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Sample records for dsc experimental method

  1. Reticulation of Aqueous Polyurethane Systems Controlled by DSC Method

    Directory of Open Access Journals (Sweden)

    Jakov Stamenkovic

    2006-06-01

    Full Text Available The DSC method has been employed to monitor the kinetics of reticulation ofaqueous polyurethane systems without catalysts, and with the commercial catalyst of zirconium(CAT®XC-6212 and the highly selective manganese catalyst, the complex Mn(III-diacetylacetonemaleinate (MAM. Among the polyol components, the acrylic emulsions wereused for reticulation in this research, and as suitable reticulation agents the water emulsiblealiphatic polyisocyanates based on hexamethylendoisocyanate with the different contents ofNCO-groups were employed. On the basis of DSC analysis, applying the methods of Kissinger,Freeman-Carroll and Crane-Ellerstein the pseudo kinetic parameters of the reticulation reactionof aqueous systems were determined. The temperature of the examination ranged from 50oC to450oC with the heat rate of 0.5oC/min. The reduction of the activation energy and the increaseof the standard deviation indicate the catalytic action of the selective catalysts of zirconium andmanganese. The impact of the catalysts on the reduction of the activation energy is thestrongest when using the catalysts of manganese and applying all the three afore-said methods.The least aberrations among the stated methods in defining the kinetic parameters wereobtained by using the manganese catalyst.

  2. Comparing Single-Point and Multi-point Calibration Methods in Modulated DSC

    Energy Technology Data Exchange (ETDEWEB)

    Van Buskirk, Caleb Griffith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-14

    Heat capacity measurements for High Density Polyethylene (HDPE) and Ultra-high Molecular Weight Polyethylene (UHMWPE) were performed using Modulated Differential Scanning Calorimetry (mDSC) over a wide temperature range, -70 to 115 °C, with a TA Instruments Q2000 mDSC. The default calibration method for this instrument involves measuring the heat capacity of a sapphire standard at a single temperature near the middle of the temperature range of interest. However, this method often fails for temperature ranges that exceed a 50 °C interval, likely because of drift or non-linearity in the instrument's heat capacity readings over time or over the temperature range. Therefore, in this study a method was developed to calibrate the instrument using multiple temperatures and the same sapphire standard.

  3. Improvement in Performance of ZnO based DSC Prepared by Spraying Method

    Directory of Open Access Journals (Sweden)

    Rangga Winantyo

    2013-09-01

    Full Text Available This paper reports the effect of TiCl4 on the performance of ZnO based DSC. ZnO was used due to its stability against photo-corrosion  and  photochemical  properties  similar  to  TiO2.  Thin  films  of  nanocrystalline  ZnO  were  deposited  on transparent conducting oxide glass using spray  method. The ZnO  films  were treated using TiCl4. The cell’s efficiency was found to be 2.5% with TiCl4 post-treatment and 1.9% without TiCl4 post-treatment.

  4. The Study of Phase Transformations of AlSi9Cu3 Alloy by DSC Method

    Directory of Open Access Journals (Sweden)

    Piątkowski J.

    2016-12-01

    Full Text Available With the use of differential scanning calorimetry (DSC, the characteristic temperatures and enthalpy of phase transformations were defined for commercial AlSi9Cu3 cast alloy (EN AC-46000 that is being used for example for pressurized castings for automotive industry. During the heating with the speed of 10°C·min−1 two endothermic effects has been observed. The first appears at the temperature between 495 °C and 534 °C, and the other between 555 °C and 631 °C. With these reactions the phase transformation enthalpy comes up as +6 J g−1 and +327 J g−1. During the cooling with the same speed, three endothermic reactions were observed at the temperatures between 584 °C and 471 °C. The total enthalpy of the transitions is – 348 J g−1.

  5. Influência de alguns parâmetros experimentais nos resultados de análises calorimétricas diferenciais - DSC Influence of some experimental parameters on the results of differential scanning calorimetry - DSC.

    OpenAIRE

    Cláudia Bernal; Andréa Boldarini Couto; Susete Trazzi Breviglieri; Éder Tadeu Gomes Cavalheiro

    2002-01-01

    A series of experiments were performed in order to demonstrate to undergraduate students or users of the differential scanning calorimetry (DSC), that several factors can influence the qualitative and quantitative aspects of DSC results. Saccharin, an artificial sweetner, was used as a probe and its thermal behavior is also discussed on the basis of thermogravimetric (TG) and DSC curves.

  6. Evaluation of the quasi-isothermal method of modulated DSC for heat capacity measurement

    International Nuclear Information System (INIS)

    Venkata Krishnan, R.; Nagarajan, K.

    2004-01-01

    Heat capacity measurements were carried out on ThO 2 by Modulated Differential Scanning Calorimetry (MDSC) using quasi-isothermal method in the temperature range 323-723 K. The highest accuracy of the heat capacity data obtained by this method was ± 2-3% which is much lower than that reported in the literature. (author)

  7. The Application of ATD and DSC Methods to Study of the EN AC-48000 Alloy Phase Transformations

    Directory of Open Access Journals (Sweden)

    Piątkowski J.

    2017-06-01

    Full Text Available Tests concerning EN AC 48000 (AlSi12CuNiMg alloy phase transition covered (ATD thermal analysis and (DSC differential scanning calorimetry specifying characteristic temperatures and enthalpy of transformations. ATD thermal analysis shows that during cooling there exist: pre-eutectic crystallization effect of Al9Fe2Si phase, double eutectic and crystallization α(Al+β(Si and multi-component eutectic crystallization. During heating, DSC curve showed endothermic effect connected with melting of the eutectic α(Al+β(Si and phases: Al2Cu, Al3Ni, Mg2Si and Al9Fe2Si being its components. The enthalpy of this transformation constitutes approx. +392 J g-1. During freezing of the alloy, DSC curve showed two exothermal reactions. One is most likely connected with crystallization of Al9Fe2Si phase and the second one comes from freezing of the eutectic α(Al+β(Si. The enthalpy of this transformation constitutes approx. -340 J g-1. Calorimetric test was accompanied by structural test (SEM conducted with the use of optical microscope Reichert and scanning microscope Hitachi S-4200. There occurred solution’s dendrites α(Al, eutectic silicon crystal (β and two types of eutectic solution: double eutectic α(Al+β(Si and multi-component eutectic α+AlSiCuNiMg+β.

  8. Effect of milling on DSC thermogram of excipient adipic acid.

    Science.gov (United States)

    Ng, Wai Kiong; Kwek, Jin Wang; Yuen, Aaron; Tan, Chin Lee; Tan, Reginald

    2010-03-01

    The purpose of this research was to investigate why and how mechanical milling results in an unexpected shift in differential scanning calorimetry (DSC) measured fusion enthalpy (Delta(fus)H) and melting point (T(m)) of adipic acid, a pharmaceutical excipient. Hyper differential scanning calorimetry (hyper-DSC) was used to characterize adipic acid before and after ball-milling. An experimental study was conducted to evaluate previous postulations such as electrostatic charging using the Faraday cage method, crystallinity loss using powder X-ray diffraction (PXRD), thermal annealing using DSC, impurities removal using thermal gravimetric analysis (TGA) and Karl Fischer titration. DSC thermograms showed that after milling, the values of Delta(fus)H and T(m) were increased by approximately 9% and 5 K, respectively. Previous suggestions of increased electrostatic attraction, change in particle size distribution, and thermal annealing during measurements did not explain the differences. Instead, theoretical analysis and experimental findings suggested that the residual solvent (water) plays a key role. Water entrapped as inclusions inside adipic acid during solution crystallization was partially evaporated by localized heating at the cleaved surfaces during milling. The correlation between the removal of water and melting properties measured was shown via drying and crystallization experiments. These findings show that milling can reduce residual solvent content and causes a shift in DSC results.

  9. Application of experimental design in examination of the dissolution rate of carbamazepine from formulations: Characterization of the optimal formulation by DSC, TGA, FT-IR and PXRD analysis

    Directory of Open Access Journals (Sweden)

    Krstić Marko

    2015-01-01

    Full Text Available Poor solubility is one of the key reasons for the poor bioavailability of these drugs. This paper displays a formulation of a solid surfactant system with carbamazepine, in order to increase its dissolution rate. Solid state surfactant systems are formed by application of fractal experimental design. Poloxamer 237 and Poloxamer 338 were used as surfactants and Brij® 35 was used as the co-surfactant. The ratios of the excipients and carbamazepine were varied and their effects on the dissolution rate of carbamazepine were examined. Moreover, the effects of the addition of natural (diatomite and a synthetic adsorbent carrier (Neusiline UFL2 on the dissolution rate of carbamazepine were also tested. The prepared surfactant systems were characterized and the influence of the excipients on possible changes of the polymorphous form of carbamazepine examined by application of analytical techniques (DSC, TGA, FT-IR, PXRD. It was determined that an appropriate selection of the excipient type and ratio could provide a significant increase in the carbamazepine dissolution rate. By application of analytical techniques, it was found that that the employed excipients induce a transition of carbamazepine into the amorphous form and that the selected sample was stable for three months, when kept under ambient conditions. [Projekat Ministarstva nauke Republike Srbije, br. TR34007

  10. Oil Analysis by Fast DSC

    NARCIS (Netherlands)

    Wetten, I.A.; Herwaarden, A.W.; Splinter, R.; Ruth, van S.M.

    2014-01-01

    Thermal analysis of Olive and Sunflower Oil is done by Fast DSC to evaluate its potential to replace DSC for adulteration detection. DSC measurements take hours, Fast DSC minutes. Peak temperatures of the crystallisation peak in cooling for different Olive and Sunflower Oils are both comparable to

  11. Experimental physics method

    International Nuclear Information System (INIS)

    Jeong, Yang Su; Oh, Byeong Seong

    2010-05-01

    This book introduces measurement and error, statistics of experimental data, population, sample variable, distribution function, propagation of error, mean and measurement of error, adjusting to rectilinear equation, common sense of error, experiment method, and record and statement. It also explains importance of error of estimation, systematic error, random error, treatment of single variable, significant figure, deviation, mean value, median, mode, sample mean, sample standard deviation, binomial distribution, gauss distribution, and method of least squares.

  12. Methods of experimental physics

    CERN Document Server

    Williams, Dudley

    1962-01-01

    Methods of Experimental Physics, Volume 3: Molecular Physics focuses on molecular theory, spectroscopy, resonance, molecular beams, and electric and thermodynamic properties. The manuscript first considers the origins of molecular theory, molecular physics, and molecular spectroscopy, as well as microwave spectroscopy, electronic spectra, and Raman effect. The text then ponders on diffraction methods of molecular structure determination and resonance studies. Topics include techniques of electron, neutron, and x-ray diffraction and nuclear magnetic, nuclear quadropole, and electron spin reson

  13. Comparative study of two methods of analysis crystallinity, x-ray and DSC, using a linear low density polyethylene (LLDPE) injected, irradiated by gamma radiation

    International Nuclear Information System (INIS)

    Oliveira, Ana C.F. de; Ferreto, Helio F.R.; Parra, Duclerc F.; Lugao, Ademar B.

    2015-01-01

    The linear low density polyethylene (LLDPE) is a linear polymer chain with short chain branching. In this work, the LLDPE was irradiated in "6"0Co gamma source with 2000 kCi of activity, in presence of air, with doses of 5, 10, 20, 50 or 100 kGy, at about 5 kGy.h-1 dose rate, at room temperature. After irradiation, the samples were heated for 60 min at 100 deg C to promote recombination and annihilation of residual radicals. LLDPE injected and irradiated samples were characterized to identity the effects of terminal degradation, scission and crosslinking occurred in each dose. In the radiation process has changes in the crystallization and thus it is possible to compare the methods to obtain the percentage of crystallization of PELDB by DSC and X-ray. (author)

  14. Differential scanning calorimetry (DSC) of semicrystalline polymers.

    Science.gov (United States)

    Schick, C

    2009-11-01

    Differential scanning calorimetry (DSC) is an effective analytical tool to characterize the physical properties of a polymer. DSC enables determination of melting, crystallization, and mesomorphic transition temperatures, and the corresponding enthalpy and entropy changes, and characterization of glass transition and other effects that show either changes in heat capacity or a latent heat. Calorimetry takes a special place among other methods. In addition to its simplicity and universality, the energy characteristics (heat capacity C(P) and its integral over temperature T--enthalpy H), measured via calorimetry, have a clear physical meaning even though sometimes interpretation may be difficult. With introduction of differential scanning calorimeters (DSC) in the early 1960s calorimetry became a standard tool in polymer science. The advantage of DSC compared with other calorimetric techniques lies in the broad dynamic range regarding heating and cooling rates, including isothermal and temperature-modulated operation. Today 12 orders of magnitude in scanning rate can be covered by combining different types of DSCs. Rates as low as 1 microK s(-1) are possible and at the other extreme heating and cooling at 1 MK s(-1) and higher is possible. The broad dynamic range is especially of interest for semicrystalline polymers because they are commonly far from equilibrium and phase transitions are strongly time (rate) dependent. Nevertheless, there are still several unsolved problems regarding calorimetry of polymers. I try to address a few of these, for example determination of baseline heat capacity, which is related to the problem of crystallinity determination by DSC, or the occurrence of multiple melting peaks. Possible solutions by using advanced calorimetric techniques, for example fast scanning and high frequency AC (temperature-modulated) calorimetry are discussed.

  15. Application of experimental design in examination of the dissolution rate of carbamazepine from formulations: Characterization of the optimal formulation by DSC, TGA, FT-IR and PXRD analysis

    OpenAIRE

    Krstić Marko; Ražić Slavica; Vasiljević Dragana; Spasojević Đurđija; Ibrić Svetlana

    2015-01-01

    Poor solubility is one of the key reasons for the poor bioavailability of these drugs. This paper displays a formulation of a solid surfactant system with carbamazepine, in order to increase its dissolution rate. Solid state surfactant systems are formed by application of fractal experimental design. Poloxamer 237 and Poloxamer 338 were used as surfactants and Brij® 35 was used as the co-surfactant. The ratios of the excipients and carbamazepine were varied...

  16. Experimental Methods in Media Research

    NARCIS (Netherlands)

    C.W. Handke (Christian); C. Herzog (Christian)

    2017-01-01

    textabstractCausal effects are a prime concern in media policy research, and experimental research designs are widely regarded as the most effective way to identify and gauge causality. Nevertheless, explicit applications of experimental methods are rare in media policy research. This chapter

  17. Experimental methods in behavioral teratology

    Energy Technology Data Exchange (ETDEWEB)

    Zbinden, G.

    1981-09-01

    Efforts are made to develop toxicological techniques with which new behavioral teratogens can be recognized. The review describes the most important experimental methods which are presently explored, and which are based on a rich body of knowledge accumulated by experimental psychologists. Most of the tests were developed with small animals, mostly with rats. They range from the rather straightforward determination of various reflexes to complex behavioral situations involving mechanical devices, operant conditioning techniques and procedures evaluating social behavior. In applying these methods in routine toxicology, it is important to remember, that many behavioral effects determined in newborn and adult animals are subtle. Moreover, they are influenced by a large variety of environmental factors affecting the health and the behavior of the mothers and of the offspring in the early and later phases of development. Therefore, the experiments must be conducted under highly standardized conditions and must be controlled rigorously. It is concluded that the best experimental strategy for the evaluation of potential behavioral teratogens is not yet established. Therefore, it would be premature to decide on a fixed protocol to be included in routine animal safety experiments for drugs and other chemical substances.

  18. In-situ study of the thermal properties of hydrate slurry by high pressure DSC

    Energy Technology Data Exchange (ETDEWEB)

    Sari, O.; Hu, J.; Brun, F.; Erbeau, N. [Institute of Thermal Engineering, University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Homsy, P. [Nestec, Vevey (Switzerland); Logel, J.-C. [Axima Refrigeration, Bischheim (France)

    2008-07-01

    Knowing the enthalpy of hydrate slurry is very essential for energy balance and industrial applications. No direct measurement processes had been developed in this field in the past time. A new experimental method with special device has been developed to carry out on-line measurement of the thermal properties for hydrate slurry under dynamic conditions. With this special device, it is possible to deliver the hydrate slurry to the high pressure DSC (Differential Scanning Calorimetry) directly from the production tank or pipes. Thermal data acquisition will be performed afterwards by DSC. The investigated conditions were at pressure of 30 bar and temperature of {approx}+7 {sup o}C. The dissociation enthalpy of CO{sub 2} hydrate slurry was about 54 kJ/kg, corresponding 10.8% of solid fraction. The on-line measurement results for CO{sub 2} hydrate slurry give a good tendency to apply this phase change slurry to the industrial refrigeration process. (author)

  19. Experimental methods in natural convection

    International Nuclear Information System (INIS)

    Koster, J.N.

    1982-11-01

    Some common experimental techniques to determine local velocities and to visualize temperature fields in natural convection research are discussed. First the physics and practice of anemometers are discussed with emphasis put on optical anemometers. In the second and third case the physics and practice of the most developed interferometers are discussed; namely differential interferometry for visualization of temperature gradient fields and holographic interferometry for visualization of temperature fields. At the Institut fuer Reaktorbauelemente these three measuring techniques are applied for convection and pipe flow studies. (orig.) [de

  20. Hydrogen concentration determination in pressure tube samples using differential scanning calorimetry (dsc)

    International Nuclear Information System (INIS)

    Marinescu, R.; Mincu, M.

    2015-01-01

    Zirconium alloys are widely used as a structural material in nuclear reactors. It is known that zirconium based cladding alloys absorb hydrogen as a result of service in a pressurized water reactor. Hydrogen absorbed (during operation of the reactor) in the zirconium alloy, out of which the pressure tube is made, is one of the major factors determining the life time of the pressure tube. For monitoring the hydrides, samples of the pressure tube are periodically taken and analyzed. At normal reactor operating temperature, hydrogen has limited solubility in the zirconium lattice and precipitates out of solid solution as zirconium hydride when the solid solubility is exceeded. As a consequences material characterization of Zr-2.5Nb CANDU pressure tubes is required after manufacturing but also during the operation to assess its structural integrity and to predict its behavior until the next in-service inspection. Hydrogen and deuterium concentration determination is one of the most important parameters to be evaluated during the experimental tests. Hydrogen present in zirconium alloys has a strong effect of weakening. Following the zirconium-hydrogen reaction, the resulting zirconium hydride precipitates in the mass of material. Weakening of the material, due to the presence of 10 ppm of precipitated hydrogen significantly affects some of its properties. The concentration of hydrogen in a sample can be determined by several methods, one of them being the differential scanning calorimetry (DSC). The principle of the method consists in measuring the difference between the amount of heat required to raise the temperature of a sample and a reference to a certain value. The experiments were made using a TA Instruments DSC Q2000 calorimeter. This paper contains experimental work for hydrogen concentration determination by Differential Scanning Calorimetry (DSC) method. Also, the reproducibility and accuracy of the method used at INR Pitesti are presented. (authors)

  1. Investigation on caloric requirement of biomass pyrolysis using TG-DSC analyzer

    Energy Technology Data Exchange (ETDEWEB)

    He Fang [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China)]. E-mail: hf@sdut.edu.cn; Yi Weiming [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China); Bai Xueyuan [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China)

    2006-09-15

    The caloric requirement of biomass pyrolysis has an important influence on the course of the thermal conversion. However, precise data are difficult to achieve by the current calculation method because of the complexity of the process. A new method for achieving the caloric requirement of the process by integrating the differential scanning calorimetry (DSC) curves was proposed after the simultaneous thermal analyzer (TG-DSC) and DSC curves were investigated. Experiments were conducted for wheat straw, cotton stalk, pine and peanut shell on a Netsch STA 449C analyzer. Powder samples were put into a platinum crucible with a lid on a high accuracy DSC-cp sample holder in the furnace and then heated from ambient temperature up to the maximum temperature of 973 K at the heating rate of 10 K/min in the analyzer. The product gases were swept away by 25 ml/min nitrogen. Mass changes (TG) and calorimetric effects (DSC) were recorded and analyzed. The process was investigated in detail through comparison of the DTG (differential thermogravimetric) and DSC curves of wheat straw. After the water influence in the DSC was eliminated, the relationship of the caloric requirement with the temperature of the aforementioned dry biomass was obtained by integrating the DSC curve. The results showed that 523 kJ, 459 kJ, 646 kJ and 385 kJ were required, respectively, to increase the temperature of 1 kg of dried wheat straw, cotton stalk, pine and peanut from 303 K to 673 K.

  2. Vapor pressure data for fatty acids obtained using an adaptation of the DSC technique

    Energy Technology Data Exchange (ETDEWEB)

    Matricarde Falleiro, Rafael M. [LPT, Departamento de Processos Quimicos (DPQ), Faculdade de Engenharia Quimica, Universidade de Campinas (UNICAMP), 13083-852 Campinas - SP (Brazil); Akisawa Silva, Luciana Y. [Departamento de Ciencias Exatas e da Terra, Universidade Federal de Sao Paulo (UNIFESP), 09972-270 Diadema - SP (Brazil); Meirelles, Antonio J.A. [EXTRAE, Departamento de Engenharia de Alimentos (DEA), Faculdade de Engenharia de Alimentos, Universidade de Campinas (UNICAMP), 13083-862 Campinas - SP (Brazil); Kraehenbuehl, Maria A., E-mail: mak@feq.unicamp.br [LPT, Departamento de Processos Quimicos (DPQ), Faculdade de Engenharia Quimica, Universidade de Campinas (UNICAMP), 13083-852 Campinas - SP (Brazil)

    2012-11-10

    Highlights: Black-Right-Pointing-Pointer Vapor pressure data of fatty acids were measured by Differential Scanning Calorimetry. Black-Right-Pointing-Pointer The DSC technique is especially advantageous for expensive chemicals. Black-Right-Pointing-Pointer High heating rate was used for measuring the vapor pressure data. Black-Right-Pointing-Pointer Antoine constants were obtained for the selected fatty acids. - Abstract: The vapor pressure data for lauric (C{sub 12:0}), myristic (C{sub 14:0}), palmitic (C{sub 16:0}), stearic (C{sub 18:0}) and oleic (C{sub 18:1}) acids were obtained using Differential Scanning Calorimetry (DSC). The adjustments made in the experimental procedure included the use of a small sphere (tungsten carbide) placed over the pinhole of the crucible (diameter of 0.8 mm), making it possible to use a faster heating rate than that of the standard method and reducing the experimental time. The measurements were made in the pressure range from 1333 to 9333 Pa, using small sample quantities of fatty acids (3-5 mg) at a heating rate of 25 K min{sup -1}. The results showed the effectiveness of the technique under study, as evidenced by the low temperature deviations in relation to the data reported in the literature. The Antoine constants were fitted to the experimental data whose values are shown in Table 5.

  3. Vapor pressure data for fatty acids obtained using an adaptation of the DSC technique

    International Nuclear Information System (INIS)

    Matricarde Falleiro, Rafael M.; Akisawa Silva, Luciana Y.; Meirelles, Antonio J.A.; Krähenbühl, Maria A.

    2012-01-01

    Highlights: ► Vapor pressure data of fatty acids were measured by Differential Scanning Calorimetry. ► The DSC technique is especially advantageous for expensive chemicals. ► High heating rate was used for measuring the vapor pressure data. ► Antoine constants were obtained for the selected fatty acids. - Abstract: The vapor pressure data for lauric (C 12:0 ), myristic (C 14:0 ), palmitic (C 16:0 ), stearic (C 18:0 ) and oleic (C 18:1 ) acids were obtained using Differential Scanning Calorimetry (DSC). The adjustments made in the experimental procedure included the use of a small sphere (tungsten carbide) placed over the pinhole of the crucible (diameter of 0.8 mm), making it possible to use a faster heating rate than that of the standard method and reducing the experimental time. The measurements were made in the pressure range from 1333 to 9333 Pa, using small sample quantities of fatty acids (3–5 mg) at a heating rate of 25 K min −1 . The results showed the effectiveness of the technique under study, as evidenced by the low temperature deviations in relation to the data reported in the literature. The Antoine constants were fitted to the experimental data whose values are shown in Table 5.

  4. Combined Teaching Method: An Experimental Study

    Science.gov (United States)

    Kolesnikova, Iryna V.

    2016-01-01

    The search for the best approach to business education has led educators and researchers to seek many different teaching strategies, ranging from the traditional teaching methods to various experimental approaches such as active learning techniques. The aim of this experimental study was to compare the effects of the traditional and combined…

  5. TOPEM DSC study of glass transition region of polyurethane cationomers

    International Nuclear Information System (INIS)

    Pielichowska, Kinga; Król, Piotr; Król, Bożena; Pagacz, Joanna

    2012-01-01

    Highlights: ► TOPEM DSC method was employed to investigate the glass transition (T g ) region of fluorinated polyurethane cationomers. ► Introduction of fluorine compounds significantly changes thermal behaviour of cationomers in the T g region of hard segments. ► Introduction of fluorine compound leads to changes of the slope in activation diagram of glass transition. - Abstract: In this paper TOPEM DSC method was employed to investigate the glass transition region of fluorinated polyurethane cationomers. Fluorinated polyurethane cationomers have been synthesised in the reaction of MDI with poly(ethylene glycol) (600) and butane1,4-diol or N-methyl- or N-butyldiethanolamine and 2,2,3,3-tetrafluoro-1,4-butanediol. Better rigidity was found for generally amorphous cationomer coats. It was found that introduction of fluorine compound changes thermal behaviour of polyurethane cationomers as well as leads to changes in the slope in activation diagram profiles of glass transition in comparison to polyuretahene cationomer without fluorine compound. Application of TOPEM DSC allows to obtain more information concerning frequency dependence of glass transition region and thermodynamical stability of polyurethane structures.

  6. RheoDSC: A hyphenated technique for the simultaneous measurement of calorimetric and rheological evolutions

    OpenAIRE

    Kiewiet, S; Janssens, V; Miltner, H. E; Van Assche, Gert; Van Puyvelde, Peter; Van Mele, B

    2008-01-01

    A newly developed hyphenated technique is presented combining an existing rheometer and differential scanning calorimeter into a single experimental setup. Through the development of a fixation accessory for differential scanning calorimeter (DSC) crucibles and a novel rotor, the simultaneous measurement is performed inside the well-controlled thermal environment of a Tzero (TM) DSC cell. Hence, the evolution of thermal and flow properties of a material can be simultaneously measured using st...

  7. IMPLICATIONS OF GLOBAL AND LOCAL MOBILITY IN AMORPHOUS EXCIPIENTS AS DETERMINED BY DSC AND TM DSC

    OpenAIRE

    Ion Dranca; Tudor Lupascu

    2009-01-01

    The paper explores the use of differential scanning calorimetry (DSC) and temperature modulated differential scanning calorimetry (TM DSC) to study α- and β- processes in amorphous sucrose and trehalose. The real part of the complex heat capacity is evaluated at the frequencies, f, from 5 to 20mHz. β-relaxations were studied by annealing glassy samples at different temperatures and subsequently heating at different rates in a differential scanning calorimeter.

  8. IMPLICATIONS OF GLOBAL AND LOCAL MOBILITY IN AMORPHOUS EXCIPIENTS AS DETERMINED BY DSC AND TM DSC

    Directory of Open Access Journals (Sweden)

    Ion Dranca

    2009-12-01

    Full Text Available The paper explores the use of differential scanning calorimetry (DSC and temperature modulated differential scanning calorimetry (TM DSC to study α- and β- processes in amorphous sucrose and trehalose. The real part of the complex heat capacity is evaluated at the frequencies, f, from 5 to 20mHz. β-relaxations were studied by annealing glassy samples at different temperatures and subsequently heating at different rates in a differential scanning calorimeter.

  9. Measurement for commercial exposives with SC-DSC test. Sangyoyo bakuhayaku no SC-DSC sokutei

    Energy Technology Data Exchange (ETDEWEB)

    Yabashi, H.; Wada, Y.; Hwang, D.; Akutsu, Y.; Tamura, M.; Yoshida, T. (The University of Tokyo, Tokyo (Japan). Faculty of Engineering); Matsuzawa, T. (Nippon Kayaku Co. Ltd., Tokyo (Japan))

    1991-08-30

    The sealed cell differential scanning calorimetry (SC-DSC) was sintroduced of commercial blasting explosives. As a series of testing the commercial blasting explosives in performance, an SC-DSC test was made to compare the critical detonability line with that resulting therefrom. From the result of SC-DSC measurement, the critical dilution rate was estimated of commercial blasting explosives to become without detonating propagation. As a result, all the explosives with exception of ANFO one were assumed to have a possibility of detonating propagation so that the ANFO explosive was known to be material, unable to exactly evaluate the detonability by the SC-DSC test. The explosion heat, then calculated by the REITP2 in order to assume how the reaction proceeded in the DSC cell, was compared with the reaction heat measured by the SC-DSC test. As a result, the calculated value was known to be almost equal to or slightly larger than the measured one. 15 refs., 4 figs., 2 tabs.

  10. Experimental study on rapid embankment construction methods

    International Nuclear Information System (INIS)

    Hirano, Hideaki; Egawa, Kikuji; Hyodo, Kazuya; Kannoto, Yasuo; Sekimoto, Tsuyoshi; Kobayashi, Kokichi.

    1982-01-01

    In the construction of a thermal or nuclear power plant in a coastal area, shorter embankment construction period has come to be called for recently. This tendency is remarkable where construction period is limited due to meteorological or sea conditions. To meet this requirement, the authors have been conducting basic experimental studies on two methods for the rapid execution of embankment construction, that is, Steel Plate Cellular Bulkhead Embedding Method and Ship Hull Caisson Method. This paper presents an outline of the results of the experimental study on these two methods. (author)

  11. An elegant access to formation and vaporization enthalpies of ionic liquids by indirect DSC experiment and "in silico" calculations.

    Science.gov (United States)

    Verevkin, Sergey P; Zaitsau, Dzmitry H; Emel'yanenko, Vladimir N; Schick, Christoph; Jayaraman, Saivenkataraman; Maginn, Edward J

    2012-07-14

    We used DSC for determination of the reaction enthalpy of the synthesis of the ionic liquid [C(4)mim][Cl]. A combination of DSC and quantum chemical calculations presents a new, indirect way to study thermodynamics of ionic liquids. The new procedure was validated with two direct experimental measurements and MD simulations.

  12. Forensic characterization of HDPE pipes by DSC.

    Science.gov (United States)

    Sajwan, Madhuri; Aggarwal, Saroj; Singh, R B

    2008-03-05

    The melting behavior of 28 high density polyethylene (HDPE) pipe samples manufactured and supplied by 13 different manufacturers in India was examined by 'differential scanning calorimetry (DSC)' to find out if this parameter could be used in differentiating between these HDPE pipe samples which are chemically the same and being manufactured by different manufacturer. The results indicate that the melting temperature may serve as the useful criteria for differentiating HDPE (i) pipe samples from different sources and (ii) samples of different diameter from the same source.

  13. A method for experimental modal separation

    Science.gov (United States)

    Hallauer, W. L., Jr.

    1977-01-01

    A method is described for the numerical simulation of multiple-shaker modal survey testing using simulated experimental data to optimize the shaker force-amplitude distribution for the purpose of isolating individual modes of vibration. Inertia, damping, stiffness, and model data are stored on magnetic disks, available by direct access to the interactive FORTRAN programs which perform all computations required by this relative force amplitude distribution method.

  14. TOPEM, a new temperature modulated DSC technique - Application to the glass transition of polymers

    OpenAIRE

    Fraga Rivas, Iria; Montserrat Ribas, Salvador; Hutchinson, John M.

    2007-01-01

    TOPEM is a new temperature modulated DSC technique, introduced by Mettler-Toledo in late 2005, in which stochastic temperature modulations are superimposed on the underlying rate of a conventional DSC scan. These modulations consist of temperature pulses, of fixed magnitude and alternating sign, with random durations within limits specified by the user. The resulting heat flow signal is analysed by a parameter estimation method which yields a so-called ‘quasi-static’ specific heat capac...

  15. The non-isothermal DSC kinetics of polyethylene tereftalate–epoxy compatible blends

    International Nuclear Information System (INIS)

    Zvetkov, V.L.; Djoumaliisky, S.; Simeonova-Ivanova, E.

    2013-01-01

    Highlights: ► The non-isothermal DSC kinetics of the reaction of DGEBA with DDS, in particular in the presence of phase separating PET, has been studied. ► The specific features in the kinetics of PET formulations in comparison to the pure system have been discussed. ► The fast pre-curing of the epoxy phase allows supposing sub-micro phase separation of PET and efficient toughening of the epoxy matrix. - Abstract: Polyethylene tereftalate has been dissolved in an epoxy resin based on diglycidyl ether of bisphenol-A, DGEBA, and the epoxy component has been cross-linked with the aid of two diamine hardeners. Two series of samples have been tested at the epoxy-amine stoichiometry applying the differential scanning calorimetry, DSC, in scanning mode. One of the series of samples was pre-cured at low temperatures with the aid of an aliphatic diamine hardener near the gel point and post-cured with diaminodiphenyl sulfone, DDS. The other series of samples contained the higher temperature hardener only. Consequently, the experimental data obtained in this study on both systems relate to the non-isothermal curing of DGEBA with DDS. The kinetics has been estimated applying preferably isoconversional (model free) methods. It has been established that the fast pre-curing allows performing a sub-micro phase separation and efficient toughening of the epoxy matrix

  16. The non-isothermal DSC kinetics of polyethylene tereftalate–epoxy compatible blends

    Energy Technology Data Exchange (ETDEWEB)

    Zvetkov, V.L., E-mail: zvetval@yahoo.com [Institute of Mechanics, Bulgarian Academy of Sciences, bl. I, Sofia 1113 (Bulgaria); Djoumaliisky, S.; Simeonova-Ivanova, E. [Institute of Mechanics, Bulgarian Academy of Sciences, bl. I, Sofia 1113 (Bulgaria)

    2013-02-10

    Highlights: ► The non-isothermal DSC kinetics of the reaction of DGEBA with DDS, in particular in the presence of phase separating PET, has been studied. ► The specific features in the kinetics of PET formulations in comparison to the pure system have been discussed. ► The fast pre-curing of the epoxy phase allows supposing sub-micro phase separation of PET and efficient toughening of the epoxy matrix. - Abstract: Polyethylene tereftalate has been dissolved in an epoxy resin based on diglycidyl ether of bisphenol-A, DGEBA, and the epoxy component has been cross-linked with the aid of two diamine hardeners. Two series of samples have been tested at the epoxy-amine stoichiometry applying the differential scanning calorimetry, DSC, in scanning mode. One of the series of samples was pre-cured at low temperatures with the aid of an aliphatic diamine hardener near the gel point and post-cured with diaminodiphenyl sulfone, DDS. The other series of samples contained the higher temperature hardener only. Consequently, the experimental data obtained in this study on both systems relate to the non-isothermal curing of DGEBA with DDS. The kinetics has been estimated applying preferably isoconversional (model free) methods. It has been established that the fast pre-curing allows performing a sub-micro phase separation and efficient toughening of the epoxy matrix.

  17. Experimental methods of shock wave research

    CERN Document Server

    Seiler, Friedrich

    2016-01-01

    This comprehensive and carefully edited volume presents a variety of experimental methods used in Shock Waves research. In 14 self contained chapters this 9th volume of the “Shock Wave Science and Technology Reference Library” presents the experimental methods used in Shock Tubes, Shock Tunnels and Expansion Tubes facilities. Also described is their set-up and operation. The uses of an arc heated wind tunnel and a gun tunnel are also contained in this volume. Whenever possible, in addition to the technical description some typical scientific results obtained using such facilities are described. Additionally, this authoritative book includes techniques for measuring physical properties of blast waves and laser generated shock waves. Information about active shock wave laboratories at different locations around the world that are not described in the chapters herein is given in the Appendix, making this book useful for every researcher involved in shock/blast wave phenomena.

  18. Surface physics theoretical models and experimental methods

    CERN Document Server

    Mamonova, Marina V; Prudnikova, I A

    2016-01-01

    The demands of production, such as thin films in microelectronics, rely on consideration of factors influencing the interaction of dissimilar materials that make contact with their surfaces. Bond formation between surface layers of dissimilar condensed solids-termed adhesion-depends on the nature of the contacting bodies. Thus, it is necessary to determine the characteristics of adhesion interaction of different materials from both applied and fundamental perspectives of surface phenomena. Given the difficulty in obtaining reliable experimental values of the adhesion strength of coatings, the theoretical approach to determining adhesion characteristics becomes more important. Surface Physics: Theoretical Models and Experimental Methods presents straightforward and efficient approaches and methods developed by the authors that enable the calculation of surface and adhesion characteristics for a wide range of materials: metals, alloys, semiconductors, and complex compounds. The authors compare results from the ...

  19. Determination of melting point of vegetable oils and fats by differential scanning calorimetry (DSC technique.

    Directory of Open Access Journals (Sweden)

    Nassu, Renata Tieko

    1999-02-01

    Full Text Available Melting point of fats is used to characterize oils and fats and is related to their physical properties, such as hardness and thermal behaviour. The present work shows the utilization of DSC technique on the determination of melting point of fats. In a comparison with softening point (AOCS method Cc 3-25, DSC values were higher than those obtained by AOCS method. It has occurred due to the fact that values obtained by DSC technique were taken when the fat had melted completely. DSC was also useful for determining melting point of liquid oils, such as soybean and cottonseed ones.

    El punto de fusión de grasas es usado para caracterizar aceites y grasas, y está relacionado con sus propiedades físicas, tales como dureza y comportamiento térmico. El presente trabajo muestra la utilización de la técnica de Calorimetría Diferencial de Barrido (DSC en la determinación del punto de fusión de grasas. En comparación con el punto de ablandamiento (AOCS método Cc 3-25, los valores de DSC fueron más altos que los obtenidos por los métodos de AOCS. Esto ha ocurrido debido al hecho que los valores obtenidos por la técnica de DSC fueron tomados cuando la grasa había fundido completamente. DSC fue también útil para determinar puntos de fusión de aceites líquidos, tales como los de soya y algodón.

  20. Differential scanning calorimetry (DSC) and temperature-modulated DSC study of three mouthguard materials.

    Science.gov (United States)

    Meng, Frank H; Schricker, Scott R; Brantley, William A; Mendel, Deborah A; Rashid, Robert G; Fields, Henry W; Vig, Katherine W L; Alapati, Satish B

    2007-12-01

    Employ differential scanning calorimetry (DSC) and temperature-modulated DSC (TMDSC) to investigate thermal transformations in three mouthguard materials and provide insight into their previously investigated energy absorption. Samples (13-21mg) were obtained from (a) conventional ethylene vinyl acetate (EVA), (b) Pro-form, another EVA polymer, and (c) PolyShok, an EVA polymer containing polyurethane. Conventional DSC (n=5) was first performed from -80 to 150 degrees C at a heating rate of 10 degrees C/min to determine the temperature range for structural transformations. Subsequently, TMDSC (n=5) was performed from -20 to 150 degrees C at a heating rate of 1 degrees C/min. Onset and peak temperatures were compared using ANOVA and the Tukey-Kramer HSD test. Other samples were coated with a gold-palladium film and examined with an SEM. DSC and TMDSC curves were similar for both conventional EVA and Pro-form, showing two endothermic peaks suggestive of melting processes, with crystallization after the higher-temperature peak. Evidence for crystallization and the second endothermic peak were much less prominent for PolyShok, which had no peaks associated with the polyurethane constituent. The onset of the lower-temperature endothermic transformation is near body temperature. No glass transitions were observed in the materials. SEM examination revealed different surface morphology and possible cushioning effect for PolyShok, compared to Pro-form and EVA. The difference in thermal behavior for PolyShok is tentatively attributed to disruption of EVA crystal formation, which may contribute to its superior impact resistance. The lower-temperature endothermic peak suggests that impact testing of these materials should be performed at 37 degrees C.

  1. TG-FTIR, DSC and quantum chemical studies of the thermal decomposition of quaternary methylammonium halides

    International Nuclear Information System (INIS)

    Sawicka, Marlena; Storoniak, Piotr; Skurski, Piotr; Blazejowski, Jerzy; Rak, Janusz

    2006-01-01

    The thermal decomposition of quaternary methylammonium halides was studied using thermogravimetry coupled to FTIR (TG-FTIR) and differential scanning calorimetry (DSC) as well as the DFT, MP2 and G2 quantum chemical methods. There is almost perfect agreement between the experimental IR spectra and those predicted at the B3LYP/6-311G(d,p) level: this has demonstrated for the first time that an equimolar mixture of trimethylamine and a methyl halide is produced as a result of decomposition. The experimental enthalpies of dissociation are 153.4, 171.2, and 186.7 kJ/mol for chloride, bromide and iodide, respectively, values that correlate well with the calculated enthalpies of dissociation based on crystal lattice energies and quantum chemical thermodynamic barriers. The experimental activation barriers estimated from the least-squares fit of the F1 kinetic model (first-order process) to thermogravimetric traces - 283, 244 and 204 kJ/mol for chloride, bromide and iodide, respectively - agree very well with theoretically calculated values. The theoretical approach assumed in this work has been shown capable of predicting the relevant characteristics of the thermal decomposition of solids with experimental accuracy

  2. Methods and experimental techniques in computer engineering

    CERN Document Server

    Schiaffonati, Viola

    2014-01-01

    Computing and science reveal a synergic relationship. On the one hand, it is widely evident that computing plays an important role in the scientific endeavor. On the other hand, the role of scientific method in computing is getting increasingly important, especially in providing ways to experimentally evaluate the properties of complex computing systems. This book critically presents these issues from a unitary conceptual and methodological perspective by addressing specific case studies at the intersection between computing and science. The book originates from, and collects the experience of, a course for PhD students in Information Engineering held at the Politecnico di Milano. Following the structure of the course, the book features contributions from some researchers who are working at the intersection between computing and science.

  3. Multiple-specimen absolute paleointensity determination with the MSP-DSC protocol: Advantages and drawbacks.

    Science.gov (United States)

    Camps, P.; Fanjat, G.; Poidras, T.; Carvallo, C.; Nicol, P.

    2012-04-01

    The MSP-DSC protocol (Dekkers & Bohnel, 2006, EPSL; Fabian & Leonhardt, 2010, EPSL) is a recent development in the methodology for documenting the intensity of the ancient Earth magnetic field. Applicable both on rocks or archaeological artifacts it allows us to use samples that until now were not measured because their magnetic properties do not meet selection criteria required by conventional methods. However, this new experimental protocol requires that samples be heated and cooled under a field parallel to its natural remanent magnetization (NRM). Currently, standard paleointensity furnaces do not match precisely this constraint. Yet, such new measurement protocol seems very promising since it would possibly double the number of available data. We are developing in Montpellier (France), a very fast-heating oven with infrared dedicated to this protocol. Two key points determine its characteristics. The first is to heat uniformly a rock sample of a 10-cc-standard volume as fast as possible. The second is to apply to the sample during the heating (and the cooling) a precise magnetic induction field, perfectly controlled in 3D. We tested and calibrated a preliminary version of this oven along with the MSP-DSC protocol with 3 historical lava flows, 2 from Reunion Island (erupted in 2002 and 2007) and one from Etna (erupted in 1983). These lava flows were selected because they have different magnetic behaviors. Reunion 2002 is rather SD-PSD-like, while Reunion 2007 is PSD-MD-like, and Etna 1983 is MD-like. The paleointensity determinations obtained with the original protocol of Dekkers and Bohnel (2006, EPSL) are within +- 1 μT of the known field for the three lava flows. The same precision is obtained when we applied the fraction correction (MSP-FC protocol). However, we systematically observed a loss in the linearity of the MSP-FC plots. In addition, like Muxworthy and Taylor (2011, GJI), we found that the Domain State Correction is difficult to apply since alpha

  4. Non-isothermal dehydration kinetic study of aspartame hemihydrate using DSC, TGA and DSC-FTIR microspectroscopy

    Directory of Open Access Journals (Sweden)

    Wei-hsien Hsieh

    2018-05-01

    Full Text Available Three thermal analytical techniques such as differential scanning calorimetry (DSC, thermal gravimetric analysis (TGA using five heating rates, and DSC-Fourier Transform Infrared (DSC-FTIR microspectroscopy using one heating rate, were used to determine the thermal characteristics and the dehydration process of aspartame (APM hemihydrate in the solid state. The intramolecular cyclization process of APM anhydrate was also examined. One exothermic and four endothermic peaks were observed in the DSC thermogram of APM hemihydrate, in which the exothermic peak was due to the crystallization of some amorphous APM caused by dehydration process from hemihydrate to anhydride. While four endothermic peaks were corresponded to the evaporation of absorbed water, the dehydration of hemihydrate, the diketopiperazines (DKP formation via intramolecular cyclization, and the melting of DKP, respectively. The weight loss measured in TGA curve of APM hemihydrate was associated with these endothermic peaks in the DSC thermogram. According to the Flynn–Wall–Ozawa (FWO model, the activation energy of dehydration process within 100–150 °C was about 218 ± 11 kJ/mol determined by TGA technique. Both the dehydration and DKP formation processes for solid-state APM hemihydrate were markedly evidenced from the thermal-responsive changes in several specific FTIR bands by a single-step DSC-FTIR microspectroscopy. Keywords: Aspartame (APM hemihydrate, DSC/TGA, DSC-FTIR, Dehydration, Activation energy, DKP formation

  5. Thermal analysis and safety information for metal nanopowders by DSC

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, J.M.; Huang, S.T. [Institute of Safety and Disaster Prevention Technology, Central Taiwan University of Science and Technology, 666, Buzih Road, Beitun District, Taichung 40601, Taiwan, ROC (China); Duh, Y.S.; Hsieh, T.Y.; Sun, Y.Y. [Department of Safety Health and Environmental Engineering, National United University, Miaoli, Taiwan, ROC (China); Lin, J.Z. [Institute of Safety and Disaster Prevention Technology, Central Taiwan University of Science and Technology, 666, Buzih Road, Beitun District, Taichung 40601, Taiwan, ROC (China); Wu, H.C. [Institute of Occupational Safety and Health, Council of Labor Affairs, Taipei, Taiwan, ROC (China); Kao, C.S., E-mail: jcsk@nuu.edu.tw [Department of Safety Health and Environmental Engineering, National United University, Miaoli, Taiwan, ROC (China)

    2013-08-20

    Highlights: • Metal nanopowders are common and frequently employed in industry. • Nano iron powder experimental results of T{sub o} were 140–150 °C. • Safety information can benefit relevant metal powders industries. - Abstract: Metal nanopowders are common and frequently employed in industry. Iron is mostly applied in high-performance magnetic materials and pollutants treatment for groundwater. Zinc is widely used in brass, bronze, die casting metal, alloys, rubber, and paints, etc. Nonetheless, some disasters induced by metal powders are due to the lack of related safety information. In this study, we applied differential scanning calorimetry (DSC) and used thermal analysis software to evaluate the related thermal safety information, such as exothermic onset temperature (T{sub o}), peak of temperature (T{sub p}), and heat of reaction (ΔH). The nano iron powder experimental results of T{sub o} were 140–150 °C, 148–158 °C, and 141–149 °C for 15 nm, 35 nm, and 65 nm, respectively. The ΔH was larger than 3900 J/g, 5000 J/g, and 3900 J/g for 15 nm, 35 nm, and 65 nm, respectively. Safety information can benefit the relevant metal powders industries for preventing accidents from occurring.

  6. Multispectral Image Compression Based on DSC Combined with CCSDS-IDC

    Directory of Open Access Journals (Sweden)

    Jin Li

    2014-01-01

    Full Text Available Remote sensing multispectral image compression encoder requires low complexity, high robust, and high performance because it usually works on the satellite where the resources, such as power, memory, and processing capacity, are limited. For multispectral images, the compression algorithms based on 3D transform (like 3D DWT, 3D DCT are too complex to be implemented in space mission. In this paper, we proposed a compression algorithm based on distributed source coding (DSC combined with image data compression (IDC approach recommended by CCSDS for multispectral images, which has low complexity, high robust, and high performance. First, each band is sparsely represented by DWT to obtain wavelet coefficients. Then, the wavelet coefficients are encoded by bit plane encoder (BPE. Finally, the BPE is merged to the DSC strategy of Slepian-Wolf (SW based on QC-LDPC by deep coupling way to remove the residual redundancy between the adjacent bands. A series of multispectral images is used to test our algorithm. Experimental results show that the proposed DSC combined with the CCSDS-IDC (DSC-CCSDS-based algorithm has better compression performance than the traditional compression approaches.

  7. Multispectral image compression based on DSC combined with CCSDS-IDC.

    Science.gov (United States)

    Li, Jin; Xing, Fei; Sun, Ting; You, Zheng

    2014-01-01

    Remote sensing multispectral image compression encoder requires low complexity, high robust, and high performance because it usually works on the satellite where the resources, such as power, memory, and processing capacity, are limited. For multispectral images, the compression algorithms based on 3D transform (like 3D DWT, 3D DCT) are too complex to be implemented in space mission. In this paper, we proposed a compression algorithm based on distributed source coding (DSC) combined with image data compression (IDC) approach recommended by CCSDS for multispectral images, which has low complexity, high robust, and high performance. First, each band is sparsely represented by DWT to obtain wavelet coefficients. Then, the wavelet coefficients are encoded by bit plane encoder (BPE). Finally, the BPE is merged to the DSC strategy of Slepian-Wolf (SW) based on QC-LDPC by deep coupling way to remove the residual redundancy between the adjacent bands. A series of multispectral images is used to test our algorithm. Experimental results show that the proposed DSC combined with the CCSDS-IDC (DSC-CCSDS)-based algorithm has better compression performance than the traditional compression approaches.

  8. A Research Agenda on Data Supply Chains (DSC)

    OpenAIRE

    Spanaki, K; Adams, R; Mulligan, C; Lupu, E

    2016-01-01

    Competition among organizations supports initiatives and collaborative use of data while creating value based on the strategy and best performance of each data supply chain. Supporting this direction, and building on the theoretical background of the supply chain, we propose the Data Supply Chain (DSC) as a novel concept to aid investigations for data-driven collaboration impacting organizational performance. In this study we initially propose a definition for the DSC paying particular attent...

  9. Experimental methods to study tokamak plasma stability

    International Nuclear Information System (INIS)

    Perez-Navarro, A.

    1978-01-01

    Experimental devices to measure external instability modes with small pick-up coils to detect poloidal magnetic field fluctuations, and internal modes with soft-X-ray detectors are discussed. The characteristics of these devices are calculated for a small tokamak (R 0 = 30 cm, a = 10 cm, I 0 50 KA). (author)

  10. Experimental methods of effective delayed neutron fraction

    International Nuclear Information System (INIS)

    Yamaye, Yoshihiro

    1995-01-01

    The defining principle and examples of β eff measurement method: the substitutional method, Cf neutron source method, Bennett method, the coupling coefficient method and Nelson method were introduced and surveyed. Measurement errors and C/E value of the substitutional, Cf ray source and Bennett method were of the order of 3%, 5% and 3 - 6% and 0.903 - 0.965, 1.85 and 1.019 - 1.165, respectably. Evaluation of the absolute value is so hard that β eff measurement belongs to the difficult experiment. The dependence on nuclear calculation in decreasing order is the substitutional, Cf ray source, Bennett, the coupling coefficient and Nelson number method. If good substitute materials were selected, the substitutional method has possibility to determine β eff by small correction value or independent on calculation. (S.Y.)

  11. Molecular physics. Theoretical principles and experimental methods

    International Nuclear Information System (INIS)

    Demtroeder, W.

    2005-01-01

    This advanced textbook comprehensively explains important principles of diatomic and polyatomic molecules and their spectra in two separate, distinct parts. The first part concentrates on the theoretical aspects of molecular physics, whereas the second part of the book covers experimental techniques, i.e. laser, Fourier, NMR, and ESR spectroscopies, used in the fields of physics, chemistry, biolog, and material science. Appropriate for undergraduate and graduate students in physics and chemistry with a knowledge of atomic physics and familiar with the basics of quantum mechanics. From the contents: - Electronic States of Molecules, - Rotation, Oscillation and Potential Curves of Diatomic Molecules, - The Spectra of Diatomic Molecules, - Molecule Symmetries and Group Theory, - Rotation and Oscillations of Polyatomic Molecules, - Electronic States of Polyatomic Molecules, - The Spectra of Polyatomic Molecules, - Collapse of the Born-Oppenheimer-Approximation, Disturbances in Molecular Spectra, - Molecules in Disturbing Fields, - Van-der-Waals-Molecules and Cluster, - Experimental Techniques in Molecular Physics. (orig.)

  12. Method to deterministically study photonic nanostructures in different experimental instruments

    NARCIS (Netherlands)

    Husken, B.H.; Woldering, L.A.; Blum, Christian; Tjerkstra, R.W.; Vos, Willem L.

    2009-01-01

    We describe an experimental method to recover a single, deterministically fabricated nanostructure in various experimental instruments without the use of artificially fabricated markers, with the aim to study photonic structures. Therefore, a detailed map of the spatial surroundings of the

  13. Application of the photoelastic experimental hybrid method with new numerical method to the high stress distribution

    International Nuclear Information System (INIS)

    Hawong, Jai Sug; Lee, Dong Hun; Lee, Dong Ha; Tche, Konstantin

    2004-01-01

    In this research, the photoelastic experimental hybrid method with Hook-Jeeves numerical method has been developed: This method is more precise and stable than the photoelastic experimental hybrid method with Newton-Rapson numerical method with Gaussian elimination method. Using the photoelastic experimental hybrid method with Hook-Jeeves numerical method, we can separate stress components from isochromatics only and stress intensity factors and stress concentration factors can be determined. The photoelastic experimental hybrid method with Hook-Jeeves had better be used in the full field experiment than the photoelastic experimental hybrid method with Newton-Rapson with Gaussian elimination method

  14. Clinical experimental stress studies: methods and assessment.

    Science.gov (United States)

    Bali, Anjana; Jaggi, Amteshwar Singh

    2015-01-01

    Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Stress induction methods are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these methods are also important for the development of novel pharmacological agents for stress management. The well-described methods to induce stress in humans include the cold pressor test, Trier Social Stress Test, Montreal Imaging Stress Task, Maastricht Acute Stress Test, CO2 challenge test, Stroop test, Paced Auditory Serial Addition Task, noise stress, and Mannheim Multicomponent Stress Test. Stress assessment in humans is done by measuring biochemical markers such as cortisol, cortisol awakening response, dexamethasone suppression test, salivary α-amylase, plasma/urinary norepinephrine, norepinephrine spillover rate, and interleukins. Physiological and behavioral changes such as galvanic skin response, heart rate variability, pupil size, and muscle and/or skin sympathetic nerve activity (microneurography) and cardiovascular parameters such as heart rate, blood pressure, and self-reported anxiety are also monitored to assess stress response. This present review describes these commonly employed methods to induce stress in humans along with stress assessment methods.

  15. Estimation of hydrogen bondings in coal utilizing FTir and differential scanning calorimetry (DSC); FTir to DSC wo mochiita sekitannai suiso ketsugo no teiryoteki hyoka no kokoromi

    Energy Technology Data Exchange (ETDEWEB)

    Mae, K.; Miura, K. [Kyoto University, Kyoto (Japan). Faculty of Engineering

    1996-10-28

    With an objective to know coal condensation structure which has influence on coal conversion reaction, an attempt was made on quantitative evaluation of hydrogen bonding in coal. Using as test samples the VDC made from Taiheiyo coal swollen by tetralin and vacuum-dried, and its pyrolyzed char, DSC measurement and Fourier transform infrared spectroscopy (FT) were performed. An FT spectrum comparison revealed that the VDC swollen at 220{degree}C has the hydrogen bonding relaxed partly from the original coal. However, since the change is in a huge coal molecular structure restraining space, it has stopped at relaxation of the bonding energy without causing separation as far as free radicals. On the other hand, the DSC curve shows that the VDC has slower endothermic velocity than the original coal. In other words, the difference in heat absorption amounts in both materials is equivalent to the difference of enthalpy ({Delta} H) of both materials, which corresponds to the relaxation of the hydrogen bonding. Therefore, the {Delta} H was related to wavenumber shift of the FT spectra (which corresponds to change in the hydrogen bonding condition). By using this relationship, a method for evaluating hydrogen bonding distribution was proposed from an O-H contracting vibration change that can be measured by using the FT spectra and a thermal change that can be measured by using the DSC. 3 refs., 7 figs.

  16. Thermal degradation of ligno-cellulosic fuels. DSC and TGA studies

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, V.; Cancellieri, D.; Leoni, E. [SPE-CNRS UMR 6134, University of Corsica, Campus Grossetti, BP 52, 20250 Corti (France)

    2006-12-01

    The scope of this work was to show the utility of thermal analysis and calorimetric experiments to study the thermal oxidative degradation of Mediterranean scrubs. We investigated the thermal degradation of four species; DSC and TGA were used under air sweeping to record oxidative reactions in dynamic conditions. Heat released and mass loss are important data to be measured for wildland fires modelling purpose and fire hazard studies on ligno-cellulosic fuels. Around 638 and 778K, two dominating and overlapped exothermic peaks were recorded in DSC and individualized using a experimental and numerical separation. This stage allowed obtaining the enthalpy variation of each exothermic phenomenon. As an application, we propose to classify the fuels according to the heat released and the rate constant of each reaction. TGA experiments showed under air two successive mass loss around 638 and 778K. Both techniques are useful in order to measure ignitability, combustibility and sustainability of forest fuels. (author)

  17. Experimental modeling methods in Industrial Engineering

    Directory of Open Access Journals (Sweden)

    Peter Trebuňa

    2009-03-01

    Full Text Available Dynamic approaches to a management system of the present industrial practice, forcing businesses to address management issues in-house continuous improvement of production and non-production processes. Experience has repeatedly demonstrated the need for a system approach not only in analysis but also in the planning and actual implementation of these processes. Therefore, the contribution is focused on the description of the modeling in industrial practice by a system approach, in order to avoid erroneous application of the decision to the implementation phase, and thus prevent any longer applying methods "attempt - fallacy".

  18. Acquisition of Psychomotor Skills in Dentistry: An Experimental Teaching Method.

    Science.gov (United States)

    Vann, William F., Jr.; And Others

    1981-01-01

    A traditional method of teaching psychomotor skills in a preclinical restorative dentistry laboratory course was compared with an experimental method. The experimental group was taught using a guided systematic approach that relied on detailed checklists and exhaustive faculty feedback. (Author/MLW)

  19. Review of experimental methods for evaluating effective delayed neutron fraction

    Energy Technology Data Exchange (ETDEWEB)

    Yamane, Yoshihiro [Nagoya Univ. (Japan). School of Engineering

    1997-03-01

    The International Effective Delayed Neutron Fraction ({beta}{sub eff}) Benchmark Experiments have been carried out at the Fast Critical Assembly of Japan Atomic Energy Research Institute since 1995. Researchers from six countries, namely France, Italy, Russia, U.S.A., Korea, and Japan, participate in this FCA project. Each team makes use of each experimental method, such as Frequency Method, Rossi-{alpha} Method, Nelson Number Method, Cf Neutron Source Method, and Covariance Method. In this report these experimental methods are reviewed. (author)

  20. Experimental Methods in Psychology and Cognitive and Affective Neuroscience

    DEFF Research Database (Denmark)

    Habekost, Thomas; Nielsen, Julie Hassing

    2014-01-01

    studies are central. Recently, experimental studies within the field of affective neuroscience have also received attention. Notwithstanding, experimental methods remain controversial also in psychology, and one should carefully weigh their advantages against their drawbacks.......Laboratory experiments have always been important in psychology and are as commonly used today as ever due to the dominating position of cognitive research in international psychology. This trend has been further strengthened by recent developments in cognitive neuroscience, where experimental...

  1. Experimental Methods in Psychology and Cognitive and Affective Neuroscience

    OpenAIRE

    Habekost, Thomas; Nielsen, Julie Hassing

    2014-01-01

    Laboratory experiments have always been important in psychology and are as commonly used today as ever due to the dominating position of cognitive research in international psychology. This trend has been further strengthened by recent developments in cognitive neuroscience, where experimental studies are central. Recently, experimental studies within the fi eld of affective neuroscience have also received attention. Notwithstanding, experimental methods remain controversial also in psychology...

  2. Methods for the neutronic design of a Supersara experimental loop

    International Nuclear Information System (INIS)

    Casali, F.; Cepraga, D.

    1982-01-01

    This paper describes a method for the neutronic design of experimental loops irradiated in D 2 O experimental reactors, like Essor. The calculation approach concerns the definition of a Weigner-Seitz cell where the loop under examination be subjected to the same neutronic conditions as in the actual reactor

  3. Estimation of water-coal surface interaction during heat treatment of coal by use of FTir and DSC; FTir to DSC wo mochiita sekitan-mizu kan sogo sayo no teiryoteki hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Miura, K.; Mae, K.; Morozumi, F.; Kusakawa, T. [Kyoto University, Kyoto (Japan)

    1997-10-30

    The authors have recently presented a method to estimate the strength distribution of hydrogen bondings in coal using FTir and DSC. The method was applied to estimate the strength of coal-water interaction in two different coals and to estimate the enthalpy change deriving from the change in hydrogen bondings during the desorption of water. The estimated enthalpy change was compared with the total enthalpy change estimated by DSC measurement to examine the importance of hydrogen bondings during the desertion of water. 1 ref., 6 figs.

  4. Computational and experimental methods for enclosed natural convection

    International Nuclear Information System (INIS)

    Larson, D.W.; Gartling, D.K.; Schimmel, W.P. Jr.

    1977-10-01

    Two computational procedures and one optical experimental procedure for studying enclosed natural convection are described. The finite-difference and finite-element numerical methods are developed and several sample problems are solved. Results obtained from the two computational approaches are compared. A temperature-visualization scheme using laser holographic interferometry is described, and results from this experimental procedure are compared with results from both numerical methods

  5. Experimental method for investigating helium effects in irradiated vanadium

    International Nuclear Information System (INIS)

    Smith, D.L.; Matsui, H.; Greenwood, L.; Loomis, B.

    1987-10-01

    Analyses have been performed which indicate that an effective method for experimentally investigating helium effects in neutron irradiated vanadium base alloys can be developed. The experimental procedure involves only modest modifications to existing procedures currently used for irradiation testing of vanadium-base alloys in the FFTF reactor. Helium is generated in the vanadium alloy by decay of tritium which is either preinjected or generated within the test capsule. Calculations indicate that nearly constant He/dpa ratios of desired magnitude can be attained by proper selection of experimental parameters. The proposed method could have a major impact on the development of vanadium base alloys for fusion reactor applications. 8 refs., 4 figs

  6. Temperature-modulated DSC provides new insight about nickel-titanium wire transformations.

    Science.gov (United States)

    Brantley, William A; Iijima, Masahiro; Grentzer, Thomas H

    2003-10-01

    Differential scanning calorimetry (DSC) is a well-known method for investigating phase transformations in nickel-titanium orthodontic wires; the microstructural phases and phase transformations in these wires have central importance for their clinical performance. The purpose of this study was to use the more recently developed technique of temperature-modulated DSC (TMDSC) to gain insight into transformations in 3 nickel-titanium orthodontic wires: Neo Sentalloy (GAC International, Islandia, NY), 35 degrees C Copper Ni-Ti (Ormco, Glendora, Calif) and Nitinol SE (3M Unitek, Monrovia, Calif). In the oral environment, the first 2 superelastic wires have shape memory, and the third wire has superelastic behavior but not shape memory. All wires had cross-section dimensions of 0.016 x 0.022 in. Archwires in the as-received condition and after bending 135 degrees were cut into 5 or 6 segments for test specimens. TMDSC analyses (Model 2910 DSC, TA Instruments, Wilmington, Del) were conducted between -125 degrees C and 100 degrees C, using a linear heating and cooling rate of 2 degrees C per min, an oscillation amplitude of 0.318 degrees C with a period of 60 seconds, and helium as the purge gas. For all 3 wire alloys, strong low-temperature martensitic transformations, resolved on the nonreversing heat-flow curves, were not present on the reversing heat-flow curves, and bending appeared to increase the enthalpy change for these peaks in some cases. For Neo Sentalloy, TMDSC showed that transformation between martensitic and austenitic nickel-titanium, suggested as occurring directly in the forward and reverse directions by conventional DSC, was instead a 2-step process involving the R-phase. Two-step transformations in the forward and reverse directions were also found for 35 degrees C Copper Ni-Ti and Nitinol SE. The TMDSC results show that structural transformations in these wires are complex. Some possible clinical implications of these observations are discussed.

  7. The effects of urea and n-propanol on collagen denaturation: using DSC, circular dicroism and viscosity

    International Nuclear Information System (INIS)

    Usha, R.; Ramasami, T.

    2004-01-01

    The effect of urea and n-propanol on circular dichroism (CD) and viscosity of purified type1 collagen solution at various temperatures and differential scanning calorimetry (DSC) of rat-tail tendon (RTT) collagen fibre have been studied. CD reveals a spectrum with a positive peak at around 220 nm and a negative peak at 200 nm characteristics of collagen triple helix. The molar ellipticity decreases as the concentration of urea increases up to particular concentration (collagen solution treated with 265 μM of urea) and after that it increases (collagen solution treated with 500 μM of urea). There is a linear decrease in molar ellipticity as the concentration of n-propanol increases. Denaturation temperature of urea and n-propanol treated with purified collagen solution has been studied using viscosity method. Additives such as urea and n-propanol decrease the thermal stability of collagen triple helix in solution and in RTT collagen fibre. Thermal helix to coil transition of urea and n-propanol treated collagen depends on the degree of hydration and the concentration of these additives. Thermodynamic parameters such as the peak temperature, enthalpy of activation, and energy of activation for collagen-gelatin transition for native, urea and n-propanol treated RTT collagen fibre has been calculated using DSC. The change in the thermodynamic parameters has been observed for native, urea and n-propanol treated RTT collagen fibres. The experimental results show that the change in the water structure, dehydration and desolvation induced by different additives such as urea and n-propanol on RTT may vary with the type of denaturation

  8. New experimental and analysis methods in I-DLTS

    International Nuclear Information System (INIS)

    Pandey, S.U.; Middelkamp, P.; Li, Z.; Eremin, V.

    1998-02-01

    A new experimental apparatus to perform I-DLTS measurements is presented. The method is shown to be faster and more sensitive than traditional double boxcar I-DLTS systems. A novel analysis technique utilizing multiple exponential fits to the I-DLTS signal from a highly neutron irradiated silicon sample is presented with a discussion of the results. It is shown that the new method has better resolution and can deconvolute overlapping peaks more accurately than previous methods

  9. Experimental Methods for the Analysis of Optimization Algorithms

    DEFF Research Database (Denmark)

    of solution quality, runtime and other measures; and the third part collects advanced methods from experimental design for configuring and tuning algorithms on a specific class of instances with the goal of using the least amount of experimentation. The contributor list includes leading scientists......, computational experiments differ from those in other sciences, and the last decade has seen considerable methodological research devoted to understanding the particular features of such experiments and assessing the related statistical methods. This book consists of methodological contributions on different...

  10. Psychometric Evaluation of the Diabetes Symptom Checklist-Revised (DSC-R)-A Measure of Symptom Distress

    NARCIS (Netherlands)

    Arbuckle, R.A.; Humphrey, L.; Vardeva, K.; Arondekar, B.; Scott, J.A.; Snoek, F.J.

    2009-01-01

    Objective: To assess the psychometric validity, reliability, responsiveness, and minimal important differences of the Diabetes Symptoms Checklist-Revised (DSC-R), a widely used patient-reported outcome measure of diabetes symptom distress. Research Design and Methods: Psychometric validity of the

  11. Experimental Method for Measuring Dust Load on Surfaces in Rooms

    DEFF Research Database (Denmark)

    Lengweiler, Philip; Nielsen, Peter V.; Moser, Alfred

    A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms, there is a n......A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms......, there is a need for better understanding of the mechanism of dust deposition and resuspension. With the presented experimental setup, the dust load on surfaces in a channel can be measured as a function of the environmental and surface conditions and the type of particles under controlled laboratory conditions....

  12. Thermal behavior of biflorin by beans TG and a DSC photovisual system

    Directory of Open Access Journals (Sweden)

    C. F. S. Aragão

    Full Text Available This work proposes thermal characterization, of the biflorine, orto-quinon of Capraria biflora L., through the TG and DSC photovisual data. The thermogravimetric results showed that the decomposition reaction biflorine occurs three steps under air atmosphere, The DSC of biflorin presented five peaks relating to phase transitions. The DSC photovisual system demonstrated changes in biflorin.

  13. STRUCTURAL AND MECHANICAL CHARACTERIZATION OF DEFORMED POLYMER USING CONFOCAL RAMAN MICROSCOPY AND DSC

    Directory of Open Access Journals (Sweden)

    Birgit Neitzel

    2016-02-01

    Full Text Available Polymers have various interesting properties, which depend largely on their inner structure. One way to influence the macroscopic behaviour is the deformation of the polymer chains, which effects the change in microstructure. For analyzing the microstructure of non-deformed and deformed polymer materials, Raman spectroscopy as well as differential scanning calorimetry (DSC were used. In the present study we compare the results for crystallinity measurements of deformed polymers using both methods in order to characterize the differences in micro-structure due to deformation. The study is ongoing, and we present the results of the first tests.

  14. Algorithmic and experimental methods in algebra, geometry, and number theory

    CERN Document Server

    Decker, Wolfram; Malle, Gunter

    2017-01-01

    This book presents state-of-the-art research and survey articles that highlight work done within the Priority Program SPP 1489 “Algorithmic and Experimental Methods in Algebra, Geometry and Number Theory”, which was established and generously supported by the German Research Foundation (DFG) from 2010 to 2016. The goal of the program was to substantially advance algorithmic and experimental methods in the aforementioned disciplines, to combine the different methods where necessary, and to apply them to central questions in theory and practice. Of particular concern was the further development of freely available open source computer algebra systems and their interaction in order to create powerful new computational tools that transcend the boundaries of the individual disciplines involved.  The book covers a broad range of topics addressing the design and theoretical foundations, implementation and the successful application of algebraic algorithms in order to solve mathematical research problems. It off...

  15. Regularization of the double period method for experimental data processing

    Science.gov (United States)

    Belov, A. A.; Kalitkin, N. N.

    2017-11-01

    In physical and technical applications, an important task is to process experimental curves measured with large errors. Such problems are solved by applying regularization methods, in which success depends on the mathematician's intuition. We propose an approximation based on the double period method developed for smooth nonperiodic functions. Tikhonov's stabilizer with a squared second derivative is used for regularization. As a result, the spurious oscillations are suppressed and the shape of an experimental curve is accurately represented. This approach offers a universal strategy for solving a broad class of problems. The method is illustrated by approximating cross sections of nuclear reactions important for controlled thermonuclear fusion. Tables recommended as reference data are obtained. These results are used to calculate the reaction rates, which are approximated in a way convenient for gasdynamic codes. These approximations are superior to previously known formulas in the covered temperature range and accuracy.

  16. Vapour liquid equilibria of monocaprylin plus palmitic acid or methyl stearate at P = (1.20 and 2.50) kPa by using DSC technique

    International Nuclear Information System (INIS)

    Cunico, Larissa P.; Damaceno, Daniela S.; Matricarde Falleiro, Rafael M.; Sarup, Bent; Abildskov, Jens; Ceriani, Roberta; Gani, Rafiqul

    2015-01-01

    Highlights: • Novel VLE data for binary mixtures involving a partial acylglycerol (monocaprylin). • Use of a promising technique for measuring VLE/vapour pressure data (DSC technique). • The consistency of experimental data is analysed by a proposed methodology. • Regressed parameters are given for excess Gibbs thermodynamic models. • New regressed parameters are presented for UNIFAC to account for nonidealities. - Abstract: The Differential Scanning Calorimetry (DSC) technique is used for measuring isobaric (vapour + liquid) equilibria for two binary mixtures: {monocaprylin + palmitic acid (system 1) or methyl stearate (system 2)} at two different pressures P = (1.20 and 2.50) kPa. The obtained PTx data are correlated by Wilson, NRTL and UNIQUAC models. The original UNIFAC group contribution method is also considered and new binary interaction parameters for the main groups CH 2 , CCOO, OH and COOH are regressed, to account for the non-idealities found in these lipid systems. Established thermodynamic consistency tests are applied and attest the quality of the measured data. In terms of relevance of the selected components, system 1 can be found in the purification and deodorization steps during the production of edible oils, while, system 2 can be found in the purification steps of biodiesel. It should be noted that no such data could be found in the open literature, not only for the specific components selected but also for the combination of the classes of components considered; that is, acylglycerol plus fatty acid or fatty ester.

  17. Cerebral perfusion alterations in epileptic patients during peri-ictal and post-ictal phase: PASL vs DSC-MRI.

    Science.gov (United States)

    Pizzini, Francesca B; Farace, Paolo; Manganotti, Paolo; Zoccatelli, Giada; Bongiovanni, Luigi G; Golay, Xavier; Beltramello, Alberto; Osculati, Antonio; Bertini, Giuseppe; Fabene, Paolo F

    2013-07-01

    Non-invasive pulsed arterial spin labeling (PASL) MRI is a method to study brain perfusion that does not require the administration of a contrast agent, which makes it a valuable diagnostic tool as it reduces cost and side effects. The purpose of the present study was to establish the viability of PASL as an alternative to dynamic susceptibility contrast (DSC-MRI) and other perfusion imaging methods in characterizing changes in perfusion patterns caused by seizures in epileptic patients. We evaluated 19 patients with PASL. Of these, the 9 affected by high-frequency seizures were observed during the peri-ictal period (within 5hours since the last seizure), while the 10 patients affected by low-frequency seizures were observed in the post-ictal period. For comparison, 17/19 patients were also evaluated with DSC-MRI and CBF/CBV. PASL imaging showed focal vascular changes, which allowed the classification of patients in three categories: 8 patients characterized by increased perfusion, 4 patients with normal perfusion and 7 patients with decreased perfusion. PASL perfusion imaging findings were comparable to those obtained by DSC-MRI. Since PASL is a) sensitive to vascular alterations induced by epileptic seizures, b) comparable to DSC-MRI for detecting perfusion asymmetries, c) potentially capable of detecting time-related perfusion changes, it can be recommended for repeated evaluations, to identify the epileptic focus, and in follow-up and/or therapy-response assessment. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Overriding "doing wrong" and "not doing right": validation of the Dispositional Self-Control Scale (DSC).

    Science.gov (United States)

    Ein-Gar, Danit; Sagiv, Lilach

    2014-01-01

    We present the Dispositional Self-Control (DSC) Scale, which reflects individuals' tendency to override 2 types of temptations, termed doing wrong and not doing right. We report a series of 5 studies designed to test the reliability and validity of the scale. As hypothesized, high DSC predicts distant future orientation and low DSC predicts deviant behaviors such as aggression, alcohol misuse, and aberrant driving. DSC also predicts task performance among resource-depleted participants. Taken together, these findings suggest that the DSC Scale could be a useful tool toward further understanding the role of personality in overcoming self-control challenges.

  19. 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.

  20. Experimental methods for the analysis of optimization algorithms

    CERN Document Server

    Bartz-Beielstein, Thomas; Paquete, Luis; Preuss, Mike

    2010-01-01

    In operations research and computer science it is common practice to evaluate the performance of optimization algorithms on the basis of computational results, and the experimental approach should follow accepted principles that guarantee the reliability and reproducibility of results. However, computational experiments differ from those in other sciences, and the last decade has seen considerable methodological research devoted to understanding the particular features of such experiments and assessing the related statistical methods. This book consists of methodological contributions on diffe

  1. Testing methods of ECR ion source experimental platform

    International Nuclear Information System (INIS)

    Zhou Changgeng; Hu Yonghong; Li Yan

    2006-12-01

    The principle and structure of ECR ion source experimental platform were introduce. The testing methods of the parameters of single main component and the comprehensive parameters under the condition of certain beam current and beam spot diameter were summarized in process of manufacturing. Some appropriate testing dates were given. The existent questions (the parameters of plasma density in discharge chamber and accurate hydrogen flow, etc. can not be measured in operation) and resolutions were also put forward. (authors)

  2. Sodium cleaning and disposal methods in experimental facilities

    International Nuclear Information System (INIS)

    Rajan, K.K.; Gurumoorthy, K.; Rajan, M.; Kale, R.D.

    1997-01-01

    At Indira Gandhi Centre for Atomic Research, major sodium facilities are designed and operated at Engineering Development Group as a part of development programme towards experimental and Prototype Fast Reactor. After the test programme many equipment and components were removed from the sodium facilities and sodium removal and disposal was carried out. The experience gained in different cleaning methods and waste sodium disposal are discussed. (author)

  3. A DSC analysis of inverse salt-pair explosive composition

    Energy Technology Data Exchange (ETDEWEB)

    Babu, E. Suresh; Kaur, Sukhminder [Central Forensic Science Laboratory, Explosives Division, Ramanthapur, Hyderabad 500013 (India)

    2004-02-01

    Alkali nitrates are used as an ingredient in low explosive compositions and pyrotechnics. It has been suggested that alkali nitrates can form inverse salt-pair explosives with the addition of ammonium chloride. Therefore, the thermal behavior of low explosive compositions containing potassium nitrate mixed with ammonium chloride has been studied using Differential Scanning Calorimetry (DSC). Results provide information about the ion exchange reaction between these two chemical substances and the temperature region at which the formation of a cloud of salt particles of potassium chloride takes place. Furthermore, the addition of ammonium chloride quenches the flame of deflagrating compositions and causes the mixture to undergo explosive decomposition at relatively low temperatures. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  4. DSC analysis of irradiated proteins from Crotalus durissus terrificus

    International Nuclear Information System (INIS)

    Oliveira, Karina Corleto de; Silva, Monica Nascimento da; Goncalves, Karina de Oliveira; Spencer, Patrick Jack; Nascimento, Nanci do

    2011-01-01

    Full text: Snake bites are a serious public health problem, especially in subtropical countries. In Brazil, the serum, the only effective treatment in case of snake bites, is produced in horses which, despite the large size, have a reduced lifespan due to the high toxicity of the antigen. It is known that ionizing radiation effects - direct and indirect - can modify the molecular structure, affecting the biological properties of proteins. Ionizing radiation has been employed to attenuate the toxicity of snake venoms, aiming to generate an improved antigen with low toxicity. Two proteins, purified from Crotalus durissus terrificus (Cdt) venom were tested in this work: crotoxin and crotamine. Crotoxin, the main toxic compound of Cdt venom, is a heterodimeric protein composed of two subunits: crotapotin and phospholipase A2. Crotamine is a highly basic polypeptide (pI - 10.3), with myotoxic activity and molecular weight of 4882 Da. It is composed of 42 amino acids residues and reticulated by three disulfide bonds. This study aimed to investigate the effects of radiation on crotoxin and crotamine using Differential Scanning Calorimetry (DSC). After isolation of the toxins by chromatographic techniques, they were irradiated with 2.0 kGy from 60 Co source. The thermodynamics analysis, carried out in a METTLER TOLEDO, DSC 822e calorimeter, showed that irradiation promoted changes of the calorimetric profile. These changes suggest that, although radiation induced structural modifications of the protein, denaturation was only partial, since transition states could still be detected, suggesting that some structural elements were still present after irradiation. Taken together, our data suggest that following irradiation, the molecules underwent conformational changes, and that the remaining structural elements displayed a lower enthalpy, clearly indicating that the previously described loss of toxicity of irradiated toxins can be mostly ascribed to structural changes

  5. DSC analysis of irradiated proteins from Crotalus durissus terrificus

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Karina Corleto de; Silva, Monica Nascimento da; Goncalves, Karina de Oliveira; Spencer, Patrick Jack; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Full text: Snake bites are a serious public health problem, especially in subtropical countries. In Brazil, the serum, the only effective treatment in case of snake bites, is produced in horses which, despite the large size, have a reduced lifespan due to the high toxicity of the antigen. It is known that ionizing radiation effects - direct and indirect - can modify the molecular structure, affecting the biological properties of proteins. Ionizing radiation has been employed to attenuate the toxicity of snake venoms, aiming to generate an improved antigen with low toxicity. Two proteins, purified from Crotalus durissus terrificus (Cdt) venom were tested in this work: crotoxin and crotamine. Crotoxin, the main toxic compound of Cdt venom, is a heterodimeric protein composed of two subunits: crotapotin and phospholipase A2. Crotamine is a highly basic polypeptide (pI - 10.3), with myotoxic activity and molecular weight of 4882 Da. It is composed of 42 amino acids residues and reticulated by three disulfide bonds. This study aimed to investigate the effects of radiation on crotoxin and crotamine using Differential Scanning Calorimetry (DSC). After isolation of the toxins by chromatographic techniques, they were irradiated with 2.0 kGy from {sup 60}Co source. The thermodynamics analysis, carried out in a METTLER TOLEDO, DSC 822e calorimeter, showed that irradiation promoted changes of the calorimetric profile. These changes suggest that, although radiation induced structural modifications of the protein, denaturation was only partial, since transition states could still be detected, suggesting that some structural elements were still present after irradiation. Taken together, our data suggest that following irradiation, the molecules underwent conformational changes, and that the remaining structural elements displayed a lower enthalpy, clearly indicating that the previously described loss of toxicity of irradiated toxins can be mostly ascribed to structural changes

  6. Improving a variation of the DSC technique for measuring the boiling points of pure compounds at low pressures

    International Nuclear Information System (INIS)

    Troni, Kelly L.; Damaceno, Daniela S.; Ceriani, Roberta

    2016-01-01

    Highlights: • Improvement of a variation of the DSC technique for boiling points at low pressures. • Use of a ballpoint pen ball over the pinhole of the DSC crucible. • Effects of configuration variables of the DSC technique accounted by factorial design. • An optimized region was obtained and tested for selected compounds. - Abstract: This study aims to improve a variation of the differential scanning calorimetry (DSC) technique for measuring boiling points of pure compounds at low pressures. Using a well-known n-paraffin (n-hexadecane), experimental boiling points at a pressure of 3.47 kPa with u(P) = 0.07 kPa were obtained by using a variation of the DSC technique, which consists of placing samples inside hermetically sealed aluminum crucibles, with a pinhole (diameter of 0.8 mm) made on the lid and a tungsten carbide ball with a diameter of 1.0 mm over it. Experiments were configured at nine different combinations of heating rates (K·min"−"1) and sample sizes (mg) following a full factorial design (2"2 trials plus a star configuration and three central points). Individual and combined effects of these two independent variables on the difference between experimental and estimated boiling points (NIST Thermo Data Engine v. 5.0 – Aspen Plus v. 8.4) were investigated. The results obtained in this work reveal that although both factors affect individually the accuracy of this variation of the DSC technique, the effect of heating rate is the most important. An optimized region of combinations of heating rate and sample size for determining boiling points of pure compounds at low pressures was obtained using the response-surface methodology (RSM). Within this optimized region, a selected condition, combining a heating rate of 24.52 K·min"−"1 and a sample size of (4.6 ± 0.5) mg, was tested for six different compounds (92.094–302.37 g mol"−"1) comprising four fatty compounds (tributyrin, monocaprylin, octanoic acid and 1-octadecanol), glycerol and n

  7. An experimental method of characterization of deformable porous media

    Directory of Open Access Journals (Sweden)

    Sommier Alain

    2012-04-01

    Full Text Available A porous medium saturated with liquid and placed within a medium that undergoes a change in pressure reacts by shrinking. If the space contains the same liquid as the pores of the sample, then after a certain lapse of time the sample dilates. By measuring this dilation kinetic the specimen’s permeability can be approximated. This experimental method is called Dynamic Pressurisation. We set up an experimental apparatus to measure the permeability and the different agarose gel compressibility moduli. The liquid contained inside the gel pores is water. We have realized experiments in water and others in oil. In Scherer’s method the flow is considered only in the radial direction. To find the real permeability value we have built a numerical model considering that both the liquid and the solid are compressible. The simulations were compared to the experimental results and have allowed finding the real value of the permeability by considering the flow in both radial and axial directions.

  8. Experimental method for testing diffraction properties of reflection waveguide holograms.

    Science.gov (United States)

    Xie, Yi; Kang, Ming-Wu; Wang, Bao-Ping

    2014-07-01

    Waveguide holograms' diffraction properties include peak wavelength and diffraction efficiency, which play an important role in determining their display performance. Based on the record and reconstruction theory of reflection waveguide holograms, a novel experimental method for testing diffraction properties is introduced and analyzed in this paper, which uses a plano-convex lens optically contacted to the surface of the substrate plate of the waveguide hologram, so that the diffracted light beam can be easily detected. Then an experiment is implemented. The designed reconstruction wavelength of the test sample is 530 nm, and its diffraction efficiency is 100%. The experimental results are a peak wavelength of 527.7 nm and a diffraction efficiency of 94.1%. It is shown that the tested value corresponds well with the designed value.

  9. Experimental Methods for the Analysis of Optimization Algorithms

    DEFF Research Database (Denmark)

    , computational experiments differ from those in other sciences, and the last decade has seen considerable methodological research devoted to understanding the particular features of such experiments and assessing the related statistical methods. This book consists of methodological contributions on different...... in algorithm design, statistical design, optimization and heuristics, and most chapters provide theoretical background and are enriched with case studies. This book is written for researchers and practitioners in operations research and computer science who wish to improve the experimental assessment......In operations research and computer science it is common practice to evaluate the performance of optimization algorithms on the basis of computational results, and the experimental approach should follow accepted principles that guarantee the reliability and reproducibility of results. However...

  10. An experimental design method leading to chemical Turing patterns.

    Science.gov (United States)

    Horváth, Judit; Szalai, István; De Kepper, Patrick

    2009-05-08

    Chemical reaction-diffusion patterns often serve as prototypes for pattern formation in living systems, but only two isothermal single-phase reaction systems have produced sustained stationary reaction-diffusion patterns so far. We designed an experimental method to search for additional systems on the basis of three steps: (i) generate spatial bistability by operating autoactivated reactions in open spatial reactors; (ii) use an independent negative-feedback species to produce spatiotemporal oscillations; and (iii) induce a space-scale separation of the activatory and inhibitory processes with a low-mobility complexing agent. We successfully applied this method to a hydrogen-ion autoactivated reaction, the thiourea-iodate-sulfite (TuIS) reaction, and noticeably produced stationary hexagonal arrays of spots and parallel stripes of pH patterns attributed to a Turing bifurcation. This method could be extended to biochemical reactions.

  11. DSC and TMA studies on freezing and thawing gelation of galactomannan polysaccharide

    International Nuclear Information System (INIS)

    Iijima, Mika; Hatakeyama, Tatsuko; Hatakeyama, Hyoe

    2012-01-01

    Research highlights: ► Locust bean gum forms hydrogels by freezing and thawing. ► Syneresis was observed when freezing and thawing cycle (n) increased. ► Dynamic Young's modulus increased with increasing n. ► Non-freezing water content restrained by hydrogels decreased with increasing n. ► Strong gel with densely packed network structure formed with increasing n. - Abstract: Among various kinds of polysaccharides known to form hydrogels, locust bean gum (LBG) consisting of a mannose backbone and galactose side chains has unique characteristics, since LBG forms hydrogels by freezing and thawing. In this study, effect of thermal history on gelation was investigated by differential scanning calorimetry (DSC) and thermomechanical analysis (TMA). Gel/sol ratio calculated by weighing method was found to be affected by sol concentration, freezing rate and the number of freezing and thawing cycle (n). Once LBG hydrogels are formed, they are thermally stable, although syneresis was observed when n increased. Dynamic Young's modulus (E′) of hydrogels measured by TMA in water increased with increasing n and decreasing freezing rate. Non-freezing water calculated from DSC melting peak of ice in the gel decreased with increasing n and decreasing freezing rate. Morphological observation of freeze-dried gels was carried out by scanning electron microscopy (SEM). The above results indicate that weak hydrogel having large molecular network structure transformed into strong gel with densely packed network structure by increasing n and decreasing freezing rate.

  12. Comparison between DSC and TMDSC in the investigation into frozen aqueous cryoprotectants solutions.

    Science.gov (United States)

    Santoveña, A; Piñero, M J; Llabrés, M

    2010-12-01

    The influence of thermal parameters in the observation of thermal events and in the calculation of heat transformation in aqueous cryoprotectant solutions after freezing was investigated using conventional differential scanning calorimetry (DSC) and temperature-modulated DSC (TMDSC), respectively. The systems under study were formed by pure water and diluted aqueous solutions of mannitol, trehalose, sucrose, sorbitol, and glycine. The influence of different combinations of frequency and amplitude was analyzed in heating-cooling and heating-iso TMDSC scans. Trehalose, sucrose, and sorbitol present a lesser critical temperature of primary drying than other cryoprotectants studied. The calorimetric variables selection is crucial to detect or not the thermal events, or to detect so with different numerical values. Then, the values of the calorimetric parameters determined are different if measured in a mode of heating-cooling or heating-iso. The TMDSC method-1 used in this study employs a higher number of cycles in each thermal event. The use of Lissajous figures and the study of the C(p in-phase) signal evolution will allow us to understand the complexity of the events detected. The comparative study of both techniques points to the selection of conventional or modulated technique depending on the type of system and the nature of the studied events.

  13. Design and long-term monitoring of DSC/CIGS tandem solar module

    International Nuclear Information System (INIS)

    Vildanova, M F; Nikolskaia, A B; Kozlov, S S; Shevaleevskiy, O I

    2015-01-01

    This paper describes the design and development of tandem dye-sensitized/Cu(In, Ga)Se (DSC/CIGS) PV modules. The tandem PV module comprised of the top DSC module and a bottom commercial 0,8 m 2 CIGS module. The top DSC module was made of 10 DSC mini-modules with the field size of 20 × 20 cm 2 each. Tandem DSC/CIGS PV modules were used for providing the long-term monitoring of energy yield and electrical parameters in comparison with standalone CIGS modules under outdoor conditions. The outdoor test facility, containing solar modules of both types and a measurement unit, was located on the roof of the Institute of Biochemical Physics in Moscow. The data obtained during monitoring within the 2014 year period has shown the advantages of the designed tandem DSC/CIGS PV-modules over the conventional CIGS modules, especially for cloudy weather and low-intensity irradiation conditions. (paper)

  14. Advances in simultaneous DSC-FTIR microspectroscopy for rapid solid-state chemical stability studies: some dipeptide drugs as examples.

    Science.gov (United States)

    Lin, Shan-Yang; Wang, Shun-Li

    2012-04-01

    The solid-state chemistry of drugs has seen growing importance in the pharmaceutical industry for the development of useful API (active pharmaceutical ingredients) of drugs and stable dosage forms. The stability of drugs in various solid dosage forms is an important issue because solid dosage forms are the most common pharmaceutical formulation in clinical use. In solid-state stability studies of drugs, an ideal accelerated method must not only be selected by different complicated methods, but must also detect the formation of degraded product. In this review article, an analytical technique combining differential scanning calorimetry and Fourier-transform infrared (DSC-FTIR) microspectroscopy simulates the accelerated stability test, and simultaneously detects the decomposed products in real time. The pharmaceutical dipeptides aspartame hemihydrate, lisinopril dihydrate, and enalapril maleate either with or without Eudragit E were used as testing examples. This one-step simultaneous DSC-FTIR technique for real-time detection of diketopiperazine (DKP) directly evidenced the dehydration process and DKP formation as an impurity common in pharmaceutical dipeptides. DKP formation in various dipeptides determined by different analytical methods had been collected and compiled. Although many analytical methods have been applied, the combined DSC-FTIR technique is an easy and fast analytical method which not only can simulate the accelerated drug stability testing but also at the same time enable to explore phase transformation as well as degradation due to thermal-related reactions. This technique offers quick and proper interpretations. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Nucleation in As2Se3 glass studied by DSC

    International Nuclear Information System (INIS)

    Svoboda, Roman; Málek, Jiří

    2014-01-01

    Highlights: • Nucleation behavior of As 2 Se 3 glass was studied by DSC in dependence on particle size. • Correlation between the enthalpies of fusion and crystallization were confirmed. • Apart from classical heterogeneous nucleation a second nucleation mechanism was found. • Rapid formation of crystallization centers from a damaged glassy structure occurs. • Mechanical defects seem to partially suppress the CNT nucleation process. - Abstract: Differential scanning calorimetry was used to study nucleation behavior in As 2 Se 3 glass, dependent on particle size. The nucleation process was examined for a series of different coarse powders; the nucleation rate was estimated from the proportion of the crystalline material fraction. The enthalpy of fusion was utilized in this respect, and a correlation between ΔH m and ΔH c was confirmed. Two mechanisms of nucleus formation were found: classical heterogeneous nucleation (following CNT) and so-called “activation” of mechanically-induced defects. The latter appears to represent rapid formation of crystallization centers from a damaged glassy structure, where complete saturation occurs for fine powders in the range of 195–235 °C. A high amount of mechanical defects, on the other hand, was found to partially suppress the CNT nucleation process

  16. Literature in Focus: Statistical Methods in Experimental Physics

    CERN Multimedia

    2007-01-01

    Frederick James was a high-energy physicist who became the CERN "expert" on statistics and is now well-known around the world, in part for this famous text. The first edition of Statistical Methods in Experimental Physics was originally co-written with four other authors and was published in 1971 by North Holland (now an imprint of Elsevier). It became such an important text that demand for it has continued for more than 30 years. Fred has updated it and it was released in a second edition by World Scientific in 2006. It is still a top seller and there is no exaggeration in calling it «the» reference on the subject. A full review of the title appeared in the October CERN Courier.Come and meet the author to hear more about how this book has flourished during its 35-year lifetime. Frederick James Statistical Methods in Experimental Physics Monday, 26th of November, 4 p.m. Council Chamber (Bldg. 503-1-001) The author will be introduced...

  17. Method to deterministically study photonic nanostructures in different experimental instruments.

    Science.gov (United States)

    Husken, B H; Woldering, L A; Blum, C; Vos, W L

    2009-01-01

    We describe an experimental method to recover a single, deterministically fabricated nanostructure in various experimental instruments without the use of artificially fabricated markers, with the aim to study photonic structures. Therefore, a detailed map of the spatial surroundings of the nanostructure is made during the fabrication of the structure. These maps are made using a series of micrographs with successively decreasing magnifications. The graphs reveal intrinsic and characteristic geometric features that can subsequently be used in different setups to act as markers. As an illustration, we probe surface cavities with radii of 65 nm on a silica opal photonic crystal with various setups: a focused ion beam workstation; a scanning electron microscope (SEM); a wide field optical microscope and a confocal microscope. We use cross-correlation techniques to recover a small area imaged with the SEM in a large area photographed with the optical microscope, which provides a possible avenue to automatic searching. We show how both structural and optical reflectivity data can be obtained from one and the same nanostructure. Since our approach does not use artificial grids or markers, it is of particular interest for samples whose structure is not known a priori, like samples created solely by self-assembly. In addition, our method is not restricted to conducting samples.

  18. Experimental facility and void fraction calibration methods for impedance probes

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Fernando L. de; Rocha, Marcelo S., E-mail: floliveira@ipen.br, E-mail: msrocha@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    An experimental facility was designed and constructed with aims of to calibrate a capacitance probe for gas-liquid flow void fraction measurements. The facility is composed of a metallic hack with a vertical 2,300 mm high glass tube with 38 mm ID with stagnant water and compressed air bubbling system simulating the gas phase (vapor). At the lower part, a mixing section with a porous media element releases the air bubbles into the water, and the compressed air flow is measured by two calibrated rotameters. At the upper part a stagnant water tank separates the liquid and gas. Two pressure taps are located near the lower and upper sides of the glass tube for pressure difference measurement. The pressure difference is used for low void fraction values (0-15%) calibration methods, as described in the work. Two electrically controlled quick closing valves are installed between the porous media element and the upward separation tank for high void fraction values measurement (15-50%) used to calibrate the capacitance probe. The experimental facility design, construction, capacitance probe calibration methods and results, as well as flow pattern visualization, are presented. Finally, the capacitance probe will be installed on a natural circulation circuit mounted at the Nuclear Engineering Center (CEN/IPEN/CNEN-SP) for measurement of the instantaneous bulk void. Instantaneous signals generated by the capacitance probe will allow the determination of natural circulation loop global energy balance. (author)

  19. Experimental facility and void fraction calibration methods for impedance probes

    International Nuclear Information System (INIS)

    Oliveira, Fernando L. de; Rocha, Marcelo S.

    2013-01-01

    An experimental facility was designed and constructed with aims of to calibrate a capacitance probe for gas-liquid flow void fraction measurements. The facility is composed of a metallic hack with a vertical 2,300 mm high glass tube with 38 mm ID with stagnant water and compressed air bubbling system simulating the gas phase (vapor). At the lower part, a mixing section with a porous media element releases the air bubbles into the water, and the compressed air flow is measured by two calibrated rotameters. At the upper part a stagnant water tank separates the liquid and gas. Two pressure taps are located near the lower and upper sides of the glass tube for pressure difference measurement. The pressure difference is used for low void fraction values (0-15%) calibration methods, as described in the work. Two electrically controlled quick closing valves are installed between the porous media element and the upward separation tank for high void fraction values measurement (15-50%) used to calibrate the capacitance probe. The experimental facility design, construction, capacitance probe calibration methods and results, as well as flow pattern visualization, are presented. Finally, the capacitance probe will be installed on a natural circulation circuit mounted at the Nuclear Engineering Center (CEN/IPEN/CNEN-SP) for measurement of the instantaneous bulk void. Instantaneous signals generated by the capacitance probe will allow the determination of natural circulation loop global energy balance. (author)

  20. Determination of the glass transition temperature: methods correlation and structural heterogeneity

    OpenAIRE

    Hutchinson, John M.

    2009-01-01

    The definition of the glass transition temperature, Tg, is recalled and its experimental determination by various techniques is reviewed. The diversity of values of Tg obtained by the different methods is discussed, with particular attention being paid to Differential Scanning Calorimetry (DSC) and to dynamic techniques such as Dynamic Mechanical Thermal Analysis (DMTA) and Temperature Modulated DSC (TMDSC). This last technique, TMDSC, in particular, is considered in respect of ways in which ...

  1. Experimental research on intraocular aqueous flow by PIV method.

    Science.gov (United States)

    Yang, Hongyu; Song, Hongfang; Mei, Xi; Li, Lin; Fu, Xineng; Zhang, Mindi; Liu, Zhicheng

    2013-10-21

    Aqueous humor flows regularly from posterior chamber to anterior chamber, and this flow much involves intraocular pressure, the eye tissue nutrition and metabolism. To visualize and measure the intraocular flow regular pattern of aqueous humor. Intraocular flow in the vitro eyeball is driven to simulate the physiological aqueous humor flow, and the flow field is measured by Particle Image Velocimetry(PIV). Fluorescent particle solution of a certain concentration was infused into the root of Posterior Chamber(PC) of vitro rabbit eye to simulate the generation of aqueous and was drained out at a certain hydrostatic pressure from the angle of Anterior Chamber(AC) to represent the drainage of aqueous. PIV method was used to record and calculate the flow on the midsagittal plane of the eyeball. Velocity vector distribution in AC has been obtained, and the distribution shows symmetry feature to some extent. Fluorescent particle solution first fills the PC as it is continuously infused, then surges into AC through the pupil, flows upwards toward the central cornea, reflecting and scattering, and eventually converges along the inner cornea surface towards the outflow points at the periphery of the eyeball. Velocity values around the pupillary margin are within the range of 0.008-0.012 m/s, which are close to theoretical values of 0.0133 m/s, under the driving rate of 100 μl/min. Flow field of aqueous humor can be measured by PIV method, which makes it possible to study the aqueous humor dynamics by experimental method. Our study provides a basis for experimental research on aqueous humor flow; further, it possibly helps to diagnose and treat eye diseases as shear force damage of ocular tissues and destructions on corneal endothelial cells from the point of intraocular flow field.

  2. Experimental study of self-backlighting method for opacity

    International Nuclear Information System (INIS)

    Ding Yaonan; Yang Jiamin; Li Sanwei; Cao Leifeng; Wang Yaomei; Zhang Wenhai; Chen Bo; Yu Yanning; Wang Hongbin

    2001-01-01

    Self-backlighting method for opacity measurement has been suggested and studied, based on the actual condition of Xingguang II laser facility. An 80 J and 350 nm laser, which has a duration of about 700 ps, irradiates on a newly designed target and creates intense X-ray radiation acting as both heating source and backlighter source. The heated sample has been spatially imaged to obtain X-ray spectra from X-ray source region, transmission region and self-emission region of the sample at the same shot by spatially resolved transmission grating spectrometer in which dispersed X-ray is recorded by X-ray CCD. The samples are low-Z CH foam with density of 0.042 g/cm 3 , thickness of 42 μm and mid-Z Al with density of 2.7 g/cm 3 , thickness of 0.5 μm or 1.0 μm. Mass absorption coefficients of the heated sample as function of the photon energy have been obtained experimentally in the same shot. The spectra line emitted from the heated CH foam has also been measured by OHM crystal spectrometer, which has been used to determine the temperature of the sample. The experimental results for opacity of carbon have been discussed

  3. Experimentally aided development of a turbine heat transfer prediction method

    International Nuclear Information System (INIS)

    Forest, A.E.; White, A.J.; Lai, C.C.; Guo, S.M.; Oldfield, M.L.G.; Lock, G.D.

    2004-01-01

    In the design of cooled turbomachinery blading a central role is played by the computer methods used to optimise the aerodynamic and thermal performance of the turbine aerofoils. Estimates of the heat load on the turbine blading should be as accurate as possible, in order that adequate life may be obtained with the minimum cooling air requirement. Computer methods are required which are able to model transonic flows, which are a mixture of high temperature combustion gases and relatively cool air injected through holes in the aerofoil surface. These holes may be of complex geometry, devised after empirical studies of the optimum shape and the most cost effective manufacturing technology. The method used here is a further development of the heat transfer design code (HTDC), originally written by Rolls-Royce plc under subcontract to Rolls-Royce Inc for the United States Air Force. The physical principles of the modelling employed in the code are explained without extensive mathematical details. The paper describes the calibration of the code in conjunction with a series of experimental measurements on a scale model of a high-pressure nozzle guide vane at non-dimensionally correct engine conditions. The results are encouraging, although indicating that some further work is required in modelling highly accelerated pressure surface flow

  4. An experimental method for designing the municipal solid waste biodrying

    International Nuclear Information System (INIS)

    Rada, E.C.; Politecnico Univ., Bucarest; Franzinelli, A.; Taiss, M.; Ragazzi, M.; Panaitescu, V.; Apostol, T.

    2005-01-01

    In the management of Municipal Solid Waste (MSW), in agreement with the new European directives concerning the valorization of materials and energy recovery, a recent approach based on a one-stream Biological Mechanical Treatment (BMT) is spreading as an alternative to the traditional two-stream approach. The bio-mechanical treatment of MSW is an increasing option either as a pre-treatment before land filling or as a pre-treatment before combustion. In the present paper an experimental method for designing the Municipal Solid Waste bio-drying is proposed. That means this paper deals with the option of energy recovery. The aim is to provide design criteria for bio-drying plants independent from the patents available in the sector [it

  5. Experimental Methods for UAV Aerodynamic and Propulsion Performance Assessment

    Directory of Open Access Journals (Sweden)

    Stefan ANTON

    2015-06-01

    Full Text Available This paper presents an experimental method for assessing the performances and the propulsion power of a UAV in several points based on telemetry. The points in which we make the estimations are chosen based on several criteria and the fallowing parameters are measured: airspeed, time-to-climb, altitude and the horizontal distance. With the estimated propulsion power and knowing the shaft motor power, the propeller efficiency is determined at several speed values. The shaft motor power was measured in the lab using the propeller as a break. Many flights, using the same UAV configuration, were performed before extracting flight data, in order to reduce the instrumental or statistic errors. This paper highlights both the methodology of processing the data and the validation of theoretical results.

  6. Experimental and Theoretical Methods in Algebra, Geometry and Topology

    CERN Document Server

    Veys, Willem; Bridging Algebra, Geometry, and Topology

    2014-01-01

    Algebra, geometry and topology cover a variety of different, but intimately related research fields in modern mathematics. This book focuses on specific aspects of this interaction. The present volume contains refereed papers which were presented at the International Conference “Experimental and Theoretical Methods in Algebra, Geometry and Topology”, held in Eforie Nord (near Constanta), Romania, during 20-25 June 2013. The conference was devoted to the 60th anniversary of the distinguished Romanian mathematicians Alexandru Dimca and Ştefan Papadima. The selected papers consist of original research work and a survey paper. They are intended for a large audience, including researchers and graduate students interested in algebraic geometry, combinatorics, topology, hyperplane arrangements and commutative algebra. The papers are written by well-known experts from different fields of mathematics, affiliated to universities from all over the word, they cover a broad range of topics and explore the research f...

  7. 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)

  8. The experimental field work as practical learning method

    Directory of Open Access Journals (Sweden)

    Nicolás Fernández Losa

    2014-11-01

    Full Text Available This paper describes a teaching experience about experimental field work as practical learning method implemented in the subject of Organizational Behaviour. With this teaching experience we pretend to change the practical training, as well as in its evaluation process, in order to favour the development of transversal skills of students. For this purpose, the use of a practice plan, tackled through an experimental field work and carried out with the collaboration of a business organization within a work team (as organic unity of learning, arises as an alternative to the traditional method of practical teachings and allows the approach of business reality into the classroom, as well as actively promote the use of transversal skills. In particular, we develop the experience in three phases. Initially, the students, after forming a working group and define a field work project, should get the collaboration of a nearby business organization in which to obtain data on one or more functional areas of organizational behaviour. Subsequently, students carry out the field work with the realization of the scheduled visits and elaboration of a memory to establish a diagnosis of the strategy followed by the company in these functional areas in order to propose and justify alternative actions that improve existing ones. Finally, teachers assess the different field work memories and their public presentations according to evaluation rubrics, which try to objectify and unify to the maximum the evaluation criteria and serve to guide the learning process of students. The results of implementation of this teaching experience, measured through a Likert questionnaire, are very satisfactory for students.

  9. Thermodynamic optimization of individual steel database by means of systematic DSC measurements according the CALPHAD approach

    International Nuclear Information System (INIS)

    Presoly, P; Bernhard, C; Six, J

    2016-01-01

    Reliable thermodynamic data are essential information required for the design of new steel types and are a prerequisite to effective process optimization and simulation. Moreover, it is important to know the exact temperatures at which the high-temperature phase transformations (T Liquid , T Solid , T Perit , T γ→δ ) occur in order to describe the solidification sequence and to describe further processing parameters. By utilizing DTA/DSC measurements, our earlier experimental studies of selected commercial DP, TRIP and high-Mn TWIP steels, have indicated that currently commercially available databases can often not be utilised to reliably describe the behaviour and microstructural development in such complex alloy systems. Because of these ostensible deficiencies, an experimental study was undertaken in an attempt to determine the pertaining thermodynamic data to analyse the behaviour of the important five- component Fe-C-Si-Mn-Al alloy system. High purity model alloys with systematic alloy variations were prepared and utilized in order to determine the influence of individual alloying elements in this complex, but industrially important alloy system. The present study provides new validated experimental thermodynamic data and analysis of the five-component Fe-C-Si- Mn-Al system, which will allow the construction of new phase diagrams, prediction of solidification sequences and the assessment of micro-segregation. (paper)

  10. Thermodynamic optimization of individual steel database by means of systematic DSC measurements according the CALPHAD approach

    Science.gov (United States)

    Presoly, P.; Six, J.; Bernhard, C.

    2016-03-01

    Reliable thermodynamic data are essential information required for the design of new steel types and are a prerequisite to effective process optimization and simulation. Moreover, it is important to know the exact temperatures at which the high-temperature phase transformations (TLiquid, TSolid, TPerit, Tγ→δ) occur in order to describe the solidification sequence and to describe further processing parameters. By utilizing DTA/DSC measurements, our earlier experimental studies of selected commercial DP, TRIP and high-Mn TWIP steels, have indicated that currently commercially available databases can often not be utilised to reliably describe the behaviour and microstructural development in such complex alloy systems. Because of these ostensible deficiencies, an experimental study was undertaken in an attempt to determine the pertaining thermodynamic data to analyse the behaviour of the important five- component Fe-C-Si-Mn-Al alloy system. High purity model alloys with systematic alloy variations were prepared and utilized in order to determine the influence of individual alloying elements in this complex, but industrially important alloy system. The present study provides new validated experimental thermodynamic data and analysis of the five-component Fe-C-Si- Mn-Al system, which will allow the construction of new phase diagrams, prediction of solidification sequences and the assessment of micro-segregation.

  11. A Differential Scanning Calorimetry Method for Construction of Continuous Cooling Transformation Diagram of Blast Furnace Slag

    Science.gov (United States)

    Gan, Lei; Zhang, Chunxia; Shangguan, Fangqin; Li, Xiuping

    2012-06-01

    The continuous cooling crystallization of a blast furnace slag was studied by the application of the differential scanning calorimetry (DSC) method. A kinetic model describing the correlation between the evolution of the degree of crystallization with time was obtained. Bulk cooling experiments of the molten slag coupled with numerical simulation of heat transfer were conducted to validate the results of the DSC methods. The degrees of crystallization of the samples from the bulk cooling experiments were estimated by means of the X-ray diffraction (XRD) and the DSC method. It was found that the results from the DSC cooling and bulk cooling experiments are in good agreement. The continuous cooling transformation (CCT) diagram of the blast furnace slag was constructed according to crystallization kinetic model and experimental data. The obtained CCT diagram characterizes with two crystallization noses at different temperature ranges.

  12. Rheological and DSC study of sol-gel transition in aqueous dispersions of industrially important polymers and colloids

    Energy Technology Data Exchange (ETDEWEB)

    Nishinari, K. [Osaka City Univ. (Japan). Dept. of Food and Nutrition

    1997-12-01

    Gelation kinetics, mechanical spectra, thermal scanning rheology (TSR), and differential scanning calorimetry (DSC) in aqueous solutions of gelling polymers and colloids such as seaweed polysaccharides (agarose, carrageenans), microbial polysaccharides (gellan, curdlan), plant polysaccharides (methylcellulose), globular proteins (casein, glycinin, {beta}-conglycinin), fibrous proteins (gelatin, fibrin), and polyvinyl alcohol, which are related to foods, cosmetics, biomedical and pharmaceutical applications, are described. Some gelation processes at a constant temperature have been treated successfully by an equation of first order kinetics or by other modified equations, and the molecular mechanism of gel formation is discussed briefly. For water-soluble polymers, the criterion of the gel or sol based on the frequency dependence of storage and loss moduli gives valuable informations. TSR and DSC are complementary, and the combination of these methods has been proved to be useful. (orig.) 81 refs.

  13. Pengaruh pengawetan kulit ikan buntal (Arothon reticularis terhadap suhu kerut ditinjau melalui analisis differential scanning calorimeter (DSC

    Directory of Open Access Journals (Sweden)

    RLM. Satrio Ari Wibowo

    2015-12-01

    Full Text Available The aim of this study was to determine the effect of the skin preservation type against shrinkage temperature of leather. The material used in this study was the skin of pufferfish (Arothon reticularis that have been preserved by salting, formaldehyde and pickling and also raw skin as a reference. The method used to measure the shrinkage temperature was thermal analysis using Differential Scanning Calorimeter (DSC that operated from 4°C up to 440°C with nitrogen stream. DSC measurement results showed that shrinkage temperature of puffer fish preserved with formaldehyde was higher than salting and pickling, which is 63.64°C; 47.95°C; 57.37oC respectively. The advantage of using formaldehyde compared to others preservation technique was not only can protect the skin from damage by microorganisms, but also can create a bond with the collagen .

  14. DSC and curing kinetics study of epoxy grouting diluted with furfural -acetone slurry

    Science.gov (United States)

    Yin, H.; Sun, D. W.; Li, B.; Liu, Y. T.; Ran, Q. P.; Liu, J. P.

    2016-07-01

    The use of furfural-acetone slurry as active diluents of Bisphenol-A epoxy resin (DGEBA) groutings has been studied by dynamic and non-isothermal DSC for the first time. Curing kinetics study was investigated by non-isothermal differential scanning calorimetries at different heating rates. Activation enery (Ea) was calculated based on Kissinger and Ozawa Methods, and the results showed that Ea increased from 58.87 to 71.13KJ/mol after the diluents were added. The furfural-acetone epoxy matrix could cure completely at the theoretical curing temperature of 365.8K and the curing time of 139mins, which were determined by the kinetic model parameters.

  15. A projection method for under determined optimal experimental designs

    KAUST Repository

    Long, Quan; Scavino, Marco; Tempone, Raul; Wang, Suojin

    2014-01-01

    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.

  16. 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.

  17. Experimental determination of dynamic fracture toughness by J integral method

    International Nuclear Information System (INIS)

    Marandel, B.; Phelippeau, G.; Sanz, G.

    1982-01-01

    Fracture toughness tests are conducted on fatigue precracked compact tension specimens (IT - CT) loaded at K rates of about 2 x 10 4 MPa square root of m/s on a servo-hydraulic machine using a damped set-up. A high frequency alternating current system (10 kHz) is used for the detection of subcritical crack growth during loading. The analog signals from the clip gage, load cell, ram travel and potential drop system are fed into a magnetic tape recorder, filtered and converted to digital data. Load-time and load-displacement-potential curves are plotted and analysed automatically by two different methods, according to the fracture mode: in the lower part of the transition curve, Ksub(ID) is calculated from the maximum load at failure in the linear elastic range (ASTM E399); in the transition and upper shelf regions, Ksub(JD) is calculated from Jsub(ID) at initiation of ductile crack growth in the elastic plastic range. The experimental method described here is applied, as an example, to the study of a low-alloy, medium strength pressure vessel steel (A 508 Cl.3). A comparison is established between the toughness transition curves obtained under quasi-static (Ksub(Jc)) and dynamic (Ksub(JD)) conditions. (author)

  18. Optical bandgap of semiconductor nanostructures: Methods for experimental data analysis

    Science.gov (United States)

    Raciti, R.; Bahariqushchi, R.; Summonte, C.; Aydinli, A.; Terrasi, A.; Mirabella, S.

    2017-06-01

    Determination of the optical bandgap (Eg) in semiconductor nanostructures is a key issue in understanding the extent of quantum confinement effects (QCE) on electronic properties and it usually involves some analytical approximation in experimental data reduction and modeling of the light absorption processes. Here, we compare some of the analytical procedures frequently used to evaluate the optical bandgap from reflectance (R) and transmittance (T) spectra. Ge quantum wells and quantum dots embedded in SiO2 were produced by plasma enhanced chemical vapor deposition, and light absorption was characterized by UV-Vis/NIR spectrophotometry. R&T elaboration to extract the absorption spectra was conducted by two approximated methods (single or double pass approximation, single pass analysis, and double pass analysis, respectively) followed by Eg evaluation through linear fit of Tauc or Cody plots. Direct fitting of R&T spectra through a Tauc-Lorentz oscillator model is used as comparison. Methods and data are discussed also in terms of the light absorption process in the presence of QCE. The reported data show that, despite the approximation, the DPA approach joined with Tauc plot gives reliable results, with clear advantages in terms of computational efforts and understanding of QCE.

  19. Implementation of DSC model and application for analysis of field pile tests under cyclic loading

    Science.gov (United States)

    Shao, Changming; Desai, Chandra S.

    2000-05-01

    The disturbed state concept (DSC) model, and a new and simplified procedure for unloading and reloading behavior are implemented in a nonlinear finite element procedure for dynamic analysis for coupled response of saturated porous materials. The DSC model is used to characterize the cyclic behavior of saturated clays and clay-steel interfaces. In the DSC, the relative intact (RI) behavior is characterized by using the hierarchical single surface (HISS) plasticity model; and the fully adjusted (FA) behavior is modeled by using the critical state concept. The DSC model is validated with respect to laboratory triaxial tests for clay and shear tests for clay-steel interfaces. The computer procedure is used to predict field behavior of an instrumented pile subjected to cyclic loading. The predictions provide very good correlation with the field data. They also yield improved results compared to those from a HISS model with anisotropic hardening, partly because the DSC model allows for degradation or softening and interface response.

  20. 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.

  1. Experimental method to predict avalanches based on neural networks

    Directory of Open Access Journals (Sweden)

    V. V. Zhdanov

    2016-01-01

    Full Text Available The article presents results of experimental use of currently available statistical methods to classify the avalanche‑dangerous precipitations and snowfalls in the Kishi Almaty river basin. The avalanche service of Kazakhstan uses graphical methods for prediction of avalanches developed by I.V. Kondrashov and E.I. Kolesnikov. The main objective of this work was to develop a modern model that could be used directly at the avalanche stations. Classification of winter precipitations into dangerous snowfalls and non‑dangerous ones was performed by two following ways: the linear discriminant function (canonical analysis and artificial neural networks. Observational data on weather and avalanches in the gorge Kishi Almaty in the gorge Kishi Almaty were used as a training sample. Coefficients for the canonical variables were calculated by the software «Statistica» (Russian version 6.0, and then the necessary formula had been constructed. The accuracy of the above classification was 96%. Simulator by the authors L.N. Yasnitsky and F.М. Cherepanov was used to learn the neural networks. The trained neural network demonstrated 98% accuracy of the classification. Prepared statistical models are recommended to be tested at the snow‑avalanche stations. Results of the tests will be used for estimation of the model quality and its readiness for the operational work. In future, we plan to apply these models for classification of the avalanche danger by the five‑point international scale.

  2. Theoretical and experimental investigation of multispectral photoacoustic osteoporosis detection method

    Science.gov (United States)

    Steinberg, Idan; Hershkovich, Hadas Sara; Gannot, Israel; Eyal, Avishay

    2014-03-01

    Osteoporosis is a widespread disorder, which has a catastrophic impact on patients lives and overwhelming related to healthcare costs. Recently, we proposed a multispectral photoacoustic technique for early detection of osteoporosis. Such technique has great advantages over pure ultrasonic or optical methods as it allows the deduction of both bone functionality from the bone absorption spectrum and bone resistance to fracture from the characteristics of the ultrasound propagation. We demonstrated the propagation of multiple acoustic modes in animal bones in-vitro. To further investigate the effects of multiple wavelength excitations and of induced osteoporosis on the PA signal a multispectral photoacoustic system is presented. The experimental investigation is based on measuring the interference of multiple acoustic modes. The performance of the system is evaluated and a simple two mode theoretical model is fitted to the measured phase signals. The results show that such PA technique is accurate and repeatable. Then a multiple wavelength excitation is tested. It is shown that the PA response due to different excitation wavelengths revels that absorption by the different bone constitutes has a profound effect on the mode generation. The PA response is measured in single wavelength before and after induced osteoporosis. Results show that induced osteoporosis alters the measured amplitude and phase in a consistent manner which allows the detection of the onset of osteoporosis. These results suggest that a complete characterization of the bone over a region of both acoustic and optical frequencies might be used as a powerful tool for in-vivo bone evaluation.

  3. New experimental method for investigation of the nucleon polarizabilities

    International Nuclear Information System (INIS)

    Yevetska, O.; Watzlawik, S.; Ahrens, J.; Alkhazov, G.D.; Chizhov, V.P.; Maev, E.M.; Neumann-Cosel, P. von; Orischin, E.M.; Petrov, G.E.; Porte, J.-M.; Richter, A.; Sarantsev, V.V.; Schrieder, G.; Smirenin, Yu.V.

    2010-01-01

    At the continuous wave (cw) Superconducting Darmstadt Electron Linear Accelerator S-DALINAC, a new method has been developed for the determination of the electric (α-bar) and magnetic (β-bar) polarizabilities of the proton and the deuteron. For that purpose the energy and angular dependence of the differential cross-section for elastic γp and γd scattering of bremsstrahlung photons in the energy range between 20 and 100 MeV is measured by detecting the recoiling proton (deuteron) in coincidence with the scattered bremsstrahlung photon. α-bar and β-bar are then found by means of a best fit to a theoretical description of the scattering cross-section with these quantities as open parameters. The experimental setup consists of a bremsstrahlung photon facility, two specially designed high pressure hydrogen (deuterium) ionization chambers which serve as targets and detectors of the recoil proton (deuteron), NaI gamma spectrometers and several additional detectors for beam diagnostics and normalization. The whole setup was tested using bremsstrahlung photon beams with endpoint energies of 60 and 79.3 MeV. The results of the test experiments show that future high-statistics measurements are feasible.

  4. A study on the development of photoelastic experimental hybrid method for colour isochromatics (I)

    International Nuclear Information System (INIS)

    Hawong, Jai Sug; Nam, Jeong Hwan; Kim, Kyo Hyoung; Kwon, O Sung; Kwon, Gun; Park, Sung Han

    2010-01-01

    Isochromatics obtained from photoelastic experiment shows the stress distributions of the full field of a structure under load. Therefore, stress distributions of the structure can be read at a glance through isochromatics. Many experimental data can be obtained from isochromatics which are then used in various photoelastic experimental hybrid methods for stress analysis. Monochromatic light has however, until now been used in the photoelastic experimental hybrid method to produce black and white isochromatics. The use of black and white isochromatics in photoelastic experimental hybrid method for black and white isochromatics requires high fringe orders in order to obtain sufficient experimental data for photoelastic hybrid techniques. Accordingly, this paper develops the photoelastic experimental hybrid method for color isochromatics in which a fringe order of 1 is enough to gather the experimental data of the photoelastic experimental hybrid method. The method was applied to validate stress concentration problems. Experimental results from this study indicated that the photoelastic experimental hybrid method for color isochromatics is more precise than the photoelastic experimental hybrid method for black and white isochromatics. The use of few fringe orders in photoelastic experimental hybrid method for color isochromatics can offer significant advantages in stress analysis of real components using reflective-type photoelastic experimental method

  5. An Experimental Comparison of Two Different Methods in Astronomy Teaching

    OpenAIRE

    TÜRK, Cumhur; KALKAN, Hüseyin

    2017-01-01

    In this study, the efficiency of teaching with virtual reality programs (VRT) and teaching with physicalmodels (PMT), which are widely used in astronomy teaching, have been compared experimentally.The study has a quasi-experimental design and it was conducted with 106pre-service science teachers studying in the educational faculty of OndokuzMayıs University. The groups were determined by using simple random samplingmethod. As data collection tool Astronomy Achievement Test (AAT) was used. Ino...

  6. Crystallization of Polymers Investigated by Temperature-Modulated DSC

    OpenAIRE

    Maria Cristina Righetti

    2017-01-01

    The aim of this review is to summarize studies conducted by temperature-modulated differential scanning calorimetry (TMDSC) on polymer crystallization. This technique can provide several advantages for the analysis of polymers with respect to conventional differential scanning calorimetry. Crystallizations conducted by TMDSC in different experimental conditions are analysed and discussed, in order to illustrate the type of information that can be deduced. Isothermal and non-isothermal crystal...

  7. FTIR, XRD and DSC studies of nanochitosan, cellulose acetate and polyethylene glycol blend ultrafiltration membranes.

    Science.gov (United States)

    Vinodhini, P Angelin; K, Sangeetha; Thandapani, Gomathi; P N, Sudha; Jayachandran, Venkatesan; Sukumaran, Anil

    2017-11-01

    In the present work, a series of novel nanochitosan/cellulose acetate/polyethylene glycol (NCS/CA/PEG) blend flat sheet membranes were fabricated in different ratios (1:1:1, 1:1:2, 2:1:1, 2:1:2, 1:2:1, 2:2:1) in a polar solvent of N,N'-dimethylformamide (DMF) using the most popular phase inversion method. Nanochitosan was prepared by the ionotropic gelation method and its average particle size has been analyzed using Dynamic Light Scattering (DLS) method. The effect of blending of the three polymers was investigated using FTIR and XRD studies. FTIR results confirmed the formation of well-blended membranes and the XRD analysis revealed enhanced amorphous nature of the membrane ratio 2:1:2. DSC study was conducted to find out the thermal behavior of the blend membranes and the results clearly indicated good thermal stability and single glass transition temperature (T g ) of all the prepared membranes. Asymmetric nature and rough surface morphology was confirmed using SEM analysis. From the results it was evident that the blending of the polymers with higher concentration of nanochitosan can alter the nature of the resulting membranes to a greater extent and thus amorphous membranes were obtained with good miscibility and compatibility. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Recent advances and potential applications of modulated differential scanning calorimetry (mDSC) in drug development.

    Science.gov (United States)

    Knopp, Matthias Manne; Löbmann, Korbinian; Elder, David P; Rades, Thomas; Holm, René

    2016-05-25

    Differential scanning calorimetry (DSC) is frequently the thermal analysis technique of choice within preformulation and formulation sciences because of its ability to provide detailed information about both the physical and energetic properties of a substance and/or formulation. However, conventional DSC has shortcomings with respect to weak transitions and overlapping events, which could be solved by the use of the more sophisticated modulated DSC (mDSC). mDSC has multiple potential applications within the pharmaceutical field and the present review provides an up-to-date overview of these applications. It is aimed to serve as a broad introduction to newcomers, and also as a valuable reference for those already practising in the field. Complex mDSC was introduced more than two decades ago and has been an important tool for the quantification of amorphous materials and development of freeze-dried formulations. However, as discussed in the present review, a number of other potential applications could also be relevant for the pharmaceutical scientist. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Autonomous Experimentation of Carbon Nanotube Using Response Surface Methods

    Science.gov (United States)

    2015-03-26

    minimizes variance (Myers et al., 2009:286). Orthogonality is a very useful property, because it eliminates multicollinearity in the regressor variables...Montgomery et al., 2012:118). Multicollinearity is a common problem in data that is not collected from an experimental design. Multicollinearity can

  10. Comparing methods to quantify experimental transmission of infectious agents

    NARCIS (Netherlands)

    Velthuis, A.G.J.; Jong, de M.C.M.; Bree, de J.

    2007-01-01

    Transmission of an infectious agent can be quantified from experimental data using the transient-state (TS) algorithm. The TS algorithm is based on the stochastic SIR model and provides a time-dependent probability distribution over the number of infected individuals during an epidemic, with no need

  11. Experimental methods of reactor physics; Methodes experimentales de physique des reacteurs a neutrons thermiques

    Energy Technology Data Exchange (ETDEWEB)

    Breton, D; Lafore, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    This paper is a synthesis of various experimental methods in use with the reactors of the Commissariat a l'Energie Atomique. The main techniques used are mentioned and the difficulties encountered and the accuracy obtained are particularly dwelt upon. The application of these various methods to reactors in order to obtain specific results is also indicated. This paper consists of five parts. I - General methods. Macroscopic and microscopic flux distribution (anisotropy effect), power distribution, etc... II - Kinetic measurements a) pulsed neutron technique: apparatus and accuracy; application to {lambda}t and to anti reactivity measurements; application to graphite, light water and beryllium oxide. b) oscillation techniques: equipment and accuracy; application to the measurements of effective cross sections and resonance integrals. c) fluctuations: apparatus and technique of measurement. III - Poison methods. Description of methods for introducing and extracting the poison, difficulties encountered with light and heavy water, measurement of temperature coefficients and anti-reactivity. IV - Spectra measurements. Choice and development of foils, problems of measurement, application to spectral measurements for thermalization studies, application to dosimetry. V - Experimental shielding measurements. The technique and apparatus recently developed in this field are presented. (authors) [French] Cette communication fait une synthese des differentes methodes experimentales mises en oeuvre sur les reacteurs du CEA. Elle presente les principales techniques utilisees et insiste plus particulierement sur les difficultes rencontrees et la precision obtenue; elle indique egalement l'application de ces differentes methodes sur les reacteurs, en vue de l'obtention des resultats determines. Elle comporte cinq parties: I - METHODES GENERALES: Distribution de flux macroscopique et microscopique (effet d'anisotropie), distribution de puissance, etc... II - MESURES CINETIQUES: a

  12. Infrared spectra, Raman laser, XRD, DSC/TGA and SEM ...

    Indian Academy of Sciences (India)

    Ga2O3, Se metal, SnO, Sb2O3, HgO and PbCO3 are formed upon the reaction of acetamide aqueous solutions with Ga(NO3)3, SeO2, SnCl2, SbCl3, HgCl2 and Pb(NO3)2, respectively, at 90°C. Different amorphous or crystalline phases can be obtained depending upon the experimental conditions (molar ratios, metal salts ...

  13. Experimental Comparison of Probabilistic Shaping Methods for Unrepeated Fiber Transmission

    DEFF Research Database (Denmark)

    Renner, Julian; Fehenberger, Tobias; Yankov, Metodi Plamenov

    2017-01-01

    This paper studies the impact of probabilistic shaping on effective signal-to-noise ratios (SNRs) and achievable information rates (AIRs) in a back-to-back configuration and in unrepeated nonlinear fiber transmissions. For back-to-back, various shaped quadrature amplitude modulation (QAM......) distributions are found to have the same implementation penalty as uniform input. By demonstrating in transmission experiments that shaped QAM input leads to lower effective SNR than uniform input at a fixed average launch power, we experimentally confirm that shaping enhances the fiber nonlinearities. However......, shaping is ultimately found to increase the AIR, which is the most relevant figure of merit as it is directly related to spectral efficiency. In a detailed study of these shaping gains for the nonlinear fiber channel, four strategies for optimizing QAM input distributions are evaluated and experimentally...

  14. Development and validation of an open source quantification tool for DSC-MRI studies.

    Science.gov (United States)

    Gordaliza, P M; Mateos-Pérez, J M; Montesinos, P; Guzmán-de-Villoria, J A; Desco, M; Vaquero, J J

    2015-03-01

    This work presents the development of an open source tool for the quantification of dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion studies. The development of this tool is motivated by the lack of open source tools implemented on open platforms to allow external developers to implement their own quantification methods easily and without the need of paying for a development license. This quantification tool was developed as a plugin for the ImageJ image analysis platform using the Java programming language. A modular approach was used in the implementation of the components, in such a way that the addition of new methods can be done without breaking any of the existing functionalities. For the validation process, images from seven patients with brain tumors were acquired and quantified with the presented tool and with a widely used clinical software package. The resulting perfusion parameters were then compared. Perfusion parameters and the corresponding parametric images were obtained. When no gamma-fitting is used, an excellent agreement with the tool used as a gold-standard was obtained (R(2)>0.8 and values are within 95% CI limits in Bland-Altman plots). An open source tool that performs quantification of perfusion studies using magnetic resonance imaging has been developed and validated using a clinical software package. It works as an ImageJ plugin and the source code has been published with an open source license. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Method for Determining Volumetric Efficiency and Its Experimental Validation

    OpenAIRE

    Ambrozik Andrzej; Kurczyński Dariusz; Łagowski Piotr

    2017-01-01

    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, ...

  16. Experimental Method For Studying Habitual Behavior In Food Consumption

    Directory of Open Access Journals (Sweden)

    Naziha Kasraoui

    2015-03-01

    Full Text Available Abstract To investigate the process of habit formation in everyday life a sample of 126 participants students chooses an eating and drinking for three periods weeks. They completed the self-report habit each period and we have recorded their choices. All participants provided sufficient data for analysis and collected experimental data were examined over the study periods 3 weeks. Experimental analysis was used to examine the persistence of habit formation process in the behavior of participants. The game is carried out with 126 students and repeated for three periods. Using experimental laboratory data approach and economic analysis elasticity results show that into the presence of labor income and for 126 students of whom approximately 70 showed that habit formation process is persist in their behaviors along the three periods. The rest 30 of them who dont present habit formation in their behavior for the three periods did not materially affect our conclusion about the assumption of habit formation process. Participants to the game persistently spend too much in early periods they learn rapidly from their own experience to consume the same choice of meals and drinks. Their spending is closely linked to optimal consumption non conditional on earlier spending and they choose the same basket of goods in the future horizon which shows that theres a habit formation in the behaviors of participants.

  17. Development of a certified reference material for calibration of DSC and DTA below room temperature: NMIJ CRM 5401-a, Cyclohexane for Thermal Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yoshitaka, E-mail: y-shimizu@aist.go.jp; Ohte, Yoko; Kato, Kenji

    2013-09-20

    Highlights: • We developed a new CRM for quality assurance of DSC and DTA below room temperature. • Certified values are temperatures and enthalpies of two phase transitions. • Certified values agree with literature values. • Certified values are determined by adiabatic calorimetry and traceable to the SI. • Purity of this CRM was confirmed more than 0.9999. - Abstract: For the quality assurance of performance of differential scanning calorimeters (DSC) and differential thermal analyzers (DTA) below room temperature, we have developed “NMIJ CRM 5401-a, Cyclohexane for Thermal Analysis” applicable to calibration of DSC and DTA in the low temperature. Adiabatic calorimetry was used to measure the temperatures and enthalpies of solid–solid phase transition and fusion as certified values, and to determine the purity in amount of substance fraction as information. The certified values are consistent with their corresponding literature values within expanded uncertainties and have traceability to the SI. Purity in amount of substance fraction was measured by fractional melting method based on freezing point depression method and was confirmed to be more than 0.9999. NMIJ CRM 5401-a was produced based on a quality system in compliance with ISO Guide 34: 2000. We demonstrate the usefulness of NMIJ CRM 5401-a in the calibration, quality control, and validation aspects of DSC and DTA.

  18. Crystallization of Polymers Investigated by Temperature-Modulated DSC

    Directory of Open Access Journals (Sweden)

    Maria Cristina Righetti

    2017-04-01

    Full Text Available The aim of this review is to summarize studies conducted by temperature-modulated differential scanning calorimetry (TMDSC on polymer crystallization. This technique can provide several advantages for the analysis of polymers with respect to conventional differential scanning calorimetry. Crystallizations conducted by TMDSC in different experimental conditions are analysed and discussed, in order to illustrate the type of information that can be deduced. Isothermal and non-isothermal crystallizations upon heating and cooling are examined separately, together with the relevant mathematical treatments that allow the evolution of the crystalline, mobile amorphous and rigid amorphous fractions to be determined. The phenomena of ‘reversing’ and ‘reversible‘ melting are explicated through the analysis of the thermal response of various semi-crystalline polymers to temperature modulation.

  19. Theoretical analysis and experimental study of spray degassing method

    International Nuclear Information System (INIS)

    Wu Ruizhi; Shu Da; Sun Baode; Wang Jun; Li Fei; Chen Haiyan; Lu YanLing

    2005-01-01

    A new hydrogen-removal method of aluminum melt, spray degassing, is presented. The thermodynamic and kinetic analysis of the method are discussed. A comparison between the thermodynamics and kinetics of the spray degassing method and rotary impellor degassing method is made. The thermodynamic analysis shows that the relationship between the final hydrogen content of the aluminum melt and the ratio of purge gas flow rate to melt flow rate is linear. The result of thermodynamic calculation shows that, in spray degassing, when the ratio of G/q is larger than 2.2 x 10 -6 , the final hydrogen content will be less than 0.1 ml/100 g Al. From the kinetic analysis, the degassing effect is affected by both the size of melt droplets and the time that melt droplets move from sprayer to the bottom of the treatment tank. In numerical calculation, the hydrogen in aluminum melt can be degassed to 0.05 ml/100 g Al from 0.2 ml/100 g Al in 0.02 s with the spray degassing method. Finally, the water-model experiments are presented with the spray degassing method and rotary impellor degassing method. Melt experiments are also presented. Both the water-model experiments and the melt experiments show that the degassing effect of the spray degassing method is better than that of the rotary impeller method

  20. Experimental methods for studying the diffusion of radioactive gases in solids. VII. Sorption method

    International Nuclear Information System (INIS)

    Bekman, I.N.

    1983-01-01

    The details of the use of a sorption method in the study of the diffusion of gasses and vapors labeled with radioactive tracers in solids have been considered. Three variants of diffusion systems, which permit the determination of the diffusion coefficient and the solubility constant of gases both from the increase in the amount of diffusate in the sample and from the decrease in its amount in the reservoir, have been tested. Different ways of conducting the experiment have been discussed. A universal method for taking into account the processes of the absorption and scattering of radiation in the material of the sample has been proposed. The experimental results were treated with the aid of a specially developed program package, which is realized on computers of the BESM-6 type. Various mathematical models of the diffusion of gases in solids have been analyzed. Solutions of the diffusion equations under the boundary conditions of the sorption method for the cases of diffusion with trapping, dissociative diffusion, and diffusion in a plate containing spherical inclusions have been obtained. The method has been tested in the example case of the diffusion of a radiative inert gas, viz., radon-22, in low-density polyethylene

  1. Nano-DTA and nano-DSC with cantilever-type calorimeter

    International Nuclear Information System (INIS)

    Nakabeppu, Osamu; Deno, Kohei

    2016-01-01

    Highlights: • Nanocalorimetry with original cantilever type calorimeters. • The calorimeters showed the enthalpy resolution of 200 nJ level. • Nano-DTA of a binary alloy captured a probabilistic peak after solidification. • Power compensation DSC of a microgram level sample was demonstrated. • The DSC and DTA behavior were explained with a lumped model. - Abstract: Differential thermal analysis (DTA) and differential scanning calorimetry (DSC) of the minute samples in the range of microgram to nanogram were studied using original cantilever-type calorimeters. The micro-fabricated calorimeter with a heater and thermal sensors was able to perform a fast temperature scan at above 1000 K/s and a high-resolution heat measurement. The DTA of minuscule metal samples demonstrated some advances such as the thermal analysis of a 20 ng level indium and observation of a strange phase transition of a binary alloy. The power compensation type DSC using a thermal feedback system was also performed. Thermal information of a microgram level sample was observed as splitting into the DSC and DTA signals because of a mismatch between the sample and the calorimeter. Although there remains some room for improvement in terms of the heat flow detection, the behavior of the compensation system in the DSC was theoretically understood through a lumped model. Those experiments also produced some findings, such as a fin effect with sample loading, a measurable weight range, a calibration of the calorimeter and a product design concept. The development of the nano-DTA and nano-DSC will enable breakthroughs for the fast calorimetry of the microscopic size samples.

  2. Natural experimentation is a challenging method for identifying headache triggers.

    Science.gov (United States)

    Houle, Timothy T; Turner, Dana P

    2013-04-01

    In this study, we set out to determine whether individual headache sufferers can learn about the potency of their headache triggers (causes) using only natural experimentation. Headache patients naturally use the covariation of the presence-absence of triggers with headache attacks to assess the potency of triggers. The validity of this natural experimentation has never been investigated. A companion study has proposed 3 assumptions that are important for assigning causal status to triggers. This manuscript examines one of these assumptions, constancy in trigger presentation, using real-world conditions. The similarity of day-to-day weather conditions over 4 years, as well as the similarity of ovarian hormones and perceived stress over a median of 89 days in 9 regularly cycling headache sufferers, was examined using several available time series. An arbitrary threshold of 90% similarity using Gower's index identified similar days for comparison. The day-to-day variability in just these 3 headache triggers is substantial enough that finding 2 naturally similar days for which to contrast the effect of a fourth trigger (eg, drinking wine vs not drinking wine) will only infrequently occur. Fluctuations in weather patterns resulted in a median of 2.3 days each year that were similar (range 0-27.4). Considering fluctuations in stress patterns and ovarian hormones, only 1.5 days/month (95% confidence interval 1.2-2.9) and 2.0 days/month (95% confidence interval 1.9-2.2), respectively, met our threshold for similarity. Although assessing the personal causes of headache is an age-old endeavor, the great many candidate triggers exhibit variability that may prevent sound conclusions without assistance from formal experimentation or statistical balancing. © 2013 American Headache Society.

  3. Introduction to experimental infrared spectroscopy fundamentals and practical methods

    CERN Document Server

    Tasumi, Mitsuo; Ochiai, Shukichi

    2014-01-01

    Infrared spectroscopy is generally understood to mean the science of spectra relating to infrared radiation, namely electromagnetic waves, in the wavelength region occurring intermediately between visible light and microwaves. Measurements of infrared spectra have been providing useful information, for a variety of scientific research and industrial studies, for over half a century; this is set to continue in the foreseeable future. Introduction to Experimental Infrared Spectroscopy is intended to be a handy guide for those who have no, or limited, experience in infrared spectroscopi

  4. The experimental method for neutron dose-equivalent detection

    International Nuclear Information System (INIS)

    Ji Changsong

    1992-01-01

    A new method, for getting neutron dose-equivalent Cd rode absorption method is described. The method adopts Cd-rode-swarm buck absorption, which greatly improved the neutron sensitivity and simplified the adjustment method. By this method, the author has developed BH3105 model neutron dose equivalent meter, the sensitivity of this instrument reach 10 cps/μSvh -1 . γ-ray depression rate reaches 4000:1, the measurement range is 0.1 μSv/h-10 6 μSv/h. The energy response is good (from thermal neutron-14 MeV neutron), this instrument can be used to measure the dose equivalent of the neutron areas

  5. DSC study of martensite transformation in TiPt alloys

    CSIR Research Space (South Africa)

    Chikosha, S

    2012-09-01

    Full Text Available Conclusions drawn from this presentation were that when SPS, HP and Press and Sinter methods were used to form TiPt phase from elemental Ti and Pt powders, Press and Sinter was less successful. Presence of Ti-rich and Pt-rich phases coexisting...

  6. Melting and thermal history of poly(hydroxybutyrate-co-hydroxyvalerate) using step-scan DSC

    International Nuclear Information System (INIS)

    Gunaratne, L.M.W.K.; Shanks, R.A.

    2005-01-01

    Melting behaviour and crystal morphology of poly(3-hydroxybutyrate) (PHB) and its copolymer of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with various hydroxyvalerate (HV) contents [5 wt.% (PHB5HV), 8 wt.% (PHB8HV) and 12 wt.% (PHB12HV)] have been investigated by conventional DSC, step-scan differential scanning calorimetry (SDSC) and hot-stage polarised optical microscopy (HSPOM). Crystallisation behaviour of PHB and its copolymers were investigated by SDSC. Thermal properties were investigated after different crystallisation treatments, fast, medium and slow cooling. Multiple melting peak behaviour was observed for all polymers. SDSC data revealed that PHB and its copolymers undergo melting-recrystallisation-remelting during heating, as evidenced by exothermic peaks in the IsoK baseline (non-reversing signal). An increase in degree of crystallinity due to significant melt-recrystallisation was observed for slow-cooled copolymers. PHB5HV showed different crystal morphologies for various crystallisation conditions. SDSC proved a convenient and precise method for measurement of the apparent thermodynamic specific heat (reversing signal) HSPOM results showed that the crystallisation rates and sizes of spherulites were significantly reduced as crystallisation rate increased

  7. Two DSC Glass Transitions in Miscible Blends of Polyisoprene / Poly(4-tert-butyl styrene)

    Science.gov (United States)

    Zhao, Junshu; Sun, Ye; Yu, Lian; Ediger, Mark

    2009-03-01

    Conventional and temperature modulated differential scanning calorimetry experiments have been carried out on miscible blends of polyisoprene (PI) and poly(4-tert-butyl styrene) (P4tBS) over a broad composition range. This system is characterized by an extraordinarily large component Tg difference (˜215 K) between the two homopolymers. Two distinct calorimetric Tgs were observed in blends with an intermediate composition range (25%˜50% PI) by both conventional and temperature modulated DSC. Good agreement was found between the Tg values measured by the two methods. Fitting of the measured Tgs to the Lodge-McLeish model gives a φself of 0.62˜0.64 for PI in this blend and 0.02˜0.05 for P4tBS. The extracted φself for PIis comparable to reported values for PEO in blends with PMMA and is significantly larger than those reported for other PI blends with smaller component Tg differences. This observation suggests the presence of a confinement effect in PI/P4tBS blends, which results in enhanced fast component dynamics below the effective Tg of the slow component.

  8. Comparative study by TG and DSC Of membranes polyamide66/bentonite clay nanocomposite; Estudo comparativo por TG e DSC de membranas de nanocompositos poliamida66/argila bentonitica

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, K.M. de; Kojuch, L R; Araujo, E M; Lira, H.L., E-mail: keilamm@ig.com.b [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais; Lima, F [Universidade Estadual da Paraiba (UEPB), Campina Grande, PB (Brazil). Dept. de Quimica

    2010-07-01

    In this study, it was obtained membranes of nanocomposites polyamide66 with 3 and 5% bentonite clay consists of silicates in layers from the interior of Paraiba. The clay was treated with a quaternary ammonium salt in order to make it organophilic. The membranes were prepared by phase inversion technique from the nanocomposites in solution. The clays were characterized by X-ray diffraction (XRD) and thermogravimetry (TG). Also the membranes were characterized by differential scanning calorimetry (DSC) and TG. The XRD and TG confirmed the presence of salt in the clay and thermal stability of the treated clay. For DSC, it was observed that there was no change in melting temperature of the membranes of nanocomposites compared to membrane pure polyamide66. By TG, it was found that the decomposition of the membranes of polyamide66 with treated clay were higher compared with the untreated clay. (author)

  9. Practical application of stereological methods in experimental kidney animal models.

    Science.gov (United States)

    Fernández García, María Teresa; Núñez Martínez, Paula; García de la Fuente, Vanessa; Sánchez Pitiot, Marta; Muñiz Salgueiro, María Del Carmen; Perillán Méndez, Carmen; Argüelles Luis, Juan; Astudillo González, Aurora

    The kidneys are vital organs responsible for excretion, fluid and electrolyte balance and hormone production. The nephrons are the kidney's functional and structural units. The number, size and distribution of the nephron components contain relevant information on renal function. Stereology is a branch of morphometry that applies mathematical principles to obtain three-dimensional information from serial, parallel and equidistant two-dimensional microscopic sections. Because of the complexity of stereological studies and the lack of scientific literature on the subject, the aim of this paper is to clearly explain, through animal models, the basic concepts of stereology and how to calculate the main kidney stereological parameters that can be applied in future experimental studies. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  10. Photoelectrochemical water splitting standards, experimental methods, and protocols

    CERN Document Server

    Chen, Zhebo; Miller, Eric

    2014-01-01

    This book outlines many of the techniques involved in materials development and characterization for photoelectrochemical (PEC) - for example, proper metrics for describing material performance, how to assemble testing cells and prepare materials for assessment of their properties, and how to perform the experimental measurements needed to achieve reliable results towards better scientific understanding. For each technique, proper procedure, benefits, limitations, and data interpretation are discussed. Consolidating this information in a short, accessible, and easy to read reference guide will allow researchers to more rapidly immerse themselves into PEC research and also better compare their results against those of other researchers to better advance materials development. This book serves as a "how-to" guide for researchers engaged in or interested in engaging in the field of photoelectrochemical (PEC) water splitting. PEC water splitting is a rapidly growing field of research in which the goal is to deve...

  11. Fast-Scan DSC and its role in pharmaceutical physical form characterisation and selection.

    Science.gov (United States)

    Ford, James L; Mann, Timothy E

    2012-04-01

    Conventional rate Differential Scanning Calorimetry (DSC) has been used for many years as a tool in the analysis of pharmaceutical materials. In recent years an extension of the technique to include fast heating and cooling rates has become more prevalent. Broadly termed Fast-Scan DSC, this review examines the current applications of this technique to the characterisation and selection of pharmaceutical materials. Its increasing use encompasses the characterisation of amorphousness in crystalline materials, the characterisation of polymorphs and polymorphic transitions, the solubility of drugs in polymers, and characterisation of dosage forms. Notwithstanding the advantages of analytical speed in analytical turnover, the review emphasises the advantages of Fast-Scan DSC in its sensitivity which allows the separation of overlapping thermal events, the reduction it provides in degradation during the scanning process and its role in determining solubility in waxy and polymeric based systems. A comparison of the uses of Fast-Scan DSC to modulated DSC techniques and localised thermal analysis is also given. © 2011 Elsevier B.V. All rights reserved.

  12. DSC: software tool for simulation-based design of control strategies applied to wastewater treatment plants.

    Science.gov (United States)

    Ruano, M V; Ribes, J; Seco, A; Ferrer, J

    2011-01-01

    This paper presents a computer tool called DSC (Simulation based Controllers Design) that enables an easy design of control systems and strategies applied to wastewater treatment plants. Although the control systems are developed and evaluated by simulation, this tool aims to facilitate the direct implementation of the designed control system to the PC of the full-scale WWTP (wastewater treatment plants). The designed control system can be programmed in a dedicated control application and can be connected to either the simulation software or the SCADA of the plant. To this end, the developed DSC incorporates an OPC server (OLE for process control) which facilitates an open-standard communication protocol for different industrial process applications. The potential capabilities of the DSC tool are illustrated through the example of a full-scale application. An aeration control system applied to a nutrient removing WWTP was designed, tuned and evaluated with the DSC tool before its implementation in the full scale plant. The control parameters obtained by simulation were suitable for the full scale plant with only few modifications to improve the control performance. With the DSC tool, the control systems performance can be easily evaluated by simulation. Once developed and tuned by simulation, the control systems can be directly applied to the full-scale WWTP.

  13. D-DSC: Decoding Delay-based Distributed Source Coding for Internet of Sensing Things.

    Science.gov (United States)

    Aktas, Metin; Kuscu, Murat; Dinc, Ergin; Akan, Ozgur B

    2018-01-01

    Spatial correlation between densely deployed sensor nodes in a wireless sensor network (WSN) can be exploited to reduce the power consumption through a proper source coding mechanism such as distributed source coding (DSC). In this paper, we propose the Decoding Delay-based Distributed Source Coding (D-DSC) to improve the energy efficiency of the classical DSC by employing the decoding delay concept which enables the use of the maximum correlated portion of sensor samples during the event estimation. In D-DSC, network is partitioned into clusters, where the clusterheads communicate their uncompressed samples carrying the side information, and the cluster members send their compressed samples. Sink performs joint decoding of the compressed and uncompressed samples and then reconstructs the event signal using the decoded sensor readings. Based on the observed degree of the correlation among sensor samples, the sink dynamically updates and broadcasts the varying compression rates back to the sensor nodes. Simulation results for the performance evaluation reveal that D-DSC can achieve reliable and energy-efficient event communication and estimation for practical signal detection/estimation applications having massive number of sensors towards the realization of Internet of Sensing Things (IoST).

  14. Experimental study for development of thermic lance cutting method

    International Nuclear Information System (INIS)

    Machida, N.; Katano, Y.; Kamiya, Y.

    1988-01-01

    A series of experiments on a thermic lance cutting method were carried out to obtain useful data for the practical application of this method to the dismantling of reinforced concrete. As a first step, a performance experiment was executed to study basic cutting performance relating to oxygen consumption, extent of bar loss and cutting speed, as well as by-products generated during cutting work such as powdered dust, gas, fumes and slag. An automated and remote-controlled cutting machine was then developed utilizing automated bar supply and ignition. This paper describes the result of these experiments. (author)

  15. Magnetic characterisation of recording materials: design, instrumentation and experimental methods

    NARCIS (Netherlands)

    Samwel, E.O.

    1995-01-01

    The progress being made in the field of magnetic recording is extremely fast. The need to keep this progress going, leads to new types of recording materials which require advanced measurement systems and measurement procedures. Furthermore, the existing measurement methods need to be reviewed as

  16. An entrepreneurial physics method and its experimental test

    Science.gov (United States)

    Brown, Robert

    2012-02-01

    As faculty in a master's program for entrepreneurial physics and in an applied physics PhD program, I have advised upwards of 40 master and doctoral theses in industrial physics. I have been closely involved with four robust start-up manufacturing companies focused on physics high-technology and I have spent 30 years collaborating with industrial physicists on research and development. Thus I am in a position to reflect on many articles and advice columns centered on entrepreneurship. What about the goals, strategies, resources, skills, and the 10,000 hours needed to be an entrepreneur? What about business plans, partners, financing, patents, networking, salesmanship and regulatory affairs? What about learning new technology, how to solve problems and, in fact, learning innovation itself? At this point, I have my own method to propose to physicists in academia for incorporating entrepreneurship into their research lives. With this method, we do not start with a major invention or discovery, or even with a search for one. The method is based on the training we have, and the teaching we do (even quantum electrodynamics!), as physicists. It is based on the networking we build by 1) providing courses of continuing education for people working in industry and 2) through our undergraduate as well as graduate students who have gone on to work in industry. In fact, if we were to be limited to two words to describe the method, they are ``former students.'' Data from local and international medical imaging manufacturing industry are presented.

  17. Interleaved Carbon Minibeams: An Experimental Radiosurgery Method With Clinical Potential

    Energy Technology Data Exchange (ETDEWEB)

    Dilmanian, F. Avraham, E-mail: dilmanian@bnl.gov [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Department of Radiation Oncology, Stony Brook University Medical Center, NY (United States); Department of Neurology, Stony Brook University Medical Center, NY (United States); Rusek, Adam [NASA Space Radiation Laboratory, Brookhaven National Laboratory, Upton, NY (United States); Fois, Giovanna R. [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Physics Department, University of Cagliari, Sardinia (Italy); Olschowka, John [Department of Neurobiology and Anatomy, University of Rochester, Rochester, NY (United States); Desnoyers, Nicolle R. [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Ross University School of Veterinary Medicine, Basseterre, St. Kitts, West Indies (Country Unknown); Park, Jane Y. [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Dioszegi, Istvan [Nonproliferation and National Security Department, Brookhaven National Laboratory, Upton, NY (United States); Dane, Bari; Wang Ruiliang [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Tomasi, Dardo [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); National Institute on Alcoholism and Alcohol Abuse, Bethesda, MD (United States); Lee, Hedok [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Hurley, Sean D. [Department of Neurobiology and Anatomy, University of Rochester, Rochester, NY (United States); Coyle, Patricia K. [Department of Neurology, Stony Brook University Medical Center, NY (United States); Meek, Allen G. [Department of Radiation Oncology, Stony Brook University Medical Center, NY (United States); O' Banion, M. Kerry [Department of Neurobiology and Anatomy, University of Rochester, Rochester, NY (United States)

    2012-10-01

    Purpose: To evaluate the efficacy of 'interleaved carbon minibeams' for ablating a 6.5-mm target in a rabbit brain with little damage to the surrounding brain. The method is based on the well-established tissue-sparing effect of arrays of thin planes of radiation. Methods and Materials: Broad carbon beams from the National Aeronautics and Space Agency Space Radiation Facility at Brookhaven National Laboratory were segmented into arrays of parallel, horizontal, 0.3-mm-thick planar beams (minibeams). The minibeams' gradual broadening in tissues resulted in 0.525-mm beam thickness at the target's proximal side in the spread-out Bragg peak. Interleaving was therefore implemented by choosing a 1.05 mm beam spacing on-center. The anesthetized rabbit, positioned vertically on a stage capable of rotating about a vertical axis, was exposed to arrays from four 90 Degree-Sign angles, with the stage moving up by 0.525 mm in between. This produced a solid radiation field at the target while exposing the nontargeted tissues to single minibeam arrays. The target 'physical' absorbed dose was 40.2 Gy. Results: The rabbit behaved normally during the 6-month observation period. Contrast magnetic resonance imaging and hematoxylin and eosin histology at 6 months showed substantial focal target damage with little damage to the surrounding brain. Conclusion: We plan to evaluate the method's therapeutic efficacy by comparing it with broad-beam carbon therapy in animal models. The method's merits would combine those of carbon therapy (i.e., tight target dose because of the carbon's Bragg-peak, sharp dose falloff, and high relative biological effectiveness at the target), together with the method's low impact on the nontargeted tissues. The method's smaller impact on the nontargeted brain might allow carbon therapy at higher target doses and/or lower normal tissue impact, thus leading to a more effective treatment of radioresistant

  18. Experimental method for calculation of effective doses in interventional radiology; Metodo experimental para calculo de dosis efectivas en radiologia intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Herraiz Lblanca, M. D.; Diaz Romero, F.; Casares Magaz, O.; Garrido Breton, C.; Catalan Acosta, A.; Hernandez Armas, J.

    2013-07-01

    This paper proposes a method that allows you to calculate the effective dose in any interventional radiology procedure using an anthropomorphic mannequin Alderson RANDO and dosimeters TLD 100 chip. This method has been applied to an angio Radiology procedure: the biliary drainage. The objectives that have been proposed are: to) put together a method that, on an experimental basis, allows to know dosis en organs to calculate effective dose in complex procedures and b) apply the method to the calculation of the effective dose of biliary drainage. (Author)

  19. Experimental continuously reinforced concrete pavement parameterization using nondestructive methods

    Directory of Open Access Journals (Sweden)

    L. S. Salles

    Full Text Available ABSTRACT Four continuously reinforced concrete pavement (CRCP sections were built at the University of São Paulo campus in order to analyze the pavement performance in a tropical environment. The sections short length coupled with particular project aspects made the experimental CRCP cracking be different from the traditional CRCP one. After three years of construction, a series of nondestructive testing were performed - Falling Weight Deflectometer (FWD loadings - to verify and to parameterize the pavement structural condition based on two main properties: the elasticity modulus of concrete (E and the modulus of subgrade reaction (k. These properties estimation was obtained through the matching process between real and EverFE simulated basins with the load at the slab center, between two consecutive cracks. The backcalculation results show that the lack of anchorage at the sections end decreases the E and k values and that the longitudinal reinforcement percentage provides additional stiffness to the pavement. Additionally, FWD loadings tangential to the cracks allowed the load transfer efficiency (LTE estimation determination across cracks. The LTE resulted in values above 90 % for all cracks.

  20. ADVANTAGES AND THERMODYNAMIC LIMITATIONS OF THE EXPERIMENTAL SORPTION ISOSTERIC METHOD

    Directory of Open Access Journals (Sweden)

    FARID B. CORTÉS

    2013-01-01

    Full Text Available Una revisión de las ventajas y las limitaciones termodinámicas presentes en el método experimental sorción isostérica (SIM muestra que el SIM no garantiza una cantidad adsorbida constante. Las isósteras calculadas que consideran comportamiento de gas ideal muestran que en el SIM la masa de gas en el volumen muerto del sistema al incrementar la presión de equilibrio debido a los materiales desorbidos. El SIM es útil y efectivo para obtener datos termodinámicos de alta precisión para la sorción de gases en materiales micro y nanoporosos a bajas presiones y temperaturas. Por el contrario, cuando la presión y la temperatura son altas la desorción no es despreciable, por lo tanto el SIM no es aplicable. Los errores en los cálculos del calor isostérico usando SIM pueden ser reducidos usando procedimientos experimentales tradicionales como las isobaras e isotermas de adsorción para generar las isósteras a altas presiones y temperaturas. Como alternativa, correcciones por presión y temperatura, o un experimento que, después de cada incremento de temperatura permita a la dosis de gas compensar la masa desorbida, garantizaría una cantidad adsorbida constante y, por consiguiente, un comportamiento isostérico mediante medidas directas.

  1. Using Experimental Methods to Investigate Discriminatory Tendencies: A Lesson Report

    Directory of Open Access Journals (Sweden)

    Yu-Wen Chen

    2013-08-01

    Full Text Available Using dictator games in experimental analysis, this lesson report demonstrates the process and results of a postgraduate class project in which university students were instructed to scientifically investigate and explore one of German society’s most hotly-contested issues: the level of discriminatory tendencies of non-Muslims towards Muslims. The results of this class project show little or no discriminatory tendencies toward Muslims. Instead, the university students under our investigation tended to act favorably, or at the very least, fairly toward Muslims. We expect that this lesson report can demonstrate how a postgraduate course can be conducted in an innovative way, empowering students to collect primary data and finishing a small scientific project during the span of a semester. Dieser Bericht stellt die Prozesse und Ergebnisse einer experimentellen Studie eines Postgraduierten-Kurses der Universität Greifswald dar. Wir zeigen, wie Studierende das Thema Migration innovativ untersuchen können, indem sie neben theoretischen Lerninhalten an experimentelle Methoden sowie die Primärforschung herangeführt werden. Anhand eines Diktatorspiels wurden die teilnehmenden Studenten angeleitet, ein in der Öffentlichkeit kontrovers debattiertes Thema wissenschaftlich zu untersuchen: Diskriminierende Tendenzen von Nicht-Muslimen gegenüber Muslimen. Die Ergebnisse dieser Studie lassen jedoch nicht auf diskriminierende Tendenzen der Studenten schließen. Stattdessen deuten sie darauf hin, dass sich die Studierenden zumindest fair gegenüber Muslimen verhalten.

  2. Experimental methods for laboratory-scale ensilage of lignocellulosic biomass

    International Nuclear Information System (INIS)

    Tanjore, Deepti; Richard, Tom L.; Marshall, Megan N.

    2012-01-01

    Anaerobic fermentation is a potential storage method for lignocellulosic biomass in biofuel production processes. Since biomass is seasonally harvested, stocks are often dried or frozen at laboratory scale prior to fermentation experiments. Such treatments prior to fermentation studies cause irreversible changes in the plant cells, influencing the initial state of biomass and thereby the progression of the fermentation processes itself. This study investigated the effects of drying, refrigeration, and freezing relative to freshly harvested corn stover in lab-scale ensilage studies. Particle sizes, as well as post-ensilage drying temperatures for compositional analysis, were tested to identify the appropriate sample processing methods. After 21 days of ensilage the lowest pH value (3.73 ± 0.03), lowest dry matter loss (4.28 ± 0.26 g. 100 g-1DM), and highest water soluble carbohydrate (WSC) concentrations (7.73 ± 0.26 g. 100 g-1DM) were observed in control biomass (stover ensiled within 12 h of harvest without any treatments). WSC concentration was significantly reduced in samples refrigerated for 7 days prior to ensilage (3.86 ± 0.49 g. 100 g −1 DM). However, biomass frozen prior to ensilage produced statistically similar results to the fresh biomass control, especially in treatments with cell wall degrading enzymes. Grinding to decrease particle size reduced the variance amongst replicates for pH values of individual reactors to a minor extent. Drying biomass prior to extraction of WSCs resulted in degradation of the carbohydrates and a reduced estimate of their concentrations. The methods developed in this study can be used to improve ensilage experiments and thereby help in developing ensilage as a storage method for biofuel production. -- Highlights: ► Laboratory-scale methods to assess the influence of ensilage biofuel production. ► Drying, freezing, and refrigeration of biomass influenced microbial fermentation. ► Freshly ensiled stover exhibited

  3. Experimental study on enriching 12C by centrifuge method

    International Nuclear Information System (INIS)

    Xiao Huaxian

    1994-07-01

    The diamond made from the highly enriched 12 C, whose thermal conductivity and electric insulativity are much better than that of natural diamond, has widely uses in new and high technology. In many enriching 12 C methods, the gas centrifuge method is superior to others. After selecting the appropriate process gas and solving key problems, such as feed and extract, the separation experiments are performed by a single stage of centrifuge. To increase the separation capacity of single machine, various parameters in the centrifugal separation are optimized, and appropriate mechanical drive, thermal drive, hold-up and process parameters are selected. The optimal operating condition of single machine is also obtained in the cascade. Thus, highly enriched 12 C is produced in the centrifuge cascade

  4. Experimental evaluation of mechanical properties of softwood using acoustic methods

    Czech Academy of Sciences Publication Activity Database

    Tippner, J.; Hrivnák, J.; Kloiber, Michal

    2016-01-01

    Roč. 11, č. 1 (2016), s. 503-518 ISSN 1930-2126 R&D Projects: GA MK(CZ) DF11P01OVV001 Keywords : non destructive testing * Norway spruce * Scots pine * Silver fir * sound speed * strength * stress wave Subject RIV: AL - Art, Architecture, Cultural Heritage Impact factor: 1.321, year: 2016 http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_1_503_Tippner_Mechanical_Properties_Acoustic_Methods/4018

  5. Experimental Methods for Implementing Graphene Contacts to Finite Bandgap Semiconductors

    DEFF Research Database (Denmark)

    Meyer-Holdt, Jakob

    Present Ph.D. thesis describes my work on implanting graphene as electrical contact to finite bandgap semiconductors. Different transistor architectures, types of graphene and finite bandgap semiconductors have been employed. The device planned from the beginning of my Ph.D. fellowship...... contacts to semiconductor nanowires, more specifically, epitaxially grown InAs nanowires. First, we tried a top down method where CVD graphene was deposited on substrate supported InAs nanowires followed by selective graphene ashing to define graphene electrodes. While electrical contact between...

  6. The development of the code package PERMAK--3D//SC--1

    International Nuclear Information System (INIS)

    Bolobov, P. A.; Oleksuk, D. A.

    2011-01-01

    Code package PERMAK-3D//SC-1 was developed for performing pin-by-pin coupled neutronic and thermal hydraulic calculation of the core fragment of seven fuel assemblies and was designed on the basis of 3D multigroup pin-by-pin code PERMAK-3D and 3D (subchannel) thermal hydraulic code SC-1 The code package predicts axial and radial pin-by-pin power distribution and coolant parameters in stimulated region (enthalpies,, velocities,, void fractions,, boiling and DNBR margins).. The report describes some new steps in code package development. Some PERMAK-3D//SC-1 outcomes of WWER calculations are presented in the report. (Authors)

  7. A discussion of the principles and applications of Modulated Temperature DSC (MTDSC).

    Science.gov (United States)

    Verdonck, E; Schaap, K; Thomas, L C

    1999-12-01

    The benefits of Modulated Temperature DSC (MTDSC) over conventional differential scanning calorimetry (DSC) for studying thermal transitions in materials are reviewed by means of examples. These include the separation of overlapping phenomena such as melting/recrystallization in semi-crystalline materials, the heat capacity variation and enthalpic relaxation at the glass transition, and transitions from the different components of a blend. In addition, examples are presented demonstrating the ability of MTDSC to detect subtle transitions more readily and without loss of resolution. The possibility of measuring heat capacity in quasi-isothermal conditions and the evaluation of the thermal conductivity of a material are explained.

  8. Calorimetric sensitivity and thermal resolution of a novel miniaturized ceramic DSC chip in LTCC technology

    Energy Technology Data Exchange (ETDEWEB)

    Missal, Wjatscheslaw, E-mail: wmissal@gmx.net [Department of Functional Materials, University of Bayreuth, 95440 Bayreuth (Germany); Kita, Jaroslaw [Department of Functional Materials, University of Bayreuth, 95440 Bayreuth (Germany); Wappler, Eberhard [wsk Mess- und Datentechnik GmbH, Gueterbahnhofstr. 1, 63450 Hanau (Germany); Bechtold, Franz [VIA electronic GmbH, Robert-Friese-Str. 3, 07629 Hermsdorf (Germany); Moos, Ralf [Department of Functional Materials, University of Bayreuth, 95440 Bayreuth (Germany)

    2012-09-10

    Highlights: Black-Right-Pointing-Pointer Unique vertical design of a DSC device manufactured in the low-cost LTCC technology and therefore capable of one-way use. Black-Right-Pointing-Pointer Fully functional DSC device with a size of only 1.5 mm Multiplication-Sign 11 mm Multiplication-Sign 39 mm enabling very low power consumption. Black-Right-Pointing-Pointer Comparable measurement performance as conventional DSC whilst also suitable for mobile thermal analysis. Black-Right-Pointing-Pointer Thermal resolution is 0.12 (TAWN test). Repeatability of the peak area is within 0.3% for indium samples. Black-Right-Pointing-Pointer Calorimetric sensitivity: linear with regard to temperature and independent from sample mass and heating rate in wide ranges. - Abstract: The calorimetric properties of a novel miniaturized ceramic differential scanning calorimeter device (MC-DSC) with integrated heater and crucible are presented. All features of a conventional DSC apparatus (including oven) are integrated into this DSC device of the size 11 mm Multiplication-Sign 39 mm Multiplication-Sign 1.5 mm. The MC-DSC device is suitable for one-way use, since it is fully manufactured in the low-cost planar low temperature co-fired ceramics technology. First characterization of this device is performed using indium, tin and zinc samples. The calorimetric sensitivity at 156.6 Degree-Sign C is 0.24 J/ Degree-Sign C s. It depends linearly on temperature in the range of at least 150 Degree-Sign C and 420 Degree-Sign C. The calorimetric sensitivity is constant up to an enthalpy of fusion of at least {Delta}H = 750 mJ (at 156.6 Degree-Sign C). The thermal analysis of indium in direct contact to the crucible of the chip even reveals a constant calorimetric sensitivity up to an enthalpy of fusion of at least {Delta}H = 1000 mJ. The repeatability of the peak area is within {+-}0.3% (11 mg indium, 10 measurements). The thermal resolution determined using 4,4 Prime -azoxyanisole under TAWN test

  9. Experimental evaluation of optimization method for developing ultraviolet barrier coatings

    Science.gov (United States)

    Gonome, Hiroki; Okajima, Junnosuke; Komiya, Atsuki; Maruyama, Shigenao

    2014-01-01

    Ultraviolet (UV) barrier coatings can be used to protect many industrial products from UV attack. This study introduces a method of optimizing UV barrier coatings using pigment particles. The radiative properties of the pigment particles were evaluated theoretically, and the optimum particle size was decided from the absorption efficiency and the back-scattering efficiency. UV barrier coatings were prepared with zinc oxide (ZnO) and titanium dioxide (TiO2). The transmittance of the UV barrier coating was calculated theoretically. The radiative transfer in the UV barrier coating was modeled using the radiation element method by ray emission model (REM2). In order to validate the calculated results, the transmittances of these coatings were measured by a spectrophotometer. A UV barrier coating with a low UV transmittance and high VIS transmittance could be achieved. The calculated transmittance showed a similar spectral tendency with the measured one. The use of appropriate particles with optimum size, coating thickness and volume fraction will result in effective UV barrier coatings. UV barrier coatings can be achieved by the application of optical engineering.

  10. Prediction of skin sensitizers using alternative methods to animal experimentation.

    Science.gov (United States)

    Johansson, Henrik; Lindstedt, Malin

    2014-07-01

    Regulatory frameworks within the European Union demand that chemical substances are investigated for their ability to induce sensitization, an adverse health effect caused by the human immune system in response to chemical exposure. A recent ban on the use of animal tests within the cosmetics industry has led to an urgent need for alternative animal-free test methods that can be used for assessment of chemical sensitizers. To date, no such alternative assay has yet completed formal validation. However, a number of assays are in development and the understanding of the biological mechanisms of chemical sensitization has greatly increased during the last decade. In this MiniReview, we aim to summarize and give our view on the recent progress of method development for alternative assessment of chemical sensitizers. We propose that integrated testing strategies should comprise complementary assays, providing measurements of a wide range of mechanistic events, to perform well-educated risk assessments based on weight of evidence. © 2014 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  11. Interleaved Carbon Minibeams: An Experimental Radiosurgery Method With Clinical Potential

    International Nuclear Information System (INIS)

    Dilmanian, F. Avraham; Rusek, Adam; Fois, Giovanna R.; Olschowka, John; Desnoyers, Nicolle R.; Park, Jane Y.; Dioszegi, Istvan; Dane, Bari; Wang Ruiliang; Tomasi, Dardo; Lee, Hedok; Hurley, Sean D.; Coyle, Patricia K.; Meek, Allen G.; O’Banion, M. Kerry

    2012-01-01

    Purpose: To evaluate the efficacy of “interleaved carbon minibeams” for ablating a 6.5-mm target in a rabbit brain with little damage to the surrounding brain. The method is based on the well-established tissue-sparing effect of arrays of thin planes of radiation. Methods and Materials: Broad carbon beams from the National Aeronautics and Space Agency Space Radiation Facility at Brookhaven National Laboratory were segmented into arrays of parallel, horizontal, 0.3-mm-thick planar beams (minibeams). The minibeams’ gradual broadening in tissues resulted in 0.525-mm beam thickness at the target’s proximal side in the spread-out Bragg peak. Interleaving was therefore implemented by choosing a 1.05 mm beam spacing on-center. The anesthetized rabbit, positioned vertically on a stage capable of rotating about a vertical axis, was exposed to arrays from four 90° angles, with the stage moving up by 0.525 mm in between. This produced a solid radiation field at the target while exposing the nontargeted tissues to single minibeam arrays. The target “physical” absorbed dose was 40.2 Gy. Results: The rabbit behaved normally during the 6-month observation period. Contrast magnetic resonance imaging and hematoxylin and eosin histology at 6 months showed substantial focal target damage with little damage to the surrounding brain. Conclusion: We plan to evaluate the method’s therapeutic efficacy by comparing it with broad-beam carbon therapy in animal models. The method’s merits would combine those of carbon therapy (i.e., tight target dose because of the carbon’s Bragg-peak, sharp dose falloff, and high relative biological effectiveness at the target), together with the method’s low impact on the nontargeted tissues. The method’s smaller impact on the nontargeted brain might allow carbon therapy at higher target doses and/or lower normal tissue impact, thus leading to a more effective treatment of radioresistant tumors. It should also make the method more

  12. Experimental Validation for Hot Stamping Process by Using Taguchi Method

    Science.gov (United States)

    Fawzi Zamri, Mohd; Lim, Syh Kai; Razlan Yusoff, Ahmad

    2016-02-01

    Due to the demand for reduction in gas emissions, energy saving and producing safer vehicles has driven the development of Ultra High Strength Steel (UHSS) material. To strengthen UHSS material such as boron steel, it needed to undergo a process of hot stamping for heating at certain temperature and time. In this paper, Taguchi method is applied to determine the appropriate parameter of thickness, heating temperature and heating time to achieve optimum strength of boron steel. The experiment is conducted by using flat square shape of hot stamping tool with tensile dog bone as a blank product. Then, the value of tensile strength and hardness is measured as response. The results showed that the lower thickness, higher heating temperature and heating time give the higher strength and hardness for the final product. In conclusion, boron steel blank are able to achieve up to 1200 MPa tensile strength and 650 HV of hardness.

  13. Superconducting microstrip antennas: An experimental comparison of two feeding methods

    International Nuclear Information System (INIS)

    Richard, M.A.; Claspy, P.C.; Bhasin, K.B.

    1993-01-01

    The recent discovery of high-temperature superconductors (HTS's) has generated a substantial amount of interest in microstrip antenna applications. However, the high permittivity of substrates compatible with HTS causes difficulty in feeding such antennas because of the high patch edge impedance. In this paper, two methods for feeding HTS microstrip antennas at K and Ka-band are examined. Superconducting microstrip antennas that are directly coupled and gap-coupled to a microstrip transmission line have been designed and fabricated on lanthanum aluminate substrates using Y-Ba-Cu-O superconducting thin films. Measurements from these antennas, including input impedance, bandwidth, efficiency, and patterns, are presented and compared with published models. The measured results demonstrate that usable antennas can be constructed using either of these architectures, although the antennas suffer from narrow bandwidths. In each case, the HTS antenna shows a substantial improvement over an identical antenna made with normal metals

  14. Development of experimental methods for measuring fuel elements burnup

    International Nuclear Information System (INIS)

    PEREDA, C; HENRIQUEZ, C; NAVARRO, G; TORRES, H; KLEIN, J; CALDERON, D; MEDEL, J; MUTIS, O; DAIE, J; ITURRIETA, L; LONCOMILLA, M; ZAMBRANO, J; KESTELMAN, A

    2003-01-01

    This paper is a summary of the work carried out during the last two years in fuel burning measurements at RECH-1 for different enrichments, cooling times and burning rates. The measurements were made in two gamma-spectrometric facilities, one is installed in a hot cell and the other inside of the secondary pool of the RECH-1, where the element is under 2 meters of water. The hot cell measurements need at least 100 cooling days because of the problems generated by the transport of highly active fuel elements from the Reactor to the cell. This was the main reason for using the in-pool facility because of its capability to measure the burning of fuel elements without having to wait so long, that is with only 5 cooling days. The accumulated experience in measurements achieved in both facilities and the encouraging results show that this measuring method is reliable. The results agreed well with those obtained using the reactor's physics codes, which was the way they were obtained previously (Cw)

  15. Experimental method research on neutron equal dose-equivalent detection

    International Nuclear Information System (INIS)

    Ji Changsong

    1995-10-01

    The design principles of neutron dose-equivalent meter for neutron biological equi-effect detection are studied. Two traditional principles 'absorption net principle' and 'multi-detector principle' are discussed, and on the basis of which a new theoretical principle for neutron biological equi-effect detection--'absorption stick principle' has been put forward to place high hope on both increasing neutron sensitivity of this type of meters and overcoming the shortages of the two traditional methods. In accordance with this new principle a brand-new model of neutron dose-equivalent meter BH3105 has been developed. Its neutron sensitivity reaches 10 cps/(μSv·h -1 ), 18∼40 times higher than that of all the same kinds of meters 0.23∼0.56 cps/(μSv·h -1 ), available today at home and abroad and the specifications of the newly developed meter reach or surpass the levels of the same kind of meters. Therefore the new theoretical principle of neutron biological equi-effect detection--'absorption stick principle' is proved to be scientific, advanced and useful by experiments. (3 refs., 3 figs., 2 tabs.)

  16. Calculation-experimental method justifies the life of wagons

    Directory of Open Access Journals (Sweden)

    Валерія Сергіївна Воропай

    2015-11-01

    Full Text Available The article proposed a method to evaluate the technical state of tank wagons operating in chemical industry. An algorithm for evaluation the technical state of tank wagons was developed, that makes it possible on the basis of diagnosis and analysis of current condition to justify a further period of operation. The complex of works on testing the tanks and mathematical models for calculations of the design strength and reliability were proposed. The article is devoted to solving the problem of effective exploitation of the working fleet of tank wagons. Opportunities for further exploitation of cars, the complex of works on the assessment of their technical state and the calculation of the resources have been proposed in the article. Engineering research of the chemical industries park has reduced the shortage of the rolling stock for transportation of ammonia. The analysis of the chassis numerous faults and the main elements of tank wagons supporting structure after 20 years of exploitation was made. The algorithm of determining the residual life of the specialized tank wagons operating in an industrial plant has been proposed. The procedure for resource conservation of tank wagons carrying cargo under high pressure was first proposed. The improved procedure for identifying residual life proposed in the article has both theoretical and practical importance

  17. Experimental innovations in surface science a guide to practical laboratory methods and instruments

    CERN Document Server

    Yates, John T

    2015-01-01

    This book is a new edition of a classic text on experimental methods and instruments in surface science. It offers practical insight useful to chemists, physicists, and materials scientists working in experimental surface science. This enlarged second edition contains almost 300 descriptions of experimental methods. The more than 50 active areas with individual scientific and measurement concepts and activities relevant to each area are presented in this book. The key areas covered are: Vacuum System Technology, Mechanical Fabrication Techniques, Measurement Methods, Thermal Control, Delivery of Adsorbates to Surfaces, UHV Windows, Surface Preparation Methods, High Area Solids, Safety. The book is written for researchers and graduate students.

  18. A New Energy-Efficient Data Transmission Scheme Based on DSC and Virtual MIMO for Wireless Sensor Network

    OpenAIRE

    Li, Na; Zhang, Liwen; Li, Bing

    2015-01-01

    Energy efficiency in wireless sensor network (WSN) is one of the primary performance parameters. For improving the energy efficiency of WSN, we introduce distributed source coding (DSC) and virtual multiple-input multiple-output (MIMO) into wireless sensor network and then propose a new data transmission scheme called DSC-MIMO. DSC-MIMO compresses the source data using distributed source coding before transmitting, which is different from the existing communication schemes. Data compression c...

  19. Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship – Quasi-Experimental Designs

    Science.gov (United States)

    Schweizer, Marin L.; Braun, Barbara I.; Milstone, Aaron M.

    2016-01-01

    Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt non-randomized interventions. Quasi-experimental studies can be categorized into three major types: interrupted time series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. PMID:27267457

  20. Thermal analysis on parchments I: DSC and TGA combined approach for heat damage assessment

    DEFF Research Database (Denmark)

    Fessas, D.; Signorelli, M.; Schiraldi, A.

    2006-01-01

    Ancient, new and artificially aged parchments were investigated with both differential scanning calorimetry (DSC) and thermogravimetry (TGA). Criteria to define a quantitative ranking of the damage experienced by the bulk collagen of historical parchments were assessed. A damage-related correlation...

  1. Morphology evaluation of biodegradable copolyesters based on dimerized fatty acid studied by DSC, SAXS and WAXS

    Czech Academy of Sciences Publication Activity Database

    Kozlowska, A.; Gromadzki, Daniel; El Fray, M.; Štěpánek, Petr

    2008-01-01

    Roč. 16, č. 6 (2008), s. 85-88 ISSN 1230-3666 Institutional research plan: CEZ:AV0Z40500505 Keywords : multiblock copolymers * DSC * WAXS Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.439, year: 2008

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

    DEFF Research Database (Denmark)

    Borch, Kim; Cruys-Bagger, Nicolaj; Badino, Silke Flindt

    2014-01-01

    This work shows that differential scanning calorimetry (DSC) can be used to monitor the stability of substrate-adsorbed cellulases during long-term hydrolysis of insoluble cellulose. Thermal transitions of adsorbed enzyme were measured regularly in subsets of a progressing hydrolysis, and the size...

  3. Rapid examination of the kinetic process of intramolecular lactamization of gabapentin using DSC-FTIR

    International Nuclear Information System (INIS)

    Hsu, C.-H.; Lin, S.-Y.

    2009-01-01

    The thermal stability and thermodynamics of gabapentin (GBP) in the solid state were investigated by DSC and TG techniques, and FTIR microspectroscopy. The detailed intramolecular lactamization process of GBP to form gabapentin-lactam (GBP-L) was also determined by thermal FTIR microspectroscopy. GBP exhibited a DSC endothermic peak at 169 deg. C. The weight loss in TG curve of GBP suggested that the evaporation process of water liberated via intramolecular lactamization was simultaneously combined with the evaporation process of GBP-L having a DSC endothermic peak at 91 deg. C. A thermal FTIR microspectroscopy clearly evidenced the IR spectra at 3350 cm -1 for water liberated and at 1701 cm -1 for lactam structure formed due to the lactam formation of GBP. This study indicates that the activation energy for combined processes of intramolecular lactamization of GBP and evaporation of GBP-L was about 114.3 ± 23.3 kJ/mol, but for the evaporation of GBP-L alone was 76.2 ± 1.5 kJ/mol. A powerful simultaneous DSC-FTIR combined technique was easily used to quickly examine the detailed kinetic processes of intramolecular cyclization of GPB and evaporation of GBP-L in the solid state

  4. A method of sub-critical experimentation, 'the neutrostat'; Une methode d'experimentation sous critique 'le neutrostat'

    Energy Technology Data Exchange (ETDEWEB)

    Martelly, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The method proposed is designed for the study of neutronic properties of a sample (its material buckling, for example) and consists in submitting the sample to uniform surface density irradiation, its surface being a sphere or a cylinder which is supposed, temporarily, to be infinite. Neutron density in the sample will thus be uniform if its laplacian is nil: any curve in the distribution clearly indicating its absorbent or multiplying properties. In the case of a sample with multiplying power, density is identical to that in an active core, thus measurement of buckling will be free from considerable systematic error causes. The thermic equivalent of this type of irradiation would be a thermostat with an external heat source distributed uniformly over its surface: its temperature would be uniform. It is this analogy that has led us to baptize it the 'Neutrostat'. (author)Fren. [French] En vue d'etudier les proprietes neutroniques d'un milieu (son laplacien 'matiere' par exemple), la methode proposee consiste a le soumettre a des conditions d'irradiation uniforme sur sa surface, celle-ci ayant la forme d'une sphere ou d'un cylindre que nous supposons provisoirement infini. Les neutrons s'y trouvent alors repartis avec une densite uniforme si le milieu est un diffuseur pur. Toute courbure de cette repartition sera un indice sensible de ses proprietes absorbantes ou multiplicatrices. Dans le cas d'un milieu multiplicateur, la repartition est identique a celle qui regne au milieu d'une pile critique et nous verrons que la mesure du laplacien est alors exempte de causes d'erreurs systematiques importantes. L'equivalent thermique d'un tel mode d'irradiation serait un dispositif thermostatique dont la source de chaleur externe serait repartie uniformement sur la surface: il y regnerait une temperature uniforme. C'est cette analogie qui nous a guides dans le choix du vocable propose dans le titre: 'Neutrostat'. (auteur)

  5. Experimental Results and Numerical Simulation of the Target RCS using Gaussian Beam Summation Method

    Directory of Open Access Journals (Sweden)

    Ghanmi Helmi

    2018-05-01

    Full Text Available This paper presents a numerical and experimental study of Radar Cross Section (RCS of radar targets using Gaussian Beam Summation (GBS method. The purpose GBS method has several advantages over ray method, mainly on the caustic problem. To evaluate the performance of the chosen method, we started the analysis of the RCS using Gaussian Beam Summation (GBS and Gaussian Beam Launching (GBL, the asymptotic models Physical Optic (PO, Geometrical Theory of Diffraction (GTD and the rigorous Method of Moment (MoM. Then, we showed the experimental validation of the numerical results using experimental measurements which have been executed in the anechoic chamber of Lab-STICC at ENSTA Bretagne. The numerical and experimental results of the RCS are studied and given as a function of various parameters: polarization type, target size, Gaussian beams number and Gaussian beams width.

  6. Distinct roles of the DmNav and DSC1 channels in the action of DDT and pyrethroids.

    Science.gov (United States)

    Rinkevich, Frank D; Du, Yuzhe; Tolinski, Josh; Ueda, Atsushi; Wu, Chun-Fang; Zhorov, Boris S; Dong, Ke

    2015-03-01

    Voltage-gated sodium channels (Nav channels) are critical for electrical signaling in the nervous system and are the primary targets of the insecticides DDT and pyrethroids. In Drosophila melanogaster, besides the canonical Nav channel, Para (also called DmNav), there is a sodium channel-like cation channel called DSC1 (Drosophila sodium channel 1). Temperature-sensitive paralytic mutations in DmNav (para(ts)) confer resistance to DDT and pyrethroids, whereas DSC1 knockout flies exhibit enhanced sensitivity to pyrethroids. To further define the roles and interaction of DmNav and DSC1 channels in DDT and pyrethroid neurotoxicology, we generated a DmNav/DSC1 double mutant line by introducing a para(ts1) allele (carrying the I265N mutation) into a DSC1 knockout line. We confirmed that the I265N mutation reduced the sensitivity to two pyrethroids, permethrin and deltamethrin of a DmNav variant expressed in Xenopus oocytes. Computer modeling predicts that the I265N mutation confers pyrethroid resistance by allosterically altering the second pyrethroid receptor site on the DmNav channel. Furthermore, we found that I265N-mediated pyrethroid resistance in para(ts1) mutant flies was almost completely abolished in para(ts1);DSC1(-/-) double mutant flies. Unexpectedly, however, the DSC1 knockout flies were less sensitive to DDT, compared to the control flies (w(1118A)), and the para(ts1);DSC1(-/-) double mutant flies were even more resistant to DDT compared to the DSC1 knockout or para(ts1) mutant. Our findings revealed distinct roles of the DmNav and DSC1 channels in the neurotoxicology of DDT vs. pyrethroids and implicate the exciting possibility of using DSC1 channel blockers or modifiers in the management of pyrethroid resistance. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Scaffolded Instruction Improves Student Understanding of the Scientific Method & Experimental Design

    Science.gov (United States)

    D'Costa, Allison R.; Schlueter, Mark A.

    2013-01-01

    Implementation of a guided-inquiry lab in introductory biology classes, along with scaffolded instruction, improved students' understanding of the scientific method, their ability to design an experiment, and their identification of experimental variables. Pre- and postassessments from experimental versus control sections over three semesters…

  8. LEARNING TO READ SCIENTIFIC RUSSIAN BY THE THREE QUESTION EXPERIMENTAL (3QX) METHOD.

    Science.gov (United States)

    ALFORD, M.H.T.

    A NEW METHOD FOR LEARNING TO READ TECHNICAL LITERATURE IN A FOREIGN LANGUAGE IS BEING DEVELOPED AND TESTED AT THE LANGUAGE CENTRE OF THE UNIVERSITY OF ESSEX, COLCHESTER, ENGLAND. THE METHOD IS CALLED "THREE QUESTION EXPERIMENTAL METHOD (3QX)," AND IT HAS BEEN USED IN THREE COURSES FOR TEACHING SCIENTIFIC RUSSIAN TO PHYSICISTS. THE THREE…

  9. AN EXPERIMENTAL ASSESSMENT OF THE PLATE HEAT EXCHANGER CHARACTERISTICS BY WILSON PLOT METHOD

    Directory of Open Access Journals (Sweden)

    Jan Opatřil

    2016-10-01

    Full Text Available An aim of this paper is suggestion of the evaluation method based on the experimental data and the Wilson plot method for the Plate Heat Exchangers (PHE. For the purpose of the project the new experimental loop was built for the testing of PHE to obtain the overhaul heat transfer coefficient and pressure drop between inlet and outlet of the fluid. The measurement were done for three different PHE with the performance range 30-100kW. The working fluid was water on both sides of the PHE. The differences are in number of pates as well as in extrusion profiles. The Wilson plot evaluation method was involved for the processing experimental data. To obtain more accurate correlations between the experimental data and theoretical results yield of the Wilson plot, the method was enhanced by the measured pressure drop involving. This approach could be useful for PHE designing software and for the manufacturing company.

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

    KAUST Repository

    Long, Quan; Scavino, Marco; Tempone, Raul; Wang, Suojin

    2014-01-01

    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

  11. A DSC study of zinc binding to bovine serum albumin (BSA

    Directory of Open Access Journals (Sweden)

    SANJA OSTOJIC

    2007-04-01

    Full Text Available The thermal denaturation of bovine serum albumin (BSA is a kinetically and thermodynamically controlled process. The effects of zinc binding to bovine serum albumin (BSA, followed by differential scanning calorimetry (DSC, were investigated in this work, with the purpose of obtaining a better understanding of the albumin/zinc interaction. From the DSC curves, the thermodynamic parameters of protein denaturation were obtained, i.e., the temperature of thermal transition maximum (Tm, calorimetric enthalpy (DHcal, van't Hoff enthalpy (DHvH, the number of binding sites (I, II, the binding constants for each binding site (KbI, KbII and the average number of ligands bound per mole of native protein XN. The thermodynamic data of protein unfolding showed that zinc binding to bovine serum albumin increases the stability of the protein (higher values of DHcal and the different ratio DHcal/DHvH indicates the perturbation of the protein during thermal denaturation.

  12. Melting temperature and enthalpy variations of phase change materials (PCMs): a differential scanning calorimetry (DSC) analysis

    Science.gov (United States)

    Sun, Xiaoqin; Lee, Kyoung Ok; Medina, Mario A.; Chu, Youhong; Li, Chuanchang

    2018-06-01

    Differential scanning calorimetry (DSC) analysis is a standard thermal analysis technique used to determine the phase transition temperature, enthalpy, heat of fusion, specific heat and activation energy of phase change materials (PCMs). To determine the appropriate heating rate and sample mass, various DSC measurements were carried out using two kinds of PCMs, namely N-octadecane paraffin and calcium chloride hexahydrate. The variations in phase transition temperature, enthalpy, heat of fusion, specific heat and activation energy were observed within applicable heating rates and sample masses. It was found that the phase transition temperature range increased with increasing heating rate and sample mass; while the heat of fusion varied without any established pattern. The specific heat decreased with the increase of heating rate and sample mass. For accuracy purpose, it is recommended that for PCMs with high thermal conductivity (e.g. hydrated salt) the focus will be on heating rate rather than sample mass.

  13. Recent advances and potential applications of modulated differential scanning calorimetry (mDSC) in drug development

    DEFF Research Database (Denmark)

    Knopp, Matthias Manne; Löbmann, Korbinian; Elder, David P.

    2016-01-01

    Differential scanning calorimetry (DSC) is frequently the thermal analysis technique of choice within preformulation and formulation sciences because of its ability to provide detailed information about both the physical and energetic properties of a substance and/or formulation. However, convent......-dried formulations. However, as discussed in the present review, a number of other potential applications could also be relevant for the pharmaceutical scientist....

  14. Raman and DSC studies of fragility in tellurium-zinc oxide glass formers

    International Nuclear Information System (INIS)

    Stavrou, Elissaios; Kripotou, Sotiria; Raptis, Constantine; Turrell, Sylvia; Syassen, Karl

    2011-01-01

    Raman scattering and differential scanning calorimetry (DSC) measurements have been carried out in four mixed (TeO 2 ) 1-x (ZnO) x (x = 0.1, 0.2, 0.3, 0.4) glasses at high temperatures (Raman and DSC through the glass transition) and high pressures (Raman) with the aim of determining the fragility of these glass forming oxides. Four different criteria, corresponding to four parameters, were applied to assess the fragility of the glasses. From the DSC studies, we have obtained the fragility parameter m which corresponds to the slopes of Arrhenius (lnQ vs. 1/T g , were Q is the heating rate) plots, and the glass transition width ΔT g . Also, from the low-frequency Raman scattering, and in particular the boson peak intensity of the glasses at T g , we have estimated the fragility ratio r R (T g ) = I min /I max whose value serves as another (empirical) fragility criterion. Finally, from high pressure Raman measurements on the glasses, we have estimated the Grueneisen parameter γ T for each glass, which constitutes the fourth fragility parameter adopted in this work. Considering the four parameters ΔT g , m, r (T g ) and γ T and the generally accepted (empirical) fragility criteria, we conclude that the mixed tellurium-zinc oxides constitute strong-to-intermediate glass formers (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. LIQUID COAL CHARACTERISTIC ANALYSIS WITH FOURIER TRANSFORM INFRA RED (FTIR AND DIFFERENTIAL SCANNING CALORIMETER (DSC

    Directory of Open Access Journals (Sweden)

    ATUS BUKU

    2017-02-01

    Full Text Available The aim of this study is to identify the value of compounds contained in liquid coal by using Fourier Transform Infra-Red (FTIR and Differential Scanning Calorimeter (DSC. FTIR was used to analyse the components contained in liquid coal, while the DSC is done to observe the heat reaction to the environment. Based on the Fourier Transform Infra-Red (FTIR test results it is shown that the compound contained in the liquid Coal consisting of alkanes, alkenes and alkyne. These compounds are similar compounds. The alkanes, alkenes and alkynes compounds undergo complete combustion reaction with oxygen and would produce CO2 and water vapour [H2O (g]. If incomplete combustion occurs, the reaction proceeds in the form of Carbon Monoxide CO gas or solid carbon andH2O. Combustion reaction that occurs in all these three compounds also produces a number of considerable energy. And if it has higher value of Carbon then the boiling point would be higher. From the Differential Scanning Calorimetric (DSC test results obtained some of the factors that affect the reaction speed, which are the temperature, the reaction mixture composition, and pressure. Temperature has a profound influence in coal liquefaction, because if liquid coal heated with high pressure, the carbon chain would break down into smaller chains consisting of aromatic chain, hydro-aromatic, or aliphatic. This then triggers a reaction between oil formation and polymerization reactions to form solids (char.

  16. Contribution of modulated DSc to study the thermal behaviour of PET films drawn in hot water

    International Nuclear Information System (INIS)

    Zumalian, Abubaker

    2003-01-01

    PET films uni-axially drawn in hot water are studied by means of conventional DSc and modulated DSc. The glass transition is studied by modulated DSc which allows access to the values of the glass transition temperature T g and the variations of δ C p = C p 1-C p g (difference between thermal capacity in the liquid-like and glassy states at T = T g ). Variations of T g with the water content (which act as plasticizer) and with the drawing (which rigidifies the amorphous phase) are discussed in regard to the structure engaged in these materials. The variations of δ C p are also interpreted with the help of a three phase model and a strong-fragile glass former liquid concept. We show that the fragility of the medium increases by the conjugated effects of deformation and water as soon as a strain induced crystalline phase is obtained, and it decreases drastically when the rigid amorphous phase occurs. (author)

  17. Utilisation de la DSC pour la caractérisation de la stabilité des émulsions eau dans pétrole Use of the Dsc Technique to Characterize Water-In-Crude Oil Emulsions Stability

    Directory of Open Access Journals (Sweden)

    Dalmazzone C.

    2006-12-01

    the assessment of emulsions stability. They are generally based on the analysis of the droplets size distribution. Unfortunately, most of the usual techniques can not be applied to opaque water-in-oil emulsions. The most useful method to characterize the stability of emulsions is of course the bottle test . It consists in monitoring the extent of phase separation with time. This type of test provides a significant amount of information relating to both the stability of the emulsion phase and the clarity of the separated water, but it is very empirical. The DSC technique is generally used to determine the composition of water-in-oil emulsions. It is the only technique capable of distinguishing free water from emulsified water. It was shown in this study that it is a very useful technique, which allows the study of the evolution of the droplet size distribution as well as a precise determination of the water content.

  18. An evaluation of the use of modulated temperature DSC as a means of assessing the relaxation behaviour of amorphous lactose.

    Science.gov (United States)

    Craig, D Q; Barsnes, M; Royall, P G; Kett, V L

    2000-06-01

    To evaluate the use of Modulated Temperature DSC (MTDSC) as a means of assessing the relaxation behaviour of amorphous lactose via measurement of the heat capacity, glass transition (Tg) and relaxation endotherm. Samples of amorphous lactose were prepared by freeze drying. MTDSC was conducted using a TA Instruments 2920 MDSC using a heating rate of 2 degrees C/minute, a modulation amplitude of +/-0.3 degrees C and a period of 60 seconds. Samples were cycled by heating to 140 degrees C and cooling to a range of annealing temperatures between 80 degrees C and 100 degrees C, followed by reheating through the Tg region. Systems were then recooled to allow for correction of the Tg shift effect. MTDSC enabled separation of the glass transition from the relaxation endotherm, thereby facilitating calculation of the relaxation time as a function of temperature. The relative merits of using MTDSC for the assessment of relaxation processes are discussed. In addition, the use of the fictive temperature rather than the experimentally derived Tg is outlined. MTDSC allows assessment of the glass transition temperature, the magnitude of the relaxation endotherm and the value of the heat capacity, thus facilitating calculation of relaxation times. Limitations identified with the approach include the slow scanning speed, the need for careful choice of experimental parameters and the Tg shift effect.

  19. 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...

  20. Experimental validation for calcul methods of structures having shock non-linearity

    International Nuclear Information System (INIS)

    Brochard, D.; Buland, P.

    1987-01-01

    For the seismic analysis of non-linear structures, numerical methods have been developed which need to be validated on experimental results. The aim of this paper is to present the design method of a test program which results will be used for this purpose. Some applications to nuclear components will illustrate this presentation [fr

  1. Ultrasonic wave propagation through aberrating layers: experimental verification of the conjugate gradient Rayleigh method

    NARCIS (Netherlands)

    Ledoux, L.A.F.; Berkhoff, Arthur P.; Thijssen, J.M.

    The Conjugate Gradient Rayleigh method for the calculation of acoustic reflection and transmission at a rough interface between two media was experimentally verified. The method is based on a continuous version of the conjugate gradient technique and plane-wave expansions. We measured the beam

  2. Survey of engineering computational methods and experimental programs for estimating supersonic missile aerodynamic characteristics

    Science.gov (United States)

    Sawyer, W. C.; Allen, J. M.; Hernandez, G.; Dillenius, M. F. E.; Hemsch, M. J.

    1982-01-01

    This paper presents a survey of engineering computational methods and experimental programs used for estimating the aerodynamic characteristics of missile configurations. Emphasis is placed on those methods which are suitable for preliminary design of conventional and advanced concepts. An analysis of the technical approaches of the various methods is made in order to assess their suitability to estimate longitudinal and/or lateral-directional characteristics for different classes of missile configurations. Some comparisons between the predicted characteristics and experimental data are presented. These comparisons are made for a large variation in flow conditions and model attitude parameters. The paper also presents known experimental research programs developed for the specific purpose of validating analytical methods and extending the capability of data-base programs.

  3. Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Quasi-Experimental Designs.

    Science.gov (United States)

    Schweizer, Marin L; Braun, Barbara I; Milstone, Aaron M

    2016-10-01

    Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt, nonrandomized interventions. Quasi-experimental studies can be categorized into 3 major types: interrupted time-series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship, including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. Infect Control Hosp Epidemiol 2016;1-6.

  4. TG-DSC method applied to drying characteristics of areca inflorescence during drying

    Science.gov (United States)

    Song, Fei; Wang, Hui; Huang, Yulin; Zhang, Yufeng; Chen, Weijun; Zhao, Songlin; Zhang, Ming

    2017-10-01

    In this study, suitability of eight drying models available in literature on defining drying characteristics of areca inflorescence has been examined by non-linear regression analysis using the Statistic Computer Program. The coefficient of determination ( R 2 ) and the reduced chi-square (χ2) are used as indicators to evaluate the best suitable model. According to the results, the Verma et al. model gave the best results for explaining the drying characteristics of areca inflorescence. The drying process could be divided into three periods: rising rate, constant rate and the falling rate period. Fick's second law can describe the moisture transport during the food drying process that takes place in the falling rate period. The values of effective diffusivity during the drying of areca inflorescence ranged from 2.756 × 10-7 to 6.257 × 10-7 m2/s and the activation energy was tested for 35.535 kJ/mol. The heat requirement of areca inflorescence at 40-60 °C was calculated from 50.57 to 60.50 kJ/kg during the drying process.

  5. Coherent versus incoherent resonant emission: an experimental method for easy discrimination and measurement

    Science.gov (United States)

    Ceccherini, S.; Colocci, M.; Gurioli, M.; Bogani, F.

    1998-11-01

    The distinction between the coherent and the incoherent component of the radiation emitted from resonantly excited material systems is difficult experimentally, particularly when ultra-short optical pulses are used for excitation. We propose an experimental procedure allowing an easy measurement of the two components. The method is completely general and applicable to any kind of physical system; its feasibility is demonstrated on the resonant emission from excitons in a semiconductor quantum well.

  6. Experimental Verification of a Simple Method for Accurate Center of Gravity Determination of Small Satellite Platforms

    Directory of Open Access Journals (Sweden)

    Dario Modenini

    2018-01-01

    Full Text Available We propose a simple and relatively inexpensive method for determining the center of gravity (CoG of a small spacecraft. This method, which can be ascribed to the class of suspension techniques, is based on dual-axis inclinometer readings. By performing two consecutive suspensions from two different points, the CoG is determined, ideally, as the intersection between two lines which are uniquely defined by the respective rotations. We performed an experimental campaign to verify the method and assess its accuracy. Thanks to a quantitative error budget, we obtained an error distribution with simulations, which we verified through experimental tests. The retrieved experimental error distribution agrees well with the results predicted through simulations, which in turn lead to a CoG error norm smaller than 2 mm with 95% confidence level.

  7. Experimental and mathematical modeling methods for the investigation of toxicological interactions

    International Nuclear Information System (INIS)

    El-Masri, Hisham A.

    2007-01-01

    While procedures have been developed and used for many years to assess risk and determine acceptable exposure levels to individual chemicals, most cases of environmental contamination can result in concurrent or sequential exposure to more than one chemical. Toxicological predictions of such combinations must be based on an understanding of the mechanisms of action and interaction of the components of the mixtures. Statistical and experimental methods test the existence of toxicological interactions in a mixture. However, these methods are limited to experimental data ranges for which they are derived, in addition to limitations caused by response differences from experimental animals to humans. Empirical methods such as isobolograms, median-effect principle and response surface methodology (RSM) are based on statistical experimental design and regression of data. For that reason, the predicted response surfaces can be used for extrapolation across dose regions where interaction mechanisms are not anticipated to change. In general, using these methods for predictions can be problematic without including biologically based mechanistic descriptions that can account for dose and species differences. Mechanistically based models, such as physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models, include explicit descriptions of interaction mechanisms which are related to target tissues levels. These models include dose-dependent mechanistic hypotheses of toxicological interactions which can be tested by model-directed experimental design and used to identify dose regions where interactions are not significant

  8. CISM-Course on Modern Optical Methods in Experimental Solid Mechanics

    CERN Document Server

    2000-01-01

    The book covers the theories and physics of advanced new optical measuring methods and problems of experimental performance, recent achievements in the basic interferometric methods holography, speckle-interferometry, shearography as well as linear/non-linear photoelasticity and photoviscoelasticity, Moiré- and grid-techniques. It deals with theory and application of digital image processing, methods of data recording, data processing and -visualisation, with mathematical/numerical procedures for final evaluation of digitised measured data and the principle of hybrid techniques. It introduces into the new perceptions of methods in experimental solid mechanics and it should encourage scientists to deal intensively with the theories for further developments, and enables practitioners, to understand theory and physics of the new achievements at least and to apply the methods in research als well as in developments in practice.

  9. A comparative study to investigate burnup in research reactor fuel using two independent experimental methods

    International Nuclear Information System (INIS)

    Iqbal, M.; Mehmood, T.; Ayazuddin, S.K.; Salahuddin, A.; Pervez, S.

    2001-01-01

    Two independent experimental methods have been used for the comparative study of fuel burnup measurement in low enriched uranium, plate type research reactor. In the first method a gamma ray activity ratio method was employed. An experimental setup was established for gamma ray scanning using prior calibrated high purity germanium detector. The computer software KORIGEN gave the theoretical support. In the second method reactivity difference technique was used. At the same location in the same core configuration the fresh and burned fuel element's reactivity worth was estimated. For theoretical estimated curve, group cross-sections were generated using computer code WIMS-D/4, and three dimensional modeling was made by computer code CITATION. The measured burnup of different fuel elements using these methods were found to be in good agreement

  10. Validation of Experimental whole-body SAR Assessment Method in a Complex Indoor Environment

    DEFF Research Database (Denmark)

    Bamba, Aliou; Joseph, Wout; Vermeeren, Gunter

    2012-01-01

    Assessing experimentally the whole-body specific absorption rate (SARwb) in a complex indoor environment is very challenging. An experimental method based on room electromagnetics theory (accounting only the Line-Of-Sight as specular path) to assess the whole-body SAR is validated by numerical...... of the proposed method is that it allows discarding the computation burden because it does not use any discretizations. Results show good agreement between measurement and computation at 2.8 GHz, as long as the plane wave assumption is valid, i.e., for high distances from the transmitter. Relative deviations 0...

  11. Reverse Schreinemakers Method for Experimental Analysis of Mixed-Solvent Electrolyte Systems

    DEFF Research Database (Denmark)

    Fosbøl, Philip Loldrup; Thomsen, Kaj; Stenby, Erling Halfdan

    2009-01-01

    the reverse Schreinemakers (RS) method. The method is based on simple mass balance principles similar to the wet residues method. It allows for accurate determination of the mixed-solvent phase composition even though part of the solvent may precipitate as complexes between solvent and salt. Discrepancies......A method based on Schreinemakers's tie-line theory of 1893 is derived for determining the composition and phase amounts in solubility experiments for multi-solvent electrolyte systems. The method uses the lever rule in reverse compared to Schreinemakers's wet residue method, and is therefore called...... from determining the composition of salt mixtures by pH titration are discussed, and the derived method significantly improves the obtained result from titration. Furthermore, the method reduces the required experimental work needed for analysis of phase composition. The method is applicable to multi...

  12. COMPARATIVE KINETICS STUDY OF THE THERMAL AND THERMO-OXIDATIVE DEGRADATION OF A POLYSTYRENE-CLAY NANOCOMPOZITE BY TGA AND DSC

    Directory of Open Access Journals (Sweden)

    Ion Dranca

    2010-12-01

    Full Text Available The methods of thermogravimetry (TGA and differential scanning calorimetry (DSC have been used to study the thermal and thermo-oxidative degradation of polystyrene (PS and a PS-clay nanocomposite. An advanced isoconversional method has been applied for kinertic analysis. Introduction of the clay phase increasers the activation energy and affects the total heat of degradation, which suggests a change in the reaction mechanism. The obtained kinetic data permit a comparative assessment of the fire resistance of the studied materials

  13. A Normalized Transfer Matrix Method for the Free Vibration of Stepped Beams: Comparison with Experimental and FE(3D Methods

    Directory of Open Access Journals (Sweden)

    Tamer Ahmed El-Sayed

    2017-01-01

    Full Text Available The exact solution for multistepped Timoshenko beam is derived using a set of fundamental solutions. This set of solutions is derived to normalize the solution at the origin of the coordinates. The start, end, and intermediate boundary conditions involve concentrated masses and linear and rotational elastic supports. The beam start, end, and intermediate equations are assembled using the present normalized transfer matrix (NTM. The advantage of this method is that it is quicker than the standard method because the size of the complete system coefficient matrix is 4 × 4. In addition, during the assembly of this matrix, there are no inverse matrix steps required. The validity of this method is tested by comparing the results of the current method with the literature. Then the validity of the exact stepped analysis is checked using experimental and FE(3D methods. The experimental results for stepped beams with single step and two steps, for sixteen different test samples, are in excellent agreement with those of the three-dimensional finite element FE(3D. The comparison between the NTM method and the finite element method results shows that the modal percentage deviation is increased when a beam step location coincides with a peak point in the mode shape. Meanwhile, the deviation decreases when a beam step location coincides with a straight portion in the mode shape.

  14. A new experimental design method to optimize formulations focusing on a lubricant for hydrophilic matrix tablets.

    Science.gov (United States)

    Choi, Du Hyung; Shin, Sangmun; Khoa Viet Truong, Nguyen; Jeong, Seong Hoon

    2012-09-01

    A robust experimental design method was developed with the well-established response surface methodology and time series modeling to facilitate the formulation development process with magnesium stearate incorporated into hydrophilic matrix tablets. Two directional analyses and a time-oriented model were utilized to optimize the experimental responses. Evaluations of tablet gelation and drug release were conducted with two factors x₁ and x₂: one was a formulation factor (the amount of magnesium stearate) and the other was a processing factor (mixing time), respectively. Moreover, different batch sizes (100 and 500 tablet batches) were also evaluated to investigate an effect of batch size. The selected input control factors were arranged in a mixture simplex lattice design with 13 experimental runs. The obtained optimal settings of magnesium stearate for gelation were 0.46 g, 2.76 min (mixing time) for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The optimal settings for drug release were 0.33 g, 7.99 min for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The exact ratio and mixing time of magnesium stearate could be formulated according to the resulting hydrophilic matrix tablet properties. The newly designed experimental method provided very useful information for characterizing significant factors and hence to obtain optimum formulations allowing for a systematic and reliable experimental design method.

  15. DTA and DSC study on the effect of mechanical dispersion on poly(tetrafluorethylene properties

    Directory of Open Access Journals (Sweden)

    Dumitraşa Mihai

    2014-12-01

    Full Text Available Poly(tetrafluorethylene particles were obtained by mechanical processing of the formed polymer (Teflon bar. In order to assess the effect of mechanical wear on polymer properties, their melting and crystallization behaviour was investigated by DSC and DTA, and the results were compared to the ones obtained for the native polymer. An increase of the crystallinity degree and an accentuated decrease of the average molecular weight were found for the samples submitted to mechanical wear, as a result of mechanical degradation of the polymer

  16. Stochastic temperature modulation: A new technique in temperature-modulated DSC

    International Nuclear Information System (INIS)

    Schawe, J.E.K.; Huetter, T.; Heitz, C.; Alig, I.; Lellinger, D.

    2006-01-01

    A new temperature-modulated differential scanning calorimetry (TMDSC) technique is introduced. The technique is based on stochastic temperature modulation and has been developed as a consequence of a generalized theory of a temperature-modulated DSC. The quasi-static heat capacity and the frequency-dependent complex heat capacity can be determined over a wide frequency range in one single measurement without further calibration. Furthermore, the reversing and non-reversing heat flows are determined directly from the measured data. Examples show the frequency dependence of the glass transition, the isothermal curing of thermosets and a solid-solid transition

  17. Study of thermal transitions in polymers by a multifrequency modulated DSC technique

    OpenAIRE

    Fraga Rivas, Iria

    2010-01-01

    Premi extraordinari doctorat curs 2009-2010, àmbit de Ciències Differential Scanning Calorimetry (DSC) is one of the most widely used thermal analysis techniques for the study of transitions and relaxation processes in polymers and also in other materials. It measures the heat flow as a function of time and/or temperature, and determines the energy released or absorbed by a sample when it is heated (cooled) or maintained at a constant temperature. Its advantages are that it is fast a...

  18. Experimental methods of investigation of kinetics and dynamics of nuclear reactors

    International Nuclear Information System (INIS)

    Costa Oliveira, Jaime M.

    1969-03-01

    The author presents experimental methods used to study kinetic and dynamic properties of nuclear reactors. Kinetic methods aim at determining characteristic parameters of the behaviour in time of neutrons. Dynamic methods aim at establishing the relationships between the reactor behaviour and its internal and external causes (notably the measurement of transfer functions). The author proposes a classification with respect to the excitation type: periodic excitation (reactivity sinusoidal modulation, source sinusoidal modulation, periodic pulse excitation), non periodic excitation (reactivity monitoring, reactivity linear variation, reactivity variation according to any given law, removal of starting source), random excitation (random reactivity or source excitation), natural fluctuations (alpha-Rossi method, methods of reduced variance, probabilistic methods, correlation methods, spectral analysis method). He also addresses space and energy effects. Applications are reported for low power and power reactors

  19. The detection of amorphous material in a nominally crystalline drug using modulated temperature DSC--a case study.

    Science.gov (United States)

    Saklatvala, R; Royall, P G; Craig, D Q

    1999-12-01

    Two batches (1 and 2) of an experimental drug (L7) which have shown marked differences in their chemical stability profiles were examined with a view to identifying the presence of small quantities of amorphous material using modulated temperature DSC (MTDSC). The external morphological characteristics of the two batches were similar although marked differences were seen in the moisture uptake profiles. MTDSC studies indicated that while no evidence for a glass transition could be seen for Batch 1, a T(g) and accompanying relaxation endotherm were observed for Batch 2. Comparison with a glassy form of the drug indicated that the amorphous content was in the region of 5-6% w/w in Batch 2. Dynamic moisture sorption studies indicated that while Batch 2 showed a higher uptake profile than Batch 1, addition of 5% w/w amorphous material to Batch 1 led to the establishment of a very similar profile to that seen for Batch 2. It was concluded that Batch 2 contains amorphous material which is responsible for the greater moisture uptake (and by implication poor chemical stability) of this sample and that the glass transition of this fraction may be characterised using MTDSC.

  20. Recent mouse and rat methods for the study of experimental oral candidiasis.

    Science.gov (United States)

    Costa, Anna C B P; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio O C

    2013-07-01

    The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis.

  1. Methods for experimental design principles and applications for physicists and chemists

    CERN Document Server

    Goupy, J

    1993-01-01

    A method for organizing and conducting scientific experiments is described in this volume which enables experimenters to reduce the number of trials run, while retaining all the parameters that may influence the result. The choice of ideal experiments is based on mathematical concepts, but the author adopts a practical approach and uses theory only when necessary. Written for experimenters by an experimenter, it is an introduction to the philosophy of scientific investigation. Researchers with limited time and resources at their disposal will find this text a valuable guide for solving specific problems efficiently. The presentation makes extensive use of examples, and the approach and methods are graphical rather than numerical. All calculations can be performed on a personal computer; readers are assumed to have no previous knowledge of the subject. The presentation is such that the beginner may acquire a thorough understanding of the basic concepts. However, there is also sufficient material to challenge t...

  2. Recent mouse and rat methods for the study of experimental oral candidiasis

    Science.gov (United States)

    Costa, Anna CBP; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio OC

    2013-01-01

    The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis. PMID:23715031

  3. Synergy between experimental and theoretical methods in the exploration of homogeneous transition metal catalysis

    DEFF Research Database (Denmark)

    Lupp, Daniel; Christensen, Niels Johan; Fristrup, Peter

    2014-01-01

    n this Perspective, we will focus on the use of both experimental and theoretical methods in the exploration of reaction mechanisms in homogeneous transition metal catalysis. We briefly introduce the use of Hammett studies and kinetic isotope effects (KIE). Both of these techniques can be complem......n this Perspective, we will focus on the use of both experimental and theoretical methods in the exploration of reaction mechanisms in homogeneous transition metal catalysis. We briefly introduce the use of Hammett studies and kinetic isotope effects (KIE). Both of these techniques can...... be complemented by computational chemistry – in particular in cases where interpretation of the experimental results is not straightforward. The good correspondence between experiment and theory is only possible due to recent advances within the applied theoretical framework. We therefore also highlight...

  4. Treating experimental data of inverse kinetic method by unitary linear regression analysis

    International Nuclear Information System (INIS)

    Zhao Yusen; Chen Xiaoliang

    2009-01-01

    The theory of treating experimental data of inverse kinetic method by unitary linear regression analysis was described. Not only the reactivity, but also the effective neutron source intensity could be calculated by this method. Computer code was compiled base on the inverse kinetic method and unitary linear regression analysis. The data of zero power facility BFS-1 in Russia were processed and the results were compared. The results show that the reactivity and the effective neutron source intensity can be obtained correctly by treating experimental data of inverse kinetic method using unitary linear regression analysis and the precision of reactivity measurement is improved. The central element efficiency can be calculated by using the reactivity. The result also shows that the effect to reactivity measurement caused by external neutron source should be considered when the reactor power is low and the intensity of external neutron source is strong. (authors)

  5. Methods of experimental settlement of contradicting data in evaluated nuclear data libraries

    Directory of Open Access Journals (Sweden)

    V. A. Libman

    2016-12-01

    Full Text Available The latest versions of the evaluated nuclear data libraries (ENDLs have contradictions concerning data about neutron cross sections. To resolve this contradiction we propose the method of experimental verification. This method is based on using of the filtered neutron beams and following measurement of appropriate samples. The basic idea of the method is to modify the suited filtered neutron beam so that the differences between the neutron cross sections in accordance with different ENDLs become measurable. Demonstration of the method is given by the example of cerium, which according to the latest versions of four ENDLs has significantly different total neutron cross section.

  6. A photocurrent compensation method of bipolar transistors under high dose rate radiation and its experimental research

    International Nuclear Information System (INIS)

    Yin Xuesong; Liu Zhongli; Li Chunji; Yu Fang

    2005-01-01

    Experiment using discrete bipolar transistors has been performed to verify the effect of the photocurrent compensation method. The theory of the dose rate effects of bipolar transistors and the photocurrent compensation method are introduced. The comparison between the response of hardened and unhardened circuits under high dose rate radiation is discussed. The experimental results show instructiveness to the hardness of bipolar integrated circuits under transient radiation. (authors)

  7. Experimental Methods Related to Coupled Fast-Thermal Systems at the RB Reactor

    International Nuclear Information System (INIS)

    Pesic, M.

    2002-01-01

    In addition to the review of RB reactor characteristics this presentation is focused on the coupled fast-thermal systems achieved at the reactor. The following experimental methods are presented: neutron spectra measurements; steady state experiments and kinetic measurements ( β eff ) related to the coupled fast-thermal cores

  8. The Experimental Stand for Research of Wakefield Method of Charged Particles Acceleration

    International Nuclear Information System (INIS)

    Kiselev, V.A.; Linnik, A.F.; Onishchenko, I.N.; Onishchenko, N.I.; Sotnikov, G.V.; Uskov, V.V.

    2006-01-01

    The experimental installation and diagnostic equipment with motivation to use for various researches of wakefield method of charged particles acceleration both in plasma and in dielectric structure has been described. The main parameters of a sequence of short relativistic electron bunch and values of physical characteristics of slow-down structures have been presented

  9. Experimental Sentinel-2 LAI estimation using parametric, non-parametric and physical retrieval methods - A comparison

    NARCIS (Netherlands)

    Verrelst, Jochem; Rivera, Juan Pablo; Veroustraete, Frank; Muñoz-Marí, Jordi; Clevers, J.G.P.W.; Camps-Valls, Gustau; Moreno, José

    2015-01-01

    Given the forthcoming availability of Sentinel-2 (S2) images, this paper provides a systematic comparison of retrieval accuracy and processing speed of a multitude of parametric, non-parametric and physically-based retrieval methods using simulated S2 data. An experimental field dataset (SPARC),

  10. Nicotinamides: Evaluation of thermochemical experimental properties

    International Nuclear Information System (INIS)

    Zhabina, Aleksandra A.; Nagrimanov, Ruslan N.; Emel’yanenko, Vladimir N.; Solomonov, Boris N.; Verevkin, Sergey P.

    2016-01-01

    Highlights: • Vapor pressures measured by transpiration method. • Enthalpies of solution measured using high-precision solution calorimetry. • Enthalpies of fusion measured by DSC. • Sublimation enthalpies derived from transpiration and solution calorimetry in agreement. • Experimental results evaluated and compared with G4 calculations. - Abstract: Vapor pressures of the isomeric 2-, 3-, and 4-pyridinecarboxamides were measured by using the transpiration method. The enthalpies of sublimation/vaporization of these compounds at 298.15 K were derived from vapor pressure temperature dependences. The enthalpies of solution of the isomeric pyridinecarboxamides were measured with the high-precision solution calorimetry. The enthalpies of sublimation of 3- and 4-pyridinecarboxamides were independently derived with help of the solution calorimetry based procedure. The enthalpies of fusion of the pyridinecarboxamides were measured by the DSC. Thermochemical data isomeric pyridinecarboxamides were collected, evaluated, and tested for internal consistency. The high-level G4 quantum-chemical method was used for mutual validation of the experimental and theoretical gas phase enthalpies of formation successfully.

  11. Influência de alguns parâmetros experimentais nos resultados de análises calorimétricas diferenciais - DSC

    OpenAIRE

    Bernal, Cláudia; Couto, Andréa Boldarini; Breviglieri, Susete Trazzi; Cavalheiro, Éder Tadeu Gomes

    2002-01-01

    A series of experiments were performed in order to demonstrate to undergraduate students or users of the differential scanning calorimetry (DSC), that several factors can influence the qualitative and quantitative aspects of DSC results. Saccharin, an artificial sweetner, was used as a probe and its thermal behavior is also discussed on the basis of thermogravimetric (TG) and DSC curves.

  12. Influência de alguns parâmetros experimentais nos resultados de análises calorimétricas diferenciais - DSC

    Directory of Open Access Journals (Sweden)

    Bernal Cláudia

    2002-01-01

    Full Text Available A series of experiments were performed in order to demonstrate to undergraduate students or users of the differential scanning calorimetry (DSC, that several factors can influence the qualitative and quantitative aspects of DSC results. Saccharin, an artificial sweetner, was used as a probe and its thermal behavior is also discussed on the basis of thermogravimetric (TG and DSC curves.

  13. CFD and Experimental Studies on Wind Turbines in Complex Terrain by Improved Actuator Disk Method

    Science.gov (United States)

    Liu, Xin; Yan, Shu; Mu, Yanfei; Chen, Xinming; Shi, Shaoping

    2017-05-01

    In this paper, an onshore wind farm in mountainous area of southwest China was investigated through numerical and experimental methods. An improved actuator disk method, taking rotor data (i.e. blade geometry information, attack angle, blade pitch angle) into account, was carried out to investigate the flow characteristic of the wind farm, especially the wake developing behind the wind turbines. Comparing to the classic AD method and the situ measurements, the improved AD shows better agreements with the measurements. The turbine power was automatically predicted in CFD by blade element method, which agreed well with the measurement results. The study proved that the steady CFD simulation with improved actuator disk method was able to evaluate wind resource well and give good balance between computing efficiency and accuracy, in contrary to much more expensive computation methods such as actuator-line/actuator-surface transient model, or less accurate methods such as linear velocity reduction wake model.

  14. Thermal stability of the DSC ruthenium dye C106 in robust electrolytes

    DEFF Research Database (Denmark)

    Lund, Torben; Phuong, Nguyen Tuyet; Pechy, Peter

    2014-01-01

    We have investigated the thermal stability of the heteroleptic ruthenium complex C106 employed as a sensitizer in dye-sensitized solar cells. The C106 was adsorbed on TiO2 particles and exposed to 2 different iodide/triidode based redox electrolytes A and B at 80 °C for up to 1500 h in sealed glass......) substitution products 3 and 4 formed by replacement of the thiocyanate ligand by NBB after 1500 h of heating at 80 °C. Samples prepared under ambient conditions gave a steady state C106 concentration of 60% of the initial value and 40% substitution products. The C106 degradation was found to be independent...... of the degree of dye loading of the TiO2 particles and the ratio between the amount of dyed TiO2 particles and electrolyte volume. Assuming that this substitution is the predominant loss mechanism in a DSC during thermal stress, we estimate the reduction in the DSC efficiency after long term heat to be 12...

  15. DSC analyses of static and dynamic precipitation of an Al–Mg–Si–Cu aluminum alloy

    Directory of Open Access Journals (Sweden)

    Manping Liu

    2015-04-01

    Full Text Available In the present investigation, both static and dynamic precipitations of an Al–Mg–Si–Cu aluminum alloy after solid-solution treatment (SST were comparatively analyzed using differential scanning calorimetry (DSC. Dynamic aging was performed in the SST alloy through equal channel angular pressing (ECAP at different temperatures of room temperature, 110, 170, 191 and 300 °C. For comparison, static artificial aging was conducted in the SST alloy at 191 °C with two aging times of 4 and 10 h. The DSC analyses reveal that the dynamic precipitation has occurred in the ECAPed samples, while the activation energies associated with the strengthening precipitates in the dynamic samples are considerably higher than the energies in the SST and static aged samples. The higher activation energies are probably attributed to the smaller grains and higher dislocation density developed after ECAP. The results in the present investigation allow the prediction of the type of the dynamic precipitates to influence the strength of the ultrafine grained alloy during ECAP at various temperatures.

  16. Hydriding properties of amorphous Ni-B alloy studied by DSC and thermogravimetry

    International Nuclear Information System (INIS)

    Spassov, T.; Rangelova, V.

    1999-01-01

    The hydrogenation behaviour of melt-spun Ni 81.5 B 18.5 amorphous alloy was studied by means of differential scanning calorimetry (DSC) and thermogravimetry (TG) and compared with the hydriding properties of a Fe-B-Si glass. It was found that the amorphous Ni-B alloy absorbs larger amounts of hydrogen than the Fe-B-Si glass, as the initial kinetics of hydrogen absorption and desorption of both the alloys are comparable. Hydrogen absorption and desorption reactions in Ni-B were observed to proceed with similar rates at ca. 300 K. The hydrogen desorption is revealed in DSC as an endothermic peak in the 350-450 K range, preceding the crystallization peak of the amorphous alloy. The enthalpy of hydrogen desorption (ΔH des =22 kJ/mol H 2 ) for Ni-B was found to be smaller than that for the Fe-B-Si glass, which finding is in contrast to the results on hydrogen diffusion in crystalline αFe and Fe-based alloys and Ni and Ni-based alloys. The hydrogen desorption temperature and enthalpy for Ni 81.5 B 18.5 were found to be independent of the amount of hydrogen absorbed. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  17. Investigation of sol-gel transition by rheological methods. Part I. Experimental methods.

    Directory of Open Access Journals (Sweden)

    KUDRYAVTSEV Pavel Gennadievich

    2017-08-01

    Full Text Available In this work rheological studies of the gelling process were carried out. We have developed a measuring system for studying the rheology of the gelation process. It consisted of several measuring cells of the Weiler-Rebinder type, system for automatic regulation of the composition of the medium and hermostabilization system. This complex is designed to measure the dependence of the value of the ultimate shear stress as a function of time, from the start of the sol-gel transition to the complete conversion of the sol to the gel. The developed device has a wide range of measured values of critical shear stresses τ0 = (0,05÷50000 Dyne/cm2. Using the developed instrument, it was possible to establish the shape of the initial section of the curve τ0 = f(t and develop a methodology for more accurate determination of gelation time. The developed method proved that the classical method for determining the start time of the sol-gel transition using the point of intersection of the tangent to the linear part of the rheological curve τ0 = f(t,gives significantly distorted results. A new phenomenon has been discovered: the kinetic curves in the coordinates of the Avrami-Erofeev-Bogolyubov equation have an inflection point which separates the kinetic curve into two parts, the initial and the final. It was found that the constant k in the Avrami–Erofeev–Bogolyubov quation does not depend on the temperature and is the same for both the initial and final parts of the kinetic curve. It depends only on the chemical nature of the reacting system. It was found that for the initial section of the kinetic curves, the value of the parameter n in the Avrami-Erofeev-Bogolyubov equation was n = 23,4±2,8 and, unlike the final section of the rheological curve, does not depend on temperature. A large value of this parameter can be interpreted as the average number of directions of growth of a fractal aggregate during its growth. The value of this parameter depends

  18. Disorder Prediction Methods, Their Applicability to Different Protein Targets and Their Usefulness for Guiding Experimental Studies

    Directory of Open Access Journals (Sweden)

    Jennifer D. Atkins

    2015-08-01

    Full Text Available The role and function of a given protein is dependent on its structure. In recent years, however, numerous studies have highlighted the importance of unstructured, or disordered regions in governing a protein’s function. Disordered proteins have been found to play important roles in pivotal cellular functions, such as DNA binding and signalling cascades. Studying proteins with extended disordered regions is often problematic as they can be challenging to express, purify and crystallise. This means that interpretable experimental data on protein disorder is hard to generate. As a result, predictive computational tools have been developed with the aim of predicting the level and location of disorder within a protein. Currently, over 60 prediction servers exist, utilizing different methods for classifying disorder and different training sets. Here we review several good performing, publicly available prediction methods, comparing their application and discussing how disorder prediction servers can be used to aid the experimental solution of protein structure. The use of disorder prediction methods allows us to adopt a more targeted approach to experimental studies by accurately identifying the boundaries of ordered protein domains so that they may be investigated separately, thereby increasing the likelihood of their successful experimental solution.

  19. Experimental verification of neutron emission method for measuring of fissile material content in spent fuel

    International Nuclear Information System (INIS)

    Abou-Zaid, A.A.; Pytel, K.

    1999-01-01

    A non-destructive method of measurement of fissile nuclides content remained in spent fuel from research reactor is presented. The method, called the neutron emission one, is based on counting of fission neutrons emitted from fissile isotopes: 235 U, 239 Pu, 241 Pu. Fissions are induced mainly by neutrons supplied by the external neutron source. Another effects contribute also to the measured neutron population, e. g. source neutrons from penetrating the fuel without being captured and scattered, neutrons (α,n) reactions and from spontaneous fissions of actinides. Complexity of phenomena occurring within the measurement facility required the detailed numerical simulation and experimental studies prior design of ultimate measurement stand. In the previous paper, the results of Monte Carlo simulation on optimisation of measuring stand for neutron emission method were presented. On the basis of those results, the experimental stand for Maria reactor fuel investigation has been designed and manufactured. The present paper, being the continuation of previous one, contains the description of experimental facility and the results of measurements for the fresh fuel (without burnup) and the fuel mock-up (without fissile materials). Although some discrepancies were found between Monte Carlo and experimental results, the main conclusions concerning the optimal geometry of measuring facility have been confirmed. (author)

  20. Experimental Method for Characterizing Electrical Steel Sheets in the Normal Direction

    Directory of Open Access Journals (Sweden)

    Thierry Belgrand

    2010-10-01

    Full Text Available This paper proposes an experimental method to characterise magnetic laminations in the direction normal to the sheet plane. The principle, which is based on a static excitation to avoid planar eddy currents, is explained and specific test benches are proposed. Measurements of the flux density are made with a sensor moving in and out of an air-gap. A simple analytical model is derived in order to determine the permeability in the normal direction. The experimental results for grain oriented steel sheets are presented and a comparison is provided with values obtained from literature.

  1. An experimental-numerical method for comparative analysis of joint prosthesis

    International Nuclear Information System (INIS)

    Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

    2001-01-01

    The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs

  2. Physical principles underlying the experimental methods for studying the orientational order of liquid crystals

    International Nuclear Information System (INIS)

    Limmer, S.

    1989-01-01

    The basic physical principles underlying different experimental methods frequently used for the determination of orientational order parameters of liquid crystals are reviewed. The methods that are dealt with here include the anisotropy of the diamagnetic susceptibility, birefringence, linear dichroism, Raman scattering, fluorescence depolarization, electron paramagnetic resonance (EPR), and nuclear magnetic resonance (NMR). The fundamental assertions that can be obtained by the different methods as well as their advantages, drawbacks and limitations are inspected. Typical sources of uncertainties and inaccuracies are discussed. To quantitatively evaluate the experimental data with reference to the orientational order the general tensor formalism developed by Schmiedel was employed throughout according to which the order matrix comprises 25 real elements yet. Within this context the interplay of orientational ordering and molecular conformation is scrutinized. (author)

  3. Influence of different methods of internal bone fixation on characteristics of bone callus in experimental animals

    Directory of Open Access Journals (Sweden)

    Gajdobranski Đorđe

    2014-01-01

    Full Text Available Introduction. Correct choice of osteosynthesis method is a very important factor in providing the optimal conditions for appropriate healing of the fracture. There are still disagreements about the method of stabilization of some long bone fractures. Critically observed, no method of fracture fixation is ideal. Each osteosynthesis method has both advantages and weaknesses. Objective. The objective of this study was to compare the results of the experimental application of three different internal fixation methods: plate fixation, intramedullary nail fixation and self-dynamisable internal fixator (SIF. Methods. A series of 30 animals were used (Lepus cuniculus as experimental animals, divided into three groups of ten animals each. Femoral diaphysis of each animal was osteotomized and fixed with one of three implants. Ten weeks later all animals were sacrificed and each specimen underwent histological and biomechanical testing. Results. Histology showed that the healing process with SIF was more complete and bone callus was more mature in comparison to other two methods. During biomechanical investigation (computerized bending stress test, it was documented with high statistical significance that using SIF led to stronger healing ten weeks after the operation. Conclusion. According to the results obtained in this study, it can be concluded that SIF is a suitable method for fracture treatment.

  4. Discussion of the experimental methods of the estimation of the reaction impact parameter

    International Nuclear Information System (INIS)

    Muryn, B.; Dziunikowska, K.; Eskreys, A.; Coghen, T.

    1978-01-01

    Two methods of determination of the reaction impact parameter, the one proposed by Webber and other by Henyey and Pumplin, are compared and discussed. It is shown that the lower limits of the impact parameter bsub(L) obtained by means of these methods are comparable and are always very low (approximately < 0.5 fm). On the example of the Henyey - Pumplin method it is argued that the experimentally obtained values bsub(L) may be very unreliable estimates of the reaction impact parameter and that any comparison of different reactions or reactions channels may be meaningless. (author)

  5. Method for calculating thermal properties of lightweight floor heating panels based on an experimental setup

    DEFF Research Database (Denmark)

    Weitzmann, Peter; Svendsen, Svend

    2005-01-01

    , radiation and conduction of the heat transfer between pipe and surrounding materials. The European Standard for floor heating, EN1264, does not cover lightweight systems, while the supplemental Nordtest Method VVS127 is aimed at lightweight systems. The thermal properties can be found using tabulated values...... simulation model. It has been shown that the method is accurate with an error on the heat fluxes of less than 5% for different supply temperatures. An error of around 5% is also recorded when comparing measurements to calculated heat flows using the Nordtest VVS 127 method based on the experimental setup...

  6. Experimental validation of the buildings energy performance (PEC assessment methods with reference to occupied spaces heating

    Directory of Open Access Journals (Sweden)

    Cristian PETCU

    2010-01-01

    Full Text Available This paper is part of the series of pre-standardization research aimed to analyze the existing methods of calculating the Buildings Energy Performance (PEC in view of their correction of completing. The entire research activity aims to experimentally validate the PEC Calculation Algorithm as well as the comparative application, on the support of several case studies focused on representative buildings of the stock of buildings in Romania, of the PEC calculation methodology for buildings equipped with occupied spaces heating systems. The targets of the report are the experimental testing of the calculation models so far known (NP 048-2000, Mc 001-2006, SR EN 13790:2009, on the support provided by the CE INCERC Bucharest experimental building, together with the complex calculation algorithms specific to the dynamic modeling, for the evaluation of the occupied spaces heat demand in the cold season, specific to the traditional buildings and to modern buildings equipped with solar radiation passive systems, of the ventilated solar space type. The schedule of the measurements performed in the 2008-2009 cold season is presented as well as the primary processing of the measured data and the experimental validation of the heat demand monthly calculation methods, on the support of CE INCERC Bucharest. The calculation error per heating season (153 days of measurements between the measured heat demand and the calculated one was of 0.61%, an exceptional value confirming the phenomenological nature of the INCERC method, NP 048-2006. The mathematical model specific to the hourly thermal balance is recurrent – decisional with alternating paces. The experimental validation of the theoretical model is based on the measurements performed on the CE INCERC Bucharest building, within a time lag of 57 days (06.01-04.03.2009. The measurements performed on the CE INCERC Bucharest building confirm the accuracy of the hourly calculation model by comparison to the values

  7. Shape sensing methods: Review and experimental comparison on a wing-shaped plate

    Science.gov (United States)

    Gherlone, Marco; Cerracchio, Priscilla; Mattone, Massimiliano

    2018-05-01

    Shape sensing, i.e., the reconstruction of the displacement field of a structure from some discrete surface strain measurements, is a fundamental capability for the structural health management of critical components. In this paper, a review of the shape sensing methodologies available in the open literature and of the different applications is provided. Then, for the first time, an experimental comparative study is presented among the main approaches in order to highlight their relative merits in presence of uncertainties affecting real applications. These approaches are, namely, the inverse Finite Element Method, the Modal Method and Ko's Displacement Theory. A brief description of these methods is followed by the presentation of the experimental test results. A cantilevered, wing-shaped aluminum plate is let deform under its own weight, leading to bending and twisting. Using the experimental strain measurements as input data, the deflection field of the plate is reconstructed using the three aforementioned approaches and compared with the actual measured deflection. The inverse Finite Element Method is proven to be slightly more accurate and particularly attractive because it is versatile with respect to the boundary conditions and it does not require any information about material properties and loading conditions.

  8. Thermo-kinetic prediction of metastable and stable phase precipitation in Al–Zn–Mg series aluminium alloys during non-isothermal DSC analysis

    International Nuclear Information System (INIS)

    Lang, Peter; Wojcik, Tomasz; Povoden-Karadeniz, Erwin; Falahati, Ahmad; Kozeschnik, Ernst

    2014-01-01

    Highlights: • Comparison of laboratory Al–Zn–Mg alloy to industrial Al 7xxx series. • Heat flow evolution during non-isothermal DSC analysis is calculated. • TEM investigations of laboratory Al–Zn–Mg alloy at three pronounced temperatures. • Simulation and modelling of precipitation sequence. • Calculation and prediction of heat flow curves of Al 7xxx series. - Abstract: The technological properties of heat treatable Al–Zn–Mg alloys originate in the morphology and distribution of metastable particles. Starting from the solution-annealed condition, this paper describes the precipitate evolution during non-isothermal temperature changes, namely continuous heating differential scanning calorimetry (DSC) analysis. The distribution and the morphology of the metastable and stable precipitates and the heat flow accompanying the precipitation process is investigated experimentally and calculated by numerical thermo-kinetic simulations. The computer simulation results of the sizes and distributions are confirmed by transmission electron microscopy (TEM). The theoretical background and the results of the investigations are discussed

  9. Thermo-kinetic prediction of metastable and stable phase precipitation in Al–Zn–Mg series aluminium alloys during non-isothermal DSC analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lang, Peter, E-mail: pl404@cam.ac.uk [Department of Materials Science and Metallurgy, University of Cambridge, Charles Babbage Road 27, Cambridge CB3 0FS (United Kingdom); Wojcik, Tomasz [Institute of Materials Science and Technology, Vienna University of Technology, Favoritenstraße 9-11, Vienna 1040 (Austria); Povoden-Karadeniz, Erwin [Institute of Materials Science and Technology, Vienna University of Technology, Favoritenstraße 9-11, Vienna 1040 (Austria); Christian Doppler Laboratory “Early Stages of Precipitation”, Institute of Materials Science and Technology, Vienna University of Technology, Favoritenstraße 9-11, Vienna 1040 (Austria); Falahati, Ahmad [Institute of Materials Science and Technology, Vienna University of Technology, Favoritenstraße 9-11, Vienna 1040 (Austria); Kozeschnik, Ernst [Institute of Materials Science and Technology, Vienna University of Technology, Favoritenstraße 9-11, Vienna 1040 (Austria); Christian Doppler Laboratory “Early Stages of Precipitation”, Institute of Materials Science and Technology, Vienna University of Technology, Favoritenstraße 9-11, Vienna 1040 (Austria)

    2014-10-01

    Highlights: • Comparison of laboratory Al–Zn–Mg alloy to industrial Al 7xxx series. • Heat flow evolution during non-isothermal DSC analysis is calculated. • TEM investigations of laboratory Al–Zn–Mg alloy at three pronounced temperatures. • Simulation and modelling of precipitation sequence. • Calculation and prediction of heat flow curves of Al 7xxx series. - Abstract: The technological properties of heat treatable Al–Zn–Mg alloys originate in the morphology and distribution of metastable particles. Starting from the solution-annealed condition, this paper describes the precipitate evolution during non-isothermal temperature changes, namely continuous heating differential scanning calorimetry (DSC) analysis. The distribution and the morphology of the metastable and stable precipitates and the heat flow accompanying the precipitation process is investigated experimentally and calculated by numerical thermo-kinetic simulations. The computer simulation results of the sizes and distributions are confirmed by transmission electron microscopy (TEM). The theoretical background and the results of the investigations are discussed.

  10. Experimental study on reactivity measurement in thermal reactor by polarity correlation method

    International Nuclear Information System (INIS)

    Yasuda, Hideshi

    1977-11-01

    Experimental study on the polarity correlation method for measuring the reactivity of a thermal reactor, especially the one possessing long prompt neutron lifetime such as graphite on heavy water moderated core, is reported. The techniques of reactor kinetics experiment are briefly reviewed, which are classified in two groups, one characterized by artificial disturbance to a reactor and the other by natural fluctuation inherent in a reactor. The fluctuation phenomena of neutron count rate are explained using F. de Hoffman's stochastic method, and correlation functions for the neutron count rate fluctuation are shown. The experimental results by polarity correlation method applied to the β/l measurements in both graphite-moderated SHE core and light water-moderated JMTRC and JRR-4 cores, and also to the measurement of SHE shut down reactivity margin are presented. The measured values were in good agreement with those by a pulsed neutron method in the reactivity range from critical to -12 dollars. The conditional polarity correlation experiments in SHE at -20 cent and -100 cent are demonstrated. The prompt neutron decay constants agreed with those obtained by the polarity correlation experiments. The results of experiments measuring large negative reactivity of -52 dollars of SHE by pulsed neutron, rod drop and source multiplication methods are given. Also it is concluded that the polarity and conditional polarity correlation methods are sufficiently applicable to noise analysis of a low power thermal reactor with long prompt neutron lifetime. (Nakai, Y.)

  11. An Experimental Test of a Biodynamic Method of Weed Suppression: The Biodynamic Seed Peppers

    Directory of Open Access Journals (Sweden)

    Bruce Kenneth Kirchoff

    2016-04-01

    Full Text Available An experimental test of a biodynamic agriculture method of weed suppression was carried out in growth chambers to establish the feasibility of the method as a preliminary to field trials. Four generations of Brassica rapa plants were used in a randomized block design. Treated flats received ashed seeds prepared according to biodynamic indications. Seed weight and counts were measured at the end of each generation, and germination of the control and experimental seed was investigated at the end of generation four. The biodynamic seed peppers, created and applied as described here, had no effect on seed production or viability, and did not effectively inhibit reproduction of the targeted species over the course of four consecutive treatments.

  12. Numerical and experimental validation of a particle Galerkin method for metal grinding simulation

    Science.gov (United States)

    Wu, C. T.; Bui, Tinh Quoc; Wu, Youcai; Luo, Tzui-Liang; Wang, Morris; Liao, Chien-Chih; Chen, Pei-Yin; Lai, Yu-Sheng

    2018-03-01

    In this paper, a numerical approach with an experimental validation is introduced for modelling high-speed metal grinding processes in 6061-T6 aluminum alloys. The derivation of the present numerical method starts with an establishment of a stabilized particle Galerkin approximation. A non-residual penalty term from strain smoothing is introduced as a means of stabilizing the particle Galerkin method. Additionally, second-order strain gradients are introduced to the penalized functional for the regularization of damage-induced strain localization problem. To handle the severe deformation in metal grinding simulation, an adaptive anisotropic Lagrangian kernel is employed. Finally, the formulation incorporates a bond-based failure criterion to bypass the prospective spurious damage growth issues in material failure and cutting debris simulation. A three-dimensional metal grinding problem is analyzed and compared with the experimental results to demonstrate the effectiveness and accuracy of the proposed numerical approach.

  13. CO2 Capture in Ionic Liquids: A Review of Solubilities and Experimental Methods

    Directory of Open Access Journals (Sweden)

    Elena Torralba-Calleja

    2013-01-01

    Full Text Available The growing concern of climate change and global warming has in turn given rise to a thriving research field dedicated to finding solutions. One particular area which has received considerable attention is the lowering of carbon dioxide emissions from large-scale sources, that is, fossil fuel power. This paper focuses on ionic liquids being used as novel media for CO2 capture. In particular, solubility data and experimental techniques are used at a laboratory scale. Cited CO2 absorption data for imidazolium-, pyrrolidinium-, pyridinium-, quaternary-ammonium-, and tetra-alkyl-phosphonium-based ionic liquids is reviewed, expressed as mole fractions (X of CO2 to ionic liquid. The following experimental techniques are featured: gravimetric analysis, the pressure drop method, and the view-cell method.

  14. An Experimental Comparison of Two Methods on Photosynthesis Driving Soil Respiration: Girdling and Defoliation.

    Science.gov (United States)

    Jing, Yanli; Guan, Dexin; Wu, Jiabing; Wang, Anzhi; Jin, Changjie; Yuan, Fenghui

    2015-01-01

    Previous studies with different experimental methods have demonstrated that photosynthesis significantly influences soil respiration (RS). To compare the experimental results of different methods, RS after girdling and defoliation was measured in five-year-old seedlings of Fraxinus mandshurica from June to September. Girdling and defoliation significantly reduced RS by 33% and 25% within 4 days, and 40% and 32% within the entire treatment period, respectively. The differential response of RS to girdling and defoliation was a result of the over-compensation for RS after girdling and redistribution of stored carbon after defoliation. No significant effect on RS was observed between girdling and defoliation treatment, while the soluble sugar content in fine roots was higher in defoliation than in girdling treatment, indicating that defoliation had less compensation effect for RS after interrupting photosynthates supply. We confirm the close coupling of RS with photosynthesis and recommend defoliation for further studies to estimate the effect of photosynthesis on RS.

  15. A systematic study of distribution characters of infiltration parameters in an experimental basin by nuclear methods

    International Nuclear Information System (INIS)

    Gu Weizu; Lu Jieju; Lu Mingjiang; Chen Tingyang

    1988-01-01

    A case study of spatial variability of Philip's infiltration parameters was carried out in a small experimental catchment with an area of 0.8 ha by nuclear monitoring methods. Relationships between sorptivity S, parameter A and the average initial soil water content within 0.5 m depth of soil profiles over the catchment have been plotted. A watershed infiltration parameter distribution curve is set up and fitted approximately by f/F=1-(1-S/S M ) n . The parameters of composite infiltration response related to whole catchment are suggested. The author has studied it on an experimental basin by combined method of nuclear technology and micro-geomorphic analysis. The results are satisfactory. (author). 6 refs, 11 figs, 2 tabs

  16. 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.

  17. The Experimental Study of the Inductive Heating Process by the cleating Method

    Directory of Open Access Journals (Sweden)

    Dorel Anton HOBLE

    2009-05-01

    Full Text Available The paper focuses on onemethod of welding of two coaxial cylinders, made ofdifferent materials. The method of welding usesinductive heating technology, and it is based on thedifferent dilatation coefficient of the materials, theinside material has an upper value of the dilatationcoefficient. In the paper it was analyzed the inducedpower density inside the ferromagnetic material, andthe distribution of the temperature field inside thestructure. The theoretical results were utilized tomake an experimental model.

  18. Estimation of the drift eliminator efficiency using numerical and experimental methods

    Directory of Open Access Journals (Sweden)

    Stodůlka Jiří

    2016-01-01

    Full Text Available The purpose of the drift eliminators is to prevent water from escaping in significant amounts the cooling tower. They are designed to catch the droplets dragged by the tower draft and the efficiency given by the shape of the eliminator is the main evaluation criteria. The ability to eliminate the escaping water droplets is studied using CFD and using the experimental IPI method.

  19. Experimental Study of WBFC method for testing electromagnetic immunity of integrated circuits

    OpenAIRE

    香川, 直己; カガワ, ナオキ; Naoki, KAGAWA

    2004-01-01

    The author made a workbench faraday cage, WBFC, in order to estimate performance of the WBFC method for the measurement of common mode noise immunity of integrated circuits. In this report, characteristics of the constructed workbench faraday cage and results of experimental study of effects of the common mode noise on a circuit board including an electronic device are shown. Selected DUT, LM324 is popular operational amplifier for electrical circuits in vehicles.

  20. Comparison of first pass bolus AIFs extracted from sequential 18F-FDG PET and DSC-MRI of mice

    International Nuclear Information System (INIS)

    Evans, Eleanor; Sawiak, Stephen J.; Ward, Alexander O.; Buonincontri, Guido; Hawkes, Robert C.; Adrian Carpenter, T.

    2014-01-01

    Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and 18 F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies

  1. Synthesis, characterization and TG-DSC study of cadmium halides adducts with caffeine

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Robson F. de; Silva, Ademir O. da; Silva, Umberto G. da

    2003-11-28

    The synthesis, characterization and TG-DSC study of the compounds CdX{sub 2}{center_dot}ncaff, for which X: Cl, Br and I; n=1 and 2 and caff: caffeine is reported. It is verified that caffeine is coordinated through more than one coordination site, despite the fact that the nitrogen of the imidazole ring is the main coordination site. The following thermal stability trend is observed: Cl>Br>I and monoadducts are more stable than bisadducts. The thermal degradation (td) enthalpies have the values (kJ mol{sup -1}): 58.2 and 71.5; 74.9 and 91.4; 31.1 and 47.5 for Cl, Br and I mono and bisadducts, respectively.

  2. Evaluation of the interaction of surfactants with stratum corneum model membrane from Bothrops jararaca by DSC.

    Science.gov (United States)

    Baby, André Rolim; Lacerda, Aurea Cristina Lemos; Velasco, Maria Valéria Robles; Lopes, Patrícia Santos; Kawano, Yoshio; Kaneko, Telma Mary

    2006-07-06

    The interaction of surfactants sodium dodecyl sulfate (SDS), cetyl trimethyl ammonium chloride (CTAC) and lauryl alcohol ethoxylated (12 mol ethylene oxide) (LAE-12OE) was evaluated on the stratum corneum (SC) of shed snake skins from Bothrops jararaca, used as model membrane, and thermal characterized by differential scanning calorimetry (DSC). Surfactant solutions were employed above of the critical micellar concentration (CMC) with treatment time of 8h. The SDS interaction with the SC model membrane has increased the characteristic transition temperature of 130 degrees C in approximately 10 degrees C for the water loss and keratin denaturation, indicating an augmentation of the water content. Samples treated with CTAC have a decrease of the water loss temperature, while, for the LAE-12OE treated samples, changes on the transition temperature have not been observed.

  3. Complex Heat Capacity of Lithium Borate Glasses Studied by Modulated DSC

    Science.gov (United States)

    Matsuda, Yu; Matsui, Chihiro; Ike, Yuji; Kodama, Masao; Kojima, Seiji

    2006-05-01

    Complex heat capacity, Cp* = Cp' - iCp″, of lithium borate glasses Li2Oṡ(1-x)B2O3 (x = 0.00 - 0.33) has been investigated by Modulated DSC (MDSC). We have successfully observed the frequency dependent Cp* by MDSC in the frequency range 0.01 to 0.1 Hz, and the average relaxation time of glass transition has been determined as a function of temperature. Moreover, the composition dependence of the thermal properties has been investigated. The calorimetric glass transition temperatures become higher with the increase of concentration of Li2O and show the board maximum around x = 0.26-0.28. The width of glass transition region becomes narrower as Li2O increases. These results relate to the change of the fragility of the system. It has been proven that the complex heat capacity spectroscopy by MDSC is a powerful tool to investigate the glass transition phenomena.

  4. Calculated and experimental substantiation of the thermal method for non-destructive testing of fuel elements

    International Nuclear Information System (INIS)

    Maksimov, N.M.; Soldatenko, V.A.; Petrovichev, V.I.; Salimov, S.E.; Aleksandrov, K.A.; Kurov, D.A.

    1985-01-01

    The main systems and methods of thermal testing, their potentialities and advantages, thermal irradiation photodetectors are described. Possible fields of application of thermal testing in nuclear engineering are discussed. Calculations of the fuel element nonstationary temperature field in the three-dimensional geometry in the presence of such an effect as fuel exfaliation from cladding are presented. The developed method and equipment for fuel element thermal testing are described. Preliminary experimental data being in agreement with the calculated ones and opening the prospects for flaw detecting are presened

  5. Method of Increasing Identification Accuracy under Experimental Tests of Dynamic Objects

    Directory of Open Access Journals (Sweden)

    Y. N. Pavlov

    2015-01-01

    Full Text Available The work concerns a problem of increasing identification accuracy of linear dynamic systems on the basis of experimental data obtained by applying test signals to the system.The work is aimed at considering a possibility to use the experimentally obtained hodograph counting to determine parameters of this system in a specific context of the linear dynamic system of the second order.An offer was to use a method of harmonious linearization and a described cut method.The type of frequency transfer function of the identified system was assumed as known.It was supposed that when obtaining the frequency characteristics of a real system there are disturbances interfering with experiment as a result of which points of experimentally received hodograph are random displaced.An identification problem solution was searched in a class of the hodograph set by the system model, which had the same type of frequency transfer function, as the type of frequency transfer function of the identified system.The unknown coefficients of frequency transfer function of the system model were searched through minimizing a proximity criterion (measure of the experimentally received hodograph of the system and of the system model hodograph over the entire aggregate of points. One of the authors described this criterion in the earlier publication.The solution to a problem of nonlinear dynamic system identification by the frequency hodograph was reduced to the solution of the system of equations of the rather unknown linear parameters of frequency transfer function of the system model.The program to simulate a process of the pseudo-experimental data, containing random errors, and determine parameters of this system is developed for a dynamic system of the second order.A conducted computing experiment is conducted to estimate an error at which the offered algorithm defines the values of parameters of this system.

  6. A composite experimental dynamic substructuring method based on partitioned algorithms and localized Lagrange multipliers

    Science.gov (United States)

    Abbiati, Giuseppe; La Salandra, Vincenzo; Bursi, Oreste S.; Caracoglia, Luca

    2018-02-01

    Successful online hybrid (numerical/physical) dynamic substructuring simulations have shown their potential in enabling realistic dynamic analysis of almost any type of non-linear structural system (e.g., an as-built/isolated viaduct, a petrochemical piping system subjected to non-stationary seismic loading, etc.). Moreover, owing to faster and more accurate testing equipment, a number of different offline experimental substructuring methods, operating both in time (e.g. the impulse-based substructuring) and frequency domains (i.e. the Lagrange multiplier frequency-based substructuring), have been employed in mechanical engineering to examine dynamic substructure coupling. Numerous studies have dealt with the above-mentioned methods and with consequent uncertainty propagation issues, either associated with experimental errors or modelling assumptions. Nonetheless, a limited number of publications have systematically cross-examined the performance of the various Experimental Dynamic Substructuring (EDS) methods and the possibility of their exploitation in a complementary way to expedite a hybrid experiment/numerical simulation. From this perspective, this paper performs a comparative uncertainty propagation analysis of three EDS algorithms for coupling physical and numerical subdomains with a dual assembly approach based on localized Lagrange multipliers. The main results and comparisons are based on a series of Monte Carlo simulations carried out on a five-DoF linear/non-linear chain-like systems that include typical aleatoric uncertainties emerging from measurement errors and excitation loads. In addition, we propose a new Composite-EDS (C-EDS) method to fuse both online and offline algorithms into a unique simulator. Capitalizing from the results of a more complex case study composed of a coupled isolated tank-piping system, we provide a feasible way to employ the C-EDS method when nonlinearities and multi-point constraints are present in the emulated system.

  7. DSC, X-ray and FTIR studies of a gemfibrozil/dimethyl-β-cyclodextrin inclusion complex produced by co-grinding.

    Science.gov (United States)

    Aigner, Z; Berkesi, O; Farkas, G; Szabó-Révész, P

    2012-01-05

    The steps of formation of an inclusion complex produced by the co-grinding of gemfibrozil and dimethyl-β-cyclodextrin were investigated by differential scanning calorimetry (DSC), X-ray powder diffractometry (XRPD) and Fourier transform infrared (FTIR) spectroscopy with curve-fitting analysis. The endothermic peak at 59.25°C reflecting the melting of gemfibrozil progressively disappeared from the DSC curves of the products on increase of the duration of co-grinding. The crystallinity of the samples too gradually decreased, and after 35min of co-grinding the product was totally amorphous. Up to this co-grinding time, XRPD and FTIR investigations indicated a linear correlation between the cyclodextrin complexation and the co-grinding time. After co-grinding for 30min, the ratio of complex formation did not increase. These studies demonstrated that co-grinding is a suitable method for the complexation of gemfibrozil with dimethyl-β-cyclodextrin. XRPD analysis revealed the amorphous state of the gemfibrozil-dimethyl-β-cyclodextrin product. FTIR spectroscopy with curve-fitting analysis may be useful as a semiquantitative analytical method for discriminating the molecular and amorphous states of gemfibrozil. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Overview of experimental progress on understanding photon strength functions with an emphasis of the Oslo method

    Science.gov (United States)

    Krticka, Milan

    2015-10-01

    The so-called Photon Strength Functions (PSFs) for different multipolarities are, together with the Nuclear Level Density (NLD) the key entities describing the statistical γ-decay of nucleus. It is well known that PSFs at energies above the threshold for particle emission are well described by the Lorentzian shape of the Giant Electric Dipole Resonance (GEDR). On the other hand, shapes of RSFs at the low-energy tail of GEDR are known rather poorly. Information on the PSFs at the GEDR tail can be obtained from several different experimental techniques. They will be summarized and the most important ones briefly introduced in this contribution. Special emphasis will be put on the so-called Oslo method which allows simultaneous extraction of the NLD and the PSFs from particle- γ coincidence measurements. This method has been used for determining the NLD and the PSFs in many nuclei in A ~ 45- 240 range during past years. Examples of the most interesting results obtained with this method will be shown. The results will be compared to information on the PSFs available from other experimental techniques. The strengths and the weaknesses of the method will be thoroughly discussed.

  9. Experimental verification on limit load estimation method for pipes with an arbitrary shaped circumferential surface flaw

    International Nuclear Information System (INIS)

    Li, Yinsheng; Hasegawa, Kunio; Miura, Naoki; Hoshino, Katsuaki

    2010-01-01

    When a flaw is detected in stainless steel pipes during in-service inspection, the limit load criterion given in the codes such as JSME Rules on Fitness-for-Service for Nuclear Power Plants or ASME Boiler and Pressure Vessel Code Section XI can be applied to evaluate the integrity of the pipe. However, in these codes, the limit load criterion is only provided for pipes containing a flaw with uniform depth, although many flaws with complicated shape such as stress corrosion cracking have been actually detected in pipes. In order to evaluate the integrity of the flawed pipes for general case, a limit load estimation method has been proposed by authors considering a circumferential surface flaw with arbitrary shape. The plastic collapse bending moment and corresponding stress are obtained by dividing the surface flaw into several segmented sub-flaws. In this paper, the proposed method was verified by comparing with experimental results. Four-point bending experiments were carried out for full scale stainless steel pipes with a symmetrical or non-symmetrical circumferential flaw. Estimated failure bending moments by the proposed method were found to be in good agreement with the experimental results, and the proposed method was confirmed to be effective for evaluating bending failure of pipes with flaw. (author)

  10. X-ray and DSC studies on the melt-recrystallization process of poly(butylene naphthalate)

    International Nuclear Information System (INIS)

    Yasuniwa, Munehisa; Tsubakihara, Shinsuke; Fujioka, Takashi

    2003-01-01

    Melt-recrystallization in the heating process of poly(butylene naphthalate) (PBN) was studied with X-ray analysis and differential scanning calorimetry (DSC). DSC melting curve of an isothermally crystallized sample showed double endothermic peaks. With increasing the temperature, wide-angle X-ray diffraction (WAXD) patterns of the sample were obtained successively. Crystal structure did not change during the double melting process. The X-ray diffraction intensity decreased gradually in the temperature region up to about 200 deg. C, and then increased distinctly before steep decrease due to the final melting. This increase is interpreted as a proof of recrystallization. The temperature derivative curve of the diffraction intensity was similar to the DSC melting curve

  11. Experimental methods and transport models for drug delivery across the blood-brain barrier.

    Science.gov (United States)

    Fu, Bingmei M

    2012-06-01

    The blood-brain barrier (BBB) is a dynamic barrier essential for maintaining the micro-environment of the brain. Although the special anatomical features of the BBB determine its protective role for the central nervous system (CNS) from blood-born neurotoxins, however, the BBB extremely limits the therapeutic efficacy of drugs into the CNS, which greatly hinders the treatment of major brain diseases. This review summarized the unique structures of the BBB, described a variety of in vivo and in vitro experimental methods for determining the transport properties of the BBB, e.g., the permeability of the BBB to water, ions, and solutes including nutrients, therapeutic agents and drug carriers, and presented newly developed mathematical models which quantitatively correlate the anatomical structures of the BBB with its barrier functions. Finally, on the basis of the experimental observations and the quantitative models, several strategies for drug delivery through the BBB were proposed.

  12. Optimization Method of a Low Cost, High Performance Ceramic Proppant by Orthogonal Experimental Design

    Science.gov (United States)

    Zhou, Y.; Tian, Y. M.; Wang, K. Y.; Li, G.; Zou, X. W.; Chai, Y. S.

    2017-09-01

    This study focused on optimization method of a ceramic proppant material with both low cost and high performance that met the requirements of Chinese Petroleum and Gas Industry Standard (SY/T 5108-2006). The orthogonal experimental design of L9(34) was employed to study the significance sequence of three factors, including weight ratio of white clay to bauxite, dolomite content and sintering temperature. For the crush resistance, both the range analysis and variance analysis reflected the optimally experimental condition was weight ratio of white clay to bauxite=3/7, dolomite content=3 wt.%, temperature=1350°C. For the bulk density, the most important factor was the sintering temperature, followed by the dolomite content, and then the ratio of white clay to bauxite.

  13. Evaluation of a Consistent LES/PDF Method Using a Series of Experimental Spray Flames

    Science.gov (United States)

    Heye, Colin; Raman, Venkat

    2012-11-01

    A consistent method for the evolution of the joint-scalar probability density function (PDF) transport equation is proposed for application to large eddy simulation (LES) of turbulent reacting flows containing evaporating spray droplets. PDF transport equations provide the benefit of including the chemical source term in closed form, however, additional terms describing LES subfilter mixing must be modeled. The recent availability of detailed experimental measurements provide model validation data for a wide range of evaporation rates and combustion regimes, as is well-known to occur in spray flames. In this work, the experimental data will used to investigate the impact of droplet mass loading and evaporation rates on the subfilter scalar PDF shape in comparison with conventional flamelet models. In addition, existing model term closures in the PDF transport equations are evaluated with a focus on their validity in the presence of regime changes.

  14. Experimental tests and calculation methods for missile crashing effects on a reactor containment

    International Nuclear Information System (INIS)

    Goldstein, S.; Berriaud, C.; Labrot, R.

    1975-01-01

    In the analysis of missile crashing on a reactor containment there are two main effects to be taken into account: the overall behaviour of the building; the local perforation. The overall behaviour of the building is easily calculated when the applied force as a function of time is known. Two calculation examples are presented. The local perforation is a much more difficult problem and experimental work is necessary. The report presents a series of perforation tests of concrete plates by cylindrical missiles with a flat nose. The aim of these tests is to extrapolate for the lower speeds the existing experimental correlations and to check the calculation methods. The calculations are made with the PASTEL code (Finite elements, implicit integration), with elastoplasticity of the reinforcing steel bars and the concrete. Various plastification and fracturation laws are tested. (Auth.)

  15. Experimental tests and calculation methods for missile crashing effects on a reactor containment

    International Nuclear Information System (INIS)

    Goldstein, S.; Berriaud, C.

    1975-01-01

    In the analysis of missile crashing on a reactor containment there are two main effects to be taken into account: the overall behavior of the building; the local perforation. The overall behavior of the building is easily calculated when the applied force as a function of time is known. Two calculation examples are presented. The local perforation is a much more difficult problem and experimental work is necessary. The report presents a series of perforation tests of concrete plates by cylindrical missiles with a flat nose. The aim of these tests is to extrapolate for the lower speeds the existing experimental correlations (Petry, HN-NDRC, BRL...) and to check the calculation methods. The calculations are made with the PASTEL Code (Finite elements, implicit integration), with elastoplasticity of the reinforcing steel bars and the concrete. Various plastification and fracturation laws will be tested

  16. Measurement of perfusion using the first-pass dynamic susceptibility-weighted contrast-enhanced (DSC) MRI in neurooncology. Physical basics and clinical applications; Perfusionsmessung mit der T2*-Kontrastmitteldynamik in der Neuroonkologie. Physikalische Grundlagen und klinische Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Weber, M.-A.; Giesel, F.L.; Kauczor, H.-U.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg (Germany). Abteilung Radiologie; Risse, F.; Schad, L.R. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg (Germany). Abteilung Medizinische Physik in der Radiologie

    2005-07-01

    Perfusion imaging in the central nervous system (CNS) is mostly performed using the first-pass dynamic susceptibility-weighted contrast-enhanced (DSC) MRI. The first-pass of a contrast bolus in brain tissue is monitored by a series of T2*-weighted MR images. The susceptibility effect of the paramagnetic contrast agent leads to a signal loss that can be converted, using the principles of the indicator dilution theory, into an increase of the contrast agent concentration. From these data, parameter maps of cerebral blood volume (CBV) and flow (CBF) can be derived. Regional CBF and CBV values can be obtained by region-of-interest analysis. This review article describes physical basics of DSC MRI and summarizes the literature of DSC MRI in neurooncological issues. Studies, all with relatively limited patient numbers, report that DSC MRI is useful in the preoperative diagnosis of gliomas, CNS-lymphomas, and solitary metastases, as well as in the differentiation of these neoplastic lesions from infections and tumor-like manifestations of demyelinating disease. Additionally, DSC MRI is suitable for determining glioma grade and regions of active tumor growth which should be the target of stereotactic biopsy. After therapy, DSC MRI helps better assessing the tumor response to therapy, residual tumor after therapy, and possible treatment failure and therapy-related complications, such as radiation necrosis. The preliminary results show that DSC MRI is a diagnostic tool depicting regional variations in microvasculature of normal and diseased brains. (orig.) [German] Die MRT-Perfusionsmessungen im Zentralnervensystem (ZNS) werden derzeit hauptsaechlich mit der kontrastmittelverstaerkten T2*-Dynamik durchgefuehrt, die die Passage eines schnellen Kontrastmittelbolus mit einer Serie von T2*-gewichteten MRT-Aufnahmen verfolgt und charakterisiert. Dabei wird der Signalabfall, bedingt durch den Suszeptibilitaetseffekt des paramagnetischen Kontrastmittels, mittels geeigneter

  17. On determination of microphone response and other parameters by a hybrid experimental and numerical method

    DEFF Research Database (Denmark)

    Barrera Figueroa, Salvador; Jacobsen, Finn; Rasmussen, Knud

    2008-01-01

    to this problem is to measure the velocity distribution of the membrane by means of a non-contact method, such as laser vibrometry. The measured velocity distributions can be used together with a numerical formulation such as the Boundary Element Method for estimating the microphone response and other parameters...... such as the acoustic centres. In this work, a hybrid method is presented. The velocity distributions of condenser Laboratory Standard microphones were measured using a laser vibrometer. This measured velocity distribution was used for estimating the microphone responses and parameters. The agreement with experimental......Typically, numerical calculations of the pressure, free-field and random-incidence response of a condenser microphone are carried out on the basis of an assumed displacement distribution of the diaphragm of the microphone; the conventional assumption is that the displacement follows a Bessel...

  18. Experimental Study on the Compressive Strength of Big Mobility Concrete with Nondestructive Testing Method

    Directory of Open Access Journals (Sweden)

    Huai-Shuai Shang

    2012-01-01

    Full Text Available An experimental study of C20, C25, C30, C40, and C50 big mobility concrete cubes that came from laboratory and construction site was completed. Nondestructive testing (NDT was carried out using impact rebound hammer (IRH techniques to establish a correlation between the compressive strengths and the rebound number. The local curve for measuring strength of the regression method is set up and its superiority is proved. The rebound method presented is simple, quick, and reliable and covers wide ranges of concrete strengths. The rebound method can be easily applied to concrete specimens as well as existing concrete structures. The final results were compared with previous ones from the literature and also with actual results obtained from samples extracted from existing structures.

  19. Method of computer generation and projection recording of microholograms for holographic memory systems: mathematical modelling and experimental implementation

    International Nuclear Information System (INIS)

    Betin, A Yu; Bobrinev, V I; Evtikhiev, N N; Zherdev, A Yu; Zlokazov, E Yu; Lushnikov, D S; Markin, V V; Odinokov, S B; Starikov, S N; Starikov, R S

    2013-01-01

    A method of computer generation and projection recording of microholograms for holographic memory systems is presented; the results of mathematical modelling and experimental implementation of the method are demonstrated. (holographic memory)

  20. Experimental Methods Applied in a Study of Stall Flutter in an Axial Flow Fan

    Directory of Open Access Journals (Sweden)

    John D. Gill

    2004-01-01

    Full Text Available Flutter testing is an integral part of aircraft gas turbine engine development. In typical flutter testing blade mounted sensors in the form of strain gages and casing mounted sensors in the form of light probes (NSMS are used. Casing mounted sensors have the advantage of being non-intrusive and can detect the vibratory response of each rotating blade. Other types of casing mounted sensors can also be used to detect flutter of rotating blades. In this investigation casing mounted high frequency response pressure transducers are used to characterize the part-speed stall flutter response of a single stage unshrouded axial-flow fan. These dynamic pressure transducers are evenly spaced around the circumference at a constant axial location upstream of the fan blade leading edge plane. The pre-recorded experimental data at 70% corrected speed is analyzed for the case where the fan is back-pressured into the stall flutter zone. The experimental data is analyzed using two probe and multi-probe techniques. The analysis techniques for each method are presented. Results from these two analysis methods indicate that flutter occurred at a frequency of 411 Hz with a dominant nodal diameter of 2. The multi-probe analysis technique is a valuable method that can be used to investigate the initiation of flutter in turbomachines.

  1. Experimental results and validation of a method to reconstruct forces on the ITER test blanket modules

    International Nuclear Information System (INIS)

    Zeile, Christian; Maione, Ivan A.

    2015-01-01

    Highlights: • An in operation force measurement system for the ITER EU HCPB TBM has been developed. • The force reconstruction methods are based on strain measurements on the attachment system. • An experimental setup and a corresponding mock-up have been built. • A set of test cases representing ITER relevant excitations has been used for validation. • The influence of modeling errors on the force reconstruction has been investigated. - Abstract: In order to reconstruct forces on the test blanket modules in ITER, two force reconstruction methods, the augmented Kalman filter and a model predictive controller, have been selected and developed to estimate the forces based on strain measurements on the attachment system. A dedicated experimental setup with a corresponding mock-up has been designed and built to validate these methods. A set of test cases has been defined to represent possible excitation of the system. It has been shown that the errors in the estimated forces mainly depend on the accuracy of the identified model used by the algorithms. Furthermore, it has been found that a minimum of 10 strain gauges is necessary to allow for a low error in the reconstructed forces.

  2. Benzoic acid derivatives: Evaluation of thermochemical properties with complementary experimental and computational methods

    International Nuclear Information System (INIS)

    Verevkin, Sergey P.; Zaitsau, Dzmitry H.; Emeĺyanenko, Vladimir N.; Stepurko, Elena N.; Zherikova, Kseniya V.

    2015-01-01

    Highlights: • Vapor pressures of benzoic acid derivatives were measured. • Sublimation enthalpies were derived and compared with the literature. • Thermochemical data tested for consistency using additivity rules and computations. • Contradiction between available enthalpies of sublimation was resolved. • Pairwise interactions of substituents on the benzene ring were derived. - Abstract: Molar sublimation enthalpies of the methyl- and methoxybenzoic acids were derived from the transpiration method, static method, and TGA. Thermochemical data available in the literature were collected, evaluated, and combined with own experimental results. This collection together with the new experimental results reported here has helped to resolve contradictions in the available enthalpy data and to recommend sets of sublimation and formation enthalpies for the benzoic acid derivatives. Gas-phase enthalpies of formation calculated with the G4 quantum-chemical method were in agreement with the experiment. Pairwise interactions of the methyl, methoxy, and carboxyl substituents on the benzene ring were derived and used for the development of simple group-additivity procedures for estimation of the vaporization enthalpies, gas-phase, and liquid-phase enthalpies of formation of substituted benzenes.

  3. Experimental Method for Plotting S-N Curve with a Small Number of Specimens

    Directory of Open Access Journals (Sweden)

    Strzelecki Przemysław

    2016-12-01

    Full Text Available The study presents two approaches to plotting an S-N curve based on the experimental results. The first approach is commonly used by researchers and presented in detail in many studies and standard documents. The model uses a linear regression whose parameters are estimated by using the least squares method. A staircase method is used for an unlimited fatigue life criterion. The second model combines the S-N curve defined as a straight line and the record of random occurrence of the fatigue limit. A maximum likelihood method is used to estimate the S-N curve parameters. Fatigue data for C45+C steel obtained in the torsional bending test were used to compare the estimated S-N curves. For pseudo-random numbers generated by using the Mersenne Twister algorithm, the estimated S-N curve for 10 experimental results plotted by using the second model, estimates the fatigue life in the scatter band of the factor 3. The result gives good approximation, especially regarding the time required to plot the S-N curve.

  4. Verification of experimental dynamic strength methods with atomistic ramp-release simulations

    Science.gov (United States)

    Moore, Alexander P.; Brown, Justin L.; Lim, Hojun; Lane, J. Matthew D.

    2018-05-01

    Material strength and moduli can be determined from dynamic high-pressure ramp-release experiments using an indirect method of Lagrangian wave profile analysis of surface velocities. This method, termed self-consistent Lagrangian analysis (SCLA), has been difficult to calibrate and corroborate with other experimental methods. Using nonequilibrium molecular dynamics, we validate the SCLA technique by demonstrating that it accurately predicts the same bulk modulus, shear modulus, and strength as those calculated from the full stress tensor data, especially where strain rate induced relaxation effects and wave attenuation are small. We show here that introducing a hold in the loading profile at peak pressure gives improved accuracy in the shear moduli and relaxation-adjusted strength by reducing the effect of wave attenuation. When rate-dependent effects coupled with wave attenuation are large, we find that Lagrangian analysis overpredicts the maximum unload wavespeed, leading to increased error in the measured dynamic shear modulus. These simulations provide insight into the definition of dynamic strength, as well as a plausible explanation for experimental disagreement in reported dynamic strength values.

  5. Benzoic acid derivatives: Evaluation of thermochemical properties with complementary experimental and computational methods

    Energy Technology Data Exchange (ETDEWEB)

    Verevkin, Sergey P., E-mail: sergey.verevkin@uni-rostock.de [Department of Physical Chemistry and Department “Science and Technology of Life, Light and Matter”, University of Rostock, D-18059 Rostock (Germany); Department of Physical Chemistry, Kazan Federal University, 420008 Kazan (Russian Federation); Zaitsau, Dzmitry H. [Department of Physical Chemistry, Kazan Federal University, 420008 Kazan (Russian Federation); Emeĺyanenko, Vladimir N. [Department of Physical Chemistry and Department “Science and Technology of Life, Light and Matter”, University of Rostock, D-18059 Rostock (Germany); Stepurko, Elena N. [Chemistry Faculty and Research Institute for Physical Chemical Problems, Belarusian State University, 220030 Minsk (Belarus); Zherikova, Kseniya V. [Nikolaev Institute of Inorganic Chemistry of Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation)

    2015-12-20

    Highlights: • Vapor pressures of benzoic acid derivatives were measured. • Sublimation enthalpies were derived and compared with the literature. • Thermochemical data tested for consistency using additivity rules and computations. • Contradiction between available enthalpies of sublimation was resolved. • Pairwise interactions of substituents on the benzene ring were derived. - Abstract: Molar sublimation enthalpies of the methyl- and methoxybenzoic acids were derived from the transpiration method, static method, and TGA. Thermochemical data available in the literature were collected, evaluated, and combined with own experimental results. This collection together with the new experimental results reported here has helped to resolve contradictions in the available enthalpy data and to recommend sets of sublimation and formation enthalpies for the benzoic acid derivatives. Gas-phase enthalpies of formation calculated with the G4 quantum-chemical method were in agreement with the experiment. Pairwise interactions of the methyl, methoxy, and carboxyl substituents on the benzene ring were derived and used for the development of simple group-additivity procedures for estimation of the vaporization enthalpies, gas-phase, and liquid-phase enthalpies of formation of substituted benzenes.

  6. Experimental implementation of a low-frequency global sound equalization method based on free field propagation

    DEFF Research Database (Denmark)

    Santillan, Arturo Orozco; Pedersen, Christian Sejer; Lydolf, Morten

    2007-01-01

    An experimental implementation of a global sound equalization method in a rectangular room using active control is described in this paper. The main purpose of the work has been to provide experimental evidence that sound can be equalized in a continuous three-dimensional region, the listening zone......, which occupies a considerable part of the complete volume of the room. The equalization method, based on the simulation of a progressive plane wave, was implemented in a room with inner dimensions of 2.70 m x 2.74 m x 2.40 m. With this method,the sound was reproduced by a matrix of 4 x 5 loudspeakers...... in one of the walls. After traveling through the room, the sound wave was absorbed on the opposite wall, which had a similar arrangement of loudspeakers, by means of active control. A set of 40 digital FIR filters was used to modify the original input signal before it was fed to the loudspeakers, one...

  7. A novel experimental mechanics method for measuring the light pressure acting on a solar sail membrane

    Science.gov (United States)

    Shi, Aiming; Jiang, Li; Dowell, Earl H.; Qin, Zhixuan

    2017-02-01

    Solar sail is a high potential `sailing craft' for interstellar exploration. The area of the first flight solar sail demonstrator named "IKAROS" is 200 square meters. Future interplanetary missions will require solar sails at least on the order of 10000 square meters (or larger). Due to the limitation of ground facilities, the size of experimental sample should not be large. Furthermore the ground experiments have to be conducted in gravitational field, so the gravity effect must be considered in a ground test. To obtain insight into the solar sail membrane dynamics, a key membrane flutter (or limit cycle oscillations) experiment with light forces acting on it must be done. But one big challenge is calibrating such a tiny light force by as a function of the input power. In this paper, a gravity-based measuring method for light pressure acting on membrane is presented. To explain the experimental principle, an ideal example of a laser beam with expanders and a metal film is studied. Based on calculations, this experimental mechanics method for calibrating light pressure with an accuracy of 0.01 micro-Newton may be realized by making the light force balance the gravity force on the metal films. This gravity-based measuring method could not only be applied to study the dynamics characteristics of solar sail membrane structure with different light forces, but could also be used to determine more accurate light forces/loads acting on solar sail films and hence to enhance the determination of the mechanical properties of the solar sail membrane structure.

  8. A dual tracer ratio method for comparative emission measurements in an experimental dairy housing

    Science.gov (United States)

    Mohn, Joachim; Zeyer, Kerstin; Keck, Margret; Keller, Markus; Zähner, Michael; Poteko, Jernej; Emmenegger, Lukas; Schrade, Sabine

    2018-04-01

    Agriculture, and in particular dairy farming, is an important source of ammonia (NH3) and non-carbon dioxide greenhouse gas (GHG) emissions. This calls for the development and quantification of effective mitigation strategies. Our study presents the implementation of a dual tracer ratio method in a novel experimental dairy housing with two identical, but spatially separated housing areas. Modular design and flexible floor elements allow the assessment of structural, process engineering and organisational abatement measures at practical scale. Thereby, the emission reduction potential of specific abatement measures can be quantified in relation to a reference system. Emissions in the naturally ventilated housing are determined by continuous dosing of two artificial tracers (sulphur hexafluoride SF6, trifluoromethylsulphur pentafluoride SF5CF3) and their real-time detection in the ppt range with an optimized GC-ECD method. The two tracers are dosed into different experimental sections, which enables the independent assessment of both housing areas. Mass flow emissions of NH3 and GHGs are quantified by areal dosing of tracer gases and multipoint sampling as well as real-time analysis of both tracer and target gases. Validation experiments demonstrate that the technique is suitable for both areal and point emission sources and achieves an uncertainty of less than 10% for the mass emissions of NH3, methane (CH4) and carbon dioxide (CO2), which is superior to other currently available methods. Comparative emission measurements in this experimental dairy housing will provide reliable, currently unavailable information on emissions for Swiss dairy farming and demonstrate the reduction potential of mitigation measures for NH3, GHGs and potentially other pollutants.

  9. Summary on experimental methods for statistical transient analysis of two-phase gas-liquid flow

    International Nuclear Information System (INIS)

    Delhaye, J.M.; Jones, O.C. Jr.

    1976-06-01

    Much work has been done in the study of two-phase gas-liquid flows. Although it has been recognized superficially that such flows are not homogeneous in general, little attention has been paid to the inherent discreteness of the two-phase systems. Only relatively recently have fluctuating characteristics of two-phase flows been studied in detail. As a result, new experimental devices and techniques have been developed for use in measuring quantities previously ignored. This report reviews and summarizes most of these methods in an effort to emphasize the importance of the fluctuating nature of these flows and as a guide to further research in this field

  10. Pseudo-cubic thin-plate type Spline method for analyzing experimental data

    Energy Technology Data Exchange (ETDEWEB)

    Crecy, F de

    1994-12-31

    A mathematical tool, using pseudo-cubic thin-plate type Spline, has been developed for analysis of experimental data points. The main purpose is to obtain, without any a priori given model, a mathematical predictor with related uncertainties, usable at any point in the multidimensional parameter space. The smoothing parameter is determined by a generalized cross validation method. The residual standard deviation obtained is significantly smaller than that of a least square regression. An example of use is given with critical heat flux data, showing a significant decrease of the conception criterion (minimum allowable value of the DNB ratio). (author) 4 figs., 1 tab., 7 refs.

  11. Pseudo-cubic thin-plate type Spline method for analyzing experimental data

    International Nuclear Information System (INIS)

    Crecy, F. de.

    1993-01-01

    A mathematical tool, using pseudo-cubic thin-plate type Spline, has been developed for analysis of experimental data points. The main purpose is to obtain, without any a priori given model, a mathematical predictor with related uncertainties, usable at any point in the multidimensional parameter space. The smoothing parameter is determined by a generalized cross validation method. The residual standard deviation obtained is significantly smaller than that of a least square regression. An example of use is given with critical heat flux data, showing a significant decrease of the conception criterion (minimum allowable value of the DNB ratio). (author) 4 figs., 1 tab., 7 refs

  12. A radioimmunoassay method for the rapid detection of Candida antibodies is experimental systematic candidiasis

    International Nuclear Information System (INIS)

    Huang, Y.; Berry, W.; Cooper, H.; Zachariah, Y.; Newman, T.

    1979-01-01

    Rabbits were employed as experimental models to evaluate a solid-phase radioimmunoassay (RIA) method for the diagnosis of systematic candidiasis. Ten rabbits were incubated subcutaneously to mimic superficial candidiasis and were found to produce no antibodies to Candida as determined by both immunodiffusion and RIA procedures. However, 94 per cent of 18 rabbits systematically infected by intravenous injection of Candida cells were observed to produce antibody as assessed by the RIA technique. These data encourage further tests with human sera and the continued development of this RIA procedure as a useful tool in the early serodiagnosis of systematic candidiasis. (Auth.)

  13. An Effective Experimental Optimization Method for Wireless Power Transfer System Design Using Frequency Domain Measurement

    Directory of Open Access Journals (Sweden)

    Sangyeong Jeong

    2017-10-01

    Full Text Available This paper proposes an experimental optimization method for a wireless power transfer (WPT system. The power transfer characteristics of a WPT system with arbitrary loads and various types of coupling and compensation networks can be extracted by frequency domain measurements. The various performance parameters of the WPT system, such as input real/imaginary/apparent power, power factor, efficiency, output power and voltage gain, can be accurately extracted in a frequency domain by a single passive measurement. Subsequently, the design parameters can be efficiently tuned by separating the overall design steps into two parts. The extracted performance parameters of the WPT system were validated with time-domain experiments.

  14. Induction methods and formation process of experimental myopia in guinea pigs

    Directory of Open Access Journals (Sweden)

    Mi-Duo Chen

    2016-03-01

    Full Text Available Myopia, especially high myopia, is one of the most important eye diseases in the world. For many years the researchers established a variety of animal models and animal experiments to explore the mechanism of development of myopia. Guinea pig is one of the most commonly used myopia models in recent years. It has obvious advantages in many aspects, and it is a kind of experimental animals which is worth to be further applied to different kinds of myopic experiments and to be studied thoroughly. This article reviews the induction methods and the forming process of the guinea pig myopia model.

  15. Integral method of treatment of experimental data from radiochemical solar neutrino detectors

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Kopylov, A.V.; Streltsov, A.V.

    1985-01-01

    An analysis is made of the statistical errors in solar neutrino detection by radiochemical detectors at different times of exposure. It is shown that short exposures (tau/sub e/ = one-half to one half-life) give minimal one-year error. The possibility is considered of the detection of the solar neutrino flux variation due to annual changes of the Earth-Sun distance. The integral method of treatment of the experimental data is described. Results are given of the statistical treatment of computer simulated data

  16. A review of methods for experimentally determining linear optics in storage rings

    International Nuclear Information System (INIS)

    Safranek, J.

    1995-01-01

    In order to maximize the brightness and provide sufficient dynamic aperture in synchrotron radiation storage rings, one must understand and control the linear optics. Control of the horizontal beta function and dispersion is important for minimizing the horizontal beam size. Control of the skew gradient distribution is important for minimizing the vertical size. In this paper, various methods for experimentally determining the optics in a storage ring will be reviewed. Recent work at the National Synchrotron Light Source X-Ray Ring will be presented as well as work done at laboratories worldwide

  17. Characterisation of 1,3-diammonium propylselenate monohydrate by XRD, FT-IR, FT-Raman, DSC and DFT studies

    Science.gov (United States)

    Thirunarayanan, S.; Arjunan, V.; Marchewka, M. K.; Mohan, S.; Atalay, Yusuf

    2016-03-01

    The crystals of 1,3-diammonium propylselenate monohydrate (DAPS) were prepared and characterised X-ray diffraction (XRD), FT-IR, FT-Raman spectroscopy, and DFT/B3LYP methods. It comprises protonated propyl ammonium moieties (diammonium propyl cations), selenate anions and water molecule which are held together by a number of hydrogen bonds and form infinite chains. The XRD data confirm the transfer of two protons from selenic acid to 1,3-diaminopropane molecule. The DAPS complex is stabilised by the presence of O-H···O and N-H···O hydrogen bonds and the electrostatic interactions as well. The N···O and O···O bond distances are 2.82-2.91 and 2.77 Å, respectively. The FT-IR and FT-Raman spectra of 1,3-diammonium propyl selenate monohydrate are recorded and the complete vibrational assignments have been discussed. The geometry is optimised by B3LYP method using 6-311G, 6-311+G and 6-311+G* basis sets and the energy, structural parameters, vibrational frequencies, IR and Raman intensities are determined. Differential scanning colorimetry (DSC) data were also presented to analyse the possibility of the phase transition. Complete natural bonding orbital (NBO) analysis is carried out to analyse the intramolecular electronic interactions and their stabilisation energies. The electrostatic potential of the complex lies in the range +1.902e × 10-2 to -1.902e × 10-2. The limits of total electron density of the complex is +8.43e × 10-2 to -8.43e × 10-2.

  18. Environmental assessment of a uranium experimental rock blasting in Portugal, using geophysical and hydrogeological methods

    International Nuclear Information System (INIS)

    Ramalho, E C; Midões, C; Costa, A; Lourenço, M C; Monteiro Santos, F A

    2012-01-01

    The Nisa uranium deposit, located in Central Portugal, has been known since the late 1960s. Some areas were explored at that time. Today, a few open pits and dumps remain in place and are a concern to local authorities. To assess the geoenvironmental problems caused by the main mining exploration composed of an experimental rock blasting, 3D electrical conductivity and resistivity models were made to develop a hydrogeological model to understand the possibility of contaminants transportation, such as uranium, from the dumps towards a dam located nearby. These 3D models were the support to show alteration layer thickness variations and fault zones at depths controlling groundwater circulation. Spectrometric surveys were also carried out and correlated with geology and geoelectrical structure. All this information was used in the construction of the 3D steady state hydrogeological model of the experimental rock blasting of Nisa. In this model, groundwater flow and the contaminant pathways were simulated. Some areas have very high radioactive values resulting from the geological formation characteristics and old dumps. However, results of the environmental assessment using geophysical and hydrogeological methods point to a critical situation restricted only to the area of the experimental rock blasting of the Nisa uranium deposit and its dumps. (paper)

  19. Experimental investigation of CO_2 separation by adsorption methods in natural gas purification

    International Nuclear Information System (INIS)

    Chen, S.J.; Fu, Y.; Huang, Y.X.; Tao, Z.C.; Zhu, M.

    2016-01-01

    Highlights: • The ideal swing adsorption tank can improve the adsorption performance. • Pure CO_2 adsorption experimental data agrees well with extended Langmuir model. • Langmuir-Freundlich model correlates CO_2/CH_4 mixture adsorption data fairly well. • The temperature increases in the order swing 2 > swing1 > static for pure CO_2 adsorption. • Swinging the adsorption tank can improve the separation efficiency. - Abstract: CO_2 separation for natural gas purification by the adsorption method was studied in detail using volumetric adsorption apparatus. The crystalline phase and microstructure of the experimental sample were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Micromeritics ASAP 2020 instrument. The XRD pattern proves that the experimental sample consists of 13X zeolites. The SEM images show that the 13X zeolites expose a large number of micro-channels on the surface of the particles. The microporous volume is 0.22 cm"3 (STP)/g. The ideal swing frequency for the adsorption tank can improve the adsorption performance of an adsorbent compared with a static adsorption tank. The pure CO_2 adsorption experimental data agrees well with the extended Langmuir model. The Langmuir-Freundlich model correlates the CO_2/CH_4 mixture adsorption experimental data fairly well. The relative errors between the simulated results and the experimental data are very little, which indicates that these fitted models are correct. The average selectivity of CO_2/CH_4 in a static and swing adsorption tank are, respectively, 3.57 and 3.93, considerably higher than 1, indicating preferential CO_2 adsorption over CH_4 in CO_2/CH_4 mixtures. This also shows that the swing can improve CO_2 separation for natural gas purification. For the three types of motion status, the temperature of the adsorption tank increased in the order swing 2 > swing1 > static state for pure CO_2 adsorption in 13X zeolites. The temperature variation decreased as the

  20. Development of advanced methods for analysis of experimental data in diffusion

    Science.gov (United States)

    Jaques, Alonso V.

    There are numerous experimental configurations and data analysis techniques for the characterization of diffusion phenomena. However, the mathematical methods for estimating diffusivities traditionally do not take into account the effects of experimental errors in the data, and often require smooth, noiseless data sets to perform the necessary analysis steps. The current methods used for data smoothing require strong assumptions which can introduce numerical "artifacts" into the data, affecting confidence in the estimated parameters. The Boltzmann-Matano method is used extensively in the determination of concentration - dependent diffusivities, D(C), in alloys. In the course of analyzing experimental data, numerical integrations and differentiations of the concentration profile are performed. These methods require smoothing of the data prior to analysis. We present here an approach to the Boltzmann-Matano method that is based on a regularization method to estimate a differentiation operation on the data, i.e., estimate the concentration gradient term, which is important in the analysis process for determining the diffusivity. This approach, therefore, has the potential to be less subjective, and in numerical simulations shows an increased accuracy in the estimated diffusion coefficients. We present a regression approach to estimate linear multicomponent diffusion coefficients that eliminates the need pre-treat or pre-condition the concentration profile. This approach fits the data to a functional form of the mathematical expression for the concentration profile, and allows us to determine the diffusivity matrix directly from the fitted parameters. Reformulation of the equation for the analytical solution is done in order to reduce the size of the problem and accelerate the convergence. The objective function for the regression can incorporate point estimations for error in the concentration, improving the statistical confidence in the estimated diffusivity matrix

  1. Experimental study on two-dimensional film flow with local measurement methods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jin-Hwa, E-mail: evo03@snu.ac.kr [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Cho, Hyoung-Kyu [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of); Kim, Seok [Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Euh, Dong-Jin, E-mail: djeuh@kaeri.re.kr [Korea Atomic Energy Research Institute, 989-111, Daedeok-daero, Yuseong-gu, Daejeon 305-600 (Korea, Republic of); Park, Goon-Cherl [Nuclear Thermal-Hydraulic Engineering Laboratory, Seoul National University, Gwanak 599, Gwanak-ro, Gwanak-gu, Seoul 151-742 (Korea, Republic of)

    2015-12-01

    Highlights: • An experimental study on the two-dimensional film flow with lateral air injection was performed. • The ultrasonic thickness gauge was used to measure the local liquid film thickness. • The depth-averaged PIV (Particle Image Velocimetry) method was applied to measure the local liquid film velocity. • The uncertainty of the depth-averaged PIV was quantified with a validation experiment. • Characteristics of two-dimensional film flow were classified following the four different flow patterns. - Abstract: In an accident condition of a nuclear reactor, multidimensional two-phase flows may occur in the reactor vessel downcomer and reactor core. Therefore, those have been regarded as important issues for an advanced thermal-hydraulic safety analysis. In particular, the multi-dimensional two-phase flow in the upper downcomer during the reflood phase of large break loss of coolant accident appears with an interaction between a downward liquid and a transverse gas flow, which determines the bypass flow rate of the emergency core coolant and subsequently, the reflood coolant flow rate. At present, some thermal-hydraulic analysis codes incorporate multidimensional modules for the nuclear reactor safety analysis. However, their prediction capability for the two-phase cross flow in the upper downcomer has not been validated sufficiently against experimental data based on local measurements. For this reason, an experimental study was carried out for the two-phase cross flow to clarify the hydraulic phenomenon and provide local measurement data for the validation of the computational tools. The experiment was performed in a 1/10 scale unfolded downcomer of Advanced Power Reactor 1400 (APR1400). Pitot tubes, a depth-averaged PIV method and ultrasonic thickness gauge were applied for local measurement of the air velocity, the liquid film velocity and the liquid film thickness, respectively. The uncertainty of the depth-averaged PIV method for the averaged

  2. Experimental study on two-dimensional film flow with local measurement methods

    International Nuclear Information System (INIS)

    Yang, Jin-Hwa; Cho, Hyoung-Kyu; Kim, Seok; Euh, Dong-Jin; Park, Goon-Cherl

    2015-01-01

    Highlights: • An experimental study on the two-dimensional film flow with lateral air injection was performed. • The ultrasonic thickness gauge was used to measure the local liquid film thickness. • The depth-averaged PIV (Particle Image Velocimetry) method was applied to measure the local liquid film velocity. • The uncertainty of the depth-averaged PIV was quantified with a validation experiment. • Characteristics of two-dimensional film flow were classified following the four different flow patterns. - Abstract: In an accident condition of a nuclear reactor, multidimensional two-phase flows may occur in the reactor vessel downcomer and reactor core. Therefore, those have been regarded as important issues for an advanced thermal-hydraulic safety analysis. In particular, the multi-dimensional two-phase flow in the upper downcomer during the reflood phase of large break loss of coolant accident appears with an interaction between a downward liquid and a transverse gas flow, which determines the bypass flow rate of the emergency core coolant and subsequently, the reflood coolant flow rate. At present, some thermal-hydraulic analysis codes incorporate multidimensional modules for the nuclear reactor safety analysis. However, their prediction capability for the two-phase cross flow in the upper downcomer has not been validated sufficiently against experimental data based on local measurements. For this reason, an experimental study was carried out for the two-phase cross flow to clarify the hydraulic phenomenon and provide local measurement data for the validation of the computational tools. The experiment was performed in a 1/10 scale unfolded downcomer of Advanced Power Reactor 1400 (APR1400). Pitot tubes, a depth-averaged PIV method and ultrasonic thickness gauge were applied for local measurement of the air velocity, the liquid film velocity and the liquid film thickness, respectively. The uncertainty of the depth-averaged PIV method for the averaged

  3. Experimental method to determine the role of helium in neutron-induced microstructural evolution

    International Nuclear Information System (INIS)

    Gelles, D.S.; Garner, F.A.

    1978-12-01

    A method is presented which allows the determination of the role of helium on microstructural evolution in complex alloys and which avoids many of the problems associated with other simulation experiments. It involves a direct comparison of the materials' response to a primary difference in fission and fusion environments, namely the rate of helium generation. This is accomplished by irradiating specimens in a fission reactor and conducting microstructural analyses which concentrate on alloy matrix regions adjacent to precipitates rich in boron or nitrogen. Procedures are outlined for calculation of background and injected helium levels as well as displacement doses generated by neutrons and alpha particles. An example of the analysis method is shown for an experimental austenitic stainless steel containing boride particles and irradiated to 3 and 7 x 10 22 n/cm 2

  4. An experimental method for making spectral emittance and surface temperature measurements of opaque surfaces

    International Nuclear Information System (INIS)

    Moore, Travis J.; Jones, Matthew R.; Tree, Dale R.; Daniel Maynes, R.; Baxter, Larry L.

    2011-01-01

    An experimental procedure has been developed to make spectral emittance and temperature measurements. The spectral emittance of an object is calculated using measurements of the spectral emissive power and of the surface temperature of the object obtained using a Fourier transform infrared (FTIR) spectrometer. A calibration procedure is described in detail which accounts for the temperature dependence of the detector. The methods used to extract the spectral emissive power and surface temperature from measured infrared spectra were validated using a blackbody radiator at known temperatures. The average error in the measured spectral emittance was 2.1% and the average difference between the temperature inferred from the recorded spectra and the temperature indicated on the blackbody radiator was 1.2%. The method was used to measure the spectral emittance of oxidized copper at various temperatures.

  5. Perturbation method for experimental determination of neutron spatial distribution in the reactor cell

    International Nuclear Information System (INIS)

    Takac, S.M.

    1972-01-01

    The method is based on perturbation of the reactor cell from a few up to few tens of percent. Measurements were performed for square lattice calls of zero power reactors Anna, NORA and RB, with metal uranium and uranium oxide fuel elements, water, heavy water and graphite moderators. Character and functional dependence of perturbations were obtained from the experimental results. Zero perturbation was determined by extrapolation thus obtaining the real physical neutron flux distribution in the reactor cell. Simple diffusion theory for partial plate cell perturbation was developed for verification of the perturbation method. The results of these calculation proved that introducing the perturbation sample in the fuel results in flattening the thermal neutron density dependent on the amplitude of the applied perturbation. Extrapolation applied for perturbed distributions was found to be justified

  6. Experimental research on charging characteristics of a solar photovoltaic system by the pressure-control method

    Institute of Scientific and Technical Information of China (English)

    Hua ZHU; Zhang-lu XU; Zi-juan CAO

    2011-01-01

    The charging characteristics of the valve-regulated lead acid (VRLA) battery driven by solar energy were experimentally studied through the pressure-control method in this paper. The aims of the research were to increase charging efficiency to make the most of solar energy and to improve charging quality to prolong life of battery. The charging process of a 12 V 12 A.h VRLA battery has been tested under the mode of a stand-alone photovoltaic (PV) system. Results show that the pressure-control method can effectively control PV charging of the VRLA battery and make the best of PV cells through the maximum power point tracking (MPPT). The damage of VRLA battery by excess oxygen accumulation can be avoided through the inner pressure control of VRLA battery. Parameters such as solar radiation intensity, charging power, inner pressure of the battery, and charging current and voltage during the charging process were measured and analyzed.

  7. Comparative study of methods on outlying data detection in experimental results

    International Nuclear Information System (INIS)

    Oliveira, P.M.S.; Munita, C.S.; Hazenfratz, R.

    2009-01-01

    The interpretation of experimental results through multivariate statistical methods might reveal the outliers existence, which is rarely taken into account by the analysts. However, their presence can influence the results interpretation, generating false conclusions. This paper shows the importance of the outliers determination for one data base of 89 samples of ceramic fragments, analyzed by neutron activation analysis. The results were submitted to five procedures to detect outliers: Mahalanobis distance, cluster analysis, principal component analysis, factor analysis, and standardized residual. The results showed that although cluster analysis is one of the procedures most used to identify outliers, it can fail by not showing the samples that are easily identified as outliers by other methods. In general, the statistical procedures for the identification of the outliers are little known by the analysts. (author)

  8. A proposed safety assurance method and its application to the fusion experimental reactor

    International Nuclear Information System (INIS)

    Okazaki, T.; Seki, Y.; Inabe, T.; Aoki, I.

    1995-01-01

    Importance categorization and hazard identification methods have been proposed for a fusion experimental reactor. A parameter, the system index, is introduced in the categorization method. The relative importance of systems with safety functions can be classified by the largeness of the system index and whether or not the system acts as a boundary for radioactive materials. This categorization can be used as the basic principle in determining structure design assessment, seismic design criteria etc. For the hazard identification the system time energy matrix is proposed, where the time and spatial distributions of hazard energies are used. This approach is formulated more systematically than an ad-hoc identification of hazard events and it is useful to select design basis events which are employed in the assessment of safety designs. (orig.)

  9. Investigation on human serum albumin and Gum Tragacanth interactions using experimental and computational methods.

    Science.gov (United States)

    Moradi, Sajad; Taran, Mojtaba; Shahlaei, Mohsen

    2018-02-01

    The study on the interaction of human serum albumin and Gum Tragacanth, a biodegradable bio-polymer, has been undertaken. For this purpose, several experimental and computational methods were used. Investigation of thermodynamic parameters and mode of interactions were carried out using Fluorescence spectroscopy in 300 and 310K. Also, a Fourier transformed infrared spectra and synchronous fluorescence spectroscopy was performed. To give detailed insight of possible interactions, docking and molecular dynamic simulations were also applied. Results show that the interaction is based on hydrogen bonding and van der Waals forces. Structural analysis implies on no adverse change in protein conformation during binding of GT. Furthermore, computational methods confirm some evidence on secondary structure enhancement of protein as a presence of combining with Gum Tragacanth. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Structural, vibrational and nuclear magnetic resonance investigations of 4-bromoisoquinoline by experimental and theoretical DFT methods.

    Science.gov (United States)

    Arjunan, V; Thillai Govindaraja, S; Jayapraksh, A; Mohan, S

    2013-04-15

    Quantum chemical calculations of energy, structural parameters and vibrational wavenumbers of 4-bromoisoquinoline (4BIQ) were carried out by using B3LYP method using 6-311++G(**), cc-pVTZ and LANL2DZ basis sets. The optimised geometrical parameters obtained by DFT calculations are in good agreement with electron diffraction data. Interpretations of the experimental FTIR and FT-Raman spectra have been reported with the aid of the theoretical wavenumbers. The differences between the observed and scaled wavenumber values of most of the fundamentals are very small. The thermodynamic parameters have also been computed. Electronic properties of the molecule were discussed through the molecular electrostatic potential surface, HOMO-LUMO energy gap and NBO analysis. To provide precise assignments of (1)H and (13)CNMR spectra, isotropic shielding and chemical shifts were calculated with the Gauge-Invariant Atomic Orbital (GIAO) method. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. [Experimental rationale for the parameters of a rapid method for oxidase activity determination].

    Science.gov (United States)

    Butorina, N N

    2010-01-01

    Experimental rationale is provided for the parameters of a rapid (1-2-min) test to concurrently determine the oxidase activity of all bacteria grown on the membrane filter after water filtration. Oxidase reagents that are the aqueous solutions of tetramethyl-p-phenylenediamine dihydrochloride and demethyl-p-phenylenediamine dihydrochloride have been first ascertained to exert no effect on the viability and enzymatic activity of bacteria after one-hour contact. An algorithm has been improved for the rapid oxidase activity test: the allowable time for bacteria to contact oxidase reagents and procedures for minimizing the effect on bacterial biochemical activity following the contact. An accelerated method based on lactose medium with tergitol 7 and Endo agar has been devised to determine coliform bacteria, by applying the rapid oxidase test: the time of a final response is 18-24 hours. The method has been included into GOST 52426-2005.

  12. Experimental substantiation of methodic of 11-13 years old boxers’ coordination development

    Directory of Open Access Journals (Sweden)

    Yong Qiang Liu

    2015-06-01

    Full Text Available Purpose: experimental substantiation of methodic of junior boxers’ coordination training. Material: in the research 18 boxers of 11-13 year old age participated. In total, during 4 months 42 trainings were conducted. Total time of coordination load’s fulfillment at each training was 15-45 minutes. Results: dynamic of results in control tests was statistically confident in the tested parameters of movements. It proves effectiveness of usage the tasks with complex-coordination orientation, accented on impact on sensor-informational and motor systems of movements in junior boxers’ trainings. Conclusions: coordination training in boxing at initial stage shall include specialized varied means and methods, which would facilitate formation of motor condition and skills’ basis. Motor condition and skills are a reserve for further rising of coordination abilities’ level of junior sportsmen.

  13. Control strategy and experimental study on a novel defrosting method for air-source heat pump

    International Nuclear Information System (INIS)

    Liang Caihua; Zhang Xiaosong; Li Xiuwei; Chen Zhenqian

    2010-01-01

    A new defrosting method - the sensible heat defrosting method, aiming at shelving the various disadvantages of the conventional reverse cycle defrosting was proposed in this paper. The mechanism and process of this method was analysed. To guarantee the reliability, the self-organizing control algorithm with self-learning function was introduced based on the cardinal fuzzy control algorithm. Moreover, the control strategy was enacted; the corresponding self-organizing fuzzy control system was developed; the Micro Controller Unit (MCU) based control unit was accomplished; and the experimental study was conducted to investigate the sample machine of air-source heat pump system. The results of the experiments showed that the self-organizing control algorithm has good control characteristic and effect. On one hand, the adverse shock from the conventional reverse cycle defrosting to the refrigeration system could be avoided through this proposed method; on the other hand, the 'oil rush' could also be eliminated. Besides, the thermal comfort could be greatly improved since the temperature fluctuation range of the supplied water is narrowed by applying this new method in practice.

  14. Ionic liquids: differential scanning calorimetry as a new indirect method for determination of vaporization enthalpies.

    Science.gov (United States)

    Verevkin, Sergey P; Emel'yanenko, Vladimir N; Zaitsau, Dzmitry H; Ralys, Ricardas V; Schick, Christoph

    2012-04-12

    Differential scanning calorimetry (DSC) has been used to measure enthalpies of synthesis reactions of the 1-alkyl-3-methylimidazolium bromide [C(n)mim][Br] ionic liquids from 1-methylimidazole and n-alkyl bromides (with n = 4, 5, 6, 7, and 8). The optimal experimental conditions have been elaborated. Enthalpies of formation of these ionic liquids in the liquid state have been determined using the DSC results according to the Hess Law. The ideal-gas enthalpies of formation of [C(n)mim][Br] were calculated using the methods of quantum chemistry. They were used together with the DSC results to derive indirectly the enthalpies of vaporization of the ionic liquids under study. In order to validate the indirect determination, the experimental vaporization enthalpy of [C(4)mim][Br] was measured by using a quartz crystal microbalance (QCM). The combination of reaction enthalpy measurements by DSC with modern high-level first-principles calculations opens valuable indirect thermochemical options to obtain values of vaporization enthalpies of ionic liquids.

  15. A novel full-field experimental method to measure the local compressibility of gas diffusion media

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Yeh-Hung; Li, Yongqiang [Electrochemical Energy Research Lab, GM R and D, Honeoye Falls, NY 14472 (United States); Rock, Jeffrey A. [GM Powertrain, Honeoye Falls, NY 14472 (United States)

    2010-05-15

    The gas diffusion medium (GDM) in a proton exchange membrane (PEM) fuel cell needs to simultaneously satisfy the requirements of transporting reactant gases, removing product water, conducting electrons and heat, and providing mechanical support to the membrane electrode assembly (MEA). Concerning the localized over-compression which may force carbon fibers and other conductive debris into the membrane to cause fuel cell failure by electronically shorting through the membrane, we have developed a novel full-field experimental method to measure the local thickness and compressibility of GDM. Applying a uniform air pressure upon a thin polyimide film bonded on the top surface of the GDM with support from the bottom by a flat metal substrate and measuring the thickness change using the 3-D digital image correlation technique with an out-of-plane displacement resolution less than 0.5 {mu}m, we have determined the local thickness and compressive stress/strain behavior in the GDM. Using the local thickness and compressibility data over an area of 11.2 mm x 11.2 mm, we numerically construct the nominal compressive response of a commercial Toray trademark TGP-H-060 based GDM subjected to compression by flat platens. Good agreement in the nominal stress/strain curves from the numerical construction and direct experimental flat-platen measurement confirms the validity of the methodology proposed in this article. The result shows that a nominal pressure of 1.4 MPa compressed between two flat platens can introduce localized compressive stress concentration of more than 3 MPa in up to 1% of the total area at various locations from several hundred micrometers to 1 mm in diameter. We believe that this full-field experimental method can be useful in GDM material and process development to reduce the local hard spots and help to mitigate the membrane shorting failure in PEM fuel cells. (author)

  16. A novel full-field experimental method to measure the local compressibility of gas diffusion media

    Science.gov (United States)

    Lai, Yeh-Hung; Li, Yongqiang; Rock, Jeffrey A.

    The gas diffusion medium (GDM) in a proton exchange membrane (PEM) fuel cell needs to simultaneously satisfy the requirements of transporting reactant gases, removing product water, conducting electrons and heat, and providing mechanical support to the membrane electrode assembly (MEA). Concerning the localized over-compression which may force carbon fibers and other conductive debris into the membrane to cause fuel cell failure by electronically shorting through the membrane, we have developed a novel full-field experimental method to measure the local thickness and compressibility of GDM. Applying a uniform air pressure upon a thin polyimide film bonded on the top surface of the GDM with support from the bottom by a flat metal substrate and measuring the thickness change using the 3-D digital image correlation technique with an out-of-plane displacement resolution less than 0.5 μm, we have determined the local thickness and compressive stress/strain behavior in the GDM. Using the local thickness and compressibility data over an area of 11.2 mm × 11.2 mm, we numerically construct the nominal compressive response of a commercial Toray™ TGP-H-060 based GDM subjected to compression by flat platens. Good agreement in the nominal stress/strain curves from the numerical construction and direct experimental flat-platen measurement confirms the validity of the methodology proposed in this article. The result shows that a nominal pressure of 1.4 MPa compressed between two flat platens can introduce localized compressive stress concentration of more than 3 MPa in up to 1% of the total area at various locations from several hundred micrometers to 1 mm in diameter. We believe that this full-field experimental method can be useful in GDM material and process development to reduce the local hard spots and help to mitigate the membrane shorting failure in PEM fuel cells.

  17. Experimental study of the burned of nuclear fuel by the gamma spectroscopy method

    International Nuclear Information System (INIS)

    Amador V, P.

    2009-01-01

    Accurate information on nuclear fuel burnup is of vital importance in reactor operation, fuel management and fuel-characteristics studies. Conventionally fuel management of the TRIGA III Reactor from the National Institute of Nuclear Research (ININ) is done through the thermal balance method (management) of the power generated during reactor operation, since it is known that with 1.24 grams of 235 U is possible to generate a power or 1 MW per day during the reactor operation. On the other hand, it is possible to calculate the operation time in days during a power of 1 MW with the help of the data registered in logs. With the information just mentioned one can calculate the quantity of 235 U consumed in the fuel during a complete period of irradiation. In order to compare and prove that the burnup values, calculated through the thermal balance method, are correct, the ININ implemented, for the first time, the gamma-ray spectroscopy method as an experimental technique to calculate the burnup of several fuel elements. Gamma-ray spectroscopy is a nondestructive method, so that the integrity of the fuel element is not affected which is of great importance. Since there is a direct relation between the activity of 137 Cs contained in the fuel elements and a series of constants which are unique for the radioisotope and for the high resolution system, the problem just simplifies in measuring the 137 Cs activities. Furthermore the 137 Cs concentration equation was developed theoretically and I wrote a computer program (AMAVAL) in Fortran. The task of this program is to calculate the concentrations and the activity through the use of the equation just mentioned and the history of each fuel element. The purpose of this is to compare and validate the experimental activities with the theoretical ones for each fuel element. (Author)

  18. THE MODERN TRENDS AND EXPERIMENTAL METHODS OF TRAINING FUTURE SPECIALISTS IN THE FIELD OF HISTRIONIC ART

    Directory of Open Access Journals (Sweden)

    Julia Sergeevna Skvortsova

    2013-11-01

    Full Text Available This article reflects the specific ways of training specialists in the sphere of histrionic art, contemporary trends and special scientific experiments in the education of actors.We consider the traditional aspects of histrionic art specialists’ occupational fitness and modern requirements upon actor’s psycho-physical training.There also follows historical parallels in studying actor’s energy in the researches of K. Stanislavsky, M. Chekhov, T. Reebo, W. James, A. Maneggetty as well as in the modern researches of L. Gracheva.And there was proved the reason for including some Yoga elements and Academician M.Norbecov’s exercises system into the actors training practice.In the article Yoga for actors considers as a system of emotional and physical preparation to the artistic creative work, as a method of self-control that let an actor be really deep in his creative condition.There also was described an advantageous result of applying at our experimental laboratory of actors Yoga classes some exercises that reveal connection of person’s carriage and his condition in the process of working on the outward demonstration of this or that emotion in order to create appropriate inner state.Object: Studying the influence on the productivity of actors’ professional education of the Yoga elements included into the actors’ psycho-technique practice training.Methods: theoretical, experimental and observational methods of research.Results: After using these methods during the classes the rate of student’s psycho-physical APPARATUS has extremely increased.The area of application: the educational process at artistic creative high schools.DOI: http://dx.doi.org/10.12731/2218-7405-2013-7-52

  19. Reliability of an experimental method to analyse the impact point on a golf ball during putting.

    Science.gov (United States)

    Richardson, Ashley K; Mitchell, Andrew C S; Hughes, Gerwyn

    2015-06-01

    This study aimed to examine the reliability of an experimental method identifying the location of the impact point on a golf ball during putting. Forty trials were completed using a mechanical putting robot set to reproduce a putt of 3.2 m, with four different putter-ball combinations. After locating the centre of the dimple pattern (centroid) the following variables were tested; distance of the impact point from the centroid, angle of the impact point from the centroid and distance of the impact point from the centroid derived from the X, Y coordinates. Good to excellent reliability was demonstrated in all impact variables reflected in very strong relative (ICC = 0.98-1.00) and absolute reliability (SEM% = 0.9-4.3%). The highest SEM% observed was 7% for the angle of the impact point from the centroid. In conclusion, the experimental method was shown to be reliable at locating the centroid location of a golf ball, therefore allowing for the identification of the point of impact with the putter head and is suitable for use in subsequent studies.

  20. Experimental Analysis of a Heat Cost Allocation Method for Apartment Buildings

    Directory of Open Access Journals (Sweden)

    Fabio Saba

    2017-03-01

    Full Text Available The correct estimate of individual thermal energy consumptions, and consequently, a fair heat cost allocation among the residents of apartment buildings with centralized heating systems, represents an important driving force towards energy saving, energy efficiency and the reduction of pollutant emissions. Nowadays, in those contexts where direct heat meters cannot be used because of the layout of the hot water distribution system, electronic Heat Cost Allocators (HCAs have the highest market share for the assessment of individual thermal energy consumptions. The uncertainty associated with the parameterization of heat cost allocation devices and the installation effects arising in real applications can negatively affect the accuracy of these devices, as far as the estimation of the individual fractions of thermal energy consumption is concerned. This work deals with the experimental analysis of a novel heat cost allocation method for apartment buildings and its comparison with conventional HCAs. The method allows the indirect estimation of the thermal energy exchanged by water radiators without the need for surface temperature measurements, reducing some of the drawbacks associated with the on-site installation. The experimental analysis was carried out in a full-scale central heating system test facility available at the Italian National Metrology Institute (INRIM and characterized by SI-traceable direct heat meters installed on each water radiator.

  1. Use of the dynamic stiffness method to interpret experimental data from a nonlinear system

    Science.gov (United States)

    Tang, Bin; Brennan, M. J.; Gatti, G.

    2018-05-01

    The interpretation of experimental data from nonlinear structures is challenging, primarily because of dependency on types and levels of excitation, and coupling issues with test equipment. In this paper, the use of the dynamic stiffness method, which is commonly used in the analysis of linear systems, is used to interpret the data from a vibration test of a controllable compressed beam structure coupled to a test shaker. For a single mode of the system, this method facilitates the separation of mass, stiffness and damping effects, including nonlinear stiffness effects. It also allows the separation of the dynamics of the shaker from the structure under test. The approach needs to be used with care, and is only suitable if the nonlinear system has a response that is predominantly at the excitation frequency. For the structure under test, the raw experimental data revealed little about the underlying causes of the dynamic behaviour. However, the dynamic stiffness approach allowed the effects due to the nonlinear stiffness to be easily determined.

  2. An experimental method to verify soil conservation by check dams on the Loess Plateau, China.

    Science.gov (United States)

    Xu, X Z; Zhang, H W; Wang, G Q; Chen, S C; Dang, W Q

    2009-12-01

    A successful experiment with a physical model requires necessary conditions of similarity. This study presents an experimental method with a semi-scale physical model. The model is used to monitor and verify soil conservation by check dams in a small watershed on the Loess Plateau of China. During experiments, the model-prototype ratio of geomorphic variables was kept constant under each rainfall event. Consequently, experimental data are available for verification of soil erosion processes in the field and for predicting soil loss in a model watershed with check dams. Thus, it can predict the amount of soil loss in a catchment. This study also mentions four criteria: similarities of watershed geometry, grain size and bare land, Froude number (Fr) for rainfall event, and soil erosion in downscaled models. The efficacy of the proposed method was confirmed using these criteria in two different downscaled model experiments. The B-Model, a large scale model, simulates watershed prototype. The two small scale models, D(a) and D(b), have different erosion rates, but are the same size. These two models simulate hydraulic processes in the B-Model. Experiment results show that while soil loss in the small scale models was converted by multiplying the soil loss scale number, it was very close to that of the B-Model. Obviously, with a semi-scale physical model, experiments are available to verify and predict soil loss in a small watershed area with check dam system on the Loess Plateau, China.

  3. Qualitative and kinetic analysis of torrefaction of lignocellulosic biomass using DSC-TGA-FTIR

    Directory of Open Access Journals (Sweden)

    Bimal Acharya

    2015-11-01

    Full Text Available Torrefaction is a thermochemical conversion technique to improve the fuel properties of lignocellulosic biomass by treating at temperature 200 ℃-300 ℃ in the minimum oxygen environment for a reasonable residence time. In this study, thermal decomposition and thermal activities of miscanthus and wheat straw during the torrefaction at 200 ℃, 275 ℃, and 300 ℃ in a nitrogen environment for 45 minutes of residence time are analyzed in a simultaneous thermogravimetric analyzer (micro TGA with a differential scanning calorimetry (DSC, and a macro-TGA. The output of the micro TGA is fed into the Fourier transform infrared spectrometry (FTIR and qualitative analysis of the gaseous product is carried out. The composition of different gas products during the torrefaction of biomass are compared critically and kinetics were analyzed. It is found that the weight loss due to degradation of initial biomass in second stage (torrefaction process is a much faster conversion process than the weight loss process in the first stage (drying process. The weight loss of biomass increases with increase in the residence time and torrefaction treatment temperatures. The yield after torrefaction is a solid bio-coal product. The torrefied product were less reactive and has nearly 25% better heating value than the raw biomass. Between the two feedstocks studied, torrefied miscanthus proved to be a more stable fuel than the torrefied wheat straw. The major gaseous components observed during torrefaction are water, carbon dioxide, carbon monoxide, 1,2-Dibromethylene.

  4. DSC and X-ray diffraction investigations of phase transitions in HxBABA and NBABA

    International Nuclear Information System (INIS)

    Usha Deniz, K.; Paranjpe, A.S.; Mirza, E.B.; Parvathanathan, P.S.; Patel, K.S.

    1979-01-01

    The phase transitions and the heats of transformation, of the hexyl (HxBABA) and nonyl (NBABA) members of the series of compounds, p-n-Alkoxybenzylidene-p-Aminobenzoic Acids, have been studied by DSC in the temperature range, - 100 0 C to 300 0 C. A scheme of transitions has been proposed for each of the compounds. X-ray diffraction measurements have been done in the smectic C(Ssub(c)) and nematic (N) phases of these materials. The results reveal that (1) the Ssub(c) phase in both compounds is of the C 1 -type, (2) Ssub(c)-type order is seen throughout the nematic phase in HxBABA, whereas in NBABA, it is seen only in the neighbourhood of the Ssub(c)-N transition, (3) the temperature dependence of the smectic layer thickness, d, and of the directly measured tilt angle, theta sub(t,d), reflect faithfully the strength of the first order transition, Ssub(c)-N, and (4) there is a marked difference between the values and the temperature variations of theta sub(t,d) and theta sub(t,c) (tilt angle calculated from d) which is not completely understood, at present

  5. Complex Heat Capacity of Lithium Borate Glasses Studied by Modulated DSC

    International Nuclear Information System (INIS)

    Matsuda, Yu; Ike, Yuji; Matsui, Chihiro; Kodama, Masao; Kojima, Seiji

    2006-01-01

    Complex heat capacity, C p * = C p ' - iC p '', of lithium borate glasses Li2O·(1-x)B2O3 (x = 0.00 - 0.33) has been investigated by Modulated DSC (MDSC). We have successfully observed the frequency dependent C p * by MDSC in the frequency range 0.01 to 0.1 Hz, and the average relaxation time of glass transition has been determined as a function of temperature. Moreover, the composition dependence of the thermal properties has been investigated. The calorimetric glass transition temperatures become higher with the increase of concentration of Li2O and show the board maximum around x = 0.26-0.28. The width of glass transition region becomes narrower as Li2O increases. These results relate to the change of the fragility of the system. It has been proven that the complex heat capacity spectroscopy by MDSC is a powerful tool to investigate the glass transition phenomena

  6. Raman scattering and modulated-DSC experiments on Potassium Germanate glasses*

    Science.gov (United States)

    Wang, N.; Novita, D.; Boolchand, P.

    2006-03-01

    We have synthesized titled glasses in the 0 modulated-DSC (MDSC) experiments. Raman lineshapes observed in the present work are quite similar to those reported by Henderson and Wang ^1. Preliminary MDSC experiments reveal glass transition temperatures, Tg(x), starting from a value of 570 C at x = 0, to decrease to 508 C near x = 0.06, and to increase thereafter almost linearly to 552 C as x increases to 0.15. On the other hand, the non-reversing enthalpy associated with Tg provides evidence of a global minimum in the 0.08 0.10 as Floppy, while those in the reversibility window as representing the Intermediate Phase^2. The space filling nature of the Intermediate Phase is, independently, corroborated by trends in molar volumes which show a broad global minimum in the 9-11% range. Identification of the three elastic phases provides a physical basis to understand the origin of the Germanate anomaly, and the electrical conductivity threshold when glasses become mechanically floppy. *Supported by NSF grant DMR 04-56472. ^1 G.S.Henderson and H.M.Wang, Eur. J. Mineral. 14, 733 (2002). ^2 P.Boolchand, G.Lucovsky, J.C. Phillips and M.F.Thorpe, Phil. Mag 85,3823 (2005).

  7. Application of Differential Scanning Calorimetry (DSC in study of phase transformations in ductile iron

    Directory of Open Access Journals (Sweden)

    R. Przeliorz

    2010-04-01

    Full Text Available The effect of heating rate on phase transformations to austenite range in ductile iron of the EN-GJS-450-10 grade was investigated. For studies of phase transformations, the technique of differential scanning calorimetry (DSC was used. Microstructure was examined by optical microscopy. The calorimetric examinations have proved that on heating three transformations occur in this grade of ductile iron, viz. magnetic transformation at the Curie temperature, pearlite→austenite transformation and ferrite→austenite transformation. An increase in the heating rate shifts the pearlite→austenite and ferrite→austenite transformations to higher temperature range. At the heating rate of 5 and 15°C/min, local extrema have been observed to occur: for pearlite→austenite transformation at 784°C and 795°C, respectively, and for ferrite→austenite transformation at 805°C and 821°C, respectively. The Curie temperature of magnetic transformation was extrapolated to a value of 740°C. Each transformation is related with a specific thermal effect. The highest value of enthalpy is accompanying the ferrite→austenite transformation, the lowest occurs in the case of pearlite→austenite transformation.

  8. A DSC study of deterioration caused by environmental chemical pollutants to parchment, a collagen-based material

    International Nuclear Information System (INIS)

    Budrugeac, Petru; Badea, Elena; Gatta, Giuseppe Della; Miu, Lucretia; Comanescu, Alina

    2010-01-01

    A DSC study of new parchments exposed at 25 o C for 1-16 weeks to controlled atmospheres containing 50 ppm of gaseous chemical pollutants (NO 2 , SO 2 , NO 2 + SO 2 ) and 50% relative humidity (RH) was performed. Samples were exposed to chemical pollutants alone, as well as after previous heating at 100 o C for 2-16 days and/or irradiating with visible light (1.7 x 10 5 lx) for 4-16 h. DSC measurements were performed in both sealed crucibles in static air atmosphere at 25-200 o C and open crucibles under gas flow (nitrogen, oxygen, synthetic air) at 25-280 o C. Analysis of DSC curves provided the variation induced by ageing on the thermodynamic parameters associated with both parchment denaturation and softening of collagen crystalline fraction. All the ageing procedures decreased both temperature and enthalpy of denaturation and increased broadness of DSC peak in function of ageing time. The occurrence of thermal oxidation peaks and/or lower temperature endothermic peaks was observed. The temperature of the first softening peak always indicated a general tendency to decrease as a function of ageing time. Shrinkage temperature of collagen fibres measured by thermomicroscopy also decreased as a result of accelerated ageing treatments.

  9. A DSC study of deterioration caused by environmental chemical pollutants to parchment, a collagen-based material

    Energy Technology Data Exchange (ETDEWEB)

    Budrugeac, Petru [National R and D Institute for Electrical Engineering, INCDIE-ICPE-CA, Splaiul Unirii 313, 030138 Bucharest (Romania); Badea, Elena, E-mail: elena.badea@unito.it [Department of Chemistry IFM, University of Turin, via Pietro Giuria 9, 10125 Torino (Italy); Gatta, Giuseppe Della [Department of Chemistry IFM, University of Turin, via Pietro Giuria 9, 10125 Torino (Italy); Miu, Lucretia [National R and D Institute for Textile and Leather-Div. Leather and Footwear, INCDTP-ICPI, str Ion Minulescu 93, 031215 Bucharest (Romania); Comanescu, Alina [National R and D Institute for Electrical Engineering, INCDIE-ICPE-CA, Splaiul Unirii 313, 030138 Bucharest (Romania)

    2010-03-10

    A DSC study of new parchments exposed at 25 {sup o}C for 1-16 weeks to controlled atmospheres containing 50 ppm of gaseous chemical pollutants (NO{sub 2}, SO{sub 2}, NO{sub 2} + SO{sub 2}) and 50% relative humidity (RH) was performed. Samples were exposed to chemical pollutants alone, as well as after previous heating at 100 {sup o}C for 2-16 days and/or irradiating with visible light (1.7 x 10{sup 5} lx) for 4-16 h. DSC measurements were performed in both sealed crucibles in static air atmosphere at 25-200 {sup o}C and open crucibles under gas flow (nitrogen, oxygen, synthetic air) at 25-280 {sup o}C. Analysis of DSC curves provided the variation induced by ageing on the thermodynamic parameters associated with both parchment denaturation and softening of collagen crystalline fraction. All the ageing procedures decreased both temperature and enthalpy of denaturation and increased broadness of DSC peak in function of ageing time. The occurrence of thermal oxidation peaks and/or lower temperature endothermic peaks was observed. The temperature of the first softening peak always indicated a general tendency to decrease as a function of ageing time. Shrinkage temperature of collagen fibres measured by thermomicroscopy also decreased as a result of accelerated ageing treatments.

  10. Systematic investigation of lard polymorphism using combined DSC and time-resolved synchrotron X-ray diffraction

    NARCIS (Netherlands)

    Kalnin, D.J.E.; Lesieur, P.; Artzner, F.; Keller, G.; Ollivon, M.

    2005-01-01

    The polymorphic behavior of lard was systematically investigated by differential scanning calorimetry (DSC) while simultaneously monitoring the formation of the different crystal forms with X-ray diffraction (XRDT). To interpret the complex polymorphic evolution of the sample analyzed by regular

  11. Bootstrap resampling: a powerful method of assessing confidence intervals for doses from experimental data

    International Nuclear Information System (INIS)

    Iwi, G.; Millard, R.K.; Palmer, A.M.; Preece, A.W.; Saunders, M.

    1999-01-01

    Bootstrap resampling provides a versatile and reliable statistical method for estimating the accuracy of quantities which are calculated from experimental data. It is an empirically based method, in which large numbers of simulated datasets are generated by computer from existing measurements, so that approximate confidence intervals of the derived quantities may be obtained by direct numerical evaluation. A simple introduction to the method is given via a detailed example of estimating 95% confidence intervals for cumulated activity in the thyroid following injection of 99m Tc-sodium pertechnetate using activity-time data from 23 subjects. The application of the approach to estimating confidence limits for the self-dose to the kidney following injection of 99m Tc-DTPA organ imaging agent based on uptake data from 19 subjects is also illustrated. Results are then given for estimates of doses to the foetus following administration of 99m Tc-sodium pertechnetate for clinical reasons during pregnancy, averaged over 25 subjects. The bootstrap method is well suited for applications in radiation dosimetry including uncertainty, reliability and sensitivity analysis of dose coefficients in biokinetic models, but it can also be applied in a wide range of other biomedical situations. (author)

  12. Isolated Liver Perfusion Using Percutaneous Methods:[ql An Experimental Study in the Pig

    International Nuclear Information System (INIS)

    Harnek, Jan; Cwikiel, Wojciech; Bergqvist, Lennart; Persson, Bo; Stridbeck, Hans

    1996-01-01

    Purpose: To develop a method for isolated perfusion of the liver using radiological methods. Methods: Twenty-one pigs, weighing about 20 kg, were divided into three groups. By transjugular and transfemoral approaches two occlusion balloons were placed in the inferior vena cava cranial and caudal, respectively, to the origin of the hepatic veins. One occlusion balloon was placed transfemorally in the common hepatic artery. Another occlusion balloon was inserted in the main branch of the portal vein via the transjugular-transhepatic approach in 11 pigs (groups 1 and 2), and in 10 pigs (group 3) by a percutaneous transhepatic route. After inflation of the balloons, patency of the isolated liver circulation was evaluated by recirculation of 99 Tc m -labelled human albumin during 30 min. Blood tests were obtained after 1, 3, 5, 10, 15, and 30 min to evaluate leakage from the liver to the systemic circulation. Results: Increasing leakage to the systemic circulation from the isolated liver circulation was observed in groups 1 and 2. In the third group the leakage was less than 10%. Conclusion: In an experimental animal model, isolated perfusion of the liver with minor leakage to the systemic circulation may be achieved using radiological methods

  13. Evaluation of the physical stability and local crystallization of amorphous terfenadine using XRD-DSC and micro-TA

    International Nuclear Information System (INIS)

    Yonemochi, Etsuo; Hoshino, Takafumi; Yoshihashi, Yasuo; Terada, Katsuhide

    2005-01-01

    It is very difficult to follow rapid changes in polymorphic transformation and crystallization and to estimate the species recrystallized from the amorphous form. The aim of this study was to clarify the structural changes of amorphous terfenadine and to evaluate the polymorphs crystallized from amorphous samples using XRD-DSC and an atomic force microscope with a thermal probe (micro-TA). Amorphous samples were prepared by grinding or rapid cooling of the melt. The rapid structural transitions of samples were followed by the XRD-DSC system. On the DSC trace of the quenched terfenadine, two exotherms were observed, while only one exothermic peak was observed in the DSC scan of a ground sample. From the in situ data obtained by the XRD-DSC system, the stable form of terfenadine was recrystallized during heating of the ground amorphous sample, whereas the metastable form was recrystallized from the quenched amorphous sample and the crystallized polymorph changed to the stable form. Obtained data suggested that recrystallized species could be related to the homogeneity of samples. When the stored sample surface was scanned by atomic force microscopy (AFM), heterogeneous crystallization was observed. By using micro-TA, melting temperatures at various points were measured, and polymorph forms I and II were crystallized in each region. The percentages of the crystallized form I stored at 120 and 135 deg C were 47 and 79%, respectively. This result suggested that increasing the storage temperature increased the crystallization of form I, the stable form, confirming the temperature dependency of the crystallized form. The crystallization behavior of amorphous drug was affected by the annealing temperature. Micro-TA would be useful for detecting the inhomogeneities in polymorphs crystallized from amorphous drug

  14. Experimental validation of a method for removing the capacitive leakage artifact from electrical bioimpedance spectroscopy measurements

    International Nuclear Information System (INIS)

    Buendia, R; Seoane, F; Gil-Pita, R

    2010-01-01

    Often when performing electrical bioimpedance (EBI) spectroscopy measurements, the obtained EBI data present a hook-like deviation, which is most noticeable at high frequencies in the impedance plane. The deviation is due to a capacitive leakage effect caused by the presence of stray capacitances. In addition to the data deviation being remarkably noticeable at high frequencies in the phase and the reactance spectra, the measured EBI is also altered in the resistance and the modulus. If this EBI data deviation is not properly removed, it interferes with subsequent data analysis processes, especially with Cole model-based analyses. In other words, to perform any accurate analysis of the EBI spectroscopy data, the hook deviation must be properly removed. Td compensation is a method used to compensate the hook deviation present in EBI data; it consists of multiplying the obtained spectrum, Z meas (ω), by a complex exponential in the form of exp(–jωTd). Although the method is well known and accepted, Td compensation cannot entirely correct the hook-like deviation; moreover, it lacks solid scientific grounds. In this work, the Td compensation method is revisited, and it is shown that it should not be used to correct the effect of a capacitive leakage; furthermore, a more developed approach for correcting the hook deviation caused by the capacitive leakage is proposed. The method includes a novel correcting expression and a process for selecting the proper values of expressions that are complex and frequency dependent. The correctness of the novel method is validated with the experimental data obtained from measurements from three different EBI applications. The obtained results confirm the sufficiency and feasibility of the correcting method

  15. ISSLS prize winner: integrating theoretical and experimental methods for functional tissue engineering of the annulus fibrosus.

    Science.gov (United States)

    Nerurkar, Nandan L; Mauck, Robert L; Elliott, Dawn M

    2008-12-01

    Integrating theoretical and experimental approaches for annulus fibrosus (AF) functional tissue engineering. Apply a hyperelastic constitutive model to characterize the evolution of engineered AF via scalar model parameters. Validate the model and predict the response of engineered constructs to physiologic loading scenarios. There is need for a tissue engineered replacement for degenerate AF. When evaluating engineered replacements for load-bearing tissues, it is necessary to evaluate mechanical function with respect to the native tissue, including nonlinearity and anisotropy. Aligned nanofibrous poly-epsilon-caprolactone scaffolds with prescribed fiber angles were seeded with bovine AF cells and analyzed over 8 weeks, using experimental (mechanical testing, biochemistry, histology) and theoretical methods (a hyperelastic fiber-reinforced constitutive model). The linear region modulus for phi = 0 degrees constructs increased by approximately 25 MPa, and for phi = 90 degrees by approximately 2 MPa from 1 day to 8 weeks in culture. Infiltration and proliferation of AF cells into the scaffold and abundant deposition of s-GAG and aligned collagen was observed. The constitutive model had excellent fits to experimental data to yield matrix and fiber parameters that increased with time in culture. Correlations were observed between biochemical measures and model parameters. The model was successfully validated and used to simulate time-varying responses of engineered AF under shear and biaxial loading. AF cells seeded on nanofibrous scaffolds elaborated an organized, anisotropic AF-like extracellular matrix, resulting in improved mechanical properties. A hyperelastic fiber-reinforced constitutive model characterized the functional evolution of engineered AF constructs, and was used to simulate physiologically relevant loading configurations. Model predictions demonstrated that fibers resist shear even when the shearing direction does not coincide with the fiber direction

  16. Stacking interactions between carbohydrate and protein quantified by combination of theoretical and experimental methods.

    Directory of Open Access Journals (Sweden)

    Michaela Wimmerová

    Full Text Available Carbohydrate-receptor interactions are an integral part of biological events. They play an important role in many cellular processes, such as cell-cell adhesion, cell differentiation and in-cell signaling. Carbohydrates can interact with a receptor by using several types of intermolecular interactions. One of the most important is the interaction of a carbohydrate's apolar part with aromatic amino acid residues, known as dispersion interaction or CH/π interaction. In the study presented here, we attempted for the first time to quantify how the CH/π interaction contributes to a more general carbohydrate-protein interaction. We used a combined experimental approach, creating single and double point mutants with high level computational methods, and applied both to Ralstonia solanacearum (RSL lectin complexes with α-L-Me-fucoside. Experimentally measured binding affinities were compared with computed carbohydrate-aromatic amino acid residue interaction energies. Experimental binding affinities for the RSL wild type, phenylalanine and alanine mutants were -8.5, -7.1 and -4.1 kcal x mol(-1, respectively. These affinities agree with the computed dispersion interaction energy between carbohydrate and aromatic amino acid residues for RSL wild type and phenylalanine, with values -8.8, -7.9 kcal x mol(-1, excluding the alanine mutant where the interaction energy was -0.9 kcal x mol(-1. Molecular dynamics simulations show that discrepancy can be caused by creation of a new hydrogen bond between the α-L-Me-fucoside and RSL. Observed results suggest that in this and similar cases the carbohydrate-receptor interaction can be driven mainly by a dispersion interaction.

  17. Integration of experimental and computational methods for identifying geometric, thermal and diffusive properties of biomaterials

    Science.gov (United States)

    Weres, Jerzy; Kujawa, Sebastian; Olek, Wiesław; Czajkowski, Łukasz

    2016-04-01

    Knowledge of physical properties of biomaterials is important in understanding and designing agri-food and wood processing industries. In the study presented in this paper computational methods were developed and combined with experiments to enhance identification of agri-food and forest product properties, and to predict heat and water transport in such products. They were based on the finite element model of heat and water transport and supplemented with experimental data. Algorithms were proposed for image processing, geometry meshing, and inverse/direct finite element modelling. The resulting software system was composed of integrated subsystems for 3D geometry data acquisition and mesh generation, for 3D geometry modelling and visualization, and for inverse/direct problem computations for the heat and water transport processes. Auxiliary packages were developed to assess performance, accuracy and unification of data access. The software was validated by identifying selected properties and using the estimated values to predict the examined processes, and then comparing predictions to experimental data. The geometry, thermal conductivity, specific heat, coefficient of water diffusion, equilibrium water content and convective heat and water transfer coefficients in the boundary layer were analysed. The estimated values, used as an input for simulation of the examined processes, enabled reduction in the uncertainty associated with predictions.

  18. Experimental method for laser-driven flyer plates for 1-D shocks

    International Nuclear Information System (INIS)

    Paisley, D. L.; Luo, S. N.; Swift, D. C.; Loomis, E.; Johnson, R.; Greenfield, S.; Peralta, P.; Koskelo, A.; Tonks, D.

    2007-01-01

    One-dimensional shocks can be generated by impacting flyer plates accelerated to terminal velocities by a confined laser-ablated plasma. Over the past few years, we have developed this capability with our facility-size laser, TRIDENT, capable of ≥500 Joules at multi-microsecond pulse lengths to accelerate 1-D flyer plates, 8-mm diameter by 0.1-2 mm thick. Plates have been accelerated to terminal velocities of 100 to ≥500 m/s, with full recovery of the flyer and target for post mortem metallography. By properly tailoring the laser temporal and spatial profile, the expanding confined plasma accelerates the plate away from the transparent sapphire substrate, and decouples the laser parameters from shock pressure profile resulting from the plate impact on a target. Since the flyer plate is in free flight on impact with the target, minimal collateral damage occurs to either. The experimental method to launch these plates to terminal velocity, ancillary diagnostics, and representative experimental data is presented

  19. Theoretical model and experimental verification on the PID tracking method using liquid crystal optical phased array

    Science.gov (United States)

    Wang, Xiangru; Xu, Jianhua; Huang, Ziqiang; Wu, Liang; Zhang, Tianyi; Wu, Shuanghong; Qiu, Qi

    2017-02-01

    Liquid crystal optical phased array (LC-OPA) has been considered with great potential on the non-mechanical laser deflector because it is fabricated using photolithographic patterning technology which has been well advanced by the electronics and display industry. As a vital application of LC-OPA, free space laser communication has demonstrated its merits on communication bandwidth. Before data communication, ATP (acquisition, tracking and pointing) process costs relatively long time to result in a bottle-neck of free space laser communication. Meanwhile, dynamic real time accurate tracking is sensitive to keep a stable communication link. The electro-optic medium liquid crystal with low driving voltage can be used as the laser beam deflector. This paper presents a fast-track method using liquid crystal optical phased array as the beam deflector, CCD as a beacon light detector. PID (Proportion Integration Differentiation) loop algorithm is introduced as the controlling algorithm to generate the corresponding steering angle. To achieve the goal of fast and accurate tracking, theoretical analysis and experimental verification are demonstrated that PID closed-loop system can suppress the attitude random vibration. Meanwhile, theoretical analysis shows that tracking accuracy can be less than 6.5μrad, with a relative agreement with experimental results which is obtained after 10 adjustments that the tracking accuracy is less than12.6μrad.

  20. Spatial memory: Theoretical basis and comparative review on experimental methods in rodents.

    Science.gov (United States)

    Paul, Carrillo-Mora; Magda, Giordano; Abel, Santamaría

    2009-11-05

    The assessment of learning and memory in animal models has been widely employed in scientific research for a long time. Among these models, those representing diseases with primary processes of affected memory - such as amnesia, dementia, brain aging, etc. - studies dealing with the toxic effects of specific drugs, and other exploring neurodevelopment, trauma, epilepsy and neuropsychiatric disorders, are often called on to employ these tools. There is a diversity of experimental methods assessing animal learning and memory skills. Overall, mazes are the devices mostly used today to test memory in rodents; there are several types of them, but their real usefulness, advantages and applications remain to be fully established and depend on the particular variant selected by the experimenter. The aims of the present article are first, to briefly review the accumulated knowledge in regard to spatial memory tasks; second, to bring the reader information on the different types of rodent mazes available to test spatial memory; and third, to elucidate the usefulness and limitations of each of these devices.

  1. Experimental method and preliminary studies of the passive containment water film evaporation mass transfer

    Energy Technology Data Exchange (ETDEWEB)

    Li, Cheng [State Nuclear Power Technology Research, Beijing (China). Development Center; State Nuclear Power Research Institute, Beijing (China); Yang, Lin; Zhao, Wei; Zhou, Shan; Du, Wangfang; Gao, Zhan; Li, Honegsen [State Nuclear Power Technology Research, Beijing (China). Development Center

    2017-05-15

    For larger containments and higher operation parameters, characteristics of the outside cooling of the PCCS are very important for the analysis on the containment integrity. A preliminary analysis was made and a four-step experimental method was used to numerically analyze the falling water film evaporation for the advanced passive containment. Then, the water flow stability along the outside wall of the containment was studied. The results fit well with those correlations without airflow when the air velocity is less than 5.0 m/s. However, when the air velocity is larger than 5.0 m/s, the influence of the air velocity on the water film will appear and the mean water film thickness will be thicker. Based on the prototype operation parameters, experimental studies were carried and the results were compared with the Dittus-Boelter correlation within the operation ranges. A modification factor was proposed for the conservative application of this correlation for nuclear safety analysis.

  2. An equivalent method for optimization of particle tuned mass damper based on experimental parametric study

    Science.gov (United States)

    Lu, Zheng; Chen, Xiaoyi; Zhou, Ying

    2018-04-01

    A particle tuned mass damper (PTMD) is a creative combination of a widely used tuned mass damper (TMD) and an efficient particle damper (PD) in the vibration control area. The performance of a one-storey steel frame attached with a PTMD is investigated through free vibration and shaking table tests. The influence of some key parameters (filling ratio of particles, auxiliary mass ratio, and particle density) on the vibration control effects is investigated, and it is shown that the attenuation level significantly depends on the filling ratio of particles. According to the experimental parametric study, some guidelines for optimization of the PTMD that mainly consider the filling ratio are proposed. Furthermore, an approximate analytical solution based on the concept of an equivalent single-particle damper is proposed, and it shows satisfied agreement between the simulation and experimental results. This simplified method is then used for the preliminary optimal design of a PTMD system, and a case study of a PTMD system attached to a five-storey steel structure following this optimization process is presented.

  3. Estudo termoanalítico de comprimidos revestidos contendo captopril através de termogravimetria (TG e calorimetria exploratória diferencial (DSC Thermal analysis study of captopril coated tablets by thermogravimetry (TG and differential scanning calorimetry (DSC

    Directory of Open Access Journals (Sweden)

    Giovana Carolina Bazzo

    2005-09-01

    Full Text Available No presente trabalho foram desenvolvidos comprimidos de captopril revestidos com hidroxipropilmetilcelulose (HPMC, Opadry®, polivinilpirrolidona (PVP, Eudragit® E e goma laca. Foi realizado estudo termoanalítico do fármaco e das formulações através de termogravimetria (TG e calorimetria exploratória diferencial (DSC. Através da análise das curvas DSC verificou-se que não houve a ocorrência de interação entre o fármaco e os excipientes lactose, celulose microcristalina, croscarmelose sódica, Aerosil® e talco, utilizados na formulação do comprimido. Através desta técnica detectou-se a possibilidade de interação entre captopril e estearato de magnésio. De acordo com os resultados obtidos através de DSC não foram observadas alterações na cristalinidade do fármaco decorrentes dos processos de compressão e revestimento. A termogravimetria foi utilizada para o estudo da cinética de degradação do captopril e dos comprimidos. Os parâmetros cinéticos foram determinados através do método de Ozawa. Os resultados demonstraram que não houve alteração da estabilidade térmica do captopril na forma de comprimido. A formulação revestida com HPMC foi a que apresentou maior estabilidade térmica, quando comparada às demais formulações de revestimento.In the present study, captopril coated tablets with hydroxypropylmethylcellulose (HPMC, Opadry®, polyvinylpirrolidone (PVP, Eudragit® and shellac were produced. Differential scanning calorimetry (DSC and thermogravimetry (TG were used to evaluate the thermal properties of the drug and the formulations. On the basis of DSC results, captopril was found to be compatible with lactose, microcrystalline cellulose, sodium croscarmellose, Aerosil® and talc. Some possibility of interaction between drug-excipient was observed with magnesium stearate. However, additional techniques to confirm the results obtained are needed. There was no influence of mechanical treatment (tableting

  4. An experimental study on joining of severe plastic deformed aluminium materials with friction welding method

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, Mumin [Mechanical Engineering Department, Trakya University, 22030 Edirne (Turkey)], E-mail: mumins@trakya.edu.tr; Erol Akata, H.; Ozel, Kaan [Mechanical Engineering Department, Trakya University, 22030 Edirne (Turkey)

    2008-07-01

    In this study, 5083 aluminium alloys, which were exposed to severe plastic deformation, were joined with friction welding method and the variation in mechanical properties of the joints was experimentally investigated. Severe plastic deformation methods can be classified as equal channel angular pressing (ECAP) (in other words, equal cross section lateral extrusion - ECSLE) and cyclic extrusion-compression. Aluminium alloy as test material 5083 and square cross-sectional equal channel angular pressing die for severe plastic deformation were used in the study. Firstly 5083 alloys, as purchased, were joined with friction welding method. The optimum parameters for friction time, upset time, friction pressure and upset pressure, which are necessary for welding, were obtained. Afterwards, 5083 aluminium materials as purchased were prepared as square cross-section and then 1-pass severe plastic deformation was applied to specimen by equal channel angular pressing die. The obtained parts as square form were prepared as cylindrical form by machining and then the parts were joined by continuous drive friction welding equipment that was designed and produced in laboratory conditions before. Later, the tensile strengths of the parts, obtained at optimum conditions, were compared with those of the joined parts as purchased form. Then, hardness variations and microstructures of joints were examined. Finally, the obtained results were commented on.

  5. Experimental Study on Solar Cooling Tube Using Thermal/Vacuum Emptying Method

    Directory of Open Access Journals (Sweden)

    Huizhong Zhao

    2012-01-01

    Full Text Available A solar cooling tube using thermal/vacuum emptying method was experimentally studied in this paper. The coefficient of performance (COP of the solar cooling tube was mostly affected by the vacuum degree of the system. In past research, the thermal vacuum method, using an electric oven and iodine-tungsten lamp to heat up the adsorbent bed and H2O vapor to expel the air from the solar cooling tube, was used to manufacture solar cooling tubes. This paper presents a novel thermal vacuum combined with vacuum pump method allowing an increased vacuum state for producing solar cooling tubes. The following conclusions are reached: the adsorbent bed temperature of solar cooling tube could reaches up to 233°C, and this temperature is sufficient to meet desorption demand; the refrigerator power of a single solar cooling tube varies from 1 W to 12 W; the total supply refrigerating capacity is about 287 kJ; and the COP of this solar cooling tube is about 0.215.

  6. An experimental method for the optimization of anti-Compton spectrometer

    CERN Document Server

    Badran, H M

    1999-01-01

    The reduction of the Compton continuum can be achieved using a Compton suppression shield. For the first time, an experimental method is purposed for estimating the optimum dimensions of such a shield. The method can also provide information on the effect of the air gap, source geometry, gamma-ray energy, etc., on the optimum dimension of the active shield. The method employs the measurements of the Compton suppression efficiency in two dimensions using small size scintillation detectors. Two types of scintillation materials; NaI(Tl) and NE-102A plastic scintillators, were examined. The effect of gamma-ray energy and source geometry were also investigated using sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co sources with three geometries; point, cylindrical, and Marinelli shapes. The results indicate the importance of both NaI(Tl) and NE-102A guard detectors in surrounding the main detector rather than the distance above it. The ratio between the part of the guard detector above the surface of the main detector to th...

  7. Study on the Growth of Holes in Cold Spraying via Numerical Simulation and Experimental Methods

    Directory of Open Access Journals (Sweden)

    Guosheng Huang

    2016-12-01

    Full Text Available Cold spraying is a promising method for rapid prototyping due to its high deposition efficiency and high-quality bonding characteristic. However, many researchers have noticed that holes cannot be replenished and will grow larger and larger once formed, which will significantly decrease the deposition efficiency. No work has yet been done on this problem. In this paper, a computational simulation method was used to investigate the origins of these holes and the reasons for their growth. A thick copper coating was deposited around the pre-drilled, micro-size holes using a cold spraying method on copper substrate to verify the simulation results. The results indicate that the deposition efficiency inside the hole decreases as the hole become deeper and narrower. The repellant force between the particles perpendicular to the impaction direction will lead to porosity if the particles are too close. There is a much lower flattening ratio for successive particles if they are too close at the same location, because the momentum energy contributes to the former particle’s deformation. There is a high probability that the above two phenomena, resulting from high powder-feeding rate, will form the original hole, which will grow larger and larger once it is formed. It is very important to control the powder feeding rate, but the upper limit is yet to be determined by further simulation and experimental investigation.

  8. Experimental Methods and Development of Models on Diffusion of Nuclides onto Rocks

    International Nuclear Information System (INIS)

    Park, Chung-Kyun; Lee, Jae-Kwang; Baik, Min-Hoon

    2007-01-01

    In the context of nuclear waste repositories, the rock matrix can act as a barrier against radionuclide migration and matrix diffusion can be an important mechanism for delaying the arrival times to the biosphere. It takes a growing interest whether matrix diffusion is an important retarding and dispersing transport mechanism for solutes carried by groundwater in fractured porous media. It can retard solutes by spreading them from the flowing groundwater into the diluting reservoir of the interconnected pore space of the rock matrix, and providing an increased surface for sorption processes. Diffusion experiments has been carried in crystalline rocks to determine the diffusivities of some radionuclides either by through-diffusion cells or in-diffusion setups. We'd like to compare the experimental methods and their functions according to sorption properties of species

  9. The Dynamic Similitude Design Method of Thin Walled Structures and Experimental Validation

    Directory of Open Access Journals (Sweden)

    Zhong Luo

    2016-01-01

    Full Text Available For the applicability of dynamic similitude models of thin walled structures, such as engine blades, turbine discs, and cylindrical shells, the dynamic similitude design of typical thin walled structures is investigated. The governing equation of typical thin walled structures is firstly unified, which guides to establishing dynamic scaling laws of typical thin walled structures. Based on the governing equation, geometrically complete scaling law of the typical thin walled structure is derived. In order to determine accurate distorted scaling laws of typical thin walled structures, three principles are proposed and theoretically proved by combining the sensitivity analysis and governing equation. Taking the thin walled annular plate as an example, geometrically complete and distorted scaling laws can be obtained based on the principles of determining dynamic scaling laws. Furthermore, the previous five orders’ accurate distorted scaling laws of thin walled annular plates are presented and numerically validated. Finally, the effectiveness of the similitude design method is validated by experimental annular plates.

  10. Experimental design and multicriteria decision making methods for the optimization of ice cream composition

    Directory of Open Access Journals (Sweden)

    Cristian Rojas

    2012-03-01

    Full Text Available The aim of the present work was to optimize the sensorial and technological features of ice cream. The experimental work was performed in two stages: 1 optimization of lactose enzymatic hydrolysis, and 2 optimization of the process and product. For the first stage a complete factorial design was developed, optimized using both response surface and the steepest ascent method. In the second stage a mixture design was performed, combining the process variables. The product with the best sensorial acceptance, high yield and low cost was selected. The acceptance of the product was developed by an untrained taster’s panel. As a main result the sensorial and technological features of the final product were improved, establishing the optimum parameters for its elaboration.

  11. nuPRISM: An experimental method to remove neutrino interaction uncertainties from oscillation experiments

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    Future experiments propose to make precision measurements of parameters in the neutrino mixing matrix, including the possibly maximal mixing angle theta23, and an unknown CP violating phase, dCP, by comparing the event rate of neutrinos and antineutrinos observed close to, and far from the source. Such "near to far" extrapolation methods must achieve percent level understanding of neutrino and antineutrino interactions; the interaction determines the relationship between experimental observables and the oscillation probability which depends on the neutrino energy. However, recent developments over the last 5 years demonstrate that our understanding of neutrino interactions is insufficient. In particular, the interaction of neutrinos on correlated pairs of nucleons has only recently been added to neutrino interaction simulations. The identification of these processes as interactions on a single nucleon results in a significant bias to the measured mixing parameters, even when near detector i...

  12. Experimental comparison of the different methods for seismic qualification of electrical cabinets

    International Nuclear Information System (INIS)

    Buland, P.; Gauthier, G.; Simon, D.

    1993-01-01

    This paper presents the results of an experimental seismic study performed on a cabinet equipped with 96 acceleration sensitive relays located in four racks. The aim of this study is to verify the validity of the seismic qualification method proposed in the IEC 980 standard. The cabinet was primarily tested on a shaking table and the relay chatter was monitored. The interactions between the racks and the cabinet frame induce shocks which were correlated with some of the contact openings. The racks were afterwards tested individually with the accelerations recorded during the cabinet test. A comparison of relay chatter was performed for both test phases. An important reduction of relay chatter was noticed during the racks test. This is due to the fact that it is not possible to fully represent on shaking table the complex vibration environment (shocks) sustained by a rack in a cabinet

  13. Experimental Observation of the Skeletal Adaptive Repair Mechanism and Bionic Topology Optimization Method

    Directory of Open Access Journals (Sweden)

    Kaysar Rahman

    2014-01-01

    Full Text Available Bone adaptive repair theory considers that the external load is the direct source of bone remodeling; bone achieves its maintenance by remodeling some microscopic damages due to external load during the process. This paper firstly observes CT data from the whole self-repairing process in bone defects in rabbit femur. Experimental result shows that during self-repairing process there exists an interaction relationship between spongy bone and enamel bone volume changes of bone defect, that is when volume of spongy bone increases, enamel bone decreases, and when volume of spongy bone decreases, enamel bone increases. Secondly according to this feature a bone remodeling model based on cross-type reaction-diffusion system influenced by mechanical stress is proposed. Finally, this model coupled with finite element method by using the element adding and removing process is used to simulate the self-repairing process and engineering optimization problems by considering the idea of bionic topology optimization.

  14. MLFMA-accelerated Nyström method for ultrasonic scattering - Numerical results and experimental validation

    Science.gov (United States)

    Gurrala, Praveen; Downs, Andrew; Chen, Kun; Song, Jiming; Roberts, Ron

    2018-04-01

    Full wave scattering models for ultrasonic waves are necessary for the accurate prediction of voltage signals received from complex defects/flaws in practical nondestructive evaluation (NDE) measurements. We propose the high-order Nyström method accelerated by the multilevel fast multipole algorithm (MLFMA) as an improvement to the state-of-the-art full-wave scattering models that are based on boundary integral equations. We present numerical results demonstrating improvements in simulation time and memory requirement. Particularly, we demonstrate the need for higher order geom-etry and field approximation in modeling NDE measurements. Also, we illustrate the importance of full-wave scattering models using experimental pulse-echo data from a spherical inclusion in a solid, which cannot be modeled accurately by approximation-based scattering models such as the Kirchhoff approximation.

  15. Partition method and experimental validation for impact dynamics of flexible multibody system

    Science.gov (United States)

    Wang, J. Y.; Liu, Z. Y.; Hong, J. Z.

    2018-06-01

    The impact problem of a flexible multibody system is a non-smooth, high-transient, and strong-nonlinear dynamic process with variable boundary. How to model the contact/impact process accurately and efficiently is one of the main difficulties in many engineering applications. The numerical approaches being used widely in impact analysis are mainly from two fields: multibody system dynamics (MBS) and computational solid mechanics (CSM). Approaches based on MBS provide a more efficient yet less accurate analysis of the contact/impact problems, while approaches based on CSM are well suited for particularly high accuracy needs, yet require very high computational effort. To bridge the gap between accuracy and efficiency in the dynamic simulation of a flexible multibody system with contacts/impacts, a partition method is presented considering that the contact body is divided into two parts, an impact region and a non-impact region. The impact region is modeled using the finite element method to guarantee the local accuracy, while the non-impact region is modeled using the modal reduction approach to raise the global efficiency. A three-dimensional rod-plate impact experiment is designed and performed to validate the numerical results. The principle for how to partition the contact bodies is proposed: the maximum radius of the impact region can be estimated by an analytical method, and the modal truncation orders of the non-impact region can be estimated by the highest frequency of the signal measured. The simulation results using the presented method are in good agreement with the experimental results. It shows that this method is an effective formulation considering both accuracy and efficiency. Moreover, a more complicated multibody impact problem of a crank slider mechanism is investigated to strengthen this conclusion.

  16. Experimental method for investigating γd→pn photodisintegration reaction on the linearly polarized photon beam of the Erevan synchrotron

    International Nuclear Information System (INIS)

    Agababyan, K.Sh.; Adamyan, F.V.; Ajrapetyan, A.V.

    1985-01-01

    The experimental method for measuring the asymmetry of the γd → pn photodisintegration reaction on the linearly polarized photon beam of the Erevan synchrotron is described. The results of Monte Carlo calculations, the calibration of apparatus, the procedure of measurements and experimental data processing are repored

  17. Inferring regulatory networks from experimental morphological phenotypes: a computational method reverse-engineers planarian regeneration.

    Directory of Open Access Journals (Sweden)

    Daniel Lobo

    2015-06-01

    Full Text Available Transformative applications in biomedicine require the discovery of complex regulatory networks that explain the development and regeneration of anatomical structures, and reveal what external signals will trigger desired changes of large-scale pattern. Despite recent advances in bioinformatics, extracting mechanistic pathway models from experimental morphological data is a key open challenge that has resisted automation. The fundamental difficulty of manually predicting emergent behavior of even simple networks has limited the models invented by human scientists to pathway diagrams that show necessary subunit interactions but do not reveal the dynamics that are sufficient for complex, self-regulating pattern to emerge. To finally bridge the gap between high-resolution genetic data and the ability to understand and control patterning, it is critical to develop computational tools to efficiently extract regulatory pathways from the resultant experimental shape phenotypes. For example, planarian regeneration has been studied for over a century, but despite increasing insight into the pathways that control its stem cells, no constructive, mechanistic model has yet been found by human scientists that explains more than one or two key features of its remarkable ability to regenerate its correct anatomical pattern after drastic perturbations. We present a method to infer the molecular products, topology, and spatial and temporal non-linear dynamics of regulatory networks recapitulating in silico the rich dataset of morphological phenotypes resulting from genetic, surgical, and pharmacological experiments. We demonstrated our approach by inferring complete regulatory networks explaining the outcomes of the main functional regeneration experiments in the planarian literature; By analyzing all the datasets together, our system inferred the first systems-biology comprehensive dynamical model explaining patterning in planarian regeneration. This method

  18. ExNum 2016 International Symposium on Experimental Methods and Numerical Simulation in Engineering Sciences

    Directory of Open Access Journals (Sweden)

    Editorial Foreword

    2016-12-01

    Full Text Available ExNum 2016International Symposium on Experimental Methods and Numerical Simulation in Engineering SciencesSeptember 18th - 21st, 2016Conference Centre Liblice, Liblice, Czech RepublicOrganized by:Institute of Theoretical and Applied Mechanics ASCR, v.v.i.Faculty of Transportation Sciences CTU in PragueBergische Universität Wuppertal, Faculty 5 - Architecture and Civil EngineeringThe International Symposium on Experimental Methods and Numerical Simulation in Engineering Sciences continues the tradition of the Czech-German bilateral symposium founded by prof. Karl-Hans Laermann and prof. Stanislav Holý in 1985. In the following years, the symposium was extensively developed by prof. Josef Jíra. The symposium shall bring together mainly young scientists who are actively involved in experimental solid mechanics, theoretically and practically, in order to exchange experience, to report on the present state-of-art as well as on running research projects, to discuss due questions and problems and to promote the co-operation between individuals as well as between institutions. Therefore in the symposium discussions will play a highly significant role.Scientific Committeeprof. Ing. Ondřej Jiroušek, Ph.D. (Institute of Theoretical and Applied Mechanics ASCR, v.v.i.Univ.-Prof. Dr.-Ing.Dr.h.c.mult. Karl-Hans Laermann (Bergische Universität WuppertalProf. Dr.- Ing. Reinhard Harte (Bergische Universität Wuppertal, Faculty 5 - Architecture and Civil EngineeringProf. Dr.-Ing. Marc Gutermann (Hochschule BremenIng. Daniel Kytýř, Ph.D. (Czech Technical University in Prague, Faculty of Transportation SciencesIng. Petr Zlámal, Ph.D. (Institute of Theoretical and Applied Mechanics ASCR, v.v.i.Local Organizing CommitteeTomáš DoktorTomáš FílaNela KrčmářováPetr KoudelkaVeronika KoudelkováDaniel KytýřJan ŠleichrtPetr ZlámalEditorsDaniel KytýřPetr ZlámalScientific GuidanceOndřej Jiroušek

  19. An experimental-numerical method for comparative analysis of joint prosthesis; Un metodo numerico-experimental para el analisis comparativo de protesis articulares

    Energy Technology Data Exchange (ETDEWEB)

    Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

    2001-07-01

    The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs.

  20. An assessment of prediction methods of CHF in tubes with a large experimental data bank

    International Nuclear Information System (INIS)

    Leung, L.K.H.; Groeneveld, D.C.

    1993-01-01

    An assessment of prediction methods of CHF in tubes has been carried out using an expanded CHF data bank at Chalk River Laboratories (CRL). It includes eight different CHF look-up tables (two AECL versions and six USSR (or Russian) versions) and three empirical correlations. These prediction methods were developed from relatively large data bases and therefore have a wide range of application. Some limitations, however, were imposed in this study, to avoid any invalid predictions due to extrapolation of these methods. Therefore, these comparisons are limited to the specific data base that is tailored to suit the range of an individual method. This has resulted in a different number of data used in each case. The comparison of predictions against the experimental data is based on the constant inlet-condition approach (i.e., the pressure, mass flux, inlet fluid temperature and tube geometry are the primary parameters). Overall, the AECL tables have the widest range of application. They are assessed with 21 771 data points and the root-mean-square error is only 8.3%. About 60% of these data were used in the development of the AECL tables. The best version of the USSR/Russian CHF table is valid for 13 300 data points with a root-mean-square error of 8.8%. The USSR/Russian table that has the widest range of application covers a total of 18 800 data points, but the error increases to 9.3%. The range of application for empirical correlations, however, are generally much narrower than those covered by the CHF tables. The number of data used to assess these correlations is therefore further limited. Among the tested correlations, the Becker and Persson correlation covers the least amount of data (only 7 499 data points), but has the best accuracy (with a root-mean-square error of 9.71%). 33 refs., 2 figs., 3 tabs

  1. An investigation on characterizing dense coal-water slurry with ultrasound: theoretical and experimental method

    Energy Technology Data Exchange (ETDEWEB)

    Xue, M.H.; Su, M.X.; Dong, L.L.; Shang, Z.T.; Cai, X.S. [Shanghai University of Science & Technology, Shanghai (China)

    2010-07-01

    Particle size distribution and concentration in particulate two-phase flow are important parameters in a wide variety of industrial areas. For the purpose of online characterization in dense coal-water slurries, ultrasonic methods have many advantages such as avoiding dilution, the capability for being used in real time, and noninvasive testing, while light-based techniques are not capable of providing information because optical methods often require the slurry to be diluted. In this article, the modified Urick equation including temperature modification, which can be used to determine the concentration by means of the measurement of ultrasonic velocity in a coal-water slurry, is evaluated on the basis of theoretical analysis and experimental study. A combination of the coupled-phase model and the Bouguer-Lambert-Beer law is employed in this work, and the attenuation spectrum is measured within the frequency region from 3 to 12 MHz. Particle size distributions of the coal-water slurry at different volume fractions are obtained with the optimum regularization technique. Therefore, the ultrasonic technique presented in this work brings the possibility of using ultrasound for online measurements of dense slurries.

  2. Optimal Control of Diesel Engines: Numerical Methods, Applications, and Experimental Validation

    Directory of Open Access Journals (Sweden)

    Jonas Asprion

    2014-01-01

    become complex systems. The exploitation of any leftover potential during transient operation is crucial. However, even an experienced calibration engineer cannot conceive all the dynamic cross couplings between the many actuators. Therefore, a highly iterative procedure is required to obtain a single engine calibration, which in turn causes a high demand for test-bench time. Physics-based mathematical models and a dynamic optimisation are the tools to alleviate this dilemma. This paper presents the methods required to implement such an approach. The optimisation-oriented modelling of diesel engines is summarised, and the numerical methods required to solve the corresponding large-scale optimal control problems are presented. The resulting optimal control input trajectories over long driving profiles are shown to provide enough information to allow conclusions to be drawn for causal control strategies. Ways of utilising this data are illustrated, which indicate that a fully automated dynamic calibration of the engine control unit is conceivable. An experimental validation demonstrates the meaningfulness of these results. The measurement results show that the optimisation predicts the reduction of the fuel consumption and the cumulative pollutant emissions with a relative error of around 10% on highly transient driving cycles.

  3. Experimental investigation of radiation effect on human thermal comfort by Taguchi method

    International Nuclear Information System (INIS)

    Arslanoglu, Nurullah; Yigit, Abdulvahap

    2016-01-01

    Highlights: • Radiation heat flux from lighting lamps on human thermal comfort is studied. • The effect of posture position on thermal comfort is investigated. • The effect of clothing color on thermal comfort is examined. • Radiation heat flux from halogen reflector lamp increase skin temperature more. • Posture position effect on thermal comfort is less than the other parameters. - Abstract: In this study, the effect of radiation heat flux of lighting lamps on human thermal comfort was investigated by using Taguchi method. In addition, at indoor conditions, clothing color and posture position under the radiation effect on thermal comfort were also investigated. For this purpose, experiments were performed in an air conditioned laboratory room in summer and autumn seasons. The amount of temperature rise on the back was considered as performance parameter. An L8 orthogonal array was selected as an experimental plan for the third parameters mentioned above for summer and autumn seasons. The results were analyzed for the optimum conditions using signal-to-noise (S/N) ratio and ANOVA method. The optimum results were found to be clear halogen lamp as lighting lamp, white as t-shirt color, standing as posture position, in summer season. The optimum levels of the lighting lamp, t-shirt color and posture position were found to be clear halogen lamp, white, sitting in autumn season, respectively.

  4. [An experimental assessment of methods for applying intestinal sutures in intestinal obstruction].

    Science.gov (United States)

    Akhmadudinov, M G

    1992-04-01

    The results of various methods used in applying intestinal sutures in obturation were studied. Three series of experiments were conducted on 30 dogs--resection of the intestine after obstruction with the formation of anastomoses by means of double-row suture (Albert--Shmiden--Lambert) in the first series (10 dogs), by a single-row suture after V. M. Mateshchuk [correction of Mateshuku] in the second series, and bu a single-row stretching suture suggested by the author in the third series. The postoperative complications and the parameters of physical airtightness of the intestinal anastomosis were studied in dynamics in the experimental animals. The results of the study: incompetence of the anastomosis sutures in the first series 6, in the second 4, and in the third series one. Adhesions occurred in all animals of the first and second series and in 2 of the third series. Six dogs of the first series died, 4 of the second, and one of the third. Study of the dynamics of the results showed a direct connection of the complications with the parameters of the physical airtightness of the anastomosis, and the last-named with the method of the intestinal suture. Relatively better results were noted in formation of the anastomosis by means of our suggested stretshing continuous suture passed through the serous, muscular, and submucous coats of the intestine.

  5. Method of experimental and theoretical modeling for multiple pressure tube rupture for RBMK reactor

    International Nuclear Information System (INIS)

    Medvedeva, N.Y.; Goldstein, R.V.; Burrows, J.A.

    2001-01-01

    The rupture of single RBMK reactor channels has occurred at a number of stations with a variety of initiating events. It is assumed in RBMK Safety Cases that the force of the escaping fluid will not cause neighbouring channels to break. This assumption has not been justified. A chain reaction of tube breaks could over-pressurise the reactor cavity leading to catastrophic failure of the containment. To validate the claims of the RBMK Safety Cases the Electrogorsk Research and Engineering Centre, in participation with experts from the Institute of Mechanics of RAS, has developed the method of interacting multiscale physical and mathematical modelling for coupled thermophysical, hydrogasodynamic processes and deformation and break processes causing and (or) accompanying potential failures, design and beyond the design RBMK reactor accidents. To realise the method the set of rigs, physical and mathematical models and specialized computer codes are under creation. This article sets out an experimental philosophy and programme for achieving this objective to solve the problem of credibility or non-credibility for multiple fuel channel rupture in RBMK.(author)

  6. TiO2 synthesized by microwave assisted solvothermal method: Experimental and theoretical evaluation

    International Nuclear Information System (INIS)

    Moura, K.F.; Maul, J.; Albuquerque, A.R.; Casali, G.P.; Longo, E.; Keyson, D.; Souza, A.G.; Sambrano, J.R.; Santos, I.M.G.

    2014-01-01

    In this study, a microwave assisted solvothermal method was used to synthesize TiO 2 with anatase structure. The synthesis was done using Ti (IV) isopropoxide and ethanol without templates or alkalinizing agents. Changes in structural features were observed with increasing time of synthesis and evaluated using periodic quantum chemical calculations. The anatase phase was obtained after only 1 min of reaction besides a small amount of brookite phase. Experimental Raman spectra are in accordance with the theoretical one. Micrometric spheres constituted by nanometric particles were obtained for synthesis from 1 to 30 min, while spheres and sticks were observed after 60 min. - Graphical abstract: FE-SEM images of anatase obtained with different periods of synthesis associated with the order–disorder degree. Display Omitted - Highlights: • Anatase microspheres were obtained by the microwave assisted hydrothermal method. • Only ethanol and titanium isopropoxide were used as precursors during the synthesis. • Raman spectra and XRD patterns were compared with quantum chemical calculations. • Time of synthesis increased the short-range disorder in one direction and decreased in another

  7. Testing the sensitivity of Nested PCR method to detect Aspergillus fumigates in experimentally infected Sputum samples

    International Nuclear Information System (INIS)

    Ramadan, A.; Soukkaria, S.

    2013-01-01

    Fungal infections caused by Aspergillus species generally are occupying a second place among invasive fungal infections in the world, especially A. fumigatus, which is considered the main cause of invasive Aspergillosis (IA). Although IA rarely infects immunocompetent individuals, however, it can lead to death in immunocompromised patients. Therefore, it is necessary to diagnose the infection early in order to treat the disease efficiently. However, the conventional diagnostic tools, currently used to detect infections, has low sensitivity and reliability. Polymerase chain reaction (PCR) technology distribution as a molecular and high sensitive technology has allowed us to make comparative study between sensitivity of traditional currently used diagnostic method and Nested-PCR, the result of the study of sputum samples that experimentally infected with different concentrations of A.fumigatus spores ramping from 10 to10 6 spore/ml, have high sensitivity and specificity of Nested-PCR in detecting the lower concentrations, comparing with traditional diagnostic method (culture on Sabouraud media) that were negative in all concetrations. (author)

  8. Statistical method for the determination of the ignition energy of dust cloud - experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, S.; Lebecki, K.; Gillard, P.; Youinou, L.; Baudry, G. [University of Orleans, Bourges (France)

    2010-05-15

    Powdery materials such as metallic or polymer powders play a considerable role in many industrial processes. Their use requires the introduction of preventive safeguard to control the plants safety. The mitigation of an explosion hazard, according to the ATEX 137 Directive (1999/92/EU), requires the assessment of the dust ignition sensitivity. PRISME laboratory (University of Orleans) has developed an experimental set-up and methodology, using the Langlie test, for the quick determination of the explosion sensitivity of dusts. This method requires only 20 shots and ignition sensitivity is evaluated through the E{sub 50} (energy with an ignition probability of 0.5) A Hartmann tube, with a volume of 1.3l, was designed and built. Many results on the energy ignition thresholds of partially oxidised aluminium were obtained using this experimental device and compared to literature. E-50 evolution is the same as MIE but their respective values are different and MIE is lower than E{sub 50} however the link between E{sub 50} and MIE has not been elucidated In this paper, the Langlie method is explained in detail for the determination of the parameters (mean value E{sub 50} and standard deviation {sigma}) of the associated statistic law. The ignition probability versus applied energy is firstly measured for Lycopodium in order to validate the method A comparison between the normal and the lognormal law was achieved and the best fit was obtained with the lognormal law. In a second part, the Langlie test was performed on different dusts such as aluminium, cornstarch, lycopodium, coal, and PA12 in order to determine E-50 and {sigma} for each dust. The energies E{sub 05} and E{sub 10} corresponding respectively to an ignition probability of 0.05 and 0.1 are determined with the lognormal law and compared to MIE find in literature. E{sub 05} and E{sub 10} values of ignition energy were found to be very close and were in good agreement with MIE in the literature.

  9. EXPERIMENTAL INSTALLATION FOR AN ASSESSMENT OF METHODS OF WATER SUPPLY IN AN INTERNAL COMBUSTION ENGINE

    Directory of Open Access Journals (Sweden)

    A. V. Bizhaev

    2015-01-01

    Full Text Available The water additive to fuel became one of effective ways of the solution of the main problems of the piston internal combustion engines (ICE as it reduces thermal factor of the engine, toxic emissions of exhaust products, and also increases efficiency by some operating modes. The way of fuel and air mix with water feeding in the combustion chamber has a great influence on process of combustion. Experimental installation for obtaining comparative characteristics of the main methods of water supply in the ICE combustion chamber was created. It was defined that there are two ways of water supply in the combustion chamber. At the first way water feed is carried out in the form of a water fuel emulsion which moves to the combustion chamber through a nozzle by means of the fuel pump with a high pressure. At the second way water arrives with air through the spraying element - the carburetor or a nozzle. This way is very simple in difference of emulsion feeding. The easiest way is nozzles application. It was established that the emulsion as the non-uniform highly dispersed fluid can be divide into components. Therefore it is necessary to use during the feeding system operation special emulsifiers with air for the uniformity water getting to the cylinder. The system for each nozzle opening at some point was offered. System of feedback with sensors of exhaust gases temperature in a final collector for adjustment of duration of injection was worked out. It was showed that at the developed experimental stand it is possible to carry out tests at various power modes. As result it will be possible to estimate both ways of fuel and air mix with water feeding.

  10. Application of experimental plans method to formulate a self compacting cement paste

    Directory of Open Access Journals (Sweden)

    Mebrouki, A.

    2010-06-01

    Full Text Available The self-compacting concrete formulation means to elaborate a self-compacting cement paste to which will be injected aggregates. The purpose of this work is to find the composition of this cement paste containing local materials (pozzolanic cement, limestone fillers, superplasticizer and water having self-compacting properties. The use of the experimental plans method shows that it is possible to delimit an experimental field bounded by the volumetric proportions of materials composing the paste. The field was transformed in equations form conditioned by implicit constraints, defining zones of minimal shearing threshold and maximum viscosity; numerical resolution submitted to the optimization criteria permitted to define the volumetric proportions of each mixing parameter contributing to the preparation of an optimal paste. After experimental checking to validate obtained results, conclusions are that, from results given by ternary diagrams and desirability’s functions, a composition of an optimal self-compacting cement pas was obtained.

    En este trabajo se estudia la constitución de una pasta autocompactante a base de materiales locales argelinos (cemento binario de base puzolánica natural de Beni Saf y filler calizo de cantera. La reología de la pasta se estudia en función de las dosificaciones de cemento, caliza, superplastificante y agua. La fluidez de las pastas así formadas se deducen de los ensayos de escurrimiento del mini cono y del tiempo de flujo en el cono de Marsh. Utilizando el diseño estadístico de mezclas, el número de ensayos se ha visto considerablemente reducido, el problema se transformó en ecuaciones y después se resolvió numéricamente. A partir de las curvas de los diagramas ternarios, uniendo las respuestas de escurrimiento y el tiempo de flujo de las pastas en función de las dosificaciones en constituyentes y estudiando las funciones de conveniencia para cada respuesta, se terminará por deducir una

  11. Dynamic susceptibility contrast (DSC) perfusion MRI in differential diagnosis between radionecrosis and neoangiogenesis in cerebral metastases using rCBV, rCBF and K2.

    Science.gov (United States)

    Muto, Mario; Frauenfelder, Giulia; Senese, Rossana; Zeccolini, Fabio; Schena, Emiliano; Giurazza, Francesco; Jäger, Hans Rolf

    2018-07-01

    Distinction between treatment-related changes and tumour recurrence in patients who have received radiation treatment for brain metastases can be difficult on conventional MRI. In this study, we investigated the ability of dynamic susceptibility contrast (DSC) perfusion in differentiating necrotic changes from pathological angiogenesis and compared measurements of relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF) and K2, using a dedicated software. Twenty-nine patients with secondary brain tumors were included in this retrospective study and underwent DSC perfusion MRI with a 3-month follow-up imaging after chemo- or radiation-therapy. Region-of-interests were drawn around the contrast enhancing lesions and measurements of rCBV, rCBF and K2 were performed in all patients. Based on subsequent histological examination or clinico-radiological follow-up, the cohort was divided in two groups: recurrent disease and stable disease. Differences between the two groups were analyzed using the Student's t test. Sensitivity, specificity and diagnostic accuracy of rCBV measurements were analyzed considering three different cut-off values. Between patients with and without disease, only rCBV and rCBF values were significant (p < 0.05). The only cut-off value giving the best diagnostic accuracy of 100% was rCBV = 2.1 (sensitivity = 100%; specificity = 100%). Patients with tumor recurrence showed a higher mean value of rCBV (mean = 4.28, standard deviation = 2.09) than patients with necrotic-related changes (mean = 0.77, standard deviation = 0.44). DSC-MRI appears a clinically useful method to differentiate between tumor recurrence, tumor necrosis and pseudoprogression in patients treated for cerebral metastases. Relative CBV using a cut-off value of 2.1 proved to be the most accurate and reliable parameter.

  12. Investigation on welding and cutting methods for blanket support legs of fusion experimental reactors

    International Nuclear Information System (INIS)

    Tokami, Ikuhide; Nakahira, Masataka; Kurasawa, Toshimasa; Sato, Satoshi; Furuya, Kazuyuki; Hatano, Toshihisa; Takatsu, Hideyuki; Kuroda, Toshimasa.

    1996-07-01

    A toroidally-and poloidally-divided modular blanket has been proposed for a fusion experimental reactor, such as ITER, to enhance its maintainability as well as improve its fabricability. The blanket module, typically the size of 1 m wide, 1-2 m high and 0.4 m deep and the weight of 4 ton, will be supported by support legs which are extruded from back of the module and connected to a 70-100 mm thick strong back plate. The support leg has to withstand large electromagnetic force during plasma disruption and provide the way for in-situ module replacement by remote handling. For the connection method of the support leg to the back plate, a welding approach has been investigated here in terms of its high reliability against the large electromagnetic loads. For the welding approach, the support leg needs to be 70 mm thick, and the working space for welding/cutting heads are limited to 100 mm x 150 mm adjacent to the support leg. Based on a comparison of several welding methods, e.g. NGTIG, NGMIG and laser, NGTIG has been selected as a reference due to its well-established technology and the least R and D required. As for the cutting method, a plasma cutting has been given the highest priority to be pursued because of its compactness and high speed. Through preliminary design studies, the possibility of small welding/cutting heads that will work in the limited space has been shown, and maintenance route for in-situ module replacement with pre-and postfixture of the module has been investigated. Also preliminary R and Ds have resulted in; 1)the welding distortion is predictable according to the shape of weld groove and adjustable to meet the placement requirement of the module first wall, 2)the plasma cut surface can be rewelded without machining, 3)the welding/cutting time will meet the requirement of maintenance time. (author)

  13. 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.

  14. Clinical experimentation with aerosol antibiotics: current and future methods of administration

    Directory of Open Access Journals (Sweden)

    Zarogoulidis P

    2013-10-01

    Full Text Available Paul Zarogoulidis,1,2 Ioannis Kioumis,1 Konstantinos Porpodis,1 Dionysios Spyratos,1 Kosmas Tsakiridis,3 Haidong Huang,4 Qiang Li,4 J Francis Turner,5 Robert Browning,6 Wolfgang Hohenforst-Schmidt,7 Konstantinos Zarogoulidis1 1Pulmonary Department, G Papanikolaou General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece; 2Department of Interventional Pneumology, Ruhrlandklinik, West German Lung Center, University Hospital, University Duisburg-Essen, Essen, Germany; 3Cardiothoracic Surgery Department, Saint Luke Private Hospital of Health Excellence, Thessaloniki, Greece; 4Department of Respiratory Diseases, Shanghai Hospital/First Affiliated Hospital of the Second Military Medical University, Shanghai, People’s Republic of China; 5Pulmonary Medicine, University of Nevada School of Medicine, National Supercomputing Center for Energy and the Environment University of Nevada, Las Vegas, NV, USA; 6Pulmonary and Critical Care Medicine, Interventional Pulmonology, National Naval Medical Center, Walter Reed Army Medical Center, Bethesda, MD, USA; 7II Medical Department, Regional Clinic of Coburg, University of Wuerzburg, Coburg, Germany Abstract: Currently almost all antibiotics are administered by the intravenous route. Since several systems and situations require more efficient methods of administration, investigation and experimentation in drug design has produced local treatment modalities. Administration of antibiotics in aerosol form is one of the treatment methods of increasing interest. As the field of drug nanotechnology grows, new molecules have been produced and combined with aerosol production systems. In the current review, we discuss the efficiency of aerosol antibiotic studies along with aerosol production systems. The different parts of the aerosol antibiotic methodology are presented. Additionally, information regarding the drug molecules used is presented and future applications of this method are discussed

  15. AC susceptibility, XRD and DSC studies of Sm1-xGdxMn2Si2 silicides

    International Nuclear Information System (INIS)

    Kervan, S.; Kilic, A.; Gencer, A.

    2004-01-01

    X-ray powder diffraction, AC susceptibility and differential scanning calorimetry (DSC) studies were performed on the polycrystalline Sm 1-x Gd x Mn 2 Si 2 (0≤x≤1) compounds. All compounds investigated crystallize in the body-centered tetragonal ThCr 2 Si 2 -type structure with the space group I4/mmm. Substitution of Gd for Sm leads to a linear decrease of the lattice constants and the unit cell volume. The lattice constants and the unit cell volume obey Vegard's law. At low temperatures, the rare earth sublattice orders and reconfigures the ordering in the Mn sublattice. The samples with x=0.6 and 0.8 exhibit spin reorientation phenomenon. The Neel temperature T N (Mn) determined by DSC technique and the Curie temperature T C (RE) increase linearly with increasing Gd content x. The results are summarized in the x-T magnetic phase diagram

  16. DSC studies of retrogradation and amylose-lipid transition taking place in gamma-irradiated wheat starch

    International Nuclear Information System (INIS)

    Ciesla, K.; Gluszewski, W.; Eliasson, A.C.

    2006-01-01

    It has been already shown that degradation resulting from gamma irradiation induces a decrease in order of starch granules and influences gelatinisation taking place during heating of starch and flour suspensions. In presented paper, DSC (differential scanning calorimetry) studies were carried out for wheat starch, non-irradiated and irradiated using doses in the range from 5 to 30 kGy. The influence of the conditions applied during DSC measurements on the possibility to observe differences between the amylose-lipid complex transition and retrogradation taking place in the non-irradiated and particularly irradiated starch samples was checked. The better differentiation between the amylose-lipid complex transition taking place in particular samples accompanied by the better reproducity were obtained in the case of dense suspensions as compared to the watery suspensions as well as during the first analysis performed for the recrystallised gels

  17. Outcomes of experimental researches on stainless steel decontamination from radioactive contamination using electric slag remelting method

    International Nuclear Information System (INIS)

    Vurim, A.D.; Pakhnitz, A.V.; Trukhachev, A.G.; Bukhtoyarov, O.I.; Goncharov, A.Ye.

    2003-01-01

    Full text: Institute of Atomic Energy prepared and conducted the experiments the purpose of researching a possibility of applying of stainless steel electric slag remelting for its decontamination from radioactive contamination. The activities were conducted at participating of the specialists of Kurgan State University, Kurgan (Russian Federation). A stand, which includes the electroslag furnace (power - 150 kW, current - to 3000 A) and auxiliary equipment (the system of common and special ventilation, system of remote control, system of parameters measuring and registering and others) was created to conduct the experiments. The properties of slag compositions were researched in the course of experiments preparation. Oxide (CaO-Al 2 O 3 - CaO-SiO 2 - MgO-B 2 O 3 ) and fluoride-oxide (CaF 2 -SiO 2 - MgF 2 -SiO 2 ) slag systems and some their modifications were chosen to research physical and chemical properties. Physical and chemical properties of the slag systems were experimentally researched and it included: measuring of surface tension using the method of maximum pressure in a gas bubble (at the same time density was measured); measuring of slag alloys electrical conductivity; measuring of melt volt-ampere characteristics. The flue tubes of high temperature reactor gas cooling KET technological channels were chosen as a source of radioactive contaminated stainless steel. This reactor is meant for testing of the fuel pin and FA of the nuclear pulse propulsion. Decontamination effect for all the remelted flue tubes was indirectly confirmed by the outcomes of measuring of radioactive radiation dose rate of the materials, extracted of the crystallizer after experiments finishing. The outcomes of the experiments show that the following processes pass at electroslag remelting of radioactively contaminated steel: uranium extraction from steel; uranium transfer from steel to slag; saving or insignificant modification of steel initial composition; radionuclides deposing

  18. Longitudinal DSC-MRI for Distinguishing Tumor Recurrence From Pseudoprogression in Patients With a High-grade Glioma.

    Science.gov (United States)

    Boxerman, Jerrold L; Ellingson, Benjamin M; Jeyapalan, Suriya; Elinzano, Heinrich; Harris, Robert J; Rogg, Jeffrey M; Pope, Whitney B; Safran, Howard

    2017-06-01

    For patients with high-grade glioma on clinical trials it is important to accurately assess time of disease progression. However, differentiation between pseudoprogression (PsP) and progressive disease (PD) is unreliable with standard magnetic resonance imaging (MRI) techniques. Dynamic susceptibility contrast perfusion MRI (DSC-MRI) can measure relative cerebral blood volume (rCBV) and may help distinguish PsP from PD. A subset of patients with high-grade glioma on a phase II clinical trial with temozolomide, paclitaxel poliglumex, and concurrent radiation were assessed. Nine patients (3 grade III, 6 grade IV), with a total of 19 enhancing lesions demonstrating progressive enhancement (≥25% increase from nadir) on postchemoradiation conventional contrast-enhanced MRI, had serial DSC-MRI. Mean leakage-corrected rCBV within enhancing lesions was computed for all postchemoradiation time points. Of the 19 progressively enhancing lesions, 10 were classified as PsP and 9 as PD by biopsy/surgery or serial enhancement patterns during interval follow-up MRI. Mean rCBV at initial progressive enhancement did not differ significantly between PsP and PD (2.35 vs. 2.17; P=0.67). However, change in rCBV at first subsequent follow-up (-0.84 vs. 0.84; P=0.001) and the overall linear trend in rCBV after initial progressive enhancement (negative vs. positive slope; P=0.04) differed significantly between PsP and PD. Longitudinal trends in rCBV may be more useful than absolute rCBV in distinguishing PsP from PD in chemoradiation-treated high-grade gliomas with DSC-MRI. Further studies of DSC-MRI in high-grade glioma as a potential technique for distinguishing PsP from PD are indicated.

  19. Diclofenac Salts. V. Examples of Polymorphism among Diclofenac Salts with Alkyl-hydroxy Amines Studied by DSC and HSM

    OpenAIRE

    Fini, Adamo; Cavallari, Cristina; Ospitali, Francesca

    2010-01-01

    Nine diclofenac salts prepared with alkyl-hydroxy amines were analyzed for their properties to form polymorphs by DSC and HSM techniques. Thermograms of the forms prepared from water or acetone are different in most cases, suggesting frequent examples of polymorphism among these salts. Polymorph transition can be better highlighted when analysis is carried out by thermo-microscopy, which in most cases made it possible to observe the processes of melting of the metastable form and re-crystalli...

  20. Validation of the stream function method used for reconstruction of experimental ionospheric convection patterns

    Directory of Open Access Journals (Sweden)

    P.L. Israelevich

    Full Text Available In this study we test a stream function method suggested by Israelevich and Ershkovich for instantaneous reconstruction of global, high-latitude ionospheric convection patterns from a limited set of experimental observations, namely, from the electric field or ion drift velocity vector measurements taken along two polar satellite orbits only. These two satellite passes subdivide the polar cap into several adjacent areas. Measured electric fields or ion drifts can be considered as boundary conditions (together with the zero electric potential condition at the low-latitude boundary for those areas, and the entire ionospheric convection pattern can be reconstructed as a solution of the boundary value problem for the stream function without any preliminary information on ionospheric conductivities. In order to validate the stream function method, we utilized the IZMIRAN electrodynamic model (IZMEM recently calibrated by the DMSP ionospheric electrostatic potential observations. For the sake of simplicity, we took the modeled electric fields along the noon-midnight and dawn-dusk meridians as the boundary conditions. Then, the solution(s of the boundary value problem (i.e., a reconstructed potential distribution over the entire polar region is compared with the original IZMEM/DMSP electric potential distribution(s, as well as with the various cross cuts of the polar cap. It is found that reconstructed convection patterns are in good agreement with the original modelled patterns in both the northern and southern polar caps. The analysis is carried out for the winter and summer conditions, as well as for a number of configurations of the interplanetary magnetic field.

    Key words: Ionosphere (electric fields and currents; plasma convection; modelling and forecasting

  1. A real-time data transmission method based on Linux for physical experimental readout systems

    International Nuclear Information System (INIS)

    Cao Ping; Song Kezhu; Yang Junfeng

    2012-01-01

    In a typical physical experimental instrument, such as a fusion or particle physical application, the readout system generally implements an interface between the data acquisition (DAQ) system and the front-end electronics (FEE). The key task of a readout system is to read, pack, and forward the data from the FEE to the back-end data concentration center in real time. To guarantee real-time performance, the VxWorks operating system (OS) is widely used in readout systems. However, VxWorks is not an open-source OS, which gives it has many disadvantages. With the development of multi-core processor and new scheduling algorithm, Linux OS exhibits performance in real-time applications similar to that of VxWorks. It has been successfully used even for some hard real-time systems. Discussions and evaluations of real-time Linux solutions for a possible replacement of VxWorks arise naturally. In this paper, a real-time transmission method based on Linux is introduced. To reduce the number of transfer cycles for large amounts of data, a large block of contiguous memory buffer for DMA transfer is allocated by modifying the Linux Kernel (version 2.6) source code slightly. To increase the throughput for network transmission, the user software is designed into formation of parallelism. To achieve high performance in real-time data transfer from hardware to software, mapping techniques must be used to avoid unnecessary data copying. A simplified readout system is implemented with 4 readout modules in a PXI crate. This system can support up to 48 MB/s data throughput from the front-end hardware to the back-end concentration center through a Gigabit Ethernet connection. There are no restrictions on the use of this method, hardware or software, which means that it can be easily migrated to other interrupt related applications.

  2. Double-transmitting and Sextuple-receiving Borehole Transient Electromagnetic Method and Experimental Study

    Directory of Open Access Journals (Sweden)

    Bo Wang

    2017-04-01

    Full Text Available With the continuous improvement of precision requirements for borehole geophysical exploration, the application of transient electromagnetic method (from now on referred to as TEM in a borehole has become a hot spot. The conventional borehole TEM can only determine the longitudinal depth of the geological anomaly, the radial azimuth and depth cannot be resolved. A double-transmitting and sextuple-receiving borehole TEM is proposed, through which the radial anomaly is excited by the electromagnetic field generated by the double-emitting loops, and the azimuth and depth of the anomaly will be identified by the difference characteristics of the six receiving loops signals. In this paper, the response equations of the transmitting-receiving mode of double-transmitting and sextuple-receiving borehole TEM are deduced, and the response characteristics of the induction segment and the attenuation segment of the receiving loops are obtained based on the response equations under ramp function turn-off condition, providing the basis for theoretical analysis. Due to the negative value of the double-transmitting and sextuple-receiving transient electromagnetic response signals, a negative transformation algorithm under the double logarithmic coordinate system is proposed to provide the essential method for the analysis of two kinds of physical simulation experimental data of the radial azimuth and radial depth detection of the anomaly. The results show that the double-transmitting and sextuple-receiving borehole TEM has decent resolution ability in detecting the radial azimuth of the anomaly, and the effective resolution is 30°. The geometric difference among induced voltages of different measuring points can be used to evaluate the radial depth of the anomaly qualitatively. It is expected that the double-transmitting and sextuple-receiving borehole TEM can provide technical guidance for little borehole geophysical exploration in the fields of oil, natural

  3. Experimental studies of thin films deposition by magnetron sputtering method for CIGS solar cell fabrication

    Directory of Open Access Journals (Sweden)

    Gułkowski Sławomir

    2017-01-01

    Full Text Available Among a variety of the thin film solar cell technologies of second generation, copper-indium-gallium-diselenide device (CIGS with the latest highest lab cell efficiency record of 22.4 % seems to be the most promising for the power generation. This is partly due to the advantages of using low cost films of few microns thick not only as a metallic contacts but also as a main structure of the solar cell consisted of high quality semiconductor layers. This paper reports the experimental studies of the CIGS absorber formation on Soda Lime Glass substrate covered by thin molybdenum film as a back contact layer. All structures were deposited with the use of magnetron sputtering method only. Technological parameters of the deposition process such as deposition power, pressure and deposition time were optimized for each layer of the structure. Mo back contact was examined in terms of resistivity. EDS measurements were carried out to verify stoichiometric composition of CIGS absorber. Thin film of Al was used as a top contact in order to examine the quality of p-n junction. The I-V electrical characteristic of the p-n junction was analysed in terms of solar cell application.

  4. Modified method for bronchial suture by Ramirez Gama compared to separate stitches suture: experimental study

    Directory of Open Access Journals (Sweden)

    Vitor Mayer de Moura

    Full Text Available OBJECTIVE: To experimentally compare two classic techniques described for manual suture of the bronchial stump. METHODS: We used organs of pigs, with isolated trachea and lungs, preserved by refrigeration. We dissected 30 bronchi, which were divided into three groups of ten bronchi each, of 3mm, 5mm, and 7mm, respectively. In each, we performed the suture with simple, separated, extramucosal stitches in five other bronchi, and the technique proposed by Ramirez and modified by Santos et al in the other five. Once the sutures were finished, the anastomoses were tested using compressed air ventilation, applying an endotracheal pressure of 20mmHg. RESULTS: the Ramirez Gama suture was more effective in the bronchi of 3, 5 and 7 mm, and there was no air leak even after subjecting them to a tracheal pressure of 20mmHg. The simple interrupted sutures were less effective, with extravasation in six of the 15 tested bronchi, especially in the angles of the sutures. These figures were not significant (p = 0.08. CONCLUSION: manual sutures of the bronchial stumps were more effective when the modified Ramirez Gama suture was used in the caliber bronchi arms when tested with increased endotracheal pressure.

  5. Experimental analysis on removal factor of smear method in measurement of surface contamination

    International Nuclear Information System (INIS)

    Sugiura, Nobuyuki; Taira, Junichi; Takenaka, Keisuke; Yamanaka, Kazuo; Sugai, Kenji; Kosako, Toshiso

    2007-01-01

    The smear test is one of the important ways to measure surface contamination. The loose contamination under the high background radiation, which is more significant in handling non-sealed radioisotopes, can be evaluated by this method. The removal factor is defined as the ratio of the activity removed from the surface by one smear to the whole activity of the removable surface contamination. The removal factor is greatly changed by the quality and condition of surface materials. In this study, the values of removal factor at several typical surface conditions were evaluated experimentally and the practical application of those values was considered. It is required the smear should be pressed by moderate pressure when wiping the surface. The pressure from 1.0 kg to 1.5 kg per filter paper was recommended. The removal factor showed lower value in wiping by the pressure below 1.0 kg. The value of 0.5 for the removal factor could be applied to the smooth surface of linoleum, concrete coated with paint or epoxy resin, stainless steel and glass with the statistical allowance. (author)

  6. Experimental studies of thin films deposition by magnetron sputtering method for CIGS solar cell fabrication

    Science.gov (United States)

    Gułkowski, Sławomir; Krawczak, Ewelina

    2017-10-01

    Among a variety of the thin film solar cell technologies of second generation, copper-indium-gallium-diselenide device (CIGS) with the latest highest lab cell efficiency record of 22.4 % seems to be the most promising for the power generation. This is partly due to the advantages of using low cost films of few microns thick not only as a metallic contacts but also as a main structure of the solar cell consisted of high quality semiconductor layers. This paper reports the experimental studies of the CIGS absorber formation on Soda Lime Glass substrate covered by thin molybdenum film as a back contact layer. All structures were deposited with the use of magnetron sputtering method only. Technological parameters of the deposition process such as deposition power, pressure and deposition time were optimized for each layer of the structure. Mo back contact was examined in terms of resistivity. EDS measurements were carried out to verify stoichiometric composition of CIGS absorber. Thin film of Al was used as a top contact in order to examine the quality of p-n junction. The I-V electrical characteristic of the p-n junction was analysed in terms of solar cell application.

  7. Experimental Evaluation of a Method for Turbocharging Four-Stroke, Single Cylinder, Internal Combustion Engines

    Science.gov (United States)

    Buchman, Michael; Winter, Amos

    2015-11-01

    Turbocharging an engine increases specific power, improves fuel economy, reduces emissions, and lowers cost compared to a naturally aspirated engine of the same power output. These advantages make turbocharging commonplace for multi-cylinder engines. Single cylinder engineers are not commonly turbocharged due to the phase lag between the exhaust stroke, which powers the turbocharger, and the intake stroke, when air is pumped into the engine. Our proposed method of turbocharging single cylinder engines is to add an ``air capacitor'' to the intake manifold, an additional volume that acts as a buffer to store compressed air between the exhaust and intake strokes, and smooth out the pressure pulses from the turbocharger. This talk presents experimental results from a single cylinder, turbocharged diesel engine fit with various sized air capacitors. Power output from the engine was measured using a dynamometer made from a generator, with the electrical power dissipated with resistive heating elements. We found that intake air density increases with capacitor size as theoretically predicted, ranging from 40 to 60 percent depending on heat transfer. Our experiment was able to produce 29 percent more power compared to using natural aspiration. These results validated that an air capacitor and turbocharger may be a simple, cost effective means of increasing the power density of single cylinder engines.

  8. Internal stress distribution of X-ring using photoelastic experimental hybrid method

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, Alunda Ouma [Dedan Kimathi University of Technology, Nyeri (Kenya); Hawong, Jai Sug; Lim, Hyun Seok [Yeungnam University, Gyeongsan (Korea, Republic of); Shin, Dong Chul [Koje College, Geoje (Korea, Republic of)

    2014-05-15

    Sealing elements are essential parts of many machines, and are used to prevent the loss of a fluid or gas. When such fluids are not properly sealed, catastrophic failures may result. Many different types of rings have been developed to suit various industrial needs. Considerable research has been done on the O-ring. We analyze the internal stresses developed in an X-ring under a uniform squeeze rate of 20%, which is suitable for static applications, using a photoelastic experimental hybrid method. The internal pressures applied were 0.98, 1.96, 2.94, 3.92, 4.90, and 5.88 MPa. We show that sealing rings with X geometry have considerably higher internal stresses than O-ring seals. In addition, we demonstrate that after extrusion, for an internal pressure of 5.88 MPa, the two lobes on the upper contact surface merge, thereby increasing the contact length of the upper side significantly. Extrusion in the X-ring occurred when the internal pressure was 4.90 MPa.

  9. Experimental validation of a multi-energy x-ray adapted scatter separation method

    Science.gov (United States)

    Sossin, A.; Rebuffel, V.; Tabary, J.; Létang, J. M.; Freud, N.; Verger, L.

    2016-12-01

    Both in radiography and computed tomography (CT), recently emerged energy-resolved x-ray photon counting detectors enable the identification and quantification of individual materials comprising the inspected object. However, the approaches used for these operations require highly accurate x-ray images. The accuracy of the images is severely compromised by the presence of scattered radiation, which leads to a loss of spatial contrast and, more importantly, a bias in radiographic material imaging and artefacts in CT. The aim of the present study was to experimentally evaluate a recently introduced partial attenuation spectral scatter separation approach (PASSSA) adapted for multi-energy imaging. For this purpose, a prototype x-ray system was used. Several radiographic acquisitions of an anthropomorphic thorax phantom were performed. Reference primary images were obtained via the beam-stop (BS) approach. The attenuation images acquired from PASSSA-corrected data showed a substantial increase in local contrast and internal structure contour visibility when compared to uncorrected images. A substantial reduction of scatter induced bias was also achieved. Quantitatively, the developed method proved to be in relatively good agreement with the BS data. The application of the proposed scatter correction technique lowered the initial normalized root-mean-square error (NRMSE) of 45% between the uncorrected total and the reference primary spectral images by a factor of 9, thus reducing it to around 5%.

  10. [Claude Bernard, the experimental method, and the Société de Biologie].

    Science.gov (United States)

    Bange, Christian

    2009-01-01

    Claude Bernard was one of the founder of the Société de Biologie created in 1849. He actively took part to it from its very beginning by presenting various communications and several important memoirs. Epistemological thoughts found in these memoirs lead to the methodological chapters introducing the volumes of his edited lessons given at the Collège de France. In 1865, these texts formed the basis to his Introduction à l'étude de la Médecine expérimentale, in which Bernard claims the experimental method should rely on the principle of determinism of the phenomena of Life. He was a dutiful President of the Société from 1867 until his death. He nevertheless was not often involved in debates, but agreed on the defense of the scientific principles he had claimed. He remained influential until his death, as noted in 1899 by the report Engène Gley wrote on the Société de Biologie during its fifty first years. Gley points regularly to Bernard's axioms which remained the true scientific credo of French biologists.

  11. Vibration Prediction Method of Electric Machines by using Experimental Transfer Function and Magnetostatic Finite Element Analysis

    International Nuclear Information System (INIS)

    Saito, A; Kuroishi, M; Nakai, H

    2016-01-01

    This paper concerns the noise and structural vibration caused by rotating electric machines. Special attention is given to the magnetic-force induced vibration response of interior-permanent magnet machines. In general, to accurately predict and control the vibration response caused by the electric machines, it is inevitable to model not only the magnetic force induced by the fluctuation of magnetic fields, but also the structural dynamic characteristics of the electric machines and surrounding structural components. However, due to complicated boundary conditions and material properties of the components, such as laminated magnetic cores and varnished windings, it has been a challenge to compute accurate vibration response caused by the electric machines even after their physical models are available. In this paper, we propose a highly-accurate vibration prediction method that couples experimentally-obtained discrete structural transfer functions and numerically-obtained distributed magnetic-forces. The proposed vibration synthesis methodology has been applied to predict vibration responses of an interior permanent magnet machine. The results show that the predicted vibration response of the electric machine agrees very well with the measured vibration response for several load conditions, for wide frequency ranges. (paper)

  12. The birth of experimental psychology in Germany between psychophysical methods and physiological theories.

    Science.gov (United States)

    Sinatra, Maria

    2006-01-01

    In 1879 Wundt's laboratory of psychology was opened in Leipzig, and it has been the landmark ever since for the beginning of modern experimental psychology. Its founder, Wilhelm Maximilian Wundt, was the first to successfully demarcate the areas of scientific psychology as being distinct from either physiology or philosophy, thus guaranteeing the survival of psychology, which was regarded as an autonomous discipline set upon a secure institutional framework. This paper attempts to clarify the basic facts and concepts related to the roots of scientific psychology in Germany, i.e., the context in which the "Founding Father" worked, as well as of those predecessors who proposed the topics and apparatus of his laboratory. Attention will be paid in particular to the psychophysical methods of Weber and Fechner, especially in regard to colour perception. In this context, an outline is presented of the history of reaction time experiments in astronomy, physiology, and psychology, and of the role played by the scientific instruments. It is shown how the methodology of physics and physiology contributed to the emancipation of scientific psychology and to the formation of its orientation.

  13. Atmospheric River Tracking Method Intercomparison Project (ARTMIP: project goals and experimental design

    Directory of Open Access Journals (Sweden)

    C. A. Shields

    2018-06-01

    Full Text Available The Atmospheric River Tracking Method Intercomparison Project (ARTMIP is an international collaborative effort to understand and quantify the uncertainties in atmospheric river (AR science based on detection algorithm alone. Currently, there are many AR identification and tracking algorithms in the literature with a wide range of techniques and conclusions. ARTMIP strives to provide the community with information on different methodologies and provide guidance on the most appropriate algorithm for a given science question or region of interest. All ARTMIP participants will implement their detection algorithms on a specified common dataset for a defined period of time. The project is divided into two phases: Tier 1 will utilize the Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA-2 reanalysis from January 1980 to June 2017 and will be used as a baseline for all subsequent comparisons. Participation in Tier 1 is required. Tier 2 will be optional and include sensitivity studies designed around specific science questions, such as reanalysis uncertainty and climate change. High-resolution reanalysis and/or model output will be used wherever possible. Proposed metrics include AR frequency, duration, intensity, and precipitation attributable to ARs. Here, we present the ARTMIP experimental design, timeline, project requirements, and a brief description of the variety of methodologies in the current literature. We also present results from our 1-month proof-of-concept trial run designed to illustrate the utility and feasibility of the ARTMIP project.

  14. A psychometric evaluation of the Diabetes Symptom Checklist-Revised (DSC-R cognitive distress, fatigue, hyperglycemia, and hypoglycemia subscales in patients with type 1 and type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Naegeli AN

    2010-03-01

    Full Text Available April N Naegeli1, Timothy E Stump2, Risa P Hayes11Global Health Outcomes, Eli Lilly and Company, Indianapolis, IN, USA; 2Consultant, Indianapolis, IN, USAObjective: To explore the use of Diabetes Symptom Checklist-Revised (DSC-R Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia subscales as measures of acute diabetesassociated symptoms in patients with both type 1 and 2 diabetes.Research design and methods: Our study was conducted in context of two international, multicenter, randomized clinical trials for inhaled insulin. Confirmatory factor analyses and assessments of reliability and construct validity were performed.Results: Study participants were 371 patients with type 2 (56% male; mean age, 57 years and 481 with type 1 diabetes (57% male, mean age, 40 years. In both populations a four-factor model was the best fit. Cronbach’s α ≥ 0.79 and intraclass correlation coefficient ≥0.63; subscales correlated (P ≤ 0.05 with measures of well-being and satisfaction (0.12 ≤ r ≤ 0.71. In patients with type 1 diabetes, three subscales correlated (P < 0.05 with A1C.Conclusions: The psychometric properties of the DSC-R Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia suggest they may be utilized in clinical trials as reliable and valid measures of acute symptoms of diabetes.Keywords: Diabetes Symptom Checklist-Revised, DSC-R, type 1 diabetes, type 2 diabetes, psychometric validation

  15. Simplified analytical methods and experimental correlations of damping in piping during dynamic high-level inelastic response

    International Nuclear Information System (INIS)

    Severud, L.K.

    1987-01-01

    Simplified methods for predicting equivalent viscous damping are used to assess damping contributions due to piping inelastic plastic hinge action and support snubbers. These increments are compared to experimental findings from shake and snap-back tests of several pipe systems. Good correlations were found confirming the usefulness of the simplified methods

  16. Numerical calibration and experimental validation of a PCM-Air heat exchanger model

    International Nuclear Information System (INIS)

    Stathopoulos, N.; El Mankibi, M.; Santamouris, Mattheos

    2017-01-01

    Highlights: • Development of a PCM-Air heat exchanger experimental unit and its numerical model. • Differential Scanning Calorimetry for PCM properties. • Ineptitude of DSC obtained heat capacity curves. • Creation of adequate heat capacity curves depending on heat transfer rates. • Confrontation of numerical and experimental results and validation of the model. - Abstract: Ambitious goals have been set at international, European and French level for energy consumption and greenhouse gas emissions decrease of the building sector. Achieving them requires renewable energy integration, a technology that presents however an important drawback: intermittent energy production. In response, thermal energy storage (TES) technology applications have been developed in order to correlate energy production and consumption of the building. Phase Change Materials (PCMs) have been widely used in TES applications as they offer a high storage density and adequate phase change temperature range. It is important to accurately know the thermophysical properties of the PCM, both for experimental (system design) and numerical (correct prediction) purposes. In this paper, the fabrication of a PCM – Air experimental prototype is presented at first, along with the development of a numerical model simulating the downstream temperature evolution of the heat exchanger. Particular focus is given to the calibration method and the validation of the model using experimental characterization results. Differential scanning calorimetry (DSC) is used to define the thermal properties of the PCM. Initial numerical results are underestimated compared to experimental ones. Various factors were investigated, pointing to the ineptitude of the heat capacity parameter, as DSC results depend on heating/cooling rates. Adequate heat capacity curves were empirically determined, depending on heat transfer rates and based on DSC results and experimental observations. The results of the proposed model

  17. A method for assessing buildings’ energy efficiency by dynamic simulation and experimental activity

    International Nuclear Information System (INIS)

    Pisello, Anna Laura; Goretti, Michele; Cotana, Franco

    2012-01-01

    Highlights: ► We propose a new methodology for the evaluation of buildings’ thermal-energetic performance. ► We express year-round performance by an appropriate objective function. ► The procedure allows to translate dynamic simulation results into buildings’ energy guidelines. ► The proposed index shows an important correlation with indoor thermal comfort international index DH. -- Abstract: Buildings’ thermal-energetic assessment and the relative proposal of new technical solutions applied to both summer and winter analyses has a strategic role in increasing the year-round performance of buildings. Buildings’ dynamic analysis is by now a well-established procedure to study effective building energy performance given real climate considerations. Then in this work, a concise and effective methodology for analyzing buildings’ thermal performance in a dynamic environment is proposed and applied to different case studies, consisting of single-family residential buildings’ prototypes. This procedure is aimed to define different performance levels by proper non-dimensional indexes named thermal deviation indexes (TDI). These indexes values could express in a concise way buildings’ thermal behavior, different optimization strategies impact, sensitivity analysis results. Buildings’ prototypes representing the case studies are three free-floating houses where the architectural shape role and the sensitivity of different envelope features are analyzed, also supported by experimental results regarding envelope properties measured on existing residential buildings in Italy. The three prototypes are respectively designed to optimize summer or winter energy performance or to represent the typical Italian house before and after energy efficiency regulation is implemented. To better define the important envelope parameters necessary to calibrate the numerical models, experimental activities are conducted. In particular, thermal insulation level and roof

  18. A comparison of experimental methods for measuring water permeability of porous building rocks

    Directory of Open Access Journals (Sweden)

    Galvan, S.

    2014-09-01

    Full Text Available This paper compares different experimental methods for measuring water permeability in 17 different porous building rocks. Both commercial apparatus and specially made designed permeameters are used for characterising intrinsic permeability and hydraulic conductivity, k, of rocks in the range of 10−12 to 10−4 m/s (~ 10−19−10−11 m2 or ~ 10−4−104 mD. We use both falling head and constant head permeameter methods including the triaxial and modified triaxial tests and a classical constant head permeameter. Results showed that for very low and low permeability samples (k−6 m/s, triaxial conditions were found the most accurate procedures and they provided similar or slightly lower permeability values than constant and falling head methods. The latter techniques were highly recommended for permeable and high permeable porous building materials. Water permeability values were also linked to effective porosity and interpreted in terms of interparticle and vugs porosity. Finally, some modifications in the apparatus and procedures were carried out in order to assess water permeability in soft materials, which involve the use of non-saturated samples.Se comparan diferentes métodos experimentales para la medida de la permeabilidad al agua en rocas porosas usadas como material de construcción. Se usaron diferentes permeabilímetros, (comerciales y desarrollados específicamente empleando los métodos triaxial, triaxial modificado, carga constante y carga variable. Se caracterizó la permeabilidad intrínseca y conductividad hidráulica, k, con valores que var.an desde 10−12 a 10−4 m/s (~ 10−19−10−11 m2 or ~ 10−4−104 mD. Para muestras poco y muy poco permeables el ensayo con célula triaxial fue el mas reproducible. Los ensayos de carga constante son muy recomendables para rocas porosas de construcción permeables y muy permeables. Además, se definen los parámetros experimentales más apropiados para caracterizar la

  19. Improvement of mechanical properties of polymeric composites: Experimental methods and new systems

    Science.gov (United States)

    Nguyen, Felix Nhanchau

    Filler- (e.g., particulate or fiber) reinforced structural polymers or polymeric composites have changed the way things are made. Today, they are found, for example, in air/ground transportation vehicles, sporting goods, ballistic barrier applications and weapons, electronic packaging, musical instruments, fashion items, and more. As the demand increases, so does the desire to have not only well balanced mechanical properties, but also light weight and low cost. This leads to a constant search for novel constituents and additives, new fabrication methods and analytical techniques. To achieve new or improved composite materials requires more than the identification of the right reinforcements to be used with the right polymer matrix at the right loading. Also, an optimized adhesion between the two phases and a toughened matrix system are needed. This calls for new methods to predict, modify and assess the level of adhesion, and new developments in matrix tougheners to minimize compromises in other mechanical/thermal properties. Furthermore, structural optimization, associated with fabrication (e.g., avoidance of fiber-fiber touching or particle aggregation), and sometimes special properties, such as electrical conductivity or magnetic susceptibility are necessary. Finally, the composite system's durability, often under hostile conditions, is generally mandatory. The present study researches new predictive and experimental methods for optimizing and characterizing filler-matrix adhesion and develops a new type of epoxy tougheners. Specifically, (1) a simple thermodynamic parameter evaluated by UNIFAC is applied successfully to screen out candidate adhesion promoters, which is necessary for optimization of the physio-chemical interactions between the two phases; (2) an optical-acoustical mechanical test assisted with an acoustic emission technique is developed to de-convolute filler debonding/delamination among many other micro failure events, and (3) novel core

  20. Acquiring molecular interference functions of X-ray coherent scattering for breast tissues by combination of simulation and experimental methods

    International Nuclear Information System (INIS)

    Chaparian, A.; Oghabian, M. A.; Changizi, V.

    2009-01-01

    Recently, it has been indicated that X-ray coherent scatter from biological tissues can be used to access signature of tissue. Some scientists are interested in studying this effect to get early detection of breast cancer. Since experimental methods for optimization are time consuming and expensive, some scientists suggest using simulation. Monte Carlo codes are the best option for radiation simulation: however, one permanent defect with Monte Carlo codes has been the lack of a sufficient physical model for coherent (Rayleigh) scattering, including molecular interference effects. Materials and Methods: It was decided to obtain molecular interference functions of coherent X-ray scattering for normal breast tissues by combination of modeling and experimental methods. A Monte Carlo simulation program was written to simulate the angular distribution of scattered photons for the normal breast tissue samples. Moreover, experimental diffraction patterns of these tissues were measured by means of energy dispersive X-ray diffraction method. The simulation and experimental data were used to obtain a tabulation of molecular interference functions for breast tissues. Results: With this study a tabulation of molecular interference functions for normal breast tissues Was prepared to facilitate the simulation diffraction patterns of the tissues without any experimental. Conclusion: The method may lead to design new systems for early detection of breast cancer.

  1. Calculating the parameters of experimental data Gauss distribution using the least square fit method and evaluation of their accuracy

    International Nuclear Information System (INIS)

    Guseva, E.V.; Peregudov, V.N.

    1982-01-01

    The FITGAV program for calculation of parameters of the Gauss curve describing experimental data is considered. The calculations are based on the least square fit method. The estimations of errors in the parameter determination as a function of experimental data sample volume and their statistical significance are obtained. The curve fit using 100 points occupies less than 1 s at the SM-4 type computer

  2. Incremental elongation or ratchetting - Experimental tests and practical method of analysis (on stainless steel 304L and 306L)

    International Nuclear Information System (INIS)

    Cousseran, Pierre; Lebey, Jacques; Roche, Roland; Clement, Gerard; Moulin, Didier.

    1980-12-01

    Ratchetting, or incremental elongation can be considered as a creep enhancement when cyclic deformations are added to a primary constant load. Under examination, it appears that theoretical models proposed till now do not fit correctly the actual behavior of materials. From experimental tests results performed in Saclay, a simplified method for prevention of ratcheting is proposed. A validation was made by using experimental data from various sources [fr

  3. Experimental research on application of mutual-aid teaching method in technique teaching of university’s football elective course

    Directory of Open Access Journals (Sweden)

    Wu Jiarong

    2016-01-01

    Full Text Available With the social development and reform of education system, the quality-oriented education and lifelong education gradually become education reform goals of colleges and universities, the physical education of the higher education and university are also developed. This research adopts the literature data method, ques-tionnaire method, experimental method, mathematical statistics or other methods to do experiments for the stu-dents who take the football elective course (a total of 36 class hours per semester in Zhuhai College of Jilin University with the mutual-aid teaching method. The experimental results show that: First, there is a significant difference between achievements of the specific football technique of the students in the experimental group and the students in the control group (P <0.05; second, in the teaching evaluation, the failure rate of the students in the experimental group significantly reduces, and the pass rate and good rate significantly increases after experi-ment; third, the majority of students accept the mutual-aid teaching method; fourth, the mutual-aid teaching method can be used to significantly improve the learning motivation level of the students.

  4. Numerical and experimental evaluation of masonry prisms by finite element method

    Directory of Open Access Journals (Sweden)

    C. F.R. SANTOS

    Full Text Available Abstract This work developed experimental tests and numerical models able to represent the mechanical behavior of prisms made of ordinary and high strength concrete blocks. Experimental tests of prisms were performed and a detailed micro-modeling strategy was adopted for numerical analysis. In this modeling technique, each material (block and mortar was represented by its own mechanical properties. The validation of numerical models was based on experimental results. It was found that the obtained numerical values of compressive strength and modulus of elasticity differ by 5% from the experimentally observed values. Moreover, mechanisms responsible for the rupture of the prisms were evaluated and compared to the behaviors observed in the tests and those described in the literature. Through experimental results it is possible to conclude that the numerical models have been able to represent both the mechanical properties and the mechanisms responsible for failure.

  5. Longitudinal bunch diagnostics using coherent transition radiation spectroscopy. Physical principles, multichannel spectrometer, experimental results, mathematical methods

    International Nuclear Information System (INIS)

    Schmidt, Bernhard; Wesch, Stephan; Behrens, Christopher; Koevener, Toke; Hass, Eugen; Casalbuoni, Sara

    2018-03-01

    The generation and properties of transition radiation (TR) are thoroughly treated. The spectral energy density, as described by the Ginzburg-Frank formula, is computed analytically, and the modifications caused by the finite size of the TR screen and by near-field diffraction effects are carefully analyzed. The principles of electron bunch shape reconstruction using coherent transition radiation are outlined. Spectroscopic measurements yield only the magnitude of the longitudinal form factor but not its phase. Two phase retrieval methods are investigated and illustrated with model calculations: analytic phase computation by means of the Kramers-Kronig dispersion relation, and iterative phase retrieval. Particular attention is paid to the ambiguities which are unavoidable in the reconstruction of longitudinal charge density profiles from spectroscopic data. The origin of these ambiguities has been identified and a thorough mathematical analysis is presented. The experimental part of the paper comprises a description of our multichannel infrared and THz spectrometer and a selection of measurements at FLASH, comparing the bunch profiles derived from spectroscopic data with those determined with a transversely deflecting microwave structure. A rigorous derivation of the Kramers-Kronig phase formula is presented in Appendix A. Numerous analytic model calculations can be found in Appendix B. The differences between normal and truncated Gaussians are discussed in Appendix C. Finally, Appendix D contains a short description of the propagation of an electromagnetic wave front by two-dimensional fast Fourier transformation. This is the basis of a powerful numerical Mathematica trademark code THzTransport, which permits the propagation of electromagnetic wave fronts through a beam line consisting of drift spaces, lenses, mirrors and apertures.

  6. Using tracer methods and experimental design approach for examination of hydrodynamic conditions in membrane separation modules

    Energy Technology Data Exchange (ETDEWEB)

    Miskiewicz, Agnieszka, E-mail: a.miskiewicz@ichtj.waw.pl [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Zakrzewska-Trznadel, Grazyna; Dobrowolski, Andrzej; Jaworska-Sobczak, Agnieszka [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland)

    2012-05-15

    The possibility of application of fluorescein and radioactive 99mTc as tracers for determination of residence time distribution of liquid phase and for diagnosing hydrodynamic conditions in apparatuses for membrane separation was studied. Two different ultrafiltration systems with diverse arrangement of liquid flow: the apparatus with helical flow generated by the movable element (inner cylinder) and the tubular module with cross flow filtration, were tested by the RTD technique. The tracer studies were supplemented with modelling. The optimal conditions enabling to handle the plug flow-like structure in the helical apparatus were determined. The minimum of dimensionless variance (vard) was obtained at P=0.765 bar, Q{sub R}=121.88 l/h and {Omega}=2887.5 rpm. In spite of higher linear velocities attained in the tubular cross-flow module, the flow structure in the helical apparatus was more similar to the ideal plug flow pattern that was demonstrated by higher Peclet numbers and lower values of the dimensionless variance. Application of movable part and Couette-Taylor flow in the membrane apparatus may balance the advantages coming from high flow rates applied in cross-flow filtration systems minimising formation of the deposit on the membrane surface and reducing membrane fouling. - Highlights: Black-Right-Pointing-Pointer Application of RTD method with modelling for testing the membrane modules. Black-Right-Pointing-Pointer The use of generator isotope, as convenient tracer for the membrane modules studies. Black-Right-Pointing-Pointer Application of RSM with experimental design for testing interactions between parameters. Black-Right-Pointing-Pointer Assessment of the hydrodynamic conditions in two arrangements of the membrane modules. Black-Right-Pointing-Pointer Demonstration of the advantage of dynamic filtration over the cross-flow arrangement.

  7. Longitudinal bunch diagnostics using coherent transition radiation spectroscopy. Physical principles, multichannel spectrometer, experimental results, mathematical methods

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Bernhard; Wesch, Stephan; Behrens, Christopher [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Koevener, Toke [Hamburg Univ. (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Hass, Eugen [Hamburg Univ. (Germany); Casalbuoni, Sara [Karlsruhe Institute of Technology (Germany). Inst. for Beam Physics and Technology; Schmueser, Peter [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Hamburg Univ. (Germany)

    2018-03-15

    The generation and properties of transition radiation (TR) are thoroughly treated. The spectral energy density, as described by the Ginzburg-Frank formula, is computed analytically, and the modifications caused by the finite size of the TR screen and by near-field diffraction effects are carefully analyzed. The principles of electron bunch shape reconstruction using coherent transition radiation are outlined. Spectroscopic measurements yield only the magnitude of the longitudinal form factor but not its phase. Two phase retrieval methods are investigated and illustrated with model calculations: analytic phase computation by means of the Kramers-Kronig dispersion relation, and iterative phase retrieval. Particular attention is paid to the ambiguities which are unavoidable in the reconstruction of longitudinal charge density profiles from spectroscopic data. The origin of these ambiguities has been identified and a thorough mathematical analysis is presented. The experimental part of the paper comprises a description of our multichannel infrared and THz spectrometer and a selection of measurements at FLASH, comparing the bunch profiles derived from spectroscopic data with those determined with a transversely deflecting microwave structure. A rigorous derivation of the Kramers-Kronig phase formula is presented in Appendix A. Numerous analytic model calculations can be found in Appendix B. The differences between normal and truncated Gaussians are discussed in Appendix C. Finally, Appendix D contains a short description of the propagation of an electromagnetic wave front by two-dimensional fast Fourier transformation. This is the basis of a powerful numerical Mathematica trademark code THzTransport, which permits the propagation of electromagnetic wave fronts through a beam line consisting of drift spaces, lenses, mirrors and apertures.

  8. Crack identification method in beam-like structures using changes in experimentally measured frequencies and Particle Swarm Optimization

    Science.gov (United States)

    Khatir, Samir; Dekemele, Kevin; Loccufier, Mia; Khatir, Tawfiq; Abdel Wahab, Magd

    2018-02-01

    In this paper, a technique is presented for the detection and localization of an open crack in beam-like structures using experimentally measured natural frequencies and the Particle Swarm Optimization (PSO) method. The technique considers the variation in local flexibility near the crack. The natural frequencies of a cracked beam are determined experimentally and numerically using the Finite Element Method (FEM). The optimization algorithm is programmed in MATLAB. The algorithm is used to estimate the location and severity of a crack by minimizing the differences between measured and calculated frequencies. The method is verified using experimentally measured data on a cantilever steel beam. The Fourier transform is adopted to improve the frequency resolution. The results demonstrate the good accuracy of the proposed technique.

  9. The experimental learning method for environmental education (Tamet in students from the National University of Central Perú

    Directory of Open Access Journals (Sweden)

    Rosa Haydeé Zárate Quiñones

    2016-06-01

    Full Text Available This research was conducted in order to apply the experimental method of learning for Sustainable Development in students of the Faculty of Forestry and Environmental Sciences of the National University of Central Peru. For its development we worked with a sample of 1062 students and a quasi-experimental design was used. Were employed different methods of mathematical theoretical, empirical and statistical level that allowed data collection, analysis and interpretation of results. A test of knowledge in Environmental Education for Sustainable Development to students, a questionnaire of perception and opinion, as well as a questionnaire of teacher training was applied. The experimental method used allowed the development of knowledge, habits and environmental values for sustainable development in students, contributing to the protection and conservation of the environment.

  10. Experimental substantiation of separation techniques of lead and uranium microamounts using isotopic dilution method as control method

    International Nuclear Information System (INIS)

    Agapova, A.A.; Shcherbinina, N.K.

    1983-01-01

    Methods,ensuring at low levels of contamination a high degree of lead and uranium microamount separation from solutions of geological samples, have been selected and subjected to the detailed testing. The method of isotope dilution, , combining high accuracy and sensitivity of determinations, is used as the main control methods, is used as the main control method. Using the method, processe es of uranium extpaction are traced, special attention is paid to the detailed description of lead extraction at all the stages of the methods selected. Opera ations of ion exchange for lead and uranium in microcolumns with the Bio-Rad r sin are considered, as well as operations of lead electrolytic separation. The chemical procedures suggested permit to solve one of the main methodical tasks f sample preparation, containing microgram amounts of lead and uranium, for high h-prcision measurement of their isotope composition using mass-spectrometric method

  11. Experimental evaluation of neural probe’s insertion induced injury based on digital image correlation method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wenguang, E-mail: zhwg@sjtu.edu.cn; Ma, Yakun; Li, Zhengwei [State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2016-01-15

    Purpose: The application of neural probes in clinic has been challenged by probes’ short lifetime when implanted into brain tissue. The primary goal is to develop an evaluation system for testing brain tissue injury induced by neural probe’s insertion using microscope based digital image correlation method. Methods: A brain tissue phantom made of silicone rubber with speckle pattern on its surface was fabricated. To obtain the optimal speckle pattern, mean intensity gradient parameter was used for quality assessment. The designed testing system consists of three modules: (a) load module for simulating neural electrode implantation process; (b) data acquisition module to capture micrographs of speckle pattern and to obtain reactive forces during the insertion of the probe; (c) postprocessing module for extracting tissue deformation information from the captured speckle patterns. On the basis of the evaluation system, the effects of probe wedge angle, insertion speed, and probe streamline on insertion induced tissue injury were investigated. Results: The optimal quality speckle pattern can be attained by the following fabrication parameters: spin coating rate—1000 r/min, silicone rubber component A: silicone rubber component B: softener: graphite = 5 ml: 5 ml: 2 ml: 0.6 g. The probe wedge angle has a significant effect on tissue injury. Compared to wedge angle 40° and 20°, maximum principal strain of 60° wedge angle was increased by 40.3% and 87.5%, respectively; compared with a relatively higher speed (500 μm/s), the maximum principle strain within the tissue induced by slow insertion speed (100 μm/s) was increased by 14.3%; insertion force required by probe with convex streamline was smaller than the force of traditional probe. Based on the experimental results, a novel neural probe that has a rounded tip covered by a biodegradable silk protein coating with convex streamline was proposed, which has both lower insertion and micromotion induced tissue

  12. Characterisation of the glass transition of an amorphous drug using modulated DSC.

    Science.gov (United States)

    Royall, P G; Craig, D Q; Doherty, C

    1998-07-01

    The use of modulated differential scanning calorimetry (MDSC) as a novel means of characterising the glass transition of amorphous drugs has been investigated, using the protease inhibitor saquinavir as a model compound. In particular, the effects of measuring variables (temperature cycling, scanning period, heating mode) have been examined. Saquinavir samples of known moisture content were examined using a TA Instruments 2920 MDSC at a heating rate of 2 degrees C/min and an amplitude of +/-0.159 degrees C with a period of 30 seconds. These conditions were used to examine the effects of cycling between - 50 degrees C and 150 degrees C. A range of periods between 20 and 50 seconds were then studied. Isothermal measurements were carried out between 85 degrees C and 120 degrees C using an amplitude of +/-0.159 degrees C with a period of 30 seconds. MDSC showed the glass transition of saquinavir (0.98 +/- 0.05%w/w moisture content) in isolation from the relaxation endotherm to give an apparent glass transition temperature of 107.0 degrees C +/- 0.4 degrees C. Subsequent temperature cycling gave reproducible glass transition temperatures of approximately 105 degrees C for both cooling and heating cycles. The enthalpic relaxation peak observed in the initial heating cycle had an additional contribution from a Tg "shift" effect brought about by the difference in response to the glass transition of the total and reversing heat flow signals. Isothermal studies yield a glass transition at 105.9 degrees C +/- 0.1 degrees C. MDSC has been shown to be capable of separating the glass transition of saquinavir from the relaxation endotherm, thereby facilitating measurement of this parameter without the need for temperature cycling. However, the Tg "shift" effect and the number of modulations through the transition should be taken into account to avoid drawing erroneous conclusions from the experimental data. MDSC has been shown to be an effective method of characterising the glass

  13. Radiometric method for the characterization of particulate processes in colloidal suspensions. II. Experimental verification of the method

    Energy Technology Data Exchange (ETDEWEB)

    Subotic, B. [Institut Rudjer Boskovic, Zagreb (Yugoslavia)

    1979-09-15

    A radiometric method for the characterization of particulate processes is verified using stable hydrosols of silver iodide. Silver iodide hydrosols satisfy the conditions required for the applications of the proposed method. Comparison shows that the values for the change of particle size measured in silver iodide hydrosols by the proposed method are in excellent agreement with the values obtained by other methods on the same systems (electron microscopy, sedimentation analysis, light scattering). This shows that the proposed method is suitable for the characterization of particulate processes in colloidal suspensions. (Auth.).

  14. Exploration of a new method in determining the glass transition temperature of BMGs by electrical resistivity

    Science.gov (United States)

    Guo, Jing; Zu, Fangqiu; Chen, Zhihao; Zheng, Shubin; Yuan, Yuan

    2005-07-01

    Based on a brief retrospect of the method in establishing Tg of the bulk metallic glasses (BMGs), some perplexities concerning this are pointed out. With the experimental results of Zr-Al-Ni-Cu-X (Nb,Ti) BMGs, a electrical resistivity method is proposed to determine the glass transition temperature of BMGs. With the method, we define two kinds of characteristic temperature related to the glass transition, Tg-dep and Tg-int, respectively. By comparing Tg-dep and Tg-int with Tg determined by the DSC method, we have found that, for the same alloy at the same heating rate, Tg-dep is very close to Tg-onset while Tg-int is approximate to Tg-mid. As a method to determine the glass transition temperature, the electrical resistivity method has proved to be more convenient and practical in comparison with the DSC method, especially when the DSC curve cannot show the glass transition character of BMGs. In addition, we would emphasize that when we refer to Tg, it is necessary to expatiate on the way of denoting the glass transition temperature, such as Tg-dep or Tg-int ( Tg-onset or Tg-mid), and on the heating rate, in order to avoid ambiguity.

  15. For a reasoned development of experimental methods in information and communication sciences Some epistemological findings of methodological pluralism

    Directory of Open Access Journals (Sweden)

    Didier COURBET

    2013-07-01

    Full Text Available If multidisciplinarity is necessary, first, for studying the widest possible set of communication phenomena (organizational, in groups, interpersonal, media, computer-mediated communication... and, secondly, for grasping the complexity of the different moments of the same phenomenon of communication (production, content, reception, circulation ..., methodological pluralism is also important. However, French research in communication sciences leaves in the shade a number of phenomena and moments of communication that could be better understood thanks to the experimental method. We will underline that the epistemological issues related to rational use of the experimental method in communication sciences are not negligible: it allows the study of objects that cannot be investigated with other methods and offers the opportunity to build knowledge by the refutation of hypotheses and theoretical propositions. We will clarify some epistemological misunderstandings concerning this method. First, it is actually a method of studying complex systems and communication processes. Secondly, its use is not incompatible with constructivism.

  16. El método científico experimental en las clases de laboratorio de física / The experimental scientific method in Physics laboratory lessons

    Directory of Open Access Journals (Sweden)

    Landa, L. C.

    2016-12-01

    Full Text Available En el presente estudio los autores abordan la aplicación del método científico experimental en el proceso de enseñanza de la Física como parte del modelo de aprendizaje como investigación en la carrera de Matemática-Física. El análisis de diferentes resultados investigativos publicados en la última década posibilitó identificar avances significativos en este campo, sobre todo en cuanto a la operacionalización del método y la utilización de simulaciones y experimentos virtuales en la enseñanza de la Física, sin embargo, aún persisten insuficiencias en el proceder de los docentes que limitan la apropiación del método por parte de los estudiantes. En particular, se ofrece a los docentes una alternativa metodológica para la introducción del método científico experimental, en las prácticas de laboratorio de Física, que contribuye al tránsito de los estudiantes por los procedimientos del citado método. Finalmente se expone un ejemplo concreto del modo en que se aplicó la alternativa metodológica en una clase de laboratorio de Física. This article deals with the application of the experimental scientific method in the teaching and learning process in Mathematics-Physics career as a part of learning by researching model. The study of references and the analysis of former research findings allow identifying significant achievements in the last ten years, mainly about the application of the method and also the use of virtual experiments and simulation in teaching Physics. However, there are several shortcomings of procedural nature that hinder the students’ appropriation of the method. The main finding is a proposal of a teaching alternative to achieve the learning of the experimental scientific method and its procedures by the students. Finally, that teaching alternative is illustrated in a particular Physics laboratory lesson

  17. Plant Disease Severity Assessment-How Rater Bias, Assessment Method, and Experimental Design Affect Hypothesis Testing and Resource Use Efficiency.

    Science.gov (United States)

    Chiang, Kuo-Szu; Bock, Clive H; Lee, I-Hsuan; El Jarroudi, Moussa; Delfosse, Philippe

    2016-12-01

    The effect of rater bias and assessment method on hypothesis testing was studied for representative experimental designs for plant disease assessment using balanced and unbalanced data sets. Data sets with the same number of replicate estimates for each of two treatments are termed "balanced" and those with unequal numbers of replicate estimates are termed "unbalanced". The three assessment methods considered were nearest percent estimates (NPEs), an amended 10% incremental scale, and the Horsfall-Barratt (H-B) scale. Estimates of severity of Septoria leaf blotch on leaves of winter wheat were used to develop distributions for a simulation model. The experimental designs are presented here in the context of simulation experiments which consider the optimal design for the number of specimens (individual units sampled) and the number of replicate estimates per specimen for a fixed total number of observations (total sample size for the treatments being compared). The criterion used to gauge each method was the power of the hypothesis test. As expected, at a given fixed number of observations, the balanced experimental designs invariably resulted in a higher power compared with the unbalanced designs at different disease severity means, mean differences, and variances. Based on these results, with unbiased estimates using NPE, the recommended number of replicate estimates taken per specimen is 2 (from a sample of specimens of at least 30), because this conserves resources. Furthermore, for biased estimates, an apparent difference in the power of the hypothesis test was observed between assessment methods and between experimental designs. Results indicated that, regardless of experimental design or rater bias, an amended 10% incremental scale has slightly less power compared with NPEs, and that the H-B scale is more likely than the others to cause a type II error. These results suggest that choice of assessment method, optimizing sample number and number of replicate

  18. Experimental Validation of Ex-Vessel Neutron Spectrum by Means of Dosimeter Materials Activation Method

    Directory of Open Access Journals (Sweden)

    S.A. Santa

    2017-06-01

    Full Text Available Neutron spectrum information in reactor core and around of ex-vessel reactor needs to be known with a certain degree of accuracy to support the development of fuels, materials, and other components. The most common method to determine neutron spectra is by utilizing the radioactivation of dosimeter materials. This report presents the evaluation of neutron flux incident on M3dosimeter sets which were irradiated outside the reactor vessel,as well as the validation of  neutron spectrum calculation. Al capsules containing both dosimeter set covered withCd and dosimeter set without Cd cover have been irradiated during the 35th operational cycle in the M3 ex-vessel irradiation hole position207 cmfrom core centerline at the space between the reactor vessel and the safety vessel. The capsules were positioned at Z=0.0 cm of core midplane. Each dosimeter set consists of Co-Al, Sc, Fe, Np, Nb, Ni, B, and Ta. The gamma-ray spectra of irradiated dosimeter materials were measured by 63 cc HPGe solid-state detector and photo-peak spectra were analyzed using BOB75 code. The reaction rates of each dosimeter materials and its uncertainty were analyzed based on 59Co (n,g 60Co, 237Np (n,f 95Zr-103Ru,  45Sc (n,g 46Sc, 58Fe (n,g 59Fe, 181Ta (n,g 182Ta, and 58Ni (n,p58Co reactions. The measured Cd ratios indicate that neutron spectrum at the irradiated dosimeter sets was dominated by low energy neutron. The experimental result shows that the calculated neutron spectra by DORT code at the ex-vessel positions need correction, especially in the fast neutron energy region, so as to obtain reasonable unfolding result consistent with the reaction rate measurement without any exception. Using biased DORT initial spectrum, the neutron spectrum and its integral quantity were unfolded by NEUPAC code. The result shows that total neutron flux, flux above 1.0 MeV, flux above 0.1 MeV, and the displacement rate of the dosimeter set not covered with Cd were 1.75× 1012 n cm2 s-1, 1

  19. Bridges Dynamic Parameters Identification Based On Experimental and Numerical Method Comparison in Regard with Traffic Seismicity

    Science.gov (United States)

    Krkošková, Katarína; Papán, Daniel; Papánová, Zuzana

    2017-10-01

    The technical seismicity negatively affects the environment, buildings and structures. Technical seismicity means seismic shakes caused by force impulse, random process and unnatural origin. The vibration influence on buildings is evaluated in the Eurocode 8 in Slovak Republic, however, the Slovak Technical Standard STN 73 0036 includes solution of the technical seismicity. This standard also classes bridges into the group of structures that are significant in light of the technical seismicity - the group “U”. Using the case studies analysis by FEM simulation and comparison is necessary because of brief norm evaluation of this issue. In this article, determinate dynamic parameters by experimental measuring and numerical method on two real bridges are compared. First bridge, (D201 - 00) is Scaffold Bridge on the road I/11 leading to the city of Čadca and is situated in the city of Žilina. It is eleven - span concrete road bridge. The railway is the obstacle, which this bridge spans. Second bridge (M5973 Brodno) is situated in the part of Žilina City on the road of I/11. It is concrete three - span road bridge built as box girder. The computing part includes 3D computational models of the bridges. First bridge (D201 - 00) was modelled in the software of IDA Nexis as the slab - wall model. The model outputs are natural frequencies and natural vibration modes. Second bridge (M5973 Brodno) was modelled in the software of VisualFEA. The technical seismicity corresponds with the force impulse, which was put into this model. The model outputs are vibration displacements, velocities and accelerations. The aim of the experiments was measuring of the vibration acceleration time record of bridges, and there was need to systematic placement of accelerometers. The vibration acceleration time record is important during the under - bridge train crossing, about the first bridge (D201 - 00) and the vibration acceleration time domain is important during deducing the force

  20. Diclofenac Salts. V. Examples of Polymorphism among Diclofenac Salts with Alkyl-hydroxy Amines Studied by DSC and HSM

    Directory of Open Access Journals (Sweden)

    Adamo Fini

    2010-04-01

    Full Text Available Nine diclofenac salts prepared with alkyl-hydroxy amines were analyzed for their properties to form polymorphs by DSC and HSM techniques. Thermograms of the forms prepared from water or acetone are different in most cases, suggesting frequent examples of polymorphism among these salts. Polymorph transition can be better highlighted when analysis is carried out by thermo-microscopy, which in most cases made it possible to observe the processes of melting of the metastable form and re-crystallization of the stable one. Solubility values were qualitatively related to the crystal structure of the salts and the molecular structure of the cation.

  1. DSC Studies of Retrogradation and Amylose-Lipid Complex Transition Taking Place in Gamma Irradiated Wheat Starch

    International Nuclear Information System (INIS)

    Ciesla, K.

    2006-01-01

    Degradation resulting from gamma irradiation induces decrease in order of starch granules and influences the processes occurring in starch-water system. Differential scanning calorimetry (DSC) was applied at present for studying the effect of radiation with doses of 5 - 30 kGy on amylose-lipid complex transition and retrogradation occurring in wheat starch gels. Influence of the conditions applied during DSC measurements and intermediate storage was tested on the possibility to observe radiation effect. Wheat starch was irradiated with 60 C o gamma rays in a gamma cell Issledovatiel placed in the Department of Radiation Chemistry, INCT. DSC measurements were performed for ca. 50% and ca. 20% gels during heating - cooling - heating cycles (up to 3 cycles) in the temperature range 10 - 150 degree at heating and cooling rates of 10, 5 and 2.5 degree min - 1. The Seiko DSC 6200 calorimeter was used. Decrease in amylose-lipid complex transition temperature was found already after irradiation of wheat starch with a dose of 5 kGy showing modificatin of the complex structure. The differences between the irradiated and the non-irradiated samples became the easier seen in the every foregoing heating or cooling cycle as compared to the preceeding one. It is because that thermal treatment causes decrease of transition temperature in all the irradiated samples, with no effect or increase of that temperature observed in the non-irradiated ones. Irradiation hinders retrogradation taking place in ca. 50% gels but facilitates retrogradation occurring in ca. 20 % gels. Moreover, the expanded differences between the amylose-lipid complex formed in the irradiated and non-irradiated gels result due to their recrystallisation. Storage of the gels induces decrease in the temperature of the complex transition as compared to the last cycle of the first analysis. That decrease was, however, more significant in the case of all the irradiated samples than in the case of the initial sample. In

  2. Moisture distribution in sludges based on different testing methods

    Institute of Scientific and Technical Information of China (English)

    Wenyi Deng; Xiaodong Li; Jianhua Yan; Fei Wang; Yong Chi; Kefa Cen

    2011-01-01

    Moisture distributions in municipal sewage sludge, printing and dyeing sludge and paper mill sludge were experimentally studied based on four different methods, i.e., drying test, thermogravimetric-differential thermal analysis (TG-DTA) test, thermogravimetricdifferential scanning calorimetry (TG-DSC) test and water activity test. The results indicated that the moistures in the mechanically dewatered sludges were interstitial water, surface water and bound water. The interstitial water accounted for more than 50% wet basis (wb) of the total moisture content. The bond strength of sludge moisture increased with decreasing moisture content, especially when the moisture content was lower than 50% wb. Furthermore, the comparison among the four different testing methods was presented.The drying test was advantaged by its ability to quantify free water, interstitial water, surface water and bound water; while TG-DSC test, TG-DTA test and water activity test were capable of determining the bond strength of moisture in sludge. It was found that the results from TG-DSC and TG-DTA test are more persuasive than water activity test.

  3. Development of experimental method for self-wastage behavior in sodium-water reaction. Development of test rig (SWAT-2R) and study for experimental procedure

    International Nuclear Information System (INIS)

    Abe, Yuta; Shimoyama, Kazuhito; Kurihara, Akikazu

    2014-07-01

    In case of water leak from a penetrated crack on a tube of steam generator in the sodium cooled fast reactor (SFR), self-wastage, that increases the size of leak, may take place by corrosion related to chemical reaction between sodium and water. If the self-wastage continues in a certain period of time, the intact tube bundle may be damaged as a result of enlarged leak. For the safety evaluation of the accident, JAEA has been developing the analytical method of self-wastage using the multi-dimensional sodium-water reaction code. Experiments conducted so far used mainly crack-type test pieces. However, reproducibility was limited and it was difficult to evaluate individual effects of the phenomena in detail. This report describes the development of new experimental rig (SWAT-2R). SWAT-2R enables to examine corrosion effecting factors that were ambiguous in the previous studies. The report includes description of development of micro-leak test piece, examination of experimental procedure. The results will provide fundamental data for validation of the self-wastage analytical method. (author)

  4. Assessing incentive contracts for reducing residential electricity consumption: new experimental methods for new results

    International Nuclear Information System (INIS)

    Frachet, Laure

    2013-01-01

    Facing economic, political and environmental stakes, electricity providers are nowadays developing incentive tools, in order to reduce consumer's demand, particularly during peak demand periods. For residential customers, these tools can be tariffs (dynamic pricing of time-of-use tariffs), or informative devices or services (feedbacks on historical or real-time consumption, given on various media). They might go along with automation systems that can help cutting of some electric devices when needed. In order to evaluate the capacity of these settings among their customers, electricity utilities are developing quite a few studies, which are mainly field experiment often called pilots. During these pilots, demand response tools are implemented on a population sample. These long and expensive studies lid to quantitative and qualitative analysis. We have compiled about 40 of them and extract from this survey some generalizable teachings. We have shown what these results were and highlighted pilot programs' methodological limits. In order to propose a substitute to these heavy experimentations, we assessed the capacity or experimental economics. This relatively new discipline's objective is to evaluation the efficiency of institutions, like markets, but also to study what animate economic agents' behaviour, e.g. preferences, beliefs, cognitive biases, willingness to pay... We were also able to elaborate an experimental protocol dedicated to the evaluation of some demand response contracts' acceptability. The results collected during 14 experimental sessions gave us some innovative clues and insight on these contracts acceptability. But, beyond these results, we have demonstrated that even if experimental economics can't obviously be a substitute for field experiments, it can represent an interesting exploratory methodology. To sum up the experimental economics can take part of residential customers' behaviour understanding, performing

  5. Experimental Quasi-Microwave Whole-Body Averaged SAR Estimation Method Using Cylindrical-External Field Scanning

    OpenAIRE

    Kawamura, Yoshifumi; Hikage, Takashi; Nojima, Toshio

    2010-01-01

    The aim of this study is to develop a new whole-body averaged specific absorption rate (SAR) estimation method based on the external-cylindrical field scanning technique. This technique is adopted with the goal of simplifying the dosimetry estimation of human phantoms that have different postures or sizes. An experimental scaled model system is constructed. In order to examine the validity of the proposed method for realistic human models, we discuss the pros and cons of measurements and nume...

  6. A method for the experimental determination of surface photoemission core-level shifts for 3d transition metals

    NARCIS (Netherlands)

    Shamsutdinov, N.R.; Sloof, W.G.; Böttger, A.J.

    2005-01-01

    A method is presented to determine the photoelectron surface core-level shift (SCLS) of 3d transition metals using x-ray photoelectron spectroscopy. The experimental difficulties arising from the relatively large broadening of photoemission lines in the 3d transition series can be overcome by the

  7. Electrical stunning of farmed Atlantic cod Gadus morhua L.: a comparison of an industrial and experimental method

    NARCIS (Netherlands)

    Digre, H.; Erikson, U.; Misimi, E.; Lambooij, E.; Vis, van de J.W.

    2010-01-01

    An industrial and experimental electrical method for stunning farmed Atlantic cod in air and seawater (SW), respectively, were compared. The impacts of sedation with AQUI-S™ and exercise to exhaustion before electrical stunning were also assessed to monitor the possible depletion of rested muscle

  8. Experimental micro mechanics methods for conventional and negative Poisson's ratio cellular solids as Cosserat continua

    Science.gov (United States)

    Lakes, R.

    1991-01-01

    Continuum representations of micromechanical phenomena in structured materials are described, with emphasis on cellular solids. These phenomena are interpreted in light of Cosserat elasticity, a generalized continuum theory which admits degrees of freedom not present in classical elasticity. These are the rotation of points in the material, and a couple per unit area or couple stress. Experimental work in this area is reviewed, and other interpretation schemes are discussed. The applicability of Cosserat elasticity to cellular solids and fibrous composite materials is considered as is the application of related generalized continuum theories. New experimental results are presented for foam materials with negative Poisson's ratios.

  9. Combining Diffusion Tensor Metrics and DSC Perfusion Imaging: Can It Improve the Diagnostic Accuracy in Differentiating Tumefactive Demyelination from High-Grade Glioma?

    Science.gov (United States)

    Hiremath, S B; Muraleedharan, A; Kumar, S; Nagesh, C; Kesavadas, C; Abraham, M; Kapilamoorthy, T R; Thomas, B

    2017-04-01

    Tumefactive demyelinating lesions with atypical features can mimic high-grade gliomas on conventional imaging sequences. The aim of this study was to assess the role of conventional imaging, DTI metrics ( p:q tensor decomposition), and DSC perfusion in differentiating tumefactive demyelinating lesions and high-grade gliomas. Fourteen patients with tumefactive demyelinating lesions and 21 patients with high-grade gliomas underwent brain MR imaging with conventional, DTI, and DSC perfusion imaging. Imaging sequences were assessed for differentiation of the lesions. DTI metrics in the enhancing areas and perilesional hyperintensity were obtained by ROI analysis, and the relative CBV values in enhancing areas were calculated on DSC perfusion imaging. Conventional imaging sequences had a sensitivity of 80.9% and specificity of 57.1% in differentiating high-grade gliomas ( P = .049) from tumefactive demyelinating lesions. DTI metrics ( p : q tensor decomposition) and DSC perfusion demonstrated a statistically significant difference in the mean values of ADC, the isotropic component of the diffusion tensor, the anisotropic component of the diffusion tensor, the total magnitude of the diffusion tensor, and rCBV among enhancing portions in tumefactive demyelinating lesions and high-grade gliomas ( P ≤ .02), with the highest specificity for ADC, the anisotropic component of the diffusion tensor, and relative CBV (92.9%). Mean fractional anisotropy values showed no significant statistical difference between tumefactive demyelinating lesions and high-grade gliomas. The combination of DTI and DSC parameters improved the diagnostic accuracy (area under the curve = 0.901). Addition of a heterogeneous enhancement pattern to DTI and DSC parameters improved it further (area under the curve = 0.966). The sensitivity increased from 71.4% to 85.7% after the addition of the enhancement pattern. DTI and DSC perfusion add profoundly to conventional imaging in differentiating tumefactive

  10. Experimental Design and Methods for Development of Diagnostic Assays for Schistosomiasis Using Monoclonal Antibodies.

    Science.gov (United States)

    1983-08-25

    solium, Echinococcus granulosus , Entamoeba histolytica, or Wucher erTra-bancr--ofti. The S. mansoni glycoproteins that were immunoprecipitated by sera...Sera from patients or experimental animals infected with Schistosoma, Fasciola hepatica, Trichinella spiralis, Taenia solium, Echinococcus ... granulosus , or Paragonimus westermani cross-react in diag-nostic assays with antigens derived from schistosomes, whether as whole organisms (1-4), crude

  11. Experimental investigation of in-cylinder wall wetting in GDI engines using a shadowgraphy method

    NARCIS (Netherlands)

    Luijten, B.; Adomeit, P.; Brunn, A.; Somers, L.M.T.

    2013-01-01

    This paper discusses an experimental approach to compare the amount of gasoline on the liner for different engine setups. This is done in a non-fired motored gasoline direct injection (GDI) test engine with transparent liner walls. The main goal is a planar observation and detection of the liner

  12. Return to Our Roots: Raising Radishes to Teach Experimental Design. Methods and Techniques.

    Science.gov (United States)

    Stallings, William M.

    1993-01-01

    Reviews research in teaching applied statistics. Concludes that students should analyze data from studies they have designed and conducted. Describes an activity in which students study germination and growth of radish seeds. Includes a table providing student instructions for both the experimental procedure and data analysis. (CFR)

  13. Guided-Inquiry Labs Using Bean Beetles for Teaching the Scientific Method & Experimental Design

    Science.gov (United States)

    Schlueter, Mark A.; D'Costa, Allison R.

    2013-01-01

    Guided-inquiry lab activities with bean beetles ("Callosobruchus maculatus") teach students how to develop hypotheses, design experiments, identify experimental variables, collect and interpret data, and formulate conclusions. These activities provide students with real hands-on experiences and skills that reinforce their understanding of the…

  14. Experimental validation of vibro-impact force models using numeric simulation and perturbation methods

    DEFF Research Database (Denmark)

    de Souza Reboucas, Geraldo Francisco; Santos, Ilmar; Thomsen, Jon Juel

    2017-01-01

    The frequency response of a single-degree of freedom vibro-impact oscillator is analysed using Harmonic Linearization, Averaging and Numeric Simulations considering two different impact force models, one given by a piecewise-linear function and other by a high-order polynomial. Experimental...

  15. Design of passive directional acoustic devices using Topology Optimization - from method to experimental validation

    DEFF Research Database (Denmark)

    Christiansen, Rasmus Ellebæk; Fernandez Grande, Efren

    2016-01-01

    emission in two dimensions and is experimentally validated using three dimensional prints of the optimized designs. The emitted fields exhibit a level difference of at least 15 dB on axis relative to the off-axis directions, over frequency bands of approximately an octave. It is demonstrated to be possible...

  16. Experimental methods for consideration of concrete cracking in service life design

    DEFF Research Database (Denmark)

    Pease, Bradley Justin; Geiker, Mette Rica; Stang, Henrik

    2011-01-01

    .e., concrete with cracks at start of service) and to more accurately estimate time-to-cracking due to reinforcement corrosion based on experimental measurements. This paper presents two non-destructive measurement techniques with potential to quantify the impact concrete cracks have on service life...

  17. Synchronizing chaos in an experimental chaotic pendulum using methods from linear control theory

    NARCIS (Netherlands)

    Kaart, S.; Schouten, J.C.; Bleek, van den C.M.

    1999-01-01

    Linear feedback control, specifically model predictive control (MPC), was used successfully to synchronize an experimental chaotic pendulum both on unstable periodic and aperiodic orbits. MPC enables tuning of the controller to give an optimal controller performance. That is, both the fluctuations

  18. Influence of experimental methods on crossing in magnetic force-gap hysteresis curve of HTS maglev system

    Energy Technology Data Exchange (ETDEWEB)

    Lu Yiyun, E-mail: luyiyun6666@vip.sohu.co [Luoyang Institute of Science and Technology, Luoyang, Henan 471023 (China); Qin Yujie; Dang Qiaohong [Luoyang Institute of Science and Technology, Luoyang, Henan 471023 (China); Wang Jiasu [Applied Superconductivity Laboratory, Southwest Jiaotong University, P.O. Box 152, Chengdu, Sichuan 610031 (China)

    2010-12-01

    The crossing in magnetic levitation force-gap hysteresis curve of melt high-temperature superconductor (HTS) vs. NdFeB permanent magnet (PM) was experimentally studied. One HTS bulk and PM was used in the experiments. Four experimental methods were employed combining of high/low speed of movement of PM with/without heat insulation materials (HIM) enclosed respectively. Experimental results show that crossing of the levitation force-gap curve is related to experimental methods. A crossing occurs in the magnetic force-gap curve while the PM moves approaching to and departing from the sample with high or low speed of movement without HIM enclosed. When the PM is enclosed with HIM during the measurement procedures, there is no crossing in the force-gap curve no matter high speed or low speed of movement of the PM. It was found experimentally that, with the increase of the moving speed of the PM, the maximum magnitude of levitation force of the HTS increases also. The results are interpreted based on Maxwell theories and flux flow-creep models of HTS.

  19. Time-oriented experimental design method to optimize hydrophilic matrix formulations with gelation kinetics and drug release profiles.

    Science.gov (United States)

    Shin, Sangmun; Choi, Du Hyung; Truong, Nguyen Khoa Viet; Kim, Nam Ah; Chu, Kyung Rok; Jeong, Seong Hoon

    2011-04-04

    A new experimental design methodology was developed by integrating the response surface methodology and the time series modeling. The major purposes were to identify significant factors in determining swelling and release rate from matrix tablets and their relative factor levels for optimizing the experimental responses. Properties of tablet swelling and drug release were assessed with ten factors and two default factors, a hydrophilic model drug (terazosin) and magnesium stearate, and compared with target values. The selected input control factors were arranged in a mixture simplex lattice design with 21 experimental runs. The obtained optimal settings for gelation were PEO, LH-11, Syloid, and Pharmacoat with weight ratios of 215.33 (88.50%), 5.68 (2.33%), 19.27 (7.92%), and 3.04 (1.25%), respectively. The optimal settings for drug release were PEO and citric acid with weight ratios of 191.99 (78.91%) and 51.32 (21.09%), respectively. Based on the results of matrix swelling and drug release, the optimal solutions, target values, and validation experiment results over time were similar and showed consistent patterns with very small biases. The experimental design methodology could be a very promising experimental design method to obtain maximum information with limited time and resources. It could also be very useful in formulation studies by providing a systematic and reliable screening method to characterize significant factors in the sustained release matrix tablet. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Influence of experimental methods on crossing in magnetic force-gap hysteresis curve of HTS maglev system

    International Nuclear Information System (INIS)

    Lu Yiyun; Qin Yujie; Dang Qiaohong; Wang Jiasu

    2010-01-01

    The crossing in magnetic levitation force-gap hysteresis curve of melt high-temperature superconductor (HTS) vs. NdFeB permanent magnet (PM) was experimentally studied. One HTS bulk and PM was used in the experiments. Four experimental methods were employed combining of high/low speed of movement of PM with/without heat insulation materials (HIM) enclosed respectively. Experimental results show that crossing of the levitation force-gap curve is related to experimental methods. A crossing occurs in the magnetic force-gap curve while the PM moves approaching to and departing from the sample with high or low speed of movement without HIM enclosed. When the PM is enclosed with HIM during the measurement procedures, there is no crossing in the force-gap curve no matter high speed or low speed of movement of the PM. It was found experimentally that, with the increase of the moving speed of the PM, the maximum magnitude of levitation force of the HTS increases also. The results are interpreted based on Maxwell theories and flux flow-creep models of HTS.

  1. 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

  2. ATD and DSC Analysis of IN-713C and ZhS6U-VI Superalloys

    Directory of Open Access Journals (Sweden)

    Binczyk F.

    2017-03-01

    Full Text Available Paper presents the results of ATD and DSC analysis of two superalloys used in casting of aircraft engine parts. The main aim of the research was to obtain the solidification parameters, especially Tsol and Tliq, knowledge of which is important for proper selection of casting and heat treatment parameters. Assessment of the metallurgical quality (presence of impurities of the feed ingots is also a very important step in production of castings. It was found that some of the feed ingots delivered by the superalloy producers are contaminated by oxides located in shrinkage defects. The ATD analysis allows for quite precise interpretation of first stages of solidification at which solid phases with low values of latent heat of solidification are formed from the liquid. Using DSC analysis it is possible to measure precisely the heat values accompanying the phase changes during cooling and heating which, with knowledge of phase composition, permits to calculate the enthalpy of formation of specific phases like γ or γ′.

  3. Combination of (M)DSC and surface analysis to study the phase behaviour and drug distribution of ternary solid dispersions.

    Science.gov (United States)

    Meeus, Joke; Scurr, David J; Chen, Xinyong; Amssoms, Katie; Davies, Martyn C; Roberts, Clive J; Van den Mooter, Guy

    2015-04-01

    Miscibility of the different compounds that make up a solid dispersion based formulation play a crucial role in the drug release profile and physical stability of the solid dispersion as it defines the phase behaviour of the dispersion. The standard technique to obtain information on phase behaviour of a sample is (modulated) differential scanning calorimetry ((M)DSC). However, for ternary mixtures (M)DSC alone is not sufficient to characterize their phase behaviour and to gain insight into the distribution of the active pharmaceutical ingredient (API) in a two-phased polymeric matrix. MDSC was combined with complementary surface analysis techniques, specifically time-of-flight secondary ion mass spectrometry (ToF-SIMS) and atomic force microscopy (AFM). Three spray-dried model formulations with varying API/PLGA/PVP ratios were analyzed. MDSC, TOF-SIMS and AFM provided insights into differences in drug distribution via the observed surface coverage for 3 differently composed ternary solid dispersions. Combining MDSC and surface analysis rendered additional insights in the composition of mixed phases in complex systems, like ternary solid dispersions.

  4. DSC and EPR investigations on effects of cholesterol component on molecular interactions between paclitaxel and phospholipid within lipid bilayer membrane.

    Science.gov (United States)

    Zhao, Lingyun; Feng, Si-Shen; Kocherginsky, Nikolai; Kostetski, Iouri

    2007-06-29

    Differential scanning calorimetry (DSC) and electron paramagnetic resonance spectroscopy (EPR) were applied to investigate effects of cholesterol component on molecular interactions between paclitaxel, which is one of the best antineoplastic agents found from nature, and dipalmitoylphosphatidylcholine (DPPC) within lipid bilayer vesicles (liposomes), which could also be used as a model cell membrane. DSC analysis showed that incorporation of paclitaxel into the DPPC bilayer causes a reduction in the cooperativity of bilayer phase transition, leading to a looser and more flexible bilayer structure. Including cholesterol component in the DPPC/paclitaxel mixed bilayer can facilitate the molecular interaction between paclitaxel and lipid and make the tertiary system more stable. EPR analysis demonstrated that both of paclitaxel and cholesterol have fluidization effect on the DPPC bilayer membranes although cholesterol has more significant effect than paclitaxel does. The reduction kinetics of nitroxides by ascorbic acid showed that paclitaxel can inhibit the reaction by blocking the diffusion of either the ascorbic acid or nitroxide molecules since the reaction is tested to be a first order one. Cholesterol can remarkably increase the reduction reaction speed. This research may provide useful information for optimizing liposomal formulation of the drug as well as for understanding the pharmacology of paclitaxel.

  5. Experimental comparison of phase retrieval methods which use intensity distribution at different planes

    International Nuclear Information System (INIS)

    Shevkunov, I A; Petrov, N V

    2014-01-01

    Performance of the three phase retrieval methods that use spatial intensity distributions was investigated in dealing with a task of reconstruction of the amplitude characteristics of the test object. These methods differ both by mathematical models and order of iteration execution. The single-beam multiple-intensity reconstruction method showed the best efficiency in terms of quality of reconstruction and time consumption.

  6. Relaxation dynamics of glass transition in PMMA + SWCNT composites by temperature-modulated DSC

    Science.gov (United States)

    Pradhan, N. R.; Iannacchione, G. S.

    2010-03-01

    The experimental technique offered by temperature-modulated differential scanning calorimeter (TMDSC) used to investigate the thermal relaxation dynamics through the glass transition as a function of frequency was studied for pure PMMA and PMMA-single wall carbon nanotubes (SWCNTs) composites. A strong dependence of the temperature dependence peak in the imaginary part of complex heat capacity (Tmax) is found during the transition from the glass-like to the liquid-like region. The frequency dependence of Tmax of the imaginary part of heat capacity (Cp) is described by Arrhenius law. The activation energy obtained from the fitting shows increases while the characteristic relaxation time decreases with increasing mass fraction (phim) of SWCNTs. The dynamics of the composites during glass transition, at slow and high scan rates, are also the main focus of this experimental study. The change in enthalpy during heating and cooling is also reported as a function of scan rate and frequency of temperature modulation. The glass transition temperature (Tg) shows increases with increasing frequency of temperature modulation and phim of SWCNTs inside the polymer host. Experimental results show that Tg is higher at higher scan rates but as the frequency of temperature modulation increases, the Tg values of different scan rates coincide with each other and alter the scan rate dependence. From the imaginary part of heat capacity, it is obvious that Tmax is not the actual glass transition temperature of pure polymer but Tmax and Tg values can be superimposed when phim increases in the polymer host or when the sample undergoes a transition with a certain frequency of temperature modulation.

  7. The experimental method of measurement for spatial distribution of full aperture backscatter light by circular PIN-array

    International Nuclear Information System (INIS)

    Zhao Xuefeng; Wang Chuanke; Hu Feng; Kuang Longyu; Wang Zhebin; Li Sanwei; Liu Shengye; Jiang Gang

    2011-01-01

    The spatial distribution of backscatter light is very important for understanding the production of backscatter light. The experimental method of spatial distribution of full aperture backscatter light is based on the circular PIN array composed of concentric orbicular multi-PIN detectors. The image of backscatter light spatial distribution of full aperture SBS is obtained by measuring spatial distribution of full aperture backscatter light using the method in the experiment of laser hohlraum targets interaction at 'Shenguang II'. A preliminary method to measure spatial distribution of full aperture backscatter light is established. (authors)

  8. Methods and benefits of experimental seismic evaluation of nuclear power plants. Final report

    International Nuclear Information System (INIS)

    1979-07-01

    This study reviews experimental techniques, instrumentation requirements, safety considerations, and benefits of performing vibration tests on nuclear power plant containments and internal components. The emphasis is on testing to improve seismic structural models. Techniques for identification of resonant frequencies, damping, and mode shapes, are discussed. The benefits of testing with regard to increased damping and more accurate computer models are oulined. A test plan, schedule and budget are presented for a typical PWR nuclear power plant

  9. Experimental system using an active method for the measurement of low alpha emitter grades

    International Nuclear Information System (INIS)

    Bernard, P.; Cance, M.

    1986-06-01

    The diversity of waste produced in France, the limitations of passive neutron measurements, the new safety requirements in the field of low level waste disposal have induced us to develop active neutron techniques. Two experimental pulsed neutron interrogation systems are described giving a sensitivity lower than 10 mg Pu 239 in 200 l drums. This project is the result of a close cooperation between the CEA, SGN and SODERN

  10. Methods and benefits of experimental seismic evaluation of nuclear power plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-01

    This study reviews experimental techniques, instrumentation requirements, safety considerations, and benefits of performing vibration tests on nuclear power plant containments and internal components. The emphasis is on testing to improve seismic structural models. Techniques for identification of resonant frequencies, damping, and mode shapes, are discussed. The benefits of testing with regard to increased damping and more accurate computer models are oulined. A test plan, schedule and budget are presented for a typical PWR nuclear power plant.

  11. Human experimental pain models: A review of standardized methods in drug development

    Directory of Open Access Journals (Sweden)

    K. Sunil kumar Reddy

    2012-01-01

    Full Text Available Human experimental pain models are essential in understanding the pain mechanisms and appear to be ideally suited to test analgesic compounds. The challenge that confronts both the clinician and the scientist is to match specific treatments to different pain-generating mechanisms and hence reach a pain treatment tailored to each individual patient. Experimental pain models offer the possibility to explore the pain system under controlled settings. Standardized stimuli of different modalities (i.e., mechanical, thermal, electrical, or chemical can be applied to the skin, muscles, and viscera for a differentiated and comprehensive assessment of various pain pathways and mechanisms. Using a multimodel-multistructure testing, the nociception arising from different body structures can be explored and modulation of specific biomarkers by new and existing analgesic drugs can be profiled. The value of human experimental pain models is to link animal and clinical pain studies, providing new possibilities for designing successful clinical trials. Spontaneous pain, the main compliant of the neuropathic patients, but currently there is no human model available that would mimic chronic pain. Therefore, current human pain models cannot replace patient studies for studying efficacy of analgesic compounds, although being helpful for proof-of-concept studies and dose finding.

  12. An experimental test of CSR theory using a globally calibrated ordination method.

    Science.gov (United States)

    Li, Yuanzhi; Shipley, Bill

    2017-01-01

    Can CSR theory, in conjunction with a recently proposed globally calibrated CSR ordination ("StrateFy"), using only three easily measured leaf traits (leaf area, specific leaf area and leaf dry matter content) predict the functional signature of herbaceous vegetation along experimentally manipulated gradients of soil fertility and disturbance? To determine this, we grew 37 herbaceous species in mixture for five years in 24 experimental mesocosms differing in factorial levels of soil resources (stress) and density-independent mortality (disturbance). We measured 16 different functional traits and then ordinated the resulting vegetation within the CSR triangle using StrateFy. We then calculated community-weighted mean (CWM) values of the competitor (CCWM), stress-tolerator (SCWM) and ruderal (RCWM) scores for each mesocosm. We found a significant increase in SCWM from low to high stress mesocosms, and an increase in RCWM from lowly to highly disturbed mesocosms. However, CCWM did not decline significantly as intensity of stress or disturbance increased, as predicted by CSR theory. This last result likely arose because our herbaceous species were relatively poor competitors in global comparisons and thus no strong competitors in our species pool were selectively favoured in low stress and low disturbed mesocosms. Variation in the 13 other traits, not used by StrateFy, largely argeed with the predictions of CSR theory. StrateFy worked surprisingly well in our experimental study except for the C-dimension. Despite loss of some precision, it has great potential applicability in future studies due to its simplicity and generality.

  13. Comparison of Experimental Methods for Estimating Matrix Diffusion Coefficients for Contaminant Transport Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Telfeyan, Katherine Christina [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ware, Stuart Douglas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Birdsell, Kay Hanson [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-06

    Diffusion cell and diffusion wafer experiments were conducted to compare methods for estimating matrix diffusion coefficients in rock core samples from Pahute Mesa at the Nevada Nuclear Security Site (NNSS). A diffusion wafer method, in which a solute diffuses out of a rock matrix that is pre-saturated with water containing the solute, is presented as a simpler alternative to the traditional through-diffusion (diffusion cell) method. Both methods yielded estimates of matrix diffusion coefficients that were within the range of values previously reported for NNSS volcanic rocks. The difference between the estimates of the two methods ranged from 14 to 30%, and there was no systematic high or low bias of one method relative to the other. From a transport modeling perspective, these differences are relatively minor when one considers that other variables (e.g., fracture apertures, fracture spacings) influence matrix diffusion to a greater degree and tend to have greater uncertainty than diffusion coefficients. For the same relative random errors in concentration measurements, the diffusion cell method yields diffusion coefficient estimates that have less uncertainty than the wafer method. However, the wafer method is easier and less costly to implement and yields estimates more quickly, thus allowing a greater number of samples to be analyzed for the same cost and time. Given the relatively good agreement between the methods, and the lack of any apparent bias between the methods, the diffusion wafer method appears to offer advantages over the diffusion cell method if better statistical representation of a given set of rock samples is desired.

  14. Comparison of experimental methods for estimating matrix diffusion coefficients for contaminant transport modeling

    Science.gov (United States)

    Telfeyan, Katherine; Ware, S. Doug; Reimus, Paul W.; Birdsell, Kay H.

    2018-02-01

    Diffusion cell and diffusion wafer experiments were conducted to compare methods for estimating effective matrix diffusion coefficients in rock core samples from Pahute Mesa at the Nevada Nuclear Security Site (NNSS). A diffusion wafer method, in which a solute diffuses out of a rock matrix that is pre-saturated with water containing the solute, is presented as a simpler alternative to the traditional through-diffusion (diffusion cell) method. Both methods yielded estimates of effective matrix diffusion coefficients that were within the range of values previously reported for NNSS volcanic rocks. The difference between the estimates of the two methods ranged from 14 to 30%, and there was no systematic high or low bias of one method relative to the other. From a transport modeling perspective, these differences are relatively minor when one considers that other variables (e.g., fracture apertures, fracture spacings) influence matrix diffusion to a greater degree and tend to have greater uncertainty than effective matrix diffusion coefficients. For the same relative random errors in concentration measurements, the diffusion cell method yields effective matrix diffusion coefficient estimates that have less uncertainty than the wafer method. However, the wafer method is easier and less costly to implement and yields estimates more quickly, thus allowing a greater number of samples to be analyzed for the same cost and time. Given the relatively good agreement between the methods, and the lack of any apparent bias between the methods, the diffusion wafer method appears to offer advantages over the diffusion cell method if better statistical representation of a given set of rock samples is desired.

  15. An innovative method for coordinate measuring machine one-dimensional self-calibration with simplified experimental process.

    Science.gov (United States)

    Fang, Cheng; Butler, David Lee

    2013-05-01

    In this paper, an innovative method for CMM (Coordinate Measuring Machine) self-calibration is proposed. In contrast to conventional CMM calibration that relies heavily on a high precision reference standard such as a laser interferometer, the proposed calibration method is based on a low-cost artefact which is fabricated with commercially available precision ball bearings. By optimizing the mathematical model and rearranging the data sampling positions, the experimental process and data analysis can be simplified. In mathematical expression, the samples can be minimized by eliminating the redundant equations among those configured by the experimental data array. The section lengths of the artefact are measured at arranged positions, with which an equation set can be configured to determine the measurement errors at the corresponding positions. With the proposed method, the equation set is short of one equation, which can be supplemented by either measuring the total length of the artefact with a higher-precision CMM or calibrating the single point error at the extreme position with a laser interferometer. In this paper, the latter is selected. With spline interpolation, the error compensation curve can be determined. To verify the proposed method, a simple calibration system was set up on a commercial CMM. Experimental results showed that with the error compensation curve uncertainty of the measurement can be reduced to 50%.

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

    Directory of Open Access Journals (Sweden)

    Havlik Jan

    2017-01-01

    Full Text Available 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.

  17. Fluorene: An extended experimental thermodynamic study

    International Nuclear Information System (INIS)

    Monte, Manuel J.S.; Pinto, Sónia P.; Lobo Ferreira, Ana I.M.C.; Amaral, Luísa M.P.F.; Freitas, Vera L.S.; Ribeiro da Silva, Maria D.M.C.

    2012-01-01

    Highlights: ► Experimental results of an extended thermodynamic study on fluorene are presented. ► Enthalpy of combustion and vapor pressures of liquid and crystalline phase were measured. ► Enthalpy of sublimation was derived from three different experimental methods. ► New values of enthalpies of sublimation and of formation of fluorene are recommended. - Abstract: This work reports new experimental thermodynamic results on fluorene. Vapor pressures of both crystalline and liquid phases were measured using a pressure gauge (capacitance diaphragm manometer) and Knudsen effusion methods over a wide temperature range (292.20 to 412.16) K yielding accurate determination of enthalpy and entropy of sublimation and of vaporization. The enthalpy of sublimation was also determined using Calvet microcalorimetry. The enthalpy of fusion was derived from vapor pressure results and from d.s.c. experiments. Static bomb calorimetry was used to determine the enthalpy of combustion of fluorene from which the standard enthalpy of formation in the crystalline phase was calculated. The enthalpy of formation in the gaseous phase was calculated combining the result derived for the crystalline phase with the enthalpy of sublimation.

  18. Experimental and numerical investigation of the flow measurement method utilized in the steam generator of HTR-PM

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shiming; Ren, Cheng; Sun, Yangfei [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China); Tu, Jiyuan [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China); School of Aerospace, Mechanical & Manufacturing Engineering, RMIT University, Melbourne, VIC 3083 (Australia); Yang, Xingtuan, E-mail: yangxt107@sina.com [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China)

    2016-08-15

    Highlights: • The flow confluence process in the steam generator is very important for HTR-PM. • The complicated flow in the unique pipeline configuration is studied by both of experimental and numerical method. • The pressure uniformity at the bottom of the model was tested to evaluate the accuracy of the experimental results. • Flow separation and the secondary flow is described for explaining the nonuniformity of the flow distribution. - Abstract: The helium flow measurement method is very important for the design of HTR-PM. Water experiments and numerical simulation with a 1/5 scaled model are conducted to investigate the flow measurement method utilized in the steam generator of HTR-PM. Pressure information at specific location of the 90° elbows with the diameter of 46.75 mm and radius ratio of 1.5 is measured to evaluate the flow rate in the riser-pipes. Pressure uniformity at the bottom of the experimental apparatus is tested to evaluate the influence of the equipment error on the final experimental results. Numerical results obtained by using the realizable k–ε model are compared with the experimental data. The results reveal that flow oscillation does not occur in the confluence system. For every single riser-pipe, the flow is stable despite the nonuniformity of the flow distribution. The average flow rates of the two pipe series show good repeatability regardless of the increases and decreases of the average velocity. In the header box, the flows out of the riser-pipes encounter with each other and finally distort the pressure distribution and the nonuniformity of the flow distribution becomes more significant along with the increasing Reynolds number.

  19. Evaluation of the modified nanoclay effect on the vulcanization of SBR through rheometric curve and DSC;Avaliacao do efeito de nanoargila modificada na vulcanizacao de SBR atraves da curva reometrica e DSC

    Energy Technology Data Exchange (ETDEWEB)

    Forte, Maria Madalena C.; Brito, Karin J.S., E-mail: mmcforte@ufrgs.b [Universidade Federal do Rio Grande do Sul (PPGEM/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Gheller Junior, Jordao [SENAI, Sao Leopoldo, RS (Brazil). Centro Tecnologico de Polimeros

    2009-07-01

    Rubber nanocomposites with nanoclays organically modified by quaternary ammonium salts may have the curing features modified significantly, since the salts may act on the rubber cure system. The aim of this work is to evaluate the influences of an organically modified montmorillonite (OMMT) on the curing reaction of an SBR (styrene butadiene rubber) with sulfur. The SBR/OMMT nanocomposites were prepared by co-coagulating SBR latex and Cloisite{sup R} 20A aqueous suspension at different nanoclay concentrations. The OMMT effect on the sulfur curing reaction was evaluated by the rheometric curve using a rheometer type RPA (Rubber Process Analyzer) and the heat of vulcanization (DELTAH{sub v}) using Differential Scanning Calorimetry (DSC). The evaluation of the clay nanolayers dispersion in the SBR matrix was accomplished by x-ray diffraction (XRD) analysis. (author)

  20. The impact of retirement on health: quasi-experimental methods using administrative data.

    Science.gov (United States)

    Horner, Elizabeth Mokyr; Cullen, Mark R

    2016-02-19

    Is retirement good or bad for health? Disentangling causality is difficult. Much of the previous quasi-experimental research on the effect of health on retirement used self-reported health and relied upon discontinuities in public retirement incentives across Europe. The current study investigated the effect of retirement on health by exploiting discontinuities in private retirement incentives to test the effect of retirement on health using a quasi-experimental study design. Secondary data (1997-2009) on a cohort of male manufacturing workers in a United States setting. Health status was determined using claims data from private insurance and Medicare. Analyses used employer-based administrative and claims data and claim data from Medicare. Widely used selection on observables models overstate the negative impact of retirement due to the endogeneity of the decision to retire. In addition, health status as measured by administrative claims data provide some advantages over the more commonly used survey items. Using an instrument and administrative health records, we find null to positive effects from retirement on all fronts, with a possible exception of increased risk for diabetes. This study provides evidence that retirement is not detrimental and may be beneficial to health for a sample of manufacturing workers. In addition, it supports previous research indicating that quasi-experimental methodologies are necessary to evaluate the relationship between retirement and health, as any selection on observable model will overstate the negative relationship of retirement on health. Further, it provides a model for how such research could be implemented in countries like the United States that do not have a strong public pension program. Finally, it demonstrates that such research need-not rely upon survey data, which has certain shortcomings and is not always available for homogenous samples.

  1. Differential scanning calorimetry method for purity determination: A case study on polycyclic aromatic hydrocarbons and chloramphenicol

    International Nuclear Information System (INIS)

    Kestens, V.; Zeleny, R.; Auclair, G.; Held, A.; Roebben, G.; Linsinger, T.P.J.

    2011-01-01

    Highlights: → Purity assessment of polycyclic aromatic hydrocarbons and chloramphenicol by DSC. → DSC results compared with traditional purity methods. → Different methods give different results, multiple method approach recommended. → DSC sensitive to impurities that have similar structures as main component. - Abstract: In this study the validity and suitability of differential scanning calorimetry (DSC) to determine the purity of selected polycyclic aromatic hydrocarbons and chloramphenicol has been investigated. The study materials were two candidate certified reference materials (CRMs), 6-methylchrysene and benzo[a]pyrene, and two different batches of commercially available highly pure chloramphenicol. The DSC results were compared with those obtained by other methods, namely gas and liquid chromatography with mass spectrometric detection, liquid chromatography with diode array detection, and quantitative nuclear magnetic resonance. The purity results obtained by these different analytical methods confirm the well-known challenges of comparing results of different method-defined measurands. In comparison with other methods, DSC has a much narrower working range. This limits the applicability of DSC as purity determination method, for instance during the assignment of the purity value of a CRM. Nevertheless, this study showed that DSC can be a powerful technique to detect impurities that are structurally very similar to the main purity component. From this point of view, and because of its good repeatability, DSC can be considered as a valuable technique to investigate the homogeneity and stability of candidate purity CRMs.

  2. On a possible method of experimental investigation of proton decay modes

    International Nuclear Information System (INIS)

    Gulkanyan, H.R.; Pogosov, V.S.; Tamanyan, A.G.

    1982-01-01

    A detector for experimental investigation of proton decay modes is described. The detector represents a multiwire high pressure gas chamber, located in an underground cavity in a rock salt layer, analogous to known underground artificial depositories of fuel gas. It allows to identify decay particles and reaction kinematics at the amount of working gas of several dozens of kilotons and more required for the proton decay detection at the half-lifetime tau > 10 33 years and investigation of decay modes at tau 33 years. The detector also permits to investigate other exotic events such as a search for fractional charge particles, neutrino oscillations

  3. Application of activation methods on the Dubna experimental transmutation set-ups.

    Science.gov (United States)

    Stoulos, S; Fragopoulou, M; Adloff, J C; Debeauvais, M; Brandt, R; Westmeier, W; Krivopustov, M; Sosnin, A; Papastefanou, C; Zamani, M; Manolopoulou, M

    2003-02-01

    High spallation neutron fluxes were produced by irradiating massive heavy targets with proton beams in the GeV range. The experiments were performed at the Dubna High Energy Laboratory using the nuclotron accelerator. Two different experimental set-ups were used to produce neutron spectra convenient for transmutation of radioactive waste by (n,x) reactions. By a theoretical analysis neutron spectra can be reproduced from activation measurements. Thermal-epithermal and fast-super-fast neutron fluxes were estimated using the 197Au, 238U (n,gamma) and (n,2n) reactions, respectively. Depleted uranium transmutation rates were also studied in both experiments.

  4. Feasibility of reactivity worth measurements by perturbation method with Caliban and Silene experimental reactors

    Energy Technology Data Exchange (ETDEWEB)

    Casoli, Pierre; Authier, Nicolas [Commissariat a l' Energie Atomique, Centre d' Etudes de Valduc, 21120 Is-Sur-Tille (France)

    2008-07-01

    Reactivity worth measurements of material samples put in the central cavities of nuclear reactors allow to test cross section nuclear databases or to extract information about the critical masses of fissile elements. Such experiments have already been completed on the Caliban and Silene experimental reactors operated by the Criticality and Neutronics Research Laboratory of Valduc (CEA, France) using the perturbation measurement technique. Calculations have been performed to prepare future experiments on new materials, such as light elements, structure materials, fission products or actinides. (authors)

  5. High-pressure fluid-phase equilibria: Experimental methods and systems investigated (2005-2008)

    DEFF Research Database (Denmark)

    Fonseca, José; Dohrn, Ralf; Peper, Stephanie

    2011-01-01

    %) have carbon dioxide as one of the components. Information on 206 pure components, 535 ternary systems of which 355 (66%) contain carbon dioxide, 163 multicomponent and complex systems, and 207 systems with hydrates is given. A continuation of the review series is planned, covering the years from 2009...... points, the solubility of high-boiling substances in supercritical fluids, the solubility of gases in liquids and the solubility (sorption) of volatile components in polymers are included. Most of experimental data in the literature has been given for binary systems. Of the 1469 binary systems, 796 (54...

  6. Experimental Research of Reliability of Plant Stress State Detection by Laser-Induced Fluorescence Method

    Directory of Open Access Journals (Sweden)

    Yury Fedotov

    2016-01-01

    Full Text Available Experimental laboratory investigations of the laser-induced fluorescence spectra of watercress and lawn grass were conducted. The fluorescence spectra were excited by YAG:Nd laser emitting at 532 nm. It was established that the influence of stress caused by mechanical damage, overwatering, and soil pollution is manifested in changes of the spectra shapes. The mean values and confidence intervals for the ratio of two fluorescence maxima near 685 and 740 nm were estimated. It is presented that the fluorescence ratio could be considered a reliable characteristic of plant stress state.

  7. The Application of Montessori Method in Learning Mathematics: An Experimental Research

    Science.gov (United States)

    Faryadi, Qais

    2017-01-01

    The prime objective of this research was to investigate whether the Montessori method of learning helped kindergarten pupils improve their mathematical proficiency, critical thinking and problem-solving skills, besides training them to be responsible learners. Quantitative, qualitative, and observational methods were employed in the investigation.…

  8. An experimental comparison of three wire beam electrode based methods for determining corrosion rates and patterns

    International Nuclear Information System (INIS)

    Tan, Y.-J.

    2005-01-01

    Laboratory experiments have been carried out to examine the advantages and limitations of three wire beam electrode (WBE) based techniques, including the noise resistance R n -WBE method, the overpotential-galvanic current method, and the galvanic current method, in determining corrosion rates and patterns. These techniques have been applied simultaneously to several selected corrosion systems of different characteristics. It has been found that the R n -WBE method has advantages over other WBE based methods when applying to WBE surfaces under uniform corrosion. However, the R n -WBE method has been found to be unsuitable for low noise level corrosion systems. It has also been found that both R n -WBE and overpotential-galvanic current methods are similarly applicable to WBE surfaces under nonuniform corrosion. However, the galvanic current method has been found to be suitable only for WBE surfaces under highly localised corrosion. Some related issues regarding R n calculation such as trend removal and its effects on corrosion mapping have also been discussed

  9. Novel organic NLO material bis(N-phenylbiguanidium(1+)) oxalate - A combined X-ray diffraction, DSC and vibrational spectroscopic study of its unique polymorphism

    Science.gov (United States)

    Matulková, Irena; Císařová, Ivana; Vaněk, Přemysl; Němec, Petr; Němec, Ivan

    2017-01-01

    Three polymorphic modifications of bis(N-phenylbiguanidium(1+)) oxalate are reported, and their characterization is discussed in this paper. The non-centrosymmetric bis(N-phenylbiguanidium(1+)) oxalate (I), which was obtained from an aqueous solution at 313 K, belongs to the monoclinic space group Cc (a = 6.2560(2) Å, b = 18.6920(3) Å, c = 18.2980(5) Å, β = 96.249(1)°, V = 2127.0(1) Å3, Z = 4, R = 0.0314 for 4738 observed reflections). The centrosymmetric bis(N-phenylbiguanidium(1+)) oxalate (II) was obtained from an aqueous solution at 298 K and belongs to the monoclinic space group P21/n (a = 6.1335(3) Å, b = 11.7862(6) Å, c = 14.5962(8) Å, β = 95.728(2)°, V = 1049.90(9) Å3, Z = 4, R = 0.0420 for 2396 observed reflections). The cooling of the centrosymmetric phase (II) leads to the formation of bis(N-phenylbiguanidium(1+)) oxalate (III) (a = 6.1083(2) Å, b = 11.3178(5) Å, c = 14.9947(5) Å, β = 93.151(2)°, V = 1035.05(8) Å3, Z = 4, R = 0.0345 for 2367 observed reflections and a temperature of 110 K), which also belongs to the monoclinic space group P21/n. The crystal structures of the three characterized phases are generally based on layers of isolated N-phenylbiguanidium(1 +) cations separated by oxalate anions and interconnected with them by several types of N-H...O hydrogen bonds. The observed phases generally differ not only in their crystal packing but also in the lengths and characteristics of their hydrogen bonds. The thermal behaviour of the prepared compounds was studied using the DSC method in the temperature range from 90 K up to a temperature near the melting point of each crystal. The bis(N-phenylbiguanidium(1+)) oxalate (II) crystals exhibit weak reversible thermal effects on the DSC curve at 147 K (heating run). Further investigation of this effect, which was assigned to the isostructural phase transformation, was performed using FTIR, Raman spectroscopy and X-ray diffraction analysis in a wide temperature range.

  10. Physicochemical characterization by AFM, FT-IR and DSC and biological assays of a promising antileishmania delivery system loaded with a natural Brazilian product.

    Science.gov (United States)

    Marquele-Oliveira, Franciane; Torres, Elina Cassia; Barud, Hernane da Silva; Zoccal, Karina Furlani; Faccioli, Lúcia Helena; Hori, Juliana I; Berretta, Andresa Aparecida

    2016-05-10

    The control and treatment of Leishmaniasis, a neglected and infectious disease affecting approximately 12 million people worldwide, are challenging. Leishmania parasites multiply intracellularly within macrophages located in deep skin and in visceral tissues, and the currently employed treatments for this disease are subject to significant drawbacks, such as resistance and toxicity. Thus, the search for new Leishmaniasis treatments is compulsory, and Ocotea duckei Vattimo, a plant-derived product from the biodiverse Brazilian flora, may be a promising new treatment for this disease. In this regard, the aim of this work was to develop and characterize a delivery system based on solid lipid nanoparticles (SLN) that contain the liposoluble lignan fraction (LF) of Ocotea duckei Vattimo, which targets the Leishmania phagolysosome of infected macrophages. LF-loaded SLNs were obtained via the hot microemulsion method, and their physical and chemical properties were comprehensively assessed using PCS, AFM, SEM, FT-IR, DSC, HPLC, kinetic drug release studies, and biological assays. The size of the developed delivery system was 218.85±14.2 nm, its zeta potential was -30 mV and its entrapment efficiency (EE%) was high (the EEs% of YAN [yangambin] and EPI-YAN [epi-yangambin] markers were 94.21±0.40% and 94.20±0.00%, respectively). Microscopy, FT-IR and DSC assays confirmed that the delivery system was nanosized and indicated a core-shell encapsulation model, which corroborated the measured kinetics of drug release. The total in vitro release rates of YAN and EPI-YAN in buffer (with sink conditions attained) were 29.6±8.3% and 34.3±8.9%, respectively, via diffusion through the cellulose acetate membrane of the SLN over a period of 4 h. After 24 h, the release rates of both markers reached approximately 45%, suggesting a sustained pattern of release. Mathematical modeling indicated that both markers, YAN and EPI-YAN, followed matrix diffusion-based release kinetics (Higuchi

  11. Dynamics of Polymorphic Transformations in Palm Oil, Palm Stearin and Palm Kernel Oil Characterized by Coupled Powder XRD-DSC.

    Science.gov (United States)

    Zaliha, Omar; Elina, Hishamuddin; Sivaruby, Kanagaratnam; Norizzah, Abd Rashid; Marangoni, Alejandro G

    2018-06-01

    The in situ polymorphic forms and thermal transitions of refined, bleached and deodorized palm oil (RBDPO), palm stearin (RBDPS) and palm kernel oil (RBDPKO) were investigated using coupled X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results indicated that the DSC onset crystallisation temperature of RBDPO was at 22.6°C, with a single reflection at 4.2Å started to appear from 23.4 to 17.1°C, and were followed by two prominent exothermic peaks at 20.1°C and 8.5°C respectively. Further cooling to -40°C leads to the further formation of a β'polymorph. Upon heating, a of β'→βtransformation was observed between 32.1 to 40.8°C, before the sample was completely melted at 43.0°C. The crystallization onset temperature of RBDPS was 44.1°C, with the appearance of the α polymorph at the same temperature as the appearance of the first sharp DSC exothermic peak. This quickly changed from α→β´ in the range 25 to 21.7°C, along with the formation of a small β peak at -40°C. Upon heating, a small XRD peak for the β polymorph was observed between 32.2 to 36.0°C, becoming a mixture of (β´+ β) between 44.0 to 52.5°C. Only the β polymorph survived further heating to 59.8°C. For RBDPKO, the crystallization onset temperature was 11.6°C, with the formation of a single sharp exothermic peak at 6.5°C corresponding to the β' polymorphic form until the temperature reached -40°C. No transformation of the polymorphic form was observed during the melting process of RBDPKO, before being completely melted at 33.2°C. This work has demonstrated the detailed dynamics of polymorphic transformations of PKO and PS, two commercially important hardstocks used widely by industry and will contribute to a greater understanding of their crystallization and melting dynamics.

  12. A comparative experimental evaluation of uncertainty estimation methods for two-component PIV

    Science.gov (United States)

    Boomsma, Aaron; Bhattacharya, Sayantan; Troolin, Dan; Pothos, Stamatios; Vlachos, Pavlos

    2016-09-01

    Uncertainty quantification in planar particle image velocimetry (PIV) measurement is critical for proper assessment of the quality and significance of reported results. New uncertainty estimation methods have been recently introduced generating interest about their applicability and utility. The present study compares and contrasts current methods, across two separate experiments and three software packages in order to provide a diversified assessment of the methods. We evaluated the performance of four uncertainty estimation methods, primary peak ratio (PPR), mutual information (MI), image matching (IM) and correlation statistics (CS). The PPR method was implemented and tested in two processing codes, using in-house open source PIV processing software (PRANA, Purdue University) and Insight4G (TSI, Inc.). The MI method was evaluated in PRANA, as was the IM method. The CS method was evaluated using DaVis (LaVision, GmbH). Utilizing two PIV systems for high and low-resolution measurements and a laser doppler velocimetry (LDV) system, data were acquired in a total of three cases: a jet flow and a cylinder in cross flow at two Reynolds numbers. LDV measurements were used to establish a point validation against which the high-resolution PIV measurements were validated. Subsequently, the high-resolution PIV measurements were used as a reference against which the low-resolution PIV data were assessed for error and uncertainty. We compared error and uncertainty distributions, spatially varying RMS error and RMS uncertainty, and standard uncertainty coverages. We observed that qualitatively, each method responded to spatially varying error (i.e. higher error regions resulted in higher uncertainty predictions in that region). However, the PPR and MI methods demonstrated reduced uncertainty dynamic range response. In contrast, the IM and CS methods showed better response, but under-predicted the uncertainty ranges. The standard coverages (68% confidence interval) ranged from

  13. A comparative experimental evaluation of uncertainty estimation methods for two-component PIV

    International Nuclear Information System (INIS)

    Boomsma, Aaron; Troolin, Dan; Pothos, Stamatios; Bhattacharya, Sayantan; Vlachos, Pavlos

    2016-01-01

    Uncertainty quantification in planar particle image velocimetry (PIV) measurement is critical for proper assessment of the quality and significance of reported results. New uncertainty estimation methods have been recently introduced generating interest about their applicability and utility. The present study compares and contrasts current methods, across two separate experiments and three software packages in order to provide a diversified assessment of the methods. We evaluated the performance of four uncertainty estimation methods, primary peak ratio (PPR), mutual information (MI), image matching (IM) and correlation statistics (CS). The PPR method was implemented and tested in two processing codes, using in-house open source PIV processing software (PRANA, Purdue University) and Insight4G (TSI, Inc.). The MI method was evaluated in PRANA, as was the IM method. The CS method was evaluated using DaVis (LaVision, GmbH). Utilizing two PIV systems for high and low-resolution measurements and a laser doppler velocimetry (LDV) system, data were acquired in a total of three cases: a jet flow and a cylinder in cross flow at two Reynolds numbers. LDV measurements were used to establish a point validation against which the high-resolution PIV measurements were validated. Subsequently, the high-resolution PIV measurements were used as a reference against which the low-resolution PIV data were assessed for error and uncertainty. We compared error and uncertainty distributions, spatially varying RMS error and RMS uncertainty, and standard uncertainty coverages. We observed that qualitatively, each method responded to spatially varying error (i.e. higher error regions resulted in higher uncertainty predictions in that region). However, the PPR and MI methods demonstrated reduced uncertainty dynamic range response. In contrast, the IM and CS methods showed better response, but under-predicted the uncertainty ranges. The standard coverages (68% confidence interval) ranged from

  14. A study on corrosion resistance of the Ti-10Mo experimental alloy after different processing methods

    International Nuclear Information System (INIS)

    Alves, A.P.R.; Santana, F.A.; Rosa, L.A.A.; Cursino, S.A.; Codaro, E.N.

    2004-01-01

    The purpose of this work was to evaluate the microstructure and corrosion resistance of the experimental Ti-10Mo (wt.%) alloy as-cast and treated. These alloys were divided into three groups for analysis: as-cast, after solution heat treatment at 1000 deg. C in argon atmosphere and remelting in centrifugal machine (investment casting). The microstructure formed from each condition was studied using optical microscopy. Corrosion behavior of titanium-molybdenum alloys in fluoridated physiological serum (0.15 M NaCl+0.03 M NaF [pH=6]) was studied and compared with Ti-6Al-4V alloy. In all electrodes systems, similar electrochemical response was obtained. In naturally aerated physiological serum, the corrosion rate is mainly controlled by dissolution process of a complex passive film. This film appears to be formed by titanium species with different oxidation states. Experimental Ti-10Mo alloy exhibit the lowest passive current densities, in particular, samples after heat treatment

  15. Quantitative fluorescence lifetime spectroscopy in turbid media: comparison of theoretical, experimental and computational methods

    International Nuclear Information System (INIS)

    Vishwanath, Karthik; Mycek, Mary-Ann; Pogue, Brian

    2002-01-01

    A Monte Carlo model developed to simulate time-resolved fluorescence propagation in a semi-infinite turbid medium was validated against previously reported theoretical and computational results. Model simulations were compared to experimental measurements of fluorescence spectra and lifetimes on tissue-simulating phantoms for single and dual fibre-optic probe geometries. Experiments and simulations using a single probe revealed that scattering-induced artefacts appeared in fluorescence emission spectra, while fluorescence lifetimes were unchanged. Although fluorescence lifetime measurements are generally more robust to scattering artefacts than are measurements of fluorescence spectra, in the dual-probe geometry scattering-induced changes in apparent lifetime were predicted both from diffusion theory and via Monte Carlo simulation, as well as measured experimentally. In all cases, the recovered apparent lifetime increased with increasing scattering and increasing source-detector separation. Diffusion theory consistently underestimated the magnitude of these increases in apparent lifetime (predicting a maximum increase of ∼15%), while Monte Carlo simulations and experiment were closely matched (showing increases as large as 30%). These results indicate that quantitative simulations of time-resolved fluorescence propagation in turbid media will be important for accurate recovery of fluorophore lifetimes in biological spectroscopy and imaging applications. (author)

  16. Methods and experimental coefficients used in the computation of reactor shielding; Methodes et coefficients experimentaux pour le calcul des protections de reacteurs

    Energy Technology Data Exchange (ETDEWEB)

    Bourgeois, J; Lafore, P; Millot, J P; Rastoin, J; Vathaire, F de [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    1) The concept of an effective removal cross section has been developed in order more easily to compute reactor shielding thicknesses. We have built an experimental facility for the purpose of measuring effective removal cross sections, the value of which had not been published at that time. The first part of this paper describes the device or facility used, the computation method applied, and the results obtained. 2) Starting from this concept, we endeavoured to define a removal cross section as a function of energy. This enabled us to use the method for computations bearing on the attenuation of fast neutrons of any spectrum. An experimental verification was carried out for the case of fission neutrons filtered by a substantial thickness of graphite. 3) Finally, we outline a computation method enabling us to determine the sources of captured gamma rays by the age theory and we give an example of the application in a composite shield. (author) [French] 1) La notion de section efficace effective de deplacement a ete introduite pour calculer commodement les epaisseurs de protection des reacteurs. Nous avons construit un dispositif experimental destine a mesurer les sections efficaces effectives de deplacement dont la valeur n'avait pas ete publiee a cette epoque. La premiere partie de cette communication decrit le dispositif utilise, la methode de calcul employee et les resultats obtenus. 2) A partir de cette notion, nous avons essaye de definir une section efficace de deplacement fonction de l'energie. Ceci permet d'utiliser la methode du deplacement pour des calculs d'attenuation de neutrons rapides dont le spectre est quelconque. Une verification experimentale a ete faite dans le cas de neutrons de fission filtres par une epaisseur notable de graphite. 3) Enfin une methode de calcul permettant de determiner les sources de gamma de capture par la theorie de l'age est exposee et un exemple d'application donne dans une protection composite. (auteur)

  17. Impact of dental implant insertion method on the peri-implant bone tissue: Experimental study

    Directory of Open Access Journals (Sweden)

    Stamatović Novak

    2013-01-01

    Full Text Available Background/Aim. The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. Methods. The experiment was performed on 9 dogs. Eight weeks following the extraction of lower premolars implants were inserted using the one-stage method on the right mandibular side and two-stage method on the left side. Three months after implantation the animals were sacrificed. Three distinct regions of bone tissue were histopathologically analyzed, the results were scored and compared. Results. In the specimens of one-stage implants increased amount of collagen fibers was found in 5 specimens where tissue necrosis was also observed. Only moderate osteoblastic activity was found in 3 sections. The analysis of bone-to-implant contact region revealed statistically significantly better results regarding the amount of collagen tissue fibers for the implants inserted in the two-stage method (Wa = 59 105, α = 0.05. No necrosis and osteoblastic activity were observed. Conclusion. Better results were achieved by the two-stage method in bone-to-implant contact region regarding the amount of collagen tissue, while the results were identical regarding the osteoblastic activity and bone tissue necrosis. There was no difference between the methods in the bone-implant interface region. In the bone tissue adjacent to the implant the results were identical regarding the amount of collagen tissue, osteoblastic reaction and bone tissue necrosis, while better results were achieved by the two-stage method regarding the number of osteocytes.

  18. How to measure time preferences: An experimental comparison of three methods

    Directory of Open Access Journals (Sweden)

    David J. Hardisty

    2013-05-01

    Full Text Available In two studies, time preferences for financial gains and losses at delays of up to 50 years were elicited using three different methods: matching, fixed-sequence choice titration, and a dynamic ``staircase'' choice method. Matching was found to create fewer demand characteristics and to produce better fits with the hyperbolic model of discounting. The choice-based measures better predicted real-world outcomes such as smoking and payment of credit card debt. No consistent advantages were found for the dynamic staircase method over fixed-sequence titration.

  19. Reproducible methods for experimental infection with Flavobacterium psychrophilum in rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Madsen, Lone; Dalsgaard, Inger

    1999-01-01

    , and this method was tested using isolates with different elastin- degrading profiles and representing different serotypes. Injecting trout, average weight 1 g, with 10(4) CFU (colony- forming units) per fish caused cumulative mortalities around 60 to 70%. The virulent strains belonged to certain serotypes...... and degraded elastin. The intraperitoneal injection challenge method could be used on larger fish, but the infection dose was 10(7) CFU per fish before mortalities occurred. Bath infection and bath infection in combination with formalin treatment (stress) seemed to be reproducible methods that could be used...

  20. Experimental study of icariin on vascular dementia in rats induced by 2-VO method

    Institute of Scientific and Technical Information of China (English)

    Rui-xiaXU; QinWU; Jing-shanSHI

    2004-01-01

    AIM: To study the effects of icariin (ICA) on the learning and memory of ischemic vascular dementia (VD) model of rats,and explore the protective mechanisms. METHODS: ICA was administered to the VD model rats induced by a permanent bilateral occlusion of both common carotids arteries(2-VO method) and by cerebral ischemia-reperfusion (I10-R 10-110 method). Morris water maze was used to examine the abilities of spatial learning and memory of VD model rats. The activity of SOD, level of

  1. Preliminary experimental study on the deterioration of cementitious materials by an acceleration method

    International Nuclear Information System (INIS)

    Saito, H.; Nakane, S.; Ikari, S.; Fujiwara, A.

    1992-01-01

    Development of a deterioration model for cementitious materials is important in assessing long-term integrity of nuclear waste repositories. The authors preliminarily examined a new test method for acceleration of aging of mortar specimens by application of electrical potential gradients and observed whether the method could throw light on the deterioration process of cementitious materials under repository conditions. As a result, it was concluded that the application of a potential gradient to a mortar specimen might be useful as an accelerated test method for assessing the deterioration behavior of cementitious materials due to leaching. (orig.)

  2. Non-linear thermal analysis of light concrete hollow brick walls by the finite element method and experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Del Coz Diaz, J.J.; Rodriguez, A. Martin; Martinez-Luengas, A. Lozano; Biempica, C. Betegon [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain); Nieto, P.J. Garcia [Departamento de Matematicas, Facultad de Ciencias, C/Calvo Sotelo s/n, 33007 Oviedo, Asturias (Spain)

    2006-06-15

    The finite element method (FEM) is applied to the non-linear complex heat transfer analysis of light concrete hollow brick walls. The non-linearity is due to the radiation boundary condition inside the inner holes of the bricks. The conduction and convection phenomena are taking into account in this study for three different values of the conductivity mortar and two values for the brick. Finally, the numerical and experimental results are compared and a good agreement is shown. [Author].

  3. Non-linear thermal analysis of light concrete hollow brick walls by the finite element method and experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Diaz del Coz, J.J. [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain)]. E-mail: juanjo@constru.uniovi.es; Nieto, P.J. Garcia [Departamento de Matematicas, Facultad de Ciencias, C/Calvo Sotelo s/n, 33007 Oviedo, Asturias (Spain); Rodriguez, A. Martin [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain); Martinez-Luengas, A. Lozano [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain); Biempica, C. Betegon [Department of Construction, University of Oviedo, Edificio Departamental Viesques No 7, Dpcho. 7.1.02 Campus de Viesques, 33204 Gijon, Asturias (Spain)

    2006-06-15

    The finite element method (FEM) is applied to the non-linear complex heat transfer analysis of light concrete hollow brick walls. The non-linearity is due to the radiation boundary condition inside the inner holes of the bricks. The conduction and convection phenomena are taking into account in this study for three different values of the conductivity mortar and two values for the brick. Finally, the numerical and experimental results are compared and a good agreement is shown.

  4. Non-linear thermal analysis of light concrete hollow brick walls by the finite element method and experimental validation

    International Nuclear Information System (INIS)

    Diaz del Coz, J.J.; Nieto, P.J. Garcia; Rodriguez, A. Martin; Martinez-Luengas, A. Lozano; Biempica, C. Betegon

    2006-01-01

    The finite element method (FEM) is applied to the non-linear complex heat transfer analysis of light concrete hollow brick walls. The non-linearity is due to the radiation boundary condition inside the inner holes of the bricks. The conduction and convection phenomena are taking into account in this study for three different values of the conductivity mortar and two values for the brick. Finally, the numerical and experimental results are compared and a good agreement is shown

  5. Analysis of progressive distorsion. Validation of the method based on effective primary stress. Discussion of Anderson's experimental data

    International Nuclear Information System (INIS)

    Moulin, Didier.

    1981-02-01

    An empirical rule usable for design by analysis against progressive distorsion has been set up from experiments conducted in C.E.N. Saclay. This rule is checked with experimental data obtained by W.F. ANDERSON, this experiment is sufficiently different from the Saclay one to evaluate the merits of the rule. The satisfactory results achieved, are another validation of the efficiency diagram on which the method is based [fr

  6. Measurement of proton capture reactions in the hot cycles: an evaluation of experimental methods

    Energy Technology Data Exchange (ETDEWEB)

    Leleux, P [Inst. de Physique Nucleaire, Univ. Catholique de Louvain, Louvain-la-Neuve (Belgium)

    1998-06-01

    In the hot cycles, most of the proton capture reactions involve radioactive nuclei in the entrance and exit channels. This paper evaluates the specific methods that were designed to measure such reactions. (orig.)

  7. Experimental study on the detection of free fluids and gases in waste packages by acoustic methods

    International Nuclear Information System (INIS)

    Eisenblaetter, J.; Schaefer, P.; Weib, R.

    1992-01-01

    The objective of the project was to evaluate the potential and the limits of various nondestructive methods for testing the contents of 200-litre drums filled with radioactive waste. The following test problems were to be studied: 1. Detection of free water on the surface of the waste matrix (concrete); 2. Determination of the waste matrix level; 3. Determination of internal gas pressure. The following methods were found to be suitable: For Test problem 1: Measurement of Lamb wave attenuation, Acoustic impedance measurement (AIM) and Analysis of swash sound; For Test problem 2: Acoustic impedance measurement (AIM) and Measurement of Lamb wave attenuation; For Test problem 3: A method of pressure compensation and Analysis of cover resonances after striking the cover. It was not possible, however, to detect the concrete level by localisation of friction points using acoustic emission methods. 53 figs

  8. Experimental electro-thermal method for nondestructively testing welds in stainless steel pipes

    International Nuclear Information System (INIS)

    Green, D.R.

    1979-01-01

    Welds in austenitic stainless steel pipes are notoriously difficult to nondestructively examine using conventional ultrasonic and eddy current methods. Survace irregularities and microscopic variations in magnetic permeability cause false eddy current signal variations. Ultrasonic methods have been developed which use computer processing of the data to overcome some of the problems. Electro-thermal nondestructive testing shows promise for detecting flaws that are difficult to detect using other NDT methods. Results of a project completed to develop and demonstrate the potential of an electro-thermal method for nondestructively testing stainless steel pipe welds are presented. Electro-thermal NDT uses a brief pulse of electrical current injected into the pipe. Defects at any depth within the weld cause small differences in surface electrical current distribution. These cause short-lived transient temperature differences on the pipe's surface that are mapped using an infrared scanning camera. Localized microstructural differences and normal surface roughness in the welds have little effect on the surface temperatures

  9. Experimental methods in cryogenic spectroscopy: Stark effect measurements in substituted myoglobin

    Science.gov (United States)

    Moran, Bradley M.

    Dawning from well-defined tertiary structure, the active regions of enzymatic proteins exist as specifically tailored electrostatic microenvironments capable of facilitating chemical interaction. The specific influence these charge distributions have on ligand binding dynamics, and their impact on specificity, reactivity, and biological functionality, have yet to be fully understood. A quantitative determination of these intrinsic fields would offer insight towards the mechanistic aspects of protein functionality. This work seeks to investigate the internal molecular electric fields that are present at the oxygen binding site of myoglobin. Experiments are performed at 1 K on samples located within a glassy matrix, using the high-resolution technique spectral hole-burning. The internal electric field distributions can be explored by implementing a unique mathematical treatment for analyzing the effect that externally applied electric fields have on the spectral hole profiles. Precise control of the light field, the temperature, and the externally applied electric field at the site of the sample is crucial. Experimentally, the functionality of custom cryogenic temperature confocal scanning microscope was extended to allow for collection of imaging and spectral data with the ability to modulate the polarization of the light at the sample. Operation of the instrumentation was integrated into a platform allowing for seamless execution of input commands with high temporal inter-instrument resolution for collection of data streams. For the regulated control and cycling of the sample temperature. the thermal characteristics of the research Dewar were theoretically modeled to systematically predict heat flows throughout the system. A high voltage feedthrough for delivering voltages of up to 5000 V to the sample as positioned within the Dewar was developed. The burning of spectral holes with this particular experimental setup is highly repeatable. The quantum mechanical

  10. Experimental study on method for heat transfer enhancement using a porous material

    International Nuclear Information System (INIS)

    Shimura, Takuya; Takeda, Tetsuaki

    2011-01-01

    There are several methods for enhancement of heat transfer; for example, there are attaching various fins on the heat transfer surface, processing the surface roughly, and so on. When cooling high temperature circular or rectangular channels by forced convection of gas, there are several methods for enhancement of heat transfer such as attaching radial or spiral fins on the channel surface or inserting twisted tape in the channel. In the case of the gas heating type steam reformer, disk type fins are attached on the outside surface of the reformer tube, and the tube is inserted into the guide tube to increase an amount of heat transferred from the high temperature gas. However, it has to take into consideration the deterioration of the structure strength by attaching the fins on the tube surface with the design of the steam reformer. The objective of this study is to clarify performances of a method for heat transfer enhancement using porous material with high porosity. The experiment has been performed using an apparatus which simulated the passage structure of the steam reformer to obtain characteristics of heat transfer and pressure drop. From the results obtained in this experiment, the heat transfer rate by this method showed a good performance in the laminar flow region. It was also found that the method for heat transfer enhancement using porous material with high porosity is further improved under the high temperature condition as compared with the other methods for heat transfer enhancement. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Tobajas, M.; Garcia-Calvo, E. [Dept. de Ingenieria Quimica, Univ. de Alcala, Alcala de Henares (Spain)

    2000-05-01

    Mass transfer in bioreactors has been examined. In the present work, dynamic methods are used for the determination of K{sub L}a 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 K{sub L}a 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 K{sub L}a does not interfere with the microorganisms action. A theoretical mass transfer model has been used for K{sub L}a 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. (orig.)

  12. Determination of the activation energy in a cast aluminium alloy by TEM and DSC

    International Nuclear Information System (INIS)

    Ovono Ovono, D.; Guillot, I.; Massinon, D.

    2007-01-01

    The precipitation behaviour and microstructure development of the A319 alloy during ageing were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM and STEM). During T5 treatment, θ' precipitates with an average size of about 18 nm were observed by TEM. The precipitate sizes increased with ageing temperature and attained an average size of 107 nm. In addition, there was a linear relationship between precipitate growth temperature and the cube of the precipitate size. This indicates that precipitate growth of the A319 alloy belongs to a thermal activated process of the Arrhenius type. The activation energy for the precipitate growth was calculated to be 140.4 ± 13.3 kJ/mol. However, under continuous heating conditions, the activation energy for the precipitate growth obtained by Kissinger plot was determined to be 119.5 ± 8.3 kJ/mol. Allowing for experimental error, both values are comparable and are related to the diffusion of Cu and/or Si in Al

  13. Comparison of first pass bolus AIFs extracted from sequential {sup 18}F-FDG PET and DSC-MRI of mice

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Eleanor, E-mail: ee244@cam.ac.uk [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Sawiak, Stephen J. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Behavioural and Clinical Neuroscience Institute, Department of Experimental Psychology, University of Cambridge, Cambridge, CB2 3EB (United Kingdom); Ward, Alexander O.; Buonincontri, Guido; Hawkes, Robert C.; Adrian Carpenter, T. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom)

    2014-01-11

    Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and {sup 18}F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies.

  14. Heat capacity of Sr10(PO4)6Cl2 and Ca10(PO4)6Cl2 by DSC

    International Nuclear Information System (INIS)

    Venkata Krishnan, R.; Jena, Hrudananda; Govindan Kutty, K.V.; Nagarajan, K.

    2008-01-01

    Strontium and calcium chloroapatites were synthesized by wet chemical method, characterized by X-ray diffraction and are found to be phase pure materials. The measured room temperature lattice parameter of Ca 10 (PO 4 ) 6 Cl 2 is a = 9.523 A, c = 6.855 A and for Sr 10 (PO 4 ) 6 Cl 2 is a = 9.876 A, c = 7.188 A. Heat capacity measurements were carried out on Ca 10 (PO 4 ) 6 Cl 2 and Sr 10 (PO 4 ) 6 Cl 2 by DSC in the temperature range 298-800 K. The heat capacity values of Sr 10 (PO 4 ) 6 Cl 2 is higher at all temperatures than Ca 10 (PO 4 ) 6 Cl 2 . Enthalpy and entropy increments were computed. Heat capacity values of Ca 10 (PO 4 ) 6 Cl 2 and Sr 10 (PO 4 ) 6 Cl 2 at 298 K are 758 and 868 J K -1 mol -1 , respectively

  15. ac impedance, DSC and FT-IR investigations on (x)PVAc-(1 - x)PVdF blends with LiClO4

    International Nuclear Information System (INIS)

    Baskaran, R.; Selvasekarapandian, S.; Kuwata, N.; Kawamura, J.; Hattori, T.

    2006-01-01

    The blended polymer electrolytes comprising poly(vinyl acetate) (PVAc)-poly(vinylidene fluoride) (PVdF) have been prepared for different blend composition with constant lithium perchlorate (LiClO 4 ) ratio by solution casting technique. The formation of the blend polymer electrolyte complex has been confirmed by FT-IR spectroscopy analysis. DSC analysis has been performed in order to observe the change in transition temperature that is caused by the blending of polymers and addition of LiClO 4 . The ac impedance and dielectric spectroscopy studies are carried out on the blended matrix to identify the optimized blend composition, which is having high ionic conductivity. The temperature dependence of conductivity of the polymer electrolytes is found to follow VTF type equation. The high ionic conductivity of 6.4 x 10 -4 S cm -1 at 343 K has been observed for blended polymer electrolyte having blend ratio 75:25 (PVAc:PVdF). The ionic transference number of mobile ions has been estimated by Wagner's polarization method and the value is reported to be t ion is 0.95-0.98 for all the blended samples. The modulus spectra reveal the non-Debye nature and distribution of relaxation times of the samples. The dielectric spectra show the low frequency dispersion, which implies the space charge effects arising from the electrodes

  16. A dynamic method to forecast the wheel slip for antilock braking system and its experimental evaluation.

    Science.gov (United States)

    Oniz, Yesim; Kayacan, Erdal; Kaynak, Okyay

    2009-04-01

    The control of an antilock braking system (ABS) is a difficult problem due to its strongly nonlinear and uncertain characteristics. To overcome this difficulty, the integration of gray-system theory and sliding-mode control is proposed in this paper. This way, the prediction capabilities of the former and the robustness of the latter are combined to regulate optimal wheel slip depending on the vehicle forward velocity. The design approach described is novel, considering that a point, rather than a line, is used as the sliding control surface. The control algorithm is derived and subsequently tested on a quarter vehicle model. Encouraged by the simulation results indicating the ability to overcome the stated difficulties with fast convergence, experimental results are carried out on a laboratory setup. The results presented indicate the potential of the approach in handling difficult real-time control problems.

  17. Development of the experimental evaluation method for crevice chemistry in steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Rhee, In Hyoung [Soonchunghyang Univ., Cheonan (Korea); Hwang, Il Soon; Lee, Na Young; Kim, Ji Hyun; Lim, Jung Yeon; Bahn, Chi Bum; Oh, Young Jin; Han, Byung Chan; Oh, Si Hyoung [Seoul National Univ., Seoul (Korea)

    2001-04-01

    Steam generator tube degradation problems is very sensitive to water chemistry. But even if the secondary water chemistry is well controlled, it is needed. Tubesheet crevice has three boiling regimes with depth: liquid penetration and discharge(or wet) region, liquid drop scattering(or dry and wet) region, and dryout region. This results showed a good agreement with earlier works. High temperature, high pressure tubesheet crevice simulation system was constructed. As {delta}T increased, the temperature gradient in crevice and time constant for concentration increased. When the experimental results were compared with MULTEQ calculation results, a similar behavior was shown, packed crevice have longer time constant for Na concentration and showed heavier concentration that open crevice. The verification experiment for Molar Ratio Control and advanced Molar Ration Control test were conducted. To check the applicability of boric acid as pH neutralizer another experiment was conducted. 40 refs., 102 figs., 3 tabs. (Author)

  18. A method of simulating voids in experimental studies of boiling water reactors

    International Nuclear Information System (INIS)

    Down, H.J.; Dickie, J.; Fox, W.N.

    1963-11-01

    The coolant density in boiling water reactors may vary from 3 at pressures up to 1000 p.s.i. In order to study the effect of reduced water density on reactivity in unpressurized experimental systems, the effective water density is reduced by packing small beads of highly expanded polystyrene into the fuel clusters and flooding the interstices with water. Coolant densities of from 0.4 to 0.6 gm/cm 3 may be produced with the introduction of only about 0.4 gm/cm 3 of non-hydrogeneous material. This memorandum describes the production, properties and handling of polystyrene beads and the tests carried out to establish the validity of the technique. (author)

  19. New Issues for New Methods: Ethical and Editorial Challenges for an Experimental Philosophy.

    Science.gov (United States)

    Polonioli, Andrea

    2017-08-01

    This paper examines a constellation of ethical and editorial issues that have arisen since philosophers started to conduct, submit and publish empirical research. These issues encompass concerns over responsible authorship, fair treatment of human subjects, ethicality of experimental procedures, availability of data, unselective reporting and publishability of research findings. This study aims to assess whether the philosophical community has as yet successfully addressed such issues. To do so, the instructions for authors, submission process and published research papers of 29 main journals in philosophy have been considered and analyzed. In light of the evidence reported here, it is argued that the philosophical community has as yet failed to properly tackle such issues. The paper also delivers some recommendations for authors, reviewers and editors in the field.

  20. Optimization of single-walled carbon nanotube solubility by noncovalent PEGylation using experimental design methods

    Directory of Open Access Journals (Sweden)

    Hadidi N

    2011-04-01

    Full Text Available Naghmeh Hadidi1, Farzad Kobarfard2, Nastaran Nafissi-Varcheh3, Reza Aboofazeli11Department of Pharmaceutics, 2Department of Pharmaceutical Chemistry, 3Department of Pharmaceutical Biotechnology, School of Pharmacy, Shaheed Beheshti University of Medical Sciences, Tehran, IranAbstract: In this study, noncovalent functionalization of single-walled carbon nanotubes (SWCNTs with phospholipid-polyethylene glycols (Pl-PEGs was performed to improve the solubility of SWCNTs in aqueous solution. Two kinds of PEG derivatives, ie, Pl-PEG 2000 and Pl-PEG 5000, were used for the PEGylation process. An experimental design technique (D-optimal design and second-order polynomial equations was applied to investigate the effect of variables on PEGylation and the solubility of SWCNTs. The type of PEG derivative was selected as a qualitative parameter, and the PEG/SWCNT weight ratio and sonication time were applied as quantitative variables for the experimental design. Optimization was performed for two responses, aqueous solubility and loading efficiency. The grafting of PEG to the carbon nanostructure was determined by thermogravimetric analysis, Raman spectroscopy, and scanning electron microscopy. Aqueous solubility and loading efficiency were determined by ultraviolet-visible spectrophotometry and measurement of free amine groups, respectively. Results showed that Pl-PEGs were grafted onto SWCNTs. Aqueous solubility of 0.84 mg/mL and loading efficiency of nearly 98% were achieved for the prepared Pl-PEG 5000-SWCNT conjugates. Evaluation of functionalized SWCNTs showed that our noncovalent functionalization protocol could considerably increase aqueous solubility, which is an essential criterion in the design of a carbon nanotube-based drug delivery system and its biodistribution.Keywords: phospholipid-PEG, D-optimal design, loading efficiency, Raman spectroscopy, scanning electron microscopy, theromogravimetric analysis, carbon nanotubes