuel cell for small Unmanned Aerial Vehicle (UAV application. Compaction pressure at minimum contact resistance was determined and clamping torque value was calcu­la­ted accordingly. Single cell performance tests were performed at five different clamping torque values i.e 0.5, 1.0, 1.5, 2.0 and 2.5 N m, for achieving optimal cell per­formance. Clamping pressure distribution tests were also performed at these torque values to verify uniform pressure distribution at optimal torque value. Experimental and theoretical results were compared for making inferences about optimal cell perfor­man­ce. A

  9. Integrated modeling and experimental approach for determining transcription factor profiles from fluorescent reporter data

    Directory of Open Access Journals (Sweden)

    Jayaraman Arul

    2008-07-01

    Full Text Available Abstract Background The development of quantitative models of signal transduction, as well as parameter estimation to improve existing models, depends on the ability to obtain quantitative information about various proteins that are part of the signaling pathway. However, commonly-used measurement techniques such as Western blots and mobility shift assays provide only qualitative or semi-quantitative data which cannot be used for estimating parameters. Thus there is a clear need for techniques that enable quantitative determination of signal transduction intermediates. Results This paper presents an integrated modeling and experimental approach for quantitatively determining transcription factor profiles from green fluorescent protein (GFP reporter data. The technique consists of three steps: (1 creating data sets for green fluorescent reporter systems upon stimulation, (2 analyzing the fluorescence images to determine fluorescence intensity profiles using principal component analysis (PCA and K-means clustering, and (3 computing the transcription factor concentration from the fluorescence intensity profiles by inverting a model describing transcription, translation, and activation of green fluorescent proteins. We have used this technique to quantitatively characterize activation of the transcription factor NF-κB by the cytokine TNF-α. In addition, we have applied the quantitative NF-κB profiles obtained from our technique to develop a model for TNF-α signal transduction where the parameters were estimated from the obtained data. Conclusion The technique presented here for computing transcription factor profiles from fluorescence microscopy images of reporter cells generated quantitative data on the magnitude and dynamics of NF-κB activation by TNF-α. The obtained results are in good agreement with qualitative descriptions of NF-κB activation as well as semi-quantitative experimental data from the literature. The profiles computed from

  10. Mode Content Determination of Terahertz Corrugated Waveguides Using Experimentally Measured Radiated Field Patterns.

    Science.gov (United States)

    Jawla, Sudheer K; Nanni, Emilio A; Shapiro, Michael A; Woskov, Paul P; Temkin, Richard J

    2012-06-01

    This work focuses on the accuracy of the mode content measurements in an overmoded corrugated waveguide using measured radiated field patterns. Experimental results were obtained at 250 GHz using a vector network analyzer with over 70 dB of dynamic range. The intensity and phase profiles of the fields radiated from the end of the 19 mm diameter helically tapped brass waveguide were measured on planes at 7, 10, and 13 cm from the waveguide end. The measured fields were back propagated to the waveguide aperture to provide three independent estimates of the field at the waveguide exit aperture. Projecting that field onto the modes of the guide determined the waveguide mode content. The three independent mode content estimates were found to agree with one another to an accuracy of better than ±0.3%. These direct determinations of the mode content were compared with indirect measurements using the experimentally measured amplitude in three planes, with the phase determined by a phase retrieval algorithm. The phase retrieval technique using the planes at 7, 10, and 13 cm yielded a mode content estimate in excellent agreement, within 0.3%, of the direct measurements. Phase retrieval results using planes at 10, 20, and 30 cm were less accurate due to truncation of the measurement in the transverse plane. The reported measurements benefited greatly from a precise mechanical alignment of the scanner with respect to the waveguide axis. These results will help to understand the accuracy of mode content measurements made directly in cold test and indirectly in hot test using the phase retrieval technique.

  11. A practical method to determine the effective resolution in incoherent experimental electron tomography

    Energy Technology Data Exchange (ETDEWEB)

    Heidari Mezerji, Hamed, E-mail: Hamed.Heidari@ua.ac.be [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Van den Broek, Wouter; Bals, Sara [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

    2011-04-15

    It is not straightforward to determine resolution for a 3D reconstruction when performing an electron tomography experiment. Different contributions such as missing wedge and misalignment add up and often influence the final resolution in an anisotropic manner. The conventional resolution measures can not be used for all of the reconstruction techniques, especially for iterative techniques which are more commonly used for electron tomography in materials science. Here we define a quantitative resolution measure that determines the resolution in three orthogonal directions of the reconstruction. As an application we use this measure to determine the optimum number of simultaneous iterative reconstruction technique (SIRT) iterations to reconstruct the gold nanoparticles, based on a high angle annular dark field STEM (HAADF-STEM) tilt series. -- Research highlights: {yields} We developed a model-based resolution measure for experimental electron tomography. {yields} It measures the resolution along the main directions in the reconstruction. {yields} It is applied to nano-size gold particles reconstructed with SIRT and WBP. {yields} The method is space invariant and independent of the particle size. {yields} The method yields the optimal number of 'SIRT iterations'; 20 in our case.

  12. Prices need no preferences: social trends determine decisions in experimental markets for pain relief.

    Science.gov (United States)

    Vlaev, Ivo; Seymour, Ben; Chater, Nick; Winston, Joel S; Yoshida, Wako; Wright, Nicholas; Symmonds, Mkael; Dolan, Ray

    2014-01-01

    A standard view in health economics is that, although there is no market that determines the "prices" for health states, people can nonetheless associate health states with monetary values (or other scales, such as quality adjusted life year [QALYs] and disability adjusted life year [DALYs]). Such valuations can be used to shape health policy, and a major research challenge is to elicit such values from people; creating experimental "markets" for health states is a theoretically attractive way to address this. We explore the possibility that this framework may be fundamentally flawed-because there may not be any stable values to be revealed. Instead, perhaps people construct ad hoc values, influenced by contextual factors, such as the observed decisions of others. The participants bid to buy relief from equally painful electrical shocks to the leg and arm in an experimental health market based on an interactive second-price auction. Thirty subjects were randomly assigned to two experimental conditions where the bids by "others" were manipulated to follow increasing or decreasing price trends for one, but not the other, pain. After the auction, a preference test asked the participants to choose which pain they prefer to experience for a longer duration. Players remained indifferent between the two pain-types throughout the auction. However, their bids were differentially attracted toward what others bid for each pain, with overbidding during decreasing prices and underbidding during increasing prices. Health preferences are dissociated from market prices, which are strongly referenced to others' choices. This suggests that the price of health care in a free-market has the capacity to become critically detached from people's underlying preferences. 2014 APA, all rights reserved

  13. Experimental determination of the cost of lesion healing on Porites compressa growth

    Science.gov (United States)

    Jayewardene, D.

    2010-03-01

    The spotted puffer ( Arothron meleagris) commonly feeds on finger coral ( Porites compressa) on Hawaiian shallow reefs. The predation involves removal of branch tips, resulting in open lesions that, in the field, heal in little over a month. This study determined the cost of tissue regeneration across simulated bite scars on the growth of experimentally scarred P. compressa nubbins, of three different size classes (4, 2, 1 cm tall), in a controlled laboratory environment. The results indicate that inflicted P. compressa lesions heal completely within approximately 36 days, on even the smallest nubbins. While growth was slowed before lesions closed, the healing process did not appear to affect the longer-term growth of fragments. Successful regeneration of tissue may be explained by small lesion size, the high surface area to perimeter ratio of the lesions, and the location of lesions on the growing tips. The lack of impact on overall growth rate of experimental fragments indicates that under favorable conditions, P. compressa is resilient to predation.

  14. Experimental determination of the phase equilibria in the Co-Fe-Zr ternary system

    International Nuclear Information System (INIS)

    Wang, C.P.; Yu, Y.; Zhang, H.H.; Hu, H.F.; Liu, X.J.

    2011-01-01

    Research highlights: → We determined four isothermal sections of the Co-Fe-Zr system from 1000 o C to 1300 o C. → No ternary compound was found in the Co-Fe-Zr ternary system. → The solubility of Fe in the liquid phase at 1300 o C is extremely large. → The (Co, Fe) 2 Zr phase form the continuous solution from Co-Zr side to Fe-Zr side. → The solubility of Zr in the fcc (Co, Fe) phase is extremely small. - Abstract: The phase equilibria in the Co-Fe-Zr ternary system were investigated by means of optical microscopy (OM), electron probe microanalysis (EPMA), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) on equilibrated ternary alloys. Four isothermal sections of the Co-Fe-Zr ternary system at 1300 o C, 1200 o C, 1100 o C and 1000 o C were experimentally established. The experimental results indicate that (1) no ternary compound was found in this system; (2) the solubility of Fe in the liquid phase of the Co-rich corner at 1300 o C is extremely large; (3) the liquid phase in the Zr-rich corner and the (Co,Fe) 2 Zr phase form the continuous solid solutions from the Co-Zr side to the Fe-Zr side; (4) the solubility of Zr in the fcc (Co, Fe) phase is extremely small.

  15. Active machine learning-driven experimentation to determine compound effects on protein patterns

    Science.gov (United States)

    Naik, Armaghan W; Kangas, Joshua D; Sullivan, Devin P; Murphy, Robert F

    2016-01-01

    High throughput screening determines the effects of many conditions on a given biological target. Currently, to estimate the effects of those conditions on other targets requires either strong modeling assumptions (e.g. similarities among targets) or separate screens. Ideally, data-driven experimentation could be used to learn accurate models for many conditions and targets without doing all possible experiments. We have previously described an active machine learning algorithm that can iteratively choose small sets of experiments to learn models of multiple effects. We now show that, with no prior knowledge and with liquid handling robotics and automated microscopy under its control, this learner accurately learned the effects of 48 chemical compounds on the subcellular localization of 48 proteins while performing only 29% of all possible experiments. The results represent the first practical demonstration of the utility of active learning-driven biological experimentation in which the set of possible phenotypes is unknown in advance. DOI: http://dx.doi.org/10.7554/eLife.10047.001 PMID:26840049

  16. Combined Theoretical and Experimental Analysis of Processes Determining Cathode Performance in Solid Oxide Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Kukla, Maija M.; Kotomin, Eugene Alexej; Merkle, R.; Mastrikov, Yuri; Maier, J.

    2013-02-11

    Solid oxide fuel cells (SOFC) are under intensive investigation since the 1980’s as these devices open the way for ecologically clean direct conversion of the chemical energy into electricity, avoiding the efficiency limitation by Carnot’s cycle for thermochemical conversion. However, the practical development of SOFC faces a number of unresolved fundamental problems, in particular concerning the kinetics of the electrode reactions, especially oxygen reduction reaction. We review recent experimental and theoretical achievements in the current understanding of the cathode performance by exploring and comparing mostly three materials: (La,Sr)MnO3 (LSM), (La,Sr)(Co,Fe)O3 (LSCF) and (Ba,Sr)(Co,Fe)O3 (BSCF). Special attention is paid to a critical evaluation of advantages and disadvantages of BSCF, which shows the best cathode kinetics known so far for oxides. We demonstrate that it is the combined experimental and theoretical analysis of all major elementary steps of the oxygen reduction reaction which allows us to predict the rate determining steps for a given material under specific operational conditions and thus control and improve SOFC performance.

  17. Combined theoretical and experimental analysis of processes determining cathode performance in solid oxide fuel cells.

    Science.gov (United States)

    Kuklja, M M; Kotomin, E A; Merkle, R; Mastrikov, Yu A; Maier, J

    2013-04-21

    Solid oxide fuel cells (SOFC) are under intensive investigation since the 1980's as these devices open the way for ecologically clean direct conversion of the chemical energy into electricity, avoiding the efficiency limitation by Carnot's cycle for thermochemical conversion. However, the practical development of SOFC faces a number of unresolved fundamental problems, in particular concerning the kinetics of the electrode reactions, especially oxygen reduction reaction. We review recent experimental and theoretical achievements in the current understanding of the cathode performance by exploring and comparing mostly three materials: (La,Sr)MnO3 (LSM), (La,Sr)(Co,Fe)O3 (LSCF) and (Ba,Sr)(Co,Fe)O3 (BSCF). Special attention is paid to a critical evaluation of advantages and disadvantages of BSCF, which shows the best cathode kinetics known so far for oxides. We demonstrate that it is the combined experimental and theoretical analysis of all major elementary steps of the oxygen reduction reaction which allows us to predict the rate determining steps for a given material under specific operational conditions and thus control and improve SOFC performance.

  18. Implementation of experimental CRDS and DOAS systems for determination of gases with direct green house effect

    Science.gov (United States)

    Cotirlan, C.; Negrila, C. C.; Ristici, V.; Balin, I.

    2009-04-01

    The implementation of the experimental spectroscopic systems address stringent problems related to the control of gases emissions with direct green house effect as: CO2, CH4,NOx. CRDS (Cavity Ring - Down Spectroscopy) and DOAS (Differential Optical Absorption Spectroscopy) are versatile, fast-response techniques and can contribute to the improving of the quality of air, especially in large cities and industrial areas as well as the improving the meteorological prognosis. Firstly, we describe an CRD system for measurements of the optical absorption of water and for determination of the optical properties of gases with direct green house effect from ambient air. Secondly, a DOAS system provides measurements for the detection and characterization of atmospheric pollutants. The data obtained in the two systems: CRDS and DOAS are correlated in the aim of pollutant concentrations monitoring in different humidity conditions. The humidity is a main factor in the concentration and the dispersion of atmospheric pollutants. The analysis of how different compositions of pollutants answer to humidity have a significant impact upon the uncertainties regarding the modeling of pollutants impact on the climate. The potential of CRDS and DOAS techniques in the study of the environmental pollution and in the laboratory fundamental research is proved by their sensitivity better than 1 ppm. In addition to DOAS system, gases standards and calibrated established point monitors for SO2, NOx and O3 are integrated in the measurement approach and tests in order to validate our CRDS first experimental set-up.

  19. Improved morphed potentials for Ar-HBr including scaling to the experimentally determined dissociation energy.

    Science.gov (United States)

    Wang, Z; McIntosh, A L; McElmurry, B A; Walton, J R; Lucchese, R R; Bevan, J W

    2005-09-15

    A lead salt diode infrared laser spectrometer has been employed to investigate the rotational predissociation in Ar-HBr for transitions up to J' = 79 in the v(1) HBr stretching vibration of the complex using a slit jet and static gas phase. Line-shape analysis and modeling of the predissociation lifetimes have been used to determine a ground-state dissociation energy D(0) of 130(1) cm(-1). In addition, potential energy surfaces based on ab initio calculations are scaled, shifted, and dilated to generate three-dimensional morphed potentials for Ar-HBr that reproduce the measured value of D(0) and that have predictive capabilities for spectroscopic data with nearly experimental uncertainty. Such calculations also provide a basis for making a comprehensive comparison of the different morphed potentials generated using the methodologies applied.

  20. Building a substitute model of a bolster based on experimentally determined deflection

    Science.gov (United States)

    Zgoll, F.; Götze, T.; Volk, W.

    2017-09-01

    The high design requirements in the production of car body parts necessitate an exact closure of the forming tools in deep drawing processes. The tool closure is directly related to the machine elastic behaviour. To significantly reduce efforts and save time during ramp up of new forming tools, knowledge of the expected machine behaviour should be considered during the virtual development process of the tools. A prerequisite for that is building a validated machine-specific substitute model of the forming press composed of bolster, ram and drawing cushion. In this contribution, a substitute model with the help of finite element analysis (FEA) based on experimentally determined deflection is presented. The deflection measurements are performed by means of a multifunctional press measuring system from Volkswagen.

  1. Experimental validation of analytical models for a rapid determination of cycle parameters in thermoplastic injection molding

    Science.gov (United States)

    Pignon, Baptiste; Sobotka, Vincent; Boyard, Nicolas; Delaunay, Didier

    2017-10-01

    Two different analytical models were presented to determine cycle parameters of thermoplastics injection process. The aim of these models was to provide quickly a first set of data for mold temperature and cooling time. The first model is specific to amorphous polymers and the second one is dedicated to semi-crystalline polymers taking the crystallization into account. In both cases, the nature of the contact between the polymer and the mold could be considered as perfect or not (thermal contact resistance was considered). Results from models are compared with experimental data obtained with an instrumented mold for an acrylonitrile butadiene styrene (ABS) and a polypropylene (PP). Good agreements were obtained for mold temperature variation and for heat flux. In the case of the PP, the analytical crystallization times were compared with those given by a coupled model between heat transfer and crystallization kinetics.

  2. Three-dimensional FEM model of FBGs in PANDA fibers with experimentally determined model parameters

    Science.gov (United States)

    Lindner, Markus; Hopf, Barbara; Koch, Alexander W.; Roths, Johannes

    2017-04-01

    A 3D-FEM model has been developed to improve the understanding of multi-parameter sensing with Bragg gratings in attached or embedded polarization maintaining fibers. The material properties of the fiber, especially Young's modulus and Poisson's ratio of the fiber's stress applying parts, are crucial for accurate simulations, but are usually not provided by the manufacturers. A methodology is presented to determine the unknown parameters by using experimental characterizations of the fiber and iterative FEM simulations. The resulting 3D-Model is capable of describing the change in birefringence of the free fiber when exposed to longitudinal strain. In future studies the 3D-FEM model will be employed to study the interaction of PANDA fibers with the surrounding materials in which they are embedded.

  3. A Laplace method for under-determined Bayesian optimal experimental designs

    KAUST Repository

    Long, Quan

    2014-12-17

    In Long et al. (2013), a new method based on the Laplace approximation was developed to accelerate the estimation of the post-experimental expected information gains (Kullback–Leibler divergence) in model parameters and predictive quantities of interest in the Bayesian framework. A closed-form asymptotic approximation of the inner integral and the order of the corresponding dominant error term were obtained in the cases where the parameters are determined by the experiment. In this work, we extend that method to the general case where the model parameters cannot be determined completely by the data from the proposed experiments. We carry out the Laplace approximations in the directions orthogonal to the null space of the Jacobian matrix of the data model with respect to the parameters, so that the information gain can be reduced to an integration against the marginal density of the transformed parameters that are not determined by the experiments. Furthermore, the expected information gain can be approximated by an integration over the prior, where the integrand is a function of the posterior covariance matrix projected over the aforementioned orthogonal directions. To deal with the issue of dimensionality in a complex problem, we use either Monte Carlo sampling or sparse quadratures for the integration over the prior probability density function, depending on the regularity of the integrand function. We demonstrate the accuracy, efficiency and robustness of the proposed method via several nonlinear under-determined test cases. They include the designs of the scalar parameter in a one dimensional cubic polynomial function with two unidentifiable parameters forming a linear manifold, and the boundary source locations for impedance tomography in a square domain, where the unknown parameter is the conductivity, which is represented as a random field.

  4. SHORT COMMUNICATION GREEN CHEMISTRY VOLUMETRIC ...

    African Journals Online (AJOL)

    Preferred Customer

    INTRODUCTION. Titration is indispensable part of pharmaceutical chemistry, cosmetics, drug formulations, soaps, detergents and food engineering for estimation of acidity or basicity of the products. In chemistry, the titration is basic step of learning the chemical sciences. Usual titration apparatus require many experimental ...

  5. Experimental Determination and Modeling of the Phase Behavior for the Selective Oxidation of Benzyl Alcohol in Supercritical CO2

    DEFF Research Database (Denmark)

    Tsivintzelis, Ioannis; Beier, Matthias Josef; Grunwaldt, Jan-Dierk

    2011-01-01

    –benzaldehyde–water ternary mixtures were experimentally determined. The cubic plus association (CPA) equation of state was used to model the phase behavior of the experimentally investigated systems as well as the phase behavior of relevant mixtures that can exist inside the reactor during the reaction time...

  6. Force Field Benchmark of the TraPPE_UA for Polar Liquids: Density, Heat of Vaporization, Dielectric Constant, Surface Tension, Volumetric Expansion Coefficient, and Isothermal Compressibility.

    Science.gov (United States)

    Núñez-Rojas, Edgar; Aguilar-Pineda, Jorge Alberto; Pérez de la Luz, Alexander; de Jesús González, Edith Nadir; Alejandre, José

    2018-02-08

    The transferable potential for a phase equilibria force field in its united-atom version, TraPPE_UA, is evaluated for 41 polar liquids that include alcohols, thiols, ethers, sulfides, aldehydes, ketones, and esters to determine its ability to reproduce experimental properties that were not included in the parametrization procedure. The intermolecular force field parameters for pure components were fit to reproduce experimental boiling temperature, vapor-liquid coexisting densities, and critical point (temperature, density, and pressure) using Monte Carlo simulations in different ensembles. The properties calculated in this work are liquid density, heat of vaporization, dielectric constant, surface tension, volumetric expansion coefficient, and isothermal compressibility. Molecular dynamics simulations were performed in the gas and liquid phases, and also at the liquid-vapor interface. We found that relative error between calculated and experimental data is 1.2% for density, 6% for heat of vaporization, and 6.2% for surface tension, in good agreement with the experimental data. The dielectric constant is systematically underestimated, and the relative error is 37%. Evaluating the performance of the force field to reproduce the volumetric expansion coefficient and isothermal compressibility requires more experimental data.

  7. Experimentally induced states of mind determine abstinent smokers' level of craving in reaction to smoking-cues

    Directory of Open Access Journals (Sweden)

    Arie Dijkstra

    2015-06-01

    Conclusions: The present studies provide experimental evidence that levels of craving can be determined by momentary states of mind. This theoretical perspective can be integrated in existing conditioning and social cognitive learning perspectives on craving and substance use.

  8. Experimental determination about thermal comfort conditions in buildings; Determinacion experimental de las condiciones de confort termico en edificaciones

    Energy Technology Data Exchange (ETDEWEB)

    Ambriz Garcia, Juan Jose; Garcia Chavez, Jose Roberto; Paredes Rubio, Hernando Romero [Universidad Autonoma Metropolitana (Mexico)]. E-mail: agj@xanum.uam.mx; jgc@correo.azc.uam.mx; hrp@xanum.uam.mx

    2006-04-15

    This paper analyzes the thermal comfort importance in a building. And the influence it exerts on quality of life as well as the efficiency of people work activities. There are comments about some models which better help to estimate the recommended temperature levels. The experimental evaluation results from a Mexico City population sampler are presented. This work was done in a Controlled Environment Laboratory; the obtained outcomes proved the preferences occupants exceed the comfort zone greatest limit accepted in the reference international standards. The meaning of this conclusion is thermal comfort can be reached with higher temperatures and consequently an energy consumption and an environment impact decrease. [Spanish] En este trabajo se analiza la importancia que tiene el confort termico en la calidad de vida de las personas que ocupan una edificacion y en la eficiencia de sus actividades. Se comentan algunos modelos con los cuales se estiman los niveles de temperatura recomendados y se presentan los resultados de una evaluacion experimental realizada en un Laboratorio de Ambiente Controlado con una muestra de la poblacion del Distrito Federal. Los resultados que se obtuvieron demuestran que los ocupantes tienen preferencias que rebasan el limite superior de la zona de confort comunmente aceptada en los estandares internacionales de referencia. Esto quiere decir que el confort puede lograrse con mayores temperaturas, lo que se traduce en menor consumo de energia y menor impacto en el ambiente.

  9. BI-RADS Density Classification From Areometric and Volumetric Automatic Breast Density Measurements.

    Science.gov (United States)

    Østerås, Bjørn Helge; Martinsen, Anne Catrine T; Brandal, Siri Helene B; Chaudhry, Khalida Nasreen; Eben, Ellen; Haakenaasen, Unni; Falk, Ragnhild Sørum; Skaane, Per

    2016-04-01

    The aim of our study was to classify breast density using areometric and volumetric automatic measurements to best match Breast Imaging-Reporting and Data System (BI-RADS) density scores, and determine which technique best agrees with BI-RADS. Second, this study aimed to provide a set of threshold values for areometric and volumetric density to estimate BI-RADS categories. We randomly selected 537 full-field digital mammography examinations from a population-based screening program. Five radiologists assessed breast density using BI-RADS with all views available. A commercial program calculated areometric and volumetric breast density automatically. We compared automatically calculated density to all BI-RADS density thresholds using area under the receiver operating characteristic curve, and used Youden's index to estimate thresholds in automatic densities, with matching sensitivity and specificity. The 95% confidence intervals were estimated by bootstrapping. Areometric density correlated well with volumetric density (r(2) = 0.76, excluding outliers, n = 2). For the BI-RADS threshold between II and III, areometric and volumetric assessment showed about equal area under the curve (0.94 vs. 0.93). For the threshold between I and II, areometric assessment was better than volumetric assessment (0.91 vs. 0.86). For the threshold between III and IV, volumetric assessment was better than areometric assessment (0.97 vs. 0.92). Volumetric assessment is equal to or better than areometric assessment for the most clinically relevant thresholds (ie, between scattered fibroglandular and heterogeneously dense, and between heterogeneously dense and extremely dense breasts). Thresholds found in this study can be applied in daily practice to automatic measurements of density to estimate BI-RADS classification. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  10. Experimental determination of viability loss of Penicillium bilaiae conidia during convective air-drying.

    Science.gov (United States)

    Friesen, Timothy; Hill, Gordon; Pugsley, Todd; Holloway, Greg; Zimmerman, Deanna

    2005-08-01

    A study was conducted on the drying of Penicillium bilaiae, a fungal micro-organism used to promote soil-bound phosphorous uptake in several crop species, such as wheat, canola and pulse crops. A wet pellet formed from a mixture of the inoculant and a starch-based carrier was air-dried to the appropriate water activity to extend the shelf-life of the viable fungal conidia. Convective air-drying was examined as a low-energy alternative to the more expensive freeze-drying technology that is currently in use. Experiments were conducted to measure the loss of conidia viability during drying in a fixed-bed, thin-layer convective dryer. The dryer air inlet temperature and relative humidity were controlled in experiments to determine the effect of thermal and dessicative stresses on conidial viability. The measured survivor fraction was determined to be dependent on solids temperature, moisture content and drying rate. Thermal stresses became significant for process temperatures above 30 degrees C, while the survivor fraction fell sharply below a dry basis moisture ratio of 30%. Slower drying kinetics associated with high inlet air relative humidity were found to significantly improve the recovery of viable conidia. By minimising environmental stresses, survivor fractions of up to 75% could be achieved, but this result fell dramatically with the introduction of more severe conditions. A general linear statistical model is used to quantify experimental error and the significance level of each factor.

  11. Genetic determination of high productivity in experimental hybrid combinations of sugar beet (Beta vulgaris L.

    Directory of Open Access Journals (Sweden)

    М. О. Корнєєва

    2016-05-01

    Full Text Available Purpose. Creation of experimental sugar beet hybrid combinations of high sugar yield values and defining gene­tic determination of their heterotic effect. Methods. Diallel crossing and topcrossing, genetic analysis of quantitative traits. Results. The authors have studied the frequency of occurrence of sugar beet heterotic hybrid combinations for «sugar yield» trait created on the basis of two pollinator lines to be genetically valuable for productivity elements, CMS lines and single-cross sterile hybrids with the use of diallel and topcrossing system of controlled hybridization. The share of parental components’ effect and their interaction in CMS hybrids variability for productivity was determined. Expediency of heterotic forecasting based on high combining ability lines was substabtiated. Promising high-yielding sugar beet combinations were selected that exceeded the group standard by 4.1–16.3%. Conclusions. The theory of genetic balance by M. V. Turbin was confirmed. Such hybrids as [CMS 5OT 4]MGP 1 (116.3%, [CMS 1OT 2]MGP 1 (112.5% and [CMS 3OT 5]MGP 1 (113.2% were recognized as the best for their productivity, MGP 1 and MGP 2 lines – as the best for their combining ability.

  12. Experimental determination of one- and two-neutron separation energies for neutron-rich copper isotopes

    Science.gov (United States)

    Yu, Mian; Wei, Hui-Ling; Song, Yi-Dan; Ma, Chun-Wang

    2017-09-01

    A method is proposed to determine the one-neutron S n or two-neutron S 2n separation energy of neutron-rich isotopes. Relationships between S n (S 2n) and isotopic cross sections have been deduced from an empirical formula, i.e., the cross section of an isotope exponentially depends on the average binding energy per nucleon B/A. The proposed relationships have been verified using the neutron-rich copper isotopes measured in the 64A MeV 86Kr + 9Be reaction. S n, S 2n, and B/A for the very neutron-rich 77,78,79Cu isotopes are determined from the proposed correlations. It is also proposed that the correlations between S n, S 2n and isotopic cross sections can be used to find the location of neutron drip line isotopes. Supported by Program for Science and Technology Innovation Talents at Universities of Henan Province (13HASTIT046), Natural and Science Foundation in Henan Province (162300410179), Program for the Excellent Youth at Henan Normal University (154100510007) and Y-D Song thanks the support from the Creative Experimental Project of National Undergraduate Students (CEPNU 201510476017)

  13. Migration of oligomers from PET: determination of diffusion coefficients and comparison of experimental versus modelled migration.

    Science.gov (United States)

    Hoppe, Maria; Fornari, Roberta; de Voogt, Pim; Franz, Roland

    2017-07-01

    Polyethylene terephthalate (PET) is increasingly used as food-contact material in, for example, containers for beverage such as bottles for soft drinks, mineral water, juices and beer. Mass transport of substances present in packaging materials into the packed food and beverages is monitored to verify the food law compliance of the materials. PET is known to contain or give rise to migrants that are oligomers derived from the polymeric material. Until now their actual migration potential has been investigated only poorly. A convenient way to determine their migration would be by using models. To verify existing models with experimental data, a migration kinetic study of PET oligomers was conducted. PET bottle material was submerged in 50% ethanol at 80°C for 15 h. The oligomer content in the migration solutions was determined every hour using LC-MS with the first-series cyclic PET trimer as standard. Diffusion coefficients of five PET oligomers (first-series dimer and trimer, second-series dimer and trimer, and third-series dimer) were calculated from the obtained data and compared with the calculated diffusion coefficients using the models of Welle and Piringer. This is the first study to provide diffusion characteristics of oligomers in PET other than the first-series cyclic trimer.

  14. Computational tools for experimental determination and theoretical prediction of protein structure

    Energy Technology Data Exchange (ETDEWEB)

    O`Donoghue, S.; Rost, B.

    1995-12-31

    This tutorial was one of eight tutorials selected to be presented at the Third International Conference on Intelligent Systems for Molecular Biology which was held in the United Kingdom from July 16 to 19, 1995. The authors intend to review the state of the art in the experimental determination of protein 3D structure (focus on nuclear magnetic resonance), and in the theoretical prediction of protein function and of protein structure in 1D, 2D and 3D from sequence. All the atomic resolution structures determined so far have been derived from either X-ray crystallography (the majority so far) or Nuclear Magnetic Resonance (NMR) Spectroscopy (becoming increasingly more important). The authors briefly describe the physical methods behind both of these techniques; the major computational methods involved will be covered in some detail. They highlight parallels and differences between the methods, and also the current limitations. Special emphasis will be given to techniques which have application to ab initio structure prediction. Large scale sequencing techniques increase the gap between the number of known proteins sequences and that of known protein structures. They describe the scope and principles of methods that contribute successfully to closing that gap. Emphasis will be given on the specification of adequate testing procedures to validate such methods.

  15. Models of Determining the Parameters of Rock Mass Oscillation Equation with Experimental and Mass Blastings

    Directory of Open Access Journals (Sweden)

    Suzana Lutovac

    2018-02-01

    Full Text Available The explosion caused by detonation of explosive materials is followed by release of a large amount of energy. Whereby, a greater part of energy is used for rock destruction, and part of energy, in the form of seismic wave, is lost in the rock mass causing rock mass oscillation. Investigations of the character and behavior of the pattern of seismic wave indicate that the intensity and nature of the seismic wave are influenced by rock mass properties, and by blasting conditions. For evaluation and control of the seismic effect of blasting operations, the most commonly used equation is that of M.A. Sadovskii. Sadovskii’s equation defines the alteration in the velocity of rock mass oscillation depending on the distance, the quantity of explosives, blasting conditions and geological characteristics of the rock mass, and it is determined based on trial blasting for a specific work environment. Thus, this paper offers analysis of the method for determination of parameters of the rock mass oscillation equation, which are conditioned by rock mass properties and blasting conditions. Practical part of this paper includes the experimental research carried out at Majdanpek open pit, located in the northern part of eastern Serbia and the investigations carried out during mass blasting at Nepričava open pit, located in central Serbia. In this paper, parameters n and K from Sadovskii’s equation were determined in three ways—models in the given work environment. It was noted that, in practice, all three models can be successfully used to calculate the oscillation velocity of the rock masses.

  16. Experimental design of membrane sensor for selective determination of phenazopyridine hydrochloride based on computational calculations

    Energy Technology Data Exchange (ETDEWEB)

    Attia, Khalid A.M.; El-Abasawi, Nasr M.; Abdel-Azim, Ahmed H., E-mail: Ahmed.hussienabdelazim@hotmil.com

    2016-04-01

    Computational study has been done electronically and geometrically to select the most suitable ionophore to design a novel sensitive and selective electrochemical sensor for phenazopyridine hydrochloride (PAP). This study has revealed that sodium tetraphenylbarate (NaTPB) fits better with PAP than potassium tetrakis (KTClPB). The sensor design is based on the ion pair of PAP with NaTPB using dioctyl phthalate as a plasticizer. Under optimum conditions, the proposed sensor shows the slope of 59.5 mV per concentration decade in the concentration range of 1.0 × 10{sup −2}–1.0 × 10{sup −5} M with detection limit 8.5 × 10{sup −6} M. The sensor exhibits a very good selectivity for PAP with respect to a large number of interfering species as inorganic cations and sugars. The sensor enables track of determining PAP in the presence of its oxidative degradation product 2, 3, 6-Triaminopyridine, which is also its toxic metabolite. The proposed sensor has been successfully applied for the selective determination of PAP in pharmaceutical formulation. Also, the obtained results have been statistically compared to a reported electrochemical method indicating no significant difference between the investigated method and the reported one with respect to accuracy and precision. - Highlights: • Novel use of ISE for selective determination of phenazopyridine hydrochloride. • Investigating the degradation pathway of phenazopyridine with enough confirmation scan. • To avoid time-consuming and experimental trials, computational studies have been applied. • The proposed sensor shows high selectivity, reasonable detection limit and fast response.

  17. Experimental design of membrane sensor for selective determination of phenazopyridine hydrochloride based on computational calculations

    International Nuclear Information System (INIS)

    Attia, Khalid A.M.; El-Abasawi, Nasr M.; Abdel-Azim, Ahmed H.

    2016-01-01

    Computational study has been done electronically and geometrically to select the most suitable ionophore to design a novel sensitive and selective electrochemical sensor for phenazopyridine hydrochloride (PAP). This study has revealed that sodium tetraphenylbarate (NaTPB) fits better with PAP than potassium tetrakis (KTClPB). The sensor design is based on the ion pair of PAP with NaTPB using dioctyl phthalate as a plasticizer. Under optimum conditions, the proposed sensor shows the slope of 59.5 mV per concentration decade in the concentration range of 1.0 × 10 −2 –1.0 × 10 −5 M with detection limit 8.5 × 10 −6 M. The sensor exhibits a very good selectivity for PAP with respect to a large number of interfering species as inorganic cations and sugars. The sensor enables track of determining PAP in the presence of its oxidative degradation product 2, 3, 6-Triaminopyridine, which is also its toxic metabolite. The proposed sensor has been successfully applied for the selective determination of PAP in pharmaceutical formulation. Also, the obtained results have been statistically compared to a reported electrochemical method indicating no significant difference between the investigated method and the reported one with respect to accuracy and precision. - Highlights: • Novel use of ISE for selective determination of phenazopyridine hydrochloride. • Investigating the degradation pathway of phenazopyridine with enough confirmation scan. • To avoid time-consuming and experimental trials, computational studies have been applied. • The proposed sensor shows high selectivity, reasonable detection limit and fast response.

  18. Determination of equivalent breast phantoms for different age groups of Taiwanese women: An experimental approach

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Shang-Lung; Chu, Tieh-Chi; Lin, Yung-Chien; Lan, Gong-Yau; Yeh, Yu-Hsiu; Chen, Sharon; Chuang, Keh-Shih [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China); Department of Radiology, Cheng Hsin General Hospital, 45 Cheng Hsin Street, Pai-Tou District, Taipei 11220, Taiwan (China); Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 80708, Taiwan (China); Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan (China)

    2011-07-15

    Purpose: Polymethylmethacrylate (PMMA) slab is one of the mostly used phantoms for studying breast dosimetry in mammography. The purpose of this study was to evaluate the equivalence between exposure factors acquired from PMMA slabs and patient cases of different age groups of Taiwanese women in mammography. Methods: This study included 3910 craniocaudal screen/film mammograms on Taiwanese women acquired on one mammographic unit. The tube loading, compressed breast thickness (CBT), compression force, tube voltage, and target/filter combination for each mammogram were collected for all patients. The glandularity and the equivalent thickness of PMMA were determined for each breast using the exposure factors of the breast in combination with experimental measurements from breast-tissue-equivalent attenuation slabs. Equivalent thicknesses of PMMA to the breasts of Taiwanese women were then estimated. Results: The average {+-} standard deviation CBT and breast glandularity in this study were 4.2 {+-} 1.0 cm and 54% {+-} 23%, respectively. The average equivalent PMMA thickness was 4.0 {+-} 0.7 cm. PMMA slabs producing equivalent exposure factors as in the breasts of Taiwanese women were determined for the age groups 30-49 yr and 50-69 yr. For the 4-cm PMMA slab, the CBT and glandularity values of the equivalent breast were 4.1 cm and 65%, respectively, for the age group 30-49 yr and 4.4 cm and 44%, respectively, for the age group 50-69 yr. Conclusions: The average thickness of PMMA slabs producing the same exposure factors as observed in a large group of Taiwanese women is less than that reported for American women. The results from this study can provide useful information for determining a suitable thickness of PMMA for mammographic dose survey in Taiwan. The equivalence of PMMA slabs and the breasts of Taiwanese women is provided to allow average glandular dose assessment in clinical practice.

  19. Determination of equivalent breast phantoms for different age groups of Taiwanese women: An experimental approach

    International Nuclear Information System (INIS)

    Dong, Shang-Lung; Chu, Tieh-Chi; Lin, Yung-Chien; Lan, Gong-Yau; Yeh, Yu-Hsiu; Chen, Sharon; Chuang, Keh-Shih

    2011-01-01

    Purpose: Polymethylmethacrylate (PMMA) slab is one of the mostly used phantoms for studying breast dosimetry in mammography. The purpose of this study was to evaluate the equivalence between exposure factors acquired from PMMA slabs and patient cases of different age groups of Taiwanese women in mammography. Methods: This study included 3910 craniocaudal screen/film mammograms on Taiwanese women acquired on one mammographic unit. The tube loading, compressed breast thickness (CBT), compression force, tube voltage, and target/filter combination for each mammogram were collected for all patients. The glandularity and the equivalent thickness of PMMA were determined for each breast using the exposure factors of the breast in combination with experimental measurements from breast-tissue-equivalent attenuation slabs. Equivalent thicknesses of PMMA to the breasts of Taiwanese women were then estimated. Results: The average ± standard deviation CBT and breast glandularity in this study were 4.2 ± 1.0 cm and 54% ± 23%, respectively. The average equivalent PMMA thickness was 4.0 ± 0.7 cm. PMMA slabs producing equivalent exposure factors as in the breasts of Taiwanese women were determined for the age groups 30-49 yr and 50-69 yr. For the 4-cm PMMA slab, the CBT and glandularity values of the equivalent breast were 4.1 cm and 65%, respectively, for the age group 30-49 yr and 4.4 cm and 44%, respectively, for the age group 50-69 yr. Conclusions: The average thickness of PMMA slabs producing the same exposure factors as observed in a large group of Taiwanese women is less than that reported for American women. The results from this study can provide useful information for determining a suitable thickness of PMMA for mammographic dose survey in Taiwan. The equivalence of PMMA slabs and the breasts of Taiwanese women is provided to allow average glandular dose assessment in clinical practice.

  20. The criticality of sieve size in asphaltic concrete mixes as measured by volumetric properties and stabilities.

    Science.gov (United States)

    1971-01-01

    The purpose of this study was to investigate the effects of deviations from the specified aggregate gradation on the stability and volumetric properties of the S-5 mix. The project involved two phases of experimental work. The first phase consisted o...

  1. Volumetric 3-D Vector Flow Measurements using a 62+62 Row-Column Addressed Array

    DEFF Research Database (Denmark)

    Holbek, Simon; Stuart, Matthias Bo; Jensen, Jørgen Arendt

    2017-01-01

    Experimental results from volumetric 3-D vector flow measurements using a 62+62 row-column addressed (RCA) array are presented. A plane-by-plane steered transmit sequence and its post processing steps are described for obtaining 3-D vector flow in a volume. A modified version of the transverse...

  2. Hierarchical anatomical brain networks for MCI prediction: revisiting volumetric measures.

    Directory of Open Access Journals (Sweden)

    Luping Zhou

    Full Text Available Owning to its clinical accessibility, T1-weighted MRI (Magnetic Resonance Imaging has been extensively studied in the past decades for prediction of Alzheimer's disease (AD and mild cognitive impairment (MCI. The volumes of gray matter (GM, white matter (WM and cerebrospinal fluid (CSF are the most commonly used measurements, resulting in many successful applications. It has been widely observed that disease-induced structural changes may not occur at isolated spots, but in several inter-related regions. Therefore, for better characterization of brain pathology, we propose in this paper a means to extract inter-regional correlation based features from local volumetric measurements. Specifically, our approach involves constructing an anatomical brain network for each subject, with each node representing a Region of Interest (ROI and each edge representing Pearson correlation of tissue volumetric measurements between ROI pairs. As second order volumetric measurements, network features are more descriptive but also more sensitive to noise. To overcome this limitation, a hierarchy of ROIs is used to suppress noise at different scales. Pairwise interactions are considered not only for ROIs with the same scale in the same layer of the hierarchy, but also for ROIs across different scales in different layers. To address the high dimensionality problem resulting from the large number of network features, a supervised dimensionality reduction method is further employed to embed a selected subset of features into a low dimensional feature space, while at the same time preserving discriminative information. We demonstrate with experimental results the efficacy of this embedding strategy in comparison with some other commonly used approaches. In addition, although the proposed method can be easily generalized to incorporate other metrics of regional similarities, the benefits of using Pearson correlation in our application are reinforced by the experimental

  3. Experimental Determination of in Situ Utilization of Lunar Regolith for Thermal Energy Storage

    Science.gov (United States)

    Richter, Scott W.

    1993-01-01

    A Lunar Thermal Energy from Regolith (LUTHER) experiment has been designed and fabricated at the NASA Lewis Research Center to determine the feasibility of using lunar soil as thermal energy storage media. The experimental apparatus includes an alumina ceramic canister (25.4 cm diameter by 45.7 cm length) which contains simulated lunar regolith, a heater (either radiative or conductive), 9 heat shields, a heat transfer cold jacket, and 19 type B platinum rhodium thermocouples. The simulated lunar regolith is a basalt, mined and processed by the University of Minnesota, that closely resembles the lunar basalt returned to earth by the Apollo missions. The experiment will test the effects of vacuum, particle size, and density on the thermophysical properties of the regolith. The properties include melt temperature (range), specific heat, thermal conductivity, and latent heat of storage. Two separate tests, using two different heaters, will be performed to study the effect of heating the system using radiative and conductive heat transfer. The physical characteristics of the melt pattern, material compatibility of the molten regolith, and the volatile gas emission will be investigated by heating a portion of the lunar regolith to its melting temperature (1435 K) in a 10(exp -4) pascal vacuum chamber, equipped with a gas spectrum analyzer. A finite differencing SINDA model was developed at NASA Lewis Research Center to predict the performance of the LUTHER experiment. The analytical results of the code will be compared with the experimental data generated by the LUTHER experiment. The code will predict the effects of vacuum, particle size, and density has on the heat transfer to the simulated regolith.

  4. Determination of Experimental Fuel Rod Parameters using 3D Modelling of PCMI with MPS Defect

    Energy Technology Data Exchange (ETDEWEB)

    Casagranda, Albert [Idaho National Laboratory; Spencer, Benjamin Whiting [Idaho National Laboratory; Pastore, Giovanni [Idaho National Laboratory; Novascone, Stephen Rhead [Idaho National Laboratory; Hales, Jason Dean [Idaho National Laboratory; Williamson, Richard L [Idaho National Laboratory; Martineau, Richard Charles [Idaho National Laboratory

    2016-05-01

    An in-reactor experiment is being designed in order to validate the pellet-cladding mechanical interaction (PCMI) behavior of the BISON fuel performance code. The experimental parameters for the test rod being placed in the Halden Research Reactor are being determined using BISON simulations. The 3D model includes a missing pellet surface (MPS) defect to generate large local cladding deformations, which should be measureable after typical burnup times. The BISON fuel performance code is being developed at Idaho National Laboratory (INL) and is built on the Multiphysics Object-Oriented Simulation Environment (MOOSE) framework. BISON supports both 2D and 3D finite elements and solves the fully coupled equations for solid mechanics, heat conduction and species diffusion. A number of fuel performance effects are included using models for swelling, densification, creep, relocation and fission gas production & release. In addition, the mechanical and thermal contact between the fuel and cladding is explicitly modelled using a master-slave based contact algorithm. In order to accurately predict PCMI effects, the BISON code includes the relevant physics involved and provides a scalable and robust solution procedure. The depth of the proposed MPS defect is being varied in the BISON model to establish an optimum value for the experiment. The experiment will be interrupted approximately every 6 months to measure cladding radial deformation and provide data to validate BISON. The complete rodlet (~20 discrete pellets) is being simulated using a 180° half symmetry 3D model with MPS defects at two axial locations. In addition, annular pellets will be used at the top and bottom of the pellet stack to allow thermocouples within the rod to measure the fuel centerline temperature. Simulation results will be presented to illustrate the expected PCMI behavior and support the chosen experimental design parameters.

  5. Experimental infection of T4 Acanthamoeba genotype determines the pathogenic potential.

    Science.gov (United States)

    Alves, Daniella de Sousa Mendes Moreira; Moraes, Aline Silva; Alves, Luciano Moreira; Gurgel-Gonçalves, Rodrigo; Lino Junior, Ruy de Souza; Cuba-Cuba, César Augusto; Vinaud, Marina Clare

    2016-09-01

    T4 is the Acanthamoeba genotype most related to cases of granulomatous amoebic encephalitis (GAE) in immunocompromised patients and of keratitis in contact lens wearers. The determination of the pathogenic potential of Acanthamoeba clinical and environmental isolates using experimental models is extremely important to elucidate the capacity of free-living organisms to establish and cause disease in hosts. The aim of this study was to compare and evaluate the histopathology and culture between two different routes of experimental infection of T4 Acanthamoeba isolated from environmental and clinical source in mice (intracranial and intraperitoneal). Swiss isogenic healthy mice were inoculated with 10(4) trophozoites by intracranial (IC) and intraperitoneal (IP) routes and observed during 21 days. The brains from animals inoculated by the IC route were collected and from the animals of the IP inoculation group, the brains, livers, kidneys, spleens, and lungs were removed. The organs were prepared and appropriately divided to be evaluated with histopathology and culture. There was no significant difference between the inoculation routes in terms of isolates recovery (χ(2) = 0.09; p = 0.76). In the IC group, isolate recovery rate was significantly higher in histopathology than the one achieved by culture (χ(2) = 6.45; p Acanthamoeba in both routes. This work represents the first in vivo pathogenicity assay of primary isolation source in Central region of Brazil showing in vivo pathogenicity and hematogenous spread capacity of these protozoa, improving the knowledge on free-living amoebae isolates.

  6. Green chemistry volumetric titration kit for pharmaceutical ...

    African Journals Online (AJOL)

    Stopcock SC and Spring Sp models of Econoburette (Calibrated, RTC (NR), Ministry of Small Scale Industries, Government of India), developed for semimicro volumetric titration of pharmaceutical formulations are reported. These are economized and risk free titration where pipette is replaced by an inbuilt pipette and ...

  7. Volumetric, dashboard-mounted augmented display

    Science.gov (United States)

    Kessler, David; Grabowski, Christopher

    2017-11-01

    The optical design of a compact volumetric display for drivers is presented. The system displays a true volume image with realistic physical depth cues, such as focal accommodation, parallax and convergence. A large eyebox is achieved with a pupil expander. The windshield is used as the augmented reality combiner. A freeform windshield corrector is placed at the dashboard.

  8. Theoretical and experimental determination of dosimetric characteristics for ADVANTAGETM Pd-103 brachytherapy source

    International Nuclear Information System (INIS)

    Meigooni, Ali S.; Dini, Sharifeh A.; Awan, Shahid B.; Dou, Kai; Koona, Rafiq A.

    2006-01-01

    ADVANTAGE TM Pd-103 brachytherapy source has been recently introduced by IsoAid TM for prostate permanent implants. Dosimetric characteristics (Dose rate constant, radial dose function, 2D-, and 1D-anisotropy functions) of this source model have been determined using both theoretical and experimental methods, following the updated TG-43U1 protocol. Derivation of the dose rate constant was based on recent NIST WAFAC calibration performed in accordance with the 1999 Standards. Measurements were performed in Solid Water TM using LiF TLD chips and the theoretical calculations were performed in Solid Water TM and liquid water phantom materials using PTRAN Monte Carlo code. The results of the Monte Carlo simulation have shown a dose rate constant of 0.69 cGy h -1 U -1 in liquid water and 0.67 cGy h -1 U -1 in Solid Water TM medium. The measured dose rate constant in Solid Water TM was found to be 0.68±8% cGy h -1 U -1 , which is in a good agreement (within ±5%) to the Monte Carlo simulated data. The 2D- and 1D-anisotropy functions of the ADVANTAGE TM Pd-103 source were calculated for radial distances ranging from 0.5 to 5.0 cm. Radial dose function was determined for radial distances ranging from 0.2 to 8.0 cm using line source approximation. All these calculations are based on L eff equal to 3.61 cm, calculated following TG-43U1 recommendations. The tabulated data for 2D-anisotropy function, 1D-anisotropy function, dose rate constant and radial dose function have been produced for clinical application of this source model

  9. Determination of BTEX in surface and ground waters at Centro Experimental Aramar area

    International Nuclear Information System (INIS)

    Matoso, Erika; Oliveira, Rando M. de; Segre, Nádia

    2017-01-01

    The mixture of the monocyclic aromatic compounds benzene, toluene, ethylbenzene and xylene isomers is defined as BTEX. The presence of BTEX in the environment is regularly associated with petroleum and its byproducts leakages or industrial effluent discharge. BTEX may cause serious problems to human and animal health. Human exposure to these aromatic compounds can lead to eye and skin irritation, central nervous system weakening and bone marrow depression. According to World Health Organization (WHO) benzene can cause cancer development. A new unit process in Centro Experimental Aramar (CEA) using BTEX-containing products will be launched shortly. Therefore, BTEX monitoring will be necessary since effluents release in Brazil is controlled by CONAMA regulations. Besides, as these compounds has never been evaluated in CEA, it is important to provide knowledge on the current BTEX concentration, in order to establish pre-operational values in CEA region and nearby. The CONAMA regulations for BTEX in superficial waters sets very low limits (such as 0,002 mg L- 1 for toluene and 0,005 mg L-1 for benzene). For this reason, it was developed in this work an analytical method by Headspace-GC-MS to achieve these values. The figures of merit determined were limit of detection (LOD), limit of quantification (LOQ), precision and accuracy. BTEX was analyzed in superficial waters from three different sampling points at Ipanema River and ground water collected in eight different sampling points. All sampling points were located a ratio 10 km radius from CEA. (author)

  10. Prediction and experimental determination of the solubility of exotic scales at high temperatures - Zinc sulfide

    DEFF Research Database (Denmark)

    Carolina Figueroa Murcia, Diana; Fosbøl, Philip Loldrup; Thomsen, Kaj

    2016-01-01

    The presence of "exotic" scale such as Zinc Sulfide (ZnS), Lead Sulfide (PbS) and Iron Sulfide (FeS) in HP/HT reservoirs has been identified. "Exotic" scale materials come as a new challenge in HP/HT reservoirs. This has led to the development of more advanced tools to predict their behavior...... at extreme conditions. The aim of this work is to include ZnS into the group of scale materials that can be modeled with the Extended UNIQUAC model. Solubility data for ZnS are scarce in the open literature. In order to improve the available data, we study the experimental behavior of ZnS solubility at high...... temperatures. The determination of the solubility of ZnS is carried out at temperatures up to 250°C. Zinc sulfide (99.99%) and ultra-pure water are placed in a vial in a reduced oxygen atmosphere. The sample is placed in a controlled bath and stirred until equilibrium is attained. The suspension is filtered...

  11. Electrodialytic desalination of brackish water: determination of optimal experimental parameters using full factorial design

    Science.gov (United States)

    Gmar, Soumaya; Helali, Nawel; Boubakri, Ali; Sayadi, Ilhem Ben Salah; Tlili, Mohamed; Amor, Mohamed Ben

    2017-12-01

    The aim of this work is to study the desalination of brackish water by electrodialysis (ED). A two level-three factor (23) full factorial design methodology was used to investigate the influence of different physicochemical parameters on the demineralization rate (DR) and the specific power consumption (SPC). Statistical design determines factors which have the important effects on ED performance and studies all interactions between the considered parameters. Three significant factors were used including applied potential, salt concentration and flow rate. The experimental results and statistical analysis show that applied potential and salt concentration are the main effect for DR as well as for SPC. The effect of interaction between applied potential and salt concentration was observed for SPC. A maximum value of 82.24% was obtained for DR under optimum conditions and the best value of SPC obtained was 5.64 Wh L-1. Empirical regression models were also obtained and used to predict the DR and the SPC profiles with satisfactory results. The process was applied for the treatment of real brackish water using the optimal parameters.

  12. Determination of BTEX in surface and ground waters at Centro Experimental Aramar area

    Energy Technology Data Exchange (ETDEWEB)

    Matoso, Erika; Oliveira, Rando M. de; Segre, Nádia, E-mail: ematoso@hotmail.com [Centro Tecnológico da Marinha em São Paulo (CEA/CTMSP), Iperó, SP (Brazil). Centro Experimental Aramar

    2017-07-01

    The mixture of the monocyclic aromatic compounds benzene, toluene, ethylbenzene and xylene isomers is defined as BTEX. The presence of BTEX in the environment is regularly associated with petroleum and its byproducts leakages or industrial effluent discharge. BTEX may cause serious problems to human and animal health. Human exposure to these aromatic compounds can lead to eye and skin irritation, central nervous system weakening and bone marrow depression. According to World Health Organization (WHO) benzene can cause cancer development. A new unit process in Centro Experimental Aramar (CEA) using BTEX-containing products will be launched shortly. Therefore, BTEX monitoring will be necessary since effluents release in Brazil is controlled by CONAMA regulations. Besides, as these compounds has never been evaluated in CEA, it is important to provide knowledge on the current BTEX concentration, in order to establish pre-operational values in CEA region and nearby. The CONAMA regulations for BTEX in superficial waters sets very low limits (such as 0,002 mg L- 1 for toluene and 0,005 mg L-1 for benzene). For this reason, it was developed in this work an analytical method by Headspace-GC-MS to achieve these values. The figures of merit determined were limit of detection (LOD), limit of quantification (LOQ), precision and accuracy. BTEX was analyzed in superficial waters from three different sampling points at Ipanema River and ground water collected in eight different sampling points. All sampling points were located a ratio 10 km radius from CEA. (author)

  13. Experimentally determined subsolidus metal-olivine element partitioning with applications to pallasites

    Science.gov (United States)

    Donohue, Patrick H.; Hill, Eddy; Huss, Gary R.

    2018-02-01

    Pallasite meteorites, which consist primarily of olivine and metal, may be remnants of disrupted core-mantle boundaries of differentiated asteroids or planetesimals. The early thermal histories of pallasites are potentially recorded by minor- and trace-element zonation in olivine. However, constraining this history requires knowledge of element behavior under the conditions of pallasite formation, which is lacking for many of the main elements of interest (e.g., Co, Cr, Mn). In this study, we experimentally determined metal/olivine partition coefficients for Fe, Ni, Co, Cr, and Mn in a pallasite analogue at subsolidus temperatures. Metal/olivine partition coefficients (KM) increase in the order KMn rims varies significantly for the investigated transition metals. We suggest rim zonation results from partial re-equilibration during late stage crystallization of minor phases (e.g., chromite, phosphates). This re-equilibration occurred over short timescales relative to overall pallasite cooling, likely tied to initial cooling rates on the order of 100-300 °C/Myr.

  14. Cellular uptake of nanoparticles as determined by particle properties, experimental conditions, and cell type.

    Science.gov (United States)

    Kettler, Katja; Veltman, Karin; van de Meent, Dik; van Wezel, Annemarie; Hendriks, A Jan

    2014-03-01

    The increased application of nanoparticles (NPs) is increasing the risk of their release into the environment. Although many toxicity studies have been conducted, the environmental risk is difficult to estimate, because uptake mechanisms are often not determined in toxicity studies. In the present study, the authors review dominant uptake mechanisms of NPs in cells, as well as the effect of NP properties, experimental conditions, and cell type on NP uptake. Knowledge of NP uptake is crucial for risk assessment and is essential to predict the behavior of NPs based on their physical-chemical properties. Important uptake mechanisms for eukaryotic cells are macropinocytosis, receptor-mediated endocytosis, and phagocytosis in specialized mammalian cells. The studies reviewed demonstrate that uptake into nonphagocytic cells depends strongly on NP size, with an uptake optimum at an NP diameter of approximately 50 nm. Increasing surface charges, either positive or negative, have been shown to increase particle uptake in comparison with uncharged NPs. Another important factor is the degree of (homo-) aggregation. Results regarding shape have been ambiguous. Difficulties in the production of NPs, with 1 property changed at a time, call for a full characterization of NP properties. Only then will it be possible to draw conclusions as to which property affected the uptake. © 2013 SETAC.

  15. Experimental determination of chosen document elements parameters from raster graphics sources

    Directory of Open Access Journals (Sweden)

    Jiří Rybička

    2010-01-01

    Full Text Available Visual appearance of documents and their formal quality is considered to be as important as the content quality. Formal and typographical quality of documents can be evaluated by an automated system that processes raster images of documents. A document is described by a formal model that treats a page as an object and also as a set of elements, whereas page elements include text and graphic object. All elements are described by their parameters depending on elements’ type. For future evaluation, mainly text objects are important. This paper describes the experimental determination of chosen document elements parameters from raster images. Techniques for image processing are used, where an image is represented as a matrix of dots and parameter values are extracted. Algorithms for parameter extraction from raster images were designed and were aimed mainly at typographical parameters like indentation, alignment, font size or spacing. Algorithms were tested on a set of 100 images of paragraphs or pages and provide very good results. Extracted parameters can be directly used for typographical quality evaluation.

  16. Desorption modeling of hydrophobic organic chemicals from plastic sheets using experimentally determined diffusion coefficients in plastics.

    Science.gov (United States)

    Lee, Hwang; Byun, Da-Eun; Kim, Ju Min; Kwon, Jung-Hwan

    2018-01-01

    To evaluate rate of migration from plastic debris, desorption of model hydrophobic organic chemicals (HOCs) from polyethylene (PE)/polypropylene (PP) films to water was measured using PE/PP films homogeneously loaded with the HOCs. The HOCs fractions remaining in the PE/PP films were compared with those predicted using a model characterized by the mass transfer Biot number. The experimental data agreed with the model simulation, indicating that HOCs desorption from plastic particles can generally be described by the model. For hexachlorocyclohexanes with lower plastic-water partition coefficients, desorption was dominated by diffusion in the plastic film, whereas desorption of chlorinated benzenes with higher partition coefficients was determined by diffusion in the aqueous boundary layer. Evaluation of the fraction of HOCs remaining in plastic films with respect to film thickness and desorption time showed that the partition coefficient between plastic and water is the most important parameter influencing the desorption half-life. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Volumetric B1 (+) mapping of the brain at 7T using DREAM.

    Science.gov (United States)

    Nehrke, Kay; Versluis, Maarten J; Webb, Andrew; Börnert, Peter

    2014-01-01

    To tailor and optimize the Dual Refocusing Echo Acquisition Mode (DREAM) approach for volumetric B1 (+) mapping of the brain at 7T. A new DREAM echo timing scheme based on the virtual stimulated echo was derived to minimize potential effects of transverse relaxation. Furthermore, the DREAM B1 (+) mapping performance was investigated in simulations and experimentally in phantoms and volunteers for volumetric applications, studying and optimizing the accuracy of the sequence with respect to saturation effects, slice profile imperfections, and T1 and T2 relaxation. Volumetric brain protocols were compiled for different isotropic resolutions (5-2.5 mm) and SENSE factors, and were studied in vivo for different RF drive modes (circular/linear polarization) and the application of dielectric pads. Volumetric B1 (+) maps with good SNR at 2.5 mm isotropic resolution were acquired in about 20 s or less. The specific absorption rate was well below the safety limits for all scans. Mild flow artefacts were observed in the large vessels. Moreover, a slight contrast in the ventricle was observed in the B1 (+) maps, which could be attributed to T1 and T2 relaxation effects. DREAM enables safe, very fast, and robust volumetric B1 (+) mapping of the brain at ultrahigh fields. Copyright © 2013 Wiley Periodicals, Inc.

  18. Experimental determination of thermal conductivities of dielectric thin films; Determination experimentale des conductivites thermiques de couches minces dielectriques

    Energy Technology Data Exchange (ETDEWEB)

    Scudeller, Y.; Hmina, N.; Lahmar, J.; Bardon, J.P. [Nantes Univ., 44 (France)

    1996-12-31

    This paper presents a method of measurement of thermal conductivity of sub-micron dielectric films in a direction perpendicular to the substrate. These films (oxides, nitrides, diamond..) are mainly used for the electrical insulation of semiconductor circuits and in optical treatments of high energy lasers. The principle of the method used and the experimental device are described. The results obtained with silicon oxides are discussed. (J.S.) 13 refs.

  19. Experimental Determination and Thermodynamic Modeling of Electrical Conductivity of SRS Waste Tank Supernate

    Energy Technology Data Exchange (ETDEWEB)

    Pike, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Reboul, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-06-01

    SRS High Level Waste Tank Farm personnel rely on conductivity probes for detection of incipient overflow conditions in waste tanks. Minimal information is available concerning the sensitivity that must be achieved such that that liquid detection is assured. Overly sensitive electronics results in numerous nuisance alarms for these safety-related instruments. In order to determine the minimum sensitivity required of the probe, Tank Farm Engineering personnel need adequate conductivity data to improve the existing designs. Little or no measurements of liquid waste conductivity exist; however, the liquid phase of the waste consists of inorganic electrolytes for which the conductivity may be calculated. Savannah River Remediation (SRR) Tank Farm Facility Engineering requested SRNL to determine the conductivity of the supernate resident in SRS waste Tank 40 experimentally as well as computationally. In addition, SRNL was requested to develop a correlation, if possible, that would be generally applicable to liquid waste resident in SRS waste tanks. A waste sample from Tank 40 was analyzed for composition and electrical conductivity as shown in Table 4-6, Table 4-7, and Table 4-9. The conductivity for undiluted Tank 40 sample was 0.087 S/cm. The accuracy of OLI Analyzer™ was determined using available literature data. Overall, 95% of computed estimates of electrical conductivity are within ±15% of literature values for component concentrations from 0 to 15 M and temperatures from 0 to 125 °C. Though the computational results are generally in good agreement with the measured data, a small portion of literature data deviates as much as ±76%. A simplified model was created that can be used readily to estimate electrical conductivity of waste solution in computer spreadsheets. The variability of this simplified approach deviates up to 140% from measured values. Generally, this model can be applied to estimate the conductivity within a factor of two. The comparison of the

  20. Temperature and volumetric water content petrophysical relationships in municipal solid waste for the interpretation of bulk electrical resistivity data

    Science.gov (United States)

    Pilawski, Tamara; Dumont, Gaël; Nguyen, Frédéric

    2015-04-01

    Landfills pose major environmental issues including long-term methane emissions, and local pollution of soil and aquifers but can also be seen as potential energy resources and mining opportunities. Water content in landfills determine whether solid fractions can be separated and recycled, and controls the existence and efficiency of natural or enhanced biodegradation. Geophysical techniques, such as electrical and electromagnetic methods have proven successful in the detection and qualitative investigation of sanitary landfills. However, their interpretation in terms of quantitative water content estimates makes it more challenging due to the influence of parameters such as temperature, compaction, waste composition or pore fluid. To improve the confidence given to bulk electrical resistivity data and to their interpretation, we established temperature and volumetric water content petrophysical relationships that we tested on field and laboratory electrical resistivity measurements. We carried out two laboratory experiments on leachates and waste samples from a landfill located in Mont-Saint-Guibert, Belgium. We determined a first relationship between temperature and electrical resistivity with pure and diluted leachates by progressively increasing the temperature from 5°C to 65°C, and then cooling down to 5°C. The second relationship was obtained by measuring electrical resistivity on waste samples of different volumetric water contents. First, we used the correlations obtained from the experiments to compare electrical resistivity measurements performed in a landfill borehole and on reworked waste samples excavated at different depths. Electrical resistivities were measured every 20cm with an electromagnetic logging device (EM39) while a temperature profile was acquired with optic fibres. Waste samples were excavated every 2m in the same borehole. We filled experimental columns with these samples and measured electrical resistivities at laboratory temperature

  1. Experimental determination of aerosol deposition velocity on vegetation and on other sampling areas

    International Nuclear Information System (INIS)

    Jonas, R.; Vogt, K.J.

    1982-04-01

    The deposition velocity of aerosols with diameters between 0.4 and 17 μm, required for environmental exposure calculations, was experimentally determined in fifty-two field tests. The results of the deposition experiments on grass indicate that the deposition velocity is proportional to the friction velocity and depends on both the vegetation dry mass and on the aerosol diameter. The deposition velocity can be represented as an inverse polynominal function of the 3rd order as a function of the aerosol diameter. This demonstrated that the deposition velocity increases especially rapidly (by a factor of about 10) between diameters of 4 and 6 μm, for which turbulence deposition is characteristic, while the rise diminishes for larger particles, for which sedimentation is important. It can be assumed that in the normal operation of nuclear power stations and in the case of incidents in which radioactive substances are released in a filtered condition, a particle diameter of 3 μm is not exceeded and differences in friction velocity and dry mass are cancelled out in the temporal mean. At a mean friction velocity of 27 cm/s and a representative dry mass for grass of 0.017 g/cm 2 deposition velocities of 0.01, 0.02, 0.05, 0.42 and 4.6 cm/s resulted, corresponding to particle diameters of 1, 2, 3, 5 and 10 μm. This indicates that the reference value of 0.1 cm/s, given in the 'Allgemeine Berechnungsgrundlage' for the normal operation of nuclear power stations, is sufficiently conservative. The mean deposition velocity for clover was higher by a factor of approximately 2, for artificial interfaces (smooth and structured metals, filters) and soil by a factor of approximately 3 and thus 2 lower than for grass. (orig./HP)

  2. CCDC 713130: Experimental Crystal Structure Determination : bis(2,5-Dihydrobenzylammonium) hexachloro-osmium(iv)

    KAUST Repository

    Reiner, T.

    2011-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  3. CCDC 1515632: Experimental Crystal Structure Determination : hexakis(dimethyl sulfoxide)-manganese(ii) tetraiodide

    KAUST Repository

    Haque, M.A.

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  4. CCDC 844303: Experimental Crystal Structure Determination : 1,1,3,3-Tetraphenyldiphosphoxane 1,3-disulfide

    KAUST Repository

    Al-Masri, H.T.

    2012-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  5. CCDC 721713: Experimental Crystal Structure Determination : Dichloro-(ethyl phenylalaninate)-tris(pyridine)-ruthenium(ii)

    KAUST Repository

    Reiner, Thomas

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  6. CCDC 930139: Experimental Crystal Structure Determination : Chloro-(1-cyclododecyl-3-mesitylimidazol-2-ylidene)-silver

    KAUST Repository

    Queval, Pierre

    2014-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  7. CCDC 1419754: Experimental Crystal Structure Determination : octakis(mu2-2-phenylethanethiolato)-tetra-nickel

    KAUST Repository

    Joya, Khurram S.

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  8. CCDC 1419731: Experimental Crystal Structure Determination : dodecakis(mu-2-phenylethanethiolato)-hexa-nickel dichloromethane solvate

    KAUST Repository

    Joya, Khurram S.

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  9. CCDC 1477678: Experimental Crystal Structure Determination : (1,3-dimesitylimidazolidin-2-ylidene)-trimethyl-gallium

    KAUST Repository

    Wu, Melissa M.

    2017-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  10. CCDC 1477679: Experimental Crystal Structure Determination : (1,3-dimesitylimidazolidin-2-ylidene)-trimethyl-indium

    KAUST Repository

    Wu, Melissa M.

    2017-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  11. CCDC 1024814: Experimental Crystal Structure Determination : 1,3-Dimesitylimidazolidine-2-selenone

    KAUST Repository

    Vummaleti, Sai V. C.

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  12. CCDC 1015953: Experimental Crystal Structure Determination : 1,3,6,8-tetrakis(4-phenoxyphenyl)pyrene

    KAUST Repository

    El-Assaad, Tarek H.

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  13. CCDC 1011330: Experimental Crystal Structure Determination : 1,3,6,8-tetrakis(4-fluorophenyl)pyrene

    KAUST Repository

    El-Assaad, Tarek H.

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  14. CCDC 1436716: Experimental Crystal Structure Determination : 5-fluoro-4-iodo-2,1,3-benzothiadiazole

    KAUST Repository

    Shi, Qinqin

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  15. CCDC 1436717: Experimental Crystal Structure Determination : 2-bromo-4,5-diiodo-1,3-thiazole

    KAUST Repository

    Shi, Qinqin

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  16. CCDC 1010350: Experimental Crystal Structure Determination : dichloro-(methylenebis(di-t-butylphosphine))-palladium(ii)

    KAUST Repository

    Roesle, Philipp

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  17. CCDC 1446070: Experimental Crystal Structure Determination : tris(Pentafluorophenyl)-(triethylsilyl formate)-boron

    KAUST Repository

    Chen, Jiawei

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  18. CCDC 713129: Experimental Crystal Structure Determination : (eta^6^-Benzylammonium)-dichloro-(dimethylsulfoxide-S)-ruthenium(ii) chloride

    KAUST Repository

    Reiner, T.

    2011-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  19. CCDC 721712: Experimental Crystal Structure Determination : (N-(2-Aminoethyl)-4-methylbenzenesulfonamidato)-(phenylalaninato)-ruthenium dimethylsulfoxide solvate

    KAUST Repository

    Reiner, Thomas

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  20. CCDC 844302: Experimental Crystal Structure Determination : N-1-Naphthyl-P,P-diphenylphosphinoselenoic amide

    KAUST Repository

    Al-Masri, H.T.

    2012-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  1. CCDC 1475929: Experimental Crystal Structure Determination : trimethylammonium tribromo-tin(iv)

    KAUST Repository

    Dang, Yangyang

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  2. CCDC 1475931: Experimental Crystal Structure Determination : trimethylammonium trichloro-tin(iv)

    KAUST Repository

    Dang, Yangyang

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  3. CCDC 887968: Experimental Crystal Structure Determination : Dichloro-bis(tricyclohexylphosphine)-(3-phenylindenylidene)-ruthenium tetrahydrofuran solvate

    KAUST Repository

    Urbina-Blanco, C.A.

    2014-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  4. CCDC 933273: Experimental Crystal Structure Determination : Chloro-(1-cyclododecyl-3-mesitylimidazol-2-ylidene)-gold

    KAUST Repository

    Queval, Pierre

    2014-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  5. CCDC 1059905: Experimental Crystal Structure Determination : 7,13-dimesitylindeno[1,2-b]thioxanthene

    KAUST Repository

    Shi, Xueliang

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  6. CCDC 951636: Experimental Crystal Structure Determination : bis(tetra-n-butylammonium) trichloro-(nitrosyl)-(oxalato)-ruthenium

    KAUST Repository

    Kuhn, Paul-Steffen

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  7. CCDC 1427126: Experimental Crystal Structure Determination : bis(1,10-Phenanthroline)-copper pentafluoropropanoate

    KAUST Repository

    Huang, Yangjie

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  8. CCDC 1446069: Experimental Crystal Structure Determination : tris(Pentafluorophenyl)-(triethylsilyl formate)-aluminium

    KAUST Repository

    Chen, Jiawei

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  9. CCDC 1420582: Experimental Crystal Structure Determination : catena-[(mu-4,4'-sulfonyldibenzoato)-calcium ethane

    KAUST Repository

    Plonka, Anna M.

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  10. CCDC 1420581: Experimental Crystal Structure Determination : catena-[(mu-4,4'-sulfonyldibenzoato)-calcium ethylene

    KAUST Repository

    Plonka, Anna M.

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  11. CCDC 1429311: Experimental Crystal Structure Determination : N-(5-Bromoquinolin-8-yl)benzamide

    KAUST Repository

    Xu, Jun

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  12. CCDC 1482638: Experimental Crystal Structure Determination : trimethylammonium trichloro-tin(iv)

    KAUST Repository

    Dang, Yangyang

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  13. CCDC 1420580: Experimental Crystal Structure Determination : catena-[(mu-4,4'-sulfonyldibenzoato)-calcium acetylene

    KAUST Repository

    Plonka, Anna M.

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  14. CCDC 1475930: Experimental Crystal Structure Determination : trimethylammonium trichloro-tin(iv)

    KAUST Repository

    Dang, Yangyang

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  15. CCDC 1427127: Experimental Crystal Structure Determination : bis(1,10-Phenanthroline)-copper heptafluorobutanoate benzene solvate

    KAUST Repository

    Huang, Yangjie

    2016-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  16. CCDC 1048729: Experimental Crystal Structure Determination : bis(2-(hydroxyimino)-3-phenylpropanoato)-tin(ii)

    KAUST Repository

    Khanderi, Jayaprakash

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  17. CCDC 1048727: Experimental Crystal Structure Determination : bis(2-(hydroxyimino)propanoato)-tin(ii)

    KAUST Repository

    Khanderi, Jayaprakash

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  18. CCDC 1048728: Experimental Crystal Structure Determination : ammonium tris(2-(methoxyimino)propanoato)-tin(ii) dihydrate

    KAUST Repository

    Khanderi, Jayaprakash

    2015-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  19. CCDC 870534: Experimental Crystal Structure Determination : Dichloro-trimethyl-tantalum(v)

    KAUST Repository

    Chen, Yin

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  20. CCDC 963856: Experimental Crystal Structure Determination : catena-[bis(mu2-2-methylimidazole)-zinc

    KAUST Repository

    Shekhah, Osama

    2014-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  1. Experimental determination and modeling of the phase behavior for the direct synthesis of dimethyl carbonate from methanol and carbon dioxide

    DEFF Research Database (Denmark)

    Tsivintzelis, Ioannis; Musko, Nikolai E.; Baiker, Alfons

    2013-01-01

    -Plus-Association (CPA) equation of state was applied to model the phase behavior of the experimentally studied systems. In this regard, the CPA binary interaction parameters were estimated based on experimental data for the corresponding binary systems available in the literature, and subsequently the model was applied......This study focuses on the investigation of the phase behavior of mixtures relevant to the direct synthesis of dimethyl carbonate from methanol and carbon dioxide. The bubble points of corresponding quaternary mixtures of varying composition were experimentally determined. The Cubic...

  2. Study of volumetric properties (PVT) of mixtures made of light hydrocarbons (C1-C4), carbon dioxide and hydrogen sulfide - Experimental measurements through a vibrating tube densimeter and modelling; Etude des proprietes volumetriques (PVT) d'hydrocarbures legers (C1-C4), du dioxyde de carbone et de l'hydrogene sulfure. Mesures par densimetrie a tube vibrant et modelisation

    Energy Technology Data Exchange (ETDEWEB)

    Rivollet, F.

    2005-12-15

    Various pollutant contents (i.e. carbon dioxide, hydrogen sulphide or other sulphur products) are found in produced oils. These latter must undergo a number of transformations and purifications. The design and dimensioning of the corresponding units can well be optimized only if one has reliable and accurate data about phase equilibria and volumetric properties and of course reliable and accurate modeling. This work was devoted partly to measurements of volumetric properties on three binary mixtures (ethane - hydrogen sulphide, ethane - propane and carbon dioxide - hydrogen sulphide). These measurements were carried out using equipment, comprising a vibrating tube densimeter (Paar, model DMA 512 P), which was especially designed and built for this work. The binary mixtures were studied in the 253 to 363 K temperature range from at pressures up to either 20 or 40 MPa. Two calibration methods of the vibrating tube were used: the FPMC method (Forced Path Mechanical Calibration) described in the literature and an original method containing neural network, developed herein. The study undertaken about the modeling of volumetric properties made it possible to highlight the inadequacy of the traditional use of cubic equations of state to represent simultaneously volumetric properties and phase equilibria. Among the equations of state investigated, a close attention however was paid to cubic equations of state because of their very great use in the oil field. A new tool was found to adapt cubic equations of state to the simultaneous and satisfactory representation of volumetric properties and phase equilibria. It concerns the coupling of the cubic Redlich-Kwong-Soave equation of state with volume correction through a neural network. This new model was tested successfully, it makes it possible to benefit from the existing work of representation of phase equilibria (mixing rules and interaction coefficients) while improving calculation of the volumetric data.

  3. Minimization of variation in volumetric shrinkage and deflection on injection molding of Bi-aspheric lens using numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Bensingh, R. Joseph [Central Institute of Plastics Engineering and Technology, Chennai (India); Boopathy, S. Rajendra [College of Engineering, Anna University, Chennai (India); Jebaraj, C. [Vellore Institutes of Technology, Chennai (India)

    2016-11-15

    The profile of a bi-aspheric lens is such a way that the thickness narrows down from center to periphery (convex). Injection molding of these profiles has high shrinkage in localized areas, which results in internal voids or sink marks when the part gets cool down to room temperature. This paper deals with the influence of injection molding process parameters such as mold surface temperature, melt temperature, injection time, V/P Switch over by percentage volume filled, packing pressure, and packing duration on the volumetric shrinkage and deflection. The optimal molding parameters for minimum variation in volumetric shrinkage and deflection of bi-aspheric lens have been determined with the application of computer numerical simulation integrated with optimization. The real experimental work carried out with optimal molding parameters and found to have a shallow and steep surface profile accuracy of 0.14 and 1.57 mm, 21.38-45.66 and 12.28-26.90 μm, 41.56-157.33 and 41.56-157.33 nm towards Radii of curvatures (RoC), surface roughness (Ra) and waviness of the surface profiles (profile error Pt), respectively.

  4. Forensic aspects of gene expression signatures for age determination in bruises as evaluated in an experimental porcine model

    DEFF Research Database (Denmark)

    Barington, Kristiane; Jensen, Henrik Elvang; Skovgaard, Kerstin

    2017-01-01

    was investigated. The aim was to evaluate if expression signatures of selected genes were capable of determining bruises according to age and the force of impact. Eighteen experimental pigs were anesthetized, and on each animal four blunt traumas were inflicted on the back with a low, moderate or high force......Determining the age of bruises and the force used to inflict the trauma is of crucial importance in both human and veterinary forensic pathology. In the present study, the expression of more than 50 different genes in subcutaneous fat and muscle tissue from experimental bruises in pigs...

  5. Experimental determination of the back scattering factor in X-ray microanalysis

    International Nuclear Information System (INIS)

    Derian, J.C.

    1966-06-01

    This paper describes the first experimental method which has fixed the relative value of the X-ray loss by electron back scattering. Measurements have been performed, using gold, copper and aluminium specimens and accelerating voltages from 10 to 30 kV. Our experimental results, although higher than back scattering factor values calculated before, agree fairly well with those obtained by a Monte-Carlo calculation, using recent experimental measurement on thin films. The higher values obtained here, show that the compensation between deceleration and back scattering effects is better: the discrepancy from a linearity law is then probably weaker than it has been generally shown previously. (author) [fr

  6. Volumetric analysis of chronic maxillary atelectasis.

    Science.gov (United States)

    Lin, Giant C; Sedaghat, Ahmad R; Bleier, Benjamin S; Holbrook, Eric H; Busaba, Nicolas Y; Yoon, Michael K; Gray, Stacey T

    2015-01-01

    The relationship between orbit and maxillary sinus volumes in patients with chronic maxillary atelectasis (CMA), commonly known as silent sinus syndrome if enophthalmos is present, is poorly understood. A retrospective review of 22 patients who underwent endoscopic sinus surgery (ESS) for CMA from 2005 to 2013 was performed. Computed tomography (CT) images were analyzed using OsiriX 5.8.2 software for volumetric analysis of the orbit and maxillary sinus at presentation and after surgical treatment with ESS. Pretreatment mean orbit volumes on the diseased side (DS) and the contralateral side (CS) were 29.22 and 26.50 mL, respectively (p Volumetric analysis is a powerful and novel method for objectively demonstrating the degree of orbit expansion and maxillary sinus contraction seen with CMA. Spontaneous maxillary sinus expansion and a decrease in orbit volume can occur after ESS, but post-ESS volumes do not return to the normal volume of the CS.

  7. Volumetric polymerization shrinkage of contemporary composite resins

    OpenAIRE

    Nagem Filho, Halim; Nagem, Haline Drumond; Francisconi, Paulo Afonso Silveira; Franco, Eduardo Batista; Mondelli, Rafael Francisco Lia; Coutinho, Kennedy Queiroz

    2007-01-01

    The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymerization shrinkage of 7 contemporary composite resins (Definite, Suprafill, SureFil, Filtek Z250, Fill ...

  8. Combined surface and volumetric occlusion shading

    KAUST Repository

    Schott, Matthias O.

    2012-02-01

    In this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. © 2012 IEEE.

  9. Volumetric and superficial characterization of carbon activated

    International Nuclear Information System (INIS)

    Carrera G, L.M.; Garcia S, I.; Jimenez B, J.; Solache R, M.; Lopez M, B.; Bulbulian G, S.; Olguin G, M.T.

    2000-01-01

    The activated carbon is the resultant material of the calcination process of natural carbonated materials as coconut shells or olive little bones. It is an excellent adsorbent of diluted substances, so much in colloidal form, as in particles form. Those substances are attracted and retained by the carbon surface. In this work is make the volumetric and superficial characterization of activated carbon treated thermically (300 Centigrade) in function of the grain size average. (Author)

  10. MR volumetric assessment of endolymphatic hydrops

    International Nuclear Information System (INIS)

    Guerkov, R.; Berman, A.; Jerin, C.; Krause, E.; Dietrich, O.; Flatz, W.; Ertl-Wagner, B.; Keeser, D.

    2015-01-01

    We aimed to volumetrically quantify endolymph and perilymph spaces of the inner ear in order to establish a methodological basis for further investigations into the pathophysiology and therapeutic monitoring of Meniere's disease. Sixteen patients (eight females, aged 38-71 years) with definite unilateral Meniere's disease were included in this study. Magnetic resonance (MR) cisternography with a T2-SPACE sequence was combined with a Real reconstruction inversion recovery (Real-IR) sequence for delineation of inner ear fluid spaces. Machine learning and automated local thresholding segmentation algorithms were applied for three-dimensional (3D) reconstruction and volumetric quantification of endolymphatic hydrops. Test-retest reliability was assessed by the intra-class coefficient; correlation of cochlear endolymph volume ratio with hearing function was assessed by the Pearson correlation coefficient. Endolymph volume ratios could be reliably measured in all patients, with a mean (range) value of 15 % (2-25) for the cochlea and 28 % (12-40) for the vestibulum. Test-retest reliability was excellent, with an intra-class coefficient of 0.99. Cochlear endolymphatic hydrops was significantly correlated with hearing loss (r = 0.747, p = 0.001). MR imaging after local contrast application and image processing, including machine learning and automated local thresholding, enable the volumetric quantification of endolymphatic hydrops. This allows for a quantitative assessment of the effect of therapeutic interventions on endolymphatic hydrops. (orig.)

  11. A volumetric data system for environmental robotics

    International Nuclear Information System (INIS)

    Tourtellott, J.

    1994-01-01

    A three-dimensional, spatially organized or volumetric data system provides an effective means for integrating and presenting environmental sensor data to robotic systems and operators. Because of the unstructed nature of environmental restoration applications, new robotic control strategies are being developed that include environmental sensors and interactive data interpretation. The volumetric data system provides key features to facilitate these new control strategies including: integrated representation of surface, subsurface and above-surface data; differentiation of mapped and unmapped regions in space; sculpting of regions in space to best exploit data from line-of-sight sensors; integration of diverse sensor data (for example, dimensional, physical/geophysical, chemical, and radiological); incorporation of data provided at different spatial resolutions; efficient access for high-speed visualization and analysis; and geometric modeling tools to update a open-quotes world modelclose quotes of an environment. The applicability to underground storage tank remediation and buried waste site remediation are demonstrated in several examples. By integrating environmental sensor data into robotic control, the volumetric data system will lead to safer, faster, and more cost-effective environmental cleanup

  12. MR volumetric assessment of endolymphatic hydrops

    Energy Technology Data Exchange (ETDEWEB)

    Guerkov, R.; Berman, A.; Jerin, C.; Krause, E. [University of Munich, Department of Otorhinolaryngology Head and Neck Surgery, Grosshadern Medical Centre, Munich (Germany); University of Munich, German Centre for Vertigo and Balance Disorders, Grosshadern Medical Centre, Marchioninistr. 15, 81377, Munich (Germany); Dietrich, O.; Flatz, W.; Ertl-Wagner, B. [University of Munich, Institute of Clinical Radiology, Grosshadern Medical Centre, Munich (Germany); Keeser, D. [University of Munich, Institute of Clinical Radiology, Grosshadern Medical Centre, Munich (Germany); University of Munich, German Centre for Vertigo and Balance Disorders, Grosshadern Medical Centre, Marchioninistr. 15, 81377, Munich (Germany); University of Munich, Department of Psychiatry and Psychotherapy, Innenstadtkliniken Medical Centre, Munich (Germany)

    2014-10-16

    We aimed to volumetrically quantify endolymph and perilymph spaces of the inner ear in order to establish a methodological basis for further investigations into the pathophysiology and therapeutic monitoring of Meniere's disease. Sixteen patients (eight females, aged 38-71 years) with definite unilateral Meniere's disease were included in this study. Magnetic resonance (MR) cisternography with a T2-SPACE sequence was combined with a Real reconstruction inversion recovery (Real-IR) sequence for delineation of inner ear fluid spaces. Machine learning and automated local thresholding segmentation algorithms were applied for three-dimensional (3D) reconstruction and volumetric quantification of endolymphatic hydrops. Test-retest reliability was assessed by the intra-class coefficient; correlation of cochlear endolymph volume ratio with hearing function was assessed by the Pearson correlation coefficient. Endolymph volume ratios could be reliably measured in all patients, with a mean (range) value of 15 % (2-25) for the cochlea and 28 % (12-40) for the vestibulum. Test-retest reliability was excellent, with an intra-class coefficient of 0.99. Cochlear endolymphatic hydrops was significantly correlated with hearing loss (r = 0.747, p = 0.001). MR imaging after local contrast application and image processing, including machine learning and automated local thresholding, enable the volumetric quantification of endolymphatic hydrops. This allows for a quantitative assessment of the effect of therapeutic interventions on endolymphatic hydrops. (orig.)

  13. TU-F-BRE-05: Experimental Determination of K Factor in Small Field Dosimetry

    International Nuclear Information System (INIS)

    Das, I; Akino, Y; Francescon, P

    2014-01-01

    Purpose: Small-field dosimetry is challenging due to charged-particle disequilibrium, source occlusion and more importantly finite size of detectors. IAEA/AAPM has published approach to convert detector readings to dose by k factor. Manufacturers have been trying to provide various types of micro-detectors that could be used in small fields. However k factors depends on detector perturbations and are derived using Monte Carlo simulation. PTW has introduced a microDiamond for small-field dosimetry. An experimental approach is presented to derive the k factor for this detector. Methods: PTW microDiamond is a small volume detector with 1.1 mm radius and 1.0 micron thick synthetic diamond. Output factors were measured from 1×1cm2 to 12×12 cm2 on a Varian machine at various depths using various micro-detectors with published k factors. Dose is calculated as reading * K. Assuming k factor is accurate, output factor should be identical with every micro-detectors. Hence published k values (Francescon et al Med Phys 35, 504-513,2008) were used to covert readings and then output factors were computed. Based on the converged curve from other detectors, k factor for microDiamond was computed versus field size. Results: Traditional output factors as ratio of readings normalized to 10×10 cm2 differ significantly for micro-detectors for fields smaller than 3×3 cm2 which are now being used extensively. When readings are converted to dose, the output factor is independent of detector. Based on this method, k factor for microDiamond was estimated to be nearly constant 0.993±0.007 over varied field sizes. Conclusion: Our method provides a unique opportunity to determine the k factor for any unknown detector. It is shown that even though k factor depends on machine type due to focal spot, however for fields ≥1×1 cm2 this method provides accurate evaluation of k factor. Additionally microDiamond could be used with assumption that k factor is nearly unity

  14. Experimental Characterization and Hygroscopicity Determination of Secondary Aerosol from D5 Cyclic Siloxane Oxidation

    Science.gov (United States)

    Stanier, C. O.; Janechek, N. J.; Bryngelson, N.; Marek, R. F.; Lersch, T.; Bunker, K.; Casuccio, G.; Brune, W. H.; Hornbuckle, K. C.

    2017-12-01

    Cyclic volatile methyl siloxanes are anthropogenic chemicals present in personal care products such as antiperspirants and lotions. These are volatile chemicals that are readily released into the atmosphere by product use. Due to their emission and relatively slow kinetics of their major transformation pathway, reaction with hydroxyl radicals (OH), these compounds are present in high concentrations in indoor environments and widespread in outdoor environments. Cyclic siloxane reaction with OH can lead to secondary organic aerosols, and due to the widespread prevalence of the parent compounds, may be an important source of ambient aerosols. Atmospheric aerosols have important influences to the climate by affecting the radiative balance and by serving as cloud condensation nuclei (CCN) which influence clouds. While the parent compounds have been well-studied, the oxidation products have received much less attention, with almost no ambient measurements or experimental physical property data. We report physical properties of aerosols generated by reacting the cyclic siloxane D5 with OH using a Potential Aerosol Mass (PAM) photochemical chamber. The particles were characterized by SMPS, imaging and elemental analysis using both Transmission Electron Microscopy and Scanning Transmission Electron Microscopy equipped with Energy Dispersive X-ray Spectroscopy systems (TEM-EDS and STEM-EDS), volatility measurements using Volatility Tandem Differential Mobility Analyzer (V-TDMA), and hygroscopicity measurements to determine CCN potential using a Droplet Measurement Technologies Cloud Condensation Nuclei Counter (DMT-CCN). Aerosol yield sensitivity to D5 and OH concentrations, residence time, and seed aerosols were analyzed. TEM-EDS and STEM-EDS analysis show spherical particle morphology with elemental composition consistent with aerosols derived from cyclic siloxane sources. Measured aerosol yields were 20-50% with typical aerosol concentrations 300,000 particles cm-3, up to

  15. Volumetric 3D Display System with Static Screen

    Science.gov (United States)

    Geng, Jason

    2011-01-01

    Current display technology has relied on flat, 2D screens that cannot truly convey the third dimension of visual information: depth. In contrast to conventional visualization that is primarily based on 2D flat screens, the volumetric 3D display possesses a true 3D display volume, and places physically each 3D voxel in displayed 3D images at the true 3D (x,y,z) spatial position. Each voxel, analogous to a pixel in a 2D image, emits light from that position to form a real 3D image in the eyes of the viewers. Such true volumetric 3D display technology provides both physiological (accommodation, convergence, binocular disparity, and motion parallax) and psychological (image size, linear perspective, shading, brightness, etc.) depth cues to human visual systems to help in the perception of 3D objects. In a volumetric 3D display, viewers can watch the displayed 3D images from a completely 360 view without using any special eyewear. The volumetric 3D display techniques may lead to a quantum leap in information display technology and can dramatically change the ways humans interact with computers, which can lead to significant improvements in the efficiency of learning and knowledge management processes. Within a block of glass, a large amount of tiny dots of voxels are created by using a recently available machining technique called laser subsurface engraving (LSE). The LSE is able to produce tiny physical crack points (as small as 0.05 mm in diameter) at any (x,y,z) location within the cube of transparent material. The crack dots, when illuminated by a light source, scatter the light around and form visible voxels within the 3D volume. The locations of these tiny voxels are strategically determined such that each can be illuminated by a light ray from a high-resolution digital mirror device (DMD) light engine. The distribution of these voxels occupies the full display volume within the static 3D glass screen. This design eliminates any moving screen seen in previous

  16. Green chemistry volumetric titration kit for pharmaceutical formulations: Econoburette

    Directory of Open Access Journals (Sweden)

    Man Singh

    2009-08-01

    Full Text Available Stopcock SC and Spring Sp models of Econoburette (Calibrated, RTC (NR, Ministry of Small Scale Industries, Government of India, developed for semimicro volumetric titration of pharmaceutical formulations are reported. These are economized and risk free titration where pipette is replaced by an inbuilt pipette and conical flask by inbuilt bulb. A step of pipetting of stock solution by mouth is deleted. It is used to allow solution exposure to user’s body. This risk is removed and even volatile and toxic solutions are titrated with full proof safety. Econoburette minimizes use of materials and time by 90 % and prevent discharge of polluting effluent to environment. Few acid and base samples are titrated and an analysis of experimental expenditure is described in the papers.

  17. Experimental determination of bottom relief on the basis of studies of the lower part of the river Samara

    OpenAIRE

    Dubovyk, Denys; Borokhovych, Yulii

    2017-01-01

    Experimentally determine the bottom relief on the basis of studies of the lower section of the river. Samara. To build a route for measuring depths and digitizing depths, we used the built-in Android application, Androzik. Along with measurements of depths, water turbidity and sedimentation rate were determined. About 2,000 depth points were obtained, the data was transferred to the GIS platform, resulting in a bottom relief model, the area and volume of the reservoir. Laboratory tests of wat...

  18. Experimental determination of organic liquid fuels heating value as function of the humidity; Determinacao experimental do poder calorifico de combustiveis organicos liquidos em funcao da umidade

    Energy Technology Data Exchange (ETDEWEB)

    Lyrio, Aristoteles Alves; Dalvi, Elias Antonio; Vieira, Renata da Cruz Araujo [Espirito Santo Univ., Vitoria, ES (Brazil). Dept. de Engenharia Mecanica

    1998-07-01

    This work presents experimental results for higher heating value (HHV) and lower heating value (LHV) of organic liquid fuels sold in gas stations situated at Vitoria Metropolitan Area in the state of Espirito Santo, Brazil. Experiments were conduced showing the influence of fuel water contents on the HHV and LHV such as gasoline, diesel oil, kerosene and alcohol, covering a wide range of humidity (0 to 70%). A correlation between higher heating value and the water content in the fuel was determined for the experimental data obtained. The main conclusion of the present work has shown that the content of water in the fuel makes its higher heating value to decrease in the same proportion as the value of the humidity (ratio between mass of water and mass of fuel mass of water), and so, it is very important to control the level of humidity in the fuel in order to avoid significant losses of heat released during the fuel combustion. (author)

  19. Comparison between the volumetric flow rate and pressure distribution for different kinds of sliding thrust bearing

    Directory of Open Access Journals (Sweden)

    O. Pourmehran

    2015-06-01

    Full Text Available In this paper a hydrodynamic journal sliding bearing, forming with two nonparallel surfaces that the lower surface moves with a unidirectional velocity and the upper surface is stationary shaped with exponential geometry is verified mathematically. The values of volumetric flow rate and distribution of pressure for incompressible lubricant flow between two supports in several conditions of velocity with different variables are determined. The results indicate that by increasing the amount of constant (m, the maximum oil pressure in the bearing will face an extreme decrease, and also by increasing the α coefficient, the rate of volumetric flow rate will decrease.

  20. Advances in theoretical and experimental XAFS studies of thermodynamic properties, anharmonic effects and structural determination of fcc crystals

    Science.gov (United States)

    Hung, Nguyen Van; Thang, Cu Sy; Duc, Nguyen Ba; Vuong, Dinh Quoc; Tien, Tong Sy

    2017-12-01

    Thermodynamic properties, anharmonic effects and structural determination of fcc crystals have been studied based on the theoretical and experimental Debye-Waller factors presented in terms of cumulant expansion up to the third order, thermal expansion coefficient, X-ray absorption fine structure (XAFS) spectra and their Fourier transform magnitudes. The advances in these studies are performed by the further development of the anharmonic correlated Einstein model primary only for approximating three first XAFS cumulants into the method using that all the considered theoretical and experimental XAFS parameters have been provided based on only the calculated and measured second cumulants. The obtained cumulants describe the anharmonic effects in XAFS contributing to the accurate structural determination. Numerical results for Cu are found to be in good agreement with the experimental values extracted by using the present advanced method and with those obtained by the other measurements.

  1. Experimental determination of nanofluid specific heat with SiO2 nanoparticles in different base fluids

    Science.gov (United States)

    Akilu, S.; Baheta, A. T.; Sharma, K. V.; Said, M. A.

    2017-09-01

    Nanostructured ceramic materials have recently attracted attention as promising heat transfer fluid additives owing to their outstanding heat storage capacities. In this paper, experimental measurements of the specific heats of SiO2-Glycerol, SiO2-Ethylene Glycol, and SiO2-Glycerol/Ethylene Glycol mixture 60:40 ratio (by mass) nanofluids with different volume concentrations of 1.0-4.0% have been carried out using differential scanning calorimeter at temperatures of 25 °C and 50 °C. Experimental results indicate lower specific heat capacities are found with SiO2 nanofluids compared to their respective base fluids. The specific heat was decreasing with the increase of concentration, and this decrement depends on upon the type of the base fluid. It is observed that temperature has a positive impact on the specific heat capacity. Furthermore, the experimental values were compared with the theoretical model predictions, and a satisfactory agreement was established.

  2. Automated volumetric breast density estimation: A comparison with visual assessment

    International Nuclear Information System (INIS)

    Seo, J.M.; Ko, E.S.; Han, B.-K.; Ko, E.Y.; Shin, J.H.; Hahn, S.Y.

    2013-01-01

    Aim: To compare automated volumetric breast density (VBD) measurement with visual assessment according to Breast Imaging Reporting and Data System (BI-RADS), and to determine the factors influencing the agreement between them. Materials and methods: One hundred and ninety-three consecutive screening mammograms reported as negative were included in the study. Three radiologists assigned qualitative BI-RADS density categories to the mammograms. An automated volumetric breast-density method was used to measure VBD (% breast density) and density grade (VDG). Each case was classified into an agreement or disagreement group according to the comparison between visual assessment and VDG. The correlation between visual assessment and VDG was obtained. Various physical factors were compared between the two groups. Results: Agreement between visual assessment by the radiologists and VDG was good (ICC value = 0.757). VBD showed a highly significant positive correlation with visual assessment (Spearman's ρ = 0.754, p < 0.001). VBD and the x-ray tube target was significantly different between the agreement group and the disagreement groups (p = 0.02 and 0.04, respectively). Conclusion: Automated VBD is a reliable objective method to measure breast density. The agreement between VDG and visual assessment by radiologist might be influenced by physical factors

  3. Experimental determination of configurational entropy in a two-dimensional liquid under random pinning

    Science.gov (United States)

    Williams, Ian; Turci, Francesco; Hallett, James E.; Crowther, Peter; Cammarota, Chiara; Biroli, Giulio; Royall, C. Patrick

    2018-03-01

    A quasi two-dimensional colloidal suspension is studied under the influence of immobilisation (pinning) of a random fraction of its particles. We introduce a novel experimental method to perform random pinning and, with the support of numerical simulation, we find that increasing the pinning concentration smoothly arrests the system, with a cross-over from a regime of high mobility and high entropy to a regime of low mobility and low entropy. At the local level, we study fluctuations in area fraction and concentration of pins and map them to entropic structural signatures and local mobility, obtaining a measure for the local entropic fluctuations of the experimental system.

  4. Stability and Volumetric Properties of Asphalt Mixture Containing Waste Plastic

    Directory of Open Access Journals (Sweden)

    Abd Kader Siti Aminah

    2017-01-01

    Full Text Available The objectives of this study are to determine the optimum bitumen content (OBC for every percentage added of waste plastics in asphalt mixtures and to investigate the stability properties of the asphalt mixtures containing waste plastic. Marshall stability and flow values along with density, air voids in total mix, voids in mineral aggregate, and voids filled with bitumen were determined to obtain OBC at different percentages of waste plastic, i.e., 4%, 6%, 8%, and 10% by weight of bitumen as additive. Results showed that the OBC for the plastic-modified asphalt mixtures at 4%, 6%, 8%, and 10% are 4.98, 5.44, 5.48, and 5.14, respectively. On the other hand, the controlled specimen’s shows better volumetric properties compared to plastic mixes. However, 4% additional of waste plastic indicated better stability than controlled specimen.

  5. Determination of the physical parameters distribution in spin transition compounds using experimental FORC diagram

    International Nuclear Information System (INIS)

    Tanasa, Radu; Linares, Jorge; Enachescu, Cristian; Varret, Francois; Stancu, Alexandru

    2006-01-01

    Spin transitions materials are characterized with an innovative experimental method, i.e. first-order reversal curve (FORC) diagram. The interpretation of the results is performed in the framework of two different Ising-like models: a mean-field approach and the exact solution done by the Monte Carlo entropic sampling (MCES) method

  6. Experimental determination of demand side management potential of wet appliances in the Netherlands

    NARCIS (Netherlands)

    Staats, M. R.; de Boer-Meulman, P. D M; van Sark, W. G J H M|info:eu-repo/dai/nl/074628526

    2017-01-01

    The potential of demand side management (DSM) of wet appliances (washing machine, dishwasher and tumble dryer) in households with photovoltaic (PV) systems is studied experimentally focusing on evening peak demand reduction and increase in PV self-consumption. In a sample of 100 Dutch households the

  7. Experimental Determination of the Formation Enthalpy of Calcium Cobaltate from Sol–Gel Precursors

    DEFF Research Database (Denmark)

    Holgate, Tim C.; Wu, NingYu; Van Nong, Ngo

    2017-01-01

    for thermoelectric efficiency, there remains a gap in the knowledge, both experimental and theoretical, of the thermodynamics of the system. Presented herein is an analysis of the heat of formation of the Ca3Co4O9 phase from sol–gel precursors using a highly sensitive differential scanning calorimeter, as well...

  8. Failure mode and effect analysis experimental reliability determination for the CANDU reactor equipment

    International Nuclear Information System (INIS)

    Vieru, G.

    1996-01-01

    This paper describes the experimental tests performed in order to prove the reliability parameters for certain equipment manufactured in INR Pitesti, for NPP Cernavoda. The tests were provided by Technical Specifications and test procedures. A comparison, referring to the reliability parameters, between Canadian equipment and INR manufactured equipment ones is also given. The results of tests and conclusions are shown. (author)

  9. Experimental determination of ideal concrete density used for applications in bunkers

    International Nuclear Information System (INIS)

    Bitelli, T.; Coelho, G.M.

    1988-01-01

    Comparisons between barite concrete of different densities and exactly equal measures, subjected to gamma irradiation of 192 Ir source, with changeless measure of geometry are presented. The experimental results and the applied statistics with 95% of trust, confirm that the barite added supplies a significant increase of irradiation attenuation. (C.M.) [pt

  10. Experimental determination of the quasiparticle decay length ξqp in a diffusive superconducting quantum well

    NARCIS (Netherlands)

    Magnée, P.H.C.; Hartog, S.G. den; Wees, B.J. van; Klapwijk, T.M.

    1995-01-01

    We have experimentally investigated the electronic transport properties of an AlSb/InAs/AlSb quantum well, where part of the AlSb top layer has been replaced with a superconducting Nb strip. By doing a transmission experiment underneath the Nb strip and comparing the results with a model based on

  11. Experimental determination of the fluid velocity by spectral analysis of temperature fluctuations

    International Nuclear Information System (INIS)

    Foucrier, M.J.; Faya, A.J.G.

    1988-12-01

    Local velocities of turbulent closed channel flow were measured applying the noise analysis technique to signals coming from two sensors separated by a know distance. Good agreement was found when comparing experimental data to more accurate measurements. Ranges of Reynolds number and thermocouple spacial separation are recommended. (author) [pt

  12. Experimental determination of the unattached radon daughter fraction and dust size distribution in some Canadian uranium mines

    International Nuclear Information System (INIS)

    Bigu, J.; Kirk, J.

    1982-01-01

    The unattached radon daughter fraction has been experimentally determined in some Canadian uranium mines. Two experimental methods have been used, the wire screen method and a diffusion sampler based on Mercer's theory of diffusional deposition on parallel circular plates. Experiments were conducted in 'non-diesel' and 'diesel' areas of the mines, i.e. locations where mining was done with diesel machinery. Unattached fractions ranged from about 2-8 per cent for non-diesel area. For diesel areas the unattached fraction was substantially lower, less than about one per cent. The aerosol concentration in the range 0.0015 - 0.13 μm was measured with a condensation nuclei counter. Dust concentration was determined with conventional samplers. Particle size distribution in the respirable range was determined with a fine particle spectrometer in conjunction with eriometric techniques

  13. Determinants for swine mycoplasmal pneumonia reproduction under experimental conditions: A systematic review and recursive partitioning analysis

    Science.gov (United States)

    Garcia-Morante, Beatriz; Segalés, Joaquim; Serrano, Emmanuel

    2017-01-01

    One of the main Mycoplasma hyopneumoniae (M. hyopneumoniae) swine experimental model objectives is to reproduce mycoplasmal pneumonia (MP). Unfortunately, experimental validated protocols to maximize the chance to successfully achieve lung lesions induced by M. hyopneumoniae are not available at the moment. Thus, the objective of this work was to identify those factors that might have a major influence on the effective development of MP, measured as macroscopic lung lesions, under experimental conditions. Data from 85 studies describing M. hyopneumoniae inoculation experiments were compiled by means of a systematic review and analyzed thereafter. Several variables were considered in the analyses such as the number of pigs in the experiment, serological status against M. hyopneumoniae, source of the animals, age at inoculation, type of inoculum, strain of M. hyopneumoniae, route, dose and times of inoculation, study duration and co-infection with other swine pathogens. Descriptive statistics were used to depict M. hyopneumoniae experimental model main characteristics whereas a recursive partitioning approach, using regression trees, assessed the importance of the abovementioned experimental variables as MP triggering factors. A strong link between the time period between challenge and necropsies and lung lesion severity was observed. Results indicated that the most important factors to explain the observed lung lesion score variability were: (1) study duration, (2) M. hyopneumoniae strain, (3) age at inoculation, (4) co-infection with other swine pathogens and (5) animal source. All other studied variables were not relevant to explain the variability on M. hyopneumoniae lung lesions. The results provided in the present work may serve as a basis for debate in the search for a universally accepted M. hyopneumoniae challenge model. PMID:28742802

  14. Determinants for swine mycoplasmal pneumonia reproduction under experimental conditions: A systematic review and recursive partitioning analysis.

    Directory of Open Access Journals (Sweden)

    Beatriz Garcia-Morante

    Full Text Available One of the main Mycoplasma hyopneumoniae (M. hyopneumoniae swine experimental model objectives is to reproduce mycoplasmal pneumonia (MP. Unfortunately, experimental validated protocols to maximize the chance to successfully achieve lung lesions induced by M. hyopneumoniae are not available at the moment. Thus, the objective of this work was to identify those factors that might have a major influence on the effective development of MP, measured as macroscopic lung lesions, under experimental conditions. Data from 85 studies describing M. hyopneumoniae inoculation experiments were compiled by means of a systematic review and analyzed thereafter. Several variables were considered in the analyses such as the number of pigs in the experiment, serological status against M. hyopneumoniae, source of the animals, age at inoculation, type of inoculum, strain of M. hyopneumoniae, route, dose and times of inoculation, study duration and co-infection with other swine pathogens. Descriptive statistics were used to depict M. hyopneumoniae experimental model main characteristics whereas a recursive partitioning approach, using regression trees, assessed the importance of the abovementioned experimental variables as MP triggering factors. A strong link between the time period between challenge and necropsies and lung lesion severity was observed. Results indicated that the most important factors to explain the observed lung lesion score variability were: (1 study duration, (2 M. hyopneumoniae strain, (3 age at inoculation, (4 co-infection with other swine pathogens and (5 animal source. All other studied variables were not relevant to explain the variability on M. hyopneumoniae lung lesions. The results provided in the present work may serve as a basis for debate in the search for a universally accepted M. hyopneumoniae challenge model.

  15. L X-ray fluorescence cross sections experimentally determined for elements with 45

    Energy Technology Data Exchange (ETDEWEB)

    Bonzi, Edgardo V., E-mail: bonzie@famaf.unc.edu.ar [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Ciudad Universitaria-5010, Cordoba (Argentina); Badiger, Nagappa M. [Departments of Physics, Karnatak University, Dharwad 580 003, Karnataka (India); Grad, Gabriela B. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Ciudad Universitaria-5010, Cordoba (Argentina); Barrea, Raul A. [The Biophysics Collaborative Access Team (BioCAT), Dept of Biological Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616 (United States); Figueroa, Rodolo G. [Departamento de Cs. Fisicas, Universidad de La Frontera, Temuco (Chile)

    2012-04-15

    Experimental determination of L fluorescence cross-sections for elements with 45determined at 9 keV using Synchrotron radiation. This work is part of an investigation we did at low energies in the same group of elements. The individual L X-ray photons, Ll, L{alpha}, L{beta}{sub I}, L{beta}{sub II}, L{gamma}{sub {Iota}} and L{gamma}{sub {Iota}{Iota}} produced in the target were measured using a Si(Li) detector. The experimental set-up provided a low background by using linearly polarized monoenergetic photon beam, improving the signal-to-noise ratio. The experimental cross sections obtained in this work were compared with data calculated using coefficients from , , and Scofield and Puri et al. (1993, 1995) - Highlights: Black-Right-Pointing-Pointer Experimental data of L fluorescence cross-sections with 45determined at 9 keV by Synchrotron radiation. Black-Right-Pointing-Pointer The cross sections Ll, L{alpha}, L{beta}{sub I}, L{beta}{sub II}, L{gamma}{sub {Iota}} and L{gamma}{sub {Iota}{Iota}} obtained, were compared with calculated data. Black-Right-Pointing-Pointer The Hypermet function was used to fit the data, because it considers a tail on the left side of the peak. Black-Right-Pointing-Pointer The tail is relevant when a small peak has another one on the right side with a big area.

  16. A convenient method and numerical tables for sample size determination in longitudinal-experimental research using multilevel models.

    Science.gov (United States)

    Usami, Satoshi

    2014-12-01

    Recent years have shown increased awareness of the importance of sample size determination in experimental research. Yet effective and convenient methods for sample size determination, especially in longitudinal experimental design, are still under development, and application of power analysis in applied research remains limited. This article presents a convenient method for sample size determination in longitudinal experimental research using a multilevel model. A fundamental idea of this method is transformation of model parameters (level 1 error variance [σ(2)], level 2 error variances [τ 00, τ 11] and its covariance [τ 01, τ 10], and a parameter representing experimental effect [δ]) into indices (reliability of measurement at the first time point [ρ 1], effect size at the last time point [Δ T ], proportion of variance of outcomes between the first and the last time points [k], and level 2 error correlation [r]) that are intuitively understandable and easily specified. To foster more convenient use of power analysis, numerical tables are constructed that refer to ANOVA results to investigate the influence on statistical power by respective indices.

  17. Sensitivity of the interpretation of the experimental ion thermal diffusivity to the determination of the ion conductive heat flux

    International Nuclear Information System (INIS)

    Stacey, W. M.

    2014-01-01

    A moments equation formalism for the interpretation of the experimental ion thermal diffusivity from experimental data is used to determine the radial ion thermal conduction flux that must be used to interpret the measured data. It is shown that the total ion energy flux must be corrected for thermal and rotational energy convection, for the work done by the flowing plasma against the pressure and viscosity, and for ion orbit loss of particles and energy, and expressions are presented for these corrections. Each of these factors is shown to have a significant effect on the interpreted ion thermal diffusivity in a representative DIII-D [J. Luxon, Nucl. Fusion 42, 614 (2002)] discharge

  18. Experimental determination of linear attenuation coefficient of normal, benign and malignant breast tissues

    Energy Technology Data Exchange (ETDEWEB)

    Tomal, A., E-mail: alessandra_tomal@yahoo.com.b [Departamento de Fisica e Matematica, FFCLRP, Universidade de Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto 14040-901, Sao Paulo (Brazil); Mazarro, I. [Departamento de Fisica, LORXI, PO Box 19091, Universidade Federal do Parana, Curitiba, 81531-000, Parana (Brazil); Kakuno, E.M. [Centro de Ciencias Exatas e Tecnologicas, UFPel/UNIPAMPA, Bage, 96400-970, Rio Grande do Sul (Brazil); Poletti, M.E. [Departamento de Fisica e Matematica, FFCLRP, Universidade de Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto 14040-901, Sao Paulo (Brazil)

    2010-10-15

    The linear attenuation coefficients for normal (adipose and glandular) and neoplastic (benign and malignant) breast tissues were measured using monoenergetic X-ray beams at the energy range of 8-30 keV, combining narrow beam geometry and high energy resolution obtained using a diffracted X-ray beam. The measured values are compared with predicted ones calculated according to the mixture rule and with previous experimental data showing a good agreement within the experimental uncertainties. Our results show that there is some degree of overlap among glandular, benign and malignant values. Nevertheless, significant differences (p < 0.05) exist in the linear attenuation coefficient between glandular and malignant at energies below 28 keV. Finally, a fitting procedure was applied to values for each group (mean and extremes values) in order to summarize all data.

  19. Theoretical Prediction and Experimental Determination of Heating Time During High-Temperature Heat Treatment of Wood

    Directory of Open Access Journals (Sweden)

    LIU Xin-you

    2011-06-01

    Full Text Available Theoretical prediction provides basic understanding and guidance to correctly implement a certaintechnology in the production process. The present study uses a differential equation to predict the heattransfer time between the surface and core layer of wood during the heat treatment, with applicability inestimating the duration of heat treatments at high temperatures. The obtained prediction was compared withthe result of an experimental study performed on Chinese poplar wood with various thicknesses (20, 40 and60mm. During this experiment, the time necessary for the core of wood to reach a temperature of 100°C,130°C and finally 180°C was monitored and the recorded values were compared with the predicted ones.The result of this comparison proved that the experimental values matched the theoretically predicted times,validating thus the applicability of the proposed equation as prediction tool.

  20. Theoretical and experimental determination of phloem translocation speeds in gymnosperm and angiosperm trees

    DEFF Research Database (Denmark)

    Liesche, Johannes; Jensen, K.; Minchin, P.

    2013-01-01

    In trees, carbohydrates produced in photosynthesizing leaves are transported to roots and other sink organs over distances of up to 100 m inside a specialized transport tissue, the phloem. Carbohydrate translocation in the phloem is a fundamental aspect of tree physiology with relevance for tree...... crop performance and climate change. In this paper, we present theoretical and experimental data on the carbohydrate transport speed inside the phloem....

  1. Experimental study on the determination of small strain-shear modulus of loess soil

    Directory of Open Access Journals (Sweden)

    Mona El Mosallamy

    2016-08-01

    Test results also show that (Gmax increases with the increase of confining pressure and relative density. The change in damping properties is not significant under the effect of silt content and water content, and it reduces slightly with the increase of confining pressure and relative density. Empirical equations based on the results of the experimental work were proposed to predict (Gmax with respect to (Cp, voids ratio and applied pressure.

  2. Determination of nitrogen in coal macerals using electron microprobe technique-experimental procedure

    Science.gov (United States)

    Mastalerz, Maria; Gurba, L.W.

    2001-01-01

    This paper discusses nitrogen determination with the Cameca SX50 electron microprobe using PCO as an analyzing crystal. A set of conditions using differing accelerating voltages, beam currents, beam sizes, and counting times were tested to determine parameters that would give the most reliable nitrogen determination. The results suggest that, for the instrumentation used, 10 kV, current 20 nA, and a counting time of 20 s provides the most reliable nitrogen determination, with a much lower detection limit than the typical concentration of this element in coal. The study demonstrates that the electron microprobe technique can be used to determine the nitrogen content of coal macerals successfully and accurately. ?? 2001 Elsevier Science B.V. All rights reserved.

  3. Experimental determination of the heat transfer coefficient in shell-and-tube condensers using the Wilson plot method

    Science.gov (United States)

    Havlik, Jan; Dlouhy, Tomas

    This article deals with the experimental determination of heat transfer coefficients. The calculation of heat transfer coefficients constitutes a crucial issue in design and sizing of heat exchangers. The Wilson plot method and its modifications based on measured experimental data utilization provide an appropriate tool for the analysis of convection heat transfer processes and the determination of convection coefficients in complex cases. A modification of the Wilson plot method for shell-and-tube condensers is proposed. The original Wilson plot method considers a constant value of thermal resistance on the condensation side. The heat transfer coefficient on the cooling side is determined based on the change in thermal resistance for different conditions (fluid velocity and temperature). The modification is based on the validation of the Nusselt theory for calculating the heat transfer coefficient on the condensation side. A change of thermal resistance on the condensation side is expected and the value is part of the calculation. It is possible to improve the determination accuracy of the criterion equation for calculation of the heat transfer coefficient using the proposed modification. The criterion equation proposed by this modification for the tested shell-and-tube condenser achieves good agreement with the experimental results and also with commonly used theoretical methods.

  4. Automated MRI Volumetric Analysis in Epilepsy Patients with Rasmussen’s Syndrome

    Science.gov (United States)

    Wang, Z. Irene; Krishnan, Balu; Shattuck, David W; Leahy, Richard M; Moosa, Ahsan NV; Wyllie, Elaine; Burgess, Richard C; Al-Sharif, Noor B; Joshi, Anand A; Alexopoulos, Andreas V; Mosher, John C; Udayasankar, Unni; Jones, Stephen E

    2016-01-01

    Background and Purpose To apply automated quantitative volumetric MRI analyses to patients diagnosed with Rasmussen’s encephalitis (RE), to determine the predictive value of lobar volumetric measures, and to assess regional atrophy difference and monitor disease progression using these measures. Materials and Methods Nineteen patients (42 scans) with diagnosed RE were studied. Two control groups were used: one with 42 age- and gender-matched normal subjects; the other with 42 non-RE epilepsy patients with the same disease duration as RE patients. Volumetric analysis was performed on T1-weighted images using BrainSuite. Ratios of volumes from the affected hemisphere divided by those from the unaffected hemisphere were used as input to a logistic regression classifier, which was trained to discriminate patients from controls. Using the classifier, we compared the predictive accuracy of all the volumetric measures. These ratios were further used to assess regional atrophy difference and to correlate with epilepsy duration. Results Interhemispheric and frontal lobe ratios had the best prediction accuracy to separate RE patients from normal and non-RE epilepsy controls. The insula showed significantly more atrophy compared to all the other cortical regions. Patients with longitudinal scans showed progressive volume loss of the affected hemisphere. Atrophy of the frontal lobe and insula correlated significantly with epilepsy duration. Conclusions Automated quantitative volumetric analysis provides accurate separation of RE patients from normal controls and non-RE epilepsy patients, and thus may assist diagnosis of RE. Volumetric analysis could also be included as part of followup for RE patients to assess disease progression. PMID:27609620

  5. Short-term mechanisms influencing volumetric brain dynamics

    Directory of Open Access Journals (Sweden)

    Nikki Dieleman

    2017-01-01

    Full Text Available With the use of magnetic resonance imaging (MRI and brain analysis tools, it has become possible to measure brain volume changes up to around 0.5%. Besides long-term brain changes caused by atrophy in aging or neurodegenerative disease, short-term mechanisms that influence brain volume may exist. When we focus on short-term changes of the brain, changes may be either physiological or pathological. As such determining the cause of volumetric dynamics of the brain is essential. Additionally for an accurate interpretation of longitudinal brain volume measures by means of neurodegeneration, knowledge about the short-term changes is needed. Therefore, in this review, we discuss the possible mechanisms influencing brain volumes on a short-term basis and set-out a framework of MRI techniques to be used for volumetric changes as well as the used analysis tools. 3D T1-weighted images are the images of choice when it comes to MRI of brain volume. These images are excellent to determine brain volume and can be used together with an analysis tool to determine the degree of volume change. Mechanisms that decrease global brain volume are: fluid restriction, evening MRI measurements, corticosteroids, antipsychotics and short-term effects of pathological processes like Alzheimer's disease, hypertension and Diabetes mellitus type II. Mechanisms increasing the brain volume include fluid intake, morning MRI measurements, surgical revascularization and probably medications like anti-inflammatory drugs and anti-hypertensive medication. Exercise was found to have no effect on brain volume on a short-term basis, which may imply that dehydration caused by exercise differs from dehydration by fluid restriction. In the upcoming years, attention should be directed towards studies investigating physiological short-term changes within the light of long-term pathological changes. Ultimately this may lead to a better understanding of the physiological short-term effects of

  6. Optical Addressing of Multi-Colour Photochromic Material Mixture for Volumetric Display

    Science.gov (United States)

    Hirayama, Ryuji; Shiraki, Atsushi; Naruse, Makoto; Nakamura, Shinichiro; Nakayama, Hirotaka; Kakue, Takashi; Shimobaba, Tomoyoshi; Ito, Tomoyoshi

    2016-08-01

    This is the first study to demonstrate that colour transformations in the volume of a photochromic material (PM) are induced at the intersections of two control light channels, one controlling PM colouration and the other controlling decolouration. Thus, PM colouration is induced by position selectivity, and therefore, a dynamic volumetric display may be realised using these two control lights. Moreover, a mixture of multiple PM types with different absorption properties exhibits different colours depending on the control light spectrum. Particularly, the spectrum management of the control light allows colour-selective colouration besides position selectivity. Therefore, a PM-based, full-colour volumetric display is realised. We experimentally construct a mixture of two PM types and validate the operating principles of such a volumetric display system. Our system is constructed simply by mixing multiple PM types; therefore, the display hardware structure is extremely simple, and the minimum size of a volume element can be as small as the size of a molecule. Volumetric displays can provide natural three-dimensional (3D) perception; therefore, the potential uses of our system include high-definition 3D visualisation for medical applications, architectural design, human-computer interactions, advertising, and entertainment.

  7. The Experimental Determination of Thermal Neutron Flux in the Radiochemistry Curriculum

    Science.gov (United States)

    Grant, Patrick M.

    1977-01-01

    Describes an experiment for determining the thermal neutron flux of the light-water nuclear reactor at the University of California, Irvine. The difficulty of the activity can be varied to match the student's level of proficiency. (SL)

  8. Effective cross-section for dimuon production and experimental determination of the hadronic structure functions

    International Nuclear Information System (INIS)

    Weisz, S.

    1982-07-01

    High mass dimuon hadronic production is studied. This study is aimed at pion structure determination. The device is presented. The accessible luminosity is more than one scale order beyond the preceeding experiment one. The performant beam, the great acceptance and the good high mass dimuon selection are described. Parton model is introduced. Drell-Yann mechanism is reviewed. Hadronic structure, revealed during high mass muon pair production, is presented. In particular, pion structure is determined [fr

  9. Ex vivo determined experimental correction factor for the ultrasonic source term in the bioheat equation.

    Science.gov (United States)

    Cortela, Guillermo A; Pereira, Wagner C A; Negreira, Carlos A

    2018-01-01

    The objective of this work is to propose an effective absorption coefficient (α effec ) as an empirical correction factor in the source term of the bioheat equation. The temperature rise in biological tissue due to ultrasound insonification is produced by energy absorption. Usually, the ultrasonic absorption coefficient (α A ) is used as a source term in the bioheat equation to quantify the temperature rise, and the effect of scattering is disregarded. The coefficient α effec includes the scattering contribution as an additional absorption term and should allow us to make a better estimation of the thermal dose (TD), which is important for clinical applications. We simulated the bioheat equation with the source term considering α A or α effec , and with heating provided by therapeutic ultrasound (1MHz, 2.0Wcm -2 ) for about 5.5min (temperature range 36-46°C). Experimental data were obtained in similar heating conditions for a bovine muscle tissue (ex vivo) and temperature curves were measured for depths 7, 30, 35, 40 and 45mm. The TD values from the experimental temperature curves at each depth were compared with the numerical solution of the bioheat equation with the classical and corrected source terms. The highest percentual difference between simulated and experimental TD was 42.5% when assuming the classical α A , and 8.7% for the corrected α effec . The results show that the effective absorption coefficient is a feasible parameter to improve the classical bioheat transfer model, especially for depths larger than the mean free propagation path. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Determination of pKa and the corresponding structures of quinclorac using combined experimental and theoretical approaches

    Science.gov (United States)

    Song, Dean; Sun, Huiqing; Jiang, Xiaohua; Kong, Fanyu; Qiang, Zhimin; Zhang, Aiqian; Liu, Huijuan; Qu, Jiuhui

    2018-01-01

    As an emerging environmental contaminant, the herbicide quinclorac has attracted much attention in recent years. However, a very fundamental issue, the acid dissociation of quinclorac has not yet to be studied in detail. Herein, the pKa value and the corresponding structures of quinclorac were systematically investigated using combined experimental and theoretical approaches. The experimental pKa of quinclorac was determined by the spectrophotometric method to be 2.65 at 25 °C with ionic strength of 0.05 M, and was corrected to be 2.56 at ionic strength of zero. The molecular structures of quinclorac were then located by employing the DFT calculation. The anionic quinclorac was directly located with the carboxylic group perpendicular to the aromatic ring, while neutral quinclorac was found to be the equivalent twin structures. The result was further confirmed by analyzing the UV/Vis and MS-MS2 spectra from both experimental and theoretical viewpoints. By employing the QSPR approach, the theoretical pKa of QCR was determined to be 2.50, which is excellent agreement with the experimental result obtained herein. The protonation of QCR at the carboxylic group instead of the quinoline structure was attributed to the weak electronegative property of nitrogen atom induced by the electron-withdrawing groups. It is anticipated that this work could not only help in gaining a deep insight into the acid dissociation of quinclorac but also offering the key information on its reaction and interaction with others.

  11. Experimental determination of spectral indices by scanning of fuel rod in the IPEN/MB-01 reactor

    International Nuclear Information System (INIS)

    Fanaro, Leda Cristina Cabelo Bernardes

    2009-01-01

    In this work, the spectral indexes 28ρ * and 25δ * , and gamma efficiency factor in the IPEN/MB-01 reactor were determined experimentally employing a rod scanning technique. In the case of 28ρ * , this method has the advantage of eliminating most of the correction factors derived from the calculations. Only the fission yield factor and the relative fission rate in the 235 U remain in the determination of the 25δ * . The experiments were performed with different thicknesses of cadmium sleeves: 0.55 mm, 1.10 mm and 2.20 mm. The final experimental uncertainty achieved in the experiment, less that 1 %, and the excellent geometrical and material data characterization of the IPEN/MB-01 reactor allow to use the results as benchmark for validate calculation methods and related nuclear data libraries. The comparison between calculated values and experimental values was performed by employing the MCNP-5 code and the nuclear data libraries: ENDF/B-VI.8, ENDF/B-VII.0, JENDL-3.3 and JEFF-3.1. The results demonstrate that the difference among libraries is very small. Also, the comparison between calculated values and experimental values shows that there has been considerable progress in the recent nuclear data libraries. The best result is obtained with ENDF/B-VII.0 nuclear data library, and the highest discrepancy was obtained with JEFF-3.1 and JENDL-3.3 nuclear data libraries. (author)

  12. Using UCODE_2005 and PHREEQC to determine thermodynamic constants from experimental data.

    Science.gov (United States)

    Skold, Magnus E; Thyne, Geoffrey D; McCray, John E

    2007-01-01

    This article presents a method for estimating chemical thermodynamic constants from experimental data using the two computer programs UCODE_2005 and PHREEQC. As an example, the conditional stability constant for lead (Pb) complexation by a remediation agent (carboxymethyl-beta-cyclodextrin) is estimated, but the method can be applied to estimate other thermodynamic parameters such as sorption constants and degradation rate constants. Advantages of this technique include estimation of uncertainties associated with estimated parameters, evaluation of information content of observations, statistical evaluation of the appropriateness of the conceptual model, and statistical-based comparison of different models.

  13. Direct Determination of Absolute Configuration of Methyl-Substituted Phenyloxiranes: A Combined Experimental and Theoretical Approach

    DEFF Research Database (Denmark)

    Fristrup, Peter; Lassen, Peter Rygaard; Johannessen, Christian

    2006-01-01

    obtained from quantum mechanical calculations (density functional theory with the B3LYP hybrid exchange correlation functional with 6-31++G**, aug-cc-pVDZ, or aug-cc-pVTZ basis set) and related to the physical structure of the compounds. The absolute configuration could be established directly in each case...... by comparing experimental and theoretical spectra. In addition, we have been able to document the changes that occur both in structures and in the VA and VCD spectra due to substituent effects on the oxirane ring....

  14. Experimental determination and prediction of liquid-solid equilibria for binary (methyl palimitate + naphthalene mixture

    Directory of Open Access Journals (Sweden)

    Benziane M.

    2013-07-01

    Full Text Available Solid-liquid equilibria for binary mixtures of {Methyl palmitate (1 + Naphthalene (2} were measured using differential scanning calorimeter (DSC. Simple eutectic behaviours for this system are observed. The experimental results were correlated by means of the NRTL, Wilson, UNIQUAC and ideal models. The root-mean-square deviations of the solubility temperatures for all measured data vary from 0.5477 K (for UNIQUAC model to 3.34K; the deviation depend on the model used. The best solubility correlation was obtained with UNIQUAC model and this observation confirms previous results.

  15. Analytical and experimental procedures for determining propagation characteristics of millimeter-wave gallium arsenide microstrip lines

    Science.gov (United States)

    Romanofsky, Robert R.

    1989-01-01

    In this report, a thorough analytical procedure is developed for evaluating the frequency-dependent loss characteristics and effective permittivity of microstrip lines. The technique is based on the measured reflection coefficient of microstrip resonator pairs. Experimental data, including quality factor Q, effective relative permittivity, and fringing for 50-omega lines on gallium arsenide (GaAs) from 26.5 to 40.0 GHz are presented. The effects of an imperfect open circuit, coupling losses, and loading of the resonant frequency are considered. A cosine-tapered ridge-guide text fixture is described. It was found to be well suited to the device characterization.

  16. Experimental determination and modelling of interface area concentration in horizontal stratified flow

    International Nuclear Information System (INIS)

    Junqua-Moullet, Alexandra

    2003-01-01

    This research thesis concerns the modelling and experimentation of biphasic liquid/gas flows (water/air) while using the two-fluid model, a six-equation model. The author first addresses the modelling of interfacial magnitudes for a known topology (problem of two-fluid model closure, closure relationships for some variables, equation for a given configuration). She reports the development of an equation system for interfacial magnitudes. The next parts deal with experiments and report the study of stratified flows in the THALC experiment, and more particularly the study of the interfacial area concentration and of the liquid velocities in such flows. Results are discussed, as well as their consistency

  17. Modal Analysis and Experimental Determination of Optimum Tool Shank Overhang of a Lathe Machine

    Directory of Open Access Journals (Sweden)

    Nabin SARDAR

    2008-12-01

    Full Text Available Vibration of Tool Shank of a cutting tool has large influence on tolerances and surface finish of products. Frequency and amplitude of vibrations depend on the overhang of the shank of the cutting tool. In turning operations, when the tool overhang is about 2 times of the tool height, the amplitude of the vibration is almost zero and dimensional tolerances and surface finish of the product becomes high. In this paper, the above statement is verified firstly by using a finite element analysis of the cutting tool with ANSYS software package and secondly, with experimental verification with a piezoelectric sensor.

  18. Marginal Space Deep Learning: Efficient Architecture for Volumetric Image Parsing.

    Science.gov (United States)

    Ghesu, Florin C; Krubasik, Edward; Georgescu, Bogdan; Singh, Vivek; Yefeng Zheng; Hornegger, Joachim; Comaniciu, Dorin

    2016-05-01

    Robust and fast solutions for anatomical object detection and segmentation support the entire clinical workflow from diagnosis, patient stratification, therapy planning, intervention and follow-up. Current state-of-the-art techniques for parsing volumetric medical image data are typically based on machine learning methods that exploit large annotated image databases. Two main challenges need to be addressed, these are the efficiency in scanning high-dimensional parametric spaces and the need for representative image features which require significant efforts of manual engineering. We propose a pipeline for object detection and segmentation in the context of volumetric image parsing, solving a two-step learning problem: anatomical pose estimation and boundary delineation. For this task we introduce Marginal Space Deep Learning (MSDL), a novel framework exploiting both the strengths of efficient object parametrization in hierarchical marginal spaces and the automated feature design of Deep Learning (DL) network architectures. In the 3D context, the application of deep learning systems is limited by the very high complexity of the parametrization. More specifically 9 parameters are necessary to describe a restricted affine transformation in 3D, resulting in a prohibitive amount of billions of scanning hypotheses. The mechanism of marginal space learning provides excellent run-time performance by learning classifiers in clustered, high-probability regions in spaces of gradually increasing dimensionality. To further increase computational efficiency and robustness, in our system we learn sparse adaptive data sampling patterns that automatically capture the structure of the input. Given the object localization, we propose a DL-based active shape model to estimate the non-rigid object boundary. Experimental results are presented on the aortic valve in ultrasound using an extensive dataset of 2891 volumes from 869 patients, showing significant improvements of up to 45

  19. Experimental Determination of Temperature During Rotary Friction Welding of AA1050 Aluminum with AISI 304 Stainless Steel

    Directory of Open Access Journals (Sweden)

    Eder Paduan Alves

    2012-03-01

    Full Text Available The purpose of this study was the temperature monitoring at bonding interface during the rotary friction welding process of dissimilar materials: AA1050 aluminum with AISI 304 stainless steel. As it is directly related to the mechanical strenght of the junction, its experimental determination in real time is of fundamental importance for understanding and characterizing the main process steps, and the definition and optimization of parameters. The temperature gradients were obtained using a system called Thermocouple Data-Logger, which allowed monitoring and recording data in real-time operation. In the graph temperature versus time obtained, the heating rates, cooling were analyzed, and the maximum temperature was determined that occurred during welding, and characterized every phases of the process. The efficiency of this system demonstrated by experimental tests and the knowledge of the temperature at the bonding interface open new lines of research to understand the process of friction welding.

  20. Volumetrically controlled ultrafiltration. Current experiences and future prospects.

    Science.gov (United States)

    Roy, T; Ahrenholz, P; Falkenhagen, D; Klinkmann, H

    1982-05-01

    Exact control of ultrafiltration (UF) is a prerequisite for high flux dialysis and hemodiafiltration. Volumetric dialysate balancing is the best current method for the use of dialyzers with high water permeabilities. The precision of UF control by volumetric dialysate balancing is in agreement with all medical requirements. A positive influence of volumetric UF control on patients undergoing chronic hemodialysis can be shown by the frequencies of dialysis side effects. Volumetric UF control is only a first step towards an intelligent UF module to correlate water removal, solute removal and sodium balance.

  1. Experimental determination of the frequency and field dependence of Specific Loss Power in Magnetic Fluid Hyperthermia

    Science.gov (United States)

    Cobianchi, M.; Guerrini, A.; Avolio, M.; Innocenti, C.; Corti, M.; Arosio, P.; Orsini, F.; Sangregorio, C.; Lascialfari, A.

    2017-12-01

    Magnetic nanoparticles are promising systems for biomedical applications and in particular for Magnetic Fluid Hyperthermia, a therapy that utilizes the heat released by such systems to damage tumor cells. We present an experimental study of the physical properties that influences the capability of heat release, i.e. the Specific Loss Power, SLP, of three biocompatible ferrofluid samples having a magnetic core of maghemite with different diameter d = 10.2, 14.6 and 19.7 nm. The SLP was measured as a function of frequency f and intensity H of the applied alternating magnetic field, and it turned out to depend on the core diameter, as expected. The results allowed us to highlight experimentally that the physical mechanism responsible for the heating is size-dependent and to establish, at applied constant frequency, the phenomenological functional relationship SLP = c·Hx, with 2 ≤ xmagnetic hyperthermia devices. For the smallest sample, the effective relaxation time τeff ≈ 19.5 ns obtained from SLP data is in agreement with the value estimated from magnetization data, thus confirming the validity of the Linear Response Theory model for this system at properly chosen field intensity and frequency.

  2. Does structural complexity determine the morphology of assemblages? An experimental test on three continents.

    Directory of Open Access Journals (Sweden)

    Heloise Gibb

    Full Text Available Understanding how species will respond to global change depends on our ability to distinguish generalities from idiosyncrasies. For diverse, but poorly known taxa, such as insects, species traits may provide a short-cut to predicting species turnover. We tested whether ant traits respond consistently to habitat complexity across geographically independent ant assemblages, using an experimental approach and baits. We repeated our study in six paired simple and complex habitats on three continents with distinct ant faunas. We also compared traits amongst ants with different foraging strategies. We hypothesised that ants would be larger, broader, have longer legs and more dorsally positioned eyes in simpler habitats. In agreement with predictions, ants had longer femurs and dorsally positioned eyes in simple habitats. This pattern was most pronounced for ants that discovered resources. Body size and pronotum width responded as predicted for experimental treatments, but were inconsistent across continents. Monopolising ants were smaller, with shorter femurs than those that occupied or discovered resources. Consistent responses for several traits suggest that many, but not all, aspects of morphology respond predictably to habitat complexity, and that foraging strategy is linked with morphology. Some traits thus have the potential to be used to predict the direction of species turnover, changes in foraging strategy and, potentially, evolution in response to changes in habitat structure.

  3. Dynamic strength and failure of 430F stainless steel determined by combined experimental-numerical method

    Science.gov (United States)

    Paris, Vitaly; Cohen, Amitay; Porat, Elkana; Fridman, Pinhas; Harpenes, Zvi; Yosef-Hai, Arnon; Levi-Hevroni, David

    2017-06-01

    Dynamic flow stress of metals is well known to depend significantly on the strain rate. Strain to failure behavior of ductile metals can be influenced by both the stress triaxiality and the strain rate. While either compressive or tensile Split Hopkinson Pressure Bar system (SHPB) are commonly used to obtain flow stress and failure data for metals, experimental methodologies to obtain such data under conditions of shear loading are less based. In the present study we have investigated the effect of strain rate on the flow stress and strain to failure of 430F stainless steel at strain rates ranging from 400 to 16000 1/sec using shear disc specimens (SDS) incorporated into standard SHPB system. The SDS sample is a disc having axisymmetric slits on its both flat faces which is sheared during the test by ring and cylinder-shaped adaptors mounted between the bars. The analysis of the data was performed by matching the experimental signals with results of numerical modeling of the tests. The obtained flow stress versus strain rate data were fitted with Cowper-Symonds model. The results indicate strong dependence of flow stress of 430F steel on strain rate in the investigated range of rates. The strain to failure data demonstrates a noticeable decrease with increase of the strain rate.

  4. Experimental determination of liquidus of Fe-Zr by spot technique

    International Nuclear Information System (INIS)

    Ramakrishna, P.; Samanta, B.; Balakrishnan, S.

    2016-01-01

    Metallic fuel alloy for fast reactor mainly consist of U-Pu-Zr housed in T91 clad. Study of thermophysical properties of fuel element and cladding material is vital for the fuel designer to optimize the design feature and predict the fuel behavior under reactor operating conditions.To understand the fuel-clad interaction the phase diagram study of Fe-Zr system is very important since future reactors use U-Pu-Zr alloy as fuel and stainless steel as clad. The eutectic temperature in Fe-Zr alloy system has been established experimentally by various methods. Information on the liquidus temperatures of Fe-Zr is scanty in the literature excepting a very few experimental measurements. Hence measurement of liquidus temperatures is very essential to establish the phase diagram. Present work concentrates more on the generation of liquidus data of Fe-Zr binary alloy system by Spot-technique. This is one among the advanced techniques for measuring the solid-liquid phase transition temperatures. (author)

  5. Equilibrium phase experimental determination of petroleum + gas systems at supercritical condition using ultrasonic technology; Estudo experimental do equilibrio de fases de sistemas de fracoes de petroleo e gases em condicoes supercriticas utilizando tecnicas de ultra-som: aparato experimental

    Energy Technology Data Exchange (ETDEWEB)

    Mehl, Ana; Pessoa, Fernando L.P.; Silva, Silvia M.C. da [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica; Feiteira, Jose F. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Escola de Engenharia

    2008-07-01

    In separation process of multicomponent systems based on phase equilibrium is essential know the phase behavior and the critical points of the system for determination and optimization of the operational conditions. The experimental apparatus presents the challenge of determine the equilibrium phase dates of a system composed by petroleum residua and supercritical solvent. The used method, named acoustic method, allows the composition identification of the phases in equilibrium also in cloudy systems as they are the systems formed by residues of crude oil. For this reason, the acoustic methodology, based on the ultra-sound technology will be used in the study of the phase equilibrium and experimental characterization of the system, in benches scale, operating in severe conditions of temperature and pressure.The acoustic method is one not invasive and not subjective technique, what becomes the work in high pressures safer. (author)

  6. Experimental Determination and Numerical Modelling of Process Induced Strains and Residual Stresses in Thick Glass/Epoxy Laminate

    DEFF Research Database (Denmark)

    Nielsen, Michael Wenani; Hattel, Jesper Henri; Løgstrup Andersen, Tom

    2012-01-01

    In this work, a cure hardening instantaneous linear elastic (CHILE) model and a path dependent (PD) constitutive approach are compared, for the case of modelling strain build-up during curing of a thick composite laminate part. The PD approach is a limiting case of viscoelasticity with path...... dependency on temperature and cure degree. Model predictions are compared to experimentally determined in-situ strains, determined using FBG sensors. It was found that both models offer good approximations of internal strain build-up. A general shortcoming is the lack of capturing rate-dependent effects...

  7. [Quantitative volumetric determinations on MR tomograms in communicating hydrocephalus].

    Science.gov (United States)

    Langkowski, J H; Palmié, S G; von Koschitzky, H; Imme, M; Maas, R; Schmidt, K H; Heller, M

    1989-02-01

    For patients with communicating hydrocephalus the implantation of a cardioventricular shunt is mostly an approved therapy. However, indications are frequently problematic and therefore a shunt operation will not be always successful. The proof of periventricular oedemas in addition to clinical signs seems to be a criterion for an indication for implantation and for the selection of a special valve. With the aid of a newly developed computer programme volume estimation of the ventricular system and the periventricular oedemas has been effected for six patients on T2-weighted MR-tomograms (1.5 tesla). Quotients of the different volumes are correlated with cerebrospinal fluid (CSF) pressure obtained during shunt implantation or lumbar measurement. Distinct indications have been found for a correlation between the volume of the periventricular oedemas and the pressure measurements.

  8. Volumetric MRI of the limbic system: anatomic determinants

    Energy Technology Data Exchange (ETDEWEB)

    Bilir, E.; Craven, W.; Hugg, J.; Gilliam, F.; Martin, R.; Faught, E.; Kuzniecky, R. [UAB Epilepsy Center, Department of Neurology, University of Alabama at Birmingham, Birmingham, AL (United States)

    1998-03-01

    The limbic system comprises the hippocampal formation, fornix, mamillary bodies, thalamus, and other integrated structures. It is involved in complex functions including memory and emotion and in diseases such as temporal lobe epilepsy. Volume measurements of the amygdala and hippocampus have been used reliably to study patients with temporal lobe epilepsy but have not extended to other limbic structures. We performed volume measurements of hippocampus, amygdala, fornix and mamillary bodies in healthy individuals. Measurements of the amygdala, hippocampus, fornix and mamillary bodies revealed significant differences in volume between right and left sides (P < 0.001). The intraclass coefficient of variation for measurements was high for all structures except the mamillary bodies. Qualitative image assessment of the same structures revealed no asymmetries between the hemispheres. This technique can be applied to the study of disorders affecting the limbic system. (orig.) With 4 figs., 2 tabs., 23 refs.

  9. Volumetric MRI of the limbic system: anatomic determinants

    International Nuclear Information System (INIS)

    Bilir, E.; Craven, W.; Hugg, J.; Gilliam, F.; Martin, R.; Faught, E.; Kuzniecky, R.

    1998-01-01

    The limbic system comprises the hippocampal formation, fornix, mamillary bodies, thalamus, and other integrated structures. It is involved in complex functions including memory and emotion and in diseases such as temporal lobe epilepsy. Volume measurements of the amygdala and hippocampus have been used reliably to study patients with temporal lobe epilepsy but have not extended to other limbic structures. We performed volume measurements of hippocampus, amygdala, fornix and mamillary bodies in healthy individuals. Measurements of the amygdala, hippocampus, fornix and mamillary bodies revealed significant differences in volume between right and left sides (P < 0.001). The intraclass coefficient of variation for measurements was high for all structures except the mamillary bodies. Qualitative image assessment of the same structures revealed no asymmetries between the hemispheres. This technique can be applied to the study of disorders affecting the limbic system. (orig.)

  10. Numerical and experimental determination of the minimum and maximum measuring times for the hot wire parallel technique

    Directory of Open Access Journals (Sweden)

    Santos W. N. dos

    2003-01-01

    Full Text Available The hot wire technique is considered to be an effective and accurate means of determining the thermal conductivity of ceramic materials. However, specifically for materials of high thermal diffusivity, the appropriate time interval to be considered in calculations is a decisive factor for getting accurate and consistent results. In this work, a numerical simulation model is proposed with the aim of determining the minimum and maximum measuring time for the hot wire parallel technique. The temperature profile generated by this model is in excellent agreement with that one experimentally obtained by this technique, where thermal conductivity, thermal diffusivity and specific heat are simultaneously determined from the same experimental temperature transient. Eighteen different specimens of refractory materials and polymers, with thermal diffusivities ranging from 1x10-7 to 70x10-7 m²/s, in shape of rectangular parallelepipeds, and with different dimensions were employed in the experimental programme. An empirical equation relating minimum and maximum measuring times and the thermal diffusivity of the sample is also obtained.

  11. A practical method to determine the effective resolution in incoherent experimental electron tomography.

    Science.gov (United States)

    Heidari Mezerji, Hamed; Van den Broek, Wouter; Bals, Sara

    2011-04-01

    It is not straightforward to determine resolution for a 3D reconstruction when performing an electron tomography experiment. Different contributions such as missing wedge and misalignment add up and often influence the final resolution in an anisotropic manner. The conventional resolution measures can not be used for all of the reconstruction techniques, especially for iterative techniques which are more commonly used for electron tomography in materials science. Here we define a quantitative resolution measure that determines the resolution in three orthogonal directions of the reconstruction. As an application we use this measure to determine the optimum number of simultaneous iterative reconstruction technique (SIRT) iterations to reconstruct the gold nanoparticles, based on a high angle annular dark field STEM (HAADF-STEM) tilt series. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Determination of J-R curve from only one experimental test on one sample

    International Nuclear Information System (INIS)

    Lebey, J.; Roche, R.L.

    1983-01-01

    Increasing attention has been given in fracture mechanics to the use of the J concept not only as a criterion of the onset of crack propagation, but also as an aid in the study of propagation stability. As a consequence, there is a need to determine the variation of J with crack extension, this being usually presented in curves known as J-R curves. Earlier methods for determining such curves used several specimens. The present paper describes a procedure avoiding any direct measurement of the crack length and giving a correct value of J when crack propagation occurs. (author)

  13. Experimental determination of the π meson structure functions by the Drell-Yan mechanism

    International Nuclear Information System (INIS)

    Badier, J.; Bourotte, J.; Mine, P.; Vanderhaghen, R.; Weisz, S.; Boucrot, J.; Callot, O.; Decamp, D.; Karyotakis, Y.; Lefrancois, J.; Crozon, M.; Delpierre, P.; Leray, T.; Maillard, J.; Tilquin, A.; Valentin, J.

    1983-01-01

    We have studied high statistics samples of dimuon events (proportional35,000) produced from πsup(+-) on platinum target in the mass interval 4.2 2 sigma/dx 1 dx 2 to π + and π - data. At 200 GeV, the simultaneous use of π + and π - data allows a separate determination of the valence and sea structure functions of the π. Furthermore, the 150 and 280 GeV data allow an accurate determination of the shape of the valence structure function and give an estimate of its evolution between Q 2 =25 and 50 GeV 2 . (orig.)

  14. Experimental determination of thermal conductivity of soil with a thermal response test

    OpenAIRE

    Banjac Miloš J.; Todorović Maja N.; Ristanović Milan R.; Galić Radoslav D.

    2012-01-01

    Optimal design of a borehole heat exchanger, as the outer part of a ground source heat pump heating system, requires information on the thermal properties of the soil. Those data, the effective thermal conductivity of the soil λeff and the average temperature of the soil T0, enable us to determine the necessary number and depth of boreholes. The determination of thermal conductivity of the soil in laboratory experiments does not usually coincide with the data under in-situ conditions. T...

  15. EXPERIMENTAL DETERMINATION OF WHISTLER WAVE DISPERSION RELATION IN THE SOLAR WIND

    Energy Technology Data Exchange (ETDEWEB)

    Stansby, D.; Horbury, T. S.; Chen, C. H. K.; Matteini, L., E-mail: david.stansby14@imperial.ac.uk [Department of Physics, Imperial College London, London SW7 2AZ (United Kingdom)

    2016-09-20

    The origins and properties of large-amplitude whistler wavepackets in the solar wind are still unclear. In this Letter, we utilize single spacecraft electric and magnetic field waveform measurements from the ARTEMIS mission to calculate the plasma frame frequency and wavevector of individual wavepackets over multiple intervals. This allows direct comparison of experimental measurements with theoretical dispersion relations to identify the observed waves as whistler waves. The whistlers are right-hand circularly polarized, travel anti-sunward, and are aligned with the background magnetic field. Their dispersion is strongly affected by the local electron parallel beta in agreement with linear theory. The properties measured are consistent with the electron heat flux instability acting in the solar wind to generate these waves.

  16. Real life experimental determination of platinum group metals content in automotive catalytic converters

    Science.gov (United States)

    Yakoumis, I.; Moschovi, A. M.; Giannopoulou, I.; Panias, D.

    2018-03-01

    The real life experimental protocol for the preparation of spent automobile catalyst samples for elemental analysis is thoroughly described in the following study. Collection, sorting and dismantling, homogenization and sample preparation for X-Ray fluorescence spectroscopy and Atomic Adsorption Spectroscopy combined with Inductive coupled plasma mass spectrometry are discussed in detail for both ceramic and metallic spent catalysts. The concentrations of Platinum Group Metals (PGMs) in spent catalytic converters are presented based on typical consignments of recycled converters (more than 45,000 pieces) from the Greek Market. The conclusions clearly denoted commercial metallic catalytic foil contains higher PGMs loading than ceramic honeycombs. On the other hand, the total PGMs loading in spent ceramic catalytic converters has been found higher than the corresponding value for the metallic ones.

  17. Experimental determination of the impact of polysilicon LER on sub-100-nm transistor performance

    Science.gov (United States)

    Patterson, Kyle; Sturtevant, John L.; Alvis, John R.; Benavides, Nancy; Bonser, Douglas; Cave, Nigel; Nelson-Thomas, Carla; Taylor, William D.; Turnquest, Karen L.

    2001-08-01

    Photoresist line edge roughness (LER) has long been feared as a potential limitation to the application of various patterning technologies to actual devices. While this concern seems reasonable, experimental verification has proved elusive and thus LER specifications are typically without solid parametric rationale. We report here the transistor device performance impact of deliberate variations of polysilicon gate LER. LER magnitude was attenuated by more than a factor of 5 by altering the photoresist type and thickness, substrate reflectivity, masking approach, and etch process. The polysilicon gate LER for nominally 70 - 150 nm devices was quantified using digital image processing of SEM images, and compared to gate leakage and drive current for variable length and width transistors. With such comparisons, realistic LER specifications can be made for a given transistor. It was found that subtle cosmetic LER differences are often not discernable electrically, thus providing hope that LER will not limit transistor performance as the industry migrates to sub-100 nm patterning.

  18. Reciprocity-based experimental determination of dynamic forces and moments: A feasibility study

    Science.gov (United States)

    Ver, Istvan L.; Howe, Michael S.

    1994-01-01

    BBN Systems and Technologies has been tasked by the Georgia Tech Research Center to carry Task Assignment No. 7 for the NASA Langley Research Center to explore the feasibility of 'In-Situ Experimental Evaluation of the Source Strength of Complex Vibration Sources Utilizing Reciprocity.' The task was carried out under NASA Contract No. NAS1-19061. In flight it is not feasible to connect the vibration sources to their mounting points on the fuselage through force gauges to measure dynamic forces and moments directly. However, it is possible to measure the interior sound field or vibration response caused by these structureborne sound sources at many locations and invoke principle of reciprocity to predict the dynamic forces and moments. The work carried out in the framework of Task 7 was directed to explore the feasibility of reciprocity-based measurements of vibration forces and moments.

  19. Experimental Determinations on Kinematics of a Translational Joint of an Industrial Robot

    Directory of Open Access Journals (Sweden)

    Calin-Octavian Miclosina

    2017-11-01

    Full Text Available The paper presents a 6-DOF industrial robot and the driving system of its base translational joint. By imposing certain positions of the translational joint and determining the durations in which these positions are reached, average speed is computed. The paper shows how the clearances influence the average speed, depending on the displacement value.

  20. Determination of the Molar Volume of Hydrogen from the Metal-Acid Reaction: An Experimental Alternative.

    Science.gov (United States)

    de Berg, Kevin; Chapman, Ken

    1996-01-01

    Describes an alternative technique for determining the molar volume of hydrogen from the metal-acid reaction in which the metal sample is encased in a specially prepared cage and a pipette filler is used to fill an inverted burette with water. Eliminates some difficulties encountered with the conventional technique. (JRH)

  1. Cellular uptake of nanoparticles as determined by particle properties, experimental conditions, and cell type

    NARCIS (Netherlands)

    Kettler, Katja; Veltman, Karin; van de Meent, Dik; van Wezel, Annemarie|info:eu-repo/dai/nl/141376074; Hendriks, A. Jan

    2014-01-01

    The increased application of nanoparticles (NPs) is increasing the risk of their release into the environment. Although many toxicity studies have been conducted, the environmental risk is difficult to estimate, because uptake mechanisms are often not determined in toxicity studies. In the present

  2. Determination of ion mobilities of radionuclides in a free electrolyte. Methods and experimental organization

    International Nuclear Information System (INIS)

    Milanov, M.; Doberenz, W.; Marinov, A.; Khalkin, V.A.

    1983-01-01

    A new variant of technique for determining ion mobilities by means of horizontal zone electrophoresis in free solutions is developed. Setup circuit is presented. Some details of experiment and results of measuring limiting mobilities of 131 I - and 160 Tb 3+ are given. On these examples the method reproducibility was checked

  3. Experimental determination of the gravitational forces at separations around 10 meters

    International Nuclear Information System (INIS)

    Yu, H.; Ni, W.; Hu, C.; Liu, F.; Yang, C.; Liu, W.

    1979-01-01

    We use a Worden gravimeter to measure the gravitational forces at fixed positions when a large oil tank is full and when it is empty. The differences determine the gravitational constant at various separations around 10 m to about 10% accuracy

  4. Development and experimental validation of a tool to determine out-of-field dose in radiotherapy

    International Nuclear Information System (INIS)

    Bessieres, I.

    2013-01-01

    Over the last two decades, many technical developments have been achieved on intensity modulated radiotherapy (IMRT) and allow a better conformation of the dose to the tumor and consequently increase the success of cancer treatments. These techniques often reduce the dose to organs at risk close to the target volume; nevertheless they increase peripheral dose levels. In this situation, the rising of the survival rate also increases the probability of secondary effects expression caused by peripheral dose deposition (second cancers for instance). Nowadays, the peripheral dose is not taken into account during the treatment planning and no reliable prediction tool exists. However it becomes crucial to consider the peripheral dose during the planning, especially for pediatric cases. Many steps of the development of an accurate and fast Monte Carlo out-of-field dose prediction tool based on the PENELOPE code have been achieved during this PhD work. To this end, we demonstrated the ability of the PENELOPE code to estimate the peripheral dose by comparing its results with reference measurements performed on two experimental configurations (metrological and pre-clinical). During this experimental work, we defined a protocol for low doses measurement with OSL dosimeters. In parallel, we highlighted the slow convergence of the code for clinical use. Consequently, we accelerated the code by implementing a new variance reduction technique called pseudo-deterministic transport which is specifically with the objective of improving calculations in areas far away from the beam. This step improved the efficiency of the peripheral doses estimation in both validation configurations (by a factor of 20) in order to reach reasonable computing times for clinical application. Optimization works must be realized in order improve the convergence of our tool and consider a final clinical use. (author) [fr

  5. Determination of the molecular signature of fossil conifers by experimental palaeochemotaxonomy - Part 1: The Araucariaceae family

    Science.gov (United States)

    Lu, Y.; Hautevelle, Y.; Michels, R.

    2012-08-01

    Several extant species of the Araucariaceae family (one of the families of conifers) were invested for the experimental artificial maturation by confined pyrolysis, in order to realize the transformation of biomolecules to geomolecules in laboratory conditions. The experimental study of diagenetized molecular signatures of the Araucariaceae species (common, inter- and infra-generic characteristics) allow to complete our knowledge in botanical palaeochemotaxonomy. Such knowledge is relevant to the reconstitution of palaeoflora and palaeoclimatic reconstruction, archaeology and environmental studies. In this work, major carbon skeleton types of Araucariaceae are detected in the organic solvent extracts of fresh and pyrolyzed plants using gas chromatography-mass spectrometry. The results show that all species of Araucariaceae are firstly characterized by a predominance of saturated tetracyclic diterpenoids. Moreover, the Araucaria genus shows a high relative abundance of bicyclic sesquiterpenoids, particularly compounds of the cadalane-type compounds accompanied by those of eudesmane-type, bisabolane-type as well as chamazulene, pentamethyl-dihydroindenes. Diterpenoids are of the labdane-type, isopimarane, abietane-type (essentially derived from abietanoic acids) as well as isohexyl alkylaromatic hydrocarbons. Compared to the tetracyclic diterpenoids, these compounds show a relatively lower abundance, reaching trace levels in the case of saturated abietanes. Distribution of sesqui- and diterpenoids of Agathis shows some similarities to that of Araucaria, with the exception of one species, in which the tetracyclic compounds are absent and the abietane-type (essentially derived from abietanoic acids) predominant. High similarities between the Wollemia and Araucaria genera are observed. Both are characterized by some high relative abundance of tetracyclic compounds with no predominance of other specific diterpenoids.

  6. Experimental and numerical determination of the mechanical response of teeth with reinforced posts

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulos, Triantafillos; Papadogiannis, Dimitris [Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens (Greece); Mouzakis, Dionysios E [Department of Mechanical Engineering, ATEI of Larisa (Greece); Giannadakis, Konstantinos; Papanicolaou, George, E-mail: trpapad@dent.uoa.g [Composite Materials Group, Department of Mechanical Engineering and Aeronautics, University of Patras (Greece)

    2010-06-01

    The aim of this study was to evaluate the mechanical behavior of endodontically treated teeth restored with fiber reinforced composite posts versus titanium posts, by both experimental testing and numerical simulation (finite element analysis (FEA)). Forty maxillary central incisors were endodontically treated to a size 45 file and then obturated using gutta-percha points and sealer with the lateral condensation technique. The teeth were divided into four groups of ten teeth each. All the posts were of similar dimensions. The first group was restored using carbon fiber reinforced posts (CB), the second and third groups were restored using glass fiber reinforced posts (DP and FW, respectively), and the fourth group (control group) was restored using conventional titanium posts (PP). Half of the specimens of every group were submitted to hydrothermal cycling (2000 cycles, at 5 {sup 0}C and 55 {sup 0}C, respectively). All specimens were loaded until failure at a 45{sup 0} angle with respect to the longitudinal axis at a crosshead speed of 0.5 mm min{sup -1}. A two-dimensional finite element model was designed in order to simulate the experimentally obtained results. Mechanical testing revealed that teeth restored with titanium posts exhibited the highest fracture strength. Debonding of the core was the main failure mode observed in glass fiber posts, whereas vertical root fractures were observed in the titanium posts. FEA revealed that the maximum stresses were developed at the interface between the post, dentin and the composite core critical regions in all three cases. Hydrothermal cycling had no significant effect on the fracture behavior of fiber reinforced composite posts.

  7. Assessing vertebral fracture risk on volumetric quantitative computed tomography by geometric characterization of trabecular bone structure

    Science.gov (United States)

    Checefsky, Walter A.; Abidin, Anas Z.; Nagarajan, Mahesh B.; Bauer, Jan S.; Baum, Thomas; Wismüller, Axel

    2016-03-01

    The current clinical standard for measuring Bone Mineral Density (BMD) is dual X-ray absorptiometry, however more recently BMD derived from volumetric quantitative computed tomography has been shown to demonstrate a high association with spinal fracture susceptibility. In this study, we propose a method of fracture risk assessment using structural properties of trabecular bone in spinal vertebrae. Experimental data was acquired via axial multi-detector CT (MDCT) from 12 spinal vertebrae specimens using a whole-body 256-row CT scanner with a dedicated calibration phantom. Common image processing methods were used to annotate the trabecular compartment in the vertebral slices creating a circular region of interest (ROI) that excluded cortical bone for each slice. The pixels inside the ROI were converted to values indicative of BMD. High dimensional geometrical features were derived using the scaling index method (SIM) at different radii and scaling factors (SF). The mean BMD values within the ROI were then extracted and used in conjunction with a support vector machine to predict the failure load of the specimens. Prediction performance was measured using the root-mean-square error (RMSE) metric and determined that SIM combined with mean BMD features (RMSE = 0.82 +/- 0.37) outperformed MDCT-measured mean BMD (RMSE = 1.11 +/- 0.33) (p < 10-4). These results demonstrate that biomechanical strength prediction in vertebrae can be significantly improved through the use of SIM-derived texture features from trabecular bone.

  8. Modification of surface layers of copper under the action of the volumetric discharge initiated by an avalanche electron beam in nitrogen and CO2 at atmospheric pressure

    Science.gov (United States)

    Shulepov, M. A.; Akhmadeev, Yu. Kh.; Tarasenko, V. F.; Kolubaeva, Yu. A.; Krysina, O. V.; Kostyrya, I. D.

    2011-05-01

    The results of experimental investigations of the action of the volumetric discharge initiated by an avalanche electron beam on the surface of copper specimens are presented. The volumetric (diffuse) discharge in nitrogen and CO2 at atmospheric pressure was initiated by applying high voltage pulses of nanosecond duration to a tubular foil cathode. It has been found that the treatment of a copper surface by this type of discharge increases the hardness of the surface layer due to oxidation.

  9. Experimental determination of the absorption rate of unattached radon progeny from respiratory tract to blood

    International Nuclear Information System (INIS)

    Butterweck, G.; Schuler, Ch.; Vessl, G.; Mueller, R.; Marsh, J.W.; Thrift, S.; Birchall, A.

    2002-01-01

    An exposure methodology was developed for the determination of the absorption rate of unattached radon progeny deposited in the human respiratory tract to blood. Twenty-one volunteers were exposed in a radon chamber during well-controlled aerosol and radon progeny conditions, with predominantly unattached radon daughters. Special efforts were made to restrict the dose to the volunteers to an absolute maximum of 0.08 mSv. Measurements of radon gas and radon progeny in blood samples of these volunteers indicated absorption half times of 20 min to 60 min. Former determinations, mainly performed with much larger aerosol particles of diameters between 100 nm and 1000 nm, implied absorption half times around 10 h. This indicates that the absorption of radon decay products from ciliated airways into blood is dependent upon particle size and particle composition. (author)

  10. Determination of critical micelle concentration of cetyltrimethylammonium bromide: Different procedures for analysis of experimental data

    Directory of Open Access Journals (Sweden)

    Goronja Jelena M.

    2016-01-01

    Full Text Available Conductivity of two micellar systems was measured in order to determine critical micelle concentration (CMC of cetyltrimethylammonium bromide (CTAB. Those systems were: CTin water and CTin binary mixture acetonitrile (ACN-water. Conductivity (κ-concentration (c data were treated by four different methods: conventional method, differential methods (first and second derivative and method of integration (methods A-D, respectively. As CTin water micellar system shows a sharp transition between premicellar and postmicellar part of the κ/c curve, any of the applied methods gives reliable CMC values and there is no statistically significant difference between them. However, for CTin ACN-water mixture micellar system the integration method for CMC determination is recommended due to a weak curvature of κ/c plot.

  11. Experimental determination of the antineutrino spectrum of the fission products of 238U

    International Nuclear Information System (INIS)

    Haag, Nils-Holger

    2013-01-01

    Fission of 238 U contributes about 10 % to the antineutrino emission of a pressurized water reactor. In the present thesis, the beta spectrum of the fission products of 238 U was determined in an experiment at the neutron source FRM II. This beta spectrum was subsequently converted into an antineutrino spectrum. This first measurement of the antineutrino spectrum supports all current and future reactor antineutrino experiments.

  12. Experimental determination of the antineutrino spectrum of the fission products of {sup 238}U

    Energy Technology Data Exchange (ETDEWEB)

    Haag, Nils-Holger

    2013-10-09

    Fission of {sup 238}U contributes about 10 % to the antineutrino emission of a pressurized water reactor. In the present thesis, the beta spectrum of the fission products of {sup 238}U was determined in an experiment at the neutron source FRM II. This beta spectrum was subsequently converted into an antineutrino spectrum. This first measurement of the antineutrino spectrum supports all current and future reactor antineutrino experiments.

  13. Experimental determination of harmonic conditions amplification in a distribution network by capacitor bank switching

    DEFF Research Database (Denmark)

    Baloi, Alexandru; Kocewiak, Lukasz Hubert; Bak, Claus Leth

    2012-01-01

    The paper presents a study comprising laboratory measurements for the evaluation of the harmonic amplification due to capacitor bank switching. The mathematical model of the amplification factors of the current flowing on the circuit elements is presented. Theoretical aspects, regarding the total...... is the harmonic impedance, “seen” in the bus of the capacitor bank switching. MatLab Simulink is used for the determination of the harmonic impedance....

  14. A quasi-experimental approach to determining success criteria for ICT projects

    OpenAIRE

    MILIS, Koen; Meulder, M.; MERCKEN, Roger

    2003-01-01

    Since the 1960's many authors accepted the triple constraints (time, cost, specification) as a standard measure of success and this still appears to be extremely important in evaluating the success of ICT projects. However, a project cannot always be seen as a complete success or a complete failure. Moreover, the parties involved may perceive the terms "success" or "failure" differently. The authors have set up a quasiexperiment (gaming) in order to determine the criteria used by the differen...

  15. Experimental determination of solubility parameters of oils as a function of pressure

    DEFF Research Database (Denmark)

    Verdier, Sylvain Charles Roland; Duong, Diep; Andersen, Simon Ivar

    2005-01-01

    (calculated from density measurements). This method was tested on seven pure compounds, and the deviation with literature data is solubility......In this work, the solubility parameter of dead and live crude oils was measured at 303.15 K and up to 300 bar, using the internal pressure approach. An indirect technique was chosen, using thermal expansivities (determined from microcalorimetric measurements) and isothermal compressibilities...

  16. Experimental Determination of Thermal Condutivity of Various Milk and Vegetable Oil Products

    OpenAIRE

    ÖZKAL, Sami Gökhan; TÜLEK, Yahya

    2014-01-01

    Thermal conductivity values of various milk and vegetable oil products were determined over a temperature range of 25o-75oC. Thermal conductivity of milk samples having higher solid content were found to be less than those having lower solid content. Thermal conductivity values of milk samples increased with increasing temperature. Thermal conductivity of oil samples was found to be similar and not to change with the increasing temperature. Also, mathematical models for the pre...

  17. Experimental determination of damping factors for walls of masonry and reinforced concrete

    International Nuclear Information System (INIS)

    Buttman, P.

    1983-01-01

    'Damping' is a fundamental parameter for the determination of the internal force with a given acceleration response spectrum when designing and dimensioning masonry and reinforced concrete walls for the loading case earthquake. The actual dampings of masonry and reinforced concrete walls are determined on a scale of 1:1 by means of a horizontal excitation at a chosen test setup. The test specimen have the dimensions b/h/d=100/200/11,5 cm and 24 cm. The horizontal and sinusoidal excitation of the test specimen is effected by a dynamic oscillating excitation with a maximum power of 20 kN. The evaluation of the measurements shows that the assumed damping values of 4% for the operating basis earthquake are realistic. In case of amplitudes corresponding to the loadings of the safe shutdown earthquake, however, dampings of 11% for reinforced concrete walls and of 24% for masonry walls were determined. This real damping behavior of reinforced concrete and masonry walls was documented by means of measurements, films and pictures. (orig.)

  18. Experimentally Determined Overall Heat Transfer Coefficients for Spacesuit Liquid Cooled Garments

    Science.gov (United States)

    Bue, Grant; Rhodes, Richard; Anchondo, Ian; Westheimer, David; Campbell, Colin; Vogel, Matt; Vonaue, Walt; Conger, Bruce; Stein, James

    2015-01-01

    A Human-In-The-Loop (HITL) Portable Life Support System 2.0 (PLSS 2.0) test has been conducted at NASA Johnson Space Center in the PLSS Development Laboratory from October 27, 2014 to December 19, 2014. These closed-loop tests of the PLSS 2.0 system integrated with human subjects in the Mark III Suit at 3.7 psi to 4.3 psi above ambient pressure performing treadmill exercise at various metabolic rates from standing rest to 3000 BTU/hr (880 W). The bulk of the PLSS 2.0 was at ambient pressure but effluent water vapor from the Spacesuit Water Membrane Evaporator (SWME) and the Auxiliary Membrane Evaporator (Mini-ME), and effluent carbon dioxide from the Rapid Cycle Amine (RCA) were ported to vacuum to test performance of these components in flight-like conditions. One of the objectives of this test was to determine the overall heat transfer coefficient (UA) of the Liquid Cooling Garment (LCG). The UA, an important factor for modeling the heat rejection of an LCG, was determined in a variety of conditions by varying inlet water temperature, flow rate, and metabolic rate. Three LCG configurations were tested: the Extravehicular Mobility Unit (EMU) LCG, the Oceaneering Space Systems (OSS) LCG, and the OSS auxiliary LCG. Other factors influencing accurate UA determination, such as overall heat balance, LCG fit, and the skin temperature measurement, will also be discussed.

  19. Experimental Research on the Determination of the Coefficient of Sliding Wear under Iron Ore Handling Conditions

    Directory of Open Access Journals (Sweden)

    G. Chen

    2017-09-01

    Full Text Available The handling of iron ore bulk solids maintains an increasing trend due to economic development. Because iron ore particles have hard composites and irregular shapes, the bulk solids handling equipment surface can suffer from severe sliding wear. Prediction of equipment surface wear volume is beneficial to the efficient maintenance of worn areas. Archard’s equation provides a theoretical solution to predict wear volume. To use Archard’s equation, the coefficient of sliding wear must be determined. To our best knowledge, the coefficient of sliding wear for iron ore handling conditions has not yet been determined. In this research, using a pin-on-disk tribometer, the coefficients of sliding wear for both Sishen particles and mild steel are determined with regard to iron ore handling conditions. Both naturally irregular and spherical shapes of particles are used to estimate average values of wear rate. Moreover, the hardness and inner structures of Sishen particles are examined, which adds the evidence of the interpretation of wear results. It is concluded that the coefficients of sliding wear can vary largely for both Sishen particle and mild steel. The wear rate decreases from transient- to steady-state. The average coefficient of sliding wear is capable of predicting wear with respect to long distances at the steady-state. Two types of sliding friction are distinguished. In addition, it is found that the temperature rise of the friction pairs has negligible influence on wear rate.

  20. Experimental and theoretical aspects of ab initio structure determination using powder diffraction techniques

    International Nuclear Information System (INIS)

    David, W.I.F.; Johnson, M.W.; Wilson, C.C.

    1988-01-01

    Neutron powder diffraction has, over the past two decades, developed into a powerful technique for the refinement of moderately complex crystal structures. The advent of a new generation of ultra-high resolution X-ray and neutron powder diffractometers, however, not only permits the refinement of more complex materials but also opens up new areas of research. Perhaps the most exciting development in powder diffraction techniques associated with high resolution is the ab initio determination of crystal structures. This has until recently been possible, in a routine way, only by single crystal studies. The compression of three dimensions of diffraction data to the one dimension of a powder diffraction pattern leads to an unavoidable loss of information. For many, but not all, crystal symmetries high resolution minimises this loss thus allowing the intensities of a sufficient number of resolved Bragg reflections from moderately complex materials to be extracted for use in structure solution by direct methods of phase determination and by Patterson methods. Recent structure determination using the high resolution powder diffractometer, HRPD, at ISIS will be presented. The inherent limitations resulting from crystal and instrumental resolution are discussed along with maximum entropy techniques that seek to optimise the information content of a powder diffraction pattern. (author) 36 refs., 1 fig., 3 tabs

  1. Experimental determination of nuclear reaction rates (n,γ) by the gamma-rays capture spectrometry technique

    International Nuclear Information System (INIS)

    Lucatero, M.A.

    1976-01-01

    The technique of the gamma-rays capture spectrometry was used in the experimental determination of nuclear reaction rates of the type (n,γ). This technique consists in the incidence of a thermal neutrons collimated beam upon a sample, detecting the capture spectrum of gamma rays emitted at a solid fixed angle. In the determination of the efficiency curve intrinsic to the detection electronic system the reactions 199 Hg(n,γ) 200 Hg, 56 Fe(n,γ) 57 Fe and 63 Cu(n,γ) 64 Cu were used with the energy of the gamma rays capture of 5.976, 7.635 and 7.915 Mev respectively, through the irradiation of standard samples of Hg(175.3g), Fe(110.4g) and Cu(108.5g) of cylindrical geometry the two former and parallelepiped the latter. The problem concerning the corrections due to the thermal neutrons flux depression, the gammas auto-attenuation, and the geometric factor due to the cylindrical and parallelepiped geometry are involved in the data process. The experimental determination of the reaction 35 Cl(n,γ) 36 Cl rate was made through the observation of the gamma caputre of 6.111 Mev when a sample of CaCl 2 of cylindrical geometry was irradiated. This rate can be favorably compared with the reaction rate determined theoretically. (author)

  2. Calculation of the weighting function and determination of the depth of correlation in micro-PIV from experimental particle images

    International Nuclear Information System (INIS)

    Hein, M; Seemann, R; Wieneke, B

    2014-01-01

    Micro-particle image velocimetry (µPIV) uses volume-illumination and imaging of particles through a single microscope objective. Displacement fields are obtained by image correlation and depend on all imaged particles, including defocused particles. The measured in-plane displacement is a weighted spatial average of the true displacement, with a weighting function W(z) that depends on the optical system and flow-gradients. The characteristic width of the weighting function W(z) is also referred to as depth of correlation (DOC) and is a measure up to which distance from the focal plane particles influence the measurement, which is crucial for the interpretation of measured flow fields. We present procedures to determine the W(z) from which the DOC can be derived and to directly determine the DOC from PIV double images, generated from experimentally recorded particle images. Both procedures provide comparable DOC results. Our approach allows determination of the DOC and W(z)as a function of out of plane gradients, optical setup parameters and PIV-analysis parameters. Experimental results for different objectives and particle sizes are discussed, revealing substantial deviations from theoretical predictions for high NA air-objectives. Moreover, using the determined weighting function W(z), the correction of measured flow profiles for errors introduced by the spatial averaging is demonstrated. (paper)

  3. The bearing capacity experimental determination of the keyed joints models in the transport construction

    Directory of Open Access Journals (Sweden)

    Dovzhenko Oksana

    2017-01-01

    Full Text Available The joints ensure the joint performance of the load carrying structural systems and they are the most responsible and important elements. Keyed joints are widely used in construction. They are characterized by an increased resistance to shear. On these grounds the structural concepts of keyed joints need further improvement. The article presents the research results of experimental test pieces five series in the form of single keys and one-keyed joints. Those samples have been tested in Poltava National Technical Yuriy Kondratyuk University. Follow strength factors have been varied: geometric parameters of joints (depth, height, width and their ratio; angle of support surface (rectangular, trapezoidal and triangular key; level of compression; reinforcement (quality of reinforcement and the nature of its location; jointing width. The samples were made of heavy-weight, expanded clay and fibre concrete. The experiments program includes influence study both of one of these factors and their combinations. The deformations, nature of failure, the ultimate load have been studied. Structural parameters of keyed joints which ensure the efficient behaviour have been installed.

  4. Determination of barium in surface and ground waters at Centro Experimental Aramar area

    International Nuclear Information System (INIS)

    Matoso, Erika; Cadore, Solange

    2015-01-01

    Barium can be found in waters up to 1 mg L -1 and came from natural sources such as sedimentary rocks erosion rich in feldspar and barite. Also anthropogenic activities can release this element such as oil and gas industry, agricultural defensives, chemical industry and waste disposal. At high doses, barium can be harmful to human central nervous system and can also cause high blood pressure, heart problems, fatigue and anxiety. The water potability defined by Brazilian's Ministry of Healthy sets barium concentration up to 0.7 mg L -1 and official regulation defines the same limit of this element to superficial waters (according CONAMA resolution 357/2005) and ground waters (Sao Paulo state regulation). In this work, barium was analyzed monthly in superficial waters from 4 different sampling locations, located in a ratio of 10-km-long from Centro Experimental Aramar (CEA) at Ipanema River, during one year, in order to evaluate the river in different conditions (seasons, temperature and rain period). The ground water was collected every six months. The analytical technique applied was ICP OES and the method conditions were optimized: wavelength, linearity, signal background ratio, detection and quantification limits. Data obtained in this work will contribute to evaluate the presence of barium at CEA region and nearby in order to compare it with current Brazilian regulations. (author)

  5. Experimental determination of thermal turbulence effects on a propagating laser beam

    Science.gov (United States)

    Ndlovu, Sphumelele C.; Chetty, Naven

    2015-08-01

    The effect of turbulence on propagating laser beams has been a subject of interest since the evolution of lasers back in 1959. In this work, an inexpensive and reliable technique for producing interferograms using a point diffraction interferometer (PDI) was considered to experimentally study the turbulence effects on a laser beam propagating through air. The formed interferograms from a propagating beamwere observed and digitally processed to study the strength of atmospheric turbulence. This technique was found to be sensitive enough to detect changes in applied temperature with distance between the simulated turbulence and laser path. These preliminary findings indicated that we can use a PDI method to detect and localise atmospheric turbulence parameters. Such parameters are very important for use in the military (defence laser weapons) and this is vital for South Africa (SA) since it has natural resources, is involved in peace keeping and mediation for other countries, and hence must have a strong defence system that will be able to locate, detect and destroy incoming missiles and other threatening atmospheric systems in order to protect its environment and avoid the initiation of countermeasures on its land.

  6. Experimental determination of the energy difference between competing isomers of deposited, size-selected gold nanoclusters.

    Science.gov (United States)

    Foster, D M; Ferrando, R; Palmer, R E

    2018-04-03

    The equilibrium structures and dynamics of a nanoscale system are regulated by a complex potential energy surface (PES). This is a key target of theoretical calculations but experimentally elusive. We report the measurement of a key PES parameter for a model nanosystem: size-selected Au nanoclusters, soft-landed on amorphous silicon nitride supports. We obtain the energy difference between the most abundant structural isomers of magic number Au 561 clusters, the decahedron and face-centred-cubic (fcc) structures, from the equilibrium proportions of the isomers. These are measured by atomic-resolution scanning transmission electron microscopy, with an ultra-stable heating stage, as a function of temperature (125-500 °C). At lower temperatures (20-125 °C) the behaviour is kinetic, exhibiting down conversion of metastable decahedra into fcc structures; the higher state is repopulated at higher temperatures in equilibrium. We find the decahedron is 0.040 ± 0.020 eV higher in energy than the fcc isomer, providing a benchmark for the theoretical treatment of nanoparticles.

  7. CLIPZ: a database and analysis environment for experimentally determined binding sites of RNA-binding proteins.

    Science.gov (United States)

    Khorshid, Mohsen; Rodak, Christoph; Zavolan, Mihaela

    2011-01-01

    The stability, localization and translation rate of mRNAs are regulated by a multitude of RNA-binding proteins (RBPs) that find their targets directly or with the help of guide RNAs. Among the experimental methods for mapping RBP binding sites, cross-linking and immunoprecipitation (CLIP) coupled with deep sequencing provides transcriptome-wide coverage as well as high resolution. However, partly due to their vast volume, the data that were so far generated in CLIP experiments have not been put in a form that enables fast and interactive exploration of binding sites. To address this need, we have developed the CLIPZ database and analysis environment. Binding site data for RBPs such as Argonaute 1-4, Insulin-like growth factor II mRNA-binding protein 1-3, TNRC6 proteins A-C, Pumilio 2, Quaking and Polypyrimidine tract binding protein can be visualized at the level of the genome and of individual transcripts. Individual users can upload their own sequence data sets while being able to limit the access to these data to specific users, and analyses of the public and private data sets can be performed interactively. CLIPZ, available at http://www.clipz.unibas.ch, aims to provide an open access repository of information for post-transcriptional regulatory elements.

  8. Determination of barium in surface and ground waters at Centro Experimental Aramar area

    Energy Technology Data Exchange (ETDEWEB)

    Matoso, Erika, E-mail: ematoso@hotmail.com [Centro Tecnologico da Marinha em Sao Paulo (CEA/CTMS), Ipero, SP (Brazil). Centro Experimental Aramar; Cadore, Solange, E-mail: cadore@iqm.unicamp.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Quimica. Departamento de Quimica Analica

    2015-07-01

    Barium can be found in waters up to 1 mg L{sup -1} and came from natural sources such as sedimentary rocks erosion rich in feldspar and barite. Also anthropogenic activities can release this element such as oil and gas industry, agricultural defensives, chemical industry and waste disposal. At high doses, barium can be harmful to human central nervous system and can also cause high blood pressure, heart problems, fatigue and anxiety. The water potability defined by Brazilian's Ministry of Healthy sets barium concentration up to 0.7 mg L{sup -1} and official regulation defines the same limit of this element to superficial waters (according CONAMA resolution 357/2005) and ground waters (Sao Paulo state regulation). In this work, barium was analyzed monthly in superficial waters from 4 different sampling locations, located in a ratio of 10-km-long from Centro Experimental Aramar (CEA) at Ipanema River, during one year, in order to evaluate the river in different conditions (seasons, temperature and rain period). The ground water was collected every six months. The analytical technique applied was ICP OES and the method conditions were optimized: wavelength, linearity, signal background ratio, detection and quantification limits. Data obtained in this work will contribute to evaluate the presence of barium at CEA region and nearby in order to compare it with current Brazilian regulations. (author)

  9. Identifying experimental methods to determine the effect of pain on attention: a review of pain, caffeine, alcohol and nicotine studies.

    Science.gov (United States)

    Moore, David J; Keogh, Edmund; Eccleston, Christopher

    2009-12-01

    To review published studies of the effects that pain and common psychopharmacological substances have on the attentional performance of healthy adults. To identify which attentional tasks have the greatest potential to investigate the effect of pain on attention and provide recommendations for future research. A search was conducted for reports of experimental studies of attention in the context of pain. This was supplemented with studies on attention and caffeine, nicotine and alcohol. Studies were included if they used a healthy adult sample, used experimental or quasi-experimental methods, were relevant to the study of attention or interruption of pain and/or examined the acute effects of a substance on attention. Thirty-two papers, with 49 different experimental studies were identified (12 pain, 21 nicotine, 7 caffeine, 9 alcohol). Fourteen different tasks were reviewed across six domains of attention. The most promising measures of attention were the continuous performance task, flanker task, endogenous pre-cuing task, n-back task, inhibition task and dual task. There are reliable tasks that could be used to determine the effects of pain on attention. Future research is required that develops the utility of these tasks to improve our understanding of the effects pain and analgesia have on attentional performance. Copyright (c) 2009 John Wiley & Sons, Ltd.

  10. Experimental determination and thermodynamic modeling of phase equilibrium and protein partitioning in aqueous two-phase systems containing biodegradable salts

    International Nuclear Information System (INIS)

    Perez, Brenda; Malpiedi, Luciana Pellegrini; Tubío, Gisela; Nerli, Bibiana; Alcântara Pessôa Filho, Pedro de

    2013-01-01

    Highlights: ► Binodal data of systems (water + polyethyleneglycol + sodium) succinate are reported. ► Pitzer model describes the phase equilibrium of systems formed by polyethyleneglycol and biodegradable salts satisfactorily. ► This simple thermodynamic framework was able to predict the partitioning behaviour of model proteins acceptably well. - Abstract: Phase diagrams of sustainable aqueous two-phase systems (ATPSs) formed by polyethyleneglycols (PEGs) of different average molar masses (4000, 6000, and 8000) and sodium succinate are reported in this work. Partition coefficients (Kps) of seven model proteins: bovine serum albumin, catalase, beta-lactoglobulin, alpha-amylase, lysozyme, pepsin, urease and trypsin were experimentally determined in these systems and in ATPSs formed by the former PEGs and other biodegradable sodium salts: citrate and tartrate. An extension of Pitzer model comprising long and short-range term contributions to the excess Gibbs free energy was used to describe the (liquid + liquid) equilibrium. Comparison between experimental and calculated tie line data showed mean deviations always lower than 3%, thus indicating a good correlation. The partition coefficients were modeled by using the same thermodynamic approach. Predicted and experimental partition coefficients correlated quite successfully. Mean deviations were found to be lower than the experimental uncertainty for most of the assayed proteins.

  11. Experimental determination of B R-12 attenuation coefficients utilizing photon spectrometry;Deteminacao experimental de coeficientes de atenuacao de BR-12 atraves de espectrometria de fotons

    Energy Technology Data Exchange (ETDEWEB)

    Almeida Junior, Jose N.; Terini, Ricardo A. [Pontificia Universidade Catolica de Sao Paulo (PUC-SP), Sao Paulo, SP (Brazil). Dept. de Fisica; Herdade, Silvio B. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Eletrotecnica e Energia (IEE). Secao Tecnica de Desenvolvimento Tecnologico em Saude

    2009-07-01

    In tests for quality assurance in mammography, it is common to use breast phantoms, with different compositions. One of the most used is the BR-12 phantom. There are few published experimental data on the attenuation of BR-12. Generally, the available attenuation coefficients are calculated from the composition of the coefficients determined for its components. In this work, the spectrometric method was used, with a CdTe detector, for X- and {gamma}-rays from radioactive sources of {sup 133}Ba and {sup 241}Am. The spectra of direct and attenuated by 0.5 cm of BR-12 beams were measured. From the ratio of intensities obtained for these radiations, it was possible to determine values of the attenuation coefficients from Beer's law. Results show coherence with previous data. The values of such coefficients are useful, for example, for calculations of absorbed dose (in BR-12), which have been made on other research activities of this group. (author)

  12. Determinación experimental de los coeficientes locales de transporte de humedad en almacenes soterrados. // Experimental determination of local humidity transport coefficients in underground warehouses.

    Directory of Open Access Journals (Sweden)

    Ma. D. Andrade Gregori

    2006-05-01

    Full Text Available En el trabajo se fundamentan los mecanismos de transporte de humedad que tienen lugar en almacenes soterrados dadas lascaracterísticas climáticas y geohidrològicas de Cuba. Se establece una analogía con la ley de Fick y se propone un modeloteórico que describe este mecanismo de transporte hacia las cavidades. Se determinó experimentalmente los coeficienteslocales de transporte de humedad para diferentes tipos de recubrimiento en paredes y diferentes formas geométricas de losalmacenes.Palabras claves: Almacenes, soterrado, humedad, conservación, coeficientes._______________________________________________________________________________Abstract.In this paper the mechanisms of humidity transport are explained. These mechanisms have place in underground warehousesaccording to the climatic and geohydrological characteristics of Cuba. An analogy with the Fick´s law is stated and it intends atheoretical model that describes this mechanism of transport toward the cavities. It was determined the local coefficients oftransport of humidity experimentally for different recover types in walls and different geometric forms of the warehouses.Key words: Store, buried, humidity, conservation, and coefficients.

  13. Experimental determination of the bulk temperature values in a nonisothermal flow of the chemically reacting nitrogen tetroxide

    International Nuclear Information System (INIS)

    Devojno, A.N.; Kolykhan, L.I.; Stepanenko, V.N.; Tverkovkin, B.E.; Uyutov, G.I.

    1975-01-01

    The technique and results of an experimental determination of mean mass temperatures of a cooled chemically active nitrogen tetroxide flowing in a circular tube under turbulent flow conditions are considered. The parameters range as follows: pressure-from 8.10 5 to 16.10 5 H/m 2 , flow temperature-from 140 deg to 550 deg C, Reynolds number-from 3,1.1g 5 , flow velocity-from 3.5 to 45 m/s. The gas temperature along the length of the test tube is measured with movable probe with a mixer and thermocouple in a stainless steel capillary 2mm in dia and the wall 0,2 mm thick. The mean-square deviations of measured temperature values from the predicted ones are about -0.9 and +1.8%. The obtained data show the predicted temperature values to be somewhat lower than the measured ones, the difference increasing with the distance to the test tube outlet. It may be explained by both unaccounted systematic experimental errors and errors in calculating the mean mass flow temperatures. The investigation described confirms the possibility of an experimental determination of the mean gas temperature along the cooled channel length by mean mass of a movable mixer with a single thermocouple

  14. Experimental determination of the yield stress curve of the scotch pine wood materials

    Science.gov (United States)

    Günay, Ezgi; Aygün, Cevdet; Kaya, Şükrü Tayfun

    2013-12-01

    Yield stress curve is determined for the pine wood specimens by conducting a series of tests. In this work, pinewood is modeled as a composite material with transversely isotropic fibers. Annual rings (wood grain) of the wood specimens are taken as the major fiber directions with which the strain gauge directions are aligned. For this purpose, three types of tests are arranged. These are tensile, compression and torsion loading tests. All of the tests are categorized with respect to fiber orientations and their corresponding loading conditions. Each test within these categories is conducted separately. Tensile and compression tests are conducted in accordance with standards of Turkish Standards Institution (TSE) whereas torsion tests are conducted in accordance with Standards Australia. Specimens are machined from woods of Scotch pine which is widely used in boat building industries and in other structural engineering applications. It is determined that this species behaves more flexibly than the others. Strain gauges are installed on the specimen surfaces in such a way that loading measurements are performed along directions either parallel or perpendicular to the fiber directions. During the test and analysis phase of yield stress curve, orientation of strain gauge directions with respect to fiber directions are taken into account. The diagrams of the normal stress vs. normal strain or the shear stress vs. shear strain are plotted for each test. In each plot, the yield stress is determined by selecting the point on the diagram, the tangent of which is having a slope of 5% less than the slope of the elastic portion of the diagram. The geometric locus of these selected points constitutes a single yield stress curve on σ1-σ2 principal plane. The resulting yield stress curve is plotted as an approximate ellipse which resembles Tsai-Hill failure criterion. The results attained in this work, compare well with the results which are readily available in the literature.

  15. A new experimental method for determining liquid density and surface tension

    Science.gov (United States)

    Chou, Kjo-Chih; Hu, Jian-Hong

    1991-02-01

    A summary concerning the measurement of liquid density relying on the Archimedes principle has been presented, based on which a new effective method with a specially designed bob for determining liquid density has been suggested. The application of this method to ethyl alcohol solution and liquid glycerol, as well as a theoretical error analysis, shows that this new method is significant, because not only can it simplify the procedure of measurement but it can also offer more precise results. Besides, this method can further provide surface tension or contact angle simultaneously. It is expected that this new method will find its application in hightemperature melts.

  16. Experimental determination of anomalous scattering lengths of samarium for thermal neutrons

    International Nuclear Information System (INIS)

    Engel, D.W.; Koetzle, T.F.

    1981-01-01

    Anomalous scattering lengths of natural Sm for thermal neutrons with wavelengths between 0.827 and 1.300 A have been determined using a single crysrtal of a Sm-complex of known structure. 140 selected reflections were measured at each wavelength and b 0 + b' and b'' refined in each case. The values obtained are in good agreement with theoretical values obtained from a Breit-Wigner calculation using tabulated resonance parameters for 149 Sm. A value of b 0 = 4.3 +- 0.2 fm is deduced from the diffraction experiment

  17. Experimental determination of systems suitable for study as monotectic binary metallic alloy solidification models

    Science.gov (United States)

    Smith, J. E., Jr.

    1985-01-01

    Transparent binary metallic alloy solidification models are important in attempts to understand the processes causing liquid-liquid and solid-liquid phase transformations in metallic alloy systems. These models permit visual observation of the phase transformation and the processes proceding solidification. The number of these transparent monotectic binary models needs to be expanded to distinguish between the unique and general phenomena observed. The expansion of the number of accurately determined monotectic phase diagrams of model systems, and contribution to a data base for eventual use with UNIFAC group contribution methods is examined.

  18. Experimental determination of plume properties in full-scale hydrogen-oxygen rockets

    Science.gov (United States)

    Brown, D. G.; Limbaugh, C. C.; Zaccardi, V. A.; Eskridge, R.

    1989-01-01

    An IR emission/absorption technique for determining radial profiles of static temperature and species partial pressure for cylindrically symmetric combustion gases typical of the effluent of turbine engines and liquid-propellant rockets is described. In the technique, the IR plume radiance and absorption is measured using a 1 x 256-element platinum silicide detector array which is filtered to obtain plume emission measurements in the H2O band near 3.0 microns. A minicomputer is employed to control data acquisition and reduction.

  19. Experimental determination of phase equilibria and reassessment of Ag-Pd system

    Energy Technology Data Exchange (ETDEWEB)

    Sopousek, Jiri, E-mail: sopousek@chemi.muni.c [Masaryk University, Faculty of Science, Department of Chemistry, Kotlarska 2, 611 37 Brno (Czech Republic); Zemanova, A. [Institute of Physics of Materials, ASCR, v.v.i., Zizkova 22, 616 62 Brno (Czech Republic); Vrestal, J.; Broz, P. [Masaryk University, Faculty of Science, Department of Chemistry, Kotlarska 2, 611 37 Brno (Czech Republic)

    2010-08-20

    The existing assessment of thermodynamic and phase equilibrium data in the Ag-Pd system was revised on the basis of calorimetric data for liquid Ag-Pd alloys published recently in the literature and on new determination of liquidus and solidus temperatures and activity data for Ag in liquid phase, using differential scanning calorimetry (DSC) coupled with Knudsen cell mass spectrometry (KC/MS). A substantially narrower liquid/fcc two-phase field in phase diagram as well as new non-ideal activity data were revealed.

  20. Experimental determination of the temperature in a small neighborhood of the gas infrared sources

    Directory of Open Access Journals (Sweden)

    Kuznetsov G.V.

    2015-01-01

    Full Text Available The results of the experiments carried out are the logical justification for the development of the heat transfer models in the air-filled enclosed areas which are determined by the walls of finite thickness and under conditions of the gas infrared sources operation. It was found that the air convection processes play an important role in formation of the thermal regimes of the areas heated by the radioactive flux coming from the upper boundary of such areas despite the low thermal conductivity of the gas.

  1. Method of magnetic susceptibility mapping of drilled cores. Experimental measurements for geologic structures determination

    International Nuclear Information System (INIS)

    Delrive, C.

    1993-01-01

    The evaluation of the safety of a deep geologic repository for dangerous materials requires the knowledge of the interstitial system of the surrounding host rock. A method is proposed for the determination of geologic structures (in particular fractures) from the magnetic susceptibility mapping of drilled cores. The feasibility of the method has been demonstrated using a SQUID magneto-gradient meter. A measurement tool using a new magnetic susceptibility captor and a testing bench have been developed. This tool allows the measurement of rocks with a magnetic susceptibility greater than 10 -5 SI units and can generate magnetic susceptibility maps with 4 x 4 mm 2 pixels. A magnetic visibility criterion has been defined which allows to foresee if a structure is visible or not. According to the measurements done, it is shown that any centimeter-scale structure with a sufficient magnetic contrast (20%) with respect to the matrix is visible. Therefore, the dip and the orientation of such structure can be determined with a 3 degree and a 5 degree precision, respectively. The position of the structure along the core axis is known with a 4 mm precision. On the other hand, about half of the magnetic contrasts observed do not correspond to the visual analyses and can be explained by very small variations of the mineralogic composition. This last point offers some interesting ways for future research using magnetic susceptibility mapping. (J.S.). 31 refs., 90 figs., 18 tabs., 2 photos., 6 appends

  2. Ultrasound determination of gestational age using placental thickness in female dogs: an experimental study.

    Science.gov (United States)

    Maldonado, André Luiz Louzada; Araujo Júnior, Edward; Mendonça, Débora Sartori; Nardozza, Luciano Marcondes Machado; Moron, Antonio Fernandes; Ajzen, Sérgio Aron

    2012-01-01

    Objective. To verify if the placental thickness allows determining the gestational age, evaluating the correlation between the referred gestational age with the studied one, and the accuracy of the placental thickness measurement (biometry) with fetal morphologic parameters in bitches. Methods. The placental thickness of 336 bitches of diverse breeds was evaluated. Bitches were divided in three groups by body weight: small, medium, and big large size. The gestations pregnancies were evaluated by ultrasound from the third week of gestation. An analysis was performed between the mean values of the gestational age obtained of placental thickness by adjustment of curves and the reported gestational age. Student's t-test was applied to compare the mean of reported and placental thickness gestational age. Significance was defined as P < 0.05. Results. A positive and statistically significant correlation exists between the placental thickness and gestational age. The expression that presents the best correlation coefficient and explanation was thickness of placenta = 0.021x gestational age -0.314. Conclusion. It is possible to determine the gestational age in relation to the placental thickness measured by ultrasound in bitches with a satisfactory accuracy in relation to fetal morphologic parameters as gestational vesicle, ribs, or kidneys.

  3. Taguchi experimental design to determine the taste quality characteristic of candied carrot

    Science.gov (United States)

    Ekawati, Y.; Hapsari, A. A.

    2018-03-01

    Robust parameter design is used to design product that is robust to noise factors so the product’s performance fits the target and delivers a better quality. In the process of designing and developing the innovative product of candied carrot, robust parameter design is carried out using Taguchi Method. The method is used to determine an optimal quality design. The optimal quality design is based on the process and the composition of product ingredients that are in accordance with consumer needs and requirements. According to the identification of consumer needs from the previous research, quality dimensions that need to be assessed are the taste and texture of the product. The quality dimension assessed in this research is limited to the taste dimension. Organoleptic testing is used for this assessment, specifically hedonic testing that makes assessment based on consumer preferences. The data processing uses mean and signal to noise ratio calculation and optimal level setting to determine the optimal process/composition of product ingredients. The optimal value is analyzed using confirmation experiments to prove that proposed product match consumer needs and requirements. The result of this research is identification of factors that affect the product taste and the optimal quality of product according to Taguchi Method.

  4. Experimental and numerical determination of the dynamic properties of the reactor building of Atucha II NPP

    International Nuclear Information System (INIS)

    Ceballos, M.A.; Car, E.J.; Prato, T.A.; Prato, C.A.; Alvarez, L.M.; Godoy, A.R.

    1995-01-01

    Determination of the dynamic properties of the reactor building of Atucha II NPP is carried out in order to: i) Obtain valuable information for seismic qualification of the plant, and ii) Assess some procedures for testing and analysis that are used in the process of seismic evaluation of existing nuclear facilities founded on Quaternary soil deposits. Both steady state and impulsive dynamic tests were performed but attention is centered here in tile techniques used to determine natural frequencies and modal damping ratios with impulsive tests. Numerical analyses were performed by means of a 3-D model model of the superstructure together with foundation stiffness coefficients derived in a separate paper from steady state vibration tests, and also from analysis with a 2-D F.E. model of the soil layers capable of approximating the 3-D features of the problem. The computed foundation stiffness coefficients are compared both with those obtained from the tests and from an axisymmetric F.E. model; results indicate that foundation stiffness coefficients calculated with F.E. models with soil parameters given by laboratory tests performed on cored samples are significantly lower than those given by the steady state vibration tests. (author)

  5. Ultrasound Determination of Gestational Age Using Placental Thickness in Female Dogs: An Experimental Study

    Directory of Open Access Journals (Sweden)

    André Luiz Louzada Maldonado

    2012-01-01

    Full Text Available Objective. To verify if the placental thickness allows determining the gestational age, evaluating the correlation between the referred gestational age with the studied one, and the accuracy of the placental thickness measurement (biometry with fetal morphologic parameters in bitches. Methods. The placental thickness of 336 bitches of diverse breeds was evaluated. Bitches were divided in three groups by body weight: small, medium, and big large size. The gestations pregnancies were evaluated by ultrasound from the third week of gestation. An analysis was performed between the mean values of the gestational age obtained of placental thickness by adjustment of curves and the reported gestational age. Student's t-test was applied to compare the mean of reported and placental thickness gestational age. Significance was defined as P<0.05. Results. A positive and statistically significant correlation exists between the placental thickness and gestational age. The expression that presents the best correlation coefficient and explanation was thickness of placenta = 0.021x gestational age −0.314. Conclusion. It is possible to determine the gestational age in relation to the placental thickness measured by ultrasound in bitches with a satisfactory accuracy in relation to fetal morphologic parameters as gestational vesicle, ribs, or kidneys.

  6. Experimental determination of the regional deposition of aerosol particles in the human respiratory tract

    Energy Technology Data Exchange (ETDEWEB)

    Stahlhofen, W.; Gebhart, J.; Heyder, J.

    1980-06-01

    The experimental techniques and the results of inhalation studies with radioaerosols on normal non-smokers for mouth-breathing are described and discussed. Monodisperse iron oxide particles tagged with /sup 198/Au are produced with a spinning top generator in the aerodynamic size range between 1 to 10 ..mu..m. An aerosol inhalation apparatus enables the subjects to breathe under standardized conditions with respect to tidal volume and breathing frequency. The calculation of total deposition is based upon measurements of the number of in- and exhaled particles per breath by means of photometric methods and pneumotachography. The retention of the radioactive particles present in the body after aerosol administration is measured with a body counter designed and constructed for these experiments. Retention measurements as functions of time after inhalation are carried out in extrathoracic-, chest- and stomach-position. The body counter consists of four shielded NaF(Tl)-dectors. Characteristic feature of the body counter is its low sensitivity to neighboring organs and to neighboring regions within the respiratory tract. For the evaluation of extrathoracic deposition, the activity measured in the stomach immediately after inhalation is added to extrathoracic activity. The elimination of material from the chest is found to be much slower for the material deposited in the alveolar region than for the amount deposited in the tracheobronchial tree. This allows the intrathoracic deposition to be divided into tracheolbronchial and alveolar deposition by means of the different slopes of the normalized chest retention function. Different normalized chest retention functions are presented and analyzed with respect to their different elimination rats belonging to the tracheobronchial and alveolar region. Total, tracheobronchial, alveolar and extrathoracic deposition data are reported in the aerodynamic diameter range between 1 and 10 ..mu..m.

  7. Experimental Determination of Bending Resonances of Millimeter Size PVF2 Cantilevers

    Directory of Open Access Journals (Sweden)

    David F. Thompson

    2003-07-01

    Full Text Available The polymer piezoelectric polvinylidene fluoride has found widespread use in sensors and actuators. The bending mode of piezoelectricity offers very high sensitivities and low mechanical input impedance, but has not been studied in as much detail for sensor applications. We report the dynamic electromechanical properties of millimeter size cantilevers made from electroded films of PVF2. All devices tested had a single polymer layer. Several resonances are found below 1 kHz and the experimentally observed resonance frequency dependence on cantilever thickness and length are seen to agree well with published models which take the properties of the electrodes into account. It is found that bending resonances are also modulated by the width of the cantilever. Therefore, though the length and thickness control the resonance frequency most strongly, the actual realized value can be fine-tuned by changing cantilever width and the electrode material and its thickness. Further, all resonances display high piezoelectric coupling coefficients (keff, ranging between 0.2 - 0.35. The data presented here will be extremely useful in the design of sensors and actuators for a number of applications, since the combination of millimeter size scales and high piezoelectric sensitivities in the low audio range can be realized with this marriage of polymeric materials and cantilever geometries. Such an array of sensors can be used in cochlear implant applications, and when integrated with a resonance interrogation circuit can be used for the detection of low frequency vibrations of large structures. If appropriate mass/elasticity sensitive layers are coated on the electrodes, such a sensor can be used for the detection of a wide range of chemicals and biochemicals.

  8. Mathematical Model Defining Volumetric Losses of Hydraulic Oil Compression in a Variable Capacity Displacement Pump

    Directory of Open Access Journals (Sweden)

    Paszota Zygmunt

    2015-01-01

    Full Text Available The objective of the work is to develop the capability of evaluating the volumetric losses of hydraulic oil compression in the working chambers of high pressure variable capacity displacement pump. Volumetric losses of oil compression must be determined as functions of the same parameters, which the volumetric losses due to leakage, resulting from the quality of design solution of the pump, are evaluated as dependent on and also as function of the oil aeration coefficient Ɛ. A mathematical model has been developed describing the hydraulic oil compressibility coefficient klc|Δppi;Ɛ;v as a relation to the ratio ΔpPi/pn of indicated increase ΔpPi of pressure in the working chambers and the nominal pressure pn, to the pump capacity coefficient bP, to the oil aeration coefficient  and to the ratio v/vnof oil viscosity v and reference viscosity vn. A mathematical model is presented of volumetric losses qpvc|ΔpPi;bp;;vof hydraulic oil compression in the pump working chambers in the form allowing to use it in the model of power of losses and energy efficiency

  9. Theoretical characterization of annular array as a volumetric optoacoustic ultrasound handheld probe

    Science.gov (United States)

    Kalkhoran, Mohammad Azizian; Vray, Didier

    2018-02-01

    Optoacoustic ultrasound (OPUS) is a promising hybridized technique for simultaneous acquisition of functional and morphological data. The optical specificity of optoacoustic leverages the diagnostic aptitude of ultrasonography beyond anatomy. However, this integration has been rarely practiced for volumetric imaging. The challenge lies in the effective imaging probes that preserve the functionality of both modalities. The potentials of a sparse annular array for volumetric OPUS imaging are theoretically investigated. In order to evaluate and optimize the performance characteristics of the probe, series of analysis in the framework of system model matrix was carried out. The two criteria of voxel crosstalk and eigenanalysis have been employed to unveil information about the spatial sensitivity, aliasing, and number of definable spatial frequency components. Based on these benchmarks, the optimal parameters for volumetric handheld probe are determined. In particular, the number, size, and the arrangement of the elements and overall aperture dimension were investigated. The result of the numerical simulation suggests that the segmented-annular array of 128 negatively focused elements with 1λ × 20λ size, operating at 5-MHz central frequency showcases a good agreement with the physical requirement of both imaging systems. We hypothesize that these features enable a high-throughput volumetric passive/active ultrasonic imaging system with great potential for clinical applications.

  10. Interactive stereoscopic rendering of volumetric environments.

    Science.gov (United States)

    Wan, Ming; Zhang, Nan; Qu, Huamin; Kaufman, Arie E

    2004-01-01

    We present an efficient stereoscopic rendering algorithm supporting interactive navigation through large-scale 3D voxel-based environments. In this algorithm, most of the pixel values of the right image are derived from the left image by a fast 3D warping based on a specific stereoscopic projection geometry. An accelerated volumetric ray casting then fills the remaining gaps in the warped right image. Our algorithm has been parallelized on a multiprocessor by employing effective task partitioning schemes and achieved a high cache coherency and load balancing. We also extend our stereoscopic rendering to include view-dependent shading and transparency effects. We have applied our algorithm in two virtual navigation systems, flythrough over terrain and virtual colonoscopy, and reached interactive stereoscopic rendering rates of more than 10 frames per second on a 16-processor SGI Challenge.

  11. Benchmark calculations for evaluation methods of gas volumetric leakage rate

    International Nuclear Information System (INIS)

    Asano, R.; Aritomi, M.; Matsuzaki, M.

    1998-01-01

    A containment function of radioactive materials transport casks is essential for safe transportation to prevent the radioactive materials from being released into environment. Regulations such as IAEA standard determined the limit of radioactivity to be released. Since is not practical for the leakage tests to measure directly the radioactivity release from a package, as gas volumetric leakages rates are proposed in ANSI N14.5 and ISO standards. In our previous works, gas volumetric leakage rates for several kinds of gas from various leaks were measured and two evaluation methods, 'a simple evaluation method' and 'a strict evaluation method', were proposed based on the results. The simple evaluation method considers the friction loss of laminar flow with expansion effect. The strict evaluating method considers an exit loss in addition to the friction loss. In this study, four worked examples were completed for on assumed large spent fuel transport cask (Type B Package) with wet or dry capacity and at three transport conditions; normal transport with intact fuels or failed fuels, and an accident in transport. The standard leakage rates and criteria for two kinds of leak test were calculated for each example by each evaluation method. The following observations are made based upon the calculations and evaluations: the choked flow model of ANSI method greatly overestimates the criteria for tests ; the laminar flow models of both ANSI and ISO methods slightly overestimate the criteria for tests; the above two results are within the design margin for ordinary transport condition and all methods are useful for the evaluation; for severe condition such as failed fuel transportation, it should pay attention to apply a choked flow model of ANSI method. (authors)

  12. Experimental determination of quantum-well lifetime effect on large-signal resonant tunneling diode switching time

    Energy Technology Data Exchange (ETDEWEB)

    Growden, Tyler A.; Berger, Paul R., E-mail: pberger@ieee.org [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Brown, E. R.; Zhang, Weidong [Departments of Physics and Electrical Engineering, Wright State University, Dayton, Ohio 45435 (United States); Droopad, Ravi [Ingram School of Engineering, Texas State University, San Marcos, Texas 78666 (United States)

    2015-10-12

    An experimental determination is presented of the effect the quantum-well lifetime has on a large-signal resonant tunneling diode (RTD) switching time. Traditional vertical In{sub 0.53}Ga{sub 0.47}As/AlAs RTDs were grown, fabricated, and characterized. The switching time was measured with a high-speed oscilloscope and found to be close to the sum of the calculated RC-limited 10%–90% switching time and the quantum-well quasibound-state lifetime. This method displays experimental evidence that the two intrinsic resonant-tunneling characteristic times act independently, and that the quasibound-state lifetime then serves as a quantum-limit on the large-signal speed of RTDs.

  13. Experimental Determination of Ballistic Performance of Composite Material Kevlar 29 and Alumina Powder/ Epoxy by Spherical Projectile

    Directory of Open Access Journals (Sweden)

    Luay Hashem Abbud

    2016-12-01

    Full Text Available In this study, a response of hybrid composite laminate woven fiber Kevlar29 – Al2O3 Powder/ Epoxy subjected to high velocity impact loading is presented. The energy absorbed due to impact of small rigid projectile on composite materials targets is determined experimentally. The energy absorbed due to impact of hemispherical projectiles on the developed composite laminates is investigated. The results revealed the maximum ballistic limit at impact velocity is found to be 390.87 ± 6 m/s for an the 18 mm target thickness. The ballistic limit velocity predictions are based on the theoretical method presented from another article. The initial velocity and residual velocity results showed good is agreement compared with the predicted results of Ipson and Recht equations. With 5.4 % of accuracy based on the experimental value for the theoretical model for ballistic limit velocity.

  14. Experimental determination of the phase boundary between kornelite and pentahydrated ferric sulfate at 0.1MPa

    Science.gov (United States)

    Kong, W.G.; Wang, A.; Chou, I.-Ming

    2011-01-01

    Recent findings of various ferric sulfates on Mars emphasize the importance of understanding the fundamental properties of ferric sulfates at temperatures relevant to that of Martian surface. In this study, the phase boundary between kornelite (Fe2(SO4)3.7H2O) and pentahydrated ferric sulfate (Fe2(SO4)3.5H2O) was experimentally determined using the humidity-buffer technique together with gravimetric measurements and Raman spectroscopy at 0.1MPa in the 36-56??C temperature range. Through the thermodynamic analysis of our experimental data, the enthalpy change (-290.8??0.3kJ/mol) and the Gibbs free energy change (-238.82??0.02kJ/mol) for each water molecule of crystallization in the rehydration of pentahydrated ferric sulfate to kornelite were obtained. ?? 2011 Elsevier B.V.

  15. Simulation and Experimental Determination of Technological Liquid Molding Parameters of Tubing Basalt Insulation

    Directory of Open Access Journals (Sweden)

    Yu. V. Badanina

    2015-01-01

    Full Text Available The article is dedicated to one of the most important and urgent tasks in mechanical engineering development - the creation of low-density and environmentally-friendly thermoinsulation from available cheap basalt fibers for products to operate at temperatures up to 700°C.One of the most effective applications of such thermo-insulation is to develop and provide highly porous coatings from short basalt fibers by liquid filtration for tubing (T to supply superheated up to 420° C steam under pressure of 35 MPa in the deep layers with severe highviscosity oil. Tubing with the short low-density basalt insulation can be used for a greater depth than the vacuum-insulated tubing, which are also called "thermo-cases", and do not fully meet business needs for long-term reliability of oil vacuum tubes, too large mass per unit length of their design and, as a consequence, the impossibility to use such pipes for deep wells.The aim of the work is to simulate a liquid filtration process of short fibers and determine technological parameters of producing thermal insulation coatings of tubing pipes from basalt fibers and mineral binder shaped as cylinders and cylindrical shells. The paper proposes a mathematical model of free filtration deposition of short fibers from liquid slurry, which describes dynamics of creating thermal insulation products and allows us to determine the rational parameters of their manufacturing process. It shows methods to improve the products quality while forming the thermal insulation by filtration through additional vacuum deposition of a filtrate chamber and the final prepressing of sediment layer, giving dimensions and shape to the final product.The paper defines a prescription hydro mass composition. It shows that to increase the compressive strength of highly fibrous rings and cylindrical shells it is necessary to use based on oxide А12O3 5-7% by weight mineral binder, which fixes basalt fibers in places of their contacts. It

  16. Theoretical and experimental approach to determine pollutant levels in an urban area

    Energy Technology Data Exchange (ETDEWEB)

    Solisio, C.; Cecco, I. de; Ferraiolo, G. [Genoa Univ. (Italy). Inst. of Chemical Engineering Science and Technology; Ruaro, R.

    1995-12-31

    Simulative techniques, carried out by means of scale physical models, prove to be particularly useful because they allow to optimize those prevention and protection measures aimed at the undesired effect reduction. Among the various scale models, the wind tunnel is one of the most common physical models used to simulate real environmental conditions, reproduced in suitable reduced scale by dimensional analysis. Physical modeling, mainly wind tunnel, is typically employed to study plants in complex terrain or to determine how building turbulence can affect dispersion from staks. Moreover, simulative techniques set-up is not simple and it needs particular careful regarding to define its capable to simulate real environmental conditions. The present article deals with the scale simulative technique through wind tunnel, applied to the study about dispersion atmospheric phenomenon. Set-up procedures are discussed, then preliminary results about pollutant dispersion in a street of Genoa (Italy) characterized by great traffic vehicular traffic are showed too. (author)

  17. Renal microvascular disease determines the responses to revascularization in experimental renovascular disease.

    Science.gov (United States)

    Chade, Alejandro R; Kelsen, Silvia

    2010-08-01

    Percutaneous transluminal renal angioplasty (PTRA) is the most frequent therapeutic approach to resolving renal artery stenosis (RAS). However, renal function recovers in only 30% of the cases. The causes of these poor outcomes are still unknown. We hypothesized that preserving the renal microcirculation distal to RAS will improve the responses to PTRA. RAS was induced in 28 pigs. In 14, vascular endothelial growth factor (VEGF)-165 0.05 microg/kg was infused intrarenally (RAS+VEGF). Single-kidney function was assessed in all pigs in vivo using ultrafast CT after 6 weeks. Observation of half of the RAS and RAS+VEGF pigs was completed. The other half underwent PTRA and repeated VEGF, and CT studies were repeated 4 weeks later. Pigs were then euthanized, the stenotic kidney removed, renal microvascular (MV) architecture reconstructed ex vivo using 3D micro-CT, and renal fibrosis quantified. The degree of RAS and hypertension were similar in RAS and RAS+VEGF. Renal function and MV density were decreased in RAS but improved in RAS+VEGF. PTRA largely resolved RAS, but the improvements of hypertension and renal function were greater in RAS+VEGF+PTRA than in RAS+PTRA, accompanied by a 34% increase in MV density and decreased fibrosis. Preservation of the MV architecture and function in the stenotic kidney improved the responses to PTRA, indicating that renal MV integrity plays a role in determining the responses to PTRA. This study indicates that damage and early loss of renal MV is an important determinant of the progression of renal injury in RAS and instigates often irreversible damage.

  18. Computational identification and experimental characterization of substrate binding determinants of nucleotide pyrophosphatase/phosphodiesterase 7

    Directory of Open Access Journals (Sweden)

    Parrill Abby L

    2011-12-01

    Full Text Available Abstract Background Nucleotide pyrophosphatase/phosphodiesterase 7 (NPP7 is the only member of the mammalian NPP enzyme family that has been confirmed to act as a sphingomyelinase, hydrolyzing sphingomyelin (SM to form phosphocholine and ceramide. NPP7 additionally hydrolyzes lysophosphatidylcholine (LPC, a substrate preference shared with the NPP2/autotaxin(ATX and NPP6 mammalian family members. This study utilizes a synergistic combination of molecular modeling validated by experimental site-directed mutagenesis to explore the molecular basis for the unique ability of NPP7 to hydrolyze SM. Results The catalytic function of NPP7 against SM, LPC, platelet activating factor (PAF and para-nitrophenylphosphorylcholine (pNPPC is impaired in the F275A mutant relative to wild type NPP7, but different impacts are noted for mutations at other sites. These results are consistent with a previously described role of F275 to interact with the choline headgroup, where all substrates share a common functionality. The L107F mutation showed enhanced hydrolysis of LPC, PAF and pNPPC but reduced hydrolysis of SM. Modeling suggests this difference can be explained by the gain of cation-pi interactions with the choline headgroups of all four substrates, opposed by increased steric crowding against the sphingoid tail of SM. Modeling also revealed that the long and flexible hydrophobic tails of substrates exhibit considerable dynamic flexibility in the binding pocket, reducing the entropic penalty that might otherwise be incurred upon substrate binding. Conclusions Substrate recognition by NPP7 includes several important contributions, ranging from cation-pi interactions between F275 and the choline headgroup of all substrates, to tail-group binding pockets that accommodate the inherent flexibility of the lipid hydrophobic tails. Two contributions to the unique ability of NPP7 to hydrolyze SM were identified. First, the second hydrophobic tail of SM occupies a second

  19. Experimental determination of the regional deposition of aerosol particles in the human respiratory tract.

    Science.gov (United States)

    Stahlhofen, W; Gebhart, J; Heyder, J

    1980-06-01

    The experimental techniques and the results of inhalation studies with radioaerosols on normal non-smokers for mouth-breathing are described and discussed. Monodisperse iron oxide particles tagged with 198Au are produced with a spinning top generator in the aerodynamic size range between 1 to 10 micrometers. An aerosol inhalation apparatus enables the subjects to breathe under standardized conditions with respect to tidal volume and breathing frequency. The calculation of total deposition is based upon measurements of the number of in- and exhaled particles per breath by means of photometric methods and pneumotachography. The retention of the radioactive particles present in the body after aerosol administration is measured with a body counter designed and constructed for these experiments. Retention measurements as functions of time after inhalation are carried out in extrathoracic-, chest- and stomach-position. The body counter consists of four shielded NaF(TI)-detectors. The geometrical arrangement, the collimation and the shielding of the four detectors have been optimized by computer calculations in such a way that the response of the counter is independent of the distribution of activity within the chest. Another characteristic feature of the body counter is its low sensitivity to neighboring organs and to neighboring regions within the respiratory tract. For the evaluation of extrathoracic deposition, the activity measured in the stomach immediately after inhalation is added to extrathoracic activity. The elimination of material from the chest (intrathoracic airways) is found to be much slower for the material deposited in the alveolar region (non-ciliated air spaces) than for the amount deposited in the tracheobronchial tree (ciliated airways). This allows the intrathoracic deposition to be divided into tracheobronchial and alveolar deposition by means of the different slopes of the normalized chest retention function. Different normalized chest retention

  20. Experimental determination of soil heat storage for the simulation of heat transport in a coastal wetland

    Science.gov (United States)

    Swain, Michael; Swain, Matthew; Lohmann, Melinda; Swain, Eric

    2012-01-01

    Two physical experiments were developed to better define the thermal interaction of wetland water and the underlying soil layer. This information is important to numerical models of flow and heat transport that have been developed to support biological studies in the South Florida coastal wetland areas. The experimental apparatus consists of two 1.32. m diameter by 0.99. m tall, trailer-mounted, well-insulated tanks filled with soil and water. A peat-sand-soil mixture was used to represent the wetland soil, and artificial plants were used as a surrogate for emergent wetland vegetation based on size and density observed in the field. The tanks are instrumented with thermocouples to measure vertical and horizontal temperature variations and were placed in an outdoor environment subject to solar radiation, wind, and other factors affecting the heat transfer. Instruments also measure solar radiation, relative humidity, and wind speed.Tests indicate that heat transfer through the sides and bottoms of the tanks is negligible, so the experiments represent vertical heat transfer effects only. The temperature fluctuations measured in the vertical profile through the soil and water are used to calibrate a one-dimensional heat-transport model. The model was used to calculate the thermal conductivity of the soil. Additionally, the model was used to calculate the total heat stored in the soil. This information was then used in a lumped parameter model to calculate an effective depth of soil which provides the appropriate heat storage to be combined with the heat storage in the water column. An effective depth, in the model, of 5.1. cm of wetland soil represents the heat storage needed to match the data taken in the tank containing 55.9. cm of peat/sand/soil mix. The artificial low-density laboratory sawgrass reduced the solar energy absorbed by the 35.6. cm of water and 55.9. cm of soil at midday by less than 5%. The maximum heat transfer into the underlying peat-sand-soil mix

  1. Absorbed dose determination using experimental and analytical predictions of x-ray spectra

    Science.gov (United States)

    Edwards, David Lee

    1999-10-01

    Electron beam welding in a vacuum is a technology that NASA is investigating as a joining technique for manufacture of space structures. The interaction of energetic electrons with metal produces x-rays. This investigation characterizes the x-ray environment due to operation of an in-vacuum electron beam welding tool and provides recommendations for adequate radiation shielding for astronauts performing the in-vacuum electron beam welding. NASA, in a joint venture with the Russian Space Agency, was scheduled to perform a series of welding in space experiments on board the United States Space Shuttle. This series of experiments was named the International Space Welding Experiment (ISWE). The hardware associated with the ISWE was leased to NASA, by the Paton Welding Institute (PWI) in Ukraine, for ground based welding experiments in preparation for flight. Two ground tests were scheduled, using the ISWE electron beam welding tool, to characterize the radiation exposure to an astronaut during the operation of the ISWE. These radiation exposure tests used Thermoluminescence Dosimeters (TLD's) shielded with material currently used by astronauts during Extra Vehicular Activities (EVA) to measure the radiation dose. The TLD's were exposed to x- ray radiation generated by operation of the ISWE in- vacuum electron beam welding tool. This investigation was the first known application of TLD's to measure absorbed dose from x-rays of energy less than 10 keV. The ISWE hardware was returned to Ukraine before the issue of adequate shielding for the astronauts was completely verified. Therefore alternate experimental and analytical methods were developed to measure and predict the x-ray spectral and intensity distribution generated by ISWE electron beam impact with metal. These x-ray spectra were normalized to an equivalent ISWE exposure then used to calculate the absorbed radiation dose to astronauts. These absorbed dose values were compared to TLD measurements obtained during

  2. Effect of low-shrinkage monomers on the physicochemical properties of experimental composite resin.

    Science.gov (United States)

    He, Jingwei; Garoushi, Sufyan; Vallittu, Pekka K; Lassila, Lippo

    2018-01-01

    This study was conducted to determine whether novel experimental low-shrinkage dimethacrylate co-monomers could provide low polymerization shrinkage composites without sacrifice to degree of conversion, and mechanical properties of the composites. Experimental composites were prepared by mixing 28.6 wt% of bisphenol-A-glycidyl dimethacrylate based resin matrix ( bis -GMA) with various weight-fractions of co-monomers; tricyclo decanedimethanol dacrylate (SR833s) and isobornyl acrylate (IBOA) to 71.4 wt% of particulate-fillers. A composite based on bis -GMA/TEGDMA (triethylene glycol dimethacrylate) was used as a control. Fracture toughness and flexural strength were determined for each experimental material following international standards. Degree of monomer-conversion (DC%) was determined by FTIR spectrometry. The volumetric shrinkage in percent was calculated as a buoyancy change in distilled water by means of the Archimedes' principle. Polymerization shrinkage-strain and -stress of the specimens were measured using the strain-gage technique and tensilometer, respectively with respect to time. Statistical analysis revealed that control group had the highest double-bond conversion ( p   .05). Volumetric shrinkage and shrinkage stress decreased with increasing IBOA concentration. Replacing TEGDMA with SR833s and IBOA can decrease the volumetric shrinkage, shrinkage strain, and shrinkage stress of composite resins without affecting the mechanical properties. However, the degree of conversion was also decreased.

  3. Experimental results for the rapid determination of the freezing point of fuels

    Science.gov (United States)

    Mathiprakasam, B.

    1984-01-01

    Two methods for the rapid determination of the freezing point of fuels were investigated: an optical method, which detected the change in light transmission from the disappearance of solid particles in the melted fuel; and a differential thermal analysis (DTA) method, which sensed the latent heat of fusion. A laboratory apparatus was fabricated to test the two methods. Cooling was done by thermoelectric modules using an ice-water bath as a heat sink. The DTA method was later modified to eliminate the reference fuel. The data from the sample were digitized and a point of inflection, which corresponds to the ASTM D-2386 freezing point (final melting point), was identified from the derivative. The apparatus was modifified to cool the fuel to -60 C and controls were added for maintaining constant cooling rate, rewarming rate, and hold time at minimum temperature. A parametric series of tests were run for twelve fuels with freezing points from -10 C to -50 C, varying cooling rate, rewarming rate, and hold time. Based on the results, an optimum test procedure was established. The results showed good agreement with ASTM D-2386 freezing point and differential scanning calorimetry results.

  4. Experimental determination of the key heat transfer mechanisms in pharmaceutical freeze-drying.

    Science.gov (United States)

    Ganguly, Arnab; Nail, Steven L; Alexeenko, Alina

    2013-05-01

    The study is aimed at quantifying the relative contribution of key heat transfer modes in lyophilization. Measurements of vial heat transfer rates in a laboratory-scale freeze-dryer were performed using pure water, which was partially sublimed under various conditions. The separation distance between the shelf and the vial was systematically varied, and sublimation rates were determined gravimetrically. The heat transfer rates were observed to be independent of separation distance between the vial and the shelf and linearly dependent on pressure in the free molecular flow limit, realized at low pressures (120 mTorr), heat transfer rates were independent of pressure and inversely proportional to separation distance. Previous heat transfer studies in conventional freeze-drying cycles have attributed a dominant portion of the total heat transfer to radiation, the rest to conduction, whereas convection has been found to be insignificant. Although the measurements reported here confirm the significance of the radiative and gas conduction components, the convective component has been found to be comparable to the gas conduction contribution at pressures greater than 100 mTorr. The current investigation supports the conclusion that the convective component of the heat transfer cannot be ignored in typical laboratory-scale freeze-drying conditions. Copyright © 2013 Wiley Periodicals, Inc.

  5. Proteins labelling with 125I and experimental determination of their specific activity

    International Nuclear Information System (INIS)

    Caro, R.A.; Ciscato, V.A.; Giacomini, S.M.V. de; Quiroga, S.; Radicella, R.

    1975-11-01

    A standardization of the labelling technique of proteins with 125 I and the control of the obtained products, principally their specific activities was performed, in order to utilize them correctly in radioimmunoassays. The quantities of chloramine-T and sodium metabisulphite were lowered, with regard to the original method, to 3.6 and 9.6 μg respectively. Under these conditions, optimal yields and radioiodinated proteins with good immunological activities were obtained. It was found that the specific activity calculated, as usual, from the yield obtained by electrophoresis, is higher than the real value. For these reasons the yields and the corresponding specific activities were determined from ascending chromatographies performed with 70 per cent methanol as solvent, during two hours in darkness. The radioimmunoassay displacement curves obtained with proteins labelled which the proposed method and the specific activities of which were calculated from their radiochromatographic patterns, were reproducible and gave a percentage of bound radioiodinated protein in the absence of cold protein of 50 +- 4. (author) [es

  6. Multislice spiral computed tomography to determine the effects of a recruitment maneuver in experimental lung injury

    Energy Technology Data Exchange (ETDEWEB)

    Henzler, Dietrich; Rossaint, Rolf [University Hospital, RWTH Aachen, Anesthesiology Department, Aachen (Germany); Mahnken, Andreas H.; Wildberger, Joachim E.; Guenther, Rolf W. [University Hospital of the RWTH Aachen, Clinic of Diagnostic Radiology, Aachen (Germany); Kuhlen, Ralf [University Hospital of the RWTH Aachen, Operative Intensive Care Department, Aachen (Germany)

    2006-06-15

    Although recruitment of atelectatic lung is a common aim in acute respiratory distress syndrome (ARDS), the effects of a recruitment maneuver have not been assessed quantitatively. By multislice spiral CT (MSCT), we analyzed the changes in lung volumes calculated from the changes in the CT values of hyperinflated (V{sub HYP}), normally (V{sub NORM}), poorly (V{sub POOR}) and nonaerated (V{sub NON}) lung in eight mechanically ventilated pigs with saline lavage-induced acute lung injury before and after a recruitment maneuver. This was compared to single slice analysis near the diaphragm. The increase in aerated lung was mainly for V{sub POOR} and the less in V{sub NORM}. Total lung volume and intrathoracic gas increased. No differences were found for tidal volumes measured by spirometry or determined by CT. The inspiratory-expiratory volume differences were not different after the recruitment maneuver in V{sub NON} (from 62{+-}18 ml to 43{+-}26 ml, P=0.114), and in V{sub NORM} (from 216{+-}51 ml to 251{+-}37 ml, P=0.102). Single slice analysis significantly underestimated the increase in normally and poorly aerated lung. Quantitative analysis of lung volumes by whole lung MSCT revealed the increase of poorly aerated lung as the main mechanism of a standard recruitment maneuver. MSCT can provide additional information as compared to single slice CT. (orig.)

  7. Regulation of Caveolin-1 Expression Determines Early Brain Edema After Experimental Focal Cerebral Ischemia.

    Science.gov (United States)

    Choi, Kang-Ho; Kim, Hyung-Seok; Park, Man-Seok; Kim, Joon-Tae; Kim, Ja-Hae; Cho, Kyung-Ah; Lee, Min-Cheol; Lee, Hong-Joon; Cho, Ki-Hyun

    2016-05-01

    Most patients with cerebral infarction die of brain edema because of the breakdown of the blood-brain barrier (BBB) in ischemic tissue. Caveolins (a group of proteins) are key modulators of vascular permeability; however, a direct role of caveolin-1 (Cav-1) in the regulation of BBB permeability during ischemic injury has yet to be identified. Cav-1 expression was measured by immunoblotting after photothrombotic ischemia. A direct functional role of Cav-1 in cerebral edema and BBB permeability during cerebral ischemia was investigated by genetic manipulation (gene disruption and re-expression) of Cav-1 protein expression in mice. There was a significant correlation between the extent of BBB disruption and the Cav-1 expression. In Cav-1-deficient (Cav-1(-/-)) mice, the extent of BBB disruption after cerebral ischemia was increased compared with wild-type (Cav-1(+/+)) mice, whereas the increase in cerebral edema volume was ameliorated by lentiviral-mediated re-expression of Cav-1. Furthermore, Cav-1(-/-) mice had significantly higher degradation of tight junction proteins and proteolytic activity of matrix metalloproteinase than Cav-1(+/+) mice. Conversely, re-expression of Cav-1 in Cav-1(-/-) mice restored tight junction protein expression and reduced matrix metalloproteinase proteolytic activity. These results indicate that Cav-1 is a critical determinant of BBB permeability. Strategies for regulating Cav-1 represent a novel therapeutic approach to controlling BBB disruption and subsequent neurological deterioration during cerebral ischemia. © 2016 American Heart Association, Inc.

  8. Experimental determination of the passive/active transition for iron in 1-M sulfuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Russell, P.P.; Newman, J.

    1984-06-01

    Current-voltage curves from three iron rotating disks are obtained using a polarization device which permits determination of the transition region between the active and passive states. Diameters of the three electrodes are 0.494,0.298, and 0.0986 cm, respectively. Results from the smallest electrode have the least amount of ohmic distortion. Trends in the data, which are observed as the electrode size is decreased, form the basis for the conclusions that are drawn from this work. Analysis of these trends indicates that the active-passive transition is characterized by a nearly vertical line on a current vs potential plot. The Z shaped nature of the current-voltage curves, reported by Epelboin et al, is entirely due to ohmic potential drop in the solution. Analysis of the data, within the framework of a mathematical model presented by Law and Newman, indicates that the average current density on the active portion of the disk increases as the size of the active area decreases during the passivation process.

  9. Determination of thorium and plutonium in AHWR experimental (Th, 1%Pu)O2 MOX fuel after microwave dissolution

    International Nuclear Information System (INIS)

    Fulzele, Ajit K.; Malav, R.K.; Pandey, Ashish; Kapoor, Y.S.; Kumar, Manish; Singh, Mamta; Das, D.K.; Prakash, Amrit; Behere, P.G.; Afzal, Mohd

    2013-01-01

    This paper describes determination of thorium and plutonium in experimental (Th, 1%Pu)O 2 AHWR (Advanced Heavy Water Reactor) MOX fuel samples after dissolution by microwave. Time taken to dissolve ∼ 2g of MOX sample by conventional IR heating technique in conc. HNO 3 + 0.05 M HF mixture is about 35-40 hours while using microwave dissolution technique it is ∼ 2 hours. Hence, with the help of microwave dissolution technique analysis time for each sample has been reduced from week to a day. The PuO 2 content (wt%) in the MOX pellets was within specification limit, (1.0±0.1)%. (author)

  10. Determination of molar enthalpy of sublimation in case of orotic acid as obtained from experimental and computational data

    Science.gov (United States)

    Marochkin, Ilya I.; Altova, Ekaterina P.; Chilingarov, Norbert S.; Vilkova, Anna L.; Shishkov, Igor F.

    2018-03-01

    Saturated vapor pressure, ln(p/Pa) = (-21316 ± 511)/(T/K)+(41.64 ± 0.11), and enthalpy of sublimation of orotic acid, Δsub Hm0 (Tm) = 177 ± 4 kJ/mol, were determined by means of Knudsen effusion mass spectrometry in the temperature range of 423÷493 K. The computational approaches supported the experimental results reported. The theoretical estimation of the gas-phase enthalpy of formation for orotic acid was done with different working reactions used.

  11. Experimental determination of the Planck’s constant by observation of the discharge current of a capacitor

    OpenAIRE

    dos Santos, Erick Santana; Departamento de Física, Instituto Federal da Bahia; Menezes Jr., Roberto dos Santos; Departamento de Física, Instituto Federal da Bahia; da Silva Santana, Victor Mancir; Instituto de Física, Universidade Federal da Bahia

    2015-01-01

    In this paper, we present an experimental method for the determination of Planck’s constant, based on the measurement of the discharge current of a capacitor on a LED, without the use of resistors. To develop this, we use a capacitor connected in parallel to a LED and observe the voltage on the capacitor during its discharge along with the current flowing through the ammeter connected in series to the LED. At the instant when the current becomes zero, the voltage applied on the LED correspond...

  12. Experimental determination of relative light conversion factors of TLD-100 for protons with energies from 2.0 to 9.0 MeV

    International Nuclear Information System (INIS)

    Schmidt, P.; Fellinger, J.; Huebner, K.; Henniger, J.

    1985-01-01

    Relative light conversion factors (RLCF) for heavy charged particles (protons, deuterons, recoils) are needed for the calculation of the neutron sensitivity of thermoluminescent (TL) detectors. Such light conversion factors can be determined experimentally. A method is represented for the experimental determination of RLCF. The described experimental facility gives the possibility of irradiation of different luminophor samples with heavy charged particles and flux determination and particle spectrometry at the same time. For the determination of RLCF the doses are needed which are applicated at the irradiation with heavy charged particles and gamma radiation, respectively, and the according detector readings at the TL evaluation. The problems arising at the dose determination are discussed. With this experimental facility the RLCF for TLD-100 for protons were determined. The relative light conversion factors determined according to the light sum method as well as the peak height method are summarizinhly represented and discussed. Furthermore a comparison of the glow curves is made after gamma and proton irradiation

  13. Volumetric imaging using single chip integrated CMUT-on-CMOS IVUS array.

    Science.gov (United States)

    Tekes, Coskun; Zahorian, Jaime; Gurun, Gokce; Satir, Sarp; Xu, Toby; Hochman, Michael; Degertekin, F Levent

    2012-01-01

    An intravascular ultrasound (IVUS) catheter that can provide forward viewing volumetric ultrasound images would be an invaluable clinical tool for guiding interventions. Single chip integration of front-end electronics with capacitive micromachined ultrasonic transducers (CMUTs) is highly desirable to reduce the interconnection complexity and enable miniaturization in IVUS catheters. For this purpose we use the monolithic CMUT-on-CMOS integration where CMUTs are fabricated directly on top of pre-processed CMOS wafers. This minimizes parasitic capacitances associated with connection lines. We have recently implemented a system design including all the required electronics using 0.35-µm CMOS process integrated with a 1.4-mm diameter CMUT array. In this study, we present the experimental volumetric imaging results from an ex-vivo chicken heart phantom. The imaging results demonstrate that the single-chip forward looking IVUS (FL-IVUS) system with monolithically integrated electronics has potential to visualize the front view of coronary arteries.

  14. Determination of the meniscus shape of a negative ion beam from an experimentally obtained beam profile

    Science.gov (United States)

    Ichikawa, M.; Kojima, A.; Chitarin, G.; Agostinetti, P.; Aprile, D.; Baltador, C.; Barbisan, M.; Delogu, R.; Hiratsuka, J.; Marconato, N.; Nishikiori, R.; Pimazzoni, A.; Sartori, E.; Serianni, G.; Tobari, H.; Umeda, N.; Veltri, P.; Watanabe, K.; Yoshida, M.; Antoni, V.; Kashiwagi, M.

    2017-08-01

    In order to understand the physics mechanism of a negative ion extraction in negative ion sources, an emission surface of the negative ions around an aperture at a plasma grid, so-called a meniscus, has been analyzed by an inverse calculation of the negative ion trajectory in a two dimensional beam analysis code. In this method, the meniscus is defined as the final position of the negative ion trajectories which are inversely calculated from the measured beam profile to the plasma grid. In a case of the volume-produced negative ions, the calculated meniscus by the inverse calculation was similar to that obtained in conventional beam simulation codes for positive ion extractions such as BEAMORBT and SLACCAD. The negative ion current density was uniform along the meniscus. This indicates that the negative ions produced in the plasma are transported to the plasma grid uniformly as considered in the transportation of the positive ions. However, in a surface production case of negative ions, where the negative ions are generated near the plasma grid with lower work function by seeding cesium, the current density in the peripheral region of the meniscus close to the plasma grid surface was estimated to be 2 times larger than the center region, which suggested that the extraction process of the surface-produced negative ions was much different with that for the positive ions. Because this non-uniform profile of the current density made the meniscus shape strongly concave, the beam extracted from the peripheral region could have a large divergence angle, which might be one of origins of so-called beam halo. This is the first results of the determination of the meniscus based on the experiment, which is useful to improve the prediction of the meniscus shape and heat loads based on the beam trajectories including beam halo.

  15. Experimental determination of soot refractive index in the infrared; Determination experimentale de l'indice de refraction de particules de suie dans l'infrarouge

    Energy Technology Data Exchange (ETDEWEB)

    Ouf, F.X.; Vendel, J. [Institut de Radioprotection et de Surete Nucleaire (IRSN), DRU/SERAC, Lab. de Physique et Metrologie des Aerosols, 91 - Gif sur Yvette (France); Ouf, F.X.; Coppalle, A.; Weil, M.E.; Yon, J. [CORIA - Complexe de Recherche Interprofessionnel en Aerothermochimie, UMR 6614, 76 - Saint Etienne du Rouvray (France)

    2007-07-01

    The study of physical properties of soot particles produced during combustion is a complex subject but of a great interest within the framework of the study of the safety of an installation, with respect to the fire hazard. These characteristics are, in this case, particularly useful in order to predict the behav of containment barriers in situation of fire, but also in order to estimate the contribution of these particles to radiative transfers. The aim of this study is to determine the radiative properties of soot particles produced during combustion. A specific device, which establishes extinction and vertical-vertical scattering coefficients, has been developed and has allowed to determine the refractive index of soot particles in the infrared. This determination also needed the establishment of size distribution and morphological properties of soot aggregates. We present in this document the experimental device developed, and the validation of this device on latex spheres which optical properties are well known. First results of extinction coefficients will be presented and will underline the similar optical behaviour of different soot aggregates. Values of refractive index will be detailed and discussed, and a direct application of these values will be carried out in order to determine the soot volume fraction. A comparison with reference method will underline the efficiency of our method. We will conclude on the validity of the information brought by this device and on the prospects of this study. A discussion is included, on the utility of mean values of refractive index and on the determination of total emissivity of soot particles. (authors)

  16. Stereo vision for fully automatic volumetric flow measurement in urban drainage structures

    Science.gov (United States)

    Sirazitdinova, Ekaterina; Pesic, Igor; Schwehn, Patrick; Song, Hyuk; Satzger, Matthias; Weingärtner, Dorothea; Sattler, Marcus; Deserno, Thomas M.

    2017-06-01

    Overflows in urban drainage structures, or sewers, must be prevented on time to avoid their undesirable consequences. An effective monitoring system able to measure volumetric flow in sewers is needed. Existing stateof-the-art technologies are not robust against harsh sewer conditions and, therefore, cause high maintenance expenses. Having the goal of fully automatic, robust and non-contact volumetric flow measurement in sewers, we came up with an original and innovative idea of a vision-based system for volumetric flow monitoring. On the contrast to existing video-based monitoring systems, we introduce a second camera to the setup and exploit stereo-vision aiming of automatic calibration to the real world. Depth of the flow is estimated as the difference between distances from the camera to the water surface and from the camera to the canal's bottom. Camerato-water distance is recovered automatically using large-scale stereo matching, while the distance to the canal's bottom is measured once upon installation. Surface velocity is calculated using cross-correlation template matching. Individual natural particles in the flow are detected and tracked throughout the sequence of images recorded over a fixed time interval. Having the water level and the surface velocity estimated and knowing the geometry of the canal we calculate the discharge. The preliminary evaluation has shown that the average error of depth computation was 3 cm, while the average error of surface velocity resulted in 5 cm/s. Due to the experimental design, these errors are rough estimates: at each acquisition session the reference depth value was measured only once, although the variation in volumetric flow and the gradual transitions between the automatically detected values indicated that the actual depth level has varied. We will address this issue in the next experimental session.

  17. Experimental subcritical reactivity determinations employing APSD measurements with pulse mode detectors in the IPEN/MB-01 reactor

    International Nuclear Information System (INIS)

    Santos, Adimir dos; Lee, Seung Min; Diniz, Ricardo; Jerez, Rogerio

    2011-01-01

    This work aims to determine experimentally the subcritical reactivity levels of several configurations of the IPEN/MB-01 reactor in an approach based on the subcritical kinetic model developed by Gandini and Salvatores. The procedure employs the measurements of the APSD (Auto Power Spectral Density) using pulse mode detectors. The proposed approach is based only on measured quantities such as counting rates and the parameters arising from the least square approach of the APSD. Other difficult quantity such as detector efficiencies is not needed in the method. Several measurements of APSD were performed in varying degrees of sub-criticality (up to around -7000 pcm). The APSD data were least-square fitted to get the prompt decay mode (α). Beside the startup source, an external neutron sources of Am-Be was installed near the core in order to improve neutron count statistics. The final experimental results are of very good quality. The experiment shows clearly that the classical one point kinetic theory cannot describe the measured reactivity. MCNP K eff results were compared to the corresponding experimental results. The agreement was fairly good. (author)

  18. Arsenic determination in gasoline by hydride generation atomic absorption spectroscopy combined with a factorial experimental design approach

    Energy Technology Data Exchange (ETDEWEB)

    Jemmla Meira Trindade; Aldalea Lopes Marques; Gisele Simone Lopes; Edmar Pereira Marques; Jiujun Zhang [Federal University of Maranhao UFMA, Sao Luis (Brazil). Department of Chemistry

    2006-10-15

    Three locally collected gasoline samples were analyzed for arsenic content using factorial experimental design (FED) with hydride generation atomic absorption spectrometry (HGAAS). Five factors (including the reduction agent flow, the acid flow, the sample flow, the reductor concentration and the acid concentration) in two levels (low and high) were used in this optimization process. In order to design the surface response, five levels of central composite with 15 central points were down-selected. The results were compared with those determined by graphite furnace atomic absorption spectrometry (GFAAS) and a 95% confidence interval (regression procedure) was obtained. The HGAAS and GFAAS measurement sensitivities determined arsenic levels of 0.02 {mu}g L{sup -1} and 0.08 {mu}g L{sup -1}, respectively. 23 refs., 6 figs., 8 tabs.

  19. Osmotic dehydration and convective drying of coconut slices: Experimental determination and description using one-dimensional diffusion model

    Directory of Open Access Journals (Sweden)

    Wilton Pereira da Silva

    2014-06-01

    Full Text Available Mass migrations in coconut slices during osmotic dehydration and drying are described using a diffusion model with boundary condition of the third kind. The osmotic dehydration experiment was performed at 35°Brix (water and sucrose and 40 °C. The convective drying experiments were performed at 50, 60 and 70 °C. The one-dimensional solution of the diffusion equation for an infinite slab was coupled with an optimizer to determine the effective mass diffusivities D and convective mass transfer coefficients h of the five processes studied. The analyses of the obtained results indicate that there is a good agreement between each experimental dataset and the corresponding simulation using D and h determined by optimization.

  20. Spatial and volumetric changes of retroperitoneal sarcomas during pre-operative radiotherapy

    International Nuclear Information System (INIS)

    Wong, Philip; Dickie, Colleen; Lee, David; Chung, Peter; O’Sullivan, Brian; Letourneau, Daniel; Xu, Wei; Swallow, Carol; Gladdy, Rebecca; Catton, Charles

    2014-01-01

    Purpose: To determine the positional and volumetric changes of retroperitoneal sarcomas (RPS) during pre-operative external beam radiotherapy (PreRT). Material and methods: After excluding 2 patients who received chemotherapy prior to PreRT and 15 RPS that were larger than the field-of-view of cone-beam CT (CBCT), the positional and volumetric changes of RPS throughout PreRT were characterized in 19 patients treated with IMRT using CBCT image guidance. Analysis was performed on 118 CBCT images representing one image per week of those acquired daily during treatment. Intra-fraction breathing motions of the gross tumor volume (GTV) and kidneys were measured in 22 RPS patients simulated using 4D-CT. Fifteen other patients were excluded whose tumors were incompletely imaged on CBCT or who received pre-RT chemotherapy. Results: A GTV volumetric increase (mean: 6.6%, p = 0.035) during the first 2 weeks (CBCT1 vs. CBCT2) of treatment was followed by GTV volumetric decrease (mean: 4%, p = 0.009) by completion of radiotherapy (CBCT1 vs. CBCT6). Internal margins of 8.6, 15 and 15 mm in the lateral, anterior/posterior and superior/inferior directions would be required to account for inter-fraction displacements. The extent of GTV respiratory motion was significantly (p < 0.0001) correlated with more superiorly positioned tumors. Conclusion: Inter-fraction CBCT provides important volumetric and positional information of RPS which may improve PreRT quality and prompt re-planning. Planning target volume may be reduced using online soft-tissue matching to account for interfractional displacements of GTVs. Important breathing motion occurred in superiorly placed RPS supporting the utility of 4D-CT planning

  1. A volumetric model-based 2D to 3D registration method for measuring kinematics of natural knees with single-plane fluoroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Tsung-Yuan; Lu, Tung-Wu; Chen, Chung-Ming; Kuo, Mei-Ying; Hsu, Horng-Chaung [Institute of Biomedical Engineering, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10051, Taiwan (China); Institute of Biomedical Engineering, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10051, Taiwan (China) and Department of Physical Therapy, China Medical University, Taichung 40402, Taiwan (China); Department of Orthopaedic Surgery, China Medical University Hospital, Taichung 40447, Taiwan (China)

    2010-03-15

    Purpose: Accurate measurement of the three-dimensional (3D) rigid body and surface kinematics of the natural human knee is essential for many clinical applications. Existing techniques are limited either in their accuracy or lack more realistic experimental evaluation of the measurement errors. The purposes of the study were to develop a volumetric model-based 2D to 3D registration method, called the weighted edge-matching score (WEMS) method, for measuring natural knee kinematics with single-plane fluoroscopy to determine experimentally the measurement errors and to compare its performance with that of pattern intensity (PI) and gradient difference (GD) methods. Methods: The WEMS method gives higher priority to matching of longer edges of the digitally reconstructed radiograph and fluoroscopic images. The measurement errors of the methods were evaluated based on a human cadaveric knee at 11 flexion positions. Results: The accuracy of the WEMS method was determined experimentally to be less than 0.77 mm for the in-plane translations, 3.06 mm for out-of-plane translation, and 1.13 deg. for all rotations, which is better than that of the PI and GD methods. Conclusions: A new volumetric model-based 2D to 3D registration method has been developed for measuring 3D in vivo kinematics of natural knee joints with single-plane fluoroscopy. With the equipment used in the current study, the accuracy of the WEMS method is considered acceptable for the measurement of the 3D kinematics of the natural knee in clinical applications.

  2. Experimental determination of the high-temperature rate constant for the reaction of OH with sec-butanol.

    Science.gov (United States)

    Pang, Genny A; Hanson, Ronald K; Golden, David M; Bowman, Craig T

    2012-10-04

    The overall rate constant for the reaction of OH with sec-butanol [CH(3)CH(OH)CH(2)CH(3)] was determined from measurements of the near-first-order OH decay in shock-heated mixtures of tert-butylhydroperoxide (as a fast source of OH) with sec-butanol in excess. Three kinetic mechanisms from the literature describing sec-butanol combustion were used to examine the sensitivity of the rate constant determination to secondary kinetics. The overall rate constant determined can be described by the Arrhenius expression 6.97 × 10(-11) exp(-1550/T[K]) cm(3) molecule(-1) s(-1), valid over the temperature range of 888-1178 K. Uncertainty bounds of ±30% were found to adequately account for the uncertainty in secondary kinetics. To our knowledge, the current data represent the first efforts toward an experimentally determined rate constant for the overall reaction of OH with sec-butanol at combustion-relevant temperatures. A rate constant predicted using a structure-activity relationship from the literature was compared to the current data and previous rate constant measurements for the title reaction at atmospheric-relevant temperatures. The structure-activity relationship was found to be unable to correctly predict the measured rate constant at all temperatures where experimental data exist. We found that the three-parameter fit of 4.95 × 10(-20)T(2.66) exp(+1123/T[K]) cm(3) molecule(-1) s(-1) better describes the overall rate constant for the reaction of OH with sec-butanol from 263 to 1178 K.

  3. Experimental determination of net protein charge and A(tot) and K(a) of nonvolatile buffers in canine plasma.

    Science.gov (United States)

    Constable, Peter D; Stämpfli, Henry R

    2005-01-01

    Acid-base abnormalities frequently are present in sick dogs. The mechanism for an acid-base disturbance can be determined with the simplified strong ion approach, which requires accurate values for the total concentration of plasma nonvolatile buffers (A(tot)) and the effective dissociation constant for plasma weak acids (K(a)). The aims of this study were to experimentally determine A(tot) and K(a) values for canine plasma. Plasma was harvested from 10 healthy dogs; the concentrations of quantitatively important strong ions (Na+, K+, Ca2+, Mg2+, Cl-, L-lactate) and nonvolatile buffer ions (total protein, albumin, phosphate) were determined; and the plasma was tonometered with CO2 at 37 degrees C. Strong ion difference (SID) was calculated from the measured strong ion concentrations, and nonlinear regression was used to estimate values for A(tot) and K(a), which were validated with data from an in vitro and in vivo study. Mean (+/- SD) values for canine plasma were A(tot) = (17.4 +/- 8.6) mM (equivalent to 0.273 mmol/g of total protein or 0.469 mmol/g of albumin); K(a) = (0.17 +/- 0.11) x 10(-7); pK(a) = 7.77. The calculated SID for normal canine plasma (pH = 7.40; P(CO2) = 37 mm Hg; [total protein] = 64 g/L) was 27 mEq/L. The net protein charge for normal canine plasma was 0.25 mEq/g of total protein or 0.42 mEq/g of albumin. Application of the experimentally determined values for A(tot), K(a), and net protein charge should improve understanding of the mechanism for complex acid-base disturbances in dogs.

  4. Experimental determination of liquidus H2O contents of haplogranite at deep-crustal conditions

    Science.gov (United States)

    Makhluf, A. R.; Newton, R. C.; Manning, C. E.

    2017-09-01

    The liquidus water content of a haplogranite melt at high pressure ( P) and temperature ( T) is important, because it is a key parameter for constraining the volume of granite that could be produced by melting of the deep crust. Previous estimates based on melting experiments at low P (≤0.5 GPa) show substantial scatter when extrapolated to deep crustal P and T (700-1000 °C, 0.6-1.5 GPa). To improve the high-P constraints on H2O concentration at the granite liquidus, we performed experiments in a piston-cylinder apparatus at 1.0 GPa using a range of haplogranite compositions in the albite (Ab: NaAlSi3O8)—orthoclase (Or: KAlSi3O8)—quartz (Qz: SiO2)—H2O system. We used equal weight fractions of the feldspar components and varied the Qz between 20 and 30 wt%. In each experiment, synthetic granitic composition glass + H2O was homogenized well above the liquidus T, and T was lowered by increments until quartz and alkali feldspar crystalized from the liquid. To establish reversed equilibrium, we crystallized the homogenized melt at the lower T and then raised T until we found that the crystalline phases were completely resorbed into the liquid. The reversed liquidus minimum temperatures at 3.0, 4.1, 5.8, 8.0, and 12.0 wt% H2O are 935-985, 875-900, 775-800, 725-775, and 650-675 °C, respectively. Quenched charges were analyzed by petrographic microscope, scanning electron microscope (SEM), X-ray diffraction (XRD), and electron microprobe analysis (EMPA). The equation for the reversed haplogranite liquidus minimum curve for Ab36.25Or36.25Qz27.5 (wt% basis) at 1.0 GPa is T = - 0.0995 w_{{{H}_{ 2} {O}}}^{ 3} + 5.0242w_{{{H}_{ 2} {O}}}^{ 2} - 88.183 w_{{{H}_{ 2} {O}}} + 1171.0 for 0 ≤ w_{{{H}_{ 2} {O}}} ≤ 17 wt% and T is in °C. We present a revised P - T diagram of liquidus minimum H2O isopleths which integrates data from previous determinations of vapor-saturated melting and the lower pressure vapor-undersaturated melting studies conducted by other workers on

  5. Experimental Determination of the Fracture Toughness and Brittleness of the Mancos Shale, Utah.

    Science.gov (United States)

    Chandler, Mike; Meredith, Phil; Crawford, Brian

    2013-04-01

    non-linearity. This produces hysteresis during cyclic loading, allowing for the calculation of a brittleness coefficient using the residual displacement after successive loading cycles. This can then be used to define a brittleness corrected Fracture Toughness, KIcc. We report anisotropic KIcc values and a variety of supporting measurements made on the Mancos Shale in the three principle Mode-I crack orientations (Arrester, Divider and Short-Transverse) using a modified Short-Rod sample geometry. The Mancos is an Upper Cretaceous shale from western Colorado and eastern Utah with a relatively high siliclastic content for a gas target formation. The Short-Rod methodology involves the propagation of a crack through a triangular ligament in a chevron-notched cylindrical sample [3]. A very substantial anisotropy is observed in the loading curves and KIcc values for the three crack orientations, with the Divider orientation having KIcc values 25% higher than the other orientations. The measured brittleness for these Mancos shales is in the range 1.5-2.1; higher than for any other rocks we have found in the literature. This implies that the material is extremely non-linear. Increases in KIcc with increasing confining pressure are also investigated, as Shale Gas reservoirs occur at depths where confining pressure may be as high as 35MPa and temperature as high as 100oC. References [1] C.A. Green, P. Styles & B.J. Baptie, "Preese Hall Shale Gas Fracturing", Review & Recommendations for Induced Seismic Mitigation, 2012. [2] N.R. Warpinski & M.B. Smith, "Rock Mechanics and Fracture Geometry", Recent advances in Hydraulic Fracturing, SPE Monograms, Vol. 12, pp. 57-80, 1990. [3] F. Ouchterlony, "International Society for Rock Mechanics Commision on Testing Methods: Suggested Methods for Determining the Fracture Toughness of Rock", International Journal of Rock Mechanics and Mining Science & Geomechanics Abstracts, Vol. 25, 1988.

  6. An Ice Track Equipped with Optical Sensors for Determining the Influence of Experimental Conditions on the Sliding Velocity

    Science.gov (United States)

    Lungevics, J.; Jansons, E.; Gross, K. A.

    2018-02-01

    The ability to slide on ice has previously focused on the measurement of friction coefficient rather than the actual sliding velocity that is affected by it. The performance can only be directly measured by the sliding velocity, and therefore the objective was to design and setup a facility to measure velo-city, and determine how experimental conditions affect it. Optical sensors were placed on an angled ice track to provide sliding velocity measurements along three sections and the velocity for the total sliding distance. Experimental conditions included the surface roughness, ambient temperature and load. The effect of roughness was best reported with a Criterion of Contact that showed a similar sliding velocity for metal blocks abraded with sand paper smoother than 600 grit. Searching for the effect of temperature, the highest sliding velocity coincided with the previously reported lowest coefficient of ice friction. Load showed the greatest velocity increase at temperatures closer to the ice melting point suggesting that in such conditions metal block overcame friction forces more easily than in solid friction. Further research needs to be conducted on a longer ice track, with larger metal surfaces, heavier loads and higher velocities to determine how laboratory experiments can predict real-life situations.

  7. An Ice Track Equipped with Optical Sensors for Determining the Influence of Experimental Conditions on the Sliding Velocity

    Directory of Open Access Journals (Sweden)

    Lungevics J.

    2018-02-01

    Full Text Available The ability to slide on ice has previously focused on the measurement of friction coefficient rather than the actual sliding velocity that is affected by it. The performance can only be directly measured by the sliding velocity, and therefore the objective was to design and setup a facility to measure velo-city, and determine how experimental conditions affect it. Optical sensors were placed on an angled ice track to provide sliding velocity measurements along three sections and the velocity for the total sliding distance. Experimental conditions included the surface roughness, ambient temperature and load. The effect of roughness was best reported with a Criterion of Contact that showed a similar sliding velocity for metal blocks abraded with sand paper smoother than 600 grit. Searching for the effect of temperature, the highest sliding velocity coincided with the previously reported lowest coefficient of ice friction. Load showed the greatest velocity increase at temperatures closer to the ice melting point suggesting that in such conditions metal block overcame friction forces more easily than in solid friction. Further research needs to be conducted on a longer ice track, with larger metal surfaces, heavier loads and higher velocities to determine how laboratory experiments can predict real-life situations.

  8. Effect of experimental and sample factors on dehydration kinetics of mildronate dihydrate: mechanism of dehydration and determination of kinetic parameters.

    Science.gov (United States)

    Bērziņš, Agris; Actiņš, Andris

    2014-06-01

    The dehydration kinetics of mildronate dihydrate [3-(1,1,1-trimethylhydrazin-1-ium-2-yl)propionate dihydrate] was analyzed in isothermal and nonisothermal modes. The particle size, sample preparation and storage, sample weight, nitrogen flow rate, relative humidity, and sample history were varied in order to evaluate the effect of these factors and to more accurately interpret the data obtained from such analysis. It was determined that comparable kinetic parameters can be obtained in both isothermal and nonisothermal mode. However, dehydration activation energy values obtained in nonisothermal mode showed variation with conversion degree because of different rate-limiting step energy at higher temperature. Moreover, carrying out experiments in this mode required consideration of additional experimental complications. Our study of the different sample and experimental factor effect revealed information about changes of the dehydration rate-limiting step energy, variable contribution from different rate limiting steps, as well as clarified the dehydration mechanism. Procedures for convenient and fast determination of dehydration kinetic parameters were offered. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  9. Experimental determination of the heat transfer and cold storage characteristics of a microencapsulated phase change material in a horizontal tank

    International Nuclear Information System (INIS)

    Allouche, Yosr; Varga, Szabolcs; Bouden, Chiheb; Oliveira, Armando C.

    2015-01-01

    Highlights: • Cold storage characteristics in latent and sensible heat storage mediums were studied. • Thermo-physical characterization of the phase change material was carried out. • A non-Newtonian shear thickening behavior of the phase change material was observed. • An energy storage enhancement (53%) was observed in the latent heat storage medium. - Abstract: In the present paper, the performance of a microencapsulated phase change material (in 45% w/w concentration) for low temperature thermal energy storage, suitable for air conditioning applications is studied. The results are compared to a sensible heat storage unit using water. Thermo-physical properties such as the specific heat, enthalpy variation, thermal conductivity and density are also experimentally determined. The non-Newtonian shear-thickening behavior of the phase change material slurry is quantified. Thermal energy performance is experimentally determined for a 100 l horizontal tank. The heat transfer between the heat transfer fluid and the phase change material was provided by a tube-bundle heat exchanger inside the tank. The results show that the amount of energy stored using the phase change material is 53% higher than for water after 10 h of charging, for the same storage tank volume. It was found that the heat transfer coefficient between the phase change material and the tube wall increases during the phase change temperature range, however it remains smaller than the values obtained for water

  10. Development of method for experimental determination of wheel–rail contact forces and contact point position by using instrumented wheelset

    International Nuclear Information System (INIS)

    Bižić, Milan B; Petrović, Dragan Z; Tomić, Miloš C; Djinović, Zoran V

    2017-01-01

    This paper presents the development of a unique method for experimental determination of wheel–rail contact forces and contact point position by using the instrumented wheelset (IWS). Solutions of key problems in the development of IWS are proposed, such as the determination of optimal locations, layout, number and way of connecting strain gauges as well as the development of an inverse identification algorithm (IIA). The base for the solution of these problems is the wheel model and results of FEM calculations, while IIA is based on the method of blind source separation using independent component analysis. In the first phase, the developed method was tested on a wheel model and a high accuracy was obtained (deviations of parameters obtained with IIA and really applied parameters in the model are less than 2%). In the second phase, experimental tests on the real object or IWS were carried out. The signal-to-noise ratio was identified as the main influential parameter on the measurement accuracy. Тhе obtained results have shown that the developed method enables measurement of vertical and lateral wheel–rail contact forces Q and Y and their ratio Y / Q with estimated errors of less than 10%, while the estimated measurement error of contact point position is less than 15%. At flange contact and higher values of ratio Y / Q or Y force, the measurement errors are reduced, which is extremely important for the reliability and quality of experimental tests of safety against derailment of railway vehicles according to the standards UIC 518 and EN 14363. The obtained results have shown that the proposed method can be successfully applied in solving the problem of high accuracy measurement of wheel–rail contact forces and contact point position using IWS. (paper)

  11. Volumetric real-time imaging using a CMUT ring array.

    Science.gov (United States)

    Choe, Jung Woo; Oralkan, Ömer; Nikoozadeh, Amin; Gencel, Mustafa; Stephens, Douglas N; O'Donnell, Matthew; Sahn, David J; Khuri-Yakub, Butrus T

    2012-06-01

    A ring array provides a very suitable geometry for forward-looking volumetric intracardiac and intravascular ultrasound imaging. We fabricated an annular 64-element capacitive micromachined ultrasonic transducer (CMUT) array featuring a 10-MHz operating frequency and a 1.27-mm outer radius. A custom software suite was developed to run on a PC-based imaging system for real-time imaging using this device. This paper presents simulated and experimental imaging results for the described CMUT ring array. Three different imaging methods--flash, classic phased array (CPA), and synthetic phased array (SPA)--were used in the study. For SPA imaging, two techniques to improve the image quality--Hadamard coding and aperture weighting--were also applied. The results show that SPA with Hadamard coding and aperture weighting is a good option for ring-array imaging. Compared with CPA, it achieves better image resolution and comparable signal-to-noise ratio at a much faster image acquisition rate. Using this method, a fast frame rate of up to 463 volumes per second is achievable if limited only by the ultrasound time of flight; with the described system we reconstructed three cross-sectional images in real-time at 10 frames per second, which was limited by the computation time in synthetic beamforming.

  12. Construction and calibration of TDR probes for volumetric water content estimation in a Distroferric Red Latosol

    OpenAIRE

    Soncela, Rosimaldo; Sampaio, Silvio C.; Vilas Boas, Marcio A.; Tavares, Maria H. F.; Smanhotto, Adriana

    2013-01-01

    The determination of volumetric water content of soils is an important factor in irrigation management. Among the indirect methods for estimating, the time-domain reflectometry (TDR) technique has received a significant attention. Like any other technique, it has advantages and disadvantages, but its greatest disadvantage is the need of calibration and high cost of acquisition. The main goal of this study was to establish a calibration model for the TDR equipment, Trase System Model 6050X1, t...

  13. Experimental determination of net protein charge and A(tot) and K(a) of nonvolatile buffers in human plasma.

    Science.gov (United States)

    Staempfli, Henry R; Constable, Peter D

    2003-08-01

    The mechanism for an acid-base disturbance can be determined by using the strong ion approach, which requires species-specific values for the total concentration of plasma nonvolatile buffers (Atot) and the effective dissociation constant for plasma weak acids (Ka). The aim of this study was to experimentally determine Atot and Ka values for human plasma by using in vitro CO2 tonometry. Plasma Pco2 was systematically varied from 25 to 145 Torr at 37 degrees C, thereby altering plasma pH over the physiological range of 6.90-7.55, and plasma pH, Pco2, and concentrations of quantitatively important strong ions (Na+, K+, Ca2+, Mg2+, Cl-, lactate) and buffer ions (total protein, albumin, phosphate) were measured. Strong ion difference was estimated, and nonlinear regression was used to calculate Atot and Ka from the measured pH and Pco2 and estimated strong ion difference; the Atot and Ka values were then validated by using a published data set (Figge J, Rossing TH, and Fencl V, J Lab Clin Med 117: 453-467, 1991). The values (mean +/- SD) were as follows: Atot = 17.2 +/- 3.5 mmol/l (equivalent to 0.224 mmol/g of protein or 0.378 mmol/g of albumin); Ka = 0.80 +/- 0.60 x 10-7; negative log of Ka = 7.10. Mean estimates were obtained for strong ion difference (37 meq/l) and net protein charge (13+.0 meq/l). The experimentally determined values for Atot, Ka, and net protein charge should facilitate the diagnosis and treatment of acid-base disturbances in critically ill humans.

  14. Recovery coefficients for the quantification of the arterial input function from dynamic pet measurements: experimental and theoretical determination

    International Nuclear Information System (INIS)

    Brix, G.; Bellemann, M.E.; Hauser, H.; Doll, J.

    2002-01-01

    Aim: For kinetic modelling of dynamic PET data, the arterial input function can be determined directly from the PET scans if a large artery is visualized on the images. It was the purpose of this study to experimentally and theoretically determine recovery coefficients for cylinders as a function of the diameter and level of background activity. Methods: The measurements were performed using a phantom with seven cylinder inserts (φ = 5-46 mm). The cylinders were filled with an aqueous 68 Ga solution while the main chamber was filled with a 18 F solution in order to obtain a varying concentration ratio between the cylinders and the background due to the different isotope half lives. After iterative image reconstruction, the activity concentrations were measured in the center of the cylinders and the recovery coefficients were calculated as a function of the diameter and the background activity. Based on the imaging properties of the PET system, we also developed a model for the quantitative assessment of recovery coefficients. Results: The functional dependence of the measured recovery data from the cylinder diameter and the concentration ratio is well described by our model. For dynamic PET measurements, the recovery correction must take into account the decreasing concentration ratio between the blood vessel and the surrounding tissue. Under the realized measurement and data analysis conditions, a recovery correction is required for vessels with a diameter of up to 25 mm. Conclusions: Based on the experimentally verified model, the activity concentration in large arteries can be calculated from the measured activity concentration in the blood vessel and the background activity. The presented approach offers the possibility to determine the arterial input function for pharmacokinetic PET studies non-invasively from large arteries (especially the aorta). (orig.) [de

  15. Experimental determination and evaluation of the friction behavior of geosynthetics; Experimentelle Ermittlung und Bewertung des Reibungsverhaltens von Geokunststoffen

    Energy Technology Data Exchange (ETDEWEB)

    Heinemann, Maik

    2016-08-17

    In many fields of geotechnical engineering geosynthetics have established itself as an alternative to common used earth materials. Particularly in landfill sealing systems many different types of geosynthetics are used together. In embankments geosynthetics form inclined planes. The safety against sliding must be proved for all contact surfaces. For this purpose, the knowledge of the friction behavior of the geosynthetics is required. Normally, the friction behavior is modeled analytically with the Coulomb failure criterion. The Coulomb friction parameters usually must be determined experimentally. In spite of the good state of the art and numerous studies into geosynthetics, in detail, there are still issues relating to the determination of friction behavior of geosynthetics, to the application of the Coulomb failure criterion and to the assessment of the friction parameters with a view to the time- and temperature-dependent behavior of synthetics. The main objective of this work is to contribute to a reliable determination of the friction behavior and to a correct assessment of the evaluated test results as the basis for a reliable and economical dimensioning of structures with geosynthetics. For this, the measurement technique of a standard large direct shear box was upgraded by the author, so that the effective normal stress can be measured below the test surface. Also tests with very small normal stresses can be carried out with this modification. Furthermore, a force-controlled test device was designed for studies of the influences arising from long-term combined compressive and shear loads and temperature. Based on experimental investigations inadequacies in the current experimental procedure are identified. In addition, the impact of factors are quantified, which are often ignored or considered to be marginal in practice. With further experimental investigations it is demonstrated that the linear Coulomb failure criterion is valid for limited normal stress

  16. Volumetric Optoacoustic Temperature Mapping in Photothermal Therapy.

    Science.gov (United States)

    Landa, Francisco Javier Oyaga; Deán-Ben, Xosé Luís; Sroka, Ronald; Razansky, Daniel

    2017-08-29

    Photothermal therapy and ablation are commonplace medical procedures employed for treatment of tumors, vascular and brain abnormalities as well as other disorders that require selective destruction of tissues. Yet, accurate mapping of the dynamic temperature field distribution in the treated region represents an unmet clinical need, strongly affecting the clinical outcome of these interventions. We introduce a fast three-dimensional temperature mapping method based on real-time optoacoustic sensing of the treated region coupled with a thermal-diffusion-based model of heat distribution in tissues. Deviations of the optoacoustic temperature readings provided at 40  ms intervals remained below 10% in tissue-mimicking phantom experiments for temperature elevations above 3 °C, as validated by simultaneous thermocouple measurements. Performance of the new method to dynamically estimate the volumetric temperature distribution was further showcased in post-mortem mouse imaging experiments. The newly discovered capacity to non-invasively measure the temperature map in an entire treated volume with both high spatial and temporal resolutions holds potential for improving safety and efficacy of light-based therapeutic interventions.

  17. Radiofrequency volumetric reduction for masseteric hypertrophy.

    Science.gov (United States)

    Jin Park, Young; Woo Jo, Yong; Bang, Sa Ik; Kim, Hyung Joon; Lim, So Young; Mun, Goo Hyun; Hyon, Won Sok; Oh, Kap Sung

    2007-01-01

    Masseteric hypertrophy occurs frequently among Asians, including Koreans, because of racial characteristics and dietary habits. It is thought to be an unpleasant feature, especially because of its strong and masculine impression. Recently, the authors developed a method for the volumetric reduction of hypertrophied masseter muscles using radiofrequency energy to correct the squared facial appearance caused by the hypertrophy. This study was performed to investigate the effects of radiofrequency applied to reduce hypertrophied masseter muscles of patients who sought an aesthetic alternative for a slim, smooth, and feminine-looking lower facial contour. A total of 340 patients were treated. The patients usually recognized the volume change 3 to 6 weeks after treatment, and an objective volume reduction was observed within 3 months of the operation. The range of the reduction in the masseter thickness, as measured by ultrasonic examination at a 6-month postoperative follow-up visit, was 10% to 60% (mean, 27%). Most of the patients could eat a nearly normal diet after 4 weeks and were satisfied with the improved aesthetic contour lines of their lower face. Radiofrequency-induced coagulation tissue necrosis of the masseter did not cause any infections or limitations of mouth opening, and the clinical improvement was well maintained after the treatment.

  18. Sampling and TDR probe insertion in the determination of the volumetric soil water content Procedimentos de amostragem e do modo de inserção no solo de sondas TDR na determinação da umidade volumétrica do solo

    Directory of Open Access Journals (Sweden)

    W. G. Teixeira

    2003-08-01

    Full Text Available Volumetric soil water content (theta can be evaluated in the field by direct or indirect methods. Among the direct, the gravimetric method is regarded as highly reliable and thus often preferred. Its main disadvantages are that sampling and laboratory procedures are labor intensive, and that the method is destructive, which makes resampling of a same point impossible. Recently, the time domain reflectometry (TDR technique has become a widely used indirect, non-destructive method to evaluate theta. In this study, evaluations of the apparent dielectric number of soils (epsilon and samplings for the gravimetrical determination of the volumetric soil water content (thetaGrav were carried out at four sites of a Xanthic Ferralsol in Manaus - Brazil. With the obtained epsilon values, theta was estimated using empirical equations (thetaTDR, and compared with thetaGrav derived from disturbed and undisturbed samples. The main objective of this study was the comparison of thetaTDR estimates of horizontally as well as vertically inserted probes with the thetaGrav values determined by disturbed and undisturbed samples. Results showed that thetaTDR estimates of vertically inserted probes and the average of horizontally measured layers were only slightly and insignificantly different. However, significant differences were found between the thetaTDR estimates of different equations and between disturbed and undisturbed samples in the thetaGrav determinations. The use of the theoretical Knight et al. model, which permits an evaluation of the soil volume assessed by TDR probes, is also discussed. It was concluded that the TDR technique, when properly calibrated, permits in situ, nondestructive measurements of q in Xanthic Ferralsols of similar accuracy as the gravimetric method.A umidade volumétrica do solo (teta no campo pode ser avaliada por métodos diretos e indiretos. Dentre os métodos diretos, o gravimétrico é considerado altamente confiável e, conseq

  19. Rapid volumetric imaging with Bessel-Beam three-photon microscopy

    Science.gov (United States)

    Chen, Bingying; Huang, Xiaoshuai; Gou, Dongzhou; Zeng, Jianzhi; Chen, Guoqing; Pang, Meijun; Hu, Yanhui; Zhao, Zhe; Zhang, Yunfeng; Zhou, Zhuan; Wu, Haitao; Cheng, Heping; Zhang, Zhigang; Xu, Chris; Li, Yulong; Chen, Liangyi; Wang, Aimin

    2018-01-01

    Owing to its tissue-penetration ability, multi-photon fluorescence microscopy allows for the high-resolution, non-invasive imaging of deep tissue in vivo; the recently developed three-photon microscopy (3PM) has extended the depth of high-resolution, non-invasive functional imaging of mouse brains to beyond 1.0 mm. However, the low repetition rate of femtosecond lasers that are normally used in 3PM limits the temporal resolution of point-scanning three-photon microscopy. To increase the volumetric imaging speed of 3PM, we propose a combination of an axially elongated needle-like Bessel-beam with three-photon excitation (3PE) to image biological samples with an extended depth of focus. We demonstrate the higher signal-to-background ratio (SBR) of the Bessel-beam 3PM compared to the two-photon version both theoretically and experimentally. Finally, we perform simultaneous calcium imaging of brain regions at different axial locations in live fruit flies and rapid volumetric imaging of neuronal structures in live mouse brains. These results highlight the unique advantage of conducting rapid volumetric imaging with a high SBR in the deep brain in vivo using scanning Bessel-3PM.

  20. Volumetric erosion rate reduction of Hall thruster channel wall during ion sputtering process

    International Nuclear Information System (INIS)

    Yu Daren; Li Yuquan

    2007-01-01

    The mechanisms of the volumetric erosion rate reduction of the channel wall were studied theoretically and numerically in order to explain the reasons why the volumetric erosion rate of Hall thruster channel decreases over time. The results of the theoretical analysis indicate that the variation of three sputtering conditions results from the increase in the tilt angle and the erosion depth of the channel wall erosion surface during the surface evolution process. The mass loss of the Hall thruster channel wall material is a reduction process due to which the ion flux divergent angle is smaller than the value that corresponds to the sufficient condition of the reduction process. The simulation results of the channel wall erosion process qualitatively agree well with the experimental results, and the numerical analysis of the reduction process shows that the magnitude orders of three sputtering condition variation effects on the volumetric erosion rate reduction are the same, and the reduction rate reaches its maximum value in the initial operation period when the ion radiation angle equals the optimum sputtering rate angle. This work provides theoretical fundamentals of the channel wall erosion reduction process and it can be used for the lifetime prediction and optimum design of the Hall thruster

  1. Experimental determination of thermal contact conductance between pressure and calandria tubes of Indian pressurised heavy water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Dureja, A.K., E-mail: akdureja@barc.gov.in [Reactor Design & Development Group, Bhabha Atomic Research Centre, Mumbai (India); Pawaskar, D.N.; Seshu, P. [Department of Mechanical Engineering, Indian Institute of Technology Bombay, Mumbai (India); Sinha, S.K. [Reactor Design & Development Group, Bhabha Atomic Research Centre, Mumbai (India); Sinha, R.K. [Department of Atomic Energy, OYC, Near Gateway of India, Mumbai (India)

    2015-04-01

    Highlights: • We established an experimental facility to measure thermal contact conductance between disc shaped specimens. • We measured thermal contact conductance between Zr-2.5Nb alloy pressure tube (PT) material and Zr-4 calandria tube (CT) material. • We concluded that thermal contact conductance is a linear function of contact pressure for interface of PT and CT up to 10 MPa contact pressure. • We concluded that thermal contact conductance is a weak function of interface temperature. - Abstract: Thermal contact conductance (TCC) is one of the most important parameters in determining the temperature distribution in contacting structures. Thermal contact conductance between the contacting structures depends on the mechanical properties of underlying materials, thermo-physical properties of the interstitial fluid and surface condition of the structures coming in contact. During a postulated accident scenario of loss of coolant with coincident loss of emergency core cooling system in a tube type heavy water nuclear reactor, the pressure tube is expected to sag/balloon and come in contact with outer cooler calandria tube to dissipate away the heat generated to the moderator. The amount of heat thus transferred is a function of thermal contact conductance and the nature of contact between the two tubes. An experimental facility was designed, fabricated and commissioned to measure thermal contact conductance between pressure tube and calandria tube specimens. Experiments were conducted on disc shaped specimens under axial contact pressure in between mandrels. Experimental results of TCC and a linear correlation as a function of contact pressure have been reported in this paper.

  2. Determination of ultra-short laser induced damage threshold of KH2PO4 crystal: Numerical calculation and experimental verification

    Directory of Open Access Journals (Sweden)

    Jian Cheng

    2016-03-01

    Full Text Available Rapid growth and ultra-precision machining of large-size KDP (KH2PO4 crystals with high laser damage resistance are tough challenges in the development of large laser systems. It is of high interest and practical significance to have theoretical models for scientists and manufacturers to determine the laser-induced damage threshold (LIDT of actually prepared KDP optics. Here, we numerically and experimentally investigate the laser-induced damage on KDP crystals in ultra-short pulse laser regime. On basis of the rate equation for free electron generation, a model dedicated to predicting the LIDT is developed by considering the synergistic effect of photoionization, impact ionization and decay of electrons. Laser damage tests are performed to measure the single-pulse LIDT with several testing protocols. The testing results combined with previously reported experimental data agree well with those calculated by the model. By taking the light intensification into consideration, the model is successfully applied to quantitatively evaluate the effect of surface flaws inevitably introduced in the preparation processes on the laser damage resistance of KDP crystals. This work can not only contribute to further understanding of the laser damage mechanisms of optical materials, but also provide available models for evaluating the laser damage resistance of exquisitely prepared optical components used in high power laser systems.

  3. Experimentally Determining β-Decay Intensities for 103,104Nb to Improve R-process Calculations

    Science.gov (United States)

    Gombas, J.; Deyoung, P. D.; Spyrou, A.; Dombos, A. C.; Lyons, S.; The SuN Collaboration

    2017-09-01

    The rapid neutron capture process (r-process) is responsible for the formation of nuclei heavier than iron. This process is theorized to occur in supernovas and/or neutron star mergers. R-process calculations require the accurate knowledge of a significant amount of nuclear properties, the majority of which are not known experimentally. Nuclear masses, β-decay properties and neutron-capture reactions are all input ingredients into r-process models. This present study focuses on the β decay of 103Nb and 104Nb. The β decay of 103Nb and 104Nb, two nuclei found in the r-process, were observed at the NSCL using the Summing NaI (SuN) detector. An unstable beam implanted inside SuN. The γ rays were measured in coincidence with the emitted electrons. The β-decay intensity function was then extracted. The experimentally determined functions for 103Nb and 104Nb will be compared to predictions made by the Quasi Random Phase Approximation (QRPA) model. These theoretical calculations are used in astrophysical models of the r-process. This comparison will lead to a better understanding of the nuclear structure for 103Nb and 104Nb. A more dependable prediction of the formation of heavier nuclei birthed from supernovas or neutron star mergers can then be made. This material is based upon work supported by the National Science Foundation under Grant No. PHY-1613188 and PHY-1306074, and by the Hope College Department of Physics Guess Research Fund.

  4. Experimental Determination of the Molar Absorption Coefficient of n-Hexane Adsorbed on High-Silica Zeolites.

    Science.gov (United States)

    Gatti, Giorgio; Olivas Olivera, Diana F; Sacchetto, Vittoria; Cossi, Maurizio; Braschi, Ilaria; Marchese, Leonardo; Bisio, Chiara

    2017-09-06

    Determination of the molar absorption coefficients of the CH 3 bending mode at ν˜ =1380 cm -1 (ϵ 1380 ) of n-hexane adsorbed from the gas phase on two different dealuminated zeolites is derived by a combination of IR spectroscopy and microgravimetric analysis. High-silica zeolite Y (HSZ-Y) and zeolite ZSM-5 (with SiO 2 /Al 2 O 3 ratios of 200 and 280, respectively) with different textural and surface features are selected to evaluate the effect of the pore structure and architecture on the value of ϵ 1380 of the adsorbed n-hexane. Experimental data indicate that the molecule experiences a different adsorption environment inside zeolites; thus resulting in a significant change of the dipole moment and very different ϵ 1380 values: (0.278±0.018) cm μmol -1 for HSZ-Y and (0.491±0.032) cm μmol -1 for ZSM-5. Experimental data are also supported by computational modeling, which confirms the effect of different matrices on the IR absorption intensity. This study reveals that the use of probe molecules for quantitative measurements of surface sites has to be judiciously adopted, especially if adsorption occurs in the restricted spaces of microporous materials. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Contact-free experimental determination of the static flexural spring constant of cantilever sensors using a microfluidic force tool.

    Science.gov (United States)

    Parkin, John D; Hähner, Georg

    2016-01-01

    Micro- and nanocantilevers are employed in atomic force microscopy (AFM) and in micro- and nanoelectromechanical systems (MEMS and NEMS) as sensing elements. They enable nanomechanical measurements, are essential for the characterization of nanomaterials, and form an integral part of many nanoscale devices. Despite the fact that numerous methods described in the literature can be applied to determine the static flexural spring constant of micro- and nanocantilever sensors, experimental techniques that do not require contact between the sensor and a surface at some point during the calibration process are still the exception rather than the rule. We describe a noncontact method using a microfluidic force tool that produces accurate forces and demonstrate that this, in combination with a thermal noise spectrum, can provide the static flexural spring constant for cantilever sensors of different geometric shapes over a wide range of spring constant values (≈0.8-160 N/m).

  6. Experimental determination of temperature fields in sodium-cooled rod bundles with hexagonal rod arrangement and grid spacers

    International Nuclear Information System (INIS)

    Moeller, R.; Tschoeke, H.; Kolodziej, M.

    1977-01-01

    Three-dimensional temperature fields in the claddings of sodium cooled rods were determined experimentally under representative nominal operating conditions for a SNR typical 19-rod bundle model provided with spark-eroded spacers. These experiments are required to verify thermohydraulic computer programs which will provide the output data for strength calculations of the high loaded cladding tubes. In this work the essentials are reported of the measured circumferential distributions of wall temperatures of peripheral rods. In addition the sub-channel temperatures measured over the bundle cross section are indicated, they are required to sustain codes for the global thermohydraulic design of core elements. The most important results are: 1) The whole fuel element is located within the thermal entrance length. 2) High azimuthal temperature differences were measured in the claddings of peripheral rods, which are strongly influenced by the distance between the rod and the shroud, especially for the corner rod. 3) With decreasing Pe-number ( [de

  7. New experimental set up for the determination of the ratio gA/gV from a cold neutron beam

    International Nuclear Information System (INIS)

    Avenier, Michel.

    1976-01-01

    A new experimental set up is being developed for an improved measurement of the electron momentum-neutron spin angular correlation coefficient A, in polarized free neutron beta decay, in order to determine with a greater accuracy the ratio gA/gV of the coupling constants of the weak interaction. With the institut Laue-Langevin high flux beam facilities it seems unnecessary to register the electrons in coincidence with the recoil protons as in previous experiments. Two beta counters will be symetrically placed about the beam and, by flipping periodically the beam polarization and defining the geometry of the experiment such as to minimize the backscattering, the accuracy of the measurement could be better than 5% which would correspond to an accuracy of [fr

  8. Determining the representative volume element size for three-dimensional microstructural material characterization. Part 2: Application to experimental data

    Science.gov (United States)

    Harris, William M.; Chiu, Wilson K. S.

    2015-05-01

    Improved microstructural imaging and characterization methods have recently opened the door for quantitative evaluation of microstructures of such functional materials as solid oxide fuel cell and battery electrodes and composite gas separation membranes. Accurate quantitative characterization of these structures relies on the concept of a representative volume element (RVE) to provide a sufficiently large sample to be statistically representative of the material. In Part 1 of this work, several models were described to determine the RVE size for several common microstructural properties: volume fraction, particle size, and network contiguity. In this work, extensive synchrotron X-ray nanotomography imaging of a multiphase composite gas separation membrane is used to provide an experimental comparison to the model predictions. Results suggest that the models provide a reasonable estimate of RVE size, and can serve as a starting point for researchers planning imaging and characterization experiments.

  9. Contact-free experimental determination of the static flexural spring constant of cantilever sensors using a microfluidic force tool

    Directory of Open Access Journals (Sweden)

    John D. Parkin

    2016-03-01

    Full Text Available Micro- and nanocantilevers are employed in atomic force microscopy (AFM and in micro- and nanoelectromechanical systems (MEMS and NEMS as sensing elements. They enable nanomechanical measurements, are essential for the characterization of nanomaterials, and form an integral part of many nanoscale devices. Despite the fact that numerous methods described in the literature can be applied to determine the static flexural spring constant of micro- and nanocantilever sensors, experimental techniques that do not require contact between the sensor and a surface at some point during the calibration process are still the exception rather than the rule. We describe a noncontact method using a microfluidic force tool that produces accurate forces and demonstrate that this, in combination with a thermal noise spectrum, can provide the static flexural spring constant for cantilever sensors of different geometric shapes over a wide range of spring constant values (≈0.8–160 N/m.

  10. On-line CO, CO2 emissions evaluation and (benzene, toluene, xylene) determination from experimental burn of tropical biomass.

    Science.gov (United States)

    Tawfiq, Mohammed F; Aroua, Mohamed Kheireddine; Sulaiman, Nik Meriam Nik

    2015-07-01

    Atmospheric pollution and global warming issues are increasingly becoming major environmental concerns. Fire is one of the significant sources of pollutant gases released into the atmosphere; and tropical biomass fires, which are of particular interest in this study, contribute greatly to the global budget of CO and CO2. This pioneer research simulates the natural biomass burning strategy in Malaysia using an experimental burning facility. The investigation was conducted on the emissions (CO2, CO, and Benzene, Toluene, Ethylbenzene, Xylenes (BTEX)) from ten tropical biomass species. The selected species represent the major tropical forests that are frequently subjected to dry forest fire incidents. An experimental burning facility equipped with an on-line gas analyzer was employed to determine the burning emissions. The major emission factors were found to vary among the species, and the specific results were as follows. The moisture content of a particular biomass greatly influenced its emission pattern. The smoke analysis results revealed the existence of BTEX, which were sampled from a combustion chamber by enrichment traps aided with a universal gas sampler. The BTEX were determined by organic solvent extraction followed by GC/MS quantification, the results of which suggested that the biomass burning emission factor contributed significant amounts of benzene, toluene, and m,p-xylene. The modified combustion efficiency (MCE) changed in response to changes in the sample moisture content. Therefore, this study concluded that the emission of some pollutants mainly depends on the burning phase and sample moisture content of the biomass. Copyright © 2015. Published by Elsevier B.V.

  11. Experimental determination of the phase relations of the Sm–Fe–B ternary system at 973 K

    Energy Technology Data Exchange (ETDEWEB)

    Xu, CH.F. [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); School of Mechanical Engineering, Guilin University of Aerospace Technology, Guilin 541004, Guangxi (China); School of Material Science and Engineering, Guilin University of Electronic Technology, Guilin, Guangxi (China); Chen, K.H., E-mail: khchen@csu.edu.cn [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Gu, Z.F.; Ma, D.D.; Cheng, L.Y.; Cheng, G.; Rao, G.H. [School of Material Science and Engineering, Guilin University of Electronic Technology, Guilin, Guangxi (China)

    2016-05-15

    The phase relations of the Sm–Fe–B ternary system at 973 K have been determined experimentally in this study by X-ray diffraction, scanning electron microscopy and energy dispersion spectroscopy techniques. This tentative isothermal section includes 15 single-phase regions, 30 two-phase regions, and 16 three-phase regions. The phases αFe{sub 17}Sm{sub 2}, Fe{sub 3}Sm, Fe{sub 2}Sm, Sm{sub 2}B{sub 5}, SmB{sub 4}, SmB{sub 6}, SmB{sub 66}, Fe{sub 2}B and FeB are confirmed to exist at 973 K. The existence of the only three ternary phases Sm{sub 2}Fe{sub 14}B, SmFeB{sub 4} and Sm{sub 17}(Fe{sub 4}B{sub 4}){sub 15} is observed. - Highlights: • The αFe{sub 17}Sm{sub 2}, Fe{sub 3}Sm, Fe{sub 2}Sm, Sm{sub 2}B{sub 5}, SmB{sub 4}, SmB{sub 6}, SmB{sub 66}, Fe{sub 2}B and FeB exist at 973 K. • The existence of the phases Sm{sub 2}Fe{sub 14}B, SmFeB{sub 4} and Sm{sub 17}(Fe{sub 4}B{sub 4}){sub 15} is observed at 973 K. • The isothermal section of the Sm–Fe–B system at 973 K is determined experimentally.

  12. Increasing the volumetric efficiency of Diesel engines by intake pipes

    Science.gov (United States)

    List, Hans

    1933-01-01

    Development of a method for calculating the volumetric efficiency of piston engines with intake pipes. Application of this method to the scavenging pumps of two-stroke-cycle engines with crankcase scavenging and to four-stroke-cycle engines. The utility of the method is demonstrated by volumetric-efficiency tests of the two-stroke-cycle engines with crankcase scavenging. Its practical application to the calculation of intake pipes is illustrated by example.

  13. A Technique for Volumetric CSG Based on Morphology

    DEFF Research Database (Denmark)

    Bærentzen, Jakob Andreas; Christensen, Niels Jørgen

    2001-01-01

    In this paper, a new technique for volumetric CSG is presented. The technique requires the input volumes to correspond to solids which fulfill a voxelization suitability criterion. Assume the CSG operation is union. The volumetric union of two such volumes is defined in terms of the voxelization...... of the union of the two original solids. The theory behind the new technique is discussed, the algorithm and implementation are presented. Finally, we present images and timings....

  14. A comparison of semi-automated volumetric vs linear measurement of small vestibular schwannomas.

    Science.gov (United States)

    MacKeith, Samuel; Das, Tilak; Graves, Martin; Patterson, Andrew; Donnelly, Neil; Mannion, Richard; Axon, Patrick; Tysome, James

    2018-04-01

    Accurate and precise measurement of vestibular schwannoma (VS) size is key to clinical management decisions. Linear measurements are used in routine clinical practice but are prone to measurement error. This study aims to compare a semi-automated volume segmentation tool against standard linear method for measuring small VS. This study also examines whether oblique tumour orientation can contribute to linear measurement error. Experimental comparison of observer agreement using two measurement techniques. Tertiary skull base unit. Twenty-four patients with unilateral sporadic small (linear dimension following reformatting to correct for oblique orientation of VS. Intra-observer ICC was higher for semi-automated volumetric when compared with linear measurements, 0.998 (95% CI 0.994-0.999) vs 0.936 (95% CI 0.856-0.972), p linear measurements, 0.989 (95% CI 0.975-0.995) vs 0.946 (95% CI 0.880-0.976), p = 0.0045. The intra-observer %SDD was similar for volumetric and linear measurements, 9.9% vs 11.8%. However, the inter-observer %SDD was greater for volumetric than linear measurements, 20.1% vs 10.6%. Following oblique reformatting to correct tumour angulation, the mean increase in size was 1.14 mm (p = 0.04). Semi-automated volumetric measurements are more repeatable than linear measurements when measuring small VS and should be considered for use in clinical practice. Oblique orientation of VS may contribute to linear measurement error.

  15. Volumetric graphics in liquid using holographic femtosecond laser pulse excitations

    Science.gov (United States)

    Kumagai, Kota; Hayasaki, Yoshio

    2017-06-01

    Much attention has been paid to the development of three-dimensional volumetric displays in the fields of optics and computer graphics, and it is a dream of we display researchers. However, full-color volumetric displays are challenging because many voxels with different colors have to be formed to render volumetric graphics in real three-dimensional space. Here, we show a new volumetric display in which microbubble voxels are three-dimensionally generated in a liquid by focused femtosecond laser pulses. Use of a high-viscosity liquid, which is the key idea of this system, slows down the movement of the microbubbles, and as a result, volumetric graphics can be displayed. This "volumetric bubble display" has a wide viewing angle and simple refresh and requires no addressing wires because it involves optical access to transparent liquid and achieves full-color graphics composed on light-scattering voxels controlled by illumination light sources. In addition, a bursting of bubble graphics system using an ultrasonic vibrator also has been demonstrated. This technology will open up a wide range of applications in three-dimensional displays, augmented reality and computer graphics.

  16. Subcortical volumetric abnormalities in bipolar disorder.

    Science.gov (United States)

    Hibar, D P; Westlye, L T; van Erp, T G M; Rasmussen, J; Leonardo, C D; Faskowitz, J; Haukvik, U K; Hartberg, C B; Doan, N T; Agartz, I; Dale, A M; Gruber, O; Krämer, B; Trost, S; Liberg, B; Abé, C; Ekman, C J; Ingvar, M; Landén, M; Fears, S C; Freimer, N B; Bearden, C E; Sprooten, E; Glahn, D C; Pearlson, G D; Emsell, L; Kenney, J; Scanlon, C; McDonald, C; Cannon, D M; Almeida, J; Versace, A; Caseras, X; Lawrence, N S; Phillips, M L; Dima, D; Delvecchio, G; Frangou, S; Satterthwaite, T D; Wolf, D; Houenou, J; Henry, C; Malt, U F; Bøen, E; Elvsåshagen, T; Young, A H; Lloyd, A J; Goodwin, G M; Mackay, C E; Bourne, C; Bilderbeck, A; Abramovic, L; Boks, M P; van Haren, N E M; Ophoff, R A; Kahn, R S; Bauer, M; Pfennig, A; Alda, M; Hajek, T; Mwangi, B; Soares, J C; Nickson, T; Dimitrova, R; Sussmann, J E; Hagenaars, S; Whalley, H C; McIntosh, A M; Thompson, P M; Andreassen, O A

    2016-12-01

    Considerable uncertainty exists about the defining brain changes associated with bipolar disorder (BD). Understanding and quantifying the sources of uncertainty can help generate novel clinical hypotheses about etiology and assist in the development of biomarkers for indexing disease progression and prognosis. Here we were interested in quantifying case-control differences in intracranial volume (ICV) and each of eight subcortical brain measures: nucleus accumbens, amygdala, caudate, hippocampus, globus pallidus, putamen, thalamus, lateral ventricles. In a large study of 1710 BD patients and 2594 healthy controls, we found consistent volumetric reductions in BD patients for mean hippocampus (Cohen's d=-0.232; P=3.50 × 10 -7 ) and thalamus (d=-0.148; P=4.27 × 10 -3 ) and enlarged lateral ventricles (d=-0.260; P=3.93 × 10 -5 ) in patients. No significant effect of age at illness onset was detected. Stratifying patients based on clinical subtype (BD type I or type II) revealed that BDI patients had significantly larger lateral ventricles and smaller hippocampus and amygdala than controls. However, when comparing BDI and BDII patients directly, we did not detect any significant differences in brain volume. This likely represents similar etiology between BD subtype classifications. Exploratory analyses revealed significantly larger thalamic volumes in patients taking lithium compared with patients not taking lithium. We detected no significant differences between BDII patients and controls in the largest such comparison to date. Findings in this study should be interpreted with caution and with careful consideration of the limitations inherent to meta-analyzed neuroimaging comparisons.

  17. Volumetric optoacoustic monitoring of endovenous laser treatments

    Science.gov (United States)

    Fehm, Thomas F.; Deán-Ben, Xosé L.; Schaur, Peter; Sroka, Ronald; Razansky, Daniel

    2016-03-01

    Chronic venous insufficiency (CVI) is one of the most common medical conditions with reported prevalence estimates as high as 30% in the adult population. Although conservative management with compression therapy may improve the symptoms associated with CVI, healing often demands invasive procedures. Besides established surgical methods like vein stripping or bypassing, endovenous laser therapy (ELT) emerged as a promising novel treatment option during the last 15 years offering multiple advantages such as less pain and faster recovery. Much of the treatment success hereby depends on monitoring of the treatment progression using clinical imaging modalities such as Doppler ultrasound. The latter however do not provide sufficient contrast, spatial resolution and three-dimensional imaging capacity which is necessary for accurate online lesion assessment during treatment. As a consequence, incidence of recanalization, lack of vessel occlusion and collateral damage remains highly variable among patients. In this study, we examined the capacity of volumetric optoacoustic tomography (VOT) for real-time monitoring of ELT using an ex-vivo ox foot model. ELT was performed on subcutaneous veins while optoacoustic signals were acquired and reconstructed in real-time and at a spatial resolution in the order of 200μm. VOT images showed spatio-temporal maps of the lesion progression, characteristics of the vessel wall, and position of the ablation fiber's tip during the pull back. It was also possible to correlate the images with the temperature elevation measured in the area adjacent to the ablation spot. We conclude that VOT is a promising tool for providing online feedback during endovenous laser therapy.

  18. Real-time volumetric scintillation dosimetry

    Science.gov (United States)

    Beddar, S.

    2015-01-01

    The goal of this brief review is to review the current status of real-time 3D scintillation dosimetry and what has been done so far in this area. The basic concept is to use a large volume of a scintillator material (liquid or solid) to measure or image the dose distributions from external radiation therapy (RT) beams in three dimensions. In this configuration, the scintillator material fulfills the dual role of being the detector and the phantom material in which the measurements are being performed. In this case, dose perturbations caused by the introduction of a detector within a phantom will not be at issue. All the detector configurations that have been conceived to date used a Charge-Coupled Device (CCD) camera to measure the light produced within the scintillator. In order to accurately measure the scintillation light, one must correct for various optical artefacts that arise as the light propagates from the scintillating centers through the optical chain to the CCD chip. Quenching, defined in its simplest form as a nonlinear response to high-linear energy transfer (LET) charged particles, is one of the disadvantages when such systems are used to measure the absorbed dose from high-LET particles such protons. However, correction methods that restore the linear dose response through the whole proton range have been proven to be effective for both liquid and plastic scintillators. Volumetric scintillation dosimetry has the potential to provide fast, high-resolution and accurate 3D imaging of RT dose distributions. Further research is warranted to optimize the necessary image reconstruction methods and optical corrections needed to achieve its full potential.

  19. Use of experimentally determined Henry's Law and salting-out constants for ethanol in seawater for determination of the saturation state of ethanol in coastal waters.

    Science.gov (United States)

    Willey, Joan D; Powell, Jacqueline P; Avery, G Brooks; Kieber, Robert J; Mead, Ralph N

    2017-09-01

    The Henry's law constant for ethanol in seawater was experimentally determined to be 221 ± 4 M/atm at 22 °C compared with 247 ± 6 M/atm in pure water. The salting out coefficient for ethanol was 0.13 M -1 . In seawater ln(K H ) = -(12.8 ± 0.7) + (5310 ± 197)/T where K H is in M atm -1 and temperature is in K. This plus the salting out coefficient allow calculation of K H for any estuarine or sea water between 1 and 35 °C. High concentrations of dissolved organic carbon do not affect K H values in fresh or seawater. Nearshore surface waters were usually undersaturated with respect to gas phase ethanol except when air concentrations decreased, whereas surface seawater 40 km from shore was supersaturated. The percent saturation in surface waters is driven primarily by changes in air concentrations because these change quickly (hours) and more extensively than surface water. This study allows calculation of ethanol saturation states from air and surface water concentrations which is a necessary step to define the role of surface oceans in the global biogeochemical cycling of ethanol both now and in the future as use of ethanol biofuel continues to grow. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Language Lateralization in Patients with Temporal Lobe Epilepsy : A Comparison between Volumetric Analysis and the Wada Test.

    Science.gov (United States)

    Oh, Young-Min; Koh, Eun-Jeong

    2009-06-01

    Determining language lateralization is important for the presurgical evaluation of patients with medically intractable epilepsy. The Wada test has been the gold standard for lateralization of language dominance before epilepsy surgery. However, it is an invasive test with risk, and have some limitations. We compared the volumetric analysis with Wada test, and studied the clinical potential of volumetric analysis to assess language laterality in large surgical candidates with temporal lobe epilepsy (TLE). To examine the efficacy of volumetric analysis to determine language lateralization during presurgical evaluation, we compared the volumetric analysis of the bilateral planum temporale with the results of Wada test in 59 patients with chronic intractable TLE (rTLE, n=32; lTLE, n=27) who underwent epilepsy surgery. We measured the gray matter volumes of planum temporale (PT) of each patients using the VoxelPlus2 program (Mevisys, Daejeon, Korea). Overall congruence of the volumetric analysis with the Wada test was 97.75% in rTLE patients and 81.5% in lTLE patients. There were more significant leftward asymmetry of the PT in rTLE patients than lTLE patients. In lTLE patients, relatively high proportion (37%) of the patients showed bilateral or right hemispheric language dominance. These results provide evidence that the volumetric analysis of the PT could be used as an alternatives in language lateralization. Also, the results of the Wada test suggested that there was considerable plasticity of language representation in the brains of patients with intractable TLE and it was associated with an earlier age of brain injury.

  1. The Effect of Elevation on Volumetric Measurements of the Lower Extremity

    Directory of Open Access Journals (Sweden)

    Cordial M. Gillette

    2017-07-01

    Full Text Available Background: The empirical evidence for the use of RICE (rest, ice, compression, elevation has been questioned regarding its   clinical effectiveness. The component of RICE that has the least literature regarding its effectiveness is elevation. Objective: The objective of this study was to determine if various positions of elevation result in volumetric changes of the lower extremity. Methodology: A randomized crossover design was used to determine the effects of the four following conditions on volumetric changes of the lower extremity: seated at the end of a table (seated, lying supine (flat, lying supine with the foot elevated 12 inches off the table (elevated, and lying prone with the knees bent to 90 degrees (prone. The conditions were randomized using a Latin Square. Each subject completed all conditions with at least 24 hours between each session. Pre and post volumetric measurements were taken using a volumetric tank. The subject was placed in one of the four described testing positions for 30 minutes. The change in weight of the displaced water was the main outcome measure. The data was analyzed using an ANOVA of the pre and post measurements with a Bonferroni post hoc analysis. The level of significance was set at P<.05 for all analyses. Results: The only statistically significant difference was between the gravity dependent position (seated and all other positions (p <.001. There was no significant difference between lying supine (flat, on a bolster (elevated, or prone with the knees flexed to 90 degrees (prone. Conclusions: From these results, the extent of elevation does not appear to have an effect on changes in low leg volume. Elevation above the heart did not significantly improve reduction in limb volume, but removing the limb from a gravity dependent position might be beneficial.

  2. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis

    Directory of Open Access Journals (Sweden)

    Ana María Camacho

    2016-09-01

    Full Text Available Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS2 grease, silicone oil, and copper paste to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs. The results show that for small reductions (rh < 20%, the conventional RCT can be applied because the tribological conditions remain similar. For large reductions (rh > 20%, it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered.

  3. Experimental and numerical determination of critical stress intensity factor of aluminum curved thin sheets under tensile stress

    Energy Technology Data Exchange (ETDEWEB)

    Heidarvand, Majid; Soltani, Naser; Hajializadeh, Farshid [University of Tehran, Tehran (Iran, Islamic Republic of)

    2017-05-15

    We determined the fracture toughness of aluminum curved thin sheets using tensile stress tests and finite element method. We applied Linear elastic fracture mechanics (LEFM) and Feddersen procedure to evaluate stress intensity factor of the samples with central wire-cut cracks and fatigue cracks with different lengths to investigate the notch radius effect. Special fixture design was utilized to establish uniform stress distribution at the crack zone. Less than 9 % difference was found between the wire-cut and the fatigue cracked samples. Since generating central fatigue crack with different lengths required so much effort, wire-cut cracked samples were used to determine critical stress intensity factor. Finite element analysis was also performed on one-quarter of the specimen using both the singular Borsum elements and the regular isoparametric elements to further investigate fracture toughness of the samples. It was observed that the singular elements presented better results than the isoparametric ones. A slight difference was also found between the results obtained from finite element method using singular elements and the experimental results.

  4. Zirconium and Yttrium (p, d) Surrogate Nuclear Reactions: Measurement and determination of gamma-ray probabilities: Experimental Physics Report

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J. T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hughes, R. O. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Escher, J. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Scielzo, N. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Casperson, R. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ressler, J. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Saastamoinen, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ota, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Park, H. I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ross, T. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McCleskey, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McCleskey, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Austin, R. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rapisarda, G. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-21

    This technical report documents the surrogate reaction method and experimental results used to determine the desired neutron induced cross sections of 87Y(n,g) and the known 90Zr(n,g) cross section. This experiment was performed at the STARLiTeR apparatus located at Texas A&M Cyclotron Institute using the K150 Cyclotron which produced a 28.56 MeV proton beam. The proton beam impinged on Y and Zr targets to produce the nuclear reactions 89Y(p,d)88Y and 92Zr(p,d)91Zr. Both particle singles data and particle-gamma ray coincident data were measured during the experiment. This data was used to determine the γ-ray probability as a function of energy for these reactions. The results for the γ-ray probabilities as a function of energy for both these nuclei are documented here. For completeness, extensive tabulated and graphical results are provided in the appendices.

  5. Experimental and Monte Carlo-based determination of the beam quality specifier for TomoTherapyHD treatment units.

    Science.gov (United States)

    Howitz, S; Schwedas, M; Wiezorek, T; Zink, K

    2017-10-12

    Reference dosimetry by means of clinical linear accelerators in high-energy photon fields requires the determination of the beam quality specifier TPR 20,10 , which characterizes the relative particle flux density of the photon beam. The measurement of TPR 20,10 has to be performed in homogenous photon beams of size 10×10cm 2 with a focus-detector distance of 100cm. These requirements cannot be fulfilled by TomoTherapy treatment units from Accuray. The TomoTherapy unit provides a flattening-filter-free photon fan beam with a maximum field width of 40cm and field lengths of 1.0cm, 2.5cm and 5.0cm at a focus-isocenter distance of 85cm. For the determination of the beam quality specifier from measurements under nonstandard reference conditions Sauer and Palmans proposed experiment-based fit functions. Moreover, Sauer recommends considering the impact of the flattening-filter-free beam on the measured data. To verify these fit functions, in the present study a Monte Carlo based model of the treatment head of a TomoTherapyHD unit was designed and commissioned with existing beam data of our clinical TomoTherapy machine. Depth dose curves and dose profiles were in agreement within 1.5% between experimental and Monte Carlo-based data. Based on the fit functions from Sauer and Palmans the beam quality specifier TPR 20,10 was determined from field sizes 5×5cm 2 , 10×5cm 2 , 20×5cm 2 and 40×5cm 2 based on dosimetric measurements and Monte Carlo simulations. The mean value from all experimental values of TPR 20,10 resulted in TPR 20,10 ¯=0.635±0.4%. The impact of the non-homogenous field due to the flattening-filter-free beam was negligible for field sizes below 20×5cm 2 . The beam quality specifier calculated by Monte Carlo simulations was TPR 20,10 =0.628 and TPR 20,10 =0.631 for two different calculation methods. The stopping power ratio water-to-air s w,a Δ directly depends on the beam quality specifier. The value determined from all experimental TPR 20,10 data

  6. Normative biometrics for fetal ocular growth using volumetric MRI reconstruction.

    Science.gov (United States)

    Velasco-Annis, Clemente; Gholipour, Ali; Afacan, Onur; Prabhu, Sanjay P; Estroff, Judy A; Warfield, Simon K

    2015-04-01

    To determine normative ranges for fetal ocular biometrics between 19 and 38 weeks gestational age (GA) using volumetric MRI reconstruction. The 3D images of 114 healthy fetuses between 19 and 38 weeks GA were created using super-resolution volume reconstructions from MRI slice acquisitions. These 3D images were semi-automatically segmented to measure fetal orbit volume, binocular distance (BOD), interocular distance (IOD), and ocular diameter (OD). All biometry correlated with GA (Volume, Pearson's correlation coefficient (CC) = 0.9680; BOD, CC = 0.9552; OD, CC = 0.9445; and IOD, CC = 0.8429), and growth curves were plotted against linear and quadratic growth models. Regression analysis showed quadratic models to best fit BOD, IOD, and OD and a linear model to best fit volume. Orbital volume had the greatest correlation with GA, although BOD and OD also showed strong correlation. The normative data found in this study may be helpful for the detection of congenital fetal anomalies with more consistent measurements than are currently available. © 2015 John Wiley & Sons, Ltd. © 2015 John Wiley & Sons, Ltd.

  7. Volumetric PIV in Patient-Specific Cerebral Aneurysm

    Science.gov (United States)

    Brindise, Melissa; Dickerhoff, Ben; Saloner, David; Rayz, Vitaliy; Vlachos, Pavlos

    2016-11-01

    Cerebral aneurysms impose a unique challenge in which neurosurgeons must assess and decide between the risk of rupture and risk of treatment for each patient. Risk of rupture is often difficult to determine and most commonly assessed using geometric data including the size and shape of the aneurysm and parent vessel. Hemodynamics is thought to play a major role in the growth and rupture of a cerebral aneurysm, but its specific influence is largely unknown due to the inability of in vivo modalities to characterize detailed flow fields and limited in vitro studies. In this work, we use a patient-specific basilar tip aneurysm model and volumetric particle image velocimetry (PIV). In vivo, 4-D PC-MRI measurements were obtained for this aneurysm and the extracted pulsatile waveform was used for the in vitro study. Clinically relevant metrics including wall shear stress (WSS), oscillatory shear index (OSI), relative residence time (RRT), 3-D pressure contours, and pressure wave speed were subsequently computed. This is the first study to investigate in vitro 3-D pressure fields within a cerebral aneurysm. The results of this study demonstrate how these metrics influence the biomechanics of the aneurysm and ultimately their affect on the risk of rupture.

  8. Experimental and simulation determination of minimum miscibility pressure for a Bakken tight oil and different injection gases

    Directory of Open Access Journals (Sweden)

    Sheng Li

    2017-03-01

    Full Text Available The effective development of unconventional tight oil formations, such as Bakken, could include CO2 enhanced oil recovery (EOR technologies with associated benefits of capturing and storing large quantities of CO2. It is important to conduct the gas injection at miscible condition so as to reach maximum recovery efficiency. Therefore, determination of the minimum miscibility pressure (MMP of reservoir live oil–injection gas system is critical in a miscible gas flooding project design. In this work, five candidate injection gases, namely CO2, CO2-enriched flue gas, natural gas, nitrogen, and CO2-enriched natural gas, were selected and their MMPs with a Bakken live oil were determined experimentally and numerically. At first, phase behaviour tests were conducted for the reconstituted Bakken live oil and the gases. CO2 outperformed other gases in terms of viscosity reduction and oil swelling. Rising bubble apparatus (RBA determined live oil–CO2 MMP as 11.9 MPa and all other gases higher than 30 MPa. The measured phase behaviour data were used to build and tune an equation-of-state (EOS model, which calculated the MMPs for different live oil-gas systems. The EOS-based calculations indicated that CO2 had the lowest MMP with live oil among the five gases in the study. At last, the commonly-accepted Alston et al. equation was used to calculate live oil–pure CO2 MMP and effect of impurities in the gas phase on MMP change. The Bakken oil–CO2 had a calculated MMP of 10.3 MPa from the Alston equation, and sensitivity analysis showed that slight addition of volatile impurities, particularly N2, can increase MMP significantly.

  9. Theoretical and experimental determination of dosimetric characteristics for brachyseedTM Pd-103, model Pd-1, source

    International Nuclear Information System (INIS)

    Meigooni, A.S.; Zhang Hualin; Perry, Candace; Dini, S.A.; Koona, R.A.

    2003-01-01

    Dosimetric characteristics of the BrachySeed TM Pd-103, Model Pd-1 source have been determined using both theoretical and experimental methods. Dose rate constant, radial dose function, and anisotropy functions of the source have been obtained following the TG-43 recommendations. Derivation of the dose rate constant was based on recent NIST WAFAC calibration performed in accordance with their 1999 Standard. Measurements were performed in Solid Water TM using LiF TLD chips. Theoretical simulation calculations were performed in both Solid Water TM and water phantom materials using MCNP4C2 Monte Carlo code using DLC-200 interaction data. The results of the Monte Carlo simulation indicated a dose rate constant of 0.65 cGy h -1 U -1 and 0.61 cGy h -1 U -1 in water and Solid Water TM , respectively. The measured dose rate constant in Solid Water TM was found to be 0.63±7% cGy h -1 U -1 , which is within the experimental uncertainty of the Monte-Carlo simulated results. The anisotropy functions of the source were calculated in both water and in Solid Water TM at the radial distances of 1 to 7 cm. Measurements were made in Solid Water TM at distances of 2, 3, 5, and 7 cm. The Monte-Carlo calculated anisotropy constant of the new source was found to be 0.98 in water. The tabulated data and 5th order polynomial fit coefficients for the radial dose function along with the dose rate constant and anisotropy functions are provided to support clinical use of this source

  10. Recommended volumetric capacity definitions and protocols for accurate, standardized and unambiguous metrics for hydrogen storage materials

    Science.gov (United States)

    Parilla, Philip A.; Gross, Karl; Hurst, Katherine; Gennett, Thomas

    2016-03-01

    The ultimate goal of the hydrogen economy is the development of hydrogen storage systems that meet or exceed the US DOE's goals for onboard storage in hydrogen-powered vehicles. In order to develop new materials to meet these goals, it is extremely critical to accurately, uniformly and precisely measure materials' properties relevant to the specific goals. Without this assurance, such measurements are not reliable and, therefore, do not provide a benefit toward the work at hand. In particular, capacity measurements for hydrogen storage materials must be based on valid and accurate results to ensure proper identification of promising materials for further development. Volumetric capacity determinations are becoming increasingly important for identifying promising materials, yet there exists controversy on how such determinations are made and whether such determinations are valid due to differing methodologies to count the hydrogen content. These issues are discussed herein, and we show mathematically that capacity determinations can be made rigorously and unambiguously if the constituent volumes are well defined and measurable in practice. It is widely accepted that this occurs for excess capacity determinations and we show here that this can happen for the total capacity determination. Because the adsorption volume is undefined, the absolute capacity determination remains imprecise. Furthermore, we show that there is a direct relationship between determining the respective capacities and the calibration constants used for the manometric and gravimetric techniques. Several suggested volumetric capacity figure-of-merits are defined, discussed and reporting requirements recommended. Finally, an example is provided to illustrate these protocols and concepts.

  11. Experimental determinations of carcass processing by Plio-Pleistocene hominids and carnivores at FLK 22 (Zinjanthropus). Olduvai Gorge, Tanzania.

    Science.gov (United States)

    Capaldo, S D

    1997-11-01

    Published and unpublished skeletal and surface mark data from the large, well-preserved, bovid dominated FLK 22 (Zinjanthropus) archaeofauna are analyzed using data derived from four different experimental control samples. The control samples are realistic because they are based on natural history and paleoecological data collected from FLK 22, and other Olduvai Gorge assemblages; they are precise because independent experimental studies following the same methods have generated the same results; and they restore generality to the study of site formation because each one models a different hominid and/or carnivore scenario of site formation. Comparability between FLK 22 and the control samples is established by excluding specimens from the former which do not meet identification and reporting standards derived from the latter. As in two previous studies, a comprehensive analysis of tooth marks and tool marks on long bone specimens from FLK 22 indicates that they were processed in three stages. In stage one, carnivores defleshed long bones, as inferred from the high percentage of tooth marks on midshaft fragments. In stage two, hominids processed intact long bones for marrow, as inferred from percussion mark percentages. Cut marks suggest that long bones retained flesh, but the amount, as yet, cannot be determined using cut mark percentages. In stage three, carnivores processed long bone epiphyses for grease, as inferred from the under-representation of long bone epiphyses and the high percentage of tooth marks on near-epiphyses and surviving epiphyses. The lack of comprehensive skeletal and surface mark data on cranial, axial, compact, and other specimens currently limits the application of experimental results. However, the available data suggest that the condition and representation of these items in the FLK 22 assemblage are also consistent with a carnivore to hominid to carnivore sequence of site formation. The variety of elements present, and their extensive

  12. Semiautomatic segmentation of liver metastases on volumetric CT images.

    Science.gov (United States)

    Yan, Jiayong; Schwartz, Lawrence H; Zhao, Binsheng

    2015-11-01

    Accurate segmentation and quantification of liver metastases on CT images are critical to surgery/radiation treatment planning and therapy response assessment. To date, there are no reliable methods to perform such segmentation automatically. In this work, the authors present a method for semiautomatic delineation of liver metastases on contrast-enhanced volumetric CT images. The first step is to manually place a seed region-of-interest (ROI) in the lesion on an image. This ROI will (1) serve as an internal marker and (2) assist in automatically identifying an external marker. With these two markers, lesion contour on the image can be accurately delineated using traditional watershed transformation. Density information will then be extracted from the segmented 2D lesion and help determine the 3D connected object that is a candidate of the lesion volume. The authors have developed a robust strategy to automatically determine internal and external markers for marker-controlled watershed segmentation. By manually placing a seed region-of-interest in the lesion to be delineated on a reference image, the method can automatically determine dual threshold values to approximately separate the lesion from its surrounding structures and refine the thresholds from the segmented lesion for the accurate segmentation of the lesion volume. This method was applied to 69 liver metastases (1.1-10.3 cm in diameter) from a total of 15 patients. An independent radiologist manually delineated all lesions and the resultant lesion volumes served as the "gold standard" for validation of the method's accuracy. The algorithm received a median overlap, overestimation ratio, and underestimation ratio of 82.3%, 6.0%, and 11.5%, respectively, and a median average boundary distance of 1.2 mm. Preliminary results have shown that volumes of liver metastases on contrast-enhanced CT images can be accurately estimated by a semiautomatic segmentation method.

  13. Semiautomatic segmentation of liver metastases on volumetric CT images

    International Nuclear Information System (INIS)

    Yan, Jiayong; Schwartz, Lawrence H.; Zhao, Binsheng

    2015-01-01

    Purpose: Accurate segmentation and quantification of liver metastases on CT images are critical to surgery/radiation treatment planning and therapy response assessment. To date, there are no reliable methods to perform such segmentation automatically. In this work, the authors present a method for semiautomatic delineation of liver metastases on contrast-enhanced volumetric CT images. Methods: The first step is to manually place a seed region-of-interest (ROI) in the lesion on an image. This ROI will (1) serve as an internal marker and (2) assist in automatically identifying an external marker. With these two markers, lesion contour on the image can be accurately delineated using traditional watershed transformation. Density information will then be extracted from the segmented 2D lesion and help determine the 3D connected object that is a candidate of the lesion volume. The authors have developed a robust strategy to automatically determine internal and external markers for marker-controlled watershed segmentation. By manually placing a seed region-of-interest in the lesion to be delineated on a reference image, the method can automatically determine dual threshold values to approximately separate the lesion from its surrounding structures and refine the thresholds from the segmented lesion for the accurate segmentation of the lesion volume. This method was applied to 69 liver metastases (1.1–10.3 cm in diameter) from a total of 15 patients. An independent radiologist manually delineated all lesions and the resultant lesion volumes served as the “gold standard” for validation of the method’s accuracy. Results: The algorithm received a median overlap, overestimation ratio, and underestimation ratio of 82.3%, 6.0%, and 11.5%, respectively, and a median average boundary distance of 1.2 mm. Conclusions: Preliminary results have shown that volumes of liver metastases on contrast-enhanced CT images can be accurately estimated by a semiautomatic segmentation

  14. Volumetric modulated arc radiotherapy for esophageal cancer

    International Nuclear Information System (INIS)

    Vivekanandan, Nagarajan; Sriram, Padmanaban; Syam Kumar, S.A.; Bhuvaneswari, Narayanan; Saranya, Kamalakannan

    2012-01-01

    A treatment planning study was performed to evaluate the performance of volumetric arc modulation with RapidArc (RA) against 3D conformal radiation therapy (3D-CRT) and conventional intensity-modulated radiation therapy (IMRT) techniques for esophageal cancer. Computed tomgraphy scans of 10 patients were included in the study. 3D-CRT, 4-field IMRT, and single-arc and double-arc RA plans were generated with the aim to spare organs at risk (OAR) and healthy tissue while enforcing highly conformal target coverage. The planning objective was to deliver 54 Gy to the planning target volume (PTV) in 30 fractions. Plans were evaluated based on target conformity and dose-volume histograms of organs at risk (lung, spinal cord, and heart). The monitor unit (MU) and treatment delivery time were also evaluated to measure the treatment efficiency. The IMRT plan improves target conformity and spares OAR when compared with 3D-CRT. Target conformity improved with RA plans compared with IMRT. The mean lung dose was similar in all techniques. However, RA plans showed a reduction in the volume of the lung irradiated at V 20Gy and V 30Gy dose levels (range, 4.62–17.98%) compared with IMRT plans. The mean dose and D 35% of heart for the RA plans were better than the IMRT by 0.5–5.8%. Mean V 10Gy and integral dose to healthy tissue were almost similar in all techniques. But RA plans resulted in a reduced low-level dose bath (15–20 Gy) in the range of 14–16% compared with IMRT plans. The average MU needed to deliver the prescribed dose by RA technique was reduced by 20–25% compared with IMRT technique. The preliminary study on RA for esophageal cancers showed improvements in sparing OAR and healthy tissue with reduced beam-on time, whereas only double-arc RA offered improved target coverage compared with IMRT and 3D-CRT plans.

  15. Coolability of volumetrically heated particle beds

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Muhammad

    2017-03-22

    In case of a severe nuclear reactor accident, with loss of coolant, a particle bed may be formed from the fragmentation of the molten core in the residual water at different stages of the accident. To avoid further propagation of the accident and maintain the integrity of the reactor pressure vessel, the decay heat of the particle bed must be removed. To better understand the various thermo-hydraulic processes within such heat-generating particle beds, the existing DEBRIS test facility at IKE has been modified to be able to perform novel boiling, dryout and quenching experiments. The essential experimental data includes the pressure gradients measured by 8 differential pressure transducers along the bed height as a function of liquid and vapour superficial velocities, the determination of local dryout heat fluxes for different system pressures as well as the local temperature distribution measured by a set of 51 thermocouples installed inside the particle bed. The experiments were carried out for two different particle beds: a polydispersed particle bed which consisted of stainless steel balls (2 mm, 3 mm and 6 mm diameters) and an irregular particle bed which consisted of a mixture of steel balls (3 mm and 6 mm) and irregularly shaped Al{sub 2}O{sub 3} particles. Additionally, all experiments were carried out for different flow conditions, such as the reference case of passive 1D top-flooding, 1D bottom flooding (driven by external pumps and different downcomer configurations) and 2D top-/bottom-/lateral flooding with a perforated downcomer. In this work, it has been observed that for both particle beds with downcomer configurations an open downcomer leads to the best coolability (dryout heat flux = 1560 kW/m{sup 2}, polydispersed particle bed, psys = 1 bar) of the particle bed, mainly due to bottom-flow with enhanced natural convection. It has also been shown that a potential lateral flow via a perforation of the downcomer does not bring any further improvements

  16. Volumetric Physics of Polypeptide Coil-Helix Transitions.

    Science.gov (United States)

    Krobath, Heinrich; Chen, Tao; Chan, Hue Sun

    2016-11-15

    Volumetric properties of proteins bear directly on their biological functions in hyperbaric environments and are useful in general as a biophysical probe. To gain insight into conformation-dependent protein volume, we developed an implicit-solvent atomic chain model that transparently embodies two physical origins of volume: (1) a fundamental geometric term capturing the van der Waals volume of the protein and the particulate, finite-size nature of the water molecules, modeled together by the volume encased by the protein's molecular surface, and (2) a physicochemical term for other solvation effects, accounted for by empirical proportionality relationships between experimental partial molar volumes and solvent-accessible surface areas of model compounds. We tested this construct by Langevin dynamics simulations of a 16-residue polyalanine. The simulated trajectories indicate an average volume decrease of 1.73 ± 0.1 Å 3 /residue for coil-helix transition, ∼80% of which is caused by a decrease in geometric void/cavity volume, and a robust positive activation volume for helical hydrogen bond formation originating from the transient void created by an approaching donor-acceptor pair and nearby atoms. These findings are consistent with prior experiments with alanine-rich peptides and offer an atomistic analysis of the observed overall volume changes. The results suggest, in general, that hydrostatic pressure likely stabilizes helical conformations of short peptides but slows the process of helix formation. In contrast, hydrostatic pressure is more likely to destabilize natural globular proteins because of the void volume entrapped in their folded structures. The conceptual framework of our model thus affords a coherent physical rationalization for experiments.

  17. Volumetric dimensional changes of dental light-cured dimethacrylate resins after sorption of water or ethanol.

    Science.gov (United States)

    Sideridou, Irini D; Karabela, Maria M; Vouvoudi, Evagelia Ch

    2008-08-01

    This study evaluated the influence of water and ethanol sorption on the volumetric dimensional changes of resins prepared by light curing of Bis-GMA, Bis-EMA, UDMA, TEGDMA or D(3)MA. The resin specimens (15mm diameterx1mm height) were immersed in water or ethanol 37+/-1 degrees C for 30 days. Volumetric changes of specimens were obtained via accurate mass measurements using Archimedes principle. The specimens were reconditioned by dry storage in an oven at 37+/-1 degrees C until constant mass was obtained and then immersed in water or ethanol for 30 days. The volumetric changes of specimens were determined and compared to those obtained from the first sorption. Resins showed similar volume increase during the first and second sorptions of water or ethanol. The volume increase due to water absorption is in the following order: poly-TEGDMA>poly-Bis-GMA>poly-UDMA>poly-Bis-EMA>poly-D(3)MA. On the contrary, the order in ethanol is poly-Bis-GMA>poly-UDMA>poly-TEGDMA>poly-Bis-EMA approximately poly-D(3)MA. The volume increase was found to depend linearly on the amount of water or ethanol absorbed. In the choice of monomers for preparation of composite resin matrix the volume increase in the resin after immersion in water or ethanol must be taken into account. Resins of Bis-EMA and D(3)MA showed the lowest values.

  18. Dental volumetric tomographical evaluation of location and prevalence of maxillary sinus septa

    Directory of Open Access Journals (Sweden)

    Ibrahim Damlar

    2013-06-01

    Full Text Available Purpose: The aim of this study was to determine the prevalence and location of maxillary sinus septa with the help of dental volumetric tomography. Methods: 760 patients’ 1520 maxillary sinus were evaluated by dental volumetric tomography for detecting maxillary sinus septa. Maxillary sinus was divided into 3 zones (anterior, middle and posterior zones while location of the maxillary sinus septa. Results: 47 of maxillary sinus septa existed in the anterior zone (24.7%, 35 of them in the middle zone (18.4% and 108 of them in the posterior region (56.8%. Conclusion: The formation of the maxillary sinus septa was affected by the existence or lack of the teeth. Correct detection of the presence of maxillary sinus septa was important prior to sinus lifting and dental implant surgery. Dental volumetric tomographical evaluation of maxillary sinus septa was more useful for a correct diagnosis and treatment planning. [Cukurova Med J 2013; 38(3.000: 467-474

  19. Extent of Endoscopic Resection for Anterior Skull Base Tumors: An MRI-Based Volumetric Analysis.

    Science.gov (United States)

    Koszewski, Ian J; Avey, Gregory; Ahmed, Azam; Leonhard, Lucas; Hoffman, Matthew R; McCulloch, Timothy M

    2017-06-01

    Objective  To determine the volume of ventral skull base tumor removed following endoscopic endonasal (EEA) resection using MRI-based volumetric analysis and to evaluate the inter-rater reliability of such analysis. Design  Retrospective case series. Setting  Academic tertiary care hospital. Participants  EEA patients November 2012 to August 2015. Main Outcome Measures  Volumetric analysis of pre- and immediately postoperative MR imaging was performed independently by two investigators. The percentage of total tumor resected was evaluated according to resection goal and tumor type. Results  A total of 39 patients underwent resection. Intraclass correlation coefficients between the raters were 0.9988 for preoperative and 0.9819 for postoperative images. Tumors (and average percentage removed) included 17 nonsecreting pituitary adenomas (95.3%), 8 secreting pituitary adenomas (86.2%), 4 meningiomas (81.6%), 3 olfactory neuroblastomas (100%), 2 craniopharyngiomas (100%), 1 large B-cell lymphoma (90.5%), 1 germ cell neoplasm (48.3), 1 benign fibrous connective tissue mass (93.4%), 1 epidermoid cyst (68.4%), and 1 chordoma (100%). For tumors treated with intent for gross total resection, 96.9 ± 4.8% was removed. Conclusion  EEAs achieved tumor resection rates of ∼97% when total resection was attempted. The radiographic finding of residual tumor is of uncertain clinical significance. The volumetric analysis employed in this study demonstrated high inter-rater reliability and could facilitate further study.

  20. Automatic left and right lung separation using free-formed surface fitting on volumetric CT.

    Science.gov (United States)

    Lee, Youn Joo; Lee, Minho; Kim, Namkug; Seo, Joon Beom; Park, Joo Young

    2014-08-01

    This study presents a completely automated method for separating the left and right lungs using free-formed surface fitting on volumetric computed tomography (CT). The left and right lungs are roughly divided using iterative 3-dimensional morphological operator and a Hessian matrix analysis. A point set traversing between the initial left and right lungs is then detected with a Euclidean distance transform to determine the optimal separating surface, which is then modeled from the point set using a free-formed surface-fitting algorithm. Subsequently, the left and right lung volumes are smoothly and directly separated using the separating surface. The performance of the proposed method was estimated by comparison with that of a human expert on 44 CT examinations. For all data sets, averages of the root mean square surface distance, maximum surface distance, and volumetric overlap error between the results of the automatic and the manual methods were 0.032 mm, 2.418 mm, and 0.017 %, respectively. Our study showed the feasibility of automatically separating the left and right lungs by identifying the 3D continuous separating surface on volumetric chest CT images.