Substrate dependent physical properties of evaporated CdO thin films for optoelectronic applications

Energy Technology Data Exchange (ETDEWEB)

Purohit, Anuradha; Chander, S.; Patel, S.L. [Department of Physics, Mohanlal Sukhadia University, Udaipur-313001 (India); Rangra, K.J. [Sensors and Transducers Group, CSIR-CEERI, Pilani-333031 (India); Dhaka, M.S., E-mail: msdhaka75@yahoo.co.in [Department of Physics, Mohanlal Sukhadia University, Udaipur-313001 (India)

2017-06-15

Highlights: • Substrate dependent physical properties of CdO thin films are carried out. • XRD patterns reveal that the films have cubic structure of space group Fm3m. • Optical direct band gap is found to vary with the substrates. • SEM images show that the films are compact and homogeneous. • I–V characteristics show ohmic behavior of the deposited CdO films. - Abstract: In this study, CdO thin films were grown by e-beam evaporation technique on glass, indium tin oxide (ITO), fluorine-doped tin oxide (FTO) and silicon (Si) wafer. The deposited films were analyzed by X-ray diffraction (XRD), UV–Vis spectrophotometer, scanning electron microscopy, energy dispersive spectroscopy (EDS) and source meter (current–voltage) for structural, optical, surface morphological, elemental and electrical analysis, respectively. The films have single phase of cubic structure (space group Fm3m) with (200) preferred orientation. The structural parameters viz. inter-planar spacing, grain size, lattice constant, internal strain and dislocation density are calculated and found to vary with the nature of the substrates. The optical band gap was found in the range 2.24–3.95 eV and strongly dependents on the substrates. The SEM analysis shows that the films are compact, homogeneous and have granular structure without any defects like pin holes and cracks. The EDS spectra confirmed the presence of cadmium (Cd) and oxygen (O) in the films deposited on different substrates. The current–voltage characteristics of the films show ohmic behavior.

Hierarchical and Size Dependent Mechanical Properties of Silica and Silicon Nanostructures Inspired by Diatom Algae

Science.gov (United States)

2010-09-01

Chaniotakis. The physical and mechanical properties of composite cements manufactured with cal- careous and clayey greek diatomite mixtures. Cement and...Hierarchical and size dependent mechanical properties of silica and silicon nanostructures inspired by diatom algae by Andre Phillipe Garcia B.S...dependent mechanical properties of silica and silicon nanostructures inspired by diatom algae 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

Physical properties of solids

International Nuclear Information System (INIS)

Anon.

1977-01-01

Research at ORNL into the physical properties of solids is described. Topics covered include: optical, electrical, and magnetic properties of magnesium oxide; ionic conductivity and superconductivity; surface physics and catalysis; defects and impurities in insulating crystals; photovoltaic conversion of solar energy; and fracture studies

Physical properties of solids

Energy Technology Data Exchange (ETDEWEB)

Wilkinson, M. K.; Young, Jr, F. W.

1977-10-01

Research at ORNL into the physical properties of solids is described. Topics covered include: optical, electrical, and magnetic properties of magnesium oxide; ionic conductivity and superconductivity; surface physics and catalysis; defects and impurities in insulating crystals; photovoltaic conversion of solar energy; and fracture studies. (GHT)

Aluminium effect on the physical properties of titanium

International Nuclear Information System (INIS)

Nazimov, O.P.; Il'in, A.A.; Zvonova, L.N.

1977-01-01

The effect of aluminium on the physical properties of titanium was investigated. Within the framework of the configuration model of matter it is shown that a change in physical properties with an aluminium content of up to 7.5 wt.% in alloys depends on the phase composition and electron structure. In interacting with titanium, aluminium exhibits acceptor properties, causing d→s electron transitions. The electrons which have shifted to the s-state are partly collectivized and partly localized into quasistable sp 3 configurations, with the resulting increase of the interatomic forces. An intensification of d→s transitions in alloying of titanium with aluminium stabilizes the α-phase. Predominance of d 1 configurations in the intermediate spectrum in the region of the α-solution increases the ratio of the axes of the HCP lattice and determines the electron type of conduction of alloys of the Ti-Al system

Natural Gas : Physical Properties and Combustion Features

OpenAIRE

Corre, Olivier Le; Loubar, Khaled

2010-01-01

The actual composition of natural gas depends primarily on the production field from which it is extracted and limited variations in composition must therefore be accepted. Moreover, at a local distribution level, seasonal adjustments by the local gas distributor may cause significant variations in the gas composition. Consequently, physical properties and energy content are subject to variations and their calculation / estimation is of great importance for technical and economical aspects. I...

Psychometric properties of the PROMIS Physical Function item bank in patients receiving physical therapy.

Directory of Open Access Journals (Sweden)

Martine H P Crins

Full Text Available The Patient-Reported Outcomes Measurement Information System (PROMIS is a universally applicable set of instruments, including item banks, short forms and computer adaptive tests (CATs, measuring patient-reported health across different patient populations. PROMIS CATs are highly efficient and the use in practice is considered feasible with little administration time, offering standardized and routine patient monitoring. Before an item bank can be used as CAT, the psychometric properties of the item bank have to be examined. Therefore, the objective was to assess the psychometric properties of the Dutch-Flemish PROMIS Physical Function item bank (DF-PROMIS-PF in Dutch patients receiving physical therapy.Cross-sectional study.805 patients >18 years, who received any kind of physical therapy in primary care in the past year, completed the full DF-PROMIS-PF (121 items.Unidimensionality was examined by Confirmatory Factor Analysis and local dependence and monotonicity were evaluated. A Graded Response Model was fitted. Construct validity was examined with correlations between DF-PROMIS-PF T-scores and scores on two legacy instruments (SF-36 Health Survey Physical Functioning scale [SF36-PF10] and the Health Assessment Questionnaire Disability-Index [HAQ-DI]. Reliability (standard errors of theta was assessed.The results for unidimensionality were mixed (scaled CFI = 0.924, TLI = 0.923, RMSEA = 0.045, 1th factor explained 61.5% of variance. Some local dependence was found (8.2% of item pairs. The item bank showed a broad coverage of the physical function construct (threshold-parameters range: -4.28-2.33 and good construct validity (correlation with SF36-PF10 = 0.84 and HAQ-DI = -0.85. Furthermore, the DF-PROMIS-PF showed greater reliability over a broader score-range than the SF36-PF10 and HAQ-DI.The psychometric properties of the DF-PROMIS-PF item bank are sufficient. The DF-PROMIS-PF can now be used as short forms or CAT to measure the level of

MAGNETIC WOVEN FABRICS - PHYSICAL AND MAGNETIC PROPERTIES

Directory of Open Access Journals (Sweden)

GROSU Marian C

2015-05-01

Full Text Available A coated material is a composite structure that consists of at least two components: base material and coating layer. The purpose of coating is to provide special properties to base material, with potential to be applied in EMI shielding and diverse smart technical fields. This paper reports the results of a study about some physical and magnetic properties of coated woven fabrics made from cotton yarns with fineness of 17 metric count. For this aim, a plain woven fabric was coated with a solution hard magnetic polymer based. As hard magnetic powder, barium hexaferrite (BaFe12O19 was selected. The plain woven fabric used as base has been coated with five solutions having different amounts of hard magnetic powder (15% - 45% in order to obtain five different magnetic woven fabrics. A comparison of physical properties regarding weight (g/m2, thickness (mm, degree of charging (% and magnetic properties of magnetic woven samples were presented. Saturation magnetizing (emu/g, residual magnetizing (emu/g and coercive force (kA/m of pure hard magnetic powder and woven fabrics have been studied as hysteresis characteristics. The magnetic properties of the woven fabrics depend on the mass percentage of magnetic powder from coating solution. Also, the residual magnetism and coercive field of woven fabrics represents only a part of bulk barium hexafferite residual magnetism and coercive field.

Physical properties and fisheries

Digital Repository Service at National Institute of Oceanography (India)

Antony, M.K.

The physical aspects influencing the different stages of behaviour of the marine fish can be divided into two categories (1) the physical properties of the ocean like temperature, salinity, oxygen, high penetration etc.; and (2) the physical...

Determination of composition and physical properties of partially ionized plasmas in the function of temperature

International Nuclear Information System (INIS)

Zaporowski, B.

1992-01-01

The investigations of various kinds of partially ionized plasma were conducted for the pressure of 0.1 MPa and in the range of temperature of 298.15 K to 24000 K. The physical properties of various kinds of partially ionized plasma depend mainly of their composition and temperature. The composition of particular kinds of partially ionized plasmas varies also in the function of temperature. Simultaneous going on of physical and chemical processes in plasma is the reason of difficulties in the calculations of plasma's physical properties. The use of the laws of macroscopic thermodynamics for the calculations of physical properties of partially ionized plasma is impossible. There are enough exact methods for measuring of physical properties of partially ionized plasma. For these reasons the theoretical method using the base of statistic physics was used to calculate the composition and physical properties of various kinds of partially ionized plasma. (author) 2 refs., 2 figs

Estimation of Physical Properties for Hydrogen Isotopes Using Aspen Plus Simulator

International Nuclear Information System (INIS)

Cho, Jung Ho; Yun, Sei Hun; Cho, Seung Yon; Chang, Min Ho; Kang, Hyun Goo; Jung, Ki Jung; Kim, Dong Min

2009-01-01

Hydrogen isotopes are H 2 , HD, D 2 , H 2 , HD, D 2 , HT, DT and T 2 . Among the hydrogen isotopes, the physical properties of H2, HD and D+2 are included in the Aspen Plus, however HT, D T and T 2 are not included. In this study, various thermodynamic properties were estimated for six components of isotopes by use of the fixed properties and temperature-dependent properties. To estimate thermodynamic properties, Soave modified Redlich-Kwong equation of state and Aspenplus simulator was used. The results were verified and compared with by PRO/II with PROVISION of Invensys

Mineralogy of the clay fraction of alfisols in two slope curvatures: IV - spatial correlation with physical properties

Directory of Open Access Journals (Sweden)

Livia Arantes Camargo

2013-04-01

Full Text Available Although the influence of clay mineralogy on soil physical properties has been widely studied, spatial relationships between these features in Alfisols have rarely been examined. The purpose of this work was to relate the clay minerals and physical properties of an Alfisol of sandstone origin in two slope curvatures. The crystallographic properties such as mean crystallite size (MCS and width at half height (WHH of hematite, goethite, kaolinite and gibbsite; contents of hematite and goethite; aluminium substitution (AS and specific surface area (SSA of hematite and goethite; the goethite/(goethite+hematite and kaolinite/(kaolinite+gibbsite ratios; and the citrate/bicarbonate/dithionite extractable Fe (Fe d were correlated with the soil physical properties through Pearson correlation coefficients and cross-semivariograms. The correlations found between aluminium substitution in goethite and the soil physical properties suggest that the degree of crystallinity of this mineral influences soil properties used as soil quality indicators. Thus, goethite with a high aluminium substitution resulted in large aggregate sizes and a high porosity, and also in a low bulk density and soil penetration resistance. The presence of highly crystalline gibbsite resulted in a high density and micropore content, as well as in smaller aggregates. Interpretation of the cross-semivariogram and classification of landscape compartments in terms of the spatial dependence pattern for the relief-dependent physical and mineralogical properties of the soil proved an effective supplementary method for assessing Pearson correlations between the soil physical and mineralogical properties.

Review on Synthesis, Thermo-Physical Property, and Heat Transfer Mechanism of Nanofluids

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Mahesh Suresh Patil

2016-10-01

Full Text Available Nanofluids are suspended nano-sized particles in a base fluid. With increasing demand for more high efficiency thermal systems, nanofluids seem to be a promising option for researchers. As a result, numerous investigations have been undertaken to understand the behaviors of nanofluids. Since their discovery, the thermo-physical properties of nanofluids have been under intense research. Inadequate understanding of the mechanisms involved in the heat transfer of nanofluids has been the major obstacle for the development of sophisticated nanofluids with the desired properties. In this comprehensive review paper, investigations on synthesis, thermo-physical properties, and heat transfer mechanisms of nanofluids have been reviewed and presented. Results show that the thermal conductivity of nanofluids increases with the increase of the operating temperature. This can potentially be used for the efficiency enhancement of thermal systems under higher operating temperatures. In addition, this paper also provides details concerning dependency of the thermo-physical properties as well as synthesis and the heat transfer mechanism of the nanofluids.

The physical properties and compaction characteristics of swelling soils

International Nuclear Information System (INIS)

Komine, Hideo; Ogata, Nobuhide

1990-01-01

Expansive soils have recently attracted increasing attention as the back filling material for the repositories of high level nuclear wastes or as the material for improving extremely soft grounds. However, since very little has been known concerning the physical and mechanical properties of such materials, it is necessary to clarify the swelling, compaction and thermal characteristics of expansive soils. For this purpose, various kinds of index tests and a series of static compaction tests were performed using several kinds of swelling soils in order to investigate the relationship between the fundamental physical properties and the compaction characteristics. Since the ordinary testing method stipulated in JIS is difficult to perform for such expansive soils, the new method was proposed to obtained the reliable values of specific gravity, grain size distribution and liquid/plastic limits. By this method, some representative values were presented for various kinds of clay including bentonite. As the results of static compaction tests, the compaction characteristics of clay were strongly dependent on the plastic limit of clay. The maximum dry density and optimum water content were strongly dependent on both plastic limit and compaction pressure. (K.I.)

Basic Physical - Mechanical Properties of Geopolymers Depending on the Content of Ground Fly Ash and Fines of Sludge

Science.gov (United States)

Sičáková, Alena; Števulová, Nadežda

2017-06-01

The binding potential of fly ash (FA) as a typical basic component of building mixtures can be improved in mechanical way, which unfolds new possibilities of its utilization. This paper presents the possibilities of preparing the geopolymer mixtures based on ground (dm = 31.0 μm) FA, used in varying percentages to the original (unground; dm = 74.1 μm) one. As a modification, fine-grain sludge from the process of washing the crushed aggregates was used as filler in order to obtain mortar-type material. The basic physical-mechanical properties of mixtures are presented and discussed in the paper, focusing on time dependence. The following standard tests were executed after 2, 7, 28, and 120 days: density, total water absorption, flexural strength, and compressive strength. Ground FA provided for positive effect in all tested parameters, while incorporation of fine portion of sludge into the geopolymer mixture does not offer a significant technical profit. On the other hand, it does not cause the decline in the properties, so the environmental effect (reduction of environmental burden) can be applied through its incorporation into the geopolymer mixtures.

Temperature dependence of the physical properties of Bose–Einstein condensed gases and liquids

International Nuclear Information System (INIS)

Mayers, J

2014-01-01

It is shown that in the presence of Bose–Einstein condensation (BEC) in any N particle system, the N particle Schrödinger wave functions of thermally occupied states are the sum of a ‘localized’ component and a ‘delocalized’ component, identical to the ground state wave function. It is shown that if N is sufficiently large, this implies that all physical properties of the system are the sum of two independent contributions from these two components. These results are used here to provide quantitative explanations of fundamental properties of BE condensed liquid 4 He, unexplained even qualitatively by existing theory; why BE condensed liquid 4 He is the only known physical system in which pair correlations between atomic positions reduce as it is cooled, why it is the only known liquid with sharp peaks in its dynamic structure factor, why the liquid expands with cooling and how the condensate fraction is related to the superfluid fraction. It is shown that these results also provide a relatively simple, physically transparent and quantitative explanation from first principles of macroscopic quantum effects. A new algorithm is given for the calculation of the time development of the macroscopic density of any BE condensed liquid or gas at any temperature. Unlike the Gross–Pitaevskii equation, this algorithm is valid for both strongly and weakly interacting systems. It is used here to show that macroscopic quantum interference fringes, observed between overlapping clouds of BE condensed atoms, are a necessary consequence of BEC and the N particle Schrödinger equation for the atoms in the clouds. It follows that the widely held view that these fringes are created by measurement is unnecessary. New, experimentally testable predictions are made of how the visibility of these fringes will vary with temperature. (paper)

Correlation between some mechanical and physical properties of polycrystalline graphites

International Nuclear Information System (INIS)

Yoda, Shinichi; Fujisaki, Katsuo

1982-01-01

Mechanical and physical properties of polycrystalline graphites, tensile strength, compressive strength, flexural strength, Young's modulus, thermal expansion coefficient, electrical resistivity, volume fraction of porosity, and graphitisation were measured for ten brand graphites. Correlation between the mechanical and physical properties of the graphites were studied. Young's modulus and thermal expansion coefficient of the graphites depend on volume fraction of porosity. The Young's modulus of the graphites tended to increase with increasing the thermal expansion coefficient. For an anisotropic graphite, an interesting relationship between the Young's modulus E and the thermal expansion coefficient al pha was found in any specimen orientations; alpha E=constant. The value of alphah E was dependent upon the volume fraction of porosity. It should be noted here that the electrical resistivity increased with decreasing grain size. The flexural and the compressive strength were related with the volume fraction of porosity while the tensile strength was not, The relationships between the tensile, the compressive and the flexural strength can be approximately expressed as linear functions over a wide range of the stresses. (author)

Temperature and pressure dependent structural and thermo-physical properties of quaternary CoVTiAl alloy

Science.gov (United States)

Yousuf, Saleem; Gupta, Dinesh C.

2017-09-01

Investigation of band structure and thermo-physical response of new quaternary CoVTiAl Heusler alloy within the frame work of density functional theory has been analyzed. 100% spin polarization with ferromagnetic stable ground state at the optimized lattice parameter of 6.01 Å is predicted for the compound. Slater-Pauling rule for the total magnetic moment of 3 μB and an indirect semiconducting behavior is also seen for the compound. In order to perfectly analyze the thermo-physical response, the lattice thermal conductivity and thermodynamic properties have been calculated. Thermal effects on some macroscopic properties of CoVTiAl are predicted using the quasi-harmonic Debye model, in which the lattice vibrations are taken into account. The variations of the lattice constant, volume expansion coefficient, heat capacities, and Debye temperature with pressure and temperature in the ranges of 0 GPa to 15 GPa and 0 K to 800 K have been obtained.

Centrality dependence of bulk fireball properties in √(sNN)=200 GeV Au-Au collisions

International Nuclear Information System (INIS)

Rafelski, Johann; Letessier, Jean; Torrieri, Giorgio

2005-01-01

We explore the centrality dependence of the properties of the dense hadronic matter created in √(s NN )=200 GeV Au-Au collisions at the Relativistic Heavy Ion Collider. Using the statistical hadronization model, we fit particle yields known for 11 centrality bins. We present the resulting model parameters, rapidity yields of physical quantities, and the physical properties of bulk matter at hadronization as function of centrality. We discuss the production of strangeness and entropy

Analysis of the effect of pore geometry in the physical properties of rocks

Directory of Open Access Journals (Sweden)

Luiz Alberto Oliveira Lima Roque

2012-12-01

Full Text Available Pore geometry is one of the main factors influencing the flow of reservoir fluids under pressure. Pores with narrower formats are more easily compressed when subject to pressure. Pressure modifies pore geometry by opening or closing cracks, causing increase or decrease in the elastic modulus, porosity, permeability, and other parameters. Rock physical properties depend on the size and shape of pores. Thus, in order to analyze changes on the physical properties behavior according to the pores geometry, it is necessary to study and improve mathematical models of the porous media by taking into account the pore shape factor for estimating rock elastic properties. Differential effective medium model (DEM, Hertz-Mindlin theory and coherent potential approximation (CPA are some of the theoretical paradigms that take into account pore geometry in changes in elastic moduli. Given the importance of the pore structure effect on the behavior of physical parameters, this article proposes an analysis of some mathematical models that consider the influence of pore shapes in the physical properties of rocks.

Unified scaling behavior of physical properties of clays in alcohol solutions.

Science.gov (United States)

Pujala, Ravi Kumar; Pawar, Nisha; Bohidar, H B

2011-12-15

This paper reports observation of universal scaling of physical properties of clay particles, Laponite (aspect ratio=30) (L) and Na Montmorillonite (MMT, aspect ratio=200), in aqueous alcohol solutions (methanol, ethanol and 1-propanol) with solvent polarity, defined through reaction field factor f(OH)(ɛ(0),n)=[(ɛ(0) - 1/ɛ(0) + 2) - (n(2) - 1/n(2) + 2)], at room temperature (20°C). Here, ɛ(0) and n are the static dielectric constant and refractive index of the solvent concerned. Physical properties (Z) such as zeta potential, effective aggregate size, viscosity and surface tension scaled with the relative solvent polarity as Z∼δf(α); δf=(f(w)(ɛ(0),n) - f(OH)(ɛ(0),n)), where f(w)(ɛ(0),n) is the reaction field factor for water, Z is the normalized physical property, and α is its characteristic scaling exponent. The value of this exponent was found to be invariant of aspect ratio of the clay but dependent on the solvent polarity only. Copyright © 2011 Elsevier Inc. All rights reserved.

A study on physical properties of concrete and reinforcement at elevated temperatures

International Nuclear Information System (INIS)

Kanazu, Tsutomu

2002-01-01

Reinforced concrete structures such as a containment vessel, a support of the reactor, piping systems and facilities for storing high level radioactive waste in a nuclear power plant are exposed to a high temperature condition. Changes of physical properties of concrete and reinforcement caused by high temperature influence on mechanical behavior of these structures and internal stresses are induced by difference of thermal coefficients between concrete and reinforcement that was reported in the previous paper by the author. These are the special features in high temperature conditions. Temperature dependence of physical properties of concrete and reinforcement are summarized in the paper based on the experimental results. (author)

Sampling Design of Soil Physical Properties in a Conilon Coffee Field

Directory of Open Access Journals (Sweden)

Eduardo Oliveira de Jesus Santos

Full Text Available ABSTRACT Establishing the number of samples required to determine values of soil physical properties ultimately results in optimization of labor and allows better representation of such attributes. The objective of this study was to analyze the spatial variability of soil physical properties in a Conilon coffee field and propose a soil sampling method better attuned to conditions of the management system. The experiment was performed in a Conilon coffee field in Espírito Santo state, Brazil, under a 3.0 × 2.0 × 1.0 m (4,000 plants ha-1 double spacing design. An irregular grid, with dimensions of 107 × 95.7 m and 65 sampling points, was set up. Soil samples were collected from the 0.00-0.20 m depth from each sampling point. Data were analyzed under descriptive statistical and geostatistical methods. Using statistical parameters, the adequate number of samples for analyzing the attributes under study was established, which ranged from 1 to 11 sampling points. With the exception of particle density, all soil physical properties showed a spatial dependence structure best fitted to the spherical model. Establishment of the number of samples and spatial variability for the physical properties of soils may be useful in developing sampling strategies that minimize costs for farmers within a tolerable and predictable level of error.

Basic Physical – Mechanical Properties of Geopolymers Depending on the Content of Ground Fly Ash and Fines of Sludge

Directory of Open Access Journals (Sweden)

Sičáková Alena

2017-06-01

Full Text Available The binding potential of fly ash (FA as a typical basic component of building mixtures can be improved in mechanical way, which unfolds new possibilities of its utilization. This paper presents the possibilities of preparing the geopolymer mixtures based on ground (dm = 31.0 μm FA, used in varying percentages to the original (unground; dm = 74.1 μm one. As a modification, fine-grain sludge from the process of washing the crushed aggregates was used as filler in order to obtain mortar-type material. The basic physical-mechanical properties of mixtures are presented and discussed in the paper, focusing on time dependence. The following standard tests were executed after 2, 7, 28, and 120 days: density, total water absorption, flexural strength, and compressive strength. Ground FA provided for positive effect in all tested parameters, while incorporation of fine portion of sludge into the geopolymer mixture does not offer a significant technical profit. On the other hand, it does not cause the decline in the properties, so the environmental effect (reduction of environmental burden can be applied through its incorporation into the geopolymer mixtures.

Anisotropic bias dependent transport property of defective phosphorene layer

Science.gov (United States)

Umar Farooq, M.; Hashmi, Arqum; Hong, Jisang

2015-01-01

Phosphorene is receiving great research interests because of its peculiar physical properties. Nonetheless, no systematic studies on the transport properties modified due to defects have been performed. Here, we present the electronic band structure, defect formation energy and bias dependent transport property of various defective systems. We found that the defect formation energy is much less than that in graphene. The defect configuration strongly affects the electronic structure. The band gap vanishes in single vacancy layers, but the band gap reappears in divacancy layers. Interestingly, a single vacancy defect behaves like a p-type impurity for transport property. Unlike the common belief, we observe that the vacancy defect can contribute to greatly increasing the current. Along the zigzag direction, the current in the most stable single vacancy structure was significantly increased as compared with that found in the pristine layer. In addition, the current along the armchair direction was always greater than along the zigzag direction and we observed a strong anisotropic current ratio of armchair to zigzag direction. PMID:26198318

Scale dependence of effective media properties

International Nuclear Information System (INIS)

Tidwell, V.C.; VonDoemming, J.D.; Martinez, K.

1992-01-01

For problems where media properties are measured at one scale and applied at another, scaling laws or models must be used in order to define effective properties at the scale of interest. The accuracy of such models will play a critical role in predicting flow and transport through the Yucca Mountain Test Site given the sensitivity of these calculations to the input property fields. Therefore, a research programhas been established to gain a fundamental understanding of how properties scale with the aim of developing and testing models that describe scaling behavior in a quantitative-manner. Scaling of constitutive rock properties is investigated through physical experimentation involving the collection of suites of gas permeability data measured over a range of discrete scales. Also, various physical characteristics of property heterogeneity and the means by which the heterogeneity is measured and described are systematically investigated to evaluate their influence on scaling behavior. This paper summarizes the approach that isbeing taken toward this goal and presents the results of a scoping study that was conducted to evaluate the feasibility of the proposed research

Physical Properties of Gas Hydrates: A Review

Energy Technology Data Exchange (ETDEWEB)

Gabitto, Jorge [Prairie View A& M University; Tsouris, Costas [ORNL

2010-01-01

Methane gas hydrates in sediments have been studied by several investigators as a possible future energy resource. Recent hydrate reserves have been estimated at approximately 1016?m3 of methane gas worldwide at standard temperature and pressure conditions. In situ dissociation of natural gas hydrate is necessary in order to commercially exploit the resource from the natural-gas-hydrate-bearing sediment. The presence of gas hydrates in sediments dramatically alters some of the normal physical properties of the sediment. These changes can be detected by field measurements and by down-hole logs. An understanding of the physical properties of hydrate-bearing sediments is necessary for interpretation of geophysical data collected in field settings, borehole, and slope stability analyses; reservoir simulation; and production models. This work reviews information available in literature related to the physical properties of sediments containing gas hydrates. A brief review of the physical properties of bulk gas hydrates is included. Detection methods, morphology, and relevant physical properties of gas-hydrate-bearing sediments are also discussed.

Nicotine Dependence, Physical Activity, and Sedentary Behavior among Adult Smokers.

Science.gov (United States)

Loprinzi, Paul D; Walker, Jerome F

2015-03-01

Research has previously demonstrated an inverse association between smoking status and physical activity; however, few studies have examined the association between nicotine dependence and physical activity or sedentary behavior. This study examined the association between nicotine dependence and accelerometer-determined physical activity and sedentary behavior. Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used. A total of 851 adult (≥20 years) smokers wore an accelerometer for ≥4 days and completed the Fagerstrom Test for Nicotine Dependence scale. Regression models were used to examine the association between nicotine dependence and physical activity/sedentary behavior. After adjusting for age, gender, race-ethnicity, poverty level, hypertension, emphysema, bronchitis, body mass index (BMI), cotinine, and accelerometer wear time, smokers 50 + years of age with greater nicotine dependence engaged in more sedentary behavior (β = 11.4, P = 0.02) and less light-intensity physical activity (β = -9.6, P = 0.03) and moderate-to-vigorous physical activity (MVPA; β = -0.14, P = 0.003) than their less nicotine dependent counterparts. Older adults who are more nicotine dependent engage in less physical activity (both MVPA and light-intensity) and more sedentary behavior than their less nicotine dependent counterparts.

Thermal and physical properties of bakery products.

Science.gov (United States)

Baik, O D; Marcotte, M; Sablani, S S; Castaigne, F

2001-07-01

This article reviews the measurement techniques, prediction models, and data on thermo-physical properties of bakery products: specific heat, thermal conductivity, thermal diffusivity, and density. Over the last decade, investigation has focused more on thermo-physical properties of nonbread bakery products. Both commonly used and new measurement techniques for thermo-physical properties reported in the publication are presented with directions for their proper use. Data and prediction models are tabulated for the range of moisture content and temperature of the bakery products.

Physical properties of beryllium oxide - Irradiation effects

International Nuclear Information System (INIS)

Elston, J.; Caillat, R.

1958-01-01

This work has been carried out in view of determining several physical properties of hot-pressed beryllium oxide under various conditions and the change of these properties after irradiation. Special attention has been paid on to the measurement of the thermal conductivity coefficient and thermal diffusivity coefficient. Several designs for the measurement of the thermal conductivity coefficient have been achieved. They permit its determination between 50 and 300 deg. C, between 400 and 800 deg. C. Some measurements have been made above 1000 deg. C. In order to measure the thermal diffusivity coefficient, we heat a perfectly flat surface of a sample in such a way that the heat flux is modulated (amplitude and frequency being adjustable). The thermal diffusivity coefficient is deduced from the variations of temperature observed on several spots. Tensile strength; compressive strength; expansion coefficient; sound velocity and crystal parameters have been also measured. Some of the measurements have been carried out after neutron irradiation. Some data have been obtained on the change of the properties of beryllium oxide depending on the integrated neutron flux. (author) [fr

PETher - Physical Properties of Thermal Water under In-situ-Conditions

Science.gov (United States)

Herfurth, Sarah; Schröder, Elisabeth

2016-04-01

The objective of PETher, a research project funded by the German Federal Ministry for Economic Affairs and Energy (BMWi), is to experimentally determine thermo-physical properties (specific isobaric heat capacity, kinematic viscosity, density and thermal conductivity) of geothermal water in-situ-conditions (pressure, temperature, chemical composition including gas content of the brine) present in geothermal applications. Knowing these thermo-physical properties reduces the uncertainties with respect to estimating the thermal output and therefore the economic viability of the power plant. Up to now, only a limited number of measurements of selected physical properties have been made, usually under laboratory conditions and for individual geothermal plants. In-situ measured parameters, especially in the temperature range of 120°C and higher, at pressures of 20 bar and higher, as well as with a salinity of up to 250 g/l, are sparse to non-existing. Therefore, pure water properties are often used as reference data and for designing the power plant and its components. Currently available numerical models describing the thermo-physical properties are typically not valid for the conditions in geothermal applications and do not consider the substantial influence of the chemical composition of the thermal water. Also, actual geothermal waters have not been subject of detailed measurements systematically performed under operational conditions on a large-scale basis. Owing to the lack of reliable data, a validation of numerical models for investigating geothermal systems is not possible. In order to determine the dependency of the thermo-physical properties of geothermal water on temperature, pressure and salinity in-situ measurements are conducted. The measurements are taking place directly at several geothermal applications located in Germany's hydrogeothermal key regions. In order to do this, a mobile testing unit was developed and refined with instruments specifically

Dependence of Nanoparticle Toxicity on Their Physical and Chemical Properties

Science.gov (United States)

Sukhanova, Alyona; Bozrova, Svetlana; Sokolov, Pavel; Berestovoy, Mikhail; Karaulov, Alexander; Nabiev, Igor

2018-02-01

Studies on the methods of nanoparticle (NP) synthesis, analysis of their characteristics, and exploration of new fields of their applications are at the forefront of modern nanotechnology. The possibility of engineering water-soluble NPs has paved the way to their use in various basic and applied biomedical researches. At present, NPs are used in diagnosis for imaging of numerous molecular markers of genetic and autoimmune diseases, malignant tumors, and many other disorders. NPs are also used for targeted delivery of drugs to tissues and organs, with controllable parameters of drug release and accumulation. In addition, there are examples of the use of NPs as active components, e.g., photosensitizers in photodynamic therapy and in hyperthermic tumor destruction through NP incorporation and heating. However, a high toxicity of NPs for living organisms is a strong limiting factor that hinders their use in vivo. Current studies on toxic effects of NPs aimed at identifying the targets and mechanisms of their harmful effects are carried out in cell culture models; studies on the patterns of NP transport, accumulation, degradation, and elimination, in animal models. This review systematizes and summarizes available data on how the mechanisms of NP toxicity for living systems are related to their physical and chemical properties.

Structural Dependence of Physical Properties in Sodium Boroaluminosilicate Glasses

DEFF Research Database (Denmark)

Zheng, Qiuju; Potuzak, Marcel; Mauro, John C.

Boroaluminosilicate glasses have found applications in many fields. The extent and nature of the mixing of network formers like SiO2, B2O3, and Al2O3 play an important role in controlling the macroscopic properties. To understand the structure-property correlations in these glasses, we study...... a series of sodium boroaluminosilicate glasses with various [Al2O3]/[SiO2] ratios to access different regimes of sodium behavior. We determine dynamic properties, elastic moduli, and hardness of these glasses. The results reveal an existence of local minimum for density, fragility index, Young’s and shear...

Physical Properties of the MER and Beagle II Landing Sites on Mars

Science.gov (United States)

Jakosky, B. M.; Pelkey, S. M.; Mellon, M. T.; Putzig, N.; Martinez-Alonso, S.; Murphy, N.; Hynek, B.

2003-12-01

The ESA Beagle II and the NASA Mars Exploration Rover spacecraft are scheduled to land on the martian surface in December 2003 and January 2004, respectively. Mission operations and success depends on the physical properties of the surfaces on which they land. Surface structural characteristics such as the abundances of loose, unconsolidated fine material, of fine material that has been cemented into a duricrust, and of rocks affect the ability to safely land and to successfully sample and traverse the surface. Also, physical properties affect surface and atmospheric temperatures, which affect lander and rover functionality. We are in the process of analyzing surface temperature information for these sites, derived from MGS TES and Odyssey THEMIS daytime and nighttime measurements. Our approach is to: (i) remap thermal inertia using TES data at ~3-km resolution, to obtain the most complete coverage possible; (ii) interpret physical properties from TES coverage in conjunction with other remote-sensing data sets; (iii) map infrared brightness using daytime and nighttime THEMIS data at 100-m resolution, and do qualitative analysis of physical properties and processes; and (iv) derive thermal inertia from THEMIS nighttime data in conjunction with daytime albedo measurements derived from TES, THEMIS, and MOC observations. In addition, we will use measured temperatures and derived thermal inertia to predict surface temperatures for the periods of the missions.

Protocol dependence of mechanical properties in granular systems.

Science.gov (United States)

Inagaki, S; Otsuki, M; Sasa, S

2011-11-01

We study the protocol dependence of the mechanical properties of granular media by means of computer simulations. We control a protocol of realizing disk packings in a systematic manner. In 2D, by keeping material properties of the constituents identical, we carry out compaction with various strain rates. The disk packings exhibit the strain rate dependence of the critical packing fraction above which the pressure becomes non-zero. The observed behavior contrasts with the well-studied jamming transitions for frictionless disk packings. We also observe that the elastic moduli of the disk packings depend on the strain rate logarithmically. Our results suggest that there exists a time-dependent state variable to describe macroscopic material properties of disk packings, which depend on its protocol.

Stereology application in the investigation of physical and mechanical properties of porous materials

International Nuclear Information System (INIS)

Cytermann, Richard.

1979-04-01

The sintering of carbonyl nickel powders has been studied through stereology (quantitative microscopy) associated with different physical and mechanical measurements. This study demonstrated that a set of stereological parameters, such as porosity, grain size, mean pore volume ..., was necessary to characterize porous parts with the same porosity obtained through different ways. On the one hand, stereology permitted to elucidate powder shape and speed of pressure rising influence on the compacting process. On the other hand, the study of physical and mechanical properties related to their microstructure led to distinguish: properties such as elasticity modulus independant of compacting pressure, sintering temperature and powder shape. Their evolution has been characterized through contiguity coefficient; properties such as tensile strength dependant of sintering parameters. Their characterization required the simultaneous measurement of porosity mean pore volume, shape factor and grain size [fr

Levels of physical dependence on tobacco among adolescent smokers in Cyprus.

Science.gov (United States)

Christophi, Costas A; Pampaka, Despina; Paisi, Martha; Ioannou, Solonas; DiFranza, Joseph R

2016-09-01

The purpose of this study is to assess tobacco dependence among Cypriot adolescents and examine its association to cigarette consumption and attitudes towards smoking. The current study used cross-sectional data from the 2011 Cyprus Global Youth Tobacco Survey which adopted multistage cluster sampling methods to select adolescents registered in middle and high schools in Cyprus. Tobacco use, physical dependence on tobacco, and attitudes towards tobacco use were measured in 187 adolescents aged 13-18years old who reported that they had smoked at least once in the preceding 30days. Physical dependence was assessed using the Levels of Physical Dependence scale. Physical dependence was present in 86% of the adolescent smokers. The mean latency to needing among smokers in the highest dependence group was 101h. Significant associations were observed between physical dependence and the perceived difficulty in quitting (OR=13.1, 95% CI: 4.0, 43.0) as well as the expectation to continue smoking for the next five years (OR=3.3, 95% CI: 1.3, 8.4). Significant associations were also observed between physical dependence and the number of smoking days per month, daily smoking, daily cigarette consumption, lifetime cigarette consumption, and perceived difficulty in abstaining from smoking for one week. Physical dependence provides a symptom-based approach to assess dependence and it is a strong predictor of adolescents' perceptions of their ability to quit or to refrain from smoking for a week. Physical dependence on tobacco was highly prevalent among adolescent smokers in Cyprus and it was associated with greater perceived difficulty in quitting. Interventions targeting adolescent smoking must account for the high prevalence of physical dependence. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Girdler-sulfide process physical properties

International Nuclear Information System (INIS)

Neuburg, H.J.; Atherley, J.F.; Walker, L.G.

1977-05-01

Physical properties of pure hydrogen sulfide and of gaseous and liquid solutions of the H 2 S-H 2 O system have been formulated. Tables for forty-nine different properties in the pressure and temperature range of interest to the Girdler-Sulfide (GS) process for heavy water production are given. All properties are presented in SI units. A computer program capable of calculating properties of the pure components as well as gaseous mixtures and liquid solutions at saturated and non-saturated conditions is included. (author)

Dependence creating properties of lipotropin C-fragment (β-endorphin): Evidence for its internal control of behavior

NARCIS (Netherlands)

Ree, J.M. van; Smyth, D.G.; Colpaert, F.C.

1979-01-01

The C-fragment of lipotropin (β-endorphin) possesses reinforcing properties, in that this peptide, like heroin, induced intraventricular self-administering behavior in drug naive rats. Only mild behavioral signs reminiscent of physical dependence were present. After injection into the nucleus raphé

Physical Properties of Umbral Dots Observed in Sunspots: A Hinode Observation

Science.gov (United States)

Yadav, Rahul; Mathew, Shibu K.

2018-04-01

Umbral dots (UDs) are small-scale bright features observed in the umbral part of sunspots and pores. It is well established that they are manifestations of magnetoconvection phenomena inside umbrae. We study the physical properties of UDs in different sunspots and their dependence on decay rate and filling factor. We have selected high-resolution, G-band continuum filtergrams of seven sunspots from Hinode to study their physical properties. We have also used Michelson Doppler Imager (MDI) continuum images to estimate the decay rate of selected sunspots. An identification and tracking algorithm was developed to identify the UDs in time sequences. The statistical analysis of UDs exhibits an averaged maximum intensity and effective diameter of 0.26 I_{QS} and 270 km. Furthermore, the lifetime, horizontal speed, trajectory length, and displacement length (birth-death distance) of UDs are 8.19 minutes, 0.5 km s-1, 284 km, and 155 km, respectively. We also find a positive correlation between intensity-diameter, intensity-lifetime, and diameter-lifetime of UDs. However, UD properties do not show any significant relation with the decay rate or filling factor.

Stages of physical dependence in New Zealand smokers: Prevalence and correlates.

Science.gov (United States)

Walton, Darren; Newcombe, Rhiannon; Li, Judy; Tu, Danny; DiFranza, Joseph R

2016-12-01

Physically dependent smokers experience symptoms of wanting, craving or needing to smoke when too much time has passed since the last cigarette. There is interest in whether wanting, craving and needing represent variations in the intensity of a single physiological parameter or whether multiple physiological processes may be involved in the developmental progression of physical dependence. Our aim was to determine how a population of cigarette smokers is distributed across the wanting, craving and needing stages of physical dependence. A nationwide survey of 2594 New Zealanders aged 15years and over was conducted in 2014. The stage of physical dependence was assessed using the Levels of Physical Dependence measure. Ordinal logistic regression analysis was used to assess relations between physical dependence and other variables. Among 590 current smokers (weighted 16.2% of the sample), 22.3% had no physical dependence, 23.5% were in the Wanting stage, 14.4% in the Craving stage, and 39.8% in the Needing stage. The stage of physical dependence was predicted by daily cigarette consumption, and the time to first cigarette, but not by age, gender, ethnicity or socioeconomic status. Fewer individuals were in the craving stage than either the wanting or needing stages. The resulting inverted U-shaped curve with concentrations at either extreme is difficult to explain as a variation of a single biological parameter. The data support an interpretation that progression through the stages of wanting, craving and needing may involve more than one physiological process. Physical dependence to tobacco develops through a characteristic sequence of wanting, craving and needing which correspond to changes in addiction pathways in the brain. It is important to neuroscience research to determine if the development of physical dependence involves changes in a single brain process, or multiple processes. Our data suggests that more than one physiologic process is involved in the

Waste Feed Evaporation Physical Properties Modeling

International Nuclear Information System (INIS)

Daniel, W.E.

2003-01-01

This document describes the waste feed evaporator modeling work done in the Waste Feed Evaporation and Physical Properties Modeling test specification and in support of the Hanford River Protection Project (RPP) Waste Treatment Plant (WTP) project. A private database (ZEOLITE) was developed and used in this work in order to include the behavior of aluminosilicates such a NAS-gel in the OLI/ESP simulations, in addition to the development of the mathematical models. Mathematical models were developed that describe certain physical properties in the Hanford RPP-WTP waste feed evaporator process (FEP). In particular, models were developed for the feed stream to the first ultra-filtration step characterizing its heat capacity, thermal conductivity, and viscosity, as well as the density of the evaporator contents. The scope of the task was expanded to include the volume reduction factor across the waste feed evaporator (total evaporator feed volume/evaporator bottoms volume). All the physical properties were modeled as functions of the waste feed composition, temperature, and the high level waste recycle volumetric flow rate relative to that of the waste feed. The goal for the mathematical models was to predict the physical property to predicted simulation value. The simulation model approximating the FEP process used to develop the correlations was relatively complex, and not possible to duplicate within the scope of the bench scale evaporation experiments. Therefore, simulants were made of 13 design points (a subset of the points used in the model fits) using the compositions of the ultra-filtration feed streams as predicted by the simulation model. The chemistry and physical properties of the supernate (the modeled stream) as predicted by the simulation were compared with the analytical results of experimental simulant work as a method of validating the simulation software

Field dependence-independence and participation in physical activity by college students.

Science.gov (United States)

Liu, Wenhao

2006-06-01

Field-independent individuals, compared with field-dependent individuals, have higher sports potential and advantages in sport-related settings. Little research, however, has been conducted on the association of field dependence-independence and participation in physical activity. The study examined this association for college students who participated in physical activities in and beyond physical education classes. The Group Embedded Figures Test distinguished 40 field-dependent from 40 field-independent participants. Activity logs during one semester showed that field-independent participants were significantly more physically active and their physical activity behaviors were more sport-related than those of field-dependent participants.

Effect of magnetic field on the physical properties of water

Science.gov (United States)

Wang, Youkai; Wei, Huinan; Li, Zhuangwen

2018-03-01

In this study, the effect of magnetic field (MF) on the partial physical properties of water are reported, tap water (TW) and 4 types of magnetized water (MW) were measured in the same condition. It was found that the properties of TW were changed following the MF treatment, shown as the increase of evaporation amount, the decrease of specific heat and boiling point after magnetization, the changes depend on the magnetization effect. In addition, magnetic field strength (MFS) has a marked influence on the magnetization effect, the optimal magnetizing condition was determined as the MFS of 300 mT. The findings of this study offered a facile approach to improve cooling and power generation efficiency in industrial.

Physical properties of organic soils. Chapter 5.

Science.gov (United States)

Elon S. Verry; Don H. Boelter; Juhani Paivanen; Dale S. Nichols; Tom Malterer; Avi Gafni

2011-01-01

Compared with research on mineral soils, the study of the physical properties of organic soils in the United States is relatively new. A comprehensive series of studies on peat physical properties were conducted by Don Boelter (1959-1975), first at the Marcell Experimental Forest (MEF) and later throughout the northern Lakes States to investigate how to express bulk...

A unified dislocation density-dependent physical-based constitutive model for cold metal forming

Science.gov (United States)

Schacht, K.; Motaman, A. H.; Prahl, U.; Bleck, W.

2017-10-01

Dislocation-density-dependent physical-based constitutive models of metal plasticity while are computationally efficient and history-dependent, can accurately account for varying process parameters such as strain, strain rate and temperature; different loading modes such as continuous deformation, creep and relaxation; microscopic metallurgical processes; and varying chemical composition within an alloy family. Since these models are founded on essential phenomena dominating the deformation, they have a larger range of usability and validity. Also, they are suitable for manufacturing chain simulations since they can efficiently compute the cumulative effect of the various manufacturing processes by following the material state through the entire manufacturing chain and also interpass periods and give a realistic prediction of the material behavior and final product properties. In the physical-based constitutive model of cold metal plasticity introduced in this study, physical processes influencing cold and warm plastic deformation in polycrystalline metals are described using physical/metallurgical internal variables such as dislocation density and effective grain size. The evolution of these internal variables are calculated using adequate equations that describe the physical processes dominating the material behavior during cold plastic deformation. For validation, the model is numerically implemented in general implicit isotropic elasto-viscoplasticity algorithm as a user-defined material subroutine (UMAT) in ABAQUS/Standard and used for finite element simulation of upsetting tests and a complete cold forging cycle of case hardenable MnCr steel family.

Physical properties of smectic C liquid crystal cells

International Nuclear Information System (INIS)

Dunn, P.E.

1998-01-01

The aim of this work was to investigate some of the fundamental physical properties of surface stabilised ferroelectric liquid crystal devices (SSFLCDs) using optical, electrical and x-ray diffraction techniques. The measured physical parameters are then related to the performance of display devices. Refractometry measurements on homeotropically aligned FLC samples are used to accurately determine the smectic cone angle and information is also gained on FLC biaxial order. Propagation of optically excited guided modes along liquid crystalline layers is then used to obtain detailed director configuration information. Wavelength dependent extinction angle spectroscopy is also used to extract smectic C director profiles, albeit with a slightly lower accuracy than the guided mode method. A triangular director profile model is found to describe the wavelength dependent extinction angle properties of achiral samples, and examination of the cell spacing dependence of the director profile enables a ratio of bulk elasticity to surface anchoring energy to be determined. Information is obtained on the behaviour of smectic C materials under high frequency electric fields using a continuum director profile model, providing a novel measurement of bend and splay elastic constants. Additionally an extension of the wavelength dependent extinction angle technique allows half splayed states to be characterised. A variety of simple electro-optic techniques are used to characterise several key material parameters. Polarisation reversal current is used to measure both the spontaneous polarisation and an effective FLC switching viscosity. Monochromatic extinction angle measurements under applied d.c. fields are used to determine the cone and layer tilt angles, whilst a comparison of d.c. and a.c. extinction angle characteristics provides an estimate of the dielectric biaxiality. An automated measurement technique is used to determine FLC response time characteristics, which are described

Physical properties of smectic C liquid crystal cells

Energy Technology Data Exchange (ETDEWEB)

Dunn, P E

1998-07-01

The aim of this work was to investigate some of the fundamental physical properties of surface stabilised ferroelectric liquid crystal devices (SSFLCDs) using optical, electrical and x-ray diffraction techniques. The measured physical parameters are then related to the performance of display devices. Refractometry measurements on homeotropically aligned FLC samples are used to accurately determine the smectic cone angle and information is also gained on FLC biaxial order. Propagation of optically excited guided modes along liquid crystalline layers is then used to obtain detailed director configuration information. Wavelength dependent extinction angle spectroscopy is also used to extract smectic C director profiles, albeit with a slightly lower accuracy than the guided mode method. A triangular director profile model is found to describe the wavelength dependent extinction angle properties of achiral samples, and examination of the cell spacing dependence of the director profile enables a ratio of bulk elasticity to surface anchoring energy to be determined. Information is obtained on the behaviour of smectic C materials under high frequency electric fields using a continuum director profile model, providing a novel measurement of bend and splay elastic constants. Additionally an extension of the wavelength dependent extinction angle technique allows half splayed states to be characterised. A variety of simple electro-optic techniques are used to characterise several key material parameters. Polarisation reversal current is used to measure both the spontaneous polarisation and an effective FLC switching viscosity. Monochromatic extinction angle measurements under applied d.c. fields are used to determine the cone and layer tilt angles, whilst a comparison of d.c. and a.c. extinction angle characteristics provides an estimate of the dielectric biaxiality. An automated measurement technique is used to determine FLC response time characteristics, which are described

Physical and psychological nicotine dependence in Greeks: an epidemiological study.

Science.gov (United States)

Margaritis, Vasileios; Mamai-Homata, Eleni

2010-01-01

Smoking is the most widespread addictive behaviour in the world, as it causes physical and psychological dependence on nicotine. The objective of the present study was to discern the prevalence and the relative risks of nicotine dependence of adult people in Athens, Greece, as this country holds first place in cigarette consumption in the European Union. A random sample of 202 current smokers (82 men and 120 women) was drawn from residents aged v 18 years in Athens, the capital of Greece. A questionnaire on the physical (Fagerstrom Test of Nicotine Dependence) and psychological (American Psychiatric Association's diagnostic criteria of nicotine abuse) nicotine dependence was used. According to the results of the present study, 12.4% of the sample reported null physical nicotine dependence, and 31.7% had low, 25.7% had moderate and 30.2% had high nicotine dependence. Multiple logistic regression analysis revealed that younger people (aged 18 to 24 and 25 to 34, odds ratio [OR] = 0.047, P physical dependence. Women tended to be systematically less dependent than men (25% and 37.8% high dependence, respectively). Furthermore, 75.7% of the sample had psychological nicotine dependence. Binary logistic regression analysis and chi-square test revealed that younger people (18- to 24-year-olds, OR = 0.081, P dependence. In addition, women showed a higher percentage of withdrawal symptoms compared with men (80% and 68%, respectively). The results of the present study provided compelling evidence that physical and, in particular, psychological nicotine dependence of adult people in Athens, Greece, was significant, and this calls for a course of action that should be taken by public health policy-makers to reduce smoke consumption.

Agroclimatic mapping of maize crop based on soil physical properties

International Nuclear Information System (INIS)

Dourado Neto, Durval; Sparovek, G.; Reichardt, K.; Timm, Luiz Carlos; Nielsen, D.R.

2004-01-01

With the purpose of estimating water deficit to forecast yield knowing productivity (potential yield), the water balance is useful tool to recommend maize exploration and to define the sowing date. The computation can be done for each region with the objective of mapping maize grain yield based on agro-climatic data and soil physical properties. Based on agro-climatic data, air temperature and solar radiation, a model was built to estimate the corn grain productivity (the energy conversion results in dry mass production). The carbon dioxide (CO 2 ) fixation by plants is related to gross carbohydrate (CH 2 O) production and solar radiation. The CO 2 assimilation by C4 plants depends on the photosynthetic active radiation and temperature. From agro-climatic data and soil physical properties, a map with region identification can be built for solar radiation, air temperature, rainfall, maize grain productivity and yield, potential and real evapo-transpiration and water deficit. The map allows to identify the agro-climatic and the soil physical restrictions. This procedure can be used in different spatial (farm to State) and temporal (daily to monthly data) scales. The statistical analysis allows to compare estimated and observed values in different situations to validate the model and to verify which scale is more appropriate

Physical-chemical property based sequence motifs and methods regarding same

Science.gov (United States)

Braun, Werner [Friendswood, TX; Mathura, Venkatarajan S [Sarasota, FL; Schein, Catherine H [Friendswood, TX

2008-09-09

A data analysis system, program, and/or method, e.g., a data mining/data exploration method, using physical-chemical property motifs. For example, a sequence database may be searched for identifying segments thereof having physical-chemical properties similar to the physical-chemical property motifs.

40 CFR 716.50 - Reporting physical and chemical properties.

Science.gov (United States)

2010-07-01

... chemical properties. Studies of physical and chemical properties must be reported under this subpart if... they investigated one or more of the following properties: (a) Water solubility. (b) Adsorption... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reporting physical and chemical...

Physical Properties of Liquid Crystals

CERN Document Server

Gray, George W; Spiess, Hans W

1999-01-01

This handbook is a unique compendium of knowledge on all aspects of the physics of liquid crystals. In over 500 pages it provides detailed information on the physical properties of liquid crystals as well as the recent theories and results on phase transitions, defects and textures of different types of liquid crystals. An in-depth understanding of the physical fundamentals is a prerequisite for everyone working in the field of liquid crystal research. With this book the experts as well as graduate students entering the field get all the information they need.

F-Canyon Sludge Physical Properties

International Nuclear Information System (INIS)

Poirier, M. R.; Hansen, P. R.; Fink, S. D.

2005-01-01

The Site Deactivation and Decommissioning (SDD) Organization is evaluating options to disposition the 800 underground tanks (including removal of the sludge heels from these tanks). To support this effort, DandD requested assistance from Savannah River National Laboratory (SRNL) personnel to determine the pertinent physical properties to effectively mobilize the sludge from these tanks (Tanks 804, 808, and 809). SDD provided SRNL with samples of the sludge from Tanks 804, 808, and 809. The authors measured the following physical properties for each tank: particle settling rate, shear strength (i.e., settled solids yield stress), slurry rheology (i.e., yield stress and consistency), total solids concentration in the sludge, soluble solids concentration of the sludge, sludge density, and particle size distribution

Physical Properties of Moringa ( Moringa oleifera ) Seeds in relation ...

African Journals Online (AJOL)

Physical properties are very important in the design and manufacturing of processing machines. In this research work, the physical properties of Moringa were determined as design parameters for the development of an oil expeller for the crop. The properties were: length, width, thickness, arithmetic and geometric ...

Temperature dependence of nuclear surface properties

International Nuclear Information System (INIS)

Campi, X.; Stringari, S.

1982-01-01

Thermal properties of nuclear surface are investigated in a semi-infinite medium. Explicit analytical expression are given for the temperature dependence of surface thickness, surface energy and surface free energy. In this model the temperature effects depend critically on the nuclear incompressibility and on the shape of the effective mass at the surface. To illustrate the relevance of these effects we made an estimate of the temperature dependence of the fission barrier height. (orig.)

SPATIAL CORRELATION BETWEEN PHYSICAL PROPERTIES OF SOIL AND WEEDS IN TWO MANAGEMENT SYSTEMS

Directory of Open Access Journals (Sweden)

Valter Roberto Schaffrath

2015-02-01

Full Text Available The spatial correlation between soil properties and weeds is relevant in agronomic and environmental terms. The analysis of this correlation is crucial for the interpretation of its meaning, for influencing factors such as dispersal mechanisms, seed production and survival, and the range of influence of soil management techniques. This study aimed to evaluate the spatial correlation between the physical properties of soil and weeds in no-tillage (NT and conventional tillage (CT systems. The following physical properties of soil and weeds were analyzed: soil bulk density, macroporosity, microporosity, total porosity, aeration capacity of soil matrix, soil water content at field capacity, weed shoot biomass, weed density, Commelina benghalensis density, and Bidens pilosa density. Generally, the ranges of the spatial correlations were higher in NT than in CT. The cross-variograms showed that many variables have a structure of combined spatial variation and can therefore be mapped from one another by co-kriging. This combined variation also allows inferences about the physical and biological meanings of the study variables. Results also showed that soil management systems influence the spatial dependence structure significantly.

Haloperidol Disrupts Opioid-Antinociceptive Tolerance and Physical Dependence

Science.gov (United States)

Yang, Cheng; Chen, Yan; Tang, Lei

2011-01-01

Previous studies from our laboratory and others have implicated a critical role of Ca2+/calmodulin-dependent protein kinase II (CaMKII) in opioid tolerance and dependence. Translational research targeting the CaMKII pathway is challenging, if not impossible, because of a lack of selective inhibitors. We discovered in a preliminary study that haloperidol, a butyrophenone antipsychotic drug, inhibited CaMKII, which led us to hypothesize that haloperidol can attenuate opioid tolerance and dependence by inhibiting CaMKII. The hypothesis was tested in two rodent models of opioid tolerance and dependence. Pretreatment with haloperidol (0.2–1.0 mg/kg i.p.) prevented the development of morphine tolerance and dependence in a dose-dependent manner. Short-term treatment with haloperidol (0.06–0.60 mg/kg i.p.) dose-dependently reversed the established morphine-antinociceptive tolerance and physical dependence. Correlating with behavioral effects, pretreatment or short-term treatment with haloperidol dose-dependently inhibited morphine-induced up-regulation of supraspinal and spinal CaMKIIα activity. Moreover, haloperidol given orally was also effective in attenuating morphine-induced CaMKIIα activity, antinociceptive tolerance, and physical dependence. Taken together, these data suggest that haloperidol attenuates opioid tolerance and dependence by suppressing CaMKII activity. Because haloperidol is a clinically used drug that can be taken orally, we propose that the drug may be of use in attenuating opioid tolerance and dependence. PMID:21436292

Nicotine dependence, physical activity, and sedentary behavior among adult smokers

OpenAIRE

Paul D Loprinzi; Jerome F Walker

2015-01-01

Background: Research has previously demonstrated an inverse association between smoking status and physical activity; however, few studies have examined the association between nicotine dependence and physical activity or sedentary behavior. Aim: This study examined the association between nicotine dependence and accelerometer-determined physical activity and sedentary behavior. Materials and Methods: Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used....

Physical properties of five grain dust types.

OpenAIRE

Parnell, C B; Jones, D D; Rutherford, R D; Goforth, K J

1986-01-01

Physical properties of grain dust derived from five grain types (soybean, rice, corn, wheat, and sorghum) were measured and reported. The grain dusts were obtained from dust collection systems of terminal grain handling facilities and were assumed to be representative of grain dust generated during the handling process. The physical properties reported were as follows: particle size distributions and surface area measurements using a Coulter Counter Model TAII; percent dust fractions less tha...

Physical properties of sunflower grains after drying

Directory of Open Access Journals (Sweden)

Paulo Carteri Coradi

2015-12-01

Full Text Available The knowledge of the physical properties of the grains is important for the optimization of post-harvest operations. This study aimed to evaluate the effects of convective drying with different air temperatures (45, 55, 65 and 75 °C the physical properties of sunflower seeds. The drying sunflower grains was performed in convection oven with forced air. In natural conditions, samples of 5 kg of pellets were used for each repetition drying. During the drying process, the grains samples were weighed periodically until they reach 10% (wet basis, w.b., then were subjected to evaluations of physical properties. According to the results it was observed that the porosity, apparent density, thousand kernel weight to the drag coefficient, roundness, sphericity and width of sunflower seed did not change with increasing temperature drying air. It was concluded that the drying air temperatures of 45 °C and 55 retained the initial physical characteristics of sunflower seeds. The temperature of the drying air of 75 °C had greater influence on changes in volumetric shrinkage of the grains.

Electroweak properties of particle physics. Volume 2

International Nuclear Information System (INIS)

Aleksan, R.; Ellis, N.; Falvard, A.; Fayard, L.; Frere, J.M.; Kuehn, J.H.; Le Yaouanc, A.; Roudeau, P.; Wormser, G.

1991-01-01

The 23th GIf school was held at Ecole Polytechnique, Palaiseau, France from 16 to 20 September 1991. The subject was large: Electroweak properties of heavy quarks. The second part has been devoted to B physics at hadron machines, search for Top, Charm particle physics and Quarkonium physics

Isospin dependent properties of asymmetric nuclear matter

OpenAIRE

Chowdhury, P. Roy; Basu, D. N.; Samanta, C.

2009-01-01

The density dependence of nuclear symmetry energy is determined from a systematic study of the isospin dependent bulk properties of asymmetric nuclear matter using the isoscalar and the isovector components of density dependent M3Y interaction. The incompressibility $K_\\infty$ for the symmetric nuclear matter, the isospin dependent part $K_{asy}$ of the isobaric incompressibility and the slope $L$ are all in excellent agreement with the constraints recently extracted from measured isotopic de...

Physically unclonable functions constructions, properties and applications

CERN Document Server

Maes, Roel

2013-01-01

Physically unclonable functions (PUFs) are innovative physical security primitives that produce unclonable and inherent instance-specific measurements of physical objects; in many ways they are the inanimate equivalent of biometrics for human beings. Since they are able to securely generate and store secrets, they allow us to bootstrap the physical implementation of an information security system. In this book the author discusses PUFs in all their facets: the multitude of their physical constructions, the algorithmic and physical properties which describe them, and the techniques required to

The physical properties of glycerin

International Nuclear Information System (INIS)

Kimsanov, B.Kh.; Karimov, M.B.; Khuseynov, K.

1998-01-01

In this chapter of book authors describe physical properties of glycerin. The pure glycerin presents syrup-vivid insipid transparent solution odorless and sweet on taste. The glycerin is very hygroscopic and can absorb from air till 40% moisture against its mass

Context-dependent utility overrides absolute memory as a determinant of choice.

Science.gov (United States)

Pompilio, Lorena; Kacelnik, Alex

2010-01-05

A core problem of decision theories is that although decisionmakers' preferences depend on learning, their choices could be driven either by learned representations of the physical properties of each alternative (for instance reward sizes) or of the benefit (utility and fitness) experienced from them. Physical properties are independent of the subject's state and context, but utility depends on both. We show that starlings' choices are better explained by memory for context-dependent utility than by representations of the alternatives' physical properties, even when the decisionmakers' state is controlled and they have accurate knowledge about the options' physical properties. Our results support the potential universality of utility-driven preference control.

SIFAT FISIK MINYAK SAWIT KASAR DAN KORELASINYA DENGAN ATRIBUT MUTU [Physical Properties of Crude Palm Oil and Their Correlations to the Quality Attributes

Directory of Open Access Journals (Sweden)

Nur Wulandari1,2*

2011-12-01

Full Text Available Indonesia is the largest producer and exporter of crude palm oil (CPO in the world. Process engineering applications of CPO during handling, transporting, and processing, need baseline data related to CPO’s physical properties. This research was aimed to obtain baseline data about physical properties of CPO and to study the correlation between CPO’s quality attributes to their physical property parameters. Study on physical property and quality of CPO was conducted to five CPO samples from different CPO’s producers. Those samples had variations on physical property parameters and quality attributes. Some physical property parameters of CPO were depended on the temperature of measurements. CPO samples showed non-Newtonian pseudoplastic behaviour at 25°C with various flow behaviour index (n and concistency index (K, other wise at 55°C all CPO samples showed Newtonian behaviour.There were good correlations between quality attributes of CPO to their physical property parameters at 25°C, including correlations between free fatty acid contents of CPO and the temperatures of crystallization, as well as between iodine values and the rheological properties of CPO.

Physical and Frictional Properties of NERICA

Directory of Open Access Journals (Sweden)

2016-11-01

Full Text Available Some physical and frictional properties of the seeds and husks of New Rice for Africa (NERICA were studied at varying moisture contents of 13%, 17%, and 20% (w.b. In the study, four varieties of NERICA namely; FARO 44, FARO 51, FARO 52 and FARO 57 were selected to represent the different size ranges common to NERICA. The physical properties of NERICA such as shape, size, volume, moisture contents, density, weights, surface area, aspect ratio and sphericity were obtained through physical measurement of the grains samples of each of the four varieties. Results of the physical measurements indicate that the size ranges for the varieties are as follows: FARO 44; 3.653mm to 3.858mm, FARO 51; 3.685mm to 3.916mm, FARO 52; 3.674mm to 3.863mm and FARO 57; 3.924mm to 4.019mm. Results of the frictional properties, shows that plywood material has the highest value of 28.4(1.36 = 33.0(1.41, 29.9(1.38 = 35.2(1.45 and 30.4(1.28 = 37.6(1.51 at 13%, 17% and 20% (w.b respectively, while plastic material has the lowest coefficient of friction value of 20.8(1.21 = 17.7(1.14, 19.4(1.17 = 21.8(1.24 and 21.3(1.24 = 22.9(1.26 at 13%, 17% and 20% (w.b respectively.

Physical properties of five grain dust types.

Science.gov (United States)

Parnell, C B; Jones, D D; Rutherford, R D; Goforth, K J

1986-01-01

Physical properties of grain dust derived from five grain types (soybean, rice, corn, wheat, and sorghum) were measured and reported. The grain dusts were obtained from dust collection systems of terminal grain handling facilities and were assumed to be representative of grain dust generated during the handling process. The physical properties reported were as follows: particle size distributions and surface area measurements using a Coulter Counter Model TAII; percent dust fractions less than 100 micron of whole dust; bulk density; particle density; and ash content. PMID:3709482

Moisture-Dependent Physical Properties of Àbèèrè (Picralima nitida Seeds

Directory of Open Access Journals (Sweden)

A. K. Aremu

2015-08-01

Full Text Available Some relevant engineering properties of Àbèèrè (Picralima nitida seeds are needed for the design of its processing equipments. The geometric, gravimetric and frictional properties of Àbèèrè seed in the moisture content ranges of 7.98% - 47.77% (wb were investigated. The average length, width, thickness, arithmetic and geometric mean diameters, sphericity, surface area, volume, true and bulk densities and angles of repose increased from 28.76 – 30.75mm, 16.18 – 19.62mm, 5.75 – 7.15mm, 16.90 – 19.17mm, 13.81 – 16.11mm,0.48 – 0.53, 600.94 – 817.83mm2, 443.00 – 717.92mm3, 2.49×10-3 – 2.60×10-3g/mm3, 1.14×10-3 – 1.50×10-3g/mm3and 27.97o – 30.26o respectively as the moisture content increased from 7.98% to 47.77%. However, values for porosity decreased from 0.54 – 0.42. The static coefficient of friction of Àbèèrè increased linearly over the three material surfaces – plywood, stainless steel and glass – with increasing moisture content from 0.445 – 0.468, 0.286 – 0.384 and 0.357 – 0.389 respectively. The steel surface had the lowest static coefficient of friction whereas the plywood gave the highest value at all moisture content levels. The regression models developed for all the physical properties of the seeds had high coefficient of determination, R2.

Propagation in a waveguide with range-dependent seabed properties.

Science.gov (United States)

Holland, Charles W

2010-11-01

The ocean environment contains features affecting acoustic propagation that vary on a wide range of time and space scales. A significant body of work over recent decades has aimed at understanding the effects of water column spatial and temporal variability on acoustic propagation. Much less is understood about the impact of spatial variability of seabed properties on propagation, which is the focus of this study. Here, a simple, intuitive expression for propagation with range-dependent boundary properties and uniform water depth is derived. It is shown that incoherent range-dependent propagation depends upon the geometric mean of the seabed plane-wave reflection coefficient and the arithmetic mean of the cycle distance. Thus, only the spatial probability distributions (pdfs) of the sediment properties are required. Also, it is shown that the propagation over a range-dependent seabed tends to be controlled by the lossiest, not the hardest, sediments. Thus, range-dependence generally leads to higher propagation loss than would be expected, due for example to lossy sediment patches and/or nulls in the reflection coefficient. In a few instances, propagation over a range-dependent seabed can be calculated using range-independent sediment properties. The theory may be useful for other (non-oceanic) waveguides.

41 CFR 109-1.5110 - Physical inventories of personal property.

Science.gov (United States)

2010-07-01

...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5110 Physical inventories of... items indicates that this action is necessary for effective property accounting, utilization, or control... property records, and with applicable financial control accounts. (j) The results of physical inventories...

Concentration dependence of physical properties of liquid NaF–LiF–NdF{sub 3} alloys

Energy Technology Data Exchange (ETDEWEB)

Bulavin, L. [Kyiv National Taras Shevchenko University, Faculty of Physics, 2 Glushkova Ave., 03022 Kyiv (Ukraine); Plevachuk, Yu., E-mail: plevachuk@mail.lviv.ua [Ivan Franko National University, Department of Metal Physics, 8 Kyrylo and Mephodiy Street, 79005 Lviv (Ukraine); Sklyarchuk, V. [Ivan Franko National University, Department of Metal Physics, 8 Kyrylo and Mephodiy Street, 79005 Lviv (Ukraine); Omelchuk, A.; Faidiuk, N.; Savchuk, R. [V.I. Vernadsky Institute of General and Inorganic Chemistry, 32/34 prosp. Akad. Palladina, 03680 Kyiv (Ukraine); Shtablavyy, I.; Vus, V. [Ivan Franko National University, Department of Metal Physics, 8 Kyrylo and Mephodiy Street, 79005 Lviv (Ukraine); Yakymovych, A. [Department of Inorganic Chemistry (Materials Chemistry), University of Vienna, Währinger Str. 42, A-1090 Vienna (Austria)

2014-04-01

Highlights: • Molten NaF–LiF–NdF{sub 3} eutectic and peritectic alloys can be used in liquid salt reactors. • A stepped dissociation exists well above melting in the both alloys. • Anomalous properties behaviour proves that a short-range order persists after melting. • Transformation of structure spread to a wide temperature range in the liquid phase. - Abstract: Experimental studies of viscosity, thermoelectric power and electrical conductivity of the ionic liquid alloys NaF–LiF–NdF{sub 3} were carried out in the wide temperature intervals above the melting points. Similar temperature dependences of these properties for different melt compositions have been revealed. The alloy composition has a significant influence on the interval of melt homogeneity and behaviour of the thermoelectric power temperature coefficient. It was found that a small shift from the peritectic to eutectic composition increases considerable the viscosity. A correlation between the structure and thermophysical properties has been analyzed. The results can be used in modelling a blanket for the liquid salt reactor.

Physical properties of liquid sodium

International Nuclear Information System (INIS)

Alberdi Primicia, J.; Martinez Piquer, T.A.

1977-01-01

The molten sodium has been the more accepted coolant for the first generation of FBR, by this reason the knowledge of its technology is needed for the development of the next LMFBR. A series of necessary data for designing sodium liquid systems are given. Tables and graphics about the most important physical sodium properties between 1200-1400 degC are gathered. The results have been obtained from equations that relate the properties with temperature using a Fortran IV program. (author) [es

Fundamentals of semiconductors physics and materials properties

CERN Document Server

Yu, Peter Y

2005-01-01

Provides detailed explanations of the electronic, vibrational, transport, and optical properties of semiconductors. This textbook emphasizes understanding the physical properties of Si and similar tetrahedrally coordinated semiconductors and features an extensive collection of tables of material parameters, figures, and problems.

Swiss Atlas of PHYsical properties of Rocks (SAPHYR)

Science.gov (United States)

Zappone, Alba; Kissling, Eduard

2015-04-01

The Swiss Atlas of PHYsical properties of Rocks (SAPHYR), is a multi-year project, funded entirely by Swiss Commission for Geophysics (SGPK), with the aim to compile a comprehensive data set in digital form on physical properties of rocks exposed in Switzerland and surrounding regions. The ultimate goal of SAPHYR is to make these data accessible to an open and wide public including industrial, engineering, land and resource planning companies, as well as academic institutions, or simply people interested in geology. Since the early sixties worldwide many scientists, i.e. geophysicists, petrologists, and engineers, focused their work on laboratory measurements of rocks physical properties, and their relations with microstructures, mineralogical compositions and other rock parameters, in the effort to constrain the geological interpretation of geophysical surveys. Particularly in the years in which seismic reflection and refraction crustal scale projects were investigating the deep structures of the Alps, laboratories capable to reproduce the pressure and temperature ranges of the continental crust were collecting measurements of various rock parameters on a wide variety of lithologies, developing in the meantime more and more sophisticated experimental methodologies. In recent years, the increasing interest of European Countries on non-traditional energy supply, (i.e. Deep Geothermal Energy and shale gas) and CO2 storage renovated the interests in physical characterization of the deep underground. SAPHYR aims to organize all those laboratory data into a geographically referenced database (GIS). The data refer to density, porosity, permeability, and seismic, magnetic, thermal and electric properties. In the past years, effort has been placed on collecting samples and measuring the physical properties of lithologies that were poorly documented in literature. The phase of laboratory measurements is still in progress. Recently, SAPHYR project focused towards developing

Construction of database server system for fuel thermo-physical properties

International Nuclear Information System (INIS)

Park, Chang Je; Kang, Kwon Ho; Song, Kee Chan

2003-12-01

To perform the evaluation of various fuels in the nuclear reactors, not only the mechanical properties but also thermo-physical properties are required as one of most important inputs for fuel performance code system. The main objective of this study is to make a database system for fuel thermo-physical properties and a PC-based hardware system has been constructed for ease use for the public with visualization such as web-based server system. This report deals with the hardware and software which are used in the database server system for nuclear fuel thermo-physical properties. It is expected to be highly useful to obtain nuclear fuel data without such a difficulty through opening the database of fuel properties to the public and is also helpful to research of development of various fuel of nuclear industry. Furthermore, the proposed models of nuclear fuel thermo-physical properties will be enough utilized to the fuel performance code system

Fundamentals of semiconductors physics and materials properties

CERN Document Server

Yu, Peter Y

2010-01-01

This fourth edition of the well-established Fundamentals of Semiconductors serves to fill the gap between a general solid-state physics textbook and research articles by providing detailed explanations of the electronic, vibrational, transport, and optical properties of semiconductors. The approach is physical and intuitive rather than formal and pedantic. Theories are presented to explain experimental results. This textbook has been written with both students and researchers in mind. Its emphasis is on understanding the physical properties of Si and similar tetrahedrally coordinated semiconductors. The explanations are based on physical insights. Each chapter is enriched by an extensive collection of tables of material parameters, figures, and problems. Many of these problems "lead the student by the hand" to arrive at the results. The major changes made in the fourth edition include: an extensive appendix about the important and by now well-established deep center known as the DX center, additional problems...

SAPHYR: the Swiss Atlas of PHYsical properties of Rocks

Science.gov (United States)

Wenning, Q. C.; Zappone, A. S.; Kissling, E.

2015-12-01

The Swiss Atlas of PHYsical properties of Rocks (SAPHYR) is a multi-year project, aiming to compile a comprehensive data set on physical properties of rocks exposed in Switzerland and surrounding areas. The ultimate goal of SAPHYR is to make these data accessible to an open and wide public, such as industrial, engineering, land and resource planning companies, as well as academic institutions. Since the early sixties worldwide geophysicists, petrologists, and engineers, focused their work on laboratory measurements of rocks physical properties, and their relations with microstructures, mineralogical compositions and other rock parameters, in the effort to constrain the geological interpretation of geophysical surveys. In combination with efforts to investigate deep structure of the continental crust by controlled source seismology, laboratories capable to reproduce pressure and temperature conditions to depth of 50km and more collected measurements of various parameters on a wide variety of rock types. In recent years, the increasing interest on non-traditional energy supply, (deep geothermal energy, shale gas) and CO2 storage renovated the interests in physical characterization of the deep underground. The idea to organize those laboratory data into a geographically referenced database (GIS) is supported by the Swiss Commission for Geophysics. The data refer to density and porosity, seismic, magnetic, thermal properties, permeability and electrical properties. An effort has been placed on collecting samples and measuring the physical properties of lithologies that are poorly documented in literature. The phase of laboratory measurements is still in progress. At present SAPHYR focuses towards developing a 3-D physical properties model of the Swiss subsurface, using the structure of the exposed geology, boreholes data and seismic surveys, combined with lab determined pressure and temperature derivatives. An early version of the final product is presented here.

Temporal dependence of the selectivity property of SES stations in western Greece

Directory of Open Access Journals (Sweden)

E. Dologlou

2009-06-01

Full Text Available The selectivity property of the SES stations, IOA, PIR and PAT in western Greece, based on reported precursory SES signals and associated large earthquakes (M_w≥5.4 that occurred from 1983 to the end of 2008, has been examined. Interesting temporal dependence of the sensitive ability of these stations has been unveiled. Physical mechanisms for the observed changes in selectivity might be related with tectonic and geodynamic events. For instance, selectivity for IOA exhibits a time dependence, for PAT probably is related to the activation of Wadati-Benioff zone while for PIR seems to be related to the specific tectonics of two confined areas such as the Cephalonia Transform Faulting zone in Ionian Sea and the southwestern part of the Hellenic Trench.

Important physical properties of peat materials

Science.gov (United States)

D.H. Boelter

1968-01-01

Peat materials from 12 bogs in northern Minnesota, U.S.A., showed significant differences in physical properties. It is pointed out that 1) these properties can be related to the hydrology of organic soils only if the soils represent undisturbed field conditions, and 2) volumetric expressions of water content are necessary to correctly evaluate the amount of water in a...

Effective moisture diffusivity, moisture sorption, thermo-physical properties and infrared drying kinetics of germinated paddy

Directory of Open Access Journals (Sweden)

Supawan Tirawanichakul

2014-02-01

Full Text Available Temperature and relative humidity (RH dependence of moisture sorption phenomena for agricultural products provide valuable information related to the thermodynamics of the system. So the equilibrium moisture contents (EMC, effective moisture diffusivity (Deff and thermo-physical properties in terms of void fraction, specific heat capacity, and the apparent density of germinated non-waxy Suphanburi 1 paddy were evaluated. Five commonly cited EMC equations were fitted to the experimental data among temperatures of 40-60°C correlating with RH of 0-90%. The results showed that the modified GAB equation was the best function for describing experimental results while those evaluated thermo-physical properties depended on moisture content. To determine drying kinetics model, the simulated values using Midilli et al. (2002 model and Page’s model was the best fitting to exact drying kinetics values for infrared (IR and hot air (HA drying, respectively. Finally, the Deff value of paddy dried with IR and HA sources were also evaluated and the calculated Deff value of both HA and IR drying was in order of 10-9 m2/s.

Nicotine dependence matters: examining longitudinal association between smoking and physical activity among Canadian adults.

Science.gov (United States)

Azagba, Sunday; Asbridge, Mark

2013-11-01

A number of studies point to the inverse relationship between physical activity and smoking; however, none has examined the role of nicotine dependence in physical activity participation among smokers. This study examined whether levels of nicotine dependence modify the association between leisure time physical activity and smoking status. The study used longitudinal data on 6795 adults from the Canadian National Population Health Survey (2004-2010). Generalized estimating equations were used to examine the association between physical activity, smoking, and nicotine dependence. We found that nicotine dependent smokers were significantly less likely to be physically active compared to non-smokers. Specifically, using the Fagerstrom Test for Nicotine Dependence, nicotine dependent smokers (OR 0.65, 95% CI 0.55-0.76) were less likely to be physically active while no significant difference was found for non-dependent smokers (OR 0.90, 95% CI 0.80-1.02) compared to non-smokers. Nicotine dependence matters in shaping engagement in physical activity among daily smokers. Efforts directed at promoting smoking cessation through nicotine dependence treatment intervention may provide additional benefits to health and well-being through an increased participation in physical activity. © 2013.

Physical and chemical properties of calcium doped neodymium manganite

International Nuclear Information System (INIS)

Tikhonova, L.A.; Zhuk, P.P.; Tonoyan, A.A.; Vecher, A.A.

1991-01-01

Physical and chemical properties of calcium doped neodymium manganite were investigated. It was shown that structure of perovskite with O'-orthorhombic distortion was characteristic for solid solutions of Nd 1-x Ca x MnO 3 (x=0-0.5). Maximum of conductivity for samples with x=0.2 was determined. Inversion of conductivity from p- (x=0) to n-type (x=0.5) was observed in increase of concentration of calcium doped addition. Values of thermal expansion coefficient of studied solid solutions of Nd 1-x Ca x MnO 3 didn't depend on concentration of doped addition within the range 700 to 1200 K and were (9.9-11.3)·10 -6 K -1

Thermo-Physical Properties of Selected Inconel

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Krajewski P.K.

2014-10-01

Full Text Available The paper brings results of examinations of main thermo-physical properties of selected Inconel alloys, i.e. their heat diffusivity, thermal conductivity and heat capacity, measured in wide temperature range of 20 – 900 oC. Themathematical relationships of the above properties vs. temperature were obtained for the IN 100 and IN 713C alloys. These data can be used when modelling the IN alloys solidification processes aimed at obtaining required structure and properties as well as when designing optimal work temperature parameters.

Modelling of physical properties - databases, uncertainties and predictive power

DEFF Research Database (Denmark)

Gani, Rafiqul

in the estimated/predicted property values, how to assess the quality and reliability of the estimated/predicted property values? The paper will review a class of models for prediction of physical and thermodynamic properties of organic chemicals and their mixtures based on the combined group contribution – atom......Physical and thermodynamic property in the form of raw data or estimated values for pure compounds and mixtures are important pre-requisites for performing tasks such as, process design, simulation and optimization; computer aided molecular/mixture (product) design; and, product-process analysis...

Temperature dependence of elastic properties of paratellurite

International Nuclear Information System (INIS)

Silvestrova, I.M.; Pisarevskii, Y.V.; Senyushenkov, P.A.; Krupny, A.I.

1987-01-01

New data are presented on the temperature dependence of the elastic wave velocities, elastic stiffness constants, and thermal expansion of paratellurite. It is shown that the external pressure appreciably influences the elastic properties of TeO 2 , especially the temperature dependence of the elastic modulus connected with the crystal soft mode. (author)

IMPROVING PHYSICAL PROPERTIES OF RAPE BIOFUELS

Directory of Open Access Journals (Sweden)

Zbigniew Kiernicki

2012-12-01

Full Text Available The researches on the use of biodiesel and fuel derived from waste plastics are presented in the paper. Biodiesel and fuel obtained from waste plastics were both used as fuel components. FAME is a bio-admixture in the fuel. The catalytic cracking of polyolefin was the source of second fuel admixture. The physical properties of the analyzed components of fuel have been presented. The operational parameters of direct injection in diesel engines fuelled by tested fuel blends was set out. The preparation of the fuel mixture was also described. The concept of the diesel fuel which is made from the components of opposite physical properties could have a positive practical effect and could improve the use of biofuels.

Physical properties and thermoluminescence of glasses designed for radiation dosimetry measurements

International Nuclear Information System (INIS)

Laopaiboon, R.; Bootjomchai, C.

2015-01-01

Highlights: • TL stability of soda-lime glass was corrected by dopants. • D LDL values indicated that the glass samples have good radiation sensitivity. • Bond compression model theory was used to confirm the results from experimental. • High elastic moduli of glass samples indicated that high stability of structure. - Abstract: Soda lime glasses doped with CeO 2 , Nd 2 O 3 and MnO 2 were prepared. Thermoluminescence (TL) properties, such as glow curves and linearity of TL response on irradiation dose were investigated. Results showed that the TL properties depended on the type and concentration of the dopants. Samples were selected to calculate energy trap depth parameters. To design materials for radiation dosimetry, physical properties, ion concentration, elastic properties and effective atomic numbers are important. Theoretical bond compression models were used to determine the elastic moduli for comparison with experimental values. Results show fair agreement between theoretical and experimental measurements. The high elastic moduli of the glass samples indicated high rigidity and stability of the glass matrix structure

Setting semantics: conceptual set can determine the physical properties that capture attention.

Science.gov (United States)

Goodhew, Stephanie C; Kendall, William; Ferber, Susanne; Pratt, Jay

2014-08-01

The ability of a stimulus to capture visuospatial attention depends on the interplay between its bottom-up saliency and its relationship to an observer's top-down control set, such that stimuli capture attention if they match the predefined properties that distinguish a searched-for target from distractors (Folk, Remington, & Johnston, Journal of Experimental Psychology: Human Perception & Performance, 18, 1030-1044 1992). Despite decades of research on this phenomenon, however, the vast majority has focused exclusively on matches based on low-level physical properties. Yet if contingent capture is indeed a "top-down" influence on attention, then semantic content should be accessible and able to determine which physical features capture attention. Here we tested this prediction by examining whether a semantically defined target could create a control set for particular features. To do this, we had participants search to identify a target that was differentiated from distractors by its meaning (e.g., the word "red" among color words all written in black). Before the target array, a cue was presented, and it was varied whether the cue appeared in the physical color implied by the target word. Across three experiments, we found that cues that embodied the meaning of the word produced greater cuing than cues that did not. This suggests that top-down control sets activate content that is semantically associated with the target-defining property, and this content in turn has the ability to exogenously orient attention.

Utilization of turkey manure as granular activated carbon: physical, chemical and adsorptive properties.

Science.gov (United States)

Lima, Isabel; Marshall, Wayne E

2005-01-01

The high availability of large quantities of turkey manure generated from turkey production makes it an attractive feedstock for carbon production. Pelletized samples of turkey litter and cake were converted to granular activated carbons (GACs) by steam activation. Water flow rate and activation time were changed to produce a range of activation conditions. The GACs were characterized for select physical (yield, surface area, bulk density, attrition), chemical (pH, surface charge) and adsorptive properties (copper ion uptake). Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant. Yields varied from 23% to 37%, surface area varied from 248 to 472 m(2)/g and copper ion adsorption varied from 0.72 to 1.86 mmol Cu(2+)/g carbon. Copper ion adsorption greatly exceeded the values for two commercial GACs. GACs from turkey litter and cake show considerable potential to remove metal ions from water.

Temperature and Pressure Dependences of the Elastic Properties of Tantalum Single Crystals Under Tensile Loading: A Molecular Dynamics Study

Science.gov (United States)

Li, Wei-bing; Li, Kang; Fan, Kan-qi; Zhang, Da-xing; Wang, Wei-dong

2018-04-01

Atomistic simulations are capable of providing insights into physical mechanisms responsible for mechanical properties of the transition metal of Tantalum (Ta). By using molecular dynamics (MD) method, temperature and pressure dependences of the elastic properties of Ta single crystals are investigated through tensile loading. First of all, a comparative study between two types of embedded-atom method (EAM) potentials is made in term of the elastic properties of Ta single crystals. The results show that Ravelo-EAM (Physical Review B, 2013, 88: 134101) potential behaves well at different hydrostatic pressures. Then, the MD simulation results based on the Ravelo-EAM potential show that Ta will experience a body-centered-cubic (BCC) to face-centered-cubic (FCC) phase transition before fracture under tensile loading at 1 K temperature, and model size and strain rate have no obvious effects on tensile behaviors of Ta. Next, from the simulation results at the system temperature from 1 to 1500 K, it can be derived that the elastic modulus of E 100 linearly decrease with the increasing temperature, while the yielding stress decrease with conforming a quadratic polynomial formula. Finally, the pressure dependence of the elastic properties is performed from 0 to 140 GPa and the observations show that the elastic modulus increases with the increasing pressure overall.

Universal relation for size dependent thermodynamic properties of metallic nanoparticles.

Science.gov (United States)

Xiong, Shiyun; Qi, Weihong; Cheng, Yajuan; Huang, Baiyun; Wang, Mingpu; Li, Yejun

2011-06-14

The previous model on surface free energy has been extended to calculate size dependent thermodynamic properties (i.e., melting temperature, melting enthalpy, melting entropy, evaporation temperature, Curie temperature, Debye temperature and specific heat capacity) of nanoparticles. According to the quantitative calculation of size effects on the calculated thermodynamic properties, it is found that most thermodynamic properties of nanoparticles vary linearly with 1/D as a first approximation. In other words, the size dependent thermodynamic properties P(n) have the form of P(n) = P(b)(1 -K/D), in which P(b) is the corresponding bulk value and K is the material constant. This may be regarded as a scaling law for most of the size dependent thermodynamic properties for different materials. The present predictions are consistent literature values. This journal is © the Owner Societies 2011

Physical properties of naked DNA influence nucleosome positioning and correlate with transcription start and termination sites in yeast

Directory of Open Access Journals (Sweden)

Soler-López Montserrat

2011-10-01

Full Text Available Abstract Background In eukaryotic organisms, DNA is packaged into chromatin structure, where most of DNA is wrapped into nucleosomes. DNA compaction and nucleosome positioning have clear functional implications, since they modulate the accessibility of genomic regions to regulatory proteins. Despite the intensive research effort focused in this area, the rules defining nucleosome positioning and the location of DNA regulatory regions still remain elusive. Results Naked (histone-free and nucleosomal DNA from yeast were digested by microccocal nuclease (MNase and sequenced genome-wide. MNase cutting preferences were determined for both naked and nucleosomal DNAs. Integration of their sequencing profiles with DNA conformational descriptors derived from atomistic molecular dynamic simulations enabled us to extract the physical properties of DNA on a genomic scale and to correlate them with chromatin structure and gene regulation. The local structure of DNA around regulatory regions was found to be unusually flexible and to display a unique pattern of nucleosome positioning. Ab initio physical descriptors derived from molecular dynamics were used to develop a computational method that accurately predicts nucleosome enriched and depleted regions. Conclusions Our experimental and computational analyses jointly demonstrate a clear correlation between sequence-dependent physical properties of naked DNA and regulatory signals in the chromatin structure. These results demonstrate that nucleosome positioning around TSS (Transcription Start Site and TTS (Transcription Termination Site (at least in yeast is strongly dependent on DNA physical properties, which can define a basal regulatory mechanism of gene expression.

Dependence of Glass Mechanical Properties on Thermal and Pressure History

DEFF Research Database (Denmark)

Smedskjær, Morten Mattrup; Bauchy, Mathieu

Predicting the properties of new glasses prior to manufacturing is a topic attracting great industrial and scientific interest. Mechanical properties are currently of particular interest given the increasing demand for stronger, thinner, and more flexible glasses in recent years. However, as a non......-equilibrium material, the structure and properties of glass depend not only on its composition, but also on its thermal and pressure histories. Here we review our recent findings regarding the thermal and pressure history dependence of indentation-derived mechanical properties of oxide glasses....

Study on the physical properties of the dynamic filter: unidimensional modulation

International Nuclear Information System (INIS)

Souza, Roberto Salomon de

2005-10-01

The present work shows an characterization of the Varian linear accelerator EDW physical properties, through experimental determinations, comparing them with calculations made by CadPlan treatment planning system, under the same conditions. The following parameters were determined: EDW factor for square and rectangular fields on the central axis and off-axis, EDW factor dependency with the static collimator, percentage depth dose, EDW factor dependency with the depth on the central axis and off-axis, EDW angles and field profiles on several depths. It was verified that the EDW factor diminishes with the field size increment and with EDW nominal angle increment, and increases with energy increment. It is independent of the X collimator and dynamic collimator, except for small field sizes. It doesn't vary with depth on the central axis, but varies on the off-axis distances. A difference between EDW nominal angles and the EDW obtained experimentally was found, but it doesn't interfere in the treatment results. At the end of this work, a set of physical parameters to be determined for the commissioning, clinical implementation and quality assurance of the EDW is suggested. (author)

Physical properties of sunflower seeds during drying

Directory of Open Access Journals (Sweden)

Thaís Adriana de Souza Smaniotto

2017-03-01

Full Text Available The aim of this work was to determine the effect that the moisture content has on the physical properties of sunflower seeds. The cultivar Olisun 3, with an initial moisture content of 34.1 (% wb, was used and then subjected to drying in an oven with forced air ventilation under three temperature conditions: 40, 60 and 80 °C. The reduction in the moisture content during drying was monitored by the gravimetric method until it reached a final moisture content of 8.0 ± 1.0 (% wb. The physical properties were analysed: the bulk density, true density, intergranular porosity and volumetric shrinkage of the mass and unit and terminal velocity. The reduction in the moisture content influenced the physical properties of sunflower seeds and caused a decrease in the intergranular porosity, bulk density and true density at all examined temperatures. The mass and volumetric contractions of the unit and reduction in shrinkage rates all increased with the drying of sunflower seeds at all studied temperatures. The terminal velocity increased as the moisture content of the grains increased, which was more evident at the drying temperature of 80 °C.

Physical properties and rock physics models of sediment containing natural and laboratory-formed methane gas hydrate

Science.gov (United States)

Winters, W.J.; Pecher, I.A.; Waite, W.F.; Mason, D.H.

2004-01-01

This paper presents results of shear strength and acoustic velocity (p-wave) measurements performed on: (1) samples containing natural gas hydrate from the Mallik 2L-38 well, Mackenzie Delta, Northwest Territories; (2) reconstituted Ottawa sand samples containing methane gas hydrate formed in the laboratory; and (3) ice-bearing sands. These measurements show that hydrate increases shear strength and p-wave velocity in natural and reconstituted samples. The proportion of this increase depends on (1) the amount and distribution of hydrate present, (2) differences, in sediment properties, and (3) differences in test conditions. Stress-strain curves from the Mallik samples suggest that natural gas hydrate does not cement sediment grains. However, stress-strain curves from the Ottawa sand (containing laboratory-formed gas hydrate) do imply cementation is present. Acoustically, rock physics modeling shows that gas hydrate does not cement grains of natural Mackenzie Delta sediment. Natural gas hydrates are best modeled as part of the sediment frame. This finding is in contrast with direct observations and results of Ottawa sand containing laboratory-formed hydrate, which was found to cement grains (Waite et al. 2004). It therefore appears that the microscopic distribution of gas hydrates in sediment, and hence the effect of gas hydrate on sediment physical properties, differs between natural deposits and laboratory-formed samples. This difference may possibly be caused by the location of water molecules that are available to form hydrate. Models that use laboratory-derived properties to predict behavior of natural gas hydrate must account for these differences.

Physical properties of self-curing concrete (SCUC

Directory of Open Access Journals (Sweden)

Magda I. Mousa

2015-08-01

The results show that the use of self-curing agent (Ch. in concrete effectively improves the physical properties compared with conventional concrete. On the other hand, up to 15% saturated leca was effective while 20% saturated leca was effective for permeability and mass loss but adversely affects the sorptivity and volumetric water absorption. Self-curing agent Ch. was more effective than self-curing agent leca. In all cases, both 2% Ch. and 15% leca were the optimum values. Higher cement content and/or lower water–cement ratio leads to more effective results of self-curing agents in concrete. Incorporation of silica fume into concrete mixtures enhances all physical properties.

Physical and Digital Security Mechanisms: Properties, Combinations and Trade-offs

NARCIS (Netherlands)

van Cleeff, A.

2015-01-01

The usage of information technology implies the replacement of physical systems with digital systems: we use information technology because some properties of software, such as high speed, low cost and high accuracy, are more desirable than the corresponding properties of physical systems.

A conceptual model of independence and dependence for adults with chronic physical illness and disability.

Science.gov (United States)

Gignac, M A; Cott, C

1998-09-01

This paper presents a conceptual model of physical independence and dependence as it relates to adult onset, chronic physical illness and disability. Physical independence and dependence are presented as two separate, continuous, and multiply determined constructs, and illustrations are provided of situations where people can be independent, dependent, not independent, or experience imposed dependence. The paper also discusses potential determinants of physical independence and dependence, including different domains of disability, the role of subjective perceptions, demographics, the physical and social/political environments, personal resources, attitudes and coping resources, illness and efficacy appraisals, and the nature of the assistive relationship. The paper extends work on physical independence and dependence by synthesizing the findings from previous studies and incorporating the findings from other relevant areas of research into the area. It also expands on the concepts of physical independence and dependence, as well as their determinants, and relates independence and dependence to other outcomes of interest such as service delivery.

Physical and structural properties of polyaniline/microcrystalline cellulose nanocomposite

Science.gov (United States)

Abdi, Mahnaz M.; Liyana, Rawaida; Tahir, Paridah Md; Heng, Lee Yook; Sulaiman, Yusran; Waheeda, Nur Farhana; Hassan, Nabihah Abu

2017-12-01

A composite of Polyaniline/Microcrystalline Cellulose (PAni/MCC) was prepared via a chemical polymerization method in the presence of ammonium persulfate (NH4)2S2O8 as oxidant and cetyltrimethylammonium bromide (CTAB) as a cationic surfactant. The results of FESEM showed that the morphology of nanocomposite depends on the monomer concentration. Wire-like and porous nanostructure was observed for PAni/MCC/CTAB composite that could be suitable for enzyme immobilization and sensor applications. The electrochemical properties of the composites were studied using Cyclic Voltammetry (CV) and it was shown that PAni/MCC/CTAB composite generated a higher current response compared to the pure PAni. The synergy effect of MCC and CTAB on the physical and electrochemical properties of composite resulted in higher electron transferring in PAni/MCC/CTAB. The presence of significant peaks of PAni and MCC in FT-IR spectrum of nanocomposite indicating polymerization of aniline on the surface of MCC. Characteristic peaks of crystalline cellulose were observed at 22.8 and 14.7 2theta in XRD pattern.

Sensitivity analyses of biodiesel thermo-physical properties under diesel engine conditions

DEFF Research Database (Denmark)

Cheng, Xinwei; Ng, Hoon Kiat; Gan, Suyin

2016-01-01

This reported work investigates the sensitivities of spray and soot developments to the change of thermo-physical properties for coconut and soybean methyl esters, using two-dimensional computational fluid dynamics fuel spray modelling. The choice of test fuels made was due to their contrasting...... saturation-unsaturation compositions. The sensitivity analyses for non-reacting and reacting sprays were carried out against a total of 12 thermo-physical properties, at an ambient temperature of 900 K and density of 22.8 kg/m3. For the sensitivity analyses, all the thermo-physical properties were set...... as the baseline case and each property was individually replaced by that of diesel. The significance of individual thermo-physical property was determined based on the deviations found in predictions such as liquid penetration, ignition delay period and peak soot concentration when compared to those of baseline...

Size-dependent mechanical properties of 2D random nanofibre networks

International Nuclear Information System (INIS)

Lu, Zixing; Zhu, Man; Liu, Qiang

2014-01-01

The mechanical properties of nanofibre networks (NFNs) are size dependent with respect to different fibre diameters. In this paper, a continuum model is developed to reveal the size-dependent mechanical properties of 2D random NFNs. Since such size-dependent behaviours are attributed to different micromechanical mechanisms, the surface effects and the strain gradient (SG) effects are, respectively, introduced into the mechanical analysis of NFNs. Meanwhile, a modified fibre network model is proposed, in which the axial, bending and shearing deformations are incorporated. The closed-form expressions of effective modulus and Poisson's ratio are obtained for NFNs. Different from the results predicted by conventional fibre network model, the present model predicts the size-dependent mechanical properties of NFNs. It is found that both surface effects and SG effects have significant influences on the effective mechanical properties. Moreover, the present results show that the shearing deformation of fibre segment is also crucial to precisely evaluate the effective mechanical properties of NFNs. This work mainly aims to provide an insight into the micromechanical mechanisms of NFNs. Besides, this work is also expected to provide a more accurate theoretical model for 2D fibre networks. (paper)

Physical Properties of Granulates Used in Analogue Experiments of Caprock Failure and Sediment Remobilisation

Science.gov (United States)

Kukowski, N.; Warsitzka, M.; May, F.

2014-12-01

Geological systems consisting of a porous reservoir and a low-permeable caprock are prone to hydraulic fracturing, if pore pressure rises to the effective stress. Under certain conditions, hydraulic fracturing is associated with sediment remobilisation, e.g. sand injections or pipes, leading to reduced seal capacity of the caprock. In dynamically scaled analogue experiments using granular materials and air pressure, we intent to investigate strain patterns and deformation mechanisms during caprock failure and fluidisation of shallow over-pressured reservoirs. The aim of this study is to improve the understanding of leakage potential of a sealing formation and the fluidisation potential of a reservoir formation depending on rock properties and effective stress. For reliable interpretation of analogue experiments, physical properties of analogue materials, e.g. frictional strength, cohesion, density, permeability etc., have to be correctly scaled according to those of their natural equivalents. The simulation of caprock requires that the analogue material possess a low permeability and is capable to shear failure and tensional failure. In contrast, materials representing the reservoir have to possess high porosity and low shear strength. In order to find suitable analogue materials, we measured the stress-strain behaviour and the permeability of over 25 different types of natural and artificial granular materials, e.g. glass powder, siliceous microspheres, diatomite powder, loess, or plastic granulate. Here, we present data of frictional parameters, compressibility and permeability of these granular materials characterized as a function of sphericity, grain size, and density. The repertoire of different types of granulates facilitates the adjustment of accurate mechanical properties in the analogue experiments. Furthermore, conditions during seal failure and fluidisation can be examined depending on the wide range of varying physical properties.

Swelling and mechanical properties of physically crosslinked poly(vinyl alcohol) hydrogels.

Science.gov (United States)

Suzuki, Atsushi; Sasaki, Saori

2015-12-01

Physically crosslinked poly(vinyl alcohol) gels are versatile biomaterials due to their excellent biocompatibility. In the past decades, physically crosslinked poly(vinyl alcohol) and poly(vinyl alcohol)-based hydrogels have been extensively studied for biomedical applications. However, these materials have not yet been implemented due to their mechanical strength. Physically crosslinked poly(vinyl alcohol) gels consist of a swollen amorphous network of poly(vinyl alcohol) physically crosslinked by microcrystallites. Although the mechanical properties can be improved to some extent by controlling the distribution of microcrystallites on the nano- and micro-scales, enhancing the mechanical properties while maintaining high water content remains very difficult. It may be technologically impossible to significantly improve the mechanical properties while keeping the gel's high water absorbance ability using conventional fabrication methods. Physical and chemical understandings of the swelling and mechanical properties of physically crosslinked poly(vinyl alcohol) gels are considered here; some promising strategies for their practical applications are presented. This review focuses more on the recent studies on swelling and mechanical properties of poly(vinyl alcohol) hydrogels, prepared using only poly(vinyl alcohol) and pure water with no other chemicals, as potential biomedical materials. © IMechE 2015.

Structural Characteristics and Physical Properties of Tectonically Deformed Coals

OpenAIRE

Yiwen Ju; Zhifeng Yan; Xiaoshi Li; Quanlin Hou; Wenjing Zhang; Lizhi Fang; Liye Yu; Mingming Wei

2012-01-01

Different mechanisms of deformation could make different influence on inner structure and physical properties of tectonically deformed coal (TDC) reservoirs. This paper discusses the relationship between macromolecular structure and physical properties of the Huaibei-Huainan coal mine areas in southern North China. The macromolecular structure and pore characteristics are systematically investigated by using techniques such as X-ray diffraction (XRD), high-resolution transmission electron mic...

Physical Properties of Hanford Transuranic Waste

Energy Technology Data Exchange (ETDEWEB)

Berg, John C.

2010-03-25

The research described herein was undertaken to provide needed physical property descriptions of the Hanford transuranic tank sludges under conditions that might exist during retrieval, treatment, packaging and transportation for disposal. The work addressed the development of a fundamental understanding of the types of systems represented by these sludge suspensions through correlation of the macroscopic rheological properties with particle interactions occurring at the colloidal scale in the various liquid media. The results of the work have advanced existing understanding of the sedimentation and aggregation properties of complex colloidal suspensions. Bench scale models were investigated with respect to their structural, colloidal and rheological properties that should be useful for the development and optimization of techniques to process the wastes at various DOE sites.

Effect of ozone gas processing on physical and chemical properties ...

African Journals Online (AJOL)

Purpose: To investigate the effects of ozone treatment on chemical and physical properties of wheat (Triticum aestivum L.) gluten, glutenin and gliadin. Methods: Wheat proteins isolated from wheat flour were treated with ozone gas. The physical and chemical properties of gluten proteins were investigated after treatment ...

Investigation of physical properties and surface morphology of Cu nanolayer deposited on glass and (Al, Fe) thin films by DC magnetron sputtering

Energy Technology Data Exchange (ETDEWEB)

Eslami, P.A. [Islamic Azad Univ., North Tehran (Iran, Islamic Republic of). Dept. of Chemistry; Islamic Azad Univ., Tabriz (Iran, Islamic Republic of). Dept. of Science-Applied Chemistry; Laheghi, S.N.; Ghoranneviss, M. [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Plasma Research Center; Moradi, S. [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Dept. of Chemistry; Aberumand, P. [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Science and Research Laboratory Complex

2008-07-01

The applications for copper (Cu) thin films with micro or nanostructural dimensions range from catalysis to microelectronic devices. This paper reported on a study in which DC magnetron sputtering was used to coat iron (Fe), copper (Cu) and aluminum (Al) on glass substrate under a particular voltage, time and optimized deposition pressure. The samples were then coated with Cu using the same technique in preparation of different multilayers. Physical properties such as transmission and reflection per cent, magnetic and electrical properties, size and surface morphology were analyzed using data from AFM, XRD, SEM, Four point probe, and magneto resistive spectrophotometers. The study showed that the size, surface morphology and some physical properties of Cu nanolayer depend on substrate materials, surface morphology and physical properties below the nanolayer. Future work will focus on chemical properties such as catalytic and electrochemical properties. Copper nanoparticles will also be synthesized on other materials such as ZnO. 14 refs., 1 tab., 3 figs.

Recalled first reactions to inhaling nicotine predict the level of physical dependence.

Science.gov (United States)

Wellman, Robert J; DiFranza, Joseph R; O'Loughlin, Jennifer

2014-10-01

The level of physical dependence is a measure of addiction that correlates highly with addiction-associated changes in brain structure. We sought to determine whether age at first inhalation and initial reactions to inhaling nicotine are related to level of physical dependence in early adulthood. Young adults (n=312; mean age=24 years; 51% female) from the Nicotine Dependence in Teens study who had smoked at least once in the preceding three months completed self-report questionnaires in 2011-12. We assessed level of physical dependence with three validated self-report items assessing 'wanting,' 'craving' and 'needing' triggered by nicotine deprivation. Survey items assessed smoking behavior, including age at first inhalation, and recalled first reactions to inhaling nicotine. After adjusting for covariates, experiencing relaxation, heart racing/pounding, rush or "buzz" (OR=1.45; 95% CI: 1.08, 1.94) and dizziness (OR=1.58; 95% CI: 1.15, 2.18) at first nicotine inhalation were associated with an increased odds of being at a higher level of physical dependence in young adulthood; the association for experiencing relaxation (OR=1.78; 95% CI: 1.20, 2.64) and heart racing/pounding (OR=1.51; 95% CI: 1.00, 2.28) persisted after additionally controlling for all other first reactions. Neither age at first inhalation nor unpleasant first reactions predicted level of physical dependence. In accordance with prior research, our findings suggest that smokers who are particularly sensitive to the pleasant, "buzz-related" and generally arousing effects of nicotine may be more likely to attain higher levels of physical dependence. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Analysis of microwave heating of materials with temperature-dependent properties

International Nuclear Information System (INIS)

Ayappa, K.G.; Davis, H.T.; Davis, E.A.; Gordon, J.

1991-01-01

In this paper transient temperature profiles in multilayer slabs are predicted, by simultaneously solving Maxwell's equations with the heat conduction equation, using Galerkin-finite elements. It is assumed that the medium is homogeneous and has temperature-dependent dielectric and thermal properties. The method is illustrated with applications involving the heating of food and polymers with microwaves. The temperature dependence of dielectric properties affects the heating appreciably, as is shown by comparison with a constant property model

The physical properties of peat: a key factor for modern growing media

Directory of Open Access Journals (Sweden)

J-C. Michel

2010-04-01

Full Text Available This article identifies criteria for assessing the physical properties (water retention characteristics, wettability and physical stability of growing media which influence the availability of air and water to plant roots. The various materials that are currently in use are assessed for these properties. The analysis of physical properties indicates that weakly decomposed (H1–H5, generally referred to as white Sphagnum peat is still indispensable for soil-less horticulture. Whilst a number of materials can be used as peat additives, especially to improve aeration, no alternative products with equivalent physical properties are available at present.

The physical properties and evolution of Lyα emitting galaxies

Science.gov (United States)

Pentericci, L.; Grazian, A.; Fontana, A.

2009-05-01

A significant fraction of high redshift starburst galaxies presents strong Lyα emission. Understanding the nature of these galaxies is important to assess the role they played in the early Universe and to shed light on the relation between the narrow band selected Lyα emitters and the Lyman break galaxies: are the Lyα emitters a subset of the general LBG population? or do they represent the youngest galaxies in their early phases of formation? We studied a sample of UV continuum selected galaxies from z~2.5 to z~6 (U, B, V and i-dropouts) from the GOODS-South survey, that have been observed spectroscopically. Using the GOODS-MUSIC catalog we investigated their physical properties, such as total masses, ages, SFRs, extinction etc as determined from a spectrophotometric fit to the multi-wavelength (U band to mid-IR) SEDs, and their dependence on the emission line characteristics. In particular we determined the nature of the LBGs with Lyα in emission and compared them to the properties of narrow band selected Lyα emitters. For U and B-dropouts we also compared the properties of LBGs with and without the Lyα emission line.

Physical Properties of Niobium and Specifications for Fabrication of Superconducting Cavities

International Nuclear Information System (INIS)

Antoine, C.; Foley, M.; Dhanaraj, N.

2011-01-01

It is important to distinguish among the properties of niobium, the ones that are related to the cavity's SRF performances, the formability of the material, and the mechanical behavior of the formed cavity. In general, the properties that dictate each of the above mentioned characteristics have a detrimental effect on one another and in order to preserve the superconducting properties without subduing the mechanical behavior, a balance has to be established. Depending on the applications, some parameters become less important and an understanding of the physical origin of the requirements might help in this optimization. SRF applications require high purity niobium (high RRR), but pure niobium is very soft from fabrication viewpoint. Moreover conventional fabrication techniques tend to override the effects of any metallurgical process meant to strengthen it. As those treatments dramatically affect the forming of the material they should be avoided. These unfavorable mechanical properties have to be accounted for in the design of the cavities rather than in the material specification. The aim of this paper is to review the significance of the important mechanical properties used to characterize niobium and to present the optimal range of values. Most of the following information deals with the specification of sheets for cell forming unless otherwise noted.

Physical Properties of Niobium and Specifications for Fabrication of Superconducting Cavities

Energy Technology Data Exchange (ETDEWEB)

Antoine, C.; Foley, M.; Dhanaraj, N.; /Fermilab

2011-07-01

It is important to distinguish among the properties of niobium, the ones that are related to the cavity's SRF performances, the formability of the material, and the mechanical behavior of the formed cavity. In general, the properties that dictate each of the above mentioned characteristics have a detrimental effect on one another and in order to preserve the superconducting properties without subduing the mechanical behavior, a balance has to be established. Depending on the applications, some parameters become less important and an understanding of the physical origin of the requirements might help in this optimization. SRF applications require high purity niobium (high RRR), but pure niobium is very soft from fabrication viewpoint. Moreover conventional fabrication techniques tend to override the effects of any metallurgical process meant to strengthen it. As those treatments dramatically affect the forming of the material they should be avoided. These unfavorable mechanical properties have to be accounted for in the design of the cavities rather than in the material specification. The aim of this paper is to review the significance of the important mechanical properties used to characterize niobium and to present the optimal range of values. Most of the following information deals with the specification of sheets for cell forming unless otherwise noted.

PhySIC: a veto supertree method with desirable properties.

Science.gov (United States)

Ranwez, Vincent; Berry, Vincent; Criscuolo, Alexis; Fabre, Pierre-Henri; Guillemot, Sylvain; Scornavacca, Celine; Douzery, Emmanuel J P

2007-10-01

This paper focuses on veto supertree methods; i.e., methods that aim at producing a conservative synthesis of the relationships agreed upon by all source trees. We propose desirable properties that a supertree should satisfy in this framework, namely the non-contradiction property (PC) and the induction property (PI). The former requires that the supertree does not contain relationships that contradict one or a combination of the source topologies, whereas the latter requires that all topological information contained in the supertree is present in a source tree or collectively induced by several source trees. We provide simple examples to illustrate their relevance and that allow a comparison with previously advocated properties. We show that these properties can be checked in polynomial time for any given rooted supertree. Moreover, we introduce the PhySIC method (PHYlogenetic Signal with Induction and non-Contradiction). For k input trees spanning a set of n taxa, this method produces a supertree that satisfies the above-mentioned properties in O(kn(3) + n(4)) computing time. The polytomies of the produced supertree are also tagged by labels indicating areas of conflict as well as those with insufficient overlap. As a whole, PhySIC enables the user to quickly summarize consensual information of a set of trees and localize groups of taxa for which the data require consolidation. Lastly, we illustrate the behaviour of PhySIC on primate data sets of various sizes, and propose a supertree covering 95% of all primate extant genera. The PhySIC algorithm is available at http://atgc.lirmm.fr/cgi-bin/PhySIC.

Impacts of land leveling on lowland soil physical properties

Directory of Open Access Journals (Sweden)

José Maria Barbat Parfitt

2014-02-01

Full Text Available The practice of land leveling alters the soil surface to create a uniform slope to improve land conditions for the application of all agricultural practices. The aims of this study were to evaluate the impacts of land leveling through the magnitudes, variances and spatial distributions of selected soil physical properties of a lowland area in the State of Rio Grande do Sul, Brazil; the relationships between the magnitude of cuts and/or fills and soil physical properties after the leveling process; and evaluation of the effect of leveling on the spatial distribution of the top of the B horizon in relation to the soil surface. In the 0-0.20 m layer, a 100-point geo-referenced grid covering two taxonomic soil classes was used in assessment of the following soil properties: soil particle density (Pd and bulk density (Bd; total porosity (Tp, macroporosity (Macro and microporosity (Micro; available water capacity (AWC; sand, silt, clay, and dispersed clay in water (Disp clay contents; electrical conductivity (EC; and weighted average diameter of aggregates (WAD. Soil depth to the top of the B horizon was also measured before leveling. The overall effect of leveling on selected soil physical properties was evaluated by paired "t" tests. The effect on the variability of each property was evaluated through the homogeneity of variance test. The thematic maps constructed by kriging or by the inverse of the square of the distances were visually analyzed to evaluate the effect of leveling on the spatial distribution of the properties and of the top of the B horizon in relation to the soil surface. Linear regression models were fitted with the aim of evaluating the relationship between soil properties and the magnitude of cuts and fills. Leveling altered the mean value of several soil properties and the agronomic effect was negative. The mean values of Bd and Disp clay increased and Tp, Macro and Micro, WAD, AWC and EC decreased. Spatial distributions of all

Perceptions of Family Dependence by the Physically Disabled

Science.gov (United States)

Thomas, Kenneth R.; Britton, Jean O.

1973-01-01

The ralationship between six demographic characteristics and perceptions of family dependence were investigated for 170 physically disabled adults using Osgood's semantic differential technique. Implications of these findings for rehabilitation practice and further research are presented. (Author)

Shape-dependent electronic properties of blue phosphorene nano-flakes

Energy Technology Data Exchange (ETDEWEB)

Bhatia, Pradeep; Swaroop, Ram; Kumar, Ashok, E-mail: ashok@cup.ac.in [Center for Physical Sciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda-151001 (India)

2016-05-06

In recent year’s considerable attention has been given to the first principles method for modifying and controlling electronic properties of nano-materials. We performed DFT-based calculations on the electronic properties of zigzag-edged nano-flakes of blue phosphorene with three possible shapes namely rectangular, triangular and hexagonal. We observed that HOMO-LUMO gap of zigzag phosphorene nano-flakes with different shapes is ∼2.9 eV with H-passivations and ∼0.7 – 1.2 eV in pristine cases. Electronic properties of blue phosphorene nano-flakes show the strong dependence on their shape. We observed that distributions of molecular orbitals were strongly affected by the different shapes. Zigzag edged considered nanostructures are non-magnetic and semiconducting in nature. The shape dependent electronic properties may find applications in tunable nano-electronics.

Materials used to simulate physical properties of human skin.

Science.gov (United States)

Dąbrowska, A K; Rotaru, G-M; Derler, S; Spano, F; Camenzind, M; Annaheim, S; Stämpfli, R; Schmid, M; Rossi, R M

2016-02-01

For many applications in research, material development and testing, physical skin models are preferable to the use of human skin, because more reliable and reproducible results can be obtained. This article gives an overview of materials applied to model physical properties of human skin to encourage multidisciplinary approaches for more realistic testing and improved understanding of skin-material interactions. The literature databases Web of Science, PubMed and Google Scholar were searched using the terms 'skin model', 'skin phantom', 'skin equivalent', 'synthetic skin', 'skin substitute', 'artificial skin', 'skin replica', and 'skin model substrate.' Articles addressing material developments or measurements that include the replication of skin properties or behaviour were analysed. It was found that the most common materials used to simulate skin are liquid suspensions, gelatinous substances, elastomers, epoxy resins, metals and textiles. Nano- and micro-fillers can be incorporated in the skin models to tune their physical properties. While numerous physical skin models have been reported, most developments are research field-specific and based on trial-and-error methods. As the complexity of advanced measurement techniques increases, new interdisciplinary approaches are needed in future to achieve refined models which realistically simulate multiple properties of human skin. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Preparation and temperature dependence of electrostriction properties for PMN-based composite ceramics

International Nuclear Information System (INIS)

Zhao Jingbo; Qu Shaobo; Du Hongliang; Zheng Yanju; Xu Zhuo

2009-01-01

Both low- and high-temperature units were prepared by columbite precursor method, and Pb(Mg 1/3 Nb 2/3 )O 3 (PMN)-based ferroelectric composite ceramics were prepared by conventional method, baking-block method and coating method, respectively. The effects of preparation methods on dielectric and electrostriction properties as well as the temperature-dependence property of the obtained composite ceramics were studied. The results show that compared with the samples prepared by traditional blend sintering method, of the samples prepared by baking-block and coating methods have much better dielectric and electrostriction properties. For those prepared by baking-block method, the electrostriction temperature-dependence properties are good in the range of 20-60 deg. C. For those prepared by coating method, the dielectric temperature-dependence properties are also good in the broad range of -30 to 70 deg. C, and the electrostriction temperature properties are better than those prepared by blending-block. Compared with the traditional blending sintering method, the dielectric and electrostriction temperature-dependence properties are much better, which effectively solves the problem of temperature properties existing in present engineering applications.

Isospin dependent properties of asymmetric nuclear matter

Science.gov (United States)

Chowdhury, P. Roy; Basu, D. N.; Samanta, C.

2009-07-01

The density dependence of nuclear symmetry energy is determined from a systematic study of the isospin dependent bulk properties of asymmetric nuclear matter using the isoscalar and isovector components of the density dependent M3Y interaction. The incompressibility K∞ for the symmetric nuclear matter, the isospin dependent part Kasy of the isobaric incompressibility, and the slope L are all in excellent agreement with the constraints recently extracted from measured isotopic dependence of the giant monopole resonances in even-A Sn isotopes, from the neutron skin thickness of nuclei, and from analyses of experimental data on isospin diffusion and isotopic scaling in intermediate energy heavy-ion collisions. This work provides a fundamental basis for the understanding of nuclear matter under extreme conditions and validates the important empirical constraints obtained from recent experimental data.

Effects of physical properties on thermo-fluids cavitating flows

Science.gov (United States)

Chen, T. R.; Wang, G. Y.; Huang, B.; Li, D. Q.; Ma, X. J.; Li, X. L.

2015-12-01

The aims of this paper are to study the thermo-fluid cavitating flows and to evaluate the effects of physical properties on cavitation behaviours. The Favre-averaged Navier-Stokes equations with the energy equation are applied to numerically investigate the liquid nitrogen cavitating flows around a NASA hydrofoil. Meanwhile, the thermodynamic parameter Σ is used to assess the thermodynamic effects on cavitating flows. The results indicate that the thermodynamic effects on the thermo-fluid cavitating flows significantly affect the cavitation behaviours, including pressure and temperature distribution, the variation of physical properties, and cavity structures. The thermodynamic effects can be evaluated by physical properties under the same free-stream conditions. The global sensitivity analysis of liquid nitrogen suggests that ρv, Cl and L significantly influence temperature drop and cavity structure in the existing numerical framework, while pv plays the dominant role when these properties vary with temperature. The liquid viscosity μl slightly affects the flow structure via changing the Reynolds number Re equivalently, however, it hardly affects the temperature distribution.

Spontaneous appetence for wheel-running: a model of dependency on physical activity in rat.

Science.gov (United States)

Ferreira, Anthony; Lamarque, Stéphanie; Boyer, Patrice; Perez-Diaz, Fernando; Jouvent, Roland; Cohen-Salmon, Charles

2006-12-01

According to human observations of a syndrome of physical activity dependence and its consequences, we tried to examine if running activity in a free activity paradigm, where rats had a free access to activity wheel, may present a valuable animal model for physical activity dependence and most generally to behavioral dependence. The pertinence of reactivity to novelty, a well-known pharmacological dependence predictor was also tested. Given the close linkage observed in human between physical activity and drugs use and abuse, the influence of free activity in activity wheels on reactivity to amphetamine injection and reactivity to novelty were also assessed. It appeared that (1) free access to wheel may be used as a valuable model for physical activity addiction, (2) two populations differing in activity amount also differed in dependence to wheel-running. (3) Reactivity to novelty did not appeared as a predictive factor for physical activity dependence (4) activity modified novelty reactivity and (5) subjects who exhibited a high appetence to wheel-running, presented a strong reactivity to amphetamine. These results propose a model of dependency on physical activity without any pharmacological intervention, and demonstrate the existence of individual differences in the development of this addiction. In addition, these data highlight the development of a likely vulnerability to pharmacological addiction after intense and sustained physical activity, as also described in man. This model could therefore prove pertinent for studying behavioral dependencies and the underlying neurobiological mechanisms. These results may influence the way psychiatrists view behavioral dependencies and phenomena such as doping in sport or addiction to sport itself.

Comparative studies of physical properties of kinesiotapes.

Science.gov (United States)

Gołąb, Agnieszka; Kulesa-Mrowiecka, Małgorzata; Gołąb, Marek

2017-01-01

Nowadays we observe growing popularity of kinesiotaping as a supportive method in physiotherapy. In documents available on kinesiotaping we can find that mechanical properties of tapes are similar to the ones of a human skin, but usually there is hardly any numerical data characterizing these properties. Therefore, testing and comparing physical properties of commercially available kinesiotapes seems to be important. Physical properties of five commercially available kinesiotapes were examined. Strain vs. stress data was collected up to 15 N. Program Origin 9.0 was used for data analysis. The obtained results show that up to about 2 N the strain vs. stress characteristics of the tested tapes are similar while for greater stress they differ essentially. An alternative, to commonly used, way of defining relative strain is proposed. This definition could be more suitable in those cases when desired tape tensions are higher than 50% i.e. in ligament and tendon techniques.

Effect of decompression drying treatment on physical properties of solid foods.

Science.gov (United States)

Morikawa, Takuya; Takada, Norihisa; Miura, Makoto

2017-04-01

This study used a decompression drying instrument to investigate the effects of a drying treatment on the physical properties of solid foods. Commercial tofu was used as a model food and was treated at different temperature and pressure conditions in a drying chamber. Overall, high temperatures resulted in better drying. Additionally, pressure in the chamber influenced the drying conditions of samples. Differences in physical properties, such as food texture, shrinkage, and color were observed among some samples, even with similar moisture content. This was caused by differences in moisture distribution in the food, which seems to have manifested as a thin, dried film on the surfaces of samples. It caused inefficient drying and changes in physical properties. Control of the drying conditions (i.e. pressure and heat supply) has relations with not only physical properties, but also the drying efficiency of solid foods.

Detailed physical properties prediction of pure methyl esters for biodiesel combustion modeling

International Nuclear Information System (INIS)

An, H.; Yang, W.M.; Maghbouli, A.; Chou, S.K.; Chua, K.J.

2013-01-01

Highlights: ► Group contribution methods from molecular level have been used for the prediction. ► Complete prediction of the physical properties for 5 methyl esters has been done. ► The predicted results can be very useful for biodiesel combustion modeling. ► Various models have been compared and the best model has been identified. ► Predicted properties are over large temperature ranges with excellent accuracies. -- Abstract: In order to accurately simulate the fuel spray, atomization, combustion and emission formation processes of a diesel engine fueled with biodiesel, adequate knowledge of biodiesel’s physical properties is desired. The objective of this work is to do a detailed physical properties prediction for the five major methyl esters of biodiesel for combustion modeling. The physical properties considered in this study are: normal boiling point, critical properties, vapor pressure, and latent heat of vaporization, liquid density, liquid viscosity, liquid thermal conductivity, gas diffusion coefficients and surface tension. For each physical property, the best prediction model has been identified, and very good agreements have been obtained between the predicted results and the published data where available. The calculated results can be used as key references for biodiesel combustion modeling.

Comparative Study of the Physical, Topographical and Biological Properties of Electrospinning PCL, PLLA, their Blend and Copolymer Scaffolds

Science.gov (United States)

Bolbasov, E.; Goreninskii, S.; Tverdokhlebov, S.; Mishanin, A.; Viknianshchuk, A.; Bezuidenhout, D.; Golovkin, A.

2018-05-01

Biodegradable polymers (blends, copolymers) could be the ideal materials for manufacturing of scaffolds for small diameter vascular graft. Such material characteristics as mechanical properties, chemical structure, nano- and micro topography, surface charge, porosity, wettability etc. are becoming the most important aspects for effectiveness of prosthesis biofunctionalization because of their great impact on cell adhesion, spreading, cell proliferation, differentiation and cell function. The aim of the study is to compare physical, topographical and biological properties of polycaprolactone (PCL), poly-L-lactic acid (PLLA), polycaprolactone + poly-L-lactic acid blend (PCL PLLA), L-lactide/Caprolactone copolymer (PLC7015) scaffolds fabricated with the same fiber thickness using electrospun technology. PCL PLLA scaffolds had the highest average pore area (pactive phase of adhesion process. We propose that physical and topographical properties of PCL, PLLA, their blend and copolymer are of a great dependence of chemical structure but could be changed during the manufacturing process that will lead to changes in biological properties.

Physical Properties of Intermetallic FE2VA1

Energy Technology Data Exchange (ETDEWEB)

Feng, Ye [Iowa State Univ., Ames, IA (United States)

2001-01-01

Fe₂VAl has recently been discovered to have a negative temperature coefficient of resistivity, moderately enhanced specific heat coefficient, and a large DOS at the Fermi level by photoemission. This triggered a round of heated research to understand the ground state of this material, both theoretically and experimentally. here they report a comprehensive characterization of Fe₂VAl. X-ray diffraction exhibited appreciable antisite disorder in all of our samples. FTIR spectroscopy measurements showed that the carrier density and scattering time had little sample-to-sample variation or temperature dependence for near-stoichiometric samples. FTIR and DC resistivity suggest that the transport properties of Fe₂VAl are influenced by both localized and delocalized carriers, with the former primarily responsible for the negative temperature coefficient of resistivity. Magnetization measurements reveal that near-stoichiometric samples have superparamagnetic clusters with at least two sizes of moments. X-ray photoemission from Fe core level showed localized magnetic moments on site-exchanged Fe. They conclude that in Fe₂VAl, antisite disorder causes significant modification to the semi-metallic band structure proposed by LDA calculations. With antisite disorder considered, they are now able to explain most of the physical properties of Fe₂VAl.

Physical Properties of Intermetallic FE2VA1

International Nuclear Information System (INIS)

Ye Feng

2002-01-01

Fe 2 VAl has recently been discovered to have a negative temperature coefficient of resistivity, moderately enhanced specific heat coefficient, and a large DOS at the Fermi level by photoemission. This triggered a round of heated research to understand the ground state of this material, both theoretically and experimentally. here they report a comprehensive characterization of Fe 2 VAl. X-ray diffraction exhibited appreciable antisite disorder in all of our samples. FTIR spectroscopy measurements showed that the carrier density and scattering time had little sample-to-sample variation or temperature dependence for near-stoichiometric samples. FTIR and DC resistivity suggest that the transport properties of Fe 2 VAl are influenced by both localized and delocalized carriers, with the former primarily responsible for the negative temperature coefficient of resistivity. Magnetization measurements reveal that near-stoichiometric samples have superparamagnetic clusters with at least two sizes of moments. X-ray photoemission from Fe core level showed localized magnetic moments on site-exchanged Fe. They conclude that in Fe 2 VAl, antisite disorder causes significant modification to the semi-metallic band structure proposed by LDA calculations. With antisite disorder considered, they are now able to explain most of the physical properties of Fe 2 VAl

Effect of at-home bleaching with different thickeners and aging on physical properties of a nanocomposite.

Science.gov (United States)

Gouveia, Thayla Hellen Nunes; Públio, Juliana do Carmo; Ambrosano, Glaucia Maria Bovi; Paulillo, Luís Alexandre Maffei Sartini; Aguiar, Flávio Henrique Baggio; Lima, Débora Alves Nunes Leite

2016-01-01

To evaluate the influence of 16% carbamide peroxide (CP) containing different thickeners on the physical characteristics of a nanocomposite resin submitted or not to accelerated artificial aging (AAA). One hundred samples were randomly distributed into two groups (n = 50) according to AAA. Each group was divided into 5 subgroups (n = 10) depending on the bleaching/thickener treatment: CP + carbopol, CP + natrosol, carbopol, natrosol, and no treatment (control). The physical properties tested were color (ΔE), gloss (GU), mean roughness (Ra), and Knoop microhardness (KHN). The resin surface was performed with atomic force microscopy (AFM). The color (variable Δ E) was assessed with two-way analysis of variance (ANOVA) and additionally with Tukey's and Dunnett's tests, the roughness values were submitted to Kruskal-Wallis, Dunn's, and Mann-Whitney's tests. Data on gloss and KHN were submitted to two-way ANOVA and Tukey's test (α = 0.05). Among the physical properties evaluated, CP + carbopol promoted a reduction in composite microhardness only, thus differing statistically from the controls. As for CP + natrosol, such a change was not observed. The aging process reduced all the physical properties, thus differing statistically from the nonaging group. CP + carbopol increased the roughness and decreased the gloss of aged resins, whereas natrosol reduced gloss only, which differed statistically from the controls. AFM showed evidence of the loss of organic matrix and exposure to load particles in the aged samples. Therefore, the replacement of carbopol with natrosol provided maintenance of the composite microhardness following bleaching. The aging process reduced the physical properties evaluated, and some changes were enhanced by the application of bleaching.

The dependence of stellar properties on initial cloud density

Science.gov (United States)

Jones, Michael O.; Bate, Matthew R.

2018-05-01

We investigate the dependence of stellar properties on the initial mean density of the molecular cloud in which stellar clusters form using radiation hydrodynamical simulations that resolve the opacity limit for fragmentation. We have simulated the formation of three star clusters from the gravitational collapse of molecular clouds whose densities vary by a factor of a hundred. As with previous calculations including radiative feedback, we find that the dependence of the characteristic stellar mass, Mc, on the initial mean density of the cloud, ρ, is weaker than the dependence of the thermal Jeans mass. However, unlike previous calculations, which found no statistically significant variation in the median mass with density, we find a weak dependence approximately of the form Mc∝ρ-1/5. The distributions of properties of multiple systems do not vary significantly between the calculations. We compare our results to the result of observational surveys of star-forming regions, and suggest that the similarities between the properties of our lowest density calculation and the nearby Taurus-Auriga region indicate that the apparent excess of solar-type stars observed may be due to the region's low density.

Nuclear materials thermo-physical property database and property analysis using the database

International Nuclear Information System (INIS)

Jeong, Yeong Seok

2002-02-01

It is necessary that thermo-physical properties and understand of nuclear materials for evaluation and analysis to steady and accident states of commercial and research reactor. In this study, development of nuclear materials thermo-properties database and home page. In application of this database, it is analyzed of thermal conductivity, heat capacity, enthalpy, and linear thermal expansion of fuel and cladding material and compared thermo-properties model in nuclear fuel performance evaluation codes with experimental data in database. Results of compare thermo-property model of UO 2 fuel and cladding major performance evaluation code, both are similar

Alteration dependent physical-mechanical properties of quartz-diorite building stones

Directory of Open Access Journals (Sweden)

Masoud Torkan

2016-12-01

Full Text Available The microscopic and geomechanical properties of igneous building stones include the level of alteration, presence of micro cracks, peak strength, porosity, proportion of detrimental minerals, etc. Porosity is reportedly of a devastating impact on the peak strength of igneous rocks. The quartz diorite rock samples in this study were selected from five quarries in Natanz, Iran and subject to microscopic and geomechanical investigations. The level of alteration and the minerals detrimental to the strength of the samples were identified from thin sections. Therefore, the geomechanical tests upon density, porosity, durability index, the Brazilian, and triaxial tests were conducted as per ISRM standards. The findings from microscopic studies reveal that alteration is of more intense impact on rock peak strength compared to that of porosity. The results were compared to standard values and a qualitative correlation between strength and microscopic properties was detected accentuating the importance of microscopic studies on construction stones. The correlation thereupon may be adopted in the exploration, exploitation, and process of construction stones to avoid heavy expenditures and damage to the environment.

Methyl Parathion Masks Withdrawal from Physical Dependence on Morphine

OpenAIRE

Zhu, Hong; Ho, Ing K.; Kramer, Robert E.; Baker, Rodney C.; Rockhold, Robin W.

2002-01-01

Abstract: The cholinergic system has been proposed to participate in the development of dependence on opioids. The present study examined effects of dermal pretreatment with methyl parathion (MP), an acetylcholinesterase inhibitor, on the development of physical dependence on morphine. Opioid dependence was induced by continuous intracerebroventricular (i.c.v.) infusion of morphine (26 nmol/μl/h) for 3 days in adult male Sprague-Dawley rats. Each rat received two doses of MP, 12.5 mg/kg, d...

Investigating correlation between legal and physical property: possibilities and constraints

Science.gov (United States)

Dimopoulou, E.; Kitsakis, D.; Tsiliakou, E.

2015-06-01

Contemporary urban environment is characterized by complexity and mixed use of space, in which overlapping land parcels and different RRRs (Rights, Restrictions and Responsibilities) are frequent phenomena. Internationally, real property legislation either focuses on surface property or has introduced individual 3D real property units. The former approach merely accommodates issues related to subdivision, expropriation and transactions on part of the real property above or below surface, while the latter provides for defining and registering 3D real property units. National laws require two-dimensional real property descriptions and only a limited number of jurisdictions provide for threedimensional data presentation and recording. International awareness on 3D Cadastre may be apparent through the proposals for transition of existing cadastral systems to 3D along with legal amendments improving national 3D Cadastre legislation. Concurrently the use of appropriate data sources and the correct depiction of 3D property units' boundaries and spatial relationships need to be addressed. Spatial relations and constraints amongst real world objects could be modeled geometrically and topologically utilizing numerous modeling tools, e.g. CityGML, BIM and further sophisticated 3D software or by adapting international standards, e.g. LADM. A direct correlation between legal and physical property should be based on consistent geometry between physical and legal space, improving the accuracy that legal spaces' volumes or locations are defined. To address these issues, this paper investigates correlation possibilities and constraints between legal and physical space of typical 3D property cases. These cases comprise buildings or their interior spaces with mixed use, as well as complex structures described by explicit facade patterns, generated by procedural or by BIM ready 3D models. The 3D models presented are evaluated, regarding compliancy to physical or legal reality.

Preparation and physical properties of vapour-deposited carbon-carbon composites

International Nuclear Information System (INIS)

Loll, Philippe

1976-01-01

In its first part, this research thesis reports a bibliographical study on methods of preparation of various types of vapour-deposited (CVD) carbons, and the author notices that only structure and texture properties of these macroscopically homogeneous pyro-carbons have been studied in detail. For a better understanding of the behaviour of carbon-carbon composites, this thesis thus reports the study of the relationships between physical properties, macroscopic texture and microscopic structure. A densification installation and methods of characterisation have been developed. The fabrication process and its installation are presented (oven with its temperature and gas rate controls, study of its thermal gradient, substrate, heat treatments), and the study and characterisation of carbon-carbon composites are reported: structure and texture properties (studied by optic and scanning electronic microscopy, density measurements, and X-ray diffraction), physical properties (electronic paramagnetic resonance, static magnetism, electric and thermal conductivity). In the last part, the author comments and discusses the obtained results: conditions of preparation, existence, physical properties of the different observed microstructures [fr

Study on Physical Properties and Chemical Composition of Some Myanmar Gems

International Nuclear Information System (INIS)

Kyaw Myint Htoo; Tun Khin; Sein Htoon

2004-05-01

Physical properties of some Myanmar gems were studied by using refractometer, dichroscope, polariscope, SG test, UV test and microscope. Then, chemical composition were investigated by XRF-technique. After that, gem identification, evaluation, colour improvement were studied according to these physical properties and chemical composition

Physical Properties of Hanford Transuranic Waste Sludge

International Nuclear Information System (INIS)

Poloski, A. P.

2004-01-01

This project has two primary objectives. The first is to understand the physical properties and behavior of the Hanford transuranic (TRU) tank sludges under conditions that might exist during retrieval, treatment, packaging, and transportation for disposal at WIPP. The second primary objective is to develop a fundamental understanding of these sludge suspensions by correlating the macroscopic properties with particle interactions occurring at the colloidal scale in the various liquid media. The results of this research effort will enhance the existing understanding of agglomeration phenomena and the properties of complex colloidal suspensions. In addition, the knowledge gained and capabilities developed during this effort will aid in the development and optimization of techniques to process the wastes at various DOE sites. These objectives will be accomplished by: (1) characterizing the TRU sludges contained in the Hanford tanks that are intended for shipment to WIPP; (2) determining the physical behavior of the Hanford TRU tank sludges under conditions that might exist during treatment and packaging; (3) and modeling the retrieval, treatment, and packaging operations that will be performed at Hanford to dispose of TRU tank sludges

Mechanical and physical properties of agro-based fiberboard

Science.gov (United States)

S. Lee; T.F. Shupe; C.Y. Hse

2006-01-01

In order to better utilize agricultural fibers as an alternative resource for composite panels, several variables were investigated to improve mechanical and physical properties of agm-based fiberboard. This study focused on the effect of fiber morphology, slenderness ratios (UD), and fiber mixing combinations on panel properties. The panel construction types were also...

Soil physical properties on Venezuelan steeplands: Applications to soil conservation planning

International Nuclear Information System (INIS)

Delgado, F.

2004-01-01

This paper presents a framework to support decision making for soil conservation on Venezuelan steeplands. The general approach is based on the evaluation of two important land qualities: soil productivity and soil erosion risk, both closely related to soil physical properties. Soil productivity can be estimated from soil characteristics such as soil air-water relationships, soil impedances and soil fertility. On the other hand, soil erosion risk depends basically on soil hydrologic properties, rainfall aggressiveness and terrain slope. Two indexes are obtained from soil and land characteristics: soil productivity index (PI) and erosion risk index (ERI), each one evaluates the respective land quality. Subsequently, a matrix with these two qualities shows different land classes as well as soil conservation priorities, conservation requirements and proposed land uses. The paper shows also some applications of the soil productivity index as an approach to evaluate soil loss tolerance for soil conservation programs on tropical steeplands. (author)

Physical properties of biological entities: an introduction to the ontology of physics for biology.

Directory of Open Access Journals (Sweden)

Daniel L Cook

Full Text Available As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities-molecules, cells, organs-are well-established, there are no principled ontologies of physical properties-energies, volumes, flow rates-of those entities. In this paper, we introduce the Ontology of Physics for Biology (OPB, a reference ontology of classical physics designed for annotating biophysical content of growing repositories of biomedical datasets and analytical models. The OPB's semantic framework, traceable to James Clerk Maxwell, encompasses modern theories of system dynamics and thermodynamics, and is implemented as a computational ontology that references available upper ontologies. In this paper we focus on the OPB classes that are designed for annotating physical properties encoded in biomedical datasets and computational models, and we discuss how the OPB framework will facilitate biomedical knowledge integration.

Physical properties of biological entities: an introduction to the ontology of physics for biology.

Science.gov (United States)

Cook, Daniel L; Bookstein, Fred L; Gennari, John H

2011-01-01

As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities-molecules, cells, organs-are well-established, there are no principled ontologies of physical properties-energies, volumes, flow rates-of those entities. In this paper, we introduce the Ontology of Physics for Biology (OPB), a reference ontology of classical physics designed for annotating biophysical content of growing repositories of biomedical datasets and analytical models. The OPB's semantic framework, traceable to James Clerk Maxwell, encompasses modern theories of system dynamics and thermodynamics, and is implemented as a computational ontology that references available upper ontologies. In this paper we focus on the OPB classes that are designed for annotating physical properties encoded in biomedical datasets and computational models, and we discuss how the OPB framework will facilitate biomedical knowledge integration. © 2011 Cook et al.

Physical activity moderates the association between nicotine dependence and depression among U.S. smokers.

Science.gov (United States)

Loprinzi, Paul D; Walker, Jerome F; Kane, Christy; Cardinal, Bradley J

2014-01-01

Research demonstrates that nicotine dependence and depression are associated and that physical activity is effective in reducing depression symptoms. However, our understanding of the potential beneficial effects of physical activity on depression in current smokers is more limited. The purpose of this study was to examine whether physical activity moderates the association between nicotine dependence and depression in U.S. smokers. Cross-sectional. National Health and Nutrition Examination Survey 2005-2006. Four hundred forty-one current adult smokers. Participants wore an accelerometer for at least 4 days and completed questionnaires to assess nicotine dependence and depression. Effect modification and statistical interaction models were used. Both models were significant. With regard to the statistical interaction model, and after controlling for age, gender, race/ethnicity, education, comorbidity index, homocysteine, cotinine, total cholesterol, sedentary behavior, and vitamins C, D, and E, objectively measured physical activity moderated the association between nicotine dependence and depression (interaction variable: odds ratio = 3.43; 95% confidence interval: 1.02-11.51; p = .04). In this national sample of current smokers, physical activity moderated the association between nicotine dependence and depression. These results suggest that those individuals with nicotine dependence and who are less physically active are more likely to be depressed than what would be expected on the basis of the individual effects of nicotine and physical inactivity separately.

Temperature-Dependent Dielectric Properties of Al/Epoxy Nanocomposites

Science.gov (United States)

Wang, Zijun; Zhou, Wenying; Sui, Xuezhen; Dong, Lina; Cai, Huiwu; Zuo, Jing; Chen, Qingguo

2016-06-01

Broadband dielectric spectroscopy was carried out to study the transition in electrical properties of Al/epoxy nanocomposites over the frequency range of 1-107 Hz and the temperature range of -20°C to 200°C. The dielectric permittivity, dissipation factor, and electrical conductivity of the nanocomposites increased with temperature and showed an abrupt increase around the glass transition temperature ( T g). The results clearly reveal an interesting transition of the electrical properties with increasing temperature: insulator below 70°C, conductor at about 70°C. The behavior of the transition in electrical properties of the nanocomposites was explored at different temperatures. The presence of relaxation peaks in the loss tangent and electric modulus spectra of the nanocomposites confirms that the chain segmental dynamics of the polymer is accompanied by the absorption of energy given to the system. It is suggested that the temperature-dependent transition of the electric properties in the nanocomposite is closely associated with the α-relaxation. The large increase in the dissipation factor and electric conductivity depends on the direct current conduction of thermally activated charge carriers resulting from the epoxy matrix above T g.

Effects of gamma rays on the physical and mechanical properties of hide

International Nuclear Information System (INIS)

Sutrisno Puspodikoro.

1976-01-01

The effect of gamma rays on the physical and mechanical properties of hide has been studied, using Gammacell 220 as an irradiator. The determination of the physical and mechanical properties of the irradiated hide was carried out by Balai Penelitian Kulit (Leather Research Institute) at Yogyakarta. Experiments show that up to a certain dose of irradiation, favourable effects can be obtained, while higher doses impair the physical and mechanical properties of the leather raw materials. (author)

Analysis of stress intensity factor for a Griffith crack opened under constant pressure in a plate with temperature dependent properties

International Nuclear Information System (INIS)

Hata, Toshiaki

1982-01-01

Recently, the research on the thermal stress of structural materials has become important with the progress of nuclear reactor technology. In the case of large temperature gradient, the change of the physical properties of materials must be taken into account. The thermal stress analysis for the things with cracks taking the temperature dependence of properties into account has scarcely been carried out. In this report, the general method of solution of three-dimensional problems using perturbation method and the extension of thermo-elastic displacement potential method is shown for the case in which Young's modulus changes according to the exponential function of temperature. Moreover, using this method, the effect of the temperature dependence of properties on the stress intensity factor of the cracks subjected to internal pressure in a strip exposed to linear thermal flow was clarified. In the analysis, Young's modulus, the coefficient of linear thermal expansion and thermal conductivity were assumed to be dependent on temperature. The method of solution, the analysis of stress intensity factor considering the change of properties due to temperature, and the numerical calculation for a square plate with a crack are explained. (Kako, I.)

Studies on Physical and Sensory Properties of Premium Vanilla Ice Cream Distributed in Korean Market.

Science.gov (United States)

Choi, Mi-Jung; Shin, Kwang-Soon

2014-01-01

The object of this study was to investigate the difference in physical and sensory properties of various premium ice creams. The physical properties of the various ice creams were compared by manufacturing brand. The water contents of the samples differed, with BR having the highest value at 60.5%, followed by NT and CS at 57.8% and 56.9%, respectively. The higher the water content, the lower Brix and milk fat contents in all samples. The density of the samples showed almost similar values in all samples (p>0.05). The viscosity of each ice cream had no effect on the water content in any of the brands. Before melting of the ice cream, the total color difference was dependent on the lightness, especially in the vanilla ice cream, owing to the reflection of light on the surface of the ice crystals. The CS product melted the fastest. In the sensory test, CS obtained a significantly higher sweetness intensity score but a lower score for color intensity, probably due to the smaller difference in total color, by which consumers might consider the color of CS as less intense. From this study, the cold chain system for ice cream distribution might be important to decide the physical properties although the concentration of milk fat is key factor in premium ice cream.

Some Physical and Mechanical Properties of Daniellia Ogea Harms ...

African Journals Online (AJOL)

ADOWIE PERE

density were the physical properties tested while the mechanical properties were the modulus of rupture ... 300kN capacity of the food laboratory of the department of Agriculture of the University. ..... Negro, F; Cremonini, C; Zanuttini, R (2013).

Physical and Chemical Properties of Soils under Contrasting Land ...

African Journals Online (AJOL)

Physical and Chemical Properties of Soils under Contrasting Land Use ... the aim of understanding the response of the soil to different management practices over time. ... The soil chemical properties studied were soil pH, organic carbon, total ...

Context-dependent utility overrides absolute memory as a determinant of choice

OpenAIRE

Pompilio, Lorena; Kacelnik, Alex

2009-01-01

A core problem of decision theories is that although decisionmakers’ preferences depend on learning, their choices could be driven either by learned representations of the physical properties of each alternative (for instance reward sizes) or of the benefit (utility and fitness) experienced from them. Physical properties are independent of the subject’s state and context, but utility depends on both. We show that starlings’ choices are better explained by memory for context-dependent utility ...

Structure and physical properties of bio membranes and model membranes

International Nuclear Information System (INIS)

Tibor Hianik

2006-01-01

Bio membranes belong to the most important structures of the cell and the cell organelles. They play not only structural role of the barrier separating the external and internal part of the membrane but contain also various functional molecules, like receptors, ionic channels, carriers and enzymes. The cell membrane also preserves non-equilibrium state in a cell which is crucial for maintaining its excitability and other signaling functions. The growing interest to the bio membranes is also due to their unique physical properties. From physical point of view the bio membranes, that are composed of lipid bilayer into which are incorporated integral proteins and on their surface are anchored peripheral proteins and polysaccharides, represent liquid s crystal of smectic type. The bio membranes are characterized by anisotropy of structural and physical properties. The complex structure of bio membranes makes the study of their physical properties rather difficult. Therefore several model systems that mimic the structure of bio membranes were developed. Among them the lipid monolayers at an air-water interphase, bilayer lipid membranes, supported bilayer lipid membranes and liposomes are most known. This work is focused on the introduction into the physical word of the bio membranes and their models. After introduction to the membrane structure and the history of its establishment, the physical properties of the bio membranes and their models are stepwise presented. The most focus is on the properties of lipid monolayers, bilayer lipid membranes, supported bilayer lipid membranes and liposomes that were most detailed studied. This lecture has tutorial character that may be useful for undergraduate and graduate students in the area of biophysics, biochemistry, molecular biology and bioengineering, however it contains also original work of the author and his co-worker and PhD students, that may be useful also for specialists working in the field of bio membranes and model

Physical properties of pyrolytically sprayed tin-doped indium oxide coatings

NARCIS (Netherlands)

Haitjema, H.; Elich, J.J.P.

1991-01-01

The optical and electrical properties of tin-doped indium oxide coatings obviously depend on a number of production parameters. This dependence has been studied to obtain a more general insight into the relationships between the various coating properties. The coatings have been produced by spray

Fundamental Constants in Physics and their Time Dependence

CERN Multimedia

CERN. Geneva

2008-01-01

In the Standard Model of Particle Physics we are dealing with 28 fundamental constants. In the experiments these constants can be measured, but theoretically they are not understood. I will discuss these constants, which are mostly mass parameters. Astrophysical measurements indicate that the finestructure constant is not a real constant, but depends on time. Grand unification then implies also a time variation of the QCD scale. Thus the masses of the atomic nuclei and the magnetic moments of the nuclei will depend on time. I proposed an experiment, which is currently done by Prof. Haensch in Munich and his group. The first results indicate a time dependence of the QCD scale. I will discuss the theoretical implications.

Estimation of Physical Properties of Amino Acids by Group-Contribution Method

DEFF Research Database (Denmark)

Jhamb, Spardha Virendra; Liang, Xiaodong; Gani, Rafiqul

2018-01-01

In this paper, we present group-contribution (GC) based property models for estimation of physical properties of amino acids using their molecular structural information. The physical properties modelled in this work are normal melting point (Tm), aqueous solubility (Ws), and octanol....../water partition coefficient (Kow) of amino acids. The developed GC-models are based on the published GC-method by Marrero and Gani (J. Marrero, R. Gani, Fluid Phase Equilib. 2001, 183-184, 183-208) with inclusion of new structural parameters (groups and molecular weight of compounds). The main objective...... of introducing these new structural parameters in the GC-model is to provide additional structural information for amino acids having large and complex structures and thereby improve predictions of physical properties of amino acids. The group-contribution values were calculated by regression analysis using...

Symmetry and physical properties of crystals

CERN Document Server

Malgrange, Cécile; Schlenker, Michel

2014-01-01

Crystals are everywhere, from natural crystals (minerals) through the semiconductors and magnetic materials in electronic devices and computers or piezoelectric resonators at the heart of our quartz watches to electro-optical devices. Understanding them in depth is essential both for pure research and for their applications. This book provides a clear, thorough presentation of their symmetry, both at the microscopic space-group level and the macroscopic point-group level. The implications of the symmetry of crystals for their physical properties are then presented, together with their mathematical description in terms of tensors. The conditions on the symmetry of a crystal for a given property to exist then become clear, as does the symmetry of the property. The geometrical representation of tensor quantities or properties is presented, and its use in determining important relationships emphasized. An original feature of this book is that most chapters include exercises with complete solutions. This all...

Prediction of transport and other physical properties of fluids

CERN Document Server

Bretsznajder, S

1971-01-01

Prediction of Transport and Other Physical Properties of Fluids reviews general methods for predicting the transport and other physical properties of fluids such as gases and liquids. Topics covered range from the theory of corresponding states and methods for estimating the surface tension of liquids to some basic concepts of the kinetic theory of gases. Methods of estimating liquid viscosity based on the principle of additivity are also described. This volume is comprised of eight chapters and opens by presenting basic information on gases and liquids as well as intermolecular forces and con

Physical Principles Pertaining to Ultrasonic and Mechanical Properties of Anisotropic Media and Their Application to Nondestructive Evaluation of Fiber-Reinforced Composite Materials

Science.gov (United States)

Handley, Scott Michael

The central theme of this thesis is to contribute to the physics underlying the mechanical properties of highly anisotropic materials. Our hypothesis is that a fundamental understanding of the physics involved in the interaction of interrogating ultrasonic waves with anisotropic media will provide useful information applicable to quantitative ultrasonic measurement techniques employed for the determination of material properties. Fiber-reinforced plastics represent a class of advanced composite materials that exhibit substantial anisotropy. The desired characteristics of practical fiber -reinforced composites depend on average mechanical properties achieved by placing fibers at specific angles relative to the external surfaces of the finished part. We examine the physics underlying the use of ultrasound as an interrogation probe for determination of ultrasonic and mechanical properties of anisotropic materials such as fiber-reinforced composites. Fundamental constituent parameters, such as elastic stiffness coefficients (c_{rm IJ}), are experimentally determined from ultrasonic time-of-flight measurements. Mechanical moduli (Poisson's ratio, Young's and shear modulus) descriptive of the anisotropic mechanical properties of unidirectional graphite/epoxy composites are obtained from the ultrasonically determined stiffness coefficients. Three-dimensional visualizations of the anisotropic ultrasonic and mechanical properties of unidirectional graphite/epoxy composites are generated. A related goal of the research is to strengthen the connection-between practical ultrasonic nondestructive evaluation methods and the physics underlying quantitative ultrasonic measurements for the assessment of manufactured fiber-reinforced composites. Production defects such as porosity have proven to be of substantial concern in the manufacturing of composites. We investigate the applicability of ultrasonic interrogation techniques for the detection and characterization of porosity in

Assessing the physical-chemical properties and stability of dapivirine-loaded polymeric nanoparticles.

Science.gov (United States)

das Neves, José; Amiji, Mansoor; Bahia, Maria Fernanda; Sarmento, Bruno

2013-11-18

Nanocarriers may provide interesting delivery platforms for microbicide drugs and their characterization should be addressed early in development. Differently surface-engineered dapivirine-loaded, poly(epsilon-caprolactone) (PCL)-based nanoparticles (NPs) were obtained by nanoprecipitation using polyethylene oxide (PEO), sodium lauryl sulfate (SLS), or cetyltrimethylammonium bromide (CTAB) as surface modifiers. Physical-chemical properties of NP aqueous dispersions were evaluated upon storage at -20-40 °C for one year. NPs presented 170-200 nm in diameter, roundish-shape, low polydispersity index (≤0.18), and high drug association efficiency (≥97%) and loading (≥12.7%). NPs differed in zeta potential, depending on surface modifier (PEO: -27.9 mV; SLS: -54.7 mV; CTAB: +42.4 mV). No interactions among formulation components were detected by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR), except for SLS-PCL NPs. Colloidal properties of NPs were lost at -20 °C storage. Negatively charged NPs were stable up to one year at 5-40°C; as for CTAB-PCL NPs, particle aggregation was observed from 30 to 90 days of storage depending on temperature. Colloidal instability affected the in vitro drug release of CTAB-PCL NPs after 360 days. In any case, no degradation of dapivirine was apparent. Overall, PEO-PCL and SLS-PCL NPs presented suitable properties as nanocarriers for dapivirine. Conversely, CTAB-PCL NPs require additional strategies in order to increase stability. Copyright © 2013 Elsevier B.V. All rights reserved.

Temperature-dependent electrical property transition of graphene oxide paper

International Nuclear Information System (INIS)

Huang Xingyi; Jiang Pingkai; Zhi Chunyi; Golberg, Dmitri; Bando, Yoshio; Tanaka, Toshikatsu

2012-01-01

Reduction of graphene oxide is primarily important because different reduction methods may result in graphene with totally different properties. For systematically exploring the reduction of graphene oxide, studies of the temperature-dependent electrical properties of graphene oxide (GO) are urgently required. In this work, for the first time, broadband dielectric spectroscopy was used to carry out an in situ investigation on the transition of the electrical properties of GO paper from −40 to 150 °C. The results clearly reveal a very interesting four-stage transition of electrical properties of GO paper with increasing temperature: insulator below 10 °C (stage 1), semiconductor at between 10 and 90 °C (stage 2), insulator at between 90 and 100 °C (stage 3), and semiconductor again at above 100 °C (stage 4). Subsequently, the transition mechanism was discussed in combination with detailed dielectric properties, microstructure and thermogravimetric analyses. It is suggested that the temperature-dependent transition of electronic properties of GO is closely associated with the ion mobility, water molecules removal and the reduction of GO in the GO paper. Most importantly, the present work clearly demonstrates the reduction of GO paper starts at above 100 °C. (paper)

PSYCHOLOGICAL AND SOCIODEMOGRAPHIC CHARACTERISTICS AND DEVELOPMENT OF PHYSICAL EXERCISE DEPENDENCE

Directory of Open Access Journals (Sweden)

Almedina Numanović

Full Text Available ABSTRACT Introduction: Excessive physical exercise combined with certain psychic and sociodemographic factors can lead to dependence. Objective: To examine which factors lead to the emergence of exercise dependence. Methods: Sample consisted of 103 men (mean age 27.3 years, SD 6.127 who performed exercises at gyms at least three times a week in the last year or more in Novi Pazar, Sjenica, Raska and Tutin, Serbia. Participants completed questionnaires and took appropriate tests. Results: Our results showed that there is no association between exercise dependence and financial status, number of siblings, level of education, family stability, health, and medication use among the interviewees. However, it was found that the degree of exercise dependence is associated with marital status and problems with the law. Regression analysis showed that body dysmorphia, body mass index and aggressiveness are better predictors of exercise dependence. Conclusion: People whose self-perception is dismorphic have lower self-esteem, and exercise in gyms to improve their physical appearance. If we consider other characteristics, such as unfavorable BMI, problems with the lаw and being single, it is hardly surprising these individuals cross the line between healthy exercise and exercise dependence. An important finding is that aggressiveness and exercise dependence are related to problems with the law due to aggression, and body dysmorphia. Level of Evidence; Diagnostic studies - Investigating a diagnostic test.

Autoinactivation of the stargazin-AMPA receptor complex: subunit-dependency and independence from physical dissociation.

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Artur Semenov

Full Text Available Agonist responses and channel kinetics of native α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA receptors are modulated by transmembrane accessory proteins. Stargazin, the prototypical accessory protein, decreases desensitization and increases agonist potency at AMPA receptors. Furthermore, in the presence of stargazin, the steady-state responses of AMPA receptors show a gradual decline at higher glutamate concentrations. This "autoinactivation" has been assigned to physical dissociation of the stargazin-AMPA receptor complex and suggested to serve as a protective mechanism against overactivation. Here, we analyzed autoinactivation of GluA1-A4 AMPA receptors (all flip isoform expressed in the presence of stargazin. Homomeric GluA1, GluA3, and GluA4 channels showed pronounced autoinactivation indicated by the bell-shaped steady-state dose response curves for glutamate. In contrast, homomeric GluA2i channels did not show significant autoinactivation. The resistance of GluA2 to autoinactivation showed striking dependence on the splice form as GluA2-flop receptors displayed clear autoinactivation. Interestingly, the resistance of GluA2-flip containing receptors to autoinactivation was transferred onto heteromeric receptors in a dominant fashion. To examine the relationship of autoinactivation to physical separation of stargazin from the AMPA receptor, we analyzed a GluA4-stargazin fusion protein. Notably, the covalently linked complex and separately expressed proteins expressed a similar level of autoinactivation. We conclude that autoinactivation is a subunit and splice form dependent property of AMPA receptor-stargazin complexes, which involves structural rearrangements within the complex rather than any physical dissociation.

Thermo-Physical Properties of Kenaf-Filled Acrylonitrile Butadiene Styrene Composites

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Nikmatin Siti

2017-01-01

Full Text Available Studies on advantageous of natural fillers incorporated into polymer composites on thermo-physical and mechanical properties are still intensively investigated. Several evidences suggest that the natural fillers with small contents combined with polymer increase their composite properties. We thus investigate thermo-physical properties of kenaf-filled acrylonitrile butadiene styrene (ABS composites. ABS with 5% kenaf microparticle size (ABS/K5, ABS with 5% kenaf short fiber (ABS/KSF5, and recycled ABS with 5% kenaf microparticle size (RABS/K5 were manufactured. Granular composites were manufactured by the twin screw extruder. Composite properties in terms of X-ray diffractions, surface morphologies, and thermal behaviors were investigated. The present work found that ABS/KSF5 has the highest degree of crystallinity compared to others. No significant difference was found in terms of thermal properties of the composites.

Elastic properties

International Nuclear Information System (INIS)

Ledbetter, H.M.

1983-01-01

This chapter investigates the following five aspects of engineering-material solid-state elastic constants: general properties, interrelationships, relationships to other physical properties, changes during cooling from ambient to near-zero temperature, and near-zero-temperature behavior. Topics considered include compressibility, bulk modulus, Young's modulus, shear modulus, Poisson's ratio, Hooke's law, elastic-constant measuring methods, thermodynamic potentials, higher-order energy terms, specific heat, thermal expansivity, magnetic materials, structural phase transitions, polymers, composites, textured aggregates, and other-phenomena correlations. Some of the conclusions concerning polycrystalline elastic properties and their temperature dependence are: elastic constants are physical, not mechanical, properties which relate thermodynamically to other physical properties such as specific heat and thermal expansivity; elastic constants at low temperatures are nearly temperature independent, as required by the third law of thermodynamics; and elastic constants can be used to study directional properties of materials, such as textured aggregates and composites

Temperature dependence of PZT film optical properties

Czech Academy of Sciences Publication Activity Database

Deineka, Alexander; Jastrabík, Lubomír; Suchaneck, G.; Gerlach, G.

11-12, - (2001), s. 352-354 ISSN 0447-6441 R&D Projects: GA ČR GA202/00/1425; GA MŠk LN00A015 Institutional research plan: CEZ:AV0Z1010914 Keywords : refractive index profile * PZT film * temperature dependence of optical properties Subject RIV: BH - Optics, Masers, Lasers

Physical properties of the planet Mercury

Science.gov (United States)

Clark, Pamela E.

1988-01-01

The global physical properties of Mercury are summarized with attention given to its figure and orbital parameters. The combination of properties suggests that Mercury has an extensive iron-rich core, possibly with a still-functioning dynamo, which is 42 percent of the interior by volume. Mercury's three major axes are comparable in size, indicating that the planet is a triaxial ellipsoid rather than an oblate spheroid. In terms of the domination of its surface by an intermediate plains terrane, it is more Venus- or Mars-like; however, due to the presence of a large metallic magnetic core, its interior may be more earth-like.

Spatial Dependence of Physical Attributes and Mechanical Properties of Ultisol in a Sugarcane Field.

Science.gov (United States)

Tavares, Uilka Elisa; Rolim, Mário Monteiro; de Oliveira, Veronildo Souza; Pedrosa, Elvira Maria Regis; Siqueira, Glécio Machado; Magalhães, Adriana Guedes

2015-01-01

This study investigates the effect of conventional tillage and application of the monoculture of sugar cane on soil health. Variables like density, moisture, texture, consistency limits, and preconsolidation stress were taken as indicators of soil quality. The measurements were made at a 120 × 120 m field cropped with sugar cane under conventional tillage. The objective of this work was to characterize the soil and to study the spatial dependence of the physical and mechanical attributes. Then, undisturbed soil samples were collected to measure bulk density, moisture content and preconsolidation stress and disturbed soil samples for classification of soil texture, and consistency limits. The soil texture indicated that soil can be characterized as sandy clay soil and a sandy clay loam soil, and the consistency limits indicated that the soil presents an inorganic low plasticity clay. The preconsolidation tests tillage in soil moisture content around 19% should be avoided or should be chosen a management of soil with lighter vehicles in this moisture content, to avoid risk of compaction. Using geostatistical techniques mapping was possible to identify areas of greatest conservation soil and greater disturbance of the ground.

Fingerprinting: Modelling and mapping physical top soil properties with the Mole

Science.gov (United States)

Loonstra, Eddie; van Egmond, Fenny

2010-05-01

The Mole is a passive gamma ray soil sensor system. It is designed for the mobile collection of radioactive energy stemming from soil. As the system is passive, it only measures energy that reaches the surface of soil. In general, this energy comes from upto 30 to 40 cm deep, which can be considered topsoil. The gathered energy spectra are logged every second, are processed with the method of Full Spectrum Analysis. This method uses all available spectral data and processes it with a Chi square optimalisation using a set of standard spectra into individual nuclide point data. A standard spectrum is the measured full spectrum of a specific detector derived when exposed to 1 Bq/kg of a nuclide. With this method the outcome of the surveys become quantitative.The outcome of a field survey with the Mole results in a data file containing point information of position, Total Counts and the decay products of 232Th, 238U, 40K and 137Cs. Five elements are therefor available for the modelling of soil properties. There are several ways for the modelling of soil properties with sensor derived gamma ray data. The Mole generates ratio scale output. For modelling a quantitative deterministic approach is used based on sample locations. This process is called fingerprinting. Fingerprinting is a comparison of the concentration of the radioactive trace elements and the lab results (pH, clay content, etc.) by regression analysis. This results in a mathematical formula describing the relationship between a dependent and independent property. The results of the sensor readings are interpolated into a nuclide map with GIS software. With the derived formula a soil property map is composed. The principle of fingerprinting can be applied on large geographical areas for physical soil properties such as clay, loam or sand (50 micron), grain size and organic matter. Collected sample data of previous field surveys within the same region can be used for the prediction of soil properties elsewhere

Effect of porous zeolite on temperature-dependent physical properties of polypropylene/octadecane (PP/OD composite films

Directory of Open Access Journals (Sweden)

D. Kim

2018-07-01

Full Text Available Polymeric materials with temperature-dependent gas permeabilities using a phase change material are designed and their applicability as a packaging system investigated. Polypropylene/octadecane/zeolite (PP/OD/ZL composite films were prepared via extrusion process. ZL was used as a filler to enhance the dispersion and interfacial interaction between the OD and the PP originating from different flowabilities during the extrusion process. (FTIR and (WAXD analyses showed that the incorporation of ZL increased the interfacial interaction between PP and OD, resultantly enhancing the thermal stability, mechanical properties, and the oxygen transmittance rate and mechanical properties after contact with food simulants and thermal treatment. When the temperature was elevated from 10 to 30 °C, oxygen and water vapor transmittance rate of the composite films increased sharply because of the influence of the OD content. It was surmised that temperaturedependent permeation jump caused by increasing of segmental mobility of OD phase and converting the crystalline structure to an amorphous one of OD phase in the composite films. However, the permeation jump in the composite films was weakened as the ZL content increased. These results are related to changes in the interfacial interaction and crystallinity in the composite films due to the addition of ZL.

Effect of water phase transition on dynamic ruptures with thermal pressurization: Numerical simulations with changes in physical properties of water

Science.gov (United States)

Urata, Yumi; Kuge, Keiko; Kase, Yuko

2015-02-01

Phase transitions of pore water have never been considered in dynamic rupture simulations with thermal pressurization (TP), although they may control TP. From numerical simulations of dynamic rupture propagation including TP, in the absence of any water phase transition process, we predict that frictional heating and TP are likely to change liquid pore water into supercritical water for a strike-slip fault under depth-dependent stress. This phase transition causes changes of a few orders of magnitude in viscosity, compressibility, and thermal expansion among physical properties of water, thus affecting the diffusion of pore pressure. Accordingly, we perform numerical simulations of dynamic ruptures with TP, considering physical properties that vary with the pressure and temperature of pore water on a fault. To observe the effects of the phase transition, we assume uniform initial stress and no fault-normal variations in fluid density and viscosity. The results suggest that the varying physical properties decrease the total slip in cases with high stress at depth and small shear zone thickness. When fault-normal variations in fluid density and viscosity are included in the diffusion equation, they activate TP much earlier than the phase transition. As a consequence, the total slip becomes greater than that in the case with constant physical properties, eradicating the phase transition effect. Varying physical properties do not affect the rupture velocity, irrespective of the fault-normal variations. Thus, the phase transition of pore water has little effect on dynamic ruptures. Fault-normal variations in fluid density and viscosity may play a more significant role.

Temperature-dependent dynamic mechanical properties of magnetorheological elastomers under magnetic field

Energy Technology Data Exchange (ETDEWEB)

Ju, Benxiang, E-mail: jubenxiang@qq.com [National Instrument Functional Materials Engineering Technology Research Center, Chongqing 400707 (China); Tang, Rui; Zhang, Dengyou; Yang, Bailian [National Instrument Functional Materials Engineering Technology Research Center, Chongqing 400707 (China); Yu, Miao; Liao, Changrong [College of Optoelectronic Engineering, Chongqing University, Chongqing 400044 (China)

2015-01-15

Both anisotropic and isotropic magnetorheological elastomer (MRE) samples were fabricated by using as-prepared polyurethane (PU) matrix and carbonyl iron particles. Temperature-dependent dynamic mechanical properties of MRE were investigated and analyzed. Due to the unique structural features of as-prepared matrix, temperature has a greater impact on the properties of as-prepared MRE, especially isotropic MRE. With increasing of temperature and magnetic field, MR effect of isotropic MRE can reach up to as high as 4176.5% at temperature of 80 °C, and the mechanism of the temperature-dependent in presence of magnetic field was discussed. These results indicated that MRE is a kind of temperature-dependent material, and can be cycled between MRE and MR plastomer (MRP) by varying temperature. - Highlights: • Both anisotropic and isotropic MRE were fabricated by using as-prepared matrix. • Temperature-dependent properties of MRE under magnetic field were investigated. • As-prepared MRE can transform MRE to MRP by adjusting temperature.

TaSiN nanocomposite thin films: Correlation between structure, chemical composition, and physical properties

International Nuclear Information System (INIS)

Ramírez, G.; Oezer, D.; Rivera, M.; Rodil, S.E.; Sanjinés, R.

2014-01-01

The structural and electronic properties of fcc-TaN/SiN x nanocomposite thin films deposited by reactive magnetron sputtering have been investigated as function of the N and Si contents. Our studies have been mainly focused on three different types of nanocomposite Ta x Si y N z films based on: nitrogen deficient fcc-TaN 0.88 , nearly stoichiometric fcc-TaN, and over-stoichiometric fcc-TaN 1.2 with the Si contents in the range from 0 to about 15 at.%. The optical properties were investigated by ellipsometric measurements, while the DC. electrical resistivity was measured using the van der Pauw configuration at 300 K. The optical measurements were interpreted using the standard Drude–Lorentz model. The results showed that the electronic properties are closely correlated with both the compositional and the structural modifications of the Ta x Si y N z films induced by the addition of Si atoms, and also depending on the stoichiometry of the starting fcc-TaN system. Thus, depending on both the nitrogen and the silicon contents, the fcc-Ta x Si y N z films can exhibit room temperature resistivity values ranging from 10 2 μΩ cm to about 6 × 10 4 μΩ cm. - Highlights: • TaSiN films were grown using dual magnetron sputtering system. • The physical and structural properties were correlated with the deposition parameters. • The electrical properties were influenced by the nitrogen and silicon contents on the films

Natural convection in square enclosures differentially heated at sides using alumina-water nanofluids with temperature-dependent physical properties

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Cianfrini Marta

2015-01-01

Full Text Available Laminar natural convection of Al2O3 + H2O nanofluids inside square cavities differentially heated at sides is studied numerically. A computational code based on the SIMPLE-C algorithm is used for the solution of the system of the mass, momentum and energy transfer governing equations. Assuming that the nanofluid behaves like a single-phase fluid, these equations are the same as those valid for a pure fluid, provided that the thermophysical properties appearing in them are the nanofluid effective properties. The thermal conductivity and dynamic viscosity of the nanofluid are calculated by means of a couple of empirical equations based on a wide variety of experimental data reported in the literature. The other effective properties are evaluated by the conventional mixing theory. Simulations are performed for different values of the nanoparticle volume fraction in the range 0-0.06, the diameter of the suspended nanoparticles in the range 25-100 nm, the temperature of the cooled sidewall in the range 293-313 K, the temperature of the heated sidewall in the range 298-343 K, and the Rayleigh number of the base fluid in the range 103-107. All computations are executed in the hypothesis of temperature-dependent effective properties. The main result obtained is the existence of an optimal particle loading for maximum heat transfer, that is found to increase as the size of the suspended nanoparticles is decreased, and the nanofluid average temperature is increased.

Size- and shape-dependent surface thermodynamic properties of nanocrystals

Science.gov (United States)

Fu, Qingshan; Xue, Yongqiang; Cui, Zixiang

2018-05-01

As the fundamental properties, the surface thermodynamic properties of nanocrystals play a key role in the physical and chemical changes. However, it remains ambiguous about the quantitative influence regularities of size and shape on the surface thermodynamic properties of nanocrystals. Thus by introducing interface variables into the Gibbs energy and combining Young-Laplace equation, relations between the surface thermodynamic properties (surface Gibbs energy, surface enthalpy, surface entropy, surface energy and surface heat capacity), respectively, and size of nanocrystals with different shapes were derived. Theoretical estimations of the orders of the surface thermodynamic properties of nanocrystals agree with available experimental values. Calculated results of the surface thermodynamic properties of Au, Bi and Al nanocrystals suggest that when r > 10 nm, the surface thermodynamic properties linearly vary with the reciprocal of particle size, and when r < 10 nm, the effect of particle size on the surface thermodynamic properties becomes greater and deviates from linear variation. For nanocrystals with identical equivalent diameter, the more the shape deviates from sphere, the larger the surface thermodynamic properties (absolute value) are.

Psychiatric Comorbidity and Physical Correlates in Alcohol-dependent Patients.

Science.gov (United States)

Gauba, Deepak; Thomas, Pramod; Balhara, Yatan P S; Deshpande, Smita N

2016-01-01

To examine the prevalence and pattern of comorbidity in alcohol dependence and its relationship with physical and laboratory findings. Eighty males with alcohol dependence were examined using the Hindi version of Diagnostic Interview for Genetic Studies, the International Classification of Disease-10 th Edition Personality Disorder Examination, Alcohol Use Disorder Identification Test for alcohol use, global assessment of functioning, blood sampling electrocardiogram, and ultrasonogram. Eighty-seven percent had a comorbid Axis I or an Axis II psychiatric disorder, over 78% had nicotine dependence, and 56% had comorbid Axis II disorder, antisocial personality being the most common. Gamma glutamyl transpeptidase levels were significantly associated with comorbidity. High comorbidity of Axis I psychiatric disorders was found among persons with alcohol dependence. Axis II disorders were also present.

Influence of Cellulosic Fibres on the Physical Properties of Fibre Cement Composites

Science.gov (United States)

Hospodarova, V.; Stevulova, N.; Vaclavik, V.; Dvorsky, T.

2017-10-01

Nowadays, there are new approaches directing to processing of non-conventional fibre-cement composites for application in the housing construction. Vegetable cellulosic fibres coming from natural resources used as reinforcement in cost-effective and environmental friendly building products are in the spotlight. The applying of natural fibres in cement based composites is narrowly linked to the ecological building sector, where a choice of materials is based on components including recyclable, renewable raw materials and low-resource manufacture techniques. In this paper, two types of cellulosic fibres coming from wood pulp and recycled waste paper with 0.2%; 0.3% and 0.5% of fibre addition into cement mixtures were used. Differences in the physical characteristics (flowability, density, coefficient of thermal conductivity and water absorbability) of 28 days hardened fibre-cement composites are investigated. Addition of cellulosic fibres to cement mixture caused worsening the workability of fresh mixture as well as absorbability of hardened composites due to hydrophilic nature of biomaterial, whereas density and thermal conductivity of manufactured cement based fibre plaster are enhanced. The physical properties of cement plasters based on cellulosic fibres depend on structural, physical characteristics of cellulosic fibres, their nature and processing.

The plutonium: brief presentation of its nuclear, physical and chemical properties

International Nuclear Information System (INIS)

Madic, C.

1993-01-01

In this text we give a brief presentation of the nuclear properties (isotopes, isotopic composition of spent fuels, decay), of the physical properties (phase diagrams, alloys) and of the chemical properties (complexes, solvent extraction) of the plutonium

Numerical and physical testing of upscaling techniques for constitutive properties

International Nuclear Information System (INIS)

McKenna, S.A.; Tidwell, V.C.

1995-01-01

This paper evaluates upscaling techniques for hydraulic conductivity measurements based on accuracy and practicality for implementation in evaluating the performance of the potential repository at Yucca Mountain. Analytical and numerical techniques are compared to one another, to the results of physical upscaling experiments, and to the results obtained on the original domain. The results from different scaling techniques are then compared to the case where unscaled point scale statistics are used to generate realizations directly at the flow model grid-block scale. Initital results indicate that analytical techniques provide upscaling constitutive properties from the point measurement scale to the flow model grid-block scale. However, no single analytic technique proves to be adequate for all situations. Numerical techniques are also accurate, but they are time intensive and their accuracy is dependent on knowledge of the local flow regime at every grid-block

Prediction of thermo-physical properties of liquid formulated products

DEFF Research Database (Denmark)

Mattei, Michele; Conte, Elisa; Kontogeorgis, Georgios

2013-01-01

The objective of this chapter is to give an overview of the models, methods and tools that may be used for the estimation of liquid formulated products. First a classification of the products is given and the thermo-physical properties needed to represent their functions are listed. For each...... property, a collection of the available models are presented according to the property type and the model type. It should be noted, however, that the property models considered or highlighted in this chapter are only examples and are not necessarily the best and most accurate for the corresponding property....

Physical properties of snacks made from cassava leaf flour

Directory of Open Access Journals (Sweden)

Adriana Cristina Ferrari

2014-02-01

Full Text Available The food industry is continually growing with new products becoming available every year. Extrusion combines a number of unit operations in one energy efficient rapid continuous process and can be used to produce a wide variety of snacks foods. The objective of this study was to evaluate the effect of extrusion temperature, screw speed, and amount of cassava leaf flour mixed with cassava starch on the physical properties of extruded snacks processed using a single screw extruder. A central composite rotational design, including three factors with 20 treatments, was used in the experimental design. Dependent variables included the expansion index, specific volume, color, water absorption index, and water solubility index. Among the parameters examined, the amount of cassava leaf flour and extrusion temperature showed significant effects on extruded snack characteristics. Mixtures containing 10% of cassava leaf flour extruded at 100°C and 255 rpm shows favorable levels of expansion, color, water absorption index, and water solubility index.

QUASAR CLUSTERING FROM SDSS DR5: DEPENDENCES ON PHYSICAL PROPERTIES

International Nuclear Information System (INIS)

Shen Yue; Strauss, Michael A.; Lin, Yen-Ting; Bahcall, Neta A.; Ross, Nicholas P.; Schneider, Donald P.; Vanden Berk, Daniel E.; Hall, Patrick B.; Richards, Gordon T.; Weinberg, David H.; Shankar, Francesco; Connolly, Andrew J.; Fan Xiaohui; Hennawi, Joseph F.; Brunner, Robert J.

2009-01-01

Using a homogenous sample of 38,208 quasars with a sky coverage of ∼4000 deg. 2 drawn from the Sloan Digital Sky Survey Data Release Five quasar catalog, we study the dependence of quasar clustering on luminosity, virial black hole (BH) mass, quasar color, and radio loudness. At z 13 h -1 M sun , compared to ∼2 x 10 12 h -1 M sun for radio-quiet quasar hosts at z ∼ 1.5.

Evaluation of anatomical and physical properties of Khaya nthotheca

African Journals Online (AJOL)

The anatomical and physical properties of Khaya anthotheca (Welw.) C. DC wood from the transition forest of middle altitude (zone 1) and the humid dense forest of low altitude (zone 2) in the East of the Democratic Republic of Congo were evaluated to ascertain the effect of growth area on the anatomical and physical ...

Physical Properties of Vegetables as a Basis for Making Decisions on Their Technological Processing (on the Example of Zucchinis

Directory of Open Access Journals (Sweden)

Tetyana Nepochatykh

2017-08-01

Full Text Available The article is devoted to the study of physical properties (porosity, physical and true density of zucchinis of different kinds. Close relationship between these indicators were proven theoretically and practically. It is recommended, considering the dependence of the true density of vegetables on the moisture content, take into account the ratio of bound and free moisture in them, because their density is different in size. This is especially important for the rate of process of diffusion of sugar syrup into raw material during the production of candied fruits.

Computational studies of physical properties of Nb-Si based alloys

Energy Technology Data Exchange (ETDEWEB)

Ouyang, Lizhi [Middle Tennessee State Univ., Murfreesboro, TN (United States)

2015-04-16

The overall goal is to provide physical properties data supplementing experiments for thermodynamic modeling and other simulations such as phase filed simulation for microstructure and continuum simulations for mechanical properties. These predictive computational modeling and simulations may yield insights that can be used to guide materials design, processing, and manufacture. Ultimately, they may lead to usable Nb-Si based alloy which could play an important role in current plight towards greener energy. The main objectives of the proposed projects are: (1) developing a first principles method based supercell approach for calculating thermodynamic and mechanic properties of ordered crystals and disordered lattices including solid solution; (2) application of the supercell approach to Nb-Si base alloy to compute physical properties data that can be used for thermodynamic modeling and other simulations to guide the optimal design of Nb-Si based alloy.

Physical and mechanical properties of gamma radiation cross-linked polyethylene

International Nuclear Information System (INIS)

Gonzalez, Maria E.; Romero, G.; Smolko, Eduardo E.

1999-01-01

Granulated LDPE 2003 polyethylene was extruded and irradiated under nitrogen with 150, 200 and 300 kGy gamma rays doses to produce cross-linking. The study of the physical and mechanical properties shows that the product has a high degree of molecular cross-linking, can be heated up to 200 C for 2 hours without deformation and that the mechanical properties improve. Preliminary aging tests indicate that after heating at 60 C for 4 weeks no physical or mechanical deterioration can be observed. (author)

Physical Properties of Asteroid (10302) 1989 ML, a Potential Spacecraft Target, from Spitzer Observations

Science.gov (United States)

Mueller, Michael; Harris, A. W.

2006-09-01

We report on results from recent Spitzer observations of near-Earth asteroid (10302) 1989 ML, which is among the lowest-ranking objects in terms of the specific momentum Δv required to reach it from Earth. It was originally considered as a target for Hayabusa and is now under consideration as a target of the planned ESA mission Don Quijote. Unfortunately, little is known about the physical properties of 1989 ML, in particular its size and albedo are unknown. Its exhibits an X type reflection spectrum, so depending on its albedo, 1989 ML may be an E, M, or P type asteroid. Provisional results from thermal-infrared observations carried out with Spitzer indicate that the albedo of 1989 ML is compatible with an M- or E-type classification. We will discuss our results and their implications for the physical properties and the rotation period of 1989 ML, and its importance as a potential spacecraft target. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA.

Phase relations, crystal structures and physical properties of nuclear fuels

International Nuclear Information System (INIS)

Tagawa, Hiroaki; Fujino, Takeo; Tateno, Jun

1975-07-01

Phase relations, crystal structures and physical properties of the compounds for nuclear fuels are presented, including melting point, thermal expansion, diffusion and magnetic and electric properties. Emphasis is on oxides, carbides and nitrides of thorium, uranium and plutonium. (auth.)

Synthesis of Silica Nanoparticles by Sol-Gel: Size-Dependent Properties, Surface Modification, and Applications in Silica-Polymer Nano composites-A Review

International Nuclear Information System (INIS)

Ismail, A.R.; Vejayakumaran, P.

2012-01-01

Application of silica nanoparticles as fillers in the preparation of nano composite of polymers has drawn much attention, due to the increased demand for new materials with improved thermal, mechanical, physical, and chemical properties. Recent developments in the synthesis of monodispersed, narrow-size distribution of nanoparticles by sol-gel method provide significant boost to development of silica-polymer nano composites. This paper is written by emphasizing on the synthesis of silica nanoparticles, characterization on size-dependent properties, and surface modification for the preparation of homogeneous nano composites, generally by sol-gel technique. The effect of nano silica on the properties of various types of silica-polymer composites is also summarized.

Estimating saturated hydraulic conductivity and air permeability from soil physical properties using state-space analysis

DEFF Research Database (Denmark)

Poulsen, Tjalfe; Møldrup, Per; Nielsen, Don

2003-01-01

and gaseous chemicals in the vadose zone. In this study, three modeling approaches were used to identify the dependence of saturated hydraulic conductivity (K-S) and air permeability at -100 cm H2O soil-water potential (k(a100)) on soil physical properties in undisturbed soil: (i) Multiple regression, (ii......) ARIMA (autoregressive integrated moving average) modeling, and (iii) State-space modeling. In addition to actual soil property values, ARIMA and state-space models account for effects of spatial correlation in soil properties. Measured data along two 70-m-long transects at a 20-year old constructed......Estimates of soil hydraulic conductivity (K) and air permeability (k(a)) at given soil-water potentials are often used as reference points in constitutive models for K and k(a) as functions of moisture content and are, therefore, a prerequisite for predicting migration of water, air, and dissolved...

Physical Properties of Low-Molecular Weight Polydimethylsiloxane Fluids

Energy Technology Data Exchange (ETDEWEB)

Roberts, Christine Cardinal [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Graham, Alan [Univ. of Colorado, Denver, CO (United States); Nemer, Martin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Phinney, Leslie M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Garcia, Robert M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Soehnel, Melissa Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stirrup, Emily Kate [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-02-01

Physical property measurements including viscosity, density, thermal conductivity, and heat capacity of low-molecular weight polydimethylsiloxane (PDMS) fluids were measured over a wide temperature range (-50°C to 150°C when possible). Properties of blends of 1 cSt and 20 cSt PDMS fluids were also investigated. Uncertainties in the measurements are cited. These measurements will provide greater fidelity predictions of environmental sensing device behavior in hot and cold environments.

Modeling the temperature dependence of thermophysical properties: Study on the effect of temperature dependence for RFA.

Science.gov (United States)

Watanabe, Hiroki; Kobayashi, Yo; Hashizume, Makoto; Fujie, Masakatsu G

2009-01-01

Radio frequency ablation (RFA) has increasingly been used over the past few years and RFA treatment is minimally invasive for patients. However, it is difficult for operators to control the precise formation of coagulation zones due to inadequate imaging modalities. With this in mind, an ablation system using numerical simulation to analyze the temperature distribution of the organ is needed to overcome this deficiency. The objective of our work is to develop a temperature dependent thermophysical liver model. First, an overview is given of the development of the thermophysical liver model. Second, a simulation to evaluate the effect of temperature dependence of the thermophysical properties of the liver is explained. Finally, the result of the simulation, which indicated that the temperature dependence of thermophysical properties accounts for temperature differences influencing the accuracy of RFA treatment is described.

Physical and elastic properties of marine sediments off Bombay, India

Digital Repository Service at National Institute of Oceanography (India)

SubbaRaju, L.V.; Ramana, Y.V.

45'N and 21 degrees 00N. Representative core samples preserving their natural state were also retrieved from the region in the water depths ranging from 5 to 70 m for the determination of physical properties in the laboratory. Data on the physical...

Exploration of mechanisms underlying the strain-rate-dependent mechanical property of single chondrocytes

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Trung Dung; Gu, YuanTong, E-mail: yuantong.gu@qut.edu.au [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland (Australia)

2014-05-05

Based on the characterization by Atomic Force Microscopy, we report that the mechanical property of single chondrocytes has dependency on the strain-rates. By comparing the mechanical deformation responses and the Young's moduli of living and fixed chondrocytes at four different strain-rates, we explore the deformation mechanisms underlying this dependency property. We found that the strain-rate-dependent mechanical property of living cells is governed by both of the cellular cytoskeleton and the intracellular fluid when the fixed chondrocytes are mainly governed by their intracellular fluid, which is called the consolidation-dependent deformation behavior. Finally, we report that the porohyperelastic constitutive material model which can capture the consolidation-dependent behavior of both living and fixed chondrocytes is a potential candidature to study living cell biomechanics.

Use of ultrasound to monitor physical properties of soybean oil

Science.gov (United States)

Baêsso, R. M.; Oliveira, P. A.; Morais, G. C.; Alvarenga, A. V.; Costa-Félix, R. P. B.

2016-07-01

The study of the monitoring physical properties of soybean oil was performed. The pulse-echo method allowed measuring the density and viscosity of the oil in real time and accurately. The physical property values were related to the acoustic time of flight ratio, dimensionless parameter that can be obtained from any reference. In our case, we used the time of flight at 20°C as reference and a fixed distance between the transducer and the reflector. Ultrasonic monitoring technique employed here has shown promising in the analysis of edible oils.

Processing-structure-property relationships in electron beam physical vapor deposited yttria stabilized zirconia coatings

International Nuclear Information System (INIS)

Rao, D. Srinivasa; Valleti, Krishna; Joshi, S. V.; Janardhan, G. Ranga

2011-01-01

The physical and mechanical properties of yttria stabilized zirconia (YSZ) coatings deposited by the electron beam physical vapor deposition technique have been investigated by varying the key process variables such as vapor incidence angle and sample rotation speed. The tetragonal zirconia coatings formed under varying process conditions employed were found to have widely different surface and cross-sectional morphologies. The porosity, phase composition, planar orientation, hardness, adhesion, and surface residual stresses in the coated specimens were comprehensively evaluated to develop a correlation with the process variables. Under transverse scratch test conditions, the YSZ coatings exhibited two different crack formation modes, depending on the magnitude of residual stress. The influence of processing conditions on the coating deposition rate, column orientation angle, and adhesion strength has been established. Key relationships between porosity, hardness, and adhesion are also presented.

Effect of barium doping on the physical properties of zinc oxide ...

Indian Academy of Sciences (India)

2015-11-27

Home; Journals; Pramana – Journal of Physics; Volume 87; Issue 1. Effect of barium doping on the physical properties of zinc oxide ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November 27, 2015. Guest Editors: ...

Estimation of Physical Properties of AN-107 Cesium and Technetium Eluate Blend

Energy Technology Data Exchange (ETDEWEB)

Choi, A.S.

2001-06-12

The objective of this study, as defined in the associated test specifications and task technical and quality assurance plan, was to estimate all the physical properties that are required to design the storage and transport facilities for the concentrated cesium and technetium eluates. Specifically, the scope of this study included: (1) modeling of the aqueous electrolyte chemistry of Tank 241-AN-107 Cs and Tc eluate evaporators, (2) process modeling of semi-batch and continuous evaporation operations, (3) determination of the operating vacuum and target endpoint of each evaporator, (4) calculation of the physical properties of the concentrated Cs and Tc eluate blend, and (5) development of the empirical correlations for the physical properties thus estimated.

Physical Properties of Hanford Transuranic Waste. Final Report

International Nuclear Information System (INIS)

Berg, John C.

2010-01-01

The research described herein was undertaken to provide needed physical property descriptions of the Hanford transuranic tank sludges under conditions that might exist during retrieval, treatment, packaging and transportation for disposal. The work addressed the development of a fundamental understanding of the types of systems represented by these sludge suspensions through correlation of the macroscopic rheological properties with particle interactions occurring at the colloidal scale in the various liquid media. The results of the work have advanced existing understanding of the sedimentation and aggregation properties of complex colloidal suspensions. Bench scale models were investigated with respect to their structural, colloidal and rheological properties that should be useful for the development and optimization of techniques to process the wastes at various DOE sites.

Influence of wheat kernel physical properties on the pulverizing process.

Science.gov (United States)

Dziki, Dariusz; Cacak-Pietrzak, Grażyna; Miś, Antoni; Jończyk, Krzysztof; Gawlik-Dziki, Urszula

2014-10-01

The physical properties of wheat kernel were determined and related to pulverizing performance by correlation analysis. Nineteen samples of wheat cultivars about similar level of protein content (11.2-12.8 % w.b.) and obtained from organic farming system were used for analysis. The kernel (moisture content 10 % w.b.) was pulverized by using the laboratory hammer mill equipped with round holes 1.0 mm screen. The specific grinding energy ranged from 120 kJkg(-1) to 159 kJkg(-1). On the basis of data obtained many of significant correlations (p kernel physical properties and pulverizing process of wheat kernel, especially wheat kernel hardness index (obtained on the basis of Single Kernel Characterization System) and vitreousness significantly and positively correlated with the grinding energy indices and the mass fraction of coarse particles (> 0.5 mm). Among the kernel mechanical properties determined on the basis of uniaxial compression test only the rapture force was correlated with the impact grinding results. The results showed also positive and significant relationships between kernel ash content and grinding energy requirements. On the basis of wheat physical properties the multiple linear regression was proposed for predicting the average particle size of pulverized kernel.

Selected physical properties of various diesel blends

Science.gov (United States)

Hlaváčová, Zuzana; Božiková, Monika; Hlaváč, Peter; Regrut, Tomáš; Ardonová, Veronika

2018-01-01

The quality determination of biofuels requires identifying the chemical and physical parameters. The key physical parameters are rheological, thermal and electrical properties. In our study, we investigated samples of diesel blends with rape-seed methyl esters content in the range from 3 to 100%. In these, we measured basic thermophysical properties, including thermal conductivity and thermal diffusivity, using two different transient methods - the hot-wire method and the dynamic plane source. Every thermophysical parameter was measured 100 times using both methods for all samples. Dynamic viscosity was measured during the heating process under the temperature range 20-80°C. A digital rotational viscometer (Brookfield DV 2T) was used for dynamic viscosity detection. Electrical conductivity was measured using digital conductivity meter (Model 1152) in a temperature range from -5 to 30°C. The highest values of thermal parameters were reached in the diesel sample with the highest biofuel content. The dynamic viscosity of samples increased with higher concentration of bio-component rapeseed methyl esters. The electrical conductivity of blends also increased with rapeseed methyl esters content.

The effect of mixing order of fillers on the physical properties of EPDM

International Nuclear Information System (INIS)

Gul, J.; Saleemi, A.R.

2007-01-01

In this research the effect of mixing order of fillers on the physical properties of EPDM (Ethylene Propylene Diene Monomer) vulcanizates was studied. EPDM was compounded with other ingredients i.e. fillers, process aid, curing package etc in order to get the needed physical properties for thermal insulation. All the factors, which could affect the physical properties of EPDM vulcanizates such as quality and quantity of raw materials, storage conditions of ingredients and vulcanizates, compounding and testing facilities, mixing time, process parameters etc were kept constant except mixing order of addition of filler to EPDM. Different batches of EPDM vulcanizates with different mixing order/sequence of filler to EPDM were prepared and tested for physical properties like density, hardness, tensile strength and elongation. It was concluded that mixing order of filler to EPDM affects tensile strength, elongation and hardness and does not affect density of the EPDM vulcanizate. (author)

Preparation and characterization of nano fluids: Influence of variables on its stability, agglomeration state and physical properties

International Nuclear Information System (INIS)

Mondragon, R.; Julia, J. E.; Barba, A.; Jarque, J. C.

2014-01-01

In recent years it has spread the use of suspensions containing nano metre sized particles, known as nano fluids, in many applications owing the good properties having nanocrystalline materials. One of the main advantages of using nano fluids is its high stability, which causes the particles do not settle over long periods of time. This stability depends on the preparation conditions such as pH, the presence of electrolytes or the solids content. Moreover, there are a number of physical properties which are influenced and altered by agglomeration of the particles. This article will analyze all the variables that affect agglomeration of the particles, nano fluids stability and properties from which it can obtain information on the state of suspension. It then lays out the different methods of dispersion of nanoparticles and their effectiveness. (Author)

Effects of gamma irradiation on the physical and structural properties of β-glucan

International Nuclear Information System (INIS)

Byun, Eui-Hong; Kim, Jae-Hun; Sung, Nak-Yun; Choi, Jong-il; Lim, Seong-Taek; Kim, Kwang-Hoon; Yook, Hong-Sun; Byun, Myung-Woo; Lee, Ju-Woon

2008-01-01

This study was carried out to evaluate the effect of gamma irradiation on the physical and structural properties of β-glucan. β-Glucan solution (10%, w/v) was exposed to a cobalt-60 source (10, 30, and 50 kGy). Gel permeation chromatography data showed that the average molecular weight of irradiated β-glucan significantly decreased as the irradiation dose increased. In addition, gamma irradiation improved the solubility and decreased the viscosity of β-glucan by the radiolysis of the glycosidic bonds, and this effect was dependent upon the absorbed dose. Fourier transform infrared spectroscopy results showed that the functional groups of β-glucan were not significantly affected by gamma irradiation. Scanning electron microscopy results showed that the irradiated β-glucan was deformed into smaller granules. Therefore, gamma irradiation could be used in commercial processes as an effective method to resolve the physical problems involved in the use of β-glucan with high viscosity and low solubility

Ultrasonic evaluation of the physical and mechanical properties of granites.

Science.gov (United States)

Vasconcelos, G; Lourenço, P B; Alves, C A S; Pamplona, J

2008-09-01

Masonry is the oldest building material that survived until today, being used all over the world and being present in the most impressive historical structures as an evidence of spirit of enterprise of ancient cultures. Conservation, rehabilitation and strengthening of the built heritage and protection of human lives are clear demands of modern societies. In this process, the use of nondestructive methods has become much common in the diagnosis of structural integrity of masonry elements. With respect to the evaluation of the stone condition, the ultrasonic pulse velocity is a simple and economical tool. Thus, the central issue of the present paper concerns the evaluation of the suitability of the ultrasonic pulse velocity method for describing the mechanical and physical properties of granites (range size between 0.1-4.0 mm and 0.3-16.5 mm) and for the assessment of its weathering state. The mechanical properties encompass the compressive and tensile strength and modulus of elasticity, and the physical properties include the density and porosity. For this purpose, measurements of the longitudinal ultrasonic pulse velocity with distinct natural frequency of the transducers were carried out on specimens with different size and shape. A discussion of the factors that induce variations on the ultrasonic velocity is also provided. Additionally, statistical correlations between ultrasonic pulse velocity and mechanical and physical properties of granites are presented and discussed. The major output of the work is the confirmation that ultrasonic pulse velocity can be effectively used as a simple and economical nondestructive method for a preliminary prediction of mechanical and physical properties, as well as a tool for the assessment of the weathering changes of granites that occur during the serviceable life. This is of much interest due to the usual difficulties in removing specimens for mechanical characterization.

Effect of temperature on the morphology and electro-optical properties of liquid crystal physical gel

International Nuclear Information System (INIS)

Leaw, W.L.; Mamat, C.R.; Triwahyono, S.; Jalil, A.A.; Bidin, N.

2016-01-01

Liquid crystal physical gels were (thermally) prepared with cholesteryl stearate as a gelator in nematic liquid crystal, 4-cyano-4′-pentylbiphenyl. The electro-optical performance of liquid crystal physical gels is almost entirely dependent on the gels' inherent morphology. This study involved an empirical investigation of the relationships among all of the gelation temperature, morphology, and electro-optical properties. Besides continuous cooling at room temperature, isothermal cooling was also performed at both 18 and 0 °C, corresponding to near-solid and solid phases of 4-cyano-4′-pentylbiphenyl respectively. Nevertheless, the liquid crystal physical gel was also isothermally rapidly cooled using liquid nitrogen. Polarizing optical microscopy showed that the gel structure became thinner when isothermal cooling was carried out. These thinner gel aggregates then interconnected to form larger liquid crystal domains. Moreover, it was also revealed that the gel networks were randomized. Electron spin resonance results showed that the liquid crystal director orientation was severely randomized in the presence of gel networks. Conversely, isothermal cooling using liquid nitrogen generated a higher liquid crystal director orientation order. The 6.0 wt% cholesteryl stearate/4-cyano-4′-pentylbiphenyl physical gel that was isothermally cooled using liquid nitrogen showed the lowest response time in a twisted nematic mode optical cell. - Graphical abstract: Liquid crystal physical gel was prepared using nematic liquid crystal, 4-cyano-4′-pentylbiphenyl and cholesteryl stearate as gelator. Isothermal cooling at lower temperature produced thinner gel network and larger liquid crystal domain. - Highlights: • 5CB nematic liquid crystal was successfully gelled by cholesteryl stearate gelator. • The morphology of gel network was controlled by different cooling conditions. • Thinner gel network was formed by the rapid cooling using liquid nitrogen. • Enhanced

Effect of temperature on the morphology and electro-optical properties of liquid crystal physical gel

Energy Technology Data Exchange (ETDEWEB)

Leaw, W.L. [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Mamat, C.R., E-mail: che@kimia.fs.utm.my [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Triwahyono, S. [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Jalil, A.A. [Department of Chemical Engineering, Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Centre of Hydrogen Energy, Institute of Future Energy, Univerisiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia); Bidin, N. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310, UTM Johor Bahru, Johor (Malaysia)

2016-12-01

Liquid crystal physical gels were (thermally) prepared with cholesteryl stearate as a gelator in nematic liquid crystal, 4-cyano-4′-pentylbiphenyl. The electro-optical performance of liquid crystal physical gels is almost entirely dependent on the gels' inherent morphology. This study involved an empirical investigation of the relationships among all of the gelation temperature, morphology, and electro-optical properties. Besides continuous cooling at room temperature, isothermal cooling was also performed at both 18 and 0 °C, corresponding to near-solid and solid phases of 4-cyano-4′-pentylbiphenyl respectively. Nevertheless, the liquid crystal physical gel was also isothermally rapidly cooled using liquid nitrogen. Polarizing optical microscopy showed that the gel structure became thinner when isothermal cooling was carried out. These thinner gel aggregates then interconnected to form larger liquid crystal domains. Moreover, it was also revealed that the gel networks were randomized. Electron spin resonance results showed that the liquid crystal director orientation was severely randomized in the presence of gel networks. Conversely, isothermal cooling using liquid nitrogen generated a higher liquid crystal director orientation order. The 6.0 wt% cholesteryl stearate/4-cyano-4′-pentylbiphenyl physical gel that was isothermally cooled using liquid nitrogen showed the lowest response time in a twisted nematic mode optical cell. - Graphical abstract: Liquid crystal physical gel was prepared using nematic liquid crystal, 4-cyano-4′-pentylbiphenyl and cholesteryl stearate as gelator. Isothermal cooling at lower temperature produced thinner gel network and larger liquid crystal domain. - Highlights: • 5CB nematic liquid crystal was successfully gelled by cholesteryl stearate gelator. • The morphology of gel network was controlled by different cooling conditions. • Thinner gel network was formed by the rapid cooling using liquid nitrogen. �

Influence of aluminium content on the physical, mechanical and sliding wear properties of zinc-based alloys

International Nuclear Information System (INIS)

Prasad, B.K.; Patwardhan, A.K.; Yegneswaran, A.H.

1997-01-01

Attention has been focussed on the influence of Al content on the physical, mechanical and sliding wear properties of Zn-based alloys. Aspects studied include microstructure, density, electrical conductivity, hardness, tensile strength and elongation as well as sliding wear response of the alloys. Microstructural features of the alloys showed the presence of primary α, eutectic/eutectoid α + η (depending on whether the alloy was hypereutectic/hypereutectoid with regard to the concentration of Al) along with the meta stable ε phase. The study suggests that it is possible to design and develop Zn-based alloys with a wide range of concentration of Al. The alloys in turn attain different combinations of physical, mechanical and wear properties which could suit a variety of engineering applications. Increasing the Al content in the alloy system proves beneficial within limits. In other words, there exists an optimum quantity of Al which could reap its advantage to the maximum extent. This of course varies with reference to a specific property of the alloy(s). The changing response of the alloys has been explained in terms of their microstructural features and the effects produced as a result of the test conditions maintained while characterizing the specimens. (orig.)

Frequency-Dependent Properties of Magnetic Nanoparticle Crystals

Energy Technology Data Exchange (ETDEWEB)

Majetich, Sara [Carnegie Mellon Univ., Pittsburgh, PA (United States)

2016-05-17

In the proposed research program we will investigate the time- and frequency-dependent behavior of ordered nanoparticle assemblies, or nanoparticle crystals. Magnetostatic interactions are long-range and anisotropic, and this leads to complex behavior in nanoparticle assemblies, particularly in the time- and frequency-dependent properties. We hypothesize that the high frequency performance of composite materials has been limited because of the range of relaxation times; if a composite is a dipolar ferromagnet at a particular frequency, it should have the advantages of a single phase material, but without significant eddy current power losses. Arrays of surfactant-coated monodomain magnetic nanoparticles can exhibit long-range magnetic order that is stable over time. The magnetic domain size and location of domain walls is governed not by structural grain boundaries but by the shape of the array, due to the local interaction field. Pores or gaps within an assembly pin domain walls and limit the domain size. Measurements of the magnetic order parameter as a function of temperature showed that domains can exist at high temoerature, and that there is a collective phase transition, just as in an exchange-coupled ferromagnet. Dipolar ferromagnets are not merely of fundamental interest; they provide an interesting alternative to exchange-based ferromagnets. Dipolar ferromagnets made with high moment metallic particles in an insulating matrix could have high permeability without large eddy current losses. Such nanocomposites could someday replace the ferrites now used in phase shifters, isolators, circulators, and filters in microwave communications and radar applications. We will investigate the time- and frequency-dependent behavior of nanoparticle crystals with different magnetic core sizes and different interparticle barrier resistances, and will measure the magnetic and electrical properties in the DC, low frequency (0.1 Hz - 1 kHz), moderate frequency (10 Hz - 500

Tailoring the physical properties of manganite thin films by tuning the epitaxial strain

International Nuclear Information System (INIS)

Zhang, P.X.; Zhang, H.; Cha, L.M.; Habermeier, H.-U.

2003-01-01

Through a proper choice of the mismatch between substrate and films, the physical properties of manganite thin films can be tailored We show that two types of manganite thin films of the Ruddlesden-Popper family, n=∞ and n=2, demonstrate a dramatic variation of their physical properties. It is proved that the property variation can be tuned precisely by controlling the lattice mismatch and/or the film thickness

Chirality: a relational geometric-physical property.

Science.gov (United States)

Gerlach, Hans

2013-11-01

The definition of the term chirality by Lord Kelvin in 1893 and 1904 is analyzed by taking crystallography at that time into account. This shows clearly that chirality is a relational geometric-physical property, i.e., two relations between isometric objects are possible: homochiral or heterochiral. In scientific articles the relational term chirality is often mistaken for the two valued measure for the individual (absolute) sense of chirality, an arbitrary attributive term. © 2013 Wiley Periodicals, Inc.

Nanoemulsions: formation, structure, and physical properties

International Nuclear Information System (INIS)

Mason, T G; Wilking, J N; Meleson, K; Chang, C B; Graves, S M

2006-01-01

We summarize procedures for producing 'nanoemulsions' comprised of nanoscale droplets, or 'nanoemulsions', methods for controlling the droplet size distribution and composition, and interesting physical properties of nanoemulsions. In contrast to more common microscale emulsions, nanoemulsions exhibit optical transparency at high droplet volume fractions, φ, surprisingly strong elasticity at low φ, and enhanced diffusive transport and shelf stability. For these reasons, nanoemulsions have great potential in a wide range of industries including pharmaceuticals, foods, and personal care products. (topical review)

Comments on Thermal Physical Properties Testing Methods of Phase Change Materials

Directory of Open Access Journals (Sweden)

Jingchao Xie

2013-01-01

Full Text Available There is no standard testing method of the thermal physical properties of phase change materials (PCM. This paper has shown advancements in this field. Developments and achievements in thermal physical properties testing methods of PCM were commented, including differential scanning calorimetry, T-history measurement, the water bath method, and differential thermal analysis. Testing principles, advantages and disadvantages, and important points for attention of each method were discussed. A foundation for standardized testing methods for PCM was made.

Chemistry and physical properties of estolides

International Nuclear Information System (INIS)

Isbell, T.A.

2011-01-01

Estolides are a developing class of natural and synthetic compounds that have been synthesized from hydroxy oils like castor and lesquerella or by the condensation of fatty acids across the olefin of a second fatty acid. Castor and lesquerella estolides are derived from either their triglycerides or their free fatty acids utilizing their hydroxyl moiety to establish the estolide bond. The triglyceride estolides have pour points of 9 to -36 degrees centigrade but suffer poor oxidative stability with RPVOT times of 29 - 52 minutes even with 1% of an anti-oxidant package incorporated into the samples. In contrast to the triglyceride estolides of castor and lesquerella, the estolides from lesquerolic and ricinoleic acids have very good pour points of -36 to - 54 degrees centigrade. Estolides derived from the acid catalyzed condensation of oleic acid with a variety of fatty acids can be made in good yield and posses a wide range of physical properties. Of particular interest are the saturated capped estolides of oleic that have both good low temperature properties (pour point -5 to -39 degrees centigrade) and good oxidative stability. Estolides from meadow foam fatty acids do not have good low temperature properties but have been extensively used in cosmetics where they provide good moisturizing properties. (Author).

Impact of UV radiation on the physical properties of polypropylene ...

African Journals Online (AJOL)

The purpose of this study was to analyse the influence of simulated sun light radiation (xenon lamp) on physical properties of polypropylene (PP) nonwoven material, which is used for the production of agrotextiles. The research showed that the properties of row cover change when radiated with UV light. Tensile, tearing ...

Influence of physical properties and operating parameters on hydrodynamics in Centrifugal Partition Chromatography.

Science.gov (United States)

Adelmann, S; Schembecker, G

2011-08-12

Besides the selection of a suitable biphasic solvent system the separation efficiency in Centrifugal Partition Chromatography (CPC) is mainly influenced by the hydrodynamics in the chambers. The flow pattern, the stationary phase retention and the interfacial area for mass transfer strongly depend on physical properties of the solvent system and operating parameters. In order to measure these parameters we visualized the hydrodynamics in a FCPC-chamber for five different solvent systems with an optical measurement system and calculated the stationary phase retention, interfacial area and the distribution of mobile phase thickness in the chamber. Although inclined chambers were used we found that the Coriolis force always deflected the mobile phase towards the chamber wall reducing the interfacial area. This effect increased for systems with low density difference. We also have shown that the stability of phase systems (stationary phase retention) and its tendency to disperse increased for smaller values of the ratio of interfacial tension and density difference. But also the viscosity ratio and the flow pattern itself had a significant effect on retention and dispersion of the mobile phase. As a result operating parameters should be chosen carefully with respect to physical properties for a CPC system. In order to reduce the effect of the Coriolis force CPC devices with greater rotor radius are desirable. Copyright © 2011 Elsevier B.V. All rights reserved.

Avian magnetic compass: Its functional properties and physical basis

Directory of Open Access Journals (Sweden)

Roswitha WILTSCHKO, Wolfgang WILTSCHKO

2010-06-01

Full Text Available The avian magnetic compass was analyzed in bird species of three different orders – Passeriforms, Columbiforms and Galliforms – and in three different behavioral contexts, namely migratory orientation, homing and directional conditioning. The respective findings indicate similar functional properties: it is an inclination compass that works only within a functional window around the ambient magnetic field intensity; it tends to be lateralized in favor of the right eye, and it is wavelength-dependent, requiring light from the short-wavelength range of the spectrum. The underlying physical mechanisms have been identified as radical pair processes, spin-chemical reactions in specialized photopigments. The iron-based receptors in the upper beak do not seem to be involved. The existence of the same type of magnetic compass in only very distantly related bird species suggests that it may have been present already in the common ancestors of all modern birds, where it evolved as an all-purpose compass mechanism for orientation within the home range [Current Zoology 56 (3: 265–276, 2010].

Influence of physical properties of soil on 137 Cs mobility

International Nuclear Information System (INIS)

Kanapickas, A.; Paulaitiene, I.; Mazeika, J.; Bauziene, I.

2005-01-01

A model to account for the mobility of radiocesium in soil is presented. The model requires a minimal set of coefficients that describe radiocesium migration and fixation rates, which can be related to physical soil properties. The peculiarities of experimental radiocesium profiles in soil are explained by the composition of soil, which affects the radiocesium fixation rate. It is shown that the migration of radiocesium in soil is governed by vertical convection of a mobile form, whereas diffusion is a slower process due to strong fixation. The results show that the velocity of vertical migration downward of mobile radiocesium can be set constant, because the overall migration rate depends on fixation. Modeling of experimental radiocesium soil profiles suggests that organic (humic) layers with reduced mineral content and humidity have a high radiocesium fixation rate. Soil structure that maintains high soil humidity and mineral content has an increased cesium exchangeability and. consequently, higher radiocesium mobility. (author)

Physical Properties of Aten, Apollo and Amor asteroids

International Nuclear Information System (INIS)

McFadden, L.A.; Tholen, D.J.; Veeder, G.J.

1989-01-01

The physical properties of Aten, Apollo and Amor objects includeing their taxonomy, composition, size, rotation rate, shape and surface texture, are derived from observations using spectrophometry, reflectance spectroscopy, broadband photometry, radiometry, polarimetry and radar. The authors discuss how their current understanding of this population is that it is diverse in terms of all physical properties that can be studied from the ground and consists of contributions from more than one source region. Almost all taxonomic types found in the main belt are present amoung this population. Class Q objects are unique to the AAAO population. Both low-temperature assemblages, which are dark and probably carbonaceous-rich, and high-temperature, differentiated assemblages of olivine, pyroxene and metallic phases, are found amoung the AAAO. These asteroids have experienced a range of different thermal regimes in the past. Discovery biases probably create the high abundance of bright objects. A bimodal distribution of rotation rates indicates that the population is not collisionally evolved

Novel Dilute Bismide, Epitaxy, Physical Properties and Device Application

Directory of Open Access Journals (Sweden)

Lijuan Wang

2017-02-01

Full Text Available Dilute bismide in which a small amount of bismuth is incorporated to host III-Vs is the least studied III-V compound semiconductor and has received steadily increasing attention since 2000. In this paper, we review theoretical predictions of physical properties of bismide alloys, epitaxial growth of bismide thin films and nanostructures, surface, structural, electric, transport and optic properties of various binaries and bismide alloys, and device applications.

Regime-dependent topological properties of biofuels networks

Czech Academy of Sciences Publication Activity Database

Krištoufek, Ladislav; Janda, K.; Zilberman, D.

2013-01-01

Roč. 86, č. 2 (2013), 40-1-40-12 ISSN 1434-6028 R&D Projects: GA ČR GA402/09/0965 Grant - others:GA UK(CZ) 118310; GA ČR(CZ) GAP402/11/0948 Program:GA Institutional support: RVO:67985556 Keywords : topology * biofuels * correlations Subject RIV: AH - Economics Impact factor: 1.463, year: 2013 http://library.utia.cas.cz/separaty/2013/E/kristoufek-regime-dependent topological properties of biofuels networks.pdf

Self-reported cue-induced physical symptoms of craving as an indicator of cocaine dependence.

Science.gov (United States)

Vorspan, Florence; Fortias, Maeva; Zerdazi, El-Hadi; Karsinti, Emily; Bloch, Vanessa; Lépine, Jean-Pierre; Bellivier, Frank; Brousse, Georges; van den Brink, Wim; Derks, Eske M

2015-12-01

The presence of cocaine dependence is under-recognized by cocaine users and requires a careful standardized interview to be ascertained by clinicians. To test if past experiences of cue-induced physical symptoms of craving (nausea, vomiting, sweating, shaking, nervousness) before cocaine use could be a useful way to boost the diagnosis of cocaine dependence. A cross-sectional study of 221 cocaine users from several outpatient addiction treatment services in France, addressing the most severe period of cocaine use. DSM-IV cocaine dependence was determined with the MINI International Neuropsychiatric Interview (MINI). Physical symptoms before using cocaine were retrospectively assessed with a single item rated on a 0-5 scale. The prevalence of DSM-IV cocaine dependence was 84.6%. The mean score on the physical symptoms item was 1.3 (SD 1.3). A cut-off score of ≥ 1 on this item alone resulted in a sensitivity of 62%, a specificity of 88.2%, a positive predictive value of 96.6% and a negative predictive value of 29.7% to detect DSM IV cocaine dependence in this sample. Adding this item to a model with the frequency of cocaine use significantly increased the predictive power: Nagelkerke's R(2) increased from .149 to .326 (p physical signs of cocaine craving is associated with a clinical diagnosis of lifetime cocaine dependence and could be a simple way to improve its detection in clinical settings. © American Academy of Addiction Psychiatry.

Sex-dependent differences in voluntary physical activity.

Science.gov (United States)

Rosenfeld, Cheryl S

2017-01-02

Numbers of overweight and obese individuals are increasing in the United States and globally, and, correspondingly, the associated health care costs are rising dramatically. More than one-third of children are currently considered obese with a predisposition to type 2 diabetes, and it is likely that their metabolic conditions will worsen with age. Physical inactivity has also risen to be the leading cause of many chronic, noncommunicable diseases (NCD). Children are more physically inactive now than they were in past decades, which may be due to intrinsic and extrinsic factors. In rodents, the amount of time engaged in spontaneous activity within the home cage is a strong predictor of later adiposity and weight gain. Thus, it is important to understand primary motivators stimulating physical activity (PA). There are normal sex differences in PA levels in rodents and humans. The perinatal environment can induce sex-dependent differences in PA disturbances. This Review considers the current evidence for sex differences in PA in rodents and humans. The rodent studies showing that early exposure to environmental chemicals can shape later adult PA responses are discussed. Next, whether there are different motivators stimulating exercise in male vs. female humans are examined. Finally, the brain regions, genes, and pathways that modulate PA in rodents, and possibly by translation in humans, are described. A better understanding of why each sex remains physically active through the life span could open new avenues for preventing and treating obesity in children and adults. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Physical, mechanical, and fire properties of oriented strandboard with fire retardant treated veneers

Science.gov (United States)

Nadir Ayrilmis; Zeki Candan; Robert White

2007-01-01

This study evaluated physical, mechanical and fire properties of oriented strand boards (OSB) covered with fire retardant treated veneers. The beech (Fagus orientalis Lipsky) veneers were treated with either monoammonium phosphate, diammonium phosphate, lime water or a borax/boric acid (1 : 1 by weight) mixture. Physical and mechanical properties of the specimens were...

The physical fibre properties of Gonometa postica after degumming

African Journals Online (AJOL)

user

The physical fibre properties of Gonometa postica after degumming the ... chemical Orvus paste as degumming method ..... technological applications, it is an important .... The development of an effective ... Engineering, 54(6), 179-190. Das, S.

Study of Time-Dependent Properties of Thermoplastics

Directory of Open Access Journals (Sweden)

Bolchoun A.

2010-06-01

Full Text Available Simple tests carried out with a common tension/compression testing machine are used to obtain timedependent properties of non-reinforced thermoplastics. These tests include ramp loadings as well as relaxation and creep tests. Two materials (PBT Celanex 2002-2 and POM Hostaform C9021, Ticona GmbH, Kelsterbach were taken for the experiments. The experiments show that an adequate description of the long-term material properties can be obtained from the short-time tests, namely from tests with constant traverse speed $L^.$. Below a model for the time-dependent mechanical behavior is presented and fitted to the obtained measured data. For the evaluation of the fitting quality long-term tests are used. Especially creep and relaxation tests with ”jumps”, i.e. rapid change of loading, are important for this purpose.

The physical properties of Lyα emitting galaxies: not just primeval galaxies?

Science.gov (United States)

Pentericci, L.; Grazian, A.; Fontana, A.; Castellano, M.; Giallongo, E.; Salimbeni, S.; Santini, P.

2009-02-01

Aims: We have analyzed a sample of Lyman break galaxies from z ~ 3.5 to z ~ 6 selected from the GOODS-S field as B, V, and i-dropouts, and with spectroscopic observations showing that they have the Lyα line in emission. Our main aim is to investigate their physical properties and their dependence on the emission line characteristic and to shed light on the relation between galaxies with Lyα emission and the general LBG population. Methods: The objects were selected from their optical continuum colors and then spectroscopically confirmed by the GOODS collaboration and other campaigns. From the public spectra we derived the main properties of the Lyα emission such as total flux and rest frame EW. We then used complete photometry, from U band to mid-infrared from the GOODS-MUSIC database, and through standard spectro-photometric techniques we derived the physical properties of the galaxies, such as total stellar mass, stellar ages, star formation rates, and dust content. Finally we investigated the relation between emission line and physical properties. Results: Although most galaxies are fit by young stellar populations, a small but non negligible fraction has SEDs that cannot be represented well by young models and require considerably older stellar component, up to ~1 Gyr. There is no apparent relation between age and EW: some of the oldest galaxies have high line EW, and should be also selected in narrow-band surveys. Therefore not all Lyα emitting galaxies are primeval galaxies in the very early stages of formation, as is commonly assumed. We also find a range of stellar populations, with masses from 5 × 108 M_⊙ to 5 × 1010 M_⊙ and SFR from few to 60 M_⊙ yr-1. Although there is no net correlation between mass and EW, we find a significant lack of massive galaxies with high EW, which could be explained if the most massive galaxies were either dustier and/or if they contained more neutral gas than less massive objects. Finally we find that more than

Thermal behavior and mechanical properties of physically crosslinked PVA/Gelatin hydrogels.

Science.gov (United States)

Liu, Yurong; Geever, Luke M; Kennedy, James E; Higginbotham, Clement L; Cahill, Paul A; McGuinness, Garrett B

2010-02-01

Poly (vinyl alcohol)/Gelatin hydrogels are under active investigation as potential vascular cell culture biomaterials, tissue models and vascular implants. The PVA/Gelatin hydrogels are physically crosslinked by the freeze-thaw technique, which is followed by a coagulation bath treatment. In this study, the thermal behavior of the gels was examined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). Rheological measurement and uniaxial tensile tests revealed key mechanical properties. The role of polymer fraction in relation to these mechanical properties is explored. Gelatin has no significant effect on the thermal behavior of PVA, which indicates that no substantial change occurs in the PVA crystallite due to the presence of gelatin. The glass transition temperature, melting temperature, degree of crystallinity, polymer fraction, storage modulus (G') and ultimate strength of one freeze-thaw cycle (1FT) hydrogels are inferior to those of 3FT hydrogels. With coagulation, both 1FT and 3FT hydrogels shifted to a lower value of T(g), melting temperature and polymer fraction are further increased and the degree of crystallinity is depressed. The mechanical properties of 1FT, but not 3FT, were strengthened with coagulation treatment. This study gives a detailed investigation of the microstructure formation of PVA/Gelatin hydrogel in each stage of physical treatments which helps us to explain the role of physical treatments in tuning their physical properties for biomechanical applications. Copyright 2009 Elsevier Ltd. All rights reserved.

Effect of hydrogen on Fe and Pd alloying and physical properties

Czech Academy of Sciences Publication Activity Database

Jirásková, Yvonna; Buršík, Jiří; Zemanová, Adéla; Čízek, J.; Hruška, P.; Životský, O.

2017-01-01

Roč. 42, č. 10 (2017), s. 6885-6901 ISSN 0360-3199 R&D Projects: GA MŠk(CZ) LQ1601 Institutional support: RVO:68081723 Keywords : positron-lifetime spectroscopy * neutron-diffraction * magnetic-properties * palladium-hydrogen * induced defects * iron Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 3.582, year: 2016

Effects of Music on Image Impression and Relationship between Impression and Physical Properties

Science.gov (United States)

Sato, Keiko; Mitsukura, Yasue

Auditory information plays an integral role in AV media because even identical images are perceived differently when they are matched with different music. However, we now present a few studies in which the changes in subjective perceptions were analyzed on the basis of the physical properties of the perceived items. The purpose of this study is to investigate the effects of music on image impression in terms of the physical properties of images. In this paper, we first elucidate the changes in subjective impressions when the image is presented by itself and when it is presented with music. Secondly, to clarify the relation between the impression of an image or music and physical properties, we compare the different image or music perceptions with each other and also compare their respective physical properties, which include color information, structural information, and frequency characteristics. As a result, the color information of an image containing green or saturation colors and the power of the music were strongly correlated with adjectives expressing activity. Moreover, the entropy of saturation correlated with words expressing spatial extent.

Physical Properties for Lipids Based Process and Product Design

DEFF Research Database (Denmark)

Ana Perederic, Olivia; Kalakul, Sawitree; Sarup, Bent

Lipid processing covers several oil and fats technologies such as: edible oil production, biodieselproduction, oleochemicals (e.g.: food additives, detergents) and pharmaceutical product manufacturing. New demands regarding design and development of better products and more sustainable processes...... related to lipids technology, emerge according to consumers demanding improved product manufacturing from sustainable resources and new legislation regarding environmental safety [1]. Physical and thermodynamic property data and models for prediction of pure compound properties and mixtures properties...... involving lipids represent the basic and most important requirements for process product design, simulation and optimization. Experimentally measured values of involved compounds are desirable, but in most of the cases these are not available for all the compounds and properties needed. The lack...

Retrieval of Macro- and Micro-Physical Properties of Oceanic Hydrosols from Polarimetric Observations

Science.gov (United States)

Ibrahim, Amir; Gilerson, Alexander; Chowdhary, Jacek; Ahmed, Samir

2016-01-01

Remote sensing has mainly relied on measurements of scalar radiance and its spectral and angular features to retrieve micro- and macro-physical properties of aerosols/hydrosols. However, it is recognized that measurements that include the polarimetric characteristics of light provide more intrinsic information about particulate scattering. To take advantage of this, we used vector radiative transfer (VRT) simulations and developed an analytical relationship to retrieve the macro and micro-physical properties of the oceanic hydrosols. Specifically, we investigated the relationship between the observed degree of linear polarization (DoLP) and the ratio of attenuation-to- absorption coefficients (c/a) in water, from which the scattering coefficient can be readily computed (b equals c minus a), after retrieving a. This relationship was parameterized for various scattering geometries, including sensor zenith/azimuth angles relative to the Sun's principal plane, and for varying Sun zenith angles. An inversion method was also developed for the retrieval of the microphysical properties of hydrosols, such as the bulk refractive index and the particle size distribution. The DoLP vs c/a relationship was tested and validated against in-situ measurements of underwater light polarization obtained by a custom-built polarimeter and measurements of the coefficients a and c, obtained using an in-water WET (Western Environmental Technologies) Labs ac-s (attenuation coefficients In-Situ Spectrophotometer) instrument package. These measurements confirmed the validity of the approach, with retrievals of attenuation coefficients showing a high coefficient of determination depending on the wavelength. We also performed a sensitivity analysis of the DoLP at the Top of Atmosphere (TOA) over coastal waters showing the possibility of polarimetric remote sensing application for ocean color.

Using physical properties of molten glass to estimate glass composition

International Nuclear Information System (INIS)

Choi, Kwan Sik; Yang, Kyoung Hwa; Park, Jong Kil

1997-01-01

A vitrification process is under development in KEPRI for the treatment of low-and medium-level radioactive waste. Although the project is for developing and building Vitrification Pilot Plant in Korea, one of KEPRI's concerns is the quality control of the vitrified glass. This paper discusses a methodology for the estimation of glass composition by on-line measurement of molten glass properties, which could be applied to the plant for real-time quality control of the glass product. By remotely measuring viscosity and density of the molten glass, the glass characteristics such as composition can be estimated and eventually controlled. For this purpose, using the database of glass composition vs. physical properties in isothermal three-component system of SiO 2 -Na 2 O-B 2 O 3 , a software TERNARY has been developed which determines the glass composition by using two known physical properties (e.g. density and viscosity)

Size-dependent electronic properties of metal nanostructures

Indian Academy of Sciences (India)

Table of contents. Size-dependent electronic properties of metal nanostructures · Slide 2 · Slide 3 · Slide 4 · Slide 5 · Slide 6 · Slide 7 · Slide 8 · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13 · Slide 14 · Slide 15 · Slide 16 · Slide 17 · Slide 18 · Slide 19 · Nanocrystalline film at liquid-liquid interface · Slide 21 · Slide 22.

Impact of Desalination on Physical and Mechanical Properties of Lanzhou Loess

Science.gov (United States)

Bing, Hui; Zhang, Ying; Ma, Min

2017-12-01

Soluble salt in soil has a significant influence on the physical and mechanical properties of the soil. We performed desalination experiments on Lanzhou loess, a typical sulfate saline soil, to study the effects of salt on the physical and mechanical properties of the loess and compare variations in the soil properties after desalination. The Atterberg limits of the soil increased after desalination as a result of changes in the soil particle composition and grain refinement. The shear and uniaxial compressive strength of the soil increased as a result of decreased calcitic cementation and other changes to the soil structure. Scanning electron microstructure (SEM) and mercury intrusion porosimetry (MIP) procedures revealed changes to the microstructure and pore-size distribution of the Lanzhou loess after desalination.

Evolution of microstructure, strain and physical properties in oxide nanocomposite films.

Science.gov (United States)

Chen, Aiping; Weigand, Marcus; Bi, Zhenxing; Zhang, Wenrui; Lü, Xuejie; Dowden, Paul; MacManus-Driscoll, Judith L; Wang, Haiyan; Jia, Quanxi

2014-06-24

We, using LSMO:ZnO nanocomposite films as a model system, have studied the effect of film thickness on the physical properties of nanocomposites. It shows that strain, microstructure, as well as magnetoresistance strongly rely on film thickness. The magnetotransport properties have been fitted by a modified parallel connection channel model, which is in agreement with the microstructure evolution as a function of film thickness in nanocomposite films on sapphire substrates. The strain analysis indicates that the variation of physical properties in nanocomposite films on LAO is dominated by strain effect. These results confirm the critical role of film thickness on microstructures, strain states, and functionalities. It further shows that one can use film thickness as a key parameter to design nanocomposites with optimum functionalities.

Tillage effects on soil. Physical properties and sunflower ...

African Journals Online (AJOL)

Soil physical properties and sunflower (Helianthus annuus) yield under convectional tillage (CT) and zero-tillage (Z,TJ. was monitored for 3 consecutive years in Ilorin, Southern Guinea Savannah zone of Nigeria (SGSZN). While bulk density of CT increased slightly over the years, significant decrease of 12 and 8% were ...

Psychometric properties of the Fagerström Test for Nicotine Dependence As propriedades psicométricas do Teste de Fagerström para Dependência de Nicotina

Directory of Open Access Journals (Sweden)

Izilda Carolina de Meneses-Gaya

2009-01-01

Full Text Available OBJECTIVE: The Fagerström Test for Nicotine Dependence (FTND is a screening instrument for physical nicotine dependence and is extensively used in various countries. The objective of the present report was to review articles related to the psychometric properties of the FTND. METHODS: A systematic search for articles published up through December of 2007 was carried out in various electronic databases. The following search terms were used: "Fagerström Test for Nicotine Dependence"; "FTND"; "psychometric"; "validity"; "reliability"; "feasibility"; and "factors". We included articles published in English, Spanish or Portuguese and in which the psychometric properties of the FTND were evaluated. RESULTS: Twenty-six studies related to the psychometric properties of the FTND were identified in the indexed literature. Analysis of the studies confirmed the reliability of the FTND for the assessment of nicotine dependence in different settings and populations. CONCLUSIONS: Further validation studies using previously validated instruments as a comparative measure are needed before the extensive use of the FTND can be justified on the basis of its psychometric qualities.OBJETIVO: O Fagerström Test for Nicotine Dependence (FTND, Teste de Fagerström para Dependência de Nicotina é um instrumento de rastreamento para dependência física de tabaco, amplamente utilizado em diversos países. Objetivou-se realizar uma revisão de artigos relacionados às propriedades psicométricas do FTND. MÉTODOS: Uma busca sistemática foi realizada usando-se vários indexadores eletrônicos até dezembro de 2007, com os seguintes descritores: "Fagerström Test for Nicotine Dependence"; "FTND"; "psychometric"; "validity"; "reliability"; "feasibility"; e "factors". Foram incluídos os artigos relacionados à avaliação das propriedades psicométricas do FTND publicados em inglês, espanhol e português. RESULTADOS: Vinte e seis estudos relativos às propriedades psicom

Physical properties of organic and biomaterials: Fundamentals and applications

Science.gov (United States)

Steven, Eden

Silk materials are natural protein-based materials with an exceptional toughness. In addition to their toughness, silk materials also possess complex physical properties and functions resulting from a particular set of amino-acid arrangement that produces structures with crystalline beta-sheets connected by amorphous chains. Extensive studies have been performed to study their structure-function relationship leading to recent advancements in bio-integrated devices. Applications to fields other than textiles and biomedicine, however, have been scarce. In this dissertation, an investigation of the electronic properties, functionalization, and role of silk materials (spider silk and Bombyx mori cocoon silk) in the field of organic materials research is presented. The investigation is conducted from an experimental physics point of view where correlations with charge transport mechanisms in disordered, semiconducting, and insulating materials are made when appropriate. First, I present the electronic properties of spider silk fibers under ambient, humidified, iodized, polar solvent exposure, and pyrolized conditions. The conductivity is exponentially dependent on relative humidity changes and the solvent polarity. Iodine doping increases the conductivity only slightly but has pronounced effects on the pyrolization process, increasing the yield and flexibility of the pyrolized silk fibers. The iodized samples were further studied using magic angle spinning nuclear magnetic resonance (MAS-NMR) and Fourier transform infrared spectroscopy (FTIR) revealing non-homogenous iodine doping and I2 induced hydrogenation that are responsible for the minimal conductivity improvement and the pyrolization effects, respectively. Next, I present the investigation of silk fiber functionalization with gold and its role in electrical measurements. The gold functionalized silk fiber (Au-SS) is metallic down to cryogenic temperatures, has a certain amount of flexibility, and possesses

Italian Physical Society Beyond the Standard Model physics to be observed in precisely measured top quark properties

CERN Document Server

Franceschini, R

2017-01-01

In this contribution I will highlight the new challenges for top quark physics at LHC Run II, focusing in particular on the interplay between precision studies on the top quark and searches for new physics. A new strategy to search for subtle scenarios of new physics is envisaged. The ability to very accurately compute and measure top quark properties such as its production rate, decay rates and distributions, and specific features in the distribution of variables sensitive to the top quark mass is put at the center of this strategy to probe new physics.

Proximate Composition, Physical and Sensory Properties of Non ...

African Journals Online (AJOL)

Objective: The objective of the study was to investigate the possibility of preparing non-wheat cakes using acha and Bambara nut flour blends and generate base line data on the chemical, physical and sensory properties of the cakes. Materials and methods: Acha grains and Bambara nut seeds were processed into flour ...

Relationship between nano/micro structure and physical properties of TiO2-sodium caseinate composite films.

Science.gov (United States)

Montes-de-Oca-Ávalos, Juan Manuel; Altamura, Davide; Candal, Roberto Jorge; Scattarella, Francesco; Siliqi, Dritan; Giannini, Cinzia; Herrera, María Lidia

2018-03-01

Films obtained by casting, starting from conventional emulsions (CE), nanoemulsions (NE) or their gels, which led to different structures, with the aim of explore the relationship between structure and physical properties, were prepared. Sodium caseinate was used as the matrix, glycerol as plasticizer, glucono-delta-lactone as acidulant to form the gels, and TiO 2 nanoparticles as reinforcement to improve physical behavior. Structural characterization was performed by SAXS and WAXS (Small and Wide Angle X-ray Scattering, respectively), combined with confocal and scanning electron microscopy. The results demonstrate that the incorporation of the lipid phase does not notably modify the mechanical properties of the films compared to solution films. Films from NE were more stable against oil release than those from CE. Incorporation of TiO 2 improved mechanical properties as measured by dynamical mechanical analysis (DMA) and uniaxial tensile tests. TiO 2 macroscopic spatial distribution homogeneity and the nanostructure character of NE films were confirmed by mapping the q-dependent scattering intensity in scanning SAXS experiments. SAXS microscopies indicated a higher intrinsic homogeneity of NE films compared to CE films, independently of the TiO 2 load. NE-films containing structures with smaller and more homogeneously distributed building blocks showed greater potential for food applications than the films prepared from sodium caseinate solutions, which are the best known films. Copyright © 2017 Elsevier Ltd. All rights reserved.

The influence of calcination on the physical and chemical properties of petroleum and mixed cokes

Energy Technology Data Exchange (ETDEWEB)

Sikora, K; Syrek, H

1980-01-01

Freshly prepared petroleum and coal-petroleum cokes, before utilization for the production of various materials, are subjected to calcining--thermal treatment in a neutral or reducing atmosphere without the admission of air at less than or equal to 1400/sup 0/. During calcining, stabilization of the physical and chemical properties of the cokes takes place. The properties of the obtained coke depend chiefly on the calcining time and temperature. During calcining, volatile substances are removed almost completely from the coke; the coke density is increased, and its structure is put in order; the electrical conductivity is improved; the mechanical strength is increased; and the reactivity of the coke is decreased. Laboratory studies were conducted on calcining mixed coal-petroleum cokes of two grades at 1200, 1250, and 1300/sup 0/ for 2-6 h. In the calcining products the content of volatile substances, the ash content, S content, and density were determined. It was ascertained that calcining of mixed coal-petroleum cokes goes analogously to calcining of pure petroleum cokes. Raising the temperature and increasing the time of calcining has a substantial effect on improvement of coke physical and chemical properties. For high-quality coke, calcining is to be carried out at greater than or equal to 1300/sup 0/ for 4-6 h, for ordinary coke at > 1200/sup 0/ and greater than or equal to 4 h. The results are regarded as starting data for an industrial study of the calcining process.

Unraveling the size-dependent optical properties of dissolved organic matter

DEFF Research Database (Denmark)

Wünsch, Urban; Stedmon, Colin; Tranvik, Lars

2018-01-01

The size-dependent optical properties of dissolved organic matter (DOM) from four Swedish lakes were investigated using High Performance Size Exclusion Chromatography (HPSEC) in conjunction with online characterization of absorbance (240–600 nm) and fluorescence (excitation: 275 nm, emission: 300....... This study demonstrates the potential for HPSEC and novel mathematical approaches to provide unprecedented insights into the relationship between optical and chemical properties of DOM in aquatic systems...

Evaluation of correlation between physical properties and ultrasonic pulse velocity of fired clay samples.

Science.gov (United States)

Özkan, İlker; Yayla, Zeliha

2016-03-01

The aim of this study is to establish a correlation between physical properties and ultrasonic pulse velocity of clay samples fired at elevated temperatures. Brick-making clay and pottery clay were studied for this purpose. The physical properties of clay samples were assessed after firing pressed clay samples separately at temperatures of 850, 900, 950, 1000, 1050 and 1100 °C. A commercial ultrasonic testing instrument (Proceq Pundit Lab) was used to evaluate the ultrasonic pulse velocity measurements for each fired clay sample as a function of temperature. It was observed that there became a relationship between physical properties and ultrasonic pulse velocities of the samples. The results showed that in consequence of increasing densification of the samples, the differences between the ultrasonic pulse velocities were higher with increasing temperature. These findings may facilitate the use of ultrasonic pulse velocity for the estimation of physical properties of fired clay samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Chemical and Physical Properties of Hi-Cal-2

Science.gov (United States)

Spakowski, A. E.; Allen, Harrison, Jr.; Caves, Robert M.

1955-01-01

As part of the Navy Project Zip to consider various boron-containing materials as possible high-energy fuels, the chemical and physical properties of Hi-Cal-2 prepared by the Callery Chemical Company were evaluated at the NACA Lewis laboratory. Elemental chemical analysis, heat of combustion, vapor pressure and decomposition, freezing point, density, self ignition temperature, flash point, and blow-out velocity were determined for the fuel. Although the precision of measurement of these properties was not equal to that obtained for hydrocarbons, this special release research memorandum was prepared to make the data available as soon as possible.

Moisture relations and physical properties of wood

Science.gov (United States)

Samuel V. Glass; Samuel L. Zelinka

2010-01-01

Wood, like many natural materials, is hygroscopic; it takes on moisture from the surrounding environment. Moisture exchange between wood and air depends on the relative humidity and temperature of the air and the current amount of water in the wood. This moisture relationship has an important influence on wood properties and performance. Many of the challenges of using...

Physical and Chemical Properties of Some Selected Rice Varieties

African Journals Online (AJOL)

User

Physical and chemical properties of nine rice varieties grown and processed in Ebonyi .... Therefore, one tonne of a slender variety of rice will need more storage space than the ..... during washing and boiling of milled rice Starch 36:386-390.

Spin-dependent relativistic effect on heavy quarkonium properties in medium

International Nuclear Information System (INIS)

Dong Yubing

1997-01-01

Spin-dependent relativistic effect on the binding and dissociation of the heavy quarkonium in a thermal environment is investigated. The result shows that the interactions could influence the heavy quarkonium properties in medium

Structural dependence of the galvanomagnetic properties of transition-metal aluminide thin films

CERN Document Server

Kim, K W; Jeong, M H; Lee, Y P; Rhee, J Y

1999-01-01

The structural dependences of the galvanomagnetic properties of Co-Al and Fe-Al alloy films were investigated in this study. Ordered and disordered alloy films with thickness of 150 nm were prepared by using the flash evaporation technique on the heated and cooled substrates, respectively. The temperature dependence of resistance was measured in the range of 2 approx 300 K range with and without a magnetic field of 0.5 T. The influence of the order-disorder structural transition on the temperature dependence of the resistance is discussed in connection with the results for the magnetic properties and is analyzed in the framework of the partial localization of the electronic states and variable-range hopping conductivity.

PHYSICAL AND MECHANICAL PROPERTIES OF JUVENILE Schizolobium amazonicum WOOD

Directory of Open Access Journals (Sweden)

Graziela Baptista Vidaurre

2018-03-01

Full Text Available ABSTRACT Growth in world demand for wood implies a search for new fast growing species with silvicultural potential, and in this scenario for native species such as Paricá . Thus, the objective of this study was determining the physical and mechanical wood properties of the Schizolobium amazonicum species (known as Paricá in Brazil. Trees were collected from commercial plantations located in the north of Brazil with ages of 5, 7, 9 and 11 years. Four logs from trees of each age in the longitudinal direction of the trees were obtained, and later a diametrical plank of each log was taken to manufacture the specimens which were used to evaluate some physical and mechanical properties of the wood. The basic density of Paricá was reduced in the basetop direction and no difference between the radial positions was observed, while the average basic density of this wood was characterized as low. The region close to the bark showed less longitudinal contraction and also greater homogeneity of this property along the trunk, while for tangential contraction the smallest variation was found in the region near the pith. Paricá wood contraction was characterized as low. Age influenced most of the mechanical properties, where logs from the base had the highest values of mechanical strength.

Time dependency in the mechanical properties of crystalline rocks. A literature survey

International Nuclear Information System (INIS)

Hagros, A.; Johansson, E.; Hudson, J.A.

2008-09-01

Because of the long design life, elevated temperatures, and the location at depth (high stresses), time-dependent aspects of the mechanical properties of crystalline rock are potentially important for the design and the long term safety of the radioactive waste repository at Olkiluoto. However, time-dependent effects in rock mechanics are still one of the least understood aspects of the physical behaviour of rock masses, this being partly due to the fact that it is difficult to conduct long-term experimental tests - either in the laboratory or in situ. Yet, the time-dependent mechanical behaviour needs to be characterised so that it can be included in the modelling studies supporting repository design. The Introduction explains the background to the literature survey and includes definitions of the terms 'creep' (increasing strain at constant stress) and 'stress relaxation' (decreasing stress at constant strain). Moreover, it is noted that the rock around an in situ excavation is loaded by the adjacent rock elements and so the timedependent behaviour will depend on the unloading stiffness of these and hence will not actually be either pure creep or pure stress relaxation. The Appendix contains the results of the literature survey of reported time-dependent research as it applies to crystalline rock. A summary of each of the 38 literature items is presented in tabular form covering document number, subject area, document reference, subject matter, objectives, methodology, highlighted figures, conclusions and comments. It is concluded that the time-dependent failure strength of all rocks observed may be interpreted by sub-critical crack growth assisted by the stress corrosion mechanism. Also, certain parameters are known to affect the long-term properties: mineralogy, grain size, water/water chemistry, confining stress and loading history. At some point in the loading history of rock, the state of crack development reaches a point whereby the continued generation of

Optimization of the sampling scheme for maps of physical and chemical properties estimated by kriging

Directory of Open Access Journals (Sweden)

Gener Tadeu Pereira

2013-10-01

Full Text Available The sampling scheme is essential in the investigation of the spatial variability of soil properties in Soil Science studies. The high costs of sampling schemes optimized with additional sampling points for each physical and chemical soil property, prevent their use in precision agriculture. The purpose of this study was to obtain an optimal sampling scheme for physical and chemical property sets and investigate its effect on the quality of soil sampling. Soil was sampled on a 42-ha area, with 206 geo-referenced points arranged in a regular grid spaced 50 m from each other, in a depth range of 0.00-0.20 m. In order to obtain an optimal sampling scheme for every physical and chemical property, a sample grid, a medium-scale variogram and the extended Spatial Simulated Annealing (SSA method were used to minimize kriging variance. The optimization procedure was validated by constructing maps of relative improvement comparing the sample configuration before and after the process. A greater concentration of recommended points in specific areas (NW-SE direction was observed, which also reflects a greater estimate variance at these locations. The addition of optimal samples, for specific regions, increased the accuracy up to 2 % for chemical and 1 % for physical properties. The use of a sample grid and medium-scale variogram, as previous information for the conception of additional sampling schemes, was very promising to determine the locations of these additional points for all physical and chemical soil properties, enhancing the accuracy of kriging estimates of the physical-chemical properties.

Change in physical properties of high density isotropic graphites irradiated in the ?JOYO? fast reactor

Science.gov (United States)

Maruyama, T.; Kaito, T.; Onose, S.; Shibahara, I.

1995-08-01

Thirteen kinds of isotropic graphites with different density and maximum grain size were irradiated in the experimental fast reactor "JOYO" to fluences from 2.11 to 2.86 × 10 26 n/m 2 ( E > 0.1 MeV) at temperatures from 549 to 597°C. Postirradiation examination was carried out on the dimensional changes, elastic modulus, and thermal conductivity of these materials. Dimensional change results indicate that the graphites irradiated at lower fluences showed shrinkage upon neutron irradiation followed by increase with increasing neutron fluences, irrespective of differences in material parameters. The Young's modulus and Poisson's ratio increased by two to three times the unirradiated values. The large scatter found in Poisson's ratio of unirradiated materials became very small and a linear dependence on density was obtained after irradiation. The thermal conductivity decreased to one-fifth to one-tenth of unirradiated values, with a negligible change in specific heat. The results of postirradiation examination indicated that the changes in physical properties of high density, isotropic graphites were mainly dominated by the irradiation condition rather than their material parameters. Namely, the effects of irradiation induced defects on physical properties of heavily neutron-irradiated graphites are much larger than that of defects associated with as-fabricated specimens.

Change in physical properties of high density isotropic graphites irradiated in the ''JOYO'' fast reactor

International Nuclear Information System (INIS)

Maruyama, T.; Kaito, T.; Onose, S.; Shibahara, I.

1995-01-01

Thirteen kinds of isotropic graphites with different density and maximum grain size were irradiated in the experimental fast reactor ''JOYO'' to fluences from 2.11 to 2.86x10 26 n/m 2 (E>0.1 MeV) at temperatures from 549 to 597 C. Postirradiation examination was carried out on the dimensional changes, elastic modulus, and thermal conductivity of these materials. Dimensional change results indicate that the graphites irradiated at lower fluences showed shrinkage upon neutron irradiation followed by increase with increasing neutron fluences, irrespective of differences in material parameters. The Young's modulus and Poisson's ratio increased by two to three times the unirradiated values. The large scatter found in Poisson's ratio of unirradiated materials became very small and a linear dependence on density was obtained after irradiation. The thermal conductivity decreased to one-fifth to one-tenth of unirradiated values, with a negligible change in specific heat. The results of postirradiation examination indicated that the changes in physical properties of high density, isotropic graphites were mainly dominated by the irradiation condition rather than their material parameters. Namely, the effects of irradiation induced defects on physical properties of heavily neutron-irradiated graphites are much larger than that of defects associated with as-fabricated specimens. (orig.)

Physical and rheological properties of Titanium Dioxide modified asphalt

Science.gov (United States)

Buhari, Rosnawati; Ezree Abdullah, Mohd; Khairul Ahmad, Mohd; Chong, Ai Ling; Haini, Rosli; Khatijah Abu Bakar, Siti

2018-03-01

Titanium Dioxide (TiO2) has been known as a useful photocatalytic material that is attributed to the several characteristics includes high photocatalytic activity compared with other metal oxide photocatalysts, compatible with traditional construction materials without changing any original performance. This study investigates the physical and rheological properties of modified asphalt with TiO2. Five samples of asphalt with different concentration of TiO2 were studied, namely asphalt 2%, 4%, 6% 8% and 10% TiO2. The tests includes are penetration, softening point, ductility, rotational viscosity and dynamic shear rheometer (DSR) test. From the results of this study, it is noted that addition of TiO2 has significant effect on the physical properties of asphalt. The viscosity tests revealed that asphalt 10% TiO2 has good workability among with reducing approximately 15°C compared to base asphalt. Based on the results from DSR measurements, asphalt 10% TiO2 has reduced temperature susceptibility and increase stiffness and elastic behaviour in comparison to base asphalt. As a result, TiO2 can be considered to be an additive to modify the properties of asphalt.

Physical dependence increases the relative reinforcing effects of caffeine versus placebo.

Science.gov (United States)

Garrett, B E; Griffiths, R R

1998-10-01

Using a within-subject cross-over design, this study examined the role of physical dependence in caffeine reinforcement by experimentally manipulating physical dependence. Each subject was exposed to two chronic drug phases (300 mg/70 kg/day caffeine and placebo) for 9-12 days, with order of phases counterbalanced across subjects. On 2 separate days immediately following each of the chronic drug exposures, subjects received acute doses of either caffeine (300 mg/70 kg) or placebo in counterbalanced order. The reinforcing effects of these drugs were then determined by using a multiple-choice procedure in which subjects made a series of discrete choices between receiving varying amounts of money or receiving the drug again, and a choice between the two drugs. To ensure that subjects completed the form carefully, following exposure to both of the acute drug administrations, one of the subject's previous choices from the multiple-choice form was randomly selected and the consequence of that choice was implemented. When subjects were maintained on chronic caffeine, they were willing to forfeit significantly more money and showed significant increases in typical withdrawal symptoms (e.g. fatigue, mood disturbance) after receiving placebo as compared to the other three conditions. When subjects were maintained on chronic caffeine, they also chose to receive caffeine over placebo twice as often than when they were maintained on chronic placebo. These findings provide the strongest evidence to date indicating that caffeine physical dependence increases the relative reinforcing effects of caffeine versus placebo.

Low temperature physical properties of Co-35Ni-20Cr-10Mo alloy MP35N®

Science.gov (United States)

Lu, J.; Toplosky, V. J.; Goddard, R. E.; Han, K.

2017-09-01

Multiphase Co-35Ni-20Cr-10Mo alloy MP35N® is a high strength alloy with excellent corrosion resistance. Its applications span chemical, medical, and food processing industries. Thanks to its high modulus and high strength, it found applications in reinforcement of ultra-high field pulsed magnets. Recently, it has also been considered for reinforcement in superconducting wires used in ultra-high field superconducting magnets. For these applications, accurate measurement of its physical properties at cryogenic temperatures is very important. In this paper, physical properties including electrical resistivity, specific heat, thermal conductivity, and magnetization of as-received and aged samples are measured from 2 to 300 K. The electrical resistivity of the aged sample is slightly higher than the as-received sample, both showing a weak linear temperature dependence in the entire range of 2-300 K. The measured specific heat Cp of 430 J/kg-K at 295 K agrees with a theoretical prediction, but is significantly smaller than the values in the literature. The thermal conductivity between 2 and 300 K is in good agreement with the literature which is only available above 77 K. Magnetic property of MP35N® changes significantly with aging. The as-received sample exhibits Curie paramagnetism with a Curie constant C = 0.175 K. While the aged sample contains small amounts of a ferromagnetic phase even at room temperature. The measured MP35N® properties will be useful for the engineering design of pulsed magnets and superconducting magnets using MP35N® as reinforcement.

Physical Properties of Fractured Porous Media

Science.gov (United States)

Mohammed, T. E.; Schmitt, D. R.

2015-12-01

The effect of fractures on the physical properties of porous media is of considerable interest to oil and gas exploration as well as enhanced geothermal systems and carbon capture and storage. This work represents an attempt to study the effect fractures have on multiple physical properties of rocks. An experimental technique to make simultaneous electric and ultrasonic measurements on cylindrical core plugs is developed. Aluminum end caps are mounted with ultrasonic transducers to transmit pules along the axis of the cylinder while non-polarizing electrodes are mounted on the sides of the core to make complex conductivity measurements perpendicular to the cylinder axis. Electrical measurements are made by applying a sinusoidal voltage across the measurement circuit that consist of a resister and the sample in series. The magnitude and phase of the signal across the sample is recorded relative to the input signal across a range of frequencies. Synthetic rock analogs are constructed using sintered glass beads with fractures imbedded in them. The fracture location, size and orientation are controlled and each fractured specimen has an unfractured counterpart. Porosity, Permeability, electrical conductivity and ultrasonic velocity measurements are conducted on each sample with the complex electrical conductivities recorded at frequencies from 10hz to 1 Mhz. These measurements allow us to examine the changes induced by these mesoscale fractures on the embedding porous medium. Of particular interest is the effect of fracture orientation on electrical conductivity of the rock. Seismic anisotropy caused by fractures is a well understood phenomenon with many rock physics models dedicated to its understanding. The effect of fractures on electrical conductivity is less well understood with electrical anisotropy scarcely investigated in the literature. None the less, using electrical conductivity to characterize fractures can add an extra constraint to characterization based

Physical property characterization of 183-H Basin sludge

International Nuclear Information System (INIS)

Biyani, R.K.; Delegard, C.H.

1995-01-01

This document describes the characterization of 183-H Basin sludge physical properties, e.g. bulk density of sludge and absorbent, and determination of free liquids. Calcination of crucible-size samples of sludge was also done and the resulting 'loss-on-ignition' was compared to the theoretical weight loss based on sludge analysis obtained from Weston Labs

Order-of-magnitude physics of neutron stars. Estimating their properties from first principles

Energy Technology Data Exchange (ETDEWEB)

Reisenegger, Andreas; Zepeda, Felipe S. [Pontificia Universidad Catolica de Chile, Instituto de Astrofisica, Facultad de Fisica, Macul (Chile)

2016-03-15

We use basic physics and simple mathematics accessible to advanced undergraduate students to estimate the main properties of neutron stars. We set the stage and introduce relevant concepts by discussing the properties of ''everyday'' matter on Earth, degenerate Fermi gases, white dwarfs, and scaling relations of stellar properties with polytropic equations of state. Then, we discuss various physical ingredients relevant for neutron stars and how they can be combined in order to obtain a couple of different simple estimates of their maximum mass, beyond which they would collapse, turning into black holes. Finally, we use the basic structural parameters of neutron stars to briefly discuss their rotational and electromagnetic properties. (orig.)

Stone crayfish in the Czech Republic: how does its population density depend on basic chemical and physical properties of water?

Directory of Open Access Journals (Sweden)

Vlach P.

2013-03-01

Full Text Available The stone crayfish (Austropotamobius torrentium Schrank is one of the two native crayfish species in the Czech Republic. The populations as well as physical and chemical parameters of water (pH, conductivity, dissolved oxygen, undissolved particles, NH3, NH4+, NO2−, NO3−, phosphorus, Ca2+ and SO42 −  of 33 streams were examined to find the ecological plasticity of this crayfish and some relations between these parameters and population densities. The mentioned parameters often significantly varied at the sites. Two approaches were applied to find relations between these parameters and observed abundance. At first, the observed streams were compared using RDA (streams  ×  physical-chemical parameters. No significance was found while testing relationship between the streams grouped along the 1st axis of model and the observed abundances of stone crayfish. However, some correlations between abundance and conductivity, calcium, nitrates and sulphates were found using polynomial regression. These relationships are explicable in terms of mutual correlations, underlying geology and other factors which affect abundances. In conclusion, A. torrentium is able to inhabit waters with a large range of physical and chemical parameters of the water without any fundamental influence on population densities. Water properties play an indisputable role as limiting ecological factors at uncommon concentrations, but population densities are probably influenced much more by the types of habitats, habitat features, predation and other ecological factors.

Direct Comparison of Physical Properties of Bacillus subtilis NCIB 3610 and B-1 Biofilms

Science.gov (United States)

Kesel, Sara; Grumbein, Stefan; Gümperlein, Ina; Tallawi, Marwa; Marel, Anna-Kristina

2016-01-01

Many bacteria form surface-attached communities known as biofilms. Due to the extreme resistance of these bacterial biofilms to antibiotics and mechanical stresses, biofilms are of growing interest not only in microbiology but also in medicine and industry. Previous studies have determined the extracellular polymeric substances present in the matrix of biofilms formed by Bacillus subtilis NCIB 3610. However, studies on the physical properties of biofilms formed by this strain are just emerging. In particular, quantitative data on the contributions of biofilm matrix biopolymers to these physical properties are lacking. Here, we quantitatively investigated three physical properties of B. subtilis NCIB 3610 biofilms: the surface roughness and stiffness and the bulk viscoelasticity of these biofilms. We show how specific biomolecules constituting the biofilm matrix formed by this strain contribute to those biofilm properties. In particular, we demonstrate that the surface roughness and surface elasticity of 1-day-old NCIB 3610 biofilms are strongly affected by the surface layer protein BslA. For a second strain, B. subtilis B-1, which forms biofilms containing mainly γ-polyglutamate, we found significantly different physical biofilm properties that are also differently affected by the commonly used antibacterial agent ethanol. We show that B-1 biofilms are protected from ethanol-induced changes in the biofilm's stiffness and that this protective effect can be transferred to NCIB 3610 biofilms by the sole addition of γ-polyglutamate to growing NCIB 3610 biofilms. Together, our results demonstrate the importance of specific biofilm matrix components for the distinct physical properties of B. subtilis biofilms. PMID:26873313

SIFAT FISIK, KIMIA, DAN FUNGSIONAL DAMAR [Brief Review on: Physical, Chemical and Functional Properties of Dammar

Directory of Open Access Journals (Sweden)

Noryawati Mulyono1

2004-12-01

Full Text Available Dammar is one of Indonesian forestry products which is abundant. It has unique physical, chemical and functional properties. The important physical properties of dammar include its solubility in some organic solvents, softening temperature, viscosity and its absorbance. The important chemical properties reviewed here include its properties as resin, composition of terpenoid compounds present in dammar, and essential oil yielded from distillation of fresh dammar. Physical and chemical properties of dammar need to be studied further in order to optimize its functional properties. So far, dammar is widely used as weighting agent and source of essential oil. However, now, some species of dammar are being explored and developed for sal flour, fat source, triacylglycerol substituent for cocoa butter and wood preservatives.

Granular activated carbons from broiler manure: physical, chemical and adsorptive properties.

Science.gov (United States)

Lima, Isabel M; Marshall, Wayne E

2005-04-01

Broiler manure produced at large concentrated facilities poses risks to the quality of water and public health. This study utilizes broiler litter and cake as source materials for granular activated carbon production and optimizes conditions for their production. Pelletized manure samples were pyrolyzed at 700 degrees C for 1 h followed by activation in an inert atmosphere under steam at different water flow rates, for a period ranging from 15 to 75 min. Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant, yields varied from 18% to 28%, surface area varied from 253 to 548 m2/g and copper ion adsorption varied from 0.13 to 1.92 mmol Cu2+/g carbon. Best overall performing carbons were steam activated for 45 min at 3 ml/min. Comparative studies with commercial carbons revealed the broiler cake-based carbon as having the highest copper ion efficiency.

Physical and performance properties of coal tar urethanes - pipe

International Nuclear Information System (INIS)

Hickney, J.; Hendry, M.

1984-01-01

The purpose of this paper is to review certain physical properties of coal tar extended urethane coatings designed specifically for use in the pipe coatings market. The blend of coal tar and urethane resins provides a novel finished product with properties cumulatively inherent in its constituents. Typically, coal tar and coal tar pitch offer exceptional water resistance and cathodic alkali resistance when blended with other resins. An example is the standard coal tar epoxies used for many years in the marine markets for shipbottoms

Identifying the Physical Properties of Showers That Influence User Satisfaction to Aid in Developing Water-Saving Showers

Directory of Open Access Journals (Sweden)

Minami Okamoto

2015-07-01

Full Text Available This research was conducted with the goal of clarifying the required conditions of water-saving showerheads. In order to this, the research analyzes the mutual relationship between water usage flow, the level of satisfaction and the physical properties of spray of showerheads. The physical properties of spray were measured using physical properties test apparatus of standard or scheme for water-saving showerheads issued in several water-saving countries, and satisfaction evaluation data was acquired through bathing experiments. The evaluated showerheads were separated into three groups according to usage water flow and the level of satisfaction. The relationships between usage water flow, the level of satisfaction and physical properties were compared. The results identified that Spray Force and Spray Force-per-Hole were physical properties that influence usage water flow. Spray force-per-hole, water volume ratio in Spray Patterns within φ 100 and φ 150, Temperature Drop and Spray Angle were identified as physical properties that influenced the level of satisfaction. The level of satisfaction and usage water flow has a spurious correlation through the physical properties of Spray Force-per-Hole and Temperature Drop. It is possible to improve the level of satisfaction independent of amount of water usage through designs that set an appropriate value for water volume ratio and Spray Angle for Spray Patterns within φ 100 and φ 150.

Effect on physical properties of laterite soil with difference percentage of sodium bentonite

Science.gov (United States)

Kasim, Nur Aisyah; Azmi, Nor Azizah Che; Mukri, Mazidah; Noor, Siti Nur Aishah Mohd

2017-08-01

This research was carried out in an attempt to know the physical properties of laterite soil with the appearance of difference percentage of sodium bentonite. Lateritic soils usually develop in tropical and other regions with similar hot and humid climate, where heavy rainfall, warm temperature and well drainage lead to the formation of thick horizons of reddish lateritic soil profiles rich in iron and aluminium. When sodium predominates, a large amount of water can be absorbed in the interlayer, resulting in the remarkable swelling properties observed with hydrating sodium bentonite. There are some basic physical properties test conducted in this research which are Specific Gravity Test, pH Test, Sieve Analysis, Hydrometer Test, Shrinkage Limit and Atterberg Limit. The test will be conducted with 0%, 5%, 10%, 15% and 20% of sodium bentonite. Each test will be repeated three times for the accuracy of the result. From the physical properties test the soil properties characteristic react with the sodium bentonite can be determine. Therefore the best percentage of sodium bentonite admixture can be determined for laterite soil. The outcomes of this study give positive results due to the potential of sodium bentonite to improve the laterite soil particle.

PHYSICAL PROPERTY MEASUREMENTS OF LABORATORY PREPARED SALTSTONE GROUT

Energy Technology Data Exchange (ETDEWEB)

Hansen, E.; Cozzi, A.; Edwards, T.

2014-05-05

The Saltstone Production Facility (SPF) built two new Saltstone Disposal Units (SDU), SDU 3 and SDU 5, in 2013. The variable frequency drive (VFD) for the grout transfer hose pump tripped due to high current demand by the motor during the initial radioactive saltstone transfer to SDU 5B on 12/5/2013. This was not observed during clean cap processing on July 5, 2013 to SDU 3A, which is a slightly longer distance from the SPF than is SDU 5B. Saltstone Design Authority (SDA) is evaluating the grout pump performance and capabilities to transfer the grout processed in SPF to SDU 3/5. To assist in this evaluation, grout physical properties are required. At this time, there are no rheological data from the actual SPF so the properties of laboratory prepared samples using simulated salt solution or Tank 50 salt solution will be measured. The physical properties of grout prepared in the laboratory with de-ionized water (DI) and salt solutions were obtained at 0.60 and 0.59 water to premix (W/P) ratios, respectively. The yield stress of the DI grout was greater than any salt grout. The plastic viscosity of the DI grout was lower than all of the salt grouts (including salt grout with admixture). When these physical data were used to determine the pressure drop and fluid horsepower for steady state conditions, the salt grouts without admixture addition required a higher pressure drop and higher fluid horsepower to transport. When 0.00076 g Daratard 17/g premix was added, both the pressure drop and fluid horsepower were below that of the DI grout. Higher concentrations of Daratard 17 further reduced the pressure drop and fluid horsepower. The uncertainty in the single point Bingham Plastic parameters is + 4% of the reported values and is the bounding uncertainty. Two different mechanical agitator mixing protocols were followed for the simulant salt grout, one having a total mixing time of three minutes and the other having a time of 10 minutes. The Bingham Plastic parameters

Physical properties of W gravities and W strings

International Nuclear Information System (INIS)

Das, S.R.; Dhar, A.; Rama, S.K.

1991-01-01

This paper investigates some basic physical properties of W gravities and W strings, using a free field realization. The authors argue that the configuration space of W gravities have global characteristics in addition to the Euler characteristic. The authors identify one such global quantity to be a monopole charge and show how this charge appears in the exponents. The free energy would then involve a θ parameter. Using a BRST procedure the authors find all the physical states of W 3 and W 4 gravities, and show that physical operators are nonsingular composites of the screening charge operators. (The latter are not physical operators for N ≥ 3.) For W strings we show how the W constraints lead to the emergence of a single (and not many) extra dimension coming from the W-gravity sector. By analyzing the resulting dispersion relations the authors find that both the lower and upper critical dimensions are lowered compared to ordinary two-dimensional gravity. The pure W gravity spectrum reveals an intriguing numerological connection with unitary minimal models coupled to ordinary gravity

PHYSICAL AND MECHANICAL PROPERTIES OF Araucaria angustifolia (Bertol. WOOD FOR THREE STRATUM PHYTOSOCIOLOGICAL

Directory of Open Access Journals (Sweden)

Rafael Beltrame

2010-11-01

Full Text Available The study of physical and mechanical properties of wood is essential for industrial use both in construction and the manufacture of furniture. Thus, the study aimed to determine the physical and mechanical properties of the Araucaria angustifolia wood in terms of three strata phytosociological. For this, 15 trees were felled, five belonging to the upper stratum, the middle stratum five and five for the lower strata. The trees were deployed for the preparation of specimens used for mechanical testing. In the mechanical characterization of the species assays were performed for impact resistance, static bending, compression axial and perpendicular to the fibers. As for the characterization of physical properties, determined the apparent specific gravity at 12% relative humidity for each extract. The results did not show significant differences in the tests of impact resistance and static bending to the strata phytosociological. As for the apparent specific gravity, compression axial and perpendicular there was a change in the values of propertiesbetween the strata phytosociological, is generally butter in the middle and upper strata. Therefore the physical and mechanical properties tend to present higher values these two strata. The data analysis allowed of Araucaria angustifolia wood has moderate mechanical strength when compared with other species studies.

Molecular clips based on propanediurea : synthesis and physical properties

NARCIS (Netherlands)

Jansen, Robertus Johannes

2002-01-01

This thesis describes the synthesis and physical properties of a series of molecular clips derived from the concave molecule propanediurea. These molecular clips are cavity-containing receptors that can bind a variety of aromatic guests. This binding is a result of hydrogen bonding and pi-pi

Evaluation of properties of low activation Mn-Cr steel (2). Physical properties and aging properties

Energy Technology Data Exchange (ETDEWEB)

Saito, Shigeru; Fukaya, Kiyoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ishiyama, Shintaro [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Sato, Ikuo; Kusuhashi, Mikio; Hatakeyama, Takeshi [Japan Steel Works Ltd., Muroran, Hokkaido (Japan). Muroran Plant; Takahashi, Heishichiro [Hokkaido Univ., Sapporo (Japan); Kikuchi, Mitsuru [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

2000-08-01

The JT-60SU (Super Upgrade) program is under discussion at JAERI. Its design optimization activity requires the vacuum vessel material to be non-magnetic, very strong and with low induced activation. However, there is no suitable material available to fulfill all the requirements. JAERI started to develop a new material for the vacuum vessel together with the Japan Steel Works LTD. (JSW). Chemical composition and metallurgical processes were optimized and a new steel named VC9, which has the composition of Cr :16wt%, Mn :15.5wt%, C :0.2wt%, N :0.2wt% with nonmagnetic single {gamma} phase, was selected as a candidate material. Here, physical properties and aging properties of VC9 were studied and the results were compared with those of 316L stainless steel. (author)

[Studies on the physical dependence liability of chlorphenesin carbamate (author's transl)].

Science.gov (United States)

Sasajima, M; Tarumoto, Y; Aihara, H; Tanaka, Y; Saito, S

1977-05-01

Physical dependence liability of chlorphenesin carbamate (CPC) was studied in parallel with phenobarbital-Na (PB). Beagle dogs were used and the overall duration of the experiment was 85 days, i.e. the first dosing period was 42 dyas (6 weeks) in which drugs were repeatedly administered orally once daily, followed by a withdrawal period (7 days), the second dosing period was continued from the 50th-78th day in which the form and schedule of drug administration was as in the first dosing period. The last 79th to 85th days were used for substitution experiments. In both dosing periods, PB but not CPC showed signs of tolerance formation. Severe withdrawal syndrome was observed in PB administered dogs whereas there were no changes of behavior observed in CPC-dogs by withdrawal and substitution procedures, respectively. CPC apparently does not have a physical dependence liability.

Physical and chemical studies of superconduction properties of the intercalation compounds

International Nuclear Information System (INIS)

Eder, F.X.; Lerf, A.

1980-01-01

The superconducting properties of the intercalation compounds of layered dichalcogenides were studied. Our studies were concerned mainly to the alkali metal intercalation derivatives of TaS 2 and NbS 2 , and later on extended to the molecule intercalation compounds. The main difficulties with this class of superconductors result from varying material properties; these are therefore the subject of broad intensity in our investigations. The results received on the physical and chemical properties of the intercalation compounds is utilized for a phenomenological description of the factors mainly determining there superconducting properties. (orig.) [de

Impact of petroleum products on soil composition and physical-chemical properties

Science.gov (United States)

Brakorenko, N. N.; Korotchenko, T. V.

2016-03-01

The article describes the grain-size distribution, physical and mechanical properties, swelling and specific electrical resistivity of soils before and after the contact with petroleum products. The changes in mechanical properties of soils contaminated with petroleum products have been stated. It leads to the increase in compressibility values, decline in internal friction angle and cohesion.

Impact of petroleum products on soil composition and physical-chemical properties

OpenAIRE

Brakorenko, Nataliya Nikolaevna; Korotchenko, Tatiana Valerievna

2016-01-01

The article describes the grain-size distribution, physical and mechanical properties, swelling and specific electrical resistivity of soils before and after the contact with petroleum products. The changes in mechanical properties of soils contaminated with petroleum products have been stated. It leads to the increase in compressibility values, decline in internal friction angle and cohesion.

Time-dependent--S-matrix Hartree-Fock theory of complex reactions

International Nuclear Information System (INIS)

Griffin, J.J.; Lichtner, P.C.; Dworzecka, M.

1980-01-01

Some limitations of the conventional time-dependent Hartree-Fock method for describing complex reactions are noted, and one particular ubiquitous defect is discussed in detail: the post-breakup spurious cross channel correlations which arise whenever several asymptotic reaction channels must be simultaneously described by a single determinant. A reformulated time-dependent--S-matrix Hartree-Fock theory is proposed, which obviates this difficulty. Axiomatic requirements minimal to assure that the time-dependent--S-matrix Hartree-Fock theory represents an unambiguous and physically interpretable asymptotic reaction theory are utilized to prescribe conditions upon the definition of acceptable asymptotic channels. That definition, in turn, defines the physical range of the time-dependent--S-matrix Hartree-Fock theory to encompass the collisions of mathematically well-defined ''time-dependent Hartree-Fock droplets.'' The physical properties of these objects then circumscribe the content of the Hartree-Fock single determinantal description. If their periodic vibrations occur for continuous ranges of energy then the resulting ''classical'' time-dependent Hartree-Fock droplets are seen to be intrinsically dissipative, and the single determinantal description of their collisions reduces to a ''trajectory'' theory which can describe the masses and relative motions of the fragments but can provide no information about specific asymptotic excited states beyond their constants of motion, or the average properties of the limit, if it exists, of their equilibrization process. If, on the other hand, the periodic vibrations of the time-dependent Hartree-Fock droplets are discrete in energy, then the time-dependent--S-matrix Hartree-Fock theory can describe asymptotically the time-average properties of the whole spectrum of such periodic vibrations

Graphical analysis of pH-dependent properties of proteins predicted using PROPKA.

Science.gov (United States)

Rostkowski, Michał; Olsson, Mats H M; Søndergaard, Chresten R; Jensen, Jan H

2011-01-26

Charge states of ionizable residues in proteins determine their pH-dependent properties through their pKa values. Thus, various theoretical methods to determine ionization constants of residues in biological systems have been developed. One of the more widely used approaches for predicting pKa values in proteins is the PROPKA program, which provides convenient structural rationalization of the predicted pKa values without any additional calculations. The PROPKA Graphical User Interface (GUI) is a new tool for studying the pH-dependent properties of proteins such as charge and stabilization energy. It facilitates a quantitative analysis of pKa values of ionizable residues together with their structural determinants by providing a direct link between the pKa data, predicted by the PROPKA calculations, and the structure via the Visual Molecular Dynamics (VMD) program. The GUI also calculates contributions to the pH-dependent unfolding free energy at a given pH for each ionizable group in the protein. Moreover, the PROPKA-computed pKa values or energy contributions of the ionizable residues in question can be displayed interactively. The PROPKA GUI can also be used for comparing pH-dependent properties of more than one structure at the same time. The GUI considerably extends the analysis and validation possibilities of the PROPKA approach. The PROPKA GUI can conveniently be used to investigate ionizable groups, and their interactions, of residues with significantly perturbed pKa values or residues that contribute to the stabilization energy the most. Charge-dependent properties can be studied either for a single protein or simultaneously with other homologous structures, which makes it a helpful tool, for instance, in protein design studies or structure-based function predictions. The GUI is implemented as a Tcl/Tk plug-in for VMD, and can be obtained online at http://propka.ki.ku.dk/~luca/wiki/index.php/GUI_Web.

Improvement on Physical Properties of Pullulan Films by Novel Cross-Linking Strategy.

Science.gov (United States)

Chen, Chieh-Ting; Chen, Kuan-I; Chiang, Hsin-Han; Chen, Yu-Kuo; Cheng, Kuan-Chen

2017-01-01

Pullulan based films possess several advantages, including high transparency, low toxicity, good biodegradability, good mechanical properties, and low oxygen permeability, are preferable for food packaging. The application of pullulan films on food packaging, however, has inherent disadvantage of high water solubility. In this study, glutaraldehyde and glycerol were used as the cross-linking reagent and the plasticizer respectively to improve water resistance and physical properties of the pullulan films. Effects of cross-linking degree on physical properties, including water absorptions, swelling behaviors, water vapor permeability and tensile strengths of films were evaluated. FTIR results demonstrated that the pullulan films were successfully cross-linked by glutaraldehyde. The tensile strength of pullulan films could be enhanced significantly (P permeability. © 2016 Institute of Food Technologists®.

Effect of Irrigation with Wastewater on Certain Soil Physical and Chemical properties

Directory of Open Access Journals (Sweden)

Farzad Rohani Shahraki

2005-03-01

Full Text Available Depending on effluent characteristics, irrigation with wastewater plant effluent can be either beneficial or harmful. To investigate the effects of nine years of irrigation with North Isfahan Wastewater Treatment Plant effluent on physical and chemical properties of soil, a study was carried out using a randomized complete block design with three replications. Treatments included: 1 raw wastewater; 2 effluent from primary settling basin; 3 final plant effluent and 4 well water. To investigate soil physical and chemical properties, samples were taken from depths of 0-5 cm and 5-10 cm from each plot. The results showed that raw wastewater COD and SS were higher than the Iranian Standard limits for use in irrigation. So were BOD5 and turbidity of effluent from primary sedimentation tanks. From the results obtained, the raw wastewater may be considered to be of medium quality. However, regarding other parameters such as EC, SAR, Na and Pb, the quality of the raw wastewater was considerably higher than that of well water. All treatments showed medium infiltrability with respect to chloride concentration. The concentration of lead in well water was higher than in treated wastewater. It should be noted that lead concentration in all samples was less than the standard limits. The average soil bulk density and percentage of moisture in FC did not follow any specific trend. The results indicate that the soil irrigated with effluent over the nine years had a lower bulk density, a higher percentage of moisture, and a lower infiltration compared to adjacent soil not irrigated with wastewater. Analysis of variance for all results did not confirm any significant differences among treatments.

Physical properties of a new sonically placed composite resin restorative material.

Science.gov (United States)

Ibarra, Emily T; Lien, Wen; Casey, Jeffery; Dixon, Sara A; Vandewalle, Kraig S

2015-01-01

A new nanohybrid composite activated by sonic energy has been recently introduced as a single-step, bulk-fill restorative material. The purpose of this study was to compare the physical properties of this new composite to various other composite restorative materials marketed for posterior or bulk-fill placement. The following physical properties were examined: depth of cure, volumetric shrinkage, flexural strength, flexural modulus, fracture toughness, and percent porosity. A mean and standard deviation were determined per group. One-way ANOVA and Tukey's post hoc tests were performed per property (α = 0.05). Percent porosity was evaluated with a Kruskal-Wallis/Mann-Whitney test (α = 0.005). Significant differences were found between groups (P composite restorative materials, the new nanohybrid composite showed low shrinkage and percent porosity, moderate fracture toughness and flexural modulus, and high flexural strength. However, it also demonstrated a relatively reduced depth of cure compared to the other composites.

Physical Properties And Maize Production In A Spent Oil ...

African Journals Online (AJOL)

Information on the use of plant species and organic nutrients to improve the physical properties of oil-contaminated soil, with a view to making it conducive for crop production, is very important. Three legumes (Gliricidia sepium, Leucenae leucocephala and Calapogonium caeruleam) combined or not with poultry manure ...

ORBITAL DEPENDENCE OF GALAXY PROPERTIES IN SATELLITE SYSTEMS OF GALAXIES

International Nuclear Information System (INIS)

Hwang, Ho Seong; Park, Changbom

2010-01-01

We study the dependence of satellite galaxy properties on the distance to the host galaxy and the orbital motion (prograde and retrograde orbits) using the Sloan Digital Sky Survey (SDSS) data. From SDSS Data Release 7, we find 3515 isolated satellite systems of galaxies at z -1 . It is found that the radial distribution of early-type satellites in prograde orbit is strongly concentrated toward the host while that of retrograde ones shows much less concentration. We also find the orbital speed of late-type satellites in prograde orbit increases as the projected distance to the host (R) decreases while the speed decreases for those in retrograde orbit. At R less than 0.1 times the host virial radius (R vir,host ), the orbital speed decreases in both prograde and retrograde orbit cases. Prograde satellites are on average fainter than retrograde satellites for both early and late morphological types. The u - r color becomes redder as R decreases for both prograde and retrograde orbit late-type satellites. The differences between prograde and retrograde orbit satellite galaxies may be attributed to their different origin or the different strength of physical processes that they have experienced through hydrodynamic interactions with their host galaxies.

Physical activity level is impaired and diet dependent in preterm newborn pigs

DEFF Research Database (Denmark)

Cao, Muqing; Andersen, Anders Daniel; Van Ginneken, Chris

2015-01-01

and neonatal physical activity. METHODS: In experiment 1, preterm and term pigs were fed parenteral nutrition (PN) or PN plus bovine colostrum (BC, 16-64 ml/kg/d enterally) for 5 d. In experiment 2, preterm pigs were fed PN+BC or PN+formula for 5 d. In experiment 3, preterm pigs were fed BC, formula, or human...... feeding increased HCA, intestinal weights, and necrotizing enteritis resistance, relative to formula (experiment 3). CONCLUSION: Preterm pigs show decreased physical activity, and the first enteral feeds diet dependently stimulate both gut growth and physical activity. The effects may arise from...

Prediction of Solvent Physical Properties using the Hierarchical Clustering Method

Science.gov (United States)

Recently a QSAR (Quantitative Structure Activity Relationship) method, the hierarchical clustering method, was developed to estimate acute toxicity values for large, diverse datasets. This methodology has now been applied to the estimate solvent physical properties including sur...

Dynamics of Physical and Physicochemical Properties of Urban Soils under the Effect of Ice-Melting Salts

Science.gov (United States)

Azovtseva, N. A.; Smagin, A. V.

2018-01-01

Physical (water content, density, and air and water regimes) and physicochemical (electrical conductivity, pH, and SAR) properties of urban soils were investigated on test plots of Moscow to evaluate their dynamics under anthropogenic impact. The wilting point and the dependence of the capillary-sorption and total water potentials of the soil water content were determined in laboratory experiments with natural and artificially saline soil samples to evaluate the effect of salt antifreeze substances on water availability for plants under conditions of active application of deicing reagents. Seasonal dynamics of these parameters were investigated. It was found that electrolytes display a steady tendency for the accumulation and redistribution in the root zone rather than for their deep leaching despite humid climatic conditions in Moscow megalopolis. In summer, regular droughts result in drying of the root zone to critical values and to the concentration of electrolytes up to the values that make the total water potential of soil unsuitable for water uptake by roots. The key factor of soil degradation under the impact of electrolytes is the soil dispersity: the finer the texture, the higher the soil salinization and solonetzicity and the stronger irreversible changes in the soil water retention capacity and physical properties.

Physical Property Modeling of Concentrated Cesium Eluate Solutions, Part I - Derivation of Models

Energy Technology Data Exchange (ETDEWEB)

Choi, A.S.; Pierce, R. A.; Edwards, T. B.; Calloway, T. B.

2005-09-15

Major analytes projected to be present in the Hanford Waste Treatment Plant cesium ion-exchange eluate solutions were identified from the available analytical data collected during radioactive bench-scale runs, and a test matrix of cesium eluate solutions was designed within the bounding concentrations of those analytes. A computer model simulating the semi-batch evaporation of cesium eluate solutions was run in conjunction with a multi-electrolyte aqueous system database to calculate the physical properties of each test matrix solution concentrated to the target endpoints of 80% and 100% saturation. The calculated physical properties were analyzed statistically and fitted into mathematical expressions for the bulk solubility, density, viscosity, heat capacity and volume reduction factor as a function of temperature and concentration of each major analyte in the eluate feed. The R{sup 2} of the resulting physical property models ranged from 0.89 to 0.99.

Effect of Dehydration Conditions on the Chemical, Physical, and Rehydration Properties of Instant Whole Bean (Phaseolus vulgaris L. var. Azufrado

Directory of Open Access Journals (Sweden)

Juan Alberto Resendiz Vazquez

2015-01-01

Full Text Available The purpose of this study was to evaluate the effect of dehydration conditions on the chemical, physical, and rehydration properties of instant whole beans (Phaseolus vulgaris L. var. Azufrado using a 22 factorial design (air temperature: 25°C and 30°C, air velocity: 0.5 m/s and 1.0 m/s. To determine the kinetic parameters, the rehydration data were fitted to three models: Peleg’s, First Order, and Sigmoid. The protein, fat, and ash contents of the beans were not significantly affected (P>0.05 by the dehydration conditions. Of the 11 physical properties of the instant whole beans, only water activity and splitting were significantly affected by dehydration conditions (P0.05 between the observed and predicted equilibrium moisture contents of the instant whole beans. Regarding the rehydration kinetics for the instant whole beans, the activation energy values ranged from 23.56 kJ/mol to 30.48 kJ/mol, depending on the dehydration conditions. The dehydration conditions had no significant effect (P>0.05 on the rehydration properties of instant whole beans.

Influence of copper nanoparticles on the physical-chemical properties of activated sludge.

Directory of Open Access Journals (Sweden)

Hong Chen

Full Text Available The physical-chemical properties of activated sludge, such as flocculating ability, hydrophobicity, surface charge, settleability, dewaterability and bacteria extracellular polymer substances (EPS, play vital roles in the normal operation of wastewater treatment plants (WWTPs. The nanoparticles released from commercial products will enter WWTPs and can induce potential adverse effects on activated sludge. This paper focused on the effects of copper nanoparticles (CuNPs on these specific physical-chemical properties of activated sludge. It was found that most of these properties were unaffected by the exposure to lower CuNPs concentration (5 ppm, but different observation were made at higher CuNPs concentrations (30 and 50 ppm. At the higher CuNPs concentrations, the sludge surface charge increased and the hydrophobicity decreased, which were attributed to more Cu2+ ions released from the CuNPs. The carbohydrate content of EPS was enhanced to defense the toxicity of CuNPs. The flocculating ability was found to be deteriorated due to the increased cell surface charge, the decreased hydrophobicity, and the damaged cell membrane. The worsened flocculating ability made the sludge flocs more dispersed, which further increased the toxicity of the CuNPs by increasing the availability of the CuNPs to the bacteria present in the sludge. Further investigation indicated that the phosphorus removal efficiency decreased at higher CuNPs concentrations, which was consistent with the deteriorated physical-chemical properties of activated sludge. It seems that the physical-chemical properties can be used as an indicator for determining CuNPs toxicity to the bacteria in activated sludge. This work is important because bacteria toxicity effects to the activated sludge caused by nanoparticles may lead to the deteriorated treatment efficiency of wastewater treatment, and it is therefore necessary to find an easy way to indicate this toxicity.

a comparative study of the physical and mechanical properties

African Journals Online (AJOL)

HP-User

[11] British Standard Institutes, BS EN 1097-6:2000, Tests for mechanical and physical properties of aggregates. Determination of particle density and water absorption, British Standard Institution, London. [12] Adaba, C. S., Agunwamba, J. C., Nwoji, C. U., Onya, O. E.,. Oze, S, “Comparative Cost And Strength Analysis Of.

Effect of physical, chemical and electro-kinetic properties of pumice samples on radiation shielding properties of pumice material

International Nuclear Information System (INIS)

Tapan, Mücip; Yalçın, Zeynel; İçelli, Orhan; Kara, Hüsnü; Orak, Salim; Özvan, Ali; Depci, Tolga

2014-01-01

Highlights: • Radiation shielding properties of pumice materials are studied. • The relationship between physical, chemical and electro-kinetic properties pumice samples is identified. • The photon atomic parameters are important for the absorber peculiarity of the pumices. - Abstract: Pumice has been used in cement, concrete, brick, and ceramic industries as an additive and aggregate material. In this study, some gamma-ray photon absorption parameters such as the total mass attenuation coefficients, effective atomic number and electronic density have been investigated for six different pumice samples. Numerous values of energy related parameters from low energy (1 keV) to high energy (100 MeV) were calculated using WinXCom programme. The relationship between radiation shielding properties of the pumice samples and their physical, chemical and electro-kinetic properties was evaluated using simple regression analysis. Simple regression analysis indicated a strong correlation between photon energy absorption parameters and density and SiO 2 , Fe 2 O 3 , CaO, MgO, TiO 2 content of pumice samples in this study. It is found that photon energy absorption parameters are not related to electro-kinetic properties of pumice samples

Symptoms of exercise dependence and physical activity in students.

Science.gov (United States)

MacLaren, Vance V; Best, Lisa A

2007-12-01

Health professionals recognize the benefits of moderate physical activity and encourage clients to engage in some form of activity on a regular basis. In spite of these recognized benefits, there are growing concerns that some may exercise at levels detrimental to health. The term exercise dependence refers to those individuals whose extreme exercise schedules interfere with their social, occupational, and family lives. The purpose of this study was to examine the relationship between weekly exercise habits and scores on the Exercise Dependence Questionnaire in a sample of undergraduate students (213 women and 79 men). Overall, participants who reported high activity scored higher than those reporting low activity on subscales measuring interference with family and social life, positive reward, withdrawal, exercise for social reasons, exercise for health reasons, and stereotyped behavior.

Isospin-dependent properties of asymmetric nuclear matter in relativistic mean-field models

OpenAIRE

Chen, Lie-Wen; Ko, Che Ming; Li, Bao-An

2007-01-01

Using various relativistic mean-field models, including the nonlinear ones with meson field self-interactions, those with density-dependent meson-nucleon couplings, and the point-coupling models without meson fields, we have studied the isospin-dependent bulk and single-particle properties of asymmetric nuclear matter. In particular, we have determined the density dependence of nuclear symmetry energy from these different relativistic mean-field models and compare the results with the constra...

Thermo-physical properties of silica gel for adsorption desalination cycle

KAUST Repository

Thu, Kyaw; Chakraborty, Anutosh; Saha, Bidyut Baran; Ng, Kim Choon

2013-01-01

Thermo-physical properties, surface characteristics and water vapor uptake capacity are key parameters in the selection of adsorbent for an adsorption desalination (AD) cycle. In the AD cycles, silica gel is used as adsorbent due to their high water vapor uptake capacity, reliability, repeatability and inexpensiveness as compared to other adsorbents. Three types of commercially available silica gels (Type-RD 2560,Type-A5BW and Type-A++) are investigated using a surface characteristic analyzer and their thermo-physical properties are evaluated using several analysis methods. The instrument used in this investigation employs the static volumetric method with liquid Nitrogen at 77 K as the filing fluid. The surface area of each adsorbent is studied using Brunauer-Emmett-Teller (BET) method whilst the pore size distribution (PSD) analysis is conducted with the Non-Local Density Functional Theory (NLDFT). It is observed that the Type-A++ silica gel (granular type) possesses the highest surface area of 863.6 m2/g amongst the three parent silica gels studied. It has a two-maxima or bimodal distribution pattern where the pore diameters are distributed mostly between 10 Å and 30 Å. Water vapor uptake capacity of silica gels are studied with water vapor dosage apparatus and the results show that the Type-A++ silica gel exhibits a highest equilibrium uptake at 537 cm3/g. These thermo-physical properties are essential for the design and the numerical simulation of AD cycles. © 2012 Published by Elsevier Ltd.

Thermo-physical properties of silica gel for adsorption desalination cycle

KAUST Repository

Thu, Kyaw

2013-02-01

Thermo-physical properties, surface characteristics and water vapor uptake capacity are key parameters in the selection of adsorbent for an adsorption desalination (AD) cycle. In the AD cycles, silica gel is used as adsorbent due to their high water vapor uptake capacity, reliability, repeatability and inexpensiveness as compared to other adsorbents. Three types of commercially available silica gels (Type-RD 2560,Type-A5BW and Type-A++) are investigated using a surface characteristic analyzer and their thermo-physical properties are evaluated using several analysis methods. The instrument used in this investigation employs the static volumetric method with liquid Nitrogen at 77 K as the filing fluid. The surface area of each adsorbent is studied using Brunauer-Emmett-Teller (BET) method whilst the pore size distribution (PSD) analysis is conducted with the Non-Local Density Functional Theory (NLDFT). It is observed that the Type-A++ silica gel (granular type) possesses the highest surface area of 863.6 m2/g amongst the three parent silica gels studied. It has a two-maxima or bimodal distribution pattern where the pore diameters are distributed mostly between 10 Å and 30 Å. Water vapor uptake capacity of silica gels are studied with water vapor dosage apparatus and the results show that the Type-A++ silica gel exhibits a highest equilibrium uptake at 537 cm3/g. These thermo-physical properties are essential for the design and the numerical simulation of AD cycles. © 2012 Published by Elsevier Ltd.

Compositional dependence of physical properties in Se-Sb-In glassy system

Energy Technology Data Exchange (ETDEWEB)

Sharma, Shaveta, E-mail: shaveta.sharma1987@yahoo.com; Sharma, Rita; Kumar, Praveen; Chander, Ravi; Thangaraj, R.; Mian, M. [Semiconductors Laboratory, Department of Physics, GND University, Amritsar (India)

2015-08-28

The growing interest in the investigation of the properties of chalcogenide glasses stems from their potential application as phase change recording media and photoconductive elements in solid state devices.In the present work, the different theoretical parameters viz. coordination number, constraints, number of lone pair electrons, bond energy, heat of atomization, mean bond energy and glass transition temperature for Se{sub 75-x}Sb{sub 25}In{sub x} (x= 0, 1, 3, 5, 7, 9, 11) chalcogenide system have been calculated and their composition variation has been discussed. It has been found that average heat of atomization increases with In content. The glass transition temperature and mean bond energy increases with In. An attempt has been made to explain the varying trend of various parameters with increasing In content.

Physical Properties of Kepler's Super-Earths

Science.gov (United States)

Sasselov, Dimitar D.; Kepler Science Team

2011-01-01

Planets in the radius range from about 1.25 to 2 Re, referred to as Super-Earth-sized planets, do not exist in our Solar System. Their physical properties as determined by theoretical modeling are expected to differ in many ways from our Solar System experience. The Kepler Mission is going to discover many such planets and determine their orbits and radii. For some of them follow-up observations may determine masses, and for a few of them asteroseismology of their stars from the Kepler light curve may determine an age. I will discuss theoretical models for such planets and how they could be constrained by the anticipated Kepler Mission observations.

Strain-dependence of the structure and ferroic properties of epitaxial Ni1−xTi1−yO3 thin films grown on sapphire substrates

International Nuclear Information System (INIS)

Varga, Tamas; Droubay, Timothy C.; Bowden, Mark E.; Stephens, Sean A.; Manandhar, Sandeep; Shutthanandan, Vaithiyalingam; Colby, Robert J.; Hu, Dehong; Shelton, William A.; Chambers, Scott A.

2015-01-01

Polarization-induced weak ferromagnetism has been predicted a few years back in compounds MTiO 3 (M = Fe, Mn, Ni) (Fennie, 2008). We set out to stabilize this metastable, distorted perovskite structure by growing NiTiO 3 epitaxially on sapphire Al 2 O 3 (001) substrate, and to control the polar and magnetic properties via strain. Epitaxial Ni 1−x Ti 1−y O 3 films of different Ni/Ti ratios and thicknesses were deposited on Al 2 O 3 substrates by pulsed laser deposition at different temperatures, and characterized using several techniques. The effect of film thickness, deposition temperature, and film stoichiometry on lattice strain, film structure, and physical properties was investigated. Our structural data from x-ray diffraction, electron microscopy, and x-ray absorption spectroscopy shows that substrate-induced strain has a marked effect on the structure and crystalline quality of the films. Physical property measurements reveal a dependence of the Néel transition and lattice polarization on strain, and highlight our ability to control the ferroic properties in NiTiO 3 thin films by film stoichiometry and thickness. - Highlights: • NiTiO 3 epitaxial thin films with LiNbO 3 -type structure by pulsed laser deposition. • Strain varied by film thickness, stoichiometry, and synthesis temperature. • Systematic study of the effect of strain on film structure and physical properties. • Manipulation of ferroic properties by strain confirmed

Temperature dependent thermoelectric properties of chemically derived gallium zinc oxide thin films

KAUST Repository

Barasheed, Abeer Z.; Sarath Kumar, S. R.; Alshareef, Husam N.

2013-01-01

In this study, the temperature dependent thermoelectric properties of sol-gel prepared ZnO and 3% Ga-doped ZnO (GZO) thin films have been explored. The power factor of GZO films, as compared to ZnO, is improved by nearly 17% at high temperature. A stabilization anneal, prior to thermoelectric measurements, in a strongly reducing Ar/H2 (95/5) atmosphere at 500°C was found to effectively stabilize the chemically derived films, practically eliminating hysteresis during thermoelectric measurements. Subtle changes in the thermoelectric properties of stabilized films have been correlated to oxygen vacancies and excitonic levels that are known to exist in ZnO-based thin films. The role of Ga dopants and defects, formed upon annealing, in driving the observed complex temperature dependence of the thermoelectric properties is discussed. © The Royal Society of Chemistry 2013.

Physical property of disordered-GaAs produced by ion implantation

International Nuclear Information System (INIS)

Nojima, Shunji

1979-01-01

The properties of disordered-GaAs produced by ion implantation and its annealing behaviors are investigated for ion species of H, Be, P, and As, from the viewpoints of both the electrical property and the physical structure of the disordered layer. From the study of the electron diffraction for implanted layers and of the conductivity due to defects as a function of dose, depth, measuring temperature, and annealing temperature, the following two facts are clarified: first, the conductivity due to defects can be a good measure for the degree of disorder in GaAs produced by ion implantation, when it is less than --1 Ω -1 cm -1 . Second, the localized states originating from defects are distributed with the same density in the high dose implanted layer, in spite of the degree of disorder in the physical structure. (author)

Investigation of a piezoelectric droplet delivery method for fuel injection and physical property evaluation

Science.gov (United States)

Zhao, Wei; Menon, Shyam

2017-11-01

A piezoelectric droplet generator is investigated to deliver liquid hydrocarbon fuels to a micro-combustor application. Besides fuel delivery, the setup is intended to measure fuel physical properties such as viscosity and surface tension. These properties are highly relevant to spray generation in internal combustion engines. Accordingly, a drop-on-demand piezoelectric dispenser is used to generate fuel droplet trains, which are studied using imaging and Phase Doppler Particle Anemometry (PDPA). The diagnostics provide information regarding droplet size and velocity and their evolution over time. The measurements are correlated with results from one-dimensional (1D) models that incorporate sub-models for piezo-electric actuation and droplet vaporization. By validating the 1D models for fuels with known physical properties, a technique is developed that has the capability to meter low-vapor pressure liquid fuels to the microcombustor and use information from the droplet train to calculate physical properties of novel fuels.

Physical, sensory and chemical properties of bread prepared from ...

African Journals Online (AJOL)

Physical, sensory and chemical properties of bread prepared from wheat and ... Different levels (0, 1, 2 and 3% w/w) of cissus gum powder was added to ... flours for bread making where 100% wheat bread without cissus gum served as control. ... serve as a gluten substitute in preparing acceptable wheat bread substituted ...

determination of some physical properties of three groundnut varieties

African Journals Online (AJOL)

Dr Obe

groundnuts. Three varieties of groundnuts namely ICGV-SM-93523, RMP-9 and RMP- 12 were collected and some of the physical properties, such as weight, angle of repose, coefficient of friction, bulk density, size, shape and moisture content were determined. The angle of repose for the three varieties was found to range ...

HYDRAULIC AND PHYSICAL PROPERTIES OF SALTSTONE GROUTS AND VAULT CONCRETES

International Nuclear Information System (INIS)

Dixon, K.; Harbour, J.; Phifer, M.

2008-01-01

The Saltstone Disposal Facility (SDF), located in the Z-Area of the Savannah River Site (SRS), is used for the disposal of low-level radioactive salt solution. The SDF currently contains two vaults: Vault 1 (6 cells) and Vault 4 (12 cells). Additional disposal cells are currently in the design phase. The individual cells of the saltstone facility are filled with saltstone. Saltstone is produced by mixing the low-level radioactive salt solution, with blast furnace slag, fly ash, and cement (dry premix) to form a dense, micro-porous, monolithic, low-level radioactive waste form. The saltstone is pumped into the disposal cells where it subsequently solidifies. Significant effort has been undertaken to accurately model the movement of water and contaminants through the facility. Key to this effort is an accurate understanding of the hydraulic and physical properties of the solidified saltstone. To date, limited testing has been conducted to characterize the saltstone. The primary focus of this task was to estimate the hydraulic and physical properties of three types of saltstone and two vault concretes. The saltstone formulations included saltstone premix batched with (1) Deliquification, Dissolution, and Adjustment (DDA) salt simulant (w/pm 0.60), (2) Actinide Removal Process (ARP)/Modular Caustic Side Solvent Extraction Unit (MCU) salt simulant (w/pm 0.60), and (3) Salt Waste Processing Facility (SWPF) salt simulant (w/pm 0.60). The vault concrete formulations tested included the Vault 1/4 concrete and two variations of the Vault 2 concrete (Mix 1 and Mix 2). Wet properties measured for the saltstone formulations included yield stress, plastic viscosity, wet unit weight, bleed water volume, gel time, set time, and heat of hydration. Hydraulic and physical properties measured on the cured saltstone and concrete samples included saturated hydraulic conductivity, moisture retention, compressive strength, porosity, particle density, and dry bulk density. These properties

Physical and chemical properties of pyrethroids.

Science.gov (United States)

Laskowski, Dennis A

2002-01-01

The physical and chemical properties of the pyrethroids bifenthrin, cyfluthrin, cypermethrin (also zetacypermethrin), deltamethrin, esfenvalerate (also fenvalerate), fenpropathrin, lambda-cyhalothrin (also cyhalothrin), permethrin, and tralomethrin have been reviewed and summarized in this paper. Physical properties included molecular weight, octanol-water partition coefficient, vapor pressure, water solubility, Henry's law constant, fish biocencentration factor, and soil sorption, desorption, and Freundlich coefficients. Chemical properties included rates of degradation in water as a result of hydrolysis, photodecomposition, aerobic or anaerobic degradation by microorganisms in the absence of light, and also rates of degradation in soil incubated under aerobic or anaerobic conditions. Collectively, the pyrethroids display a highly nonpolar nature of low water solubility, low volatility, high octanol-water partition coefficients, and have high affinity for soil and sediment particulate matter. Pyrethroids have low mobility in soil and are sorbed strongly to the sediments of natural water systems. Although attracted to living organisms because of their nonpolar nature, their capability to bioconcentrate is mitigated by their metabolism and subsequent elimination by the organisms. In fish, bioconcentration factors (BCF) ranged from 360 and 6000. Pyrethroids in water solution tend to be stable at acid and neutral pH but [table: see text] become increasingly susceptible to hydrolysis at pH values beyond neutral. Exceptions at higher pH are bifenthrin (stable), esfenvalerate (stable), and permethrin (half-life, 240 d). Pyrethroids vary in susceptibility to sunlight. Cyfluthrin and tralomethrin in water had half-lives of 0.67 and 2.5 d; lambda-cyhalothrin, esfenvalerate, deltamethrin, permethrin, and cypermethrin were intermediate with a range of 17-110 d; and bifenthrin and fenpropathrin showed the least susceptibility with half-lives of 400 and 600 d, respectively

Novel instrument for characterizing comprehensive physical properties under multi-mechanical loads and multi-physical field coupling conditions

Science.gov (United States)

Liu, Changyi; Zhao, Hongwei; Ma, Zhichao; Qiao, Yuansen; Hong, Kun; Ren, Zhuang; Zhang, Jianhai; Pei, Yongmao; Ren, Luquan

2018-02-01

Functional materials represented by ferromagnetics and ferroelectrics are widely used in advanced sensor and precision actuation due to their special characterization under coupling interactions of complex loads and external physical fields. However, the conventional devices for material characterization can only provide a limited type of loads and physical fields and cannot simulate the actual service conditions of materials. A multi-field coupling instrument for characterization has been designed and implemented to overcome this barrier and measure the comprehensive physical properties under complex service conditions. The testing forms include tension, compression, bending, torsion, and fatigue in mechanical loads, as well as different external physical fields, including electric, magnetic, and thermal fields. In order to offer a variety of information to reveal mechanical damage or deformation forms, a series of measurement methods at the microscale are integrated with the instrument including an indentation unit and in situ microimaging module. Finally, several coupling experiments which cover all the loading and measurement functions of the instrument have been implemented. The results illustrate the functions and characteristics of the instrument and then reveal the variety in mechanical and electromagnetic properties of the piezoelectric transducer ceramic, TbDyFe alloy, and carbon fiber reinforced polymer under coupling conditions.

Physical properties and fiber dimension in Stem, Branch and root of Alder Wood

OpenAIRE

Moya-Roque, Roger; Kiaei, Majid

2015-01-01

The aim of this study was to determine physical properties and fiber dimensions in stem, branch and root wood for alder (Alnus glutinosa L) species. For this purpose, three normal alder trees were selected from Khanican forest in north of Iran. Disks were taken from three parts such as stem, branch and root of trees. Testing samples were randomly taken at disk surfaces to examine the physical properties (according to the ISO standard for oven-dry density and volumetric shrinkage) and fiber di...

Toxicity and physical properties of atrazine and its degradation products: A literature survey

Energy Technology Data Exchange (ETDEWEB)

Pugh, K.C.

1994-10-01

The Tennessee Valley Authority`s Environmental Research Center has been developing a means of detoxifying atrazine waste waters using TiO{sub 2} photocatalysis. The toxicity and physical properties of atrazine and its degradation products will probably be required information in obtaining permits from the United States Environmental Protection Agency for the demonstration of any photocatalytic treatment of atrazine waste waters. The following report is a literature survey of the toxicological and physical properties of atrazine and its degradation products.

Spectral properties and lattice-size dependences in cluster algorithms

OpenAIRE

Kerler, W.

1993-01-01

Simulation results of Ising systems for several update rules, observables, and dimensions are analyzed. The lattice-size dependence is discussed for the autocorrelation times and for the weights of eigenvalues, giving fit results in the case of power laws. Implications of spectral properties are pointed out and the behavior of a particular observable not governed by detailed balance is explained.

Optical properties of Al nanostructures from time dependent density functional theory

KAUST Repository

Mokkath, Junais Habeeb; Schwingenschlö gl, Udo

2016-01-01

The optical properties of Al nanostructures are investigated by means of time dependent density functional theory, considering chains of varying length and ladders/stripes of varying aspect ratio. The absorption spectra show redshifting

Long-Term Effects of Legacy Copper Contamination on Microbial Activity and Soil Physical Properties

DEFF Research Database (Denmark)

Arthur, Emmanuel; Møldrup, Per; Holmstrup, Martin

Soils heavily contaminated with copper (Cu) are considered unsuitable for agricultural use due to adverse impacts on microbial activity, soil physical properties, and direct toxicity to crops. This study investigated effects of Cu pollution from timber preservation activities between 1911 and 1924...... on soil micro-organisms and subsequent effects on physical properties of a sandy loam soil. Tillage operations over the last 70 years have caused spreading of the initially localized contamination and have created a Cu concentration gradient from 20 to 3800 mg kg-1 across an agricultural field in Hygum......, Denmark. Soil samples obtained from the fallow field were used to determine total microbial activity using fluorescein diacetate and dehydrogenase assays. The physical properties measured included water-dispersible clay, bulk density, air permeability and air-filled porosity. Significant differences...

Morphine Tolerance and Physical Dependence Are Altered in Conditional HIV-1 Tat Transgenic Mice.

Science.gov (United States)

Fitting, Sylvia; Stevens, David L; Khan, Fayez A; Scoggins, Krista L; Enga, Rachel M; Beardsley, Patrick M; Knapp, Pamela E; Dewey, William L; Hauser, Kurt F

2016-01-01

Despite considerable evidence that chronic opiate use selectively affects the pathophysiologic consequences of human immunodeficiency virus type 1 (HIV-1) infection in the nervous system, few studies have examined whether neuro-acquired immune deficiency syndrome (neuroAIDS) might intrinsically alter the pharmacologic responses to chronic opiate exposure. This is an important matter because HIV-1 and opiate abuse are interrelated epidemics, and HIV-1 patients are often prescribed opiates as a treatment of HIV-1-related neuropathic pain. Tolerance and physical dependence are inevitable consequences of frequent and repeated administration of morphine. In the present study, mice expressing HIV-1 Tat in a doxycycline (DOX)-inducible manner [Tat(+)], their Tat(-) controls, and control C57BL/6 mice were chronically exposed to placebo or 75-mg morphine pellets to explore the effects of Tat induction on morphine tolerance and dependence. Antinociceptive tolerance and locomotor activity tolerance were assessed using tail-flick and locomotor activity assays, respectively, and physical dependence was measured with the platform-jumping assay and recording of other withdrawal signs. We found that Tat(+) mice treated with DOX [Tat(+)/DOX] developed an increased tolerance in the tail-flick assay compared with control Tat(-)/DOX and/or C57/DOX mice. Equivalent tolerance was developed in all mice when assessed by locomotor activity. Further, Tat(+)/DOX mice expressed reduced levels of physical dependence to chronic morphine exposure after a 1-mg/kg naloxone challenge compared with control Tat(-)/DOX and/or C57/DOX mice. Assuming the results seen in Tat transgenic mice can be generalized to neuroAIDS, our findings suggest that HIV-1-infected individuals may display heightened analgesic tolerance to similar doses of opiates compared with uninfected individuals and show fewer symptoms of physical dependence. Copyright © 2015 by The American Society for Pharmacology and Experimental

Global properties of physically interesting Lorentzian spacetimes

Science.gov (United States)

Nawarajan, Deloshan; Visser, Matt

Under normal circumstances most members of the general relativity community focus almost exclusively on the local properties of spacetime, such as the locally Euclidean structure of the manifold and the Lorentzian signature of the metric tensor. When combined with the classical Einstein field equations this gives an extremely successful empirical model of classical gravity and classical matter — at least as long as one does not ask too many awkward questions about global issues, (such as global topology and global causal structure). We feel however that this is a tactical error — even without invoking full-fledged “quantum gravity” we know that the standard model of particle physics is also an extremely good representation of some parts of empirical reality; and we had better be able to carry over all the good features of the standard model of particle physics — at least into the realm of semi-classical quantum gravity. Doing so gives us some interesting global features that spacetime should possess: On physical grounds spacetime should be space-orientable, time-orientable, and spacetime-orientable, and it should possess a globally defined tetrad (vierbein, or in general a globally defined vielbein/n-bein). So on physical grounds spacetime should be parallelizable. This strongly suggests that the metric is not the fundamental physical quantity; a very good case can be made for the tetrad being more fundamental than the metric. Furthermore, a globally-defined “almost complex structure” is almost unavoidable. Ideas along these lines have previously been mooted, but much is buried in the pre-arXiv literature and is either forgotten or inaccessible. We shall revisit these ideas taking a perspective very much based on empirical physical observation.

The physical and chemical properties of uranium hexafluoride

International Nuclear Information System (INIS)

Barber, E.J.

1988-01-01

This paper describes what uranium hexafluoride (UF 6 ) is, gives some of its pertinent physical properties, illustrates significant reactions between UF 6 and other substances, touches on its toxic properties, and states some of the ''do's'' and ''don't's'' of UF 6 handling. The properties of UF 6 determine how it must be handled and make direct observation impossible. To determine that the material in a container is UF 6 , one must use other instruments in addition to a scale. Because of the very large volume expanision of UF 6 upon melting, diligence must be exercised in filling cylinders in which the UF 6 is partially solidified. A cylinder of liquified UF 6 with no ullage is potentially the equivalent of a superheated hot water heater, not just a hydraulically overpressurized cylinder. Finally, UF 6 can be handled safely by careful attention to the suggested precautions. 9 refs., 2 tabs., 3 figs

HYDRAULIC AND PHYSICAL PROPERTIES OF MCU SALTSTONE

International Nuclear Information System (INIS)

Dixon, K; Mark Phifer, M

2008-01-01

The Saltstone Disposal Facility (SDF), located in the Z-Area of the Savannah River Site (SRS), is used for the disposal of low-level radioactive salt solution. The SDF currently contains two vaults: Vault 1 (6 cells) and Vault 4 (12 cells). Additional disposal cells are currently in the design phase. The individual cells of the saltstone facility are filled with saltstone., Saltstone is produced by mixing the low-level radioactive salt solution, with blast furnace slag, fly ash, and cement or lime to form a dense, micro-porous, monolithic, low-level radioactive waste form. The saltstone is pumped into the disposal cells where it subsequently solidifies. Significant effort has been undertaken to accurately model the movement of water and contaminants through the facility. Key to this effort is an accurate understanding of the hydraulic and physical properties of the solidified saltstone. To date, limited testing has been conducted to characterize the saltstone. The primary focus of this task was to estimate the hydraulic and physical properties of MCU (Modular Caustic Side Solvent Extraction Unit) saltstone relative to two permeating fluids. These fluids included simulated groundwater equilibrated with vault concrete and simulated saltstone pore fluid. Samples of the MCU saltstone were prepared by the Savannah River National Laboratory (SRNL) and allowed to cure for twenty eight days prior to testing. These samples included two three-inch diameter by six inch long mold samples and three one-inch diameter by twelve inch long mold samples

HYDRAULIC AND PHYSICAL PROPERTIES OF MCU SALTSTONE

Energy Technology Data Exchange (ETDEWEB)

Dixon, K; Mark Phifer, M

2008-03-19

The Saltstone Disposal Facility (SDF), located in the Z-Area of the Savannah River Site (SRS), is used for the disposal of low-level radioactive salt solution. The SDF currently contains two vaults: Vault 1 (6 cells) and Vault 4 (12 cells). Additional disposal cells are currently in the design phase. The individual cells of the saltstone facility are filled with saltstone., Saltstone is produced by mixing the low-level radioactive salt solution, with blast furnace slag, fly ash, and cement or lime to form a dense, micro-porous, monolithic, low-level radioactive waste form. The saltstone is pumped into the disposal cells where it subsequently solidifies. Significant effort has been undertaken to accurately model the movement of water and contaminants through the facility. Key to this effort is an accurate understanding of the hydraulic and physical properties of the solidified saltstone. To date, limited testing has been conducted to characterize the saltstone. The primary focus of this task was to estimate the hydraulic and physical properties of MCU (Modular Caustic Side Solvent Extraction Unit) saltstone relative to two permeating fluids. These fluids included simulated groundwater equilibrated with vault concrete and simulated saltstone pore fluid. Samples of the MCU saltstone were prepared by the Savannah River National Laboratory (SRNL) and allowed to cure for twenty eight days prior to testing. These samples included two three-inch diameter by six inch long mold samples and three one-inch diameter by twelve inch long mold samples.

Physical properties of Zr50Cu40-xAl10Pdx bulk glassy alloys

International Nuclear Information System (INIS)

Wencka, M.; Jagodic, M.; Gradisek, A.; Kocjan, A.; Jaglicic, Z.; McGuiness, P.J.; Apih, T.; Yokoyama, Y.; Dolinsek, J.

2010-01-01

It was shown recently (Yokoyama et al. ) that the addition of a small amount of Pd to the Zr 50 Cu 40 Al 10 bulk glassy alloy (BGA) has a beneficial effect on fatigue-strength enhancement, where the composition Zr 50 Cu 37 Al 10 Pd 3 behaved in a resonant-like way by showing the highest fatigue limit of 1050 MPa and the minimum Vickers hardness. We performed a study of the magnetic properties, the specific heat, the electrical resistivity and the hydrogen-diffusion constant for a series of compositions Zr 50 Cu 40-x Al 10 Pd x (x = 0-7 at.%), in order to determine their physical properties and to check for the influence of the Pd content on these properties. The Zr 50 Cu 40-x Al 10 Pd x BGAs are nonmagnetic, conducting alloys, where the Pauli spin susceptibility of the conduction electrons is the only source of paramagnetism. The low-temperature specific heat indicates an enhancement of the conduction-electron effective mass m* below 5 K, suggesting that the Zr 50 Cu 40-x Al 10 Pd x BGAs are not free-electron-like compounds. The electrical resistivities of the Zr 50 Cu 40-x Al 10 Pd x BGAs amount to about 200 μΩ cm and show a small, negative temperature coefficient (NTC) with an increase from 300 to 2 K of 4%. The hydrogen self-diffusion constant D in hydrogen-loaded samples shows classical over-barrier-hopping temperature dependence and is of comparable magnitude to the related icosahedral and amorphous Zr 69.5 Cu 12 Ni 11 Al 7.5 hydrogen-storage alloys. No correlation between the investigated physical parameters and the Pd content of the samples could be observed.

Measurement of Physical and Hydraulic Properties of Organic Soil Using Computed Tomographic Imagery

Science.gov (United States)

Blais, K. E.; Quinton, W. L.; Heck, R. J.; Price, J. S.; Schmidt, M. G.

2005-12-01

The Lower Liard River valley is located within the continental northern boreal region and the zone of discontinuous permafrost. Lying in the centre of the Mackenzie basin, this valley is an extensive flat headwater region with a high density of open water and peatlands. Several standard methods of measuring the physical properties of organic soils exist, although many of them have several drawbacks that limit their use. Organic soils, in particular, have unique properties that require special attention to ensure that the measured hydrological characteristics are represented as they exist in nature. The goal of this research was to devise an improved method of analyzing and measuring the physical and hydraulic properties of organic soil using MicroCT imagery. Specifically, this research seeks to determine if two and three-dimensional images of peat can be used to accurately characterize air-filled porosity, active porosity, pore size distribution, pore saturated area and capillarity of porous Sphagnum cells. Results indicate that measurements derived from these images are consistent with current literature. They also suggest that this non-destructive method is a valuable tool for measuring peat physical and hydraulic properties and that there is potential for additional research using CT technology.

Short-term visual memory properties sheet secondary school age with different levels of physical development

Directory of Open Access Journals (Sweden)

E.E. Menshikh

2013-12-01

Full Text Available Purpose . The results presented properties of short-term visual memory with different levels of physical development. Materials and methods. The study included 405 boys and girls Cherkassy school 11 in age from 13 to 16 years. Study of short-term visual memory was carried out using tables with 10 characters ( numbers and ambiguous geometric shapes . Indicator memory was the higher, the more information was displayed. Measured the length and body weight was recorded cardiorespiratory indicators - heart rate at rest and after 20 squats, lung capacity, breath-hold inspiration and expiration. Physical development factor was calculated by taking into account actual and average population indices. Results . Found that the volume of short-term visual memory, the boys and girls high school age does not depend on the level of their physical development. Despite the fact that the trend towards higher performance memory in groups of persons with a high level of physical development compared to their same age with medium and low levels, significant differences between the mean values for the most part have been identified. No significant differences between the values of the investigated cognitive function in groups by sex. Conclusions . Growth pattern memory with age in this period of ontogenesis preserved that coincides with the data presented in the scientific works of scientists.

Structural and topological aspects of borophosphate glasses and their relation to physical properties

DEFF Research Database (Denmark)

Hermansen, Christian; Youngman, R.E.; Wang, J.

2015-01-01

We establish a topological model of alkali borophosphate and calcium borophosphate glasses that describes both the effect of the network formers and network modifiers on physical properties. We show that the glass transition temperature (Tg), Vickers hardness (HV), liquid fragility (m) and isobaric....... The origin of the effect of the type of network modifying oxide on Tg, HV, m and ΔCp of calcium borophosphate glasses is revealed in terms of the modifying ion sub-network. The same topological principles quantitatively explain the significant differences in physical properties between the alkali...... and the calcium borophosphate glasses. This work has implications for quantifying structure-property relations in complex glass forming systems containing several types of network forming and modifying oxides....

Exercise dependence score in patients with longstanding eating disorders and controls: the importance of affect regulation and physical activity intensity.

Science.gov (United States)

Bratland-Sanda, Solfrid; Martinsen, Egil W; Rosenvinge, Jan H; Rø, Oyvind; Hoffart, Asle; Sundgot-Borgen, Jorunn

2011-01-01

To examine associations among exercise dependence score, amount of physical activity and eating disorder (ED) symptoms in patients with longstanding ED and non-clinical controls. Adult female inpatients (n = 59) and 53 age-matched controls participated in this cross sectional study. Assessments included the eating disorders examination, eating disorders inventory, exercise dependence scale, reasons for exercise inventory, and MTI Actigraph accelerometer. Positive associations were found among vigorous, not moderate, physical activity, exercise dependence score and ED symptoms in patients. In the controls, ED symptoms were negatively associated with vigorous physical activity and not correlated with exercise dependence score. Exercise for negative affect regulation, not weight/appearance, and amount of vigorous physical activity were explanatory variables for exercise dependence score in both groups. The positive associations among exercise dependence score, vigorous physical activity and ED symptoms need proper attention in the treatment of longstanding ED. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.

Hypoxia alters the physical properties of the tumor microenvironment

Science.gov (United States)

Gilkes, Daniele

Of all the deaths attributed to cancer, 90% are due to metastasis, or the spread of cancer cells from a primary tumor to distant organs, and treatments that prevent or cure metastasis remain elusive. Emerging data indicate that low oxygen states within a tumor, termed hypoxia, can alter the chemical and physical parameters of the extracellular matrix (ECM), or scaffold of the tumor tissue. These changes generate a microenvironment that may be more conducive for promoting metastasis. During tumor evolution, changes in the composition and the overall content of the ECM reflect both its biophysical and biological properties and these strongly influence the cells properties, such as cellular proliferation and cell motility. The talk will cover how hypoxia arises within normal tissue and also in tumors. We will cover the role of hypoxia in collagen biogenesis which influences compositional changes to the tumor microenvironment and discuss how these changes lead to a stiffer tumor stroma. The challenges in determining the influence of chemical versus physical cues on cancer progression will also be considered.

Lithium doped calcium phosphate cement maintains physical mechanical properties and promotes osteoblast proliferation and differentiation.

Science.gov (United States)

Li, Li; Wang, Renchong; Li, Baichuan; Liang, Wei; Pan, Haobo; Cui, Xu; Tang, Jingli; Li, Bing

2017-07-01

Calcium phosphate cement (CPC) has been widely used in bone tissue repairing due to its physical mechanical properties and biocompatibility. Addition of trace element to CPC has shown promising evidence to improve the physical properties and biological activities of CPC. Lithium (Li) has effect on osteoblast proliferation and differentiation. In this study, we incorporated Li to CPC and examined the physical properties of Li/CPC and its effect on osteoblast proliferation and differentiation. We found that Li doped CPC maintained similar setting time, pore size distribution, compressive strength, composition, and morphology as CPC without Li. Additionally, Li doped CPC improved osteoblast proliferation and differentiation significantly compared to CPC without Li. To our knowledge, our results, for the first time, show that Li doped CPC has beneficial effect on osteoblast in cell culture while keeps the excellent physical-mechanical properties of CPC. This study will lead to potential application of Li doped CPC in bone tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 944-952, 2017. © 2016 Wiley Periodicals, Inc.

Physical properties of the tetragonal CuMnAs: A first-principles study

Czech Academy of Sciences Publication Activity Database

Máca, František; Kudrnovský, Josef; Drchal, Václav; Carva, K.; Baláž, P.; Turek, I.

2017-01-01

Roč. 96, č. 9 (2017), s. 1-8, č. článku 094406. ISSN 2469-9950 R&D Projects: GA ČR GB14-37427G Grant - others:GA MŠk(CZ) LM2015042 Institutional support: RVO:68378271 Keywords : first-principles calculations * defects * CuMnAs * transport properties Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 3.836, year: 2016

Physical and mechanical properties of self-compacting concrete containing superplasticizer and metakaolin

Science.gov (United States)

Shahidan, Shahiron; Tayeh, Bassam A.; Jamaludin, A. A.; Bahari, N. A. A. S.; Mohd, S. S.; Zuki Ali, N.; Khalid, F. S.

2017-11-01

The development of concrete technology shows a variety of admixtures in concrete to produce special concrete. This includes the production of self-compacting concrete which is able to fill up all spaces, take formwork shapes and pass through congested reinforcement bars without vibrating or needing any external energy. In this study, the main objective is to compare the physical and mechanical properties of self-compacting concrete containing metakaolin with normal concrete. Four types of samples were produced to study the effect of metakaolin towards the physical and mechanical properties of self-compacting concrete where 0%, 5%, 10% and 15% of metakaolin were used as cement replacement. The physical properties were investigated using slump test for normal concrete and slump flow test for self-compacting concrete. The mechanical properties were tested for compressive strength and tensile strength. The findings of this study show that the inclusion of metakaolin as cement replacement can increase both compressive and tensile strength compared to normal concrete. The highest compressive strength was found in self-compacting concrete with 15% metakaolin replacement at 53.3 MPa while self-compacting concrete with 10% metakaolin replacement showed the highest tensile strength at 3.6 MPa. On top of that, the finishing or concrete surface of both cube and cylinder samples made of self-compacting concrete produced a smooth surface with the appearance of less honeycombs compared to normal concrete.

Physical properties of charged particle beams for use in radiotherapy

International Nuclear Information System (INIS)

Knapp, E.A.

1975-01-01

The physical properties of the possible charged particle beams used for cancer radiotherapy are reviewed. Each property is discussed for all interesting particles (π, p, α, Ne ion) and the differences are emphasized. This is followed by a short discussion of the several beam delivery systems used in particle therapy today, emphasizing the differences in the problems for the several different radiations, particularly the differences between the accelerated particle beams and those of a secondary nature. Dose calculation techniques are described

Thermo-physical Properties and Mechanical Properties of Burn-resistant Titanium Alloy Ti40

Directory of Open Access Journals (Sweden)

LAI Yunjin

2017-10-01

Full Text Available As a functional material of burn-resistant titanium alloy, the physical properties of Ti40 alloy were first reported. The chemical compositions of Ti40 alloy ingots by VAR were uniform. The microstructures of Ti40 alloy slab manufactured by HEFF+WPF were uniform. The results show that the room temperature tensile strength of Ti40 alloy is 950 MPa degree. The properties of high temperature heat exposure, creep resistance and lasting time are good at 500 ℃. In the range from room temperature to 600 ℃, Young's modulus and shear modulus are decreased linearly with increasing the temperature, Poisson's ratio is increases slowly as the temperature rises, and linear thermal expansion coefficient and average linear expansion coefficient is increase as the temperature rises.

Physical properties and organic carbon content of a Rhodic Kandiudox fertilized with pig slurry and poultry litter

Directory of Open Access Journals (Sweden)

Luiz Paulo Rauber

2012-08-01

Full Text Available The impact of pig slurry and poultry litter fertilization on soils depends on the conditions of use and the amounts applied. This study evaluated the effect of organic fertilizers after different application periods in different areas on the physical properties and organic carbon contents of a Rhodic Kandiudox, in Concordia, Santa Catarina, in Southern Brazil. The treatments consisted of different land uses and periods of pig and poultry litter fertilization: silage maize (M7 years, silage maize (M20 years, annual ryegrass pasture (P3 years, annual ryegrass pasture (P15 years, perennial pasture (PP20 years, yerba mate tea (Mt20 years, native forest (NF, and native pasture without manure application (P0. The 0-5, 5-10 and 10-20 cm soil layers were sampled and analyzed for total organic carbon, total nitrogen and soil physical properties such as density, porosity, aggregation, degree of flocculation, and penetration resistance. The organic carbon levels in the cultivated areas treated with organic fertilizer were even lower than in native forest soil. The organic fertilizers and studied management systems reduced the flocculation degree of the clay particles, and low macroporosity was observed in some areas. Despite these changes, a good soil physical structure was maintained, e.g., soil density and resistance to penetration were below the critical limits, whereas aggregate stability was high, which is important to reduce water erosion in these areas with rugged terrain in western Santa Catarina, used for pig and poultry farming.

Modelling time-dependent mechanical behaviour of softwood using deformation kinetics

DEFF Research Database (Denmark)

Engelund, Emil Tang; Svensson, Staffan

2010-01-01

The time-dependent mechanical behaviour (TDMB) of softwood is relevant, e.g., when wood is used as building material where the mechanical properties must be predicted for decades ahead. The established mathematical models should be able to predict the time-dependent behaviour. However, these models...... are not always based on the actual physical processes causing time-dependent behaviour and the physical interpretation of their input parameters is difficult. The present study describes the TDMB of a softwood tissue and its individual tracheids. A model is constructed with a local coordinate system that follows...... macroscopic viscoelasticity, i.e., the time-dependent processes are to a significant degree reversible....

First-guess dependence of a physically based set of temperature-humidity retrievals from HIRS2/MSU data. [High-resolution Infrared Radiation Sounder 2/Microwave Sounding Unit

Science.gov (United States)

Reuter, D.; Susskind, Joel; Pursch, Andrew

1988-01-01

The first-guess dependence of temperature and humidity fields retrieved from HIRS2/MSU data using the GLA (Goddard Laboratory for Atmospheres) physically based retrieval scheme is examined. Retrievals were performed over the ALPEX region for two successive synoptic periods, 1200 UTC March 4 and 00000 UTC March 5, 1982, using three different initial guesses for each period. Results show rather low first-guess dependence for the thickness fields and larger first-guess dependence for the precipitable water fields, especially close to the surface. The humidity retrieval algorithm used is described. The processing system has the property of maintaining the accuracy of a good guess and improving a poor one for both thickness and precipitable water at all levels.

Physical and functional properties of breakfast cereals from maize ...

African Journals Online (AJOL)

The results revealed the following ranges of physical and functional properties; pH (4.70- 6.56), bulk density (0.29 - 0.71g/ml), water absorption capacity (68.31- 76.39%), oil absorption capacity (0.87- 1.32%), foam capacity (2.48- 3.49%), viscosity (19.73-31.08%), gelation temperature (121-157°C), emulsification capacity ...

Some physical and strength properties of immature Pinus patula ...

African Journals Online (AJOL)

A study was conducted to determine physical and strength properties of immature Pinus patula grown in Iringa and Njombe regions of Tanzania. Sample trees aged 5 to 15 years were collected from farmers' woodlots. The trees were categorized into 5 age classes: 5 - 7, 8 - 10, 11 - 12, 13 - 14 and 15 years. Four trees from ...

Effects of oxygen annealing on the physical properties and surface microstructures of La0.8Ba0.2MnO3 films

International Nuclear Information System (INIS)

Murugavel, P; Lee, J H; Lee, K-B; Park, J H; Chung, J-S; Yoon, J-G; Noh, T W

2002-01-01

We have investigated the effects of oxygen annealing on the transport properties and surface microstructures of epitaxial La 0.8 Ba 0.2 MnO 3 (LBMO) films deposited on SrTiO 3 substrate at different oxygen pressures using the pulsed laser deposition technique. The thickness dependence of the transport properties was strongly affected by the oxygen pressure during the deposition and the oxygen annealing temperature. Oxygen stoichiometry, in addition to the substrate-induced strain, was found to be a very important factor in controlling the physical properties of low-doped LBMO. Oxygen annealing seemed to induce strain and the strain accommodated in the films was relaxed by forming a secondary phase in an ordered rod-like shape or in particulate form

Mechanical and Physical Properties of Hydrophobized Lightweight Aggregate Concrete with Sewage Sludge.

Science.gov (United States)

Suchorab, Zbigniew; Barnat-Hunek, Danuta; Franus, Małgorzata; Łagód, Grzegorz

2016-04-27

This article is focused on lightweight aggregate-concrete modified by municipal sewage sludge and lightweight aggregate-concrete obtained from light aggregates. The article presents laboratory examinations of material physical parameters. Water absorptivity of the examined material was decreased by the admixture of water emulsion of reactive polysiloxanes. Water transport properties were determined using Time Domain Reflectometry, an indirect technique for moisture detection in porous media. Together with basic physical parameters, the heat conductivity coefficient λ was determined for both types of lightweight aggregate-concrete. Analysis of moisture and heat properties of the examined materials confirmed the usefulness of light aggregates supplemented with sewage sludge for prospective production.

Frequency and temperature dependence of dielectric properties of chicken meat

Science.gov (United States)

Dielectric properties of chicken breast meat were measured with an open-ended coaxial-line probe between 200 MHz and 20 GHz at temperatures ranging from -20 degree C to +25 degree C. At a given temperature, the frequency dependence of the dielectric constant reveals two relaxations while those of th...

Effect of nanoclay particles on some physical and mechanical properties of soils

Directory of Open Access Journals (Sweden)

H Sharifnasab

2016-04-01

Full Text Available Introduction: As a mechanical tillage practices on soil preparation improve soil structure, increase in porosity, better distribution of soil aggregates and eventually modify the physical properties of soil. The use of nano-technology in agricultural science and its application in tillage for improving the physical properties and mechanical issues has grown substantially. Nanotechnology is an appropriate way to reduce soil limitations. However the nanoparticles are very small amounts in soil, due to features such as high surface area, surface charge (appearance and sometimes porous nano-engineering of physical-chemical properties of soil are affected significantly (Mohammadi & Niazian, 2013. To use of nanomaterials in the territory of a new issue (Taipodia et al., 2011. Small developments on the use of nanoparticles to improve soil quality and land reform have been taken (Theron et al., 2008. Clay soil was used to enhance the compressive strength (Yonekura & Miwa, 1993. Nanosilica particle effects were examined for increasing resistance against penetration and consolidation (Noll et al., 1992. In 2005, these particles were used to increase adhesion and reduce viscosity. It seemed that the adhesion of the particles was depended on Nanosilica (Mohammadi & Niazian, 2013. The use of nanomaterials showed that the increased pH and soil fertility, improved soil physical structure, and reduced mobility, availability and toxicity of heavy metals and other environmental factors and those that will stabilize the soil components and subsides the erosion in the mining pick, (Lal, 2008. In agriculture, the soil conditioner studies have shown that nanoparticles can mine the soil quality by increasing water-holding capacity, increasing silt and clay and improve levels of nutrients, and eliminate toxins, (Liu and Lal, 2012.In this study, the effect on some physical and mechanical properties of soil contain clay gradation, Atterberg limits, specifications

Investigation of the mechanical and physical properties of greywacke specimens

Czech Academy of Sciences Publication Activity Database

Holub, Karel; Konečný, Pavel; Knejzlík, Jaromír

2009-01-01

Roč. 46, č. 1 (2009), s. 188-193 ISSN 1365-1609 Institutional research plan: CEZ:AV0Z30860518 Keywords : greywacke * mechanical and physical properties Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.142, year: 2009 www.elsevier.com/locate ijrmms

Assessment of physical properties of foods commonly consumed by children

Directory of Open Access Journals (Sweden)

G Neeraja

2018-01-01

Conclusion: The physical properties and texture of food can be considered to be a risk factor for evaluating the relationship between food retention and dental caries. This information can further be used as an educative tool to parents and caregivers for effective modification of diet.

Effect of concentration of polyfunctional monomers on physical properties of acrylonitrile-butadiene rubber under electron-beam irradiation

International Nuclear Information System (INIS)

Yasin, T.; Ahmed, S.; Yoshii, F.; Makuuchi, K.

2003-01-01

The effect of concentration of different polyfunctional monomers (PFMs) on the physical properties of electron-beam irradiated acrylonitrile-butadiene rubber (NBR) has been investigated. The PFMs used were diethylene glycol dimethacrylate (2G), tetraethylene glycol dimethacrylate (4G), trimethylol propane triacrylate (A-TMPT), trimethylol propane trimethacrylate (TMPT) and tetramethylol methane tetraacrylate (A-TMMT). The physical properties of EB irradiated NBR sheets were evaluated by measurement of tensile strength, elongation %, hardness and gel fraction etc. The results show a remarkable increase in all physical properties as the concentration of PFMs increases from 1 phr to 5 phr in the NBR samples. The improvement in physical properties of radiation crosslinked NBR in the presence of PFMs may be attributed to its increased crosslinking density as observed by corresponding increase in gel content

Characterization of temperature-dependent optical material properties of polymer powders

Energy Technology Data Exchange (ETDEWEB)

Laumer, Tobias [Bayerisches Laserzentrum GmbH, 91052 Erlangen (Germany); SAOT Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen (Germany); CRC Collaborative Research Center 814 - Additive Manufacturing, 91052 Erlangen (Germany); Stichel, Thomas; Bock, Thomas; Amend, Philipp [Bayerisches Laserzentrum GmbH, 91052 Erlangen (Germany); CRC Collaborative Research Center 814 - Additive Manufacturing, 91052 Erlangen (Germany); Schmidt, Michael [Bayerisches Laserzentrum GmbH, 91052 Erlangen (Germany); University of Erlangen-Nürnberg, Institute of Photonic Technologies, 91052 Erlangen (Germany); SAOT Erlangen Graduate School in Advanced Optical Technologies, 91052 Erlangen (Germany); CRC Collaborative Research Center 814 - Additive Manufacturing, 91052 Erlangen (Germany)

2015-05-22

In former works, the optical material properties of different polymer powders used for Laser Beam Melting (LBM) at room temperature have been analyzed. With a measurement setup using two integration spheres, it was shown that the optical material properties of polymer powders differ significantly due to multiple reflections within the powder compared to solid bodies of the same material. Additionally, the absorption behavior of the single particles shows an important influence on the overall optical material properties, especially the reflectance of the powder bed. Now the setup is modified to allow measurements at higher temperatures. Because crystalline areas of semi-crystalline thermoplastics are mainly responsible for the absorption of the laser radiation, the influence of the temperature increase on the overall optical material properties is analyzed. As material, conventional polyamide 12 and polypropylene as new polymer powder material, is used. By comparing results at room temperature and at higher temperatures towards the melting point, the temperature-dependent optical material properties and their influence on the beam-matter interaction during the process are discussed. It is shown that the phase transition during melting leads to significant changes of the optical material properties of the analyzed powders.

Scale dependence of deuteron electrodisintegration

Science.gov (United States)

More, S. N.; Bogner, S. K.; Furnstahl, R. J.

2017-11-01

Background: Isolating nuclear structure properties from knock-out reactions in a process-independent manner requires a controlled factorization, which is always to some degree scale and scheme dependent. Understanding this dependence is important for robust extractions from experiment, to correctly use the structure information in other processes, and to understand the impact of approximations for both. Purpose: We seek insight into scale dependence by exploring a model calculation of deuteron electrodisintegration, which provides a simple and clean theoretical laboratory. Methods: By considering various kinematic regions of the longitudinal structure function, we can examine how the components—the initial deuteron wave function, the current operator, and the final-state interactions (FSIs)—combine at different scales. We use the similarity renormalization group to evolve each component. Results: When evolved to different resolutions, the ingredients are all modified, but how they combine depends strongly on the kinematic region. In some regions, for example, the FSIs are largely unaffected by evolution, while elsewhere FSIs are greatly reduced. For certain kinematics, the impulse approximation at a high renormalization group resolution gives an intuitive picture in terms of a one-body current breaking up a short-range correlated neutron-proton pair, although FSIs distort this simple picture. With evolution to low resolution, however, the cross section is unchanged but a very different and arguably simpler intuitive picture emerges, with the evolved current efficiently represented at low momentum through derivative expansions or low-rank singular value decompositions. Conclusions: The underlying physics of deuteron electrodisintegration is scale dependent and not just kinematics dependent. As a result, intuition about physics such as the role of short-range correlations or D -state mixing in particular kinematic regimes can be strongly scale dependent

Correlations between Optical, Chemical and Physical Properties ofBiomass Burn Aerosols

Energy Technology Data Exchange (ETDEWEB)

Hopkins, Rebecca J.; Lewis, K.; Desyaterik, Yury; Wang, Z.; Tivanski, Alexei V.; Arnott, W.P.; Laskin, Alexander; Gilles, M.K.

2008-01-29

Aerosols generated from burning different plant fuels were characterized to determine relationships between chemical, optical and physical properties. Single scattering albedo ({omega}) and Angstrom absorption coefficients ({alpha}{sub ap}) were measured using a photoacoustic technique combined with a reciprocal nephelometer. Carbon-to-oxygen atomic ratios, sp{sup 2} hybridization, elemental composition and morphology of individual particles were measured using scanning transmission X-ray microscopy coupled with near-edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS) and scanning electron microscopy with energy dispersion of X-rays (SEM/EDX). Particles were grouped into three categories based on sp2 hybridization and chemical composition. Measured {omega} (0.4-1.0 at 405 nm) and {alpha}{sub ap} (1.0-3.5) values displayed a fuel dependence. The category with sp{sup 2} hybridization >80% had values of {omega} (<0.5) and {alpha}{sub ap} ({approx}1.25) characteristic of light absorbing soot. Other categories with lower sp2 hybridization (20 to 60%) exhibited higher {omega} (>0.8) and {alpha}{sub ap} (1.0 to 3.5) values, indicating increased absorption spectral selectivity.

Some physical properties of the higher borides of molybdenum and tungsten

International Nuclear Information System (INIS)

Koval'chenko, M.S.; Bodrova, L.G.; Nemchenko, V.F.; Kolotun, V.F.

1979-01-01

The temperature dependences of the thermal conductivity, the specific electrical resistance, the thermo-e.m.f. and the magnetic susceptibility, together with the variation of magnetic resistance and of Hall constant with the magnetic field strength at liquid nitrogen temperature and at room temperature, for the higher borides Mo 2 B 5 , MoB 4 , W 2 B 5 and WB 4 were studied. Some features of the physical properties of these metallic borides were established. In contrast with the corresponding metals the higher borides are diamagnetic and the Hall constants are negative. The values of the magnetic susceptibility and the Hall constant are larger for the higher borides than for the low borides. As the temperature increased an inversion of the thermo-e.m.f. sign took place and the signs of the thermo-e.m.f. and the Hall constant are different. The values of the magnetic susceptibility of Mo 2 B 5 , MoB 4 and WB 4 were temperature independent. The electronic structure of the compounds studied is discussed briefly. (Auth.)

The Microstructure and Physical Properties of Incinerated Paper-Cullet-Clay Ceramics

Science.gov (United States)

Sahar, M. R.; Hamzah, K.; Rohani, M. S.; Samah, K. A.; Razi, M. M.

A series of ceramic based on (x) incinerated recycle paper - (80-x) cullet - 20 Kaolin clay (where 10×45 wt%) has successfully been made by slip casting technique followed by sintering at 1000 °C. The actual composition of ceramic is analyzed using Energy Dispersive of X-Ray (EDAX) while the phase existence is determined using X-Ray Diffraction (XRD) technique. Their microstructural morphology is observed under Scanning Electron Microscope (SEM) and the physical properties are measured in term of their thermal shrinkage and hardness. It is found that the ceramic contain mostly of Silica and the phase is dominated by the existence of Quartz (SiO2), Wollastonite (CaSiO3) and Anorthite (Ca(Al2SiO8)). The SEM micrograph shows that the morphology is dominated by the existence of granular structure, and then become smoother as the cullet level is further increased. It is also found out that the thermal shrinkage is in the range 18% - 6.5% while the hardness is in the range of 152MPa- 1.463 GPa depending on composition.

Optical and Physical Properties of ONP Deinked Pulp

Directory of Open Access Journals (Sweden)

Iman Akbarpoor

2012-01-01

Full Text Available Enzymes are protein molecules with complex structures that accelerate the biochemical reactions. Activity of these chemical compounds is accomplished at limited range of pH, temperature and concentration. In this study, the effects of different concentrations of cellulose enzyme were investigated on deinking of old newsprint. Old newsprint (ONP was repulped at 5% consistency for 10 minutes in disintegrator with total revolution number of 26500. Enzymatic treatments of recycled ONP pulp were done under constant conditions (10% consistency,treatment time of 15 minutes, pH range of 5-5.5 at different cellulose concentrations of 0.025, 0.05, 0.1 and 0.2% (based on oven-dry waste paper. The optical and physical properties of the standard paper (60g/m2 made at different concentrations of cellulose were evaluated in comparison with control pulp (untreated ONP pulp with cellulase. Overall, the results achieved by comparison the optical properties of the paper produced indicated that using cellulase in deinking of ONP led to increase the brightness and the yellowness and decrease the opacity. The brightness was improved to a maximum level of 47.5 ISO %, but the yellowness was decreased to a minimum level of 11.3 ISO %, while the brightness reduced and the yellowness increased at higher concentrations than 0.05% cellulase. The highest opacity of 99.3 ISO % was achieved using 0.1% cellulase even higher than control pulp. The results gained by comparison the physical properties of the paper showed that using cellulase resulted in decrease of paper calliper, air resistance and density and improve the freeness of pulp

Physical properties of some Sn-based melts

Directory of Open Access Journals (Sweden)

Ilinykh N.

2011-05-01

Full Text Available The physical properties (viscosity, density, electroresistivity and magnetic susceptibility of pure tin, copper, silver, some binary (Sn - Ag, Sn - Cu, Sn - Bi, Sn - Zn and ternary (Sn-Ag-Cu, Sn-BiAg, Sn-Bi-Zn alloys with near eutectic compositions are investigated in wide temperature ranges. The irreversible decrease of viscosity in pure tin melt is discovered at 820 °С during heating. The similar anomaly with the following hysteresis of dynamic viscosity was fixed for binary and ternary alloys but at higher temperatures – 900 °С and 950 °С respectively. For all the systems it was shown that the alloys with eutectic compositions differ significantly in their electric and magnetic properties from hypo- and hypereutectic ones. Qualitative and quantitative metallographic analysis for Sn-3.8wt.%Ag-0.7wt.%Cu samples, heated low and above characteristic temperatures, showed the influence of melt overheating on crystallization kinetics.

Responses of soil physical and chemical properties to karst rocky desertification evolution in typical karst valley area

Science.gov (United States)

Chen, Fei; Zhou, Dequan; Bai, Xiaoyong; zeng, Cheng; Xiao, Jianyong; Qian, Qinghuan; Luo, Guangjie

2018-01-01

In order to reveal the differences of soil physical and chemical properties and their response mechanism to the evolution of KRD. The characteristics of soil physical and chemical properties of different grades of KRD were studied by field sampling method to research different types of KRD in the typical karst valley of southern China. Instead of using space of time, to explore the response and the mechanisms of the soil physical and chemical properties at the different evolution process. The results showed that: (1) There were significant differences in organic matter, pH, total nitrogen, total phosphorus, total potassium, sediment concentration, clay content and AWHC in different levels of KRD environment. However, these indicators are not with increasing desertification degree has been degraded, but improved after a first degradation trends; (2) The correlation analysis showed that soil organic matter, acid, alkali, total nitrogen, total phosphorus, total potassium and clay contents were significantly correlated with other physical and chemical factors. They are the key factors of soil physical and chemical properties, play a key role in improving soil physical and chemical properties and promoting nutrient cycling; (3) The principal component analysis showed that the cumulative contribution rate of organic matter, pH, total nitrogen, total phosphorus, total potassium and sediment concentration was 80.26%, which was the key index to evaluate rocky desertification degree based on soil physical and chemical properties. The results have important theoretical and practical significance for the protection and restoration of rocky desertification ecosystem in southwest China.

Mechanical properties and dependence with temperature of tetragonal polycrystalline zirconia materials

International Nuclear Information System (INIS)

Orange, G.

1986-01-01

Polycrystalline zirconia materials with a high content of metastable tetragonal phase have been obtained by pressureless sintering from experimental powders. Mechanical properties have been determined at room temperature and compared with similar materials. The fracture strength (σ /SUB f/ ) and fracture toughness (K /SUB 1c/ ) temperature dependence has been studied, in air environment up to 1000 0 C. Microstructure was studied by SEM examinations of fracture faces and TEM observations. Fracture toughness (of about 10 MPa √m at room temperature) decreases from 200 0 C to 800 0 C. The critical temperature (T /SUB c/ ) is estimated at 600 0 C. We observe an important decreases of fracture strength at 200 0 C. These mechanical properties are discussed on the basis of the stability of the tetragonal phase depending on additive content, grain size and temperature

Soil chemical and physical properties that differentiate urban land-use and cover types

Science.gov (United States)

R.V. Pouyat; I.D. Yesilonis; J. Russell-Anelli; N.K. Neerchal

2007-01-01

We investigated the effects of land use and cover and surface geology on soil properties in Baltimore, MD, with the objectives to: (i) measure the physical and chemical properties of surface soils (0?10 cm) by land use and cover; and (ii) ascertain whether land use and cover explain differences in these properties relative to surface geology. Mean and median values of...

Physical properties of dense, low-temperature plasmas

International Nuclear Information System (INIS)

Redmer, R.

1997-01-01

Plasmas occur in a wide range of the density-temperature plane. The physical quantities can be expressed by Green's functions which are evaluated by means of standard quantum statistical methods. The influences of many-particle effects such as dynamic screening and self-energy, structure factor and local-field corrections, formation and decay of bound states, degeneracy and Pauli exclusion principle are studied. As a basic concept for partially ionized plasmas, a cluster decomposition is performed for the self-energy as well as for the polarization function. The general model of a partially ionized plasma interpolates between low-density, nonmetallic systems such as atomic vapors and high-density, conducting systems such as metals or fully ionized plasmas. The equations of state, including the location of the critical point and the shape of the coexistence curve, are determined for expanded alkali-atom and mercury fluids. The occurrence of a metal-nonmetal transition near the critical point of the liquid-vapor phase transition leads in these materials to characteristic deviations from the behavior of nonconducting fluids such as the inert gases. Therefore, a unified approach is needed to describe the drastic changes of the electronic properties as well as the variation of the physical properties with the density. Similar results are obtained for the hypothetical plasma phase transition in hydrogen plasma. The transport coefficients (electrical and thermal conductivity, thermopower) are studied wthin linear response theory given here in the formulation of Zubarev which is valid for arbitrary degeneracy and yields the transport coefficients for the limiting cases of nondegenerate, weakly coupled plasmas (Spitzer theory) as well as degenerate, strongly coupled plasmas (Ziman theory). mercury within the MHNC scheme via effective ion-ion potentials which are derived from the polarization function within an extended RPA. The optical properties of dense plasmas, the shift

Creating Spin-One Fermions in the Presence of Artificial Spin-Orbit Fields: Emergent Spinor Physics and Spectroscopic Properties

Science.gov (United States)

Kurkcuoglu, Doga Murat; de Melo, C. A. R. Sá

2018-05-01

We propose the creation and investigation of a system of spin-one fermions in the presence of artificial spin-orbit coupling, via the interaction of three hyperfine states of fermionic atoms to Raman laser fields. We explore the emergence of spinor physics in the Hamiltonian described by the interaction between light and atoms, and analyze spectroscopic properties such as dispersion relation, Fermi surfaces, spectral functions, spin-dependent momentum distributions and density of states. Connections to spin-one bosons and SU(3) systems is made, as well relations to the Lifshitz transition and Pomeranchuk instability are presented.

Study of physical properties of UO2 quality improvement result

International Nuclear Information System (INIS)

Rachmat-Pratomo; Hidayati; Didiek Herhady, R; Busron-Masduki

1996-01-01

Activation of uranium dioxide (UO 2 ) by reoxidation to U 3 O 8 and reduction to uranium dioxide (UO 2 ) by temperature reduction variation of 850 o C and 900 o C for 3 hours has been studied. The physical properties before and after treatment are compared. It proved that the oxidation-reduction cycle increased the physical properties. It can be concluded that the reoxidation of UO 2 to U 3 O 8 on fourth cycle and reduction at 900 o C for 3 hours result in a density of 1.32 gram/ml a tap density of 1.60 gram/ml, true density of 9.08 gram/ml and O/U ratio : 2.04. Reduction at 850 o C, for 3 hours result in the bulk density of 1.30 gram/ml, tap density of 1.58 gram/ml, true density of 9.04 gram/ml and O/U ratio 2.09

Investigation of physical imaging properties in various digital radiography systems

Energy Technology Data Exchange (ETDEWEB)

Jeong, Hoi Woun [Dept. of Radiological Science, Baekseok Culture University, Cheonan (Korea, Republic of); Min, Jung Hwan [Dept. of Radiological technology, Shingu University, Seongnam (Korea, Republic of); Yoon, Yong Su [Dept. of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Kyushu (Japan); Kim, Jung Min [Dept. of Health and Environmental Science, College of Health Science, Korea University, Seoul (Korea, Republic of)

2017-09-15

We aimed to evaluate the physical imaging properties in various digital radiography systems with charged coupled device (CCD), computed radiography (CR), and indirect flat panel detector (FPD). The imaging properties measured in this study were modulation transfer function (MTF) wiener spectrum (WS), and detective quantum efficiency (DQE) to compare the performance of each digital radiography system. The system response of CCD were in a linear relationship with exposure and that of CR and FPD were proportional to the logarithm of exposure. The MTF of both CR and FPD indicated a similar tendency but in case of CCD, it showed lower MTF than that of CR and FPD. FPD showed the lowest WS and also indicated the highest DQE among three systems. According to the results, digital radiography system with different type of image receptor had its own image characteristics. Therefore, it is important to know the physical imaging characteristics of the digital radiography system accurately to obtain proper image quality.

Physical properties of inorganic PMW-PNN-PZT ceramics

Science.gov (United States)

Sin, Sang-Hoon; Yoo, Ju-hyun; Kim, Yong-Jin; Baek, Sam-ki; Ha, Jun-Soo; No, Chung-Han; Song, Hyun-Seon; Shin, Dong-Chan

2015-07-01

In this work, inorganic Pb(Mg1/2W1/2)0.03(Ni1/3Nb2/3)x(Zr0.5Ti0.5)0.97-xO3 (x = 0.02 ∼ 0.12) composition ceramics were fabricated by the conventional solid state reaction method. And then their micro structure and ferroelectric properties were investigated according to the amount of PNN substitution. Small amounts of Li2CO3 and CaCO3 were used in order to decrease the sintering temperature of the ceramics. The 0.10 mol PNN-substituted PMW-PNN- PZT ceramics sintered at 920°C showed the excellent physical properties of piezoelectric constant (d33), electromechanical coupling factor (kp), mechanical quality coefficient (Qm), and dielectric constant of 566 pC/N, 0.61, 73, and 2183, respectively.

Size-dependent impact of CNTs on dynamic properties of calmodulin.

Science.gov (United States)

Gao, Jian; Wang, Liming; Kang, Seung-gu; Zhao, Lina; Ji, Mingjuan; Chen, Chunying; Zhao, Yuliang; Zhou, Ruhong; Li, Jingyuan

2014-11-07

There are growing concerns about the biosafety of nanomaterials such as carbon nanotubes (CNTs) as their applications become more widespread. We report here a theoretical and experimental study of the binding of various sizes of CNTs [CNT (4,4), (5,5), (6,6) and (7,7)] to calmodulin (CaM) protein and, in particular, their impact on the Ca(2+)-dependent dynamic properties of CaM. Our simulations show that all the CNTs can plug into the hydrophobic binding pocket of Ca(2+)-bound CaM with binding affinities comparable with the native substrate M13 peptide. Even though CNT (4,4) shows a similar behavior to the M13 peptide in its dissociation from Ca(2+)-free CaM, wider CNTs still bind firmly to CaM, indicating a potential failure of Ca(2+) regulation. Such a size-dependent impact of CNTs on the dynamic properties of CaM is a result of the excessively strong hydrophobic interactions between the wider CNTs and CaM. These simulation results were confirmed by circular dichroism spectroscopy, which showed that the secondary structures of CaM become insensitive to Ca(2+) concentrations after the addition of CNTs. Our findings indicate that the cytotoxicity of nanoparticles to proteins arises not only from the inhibition of static protein structures (binding pockets), but also from impacts on their dynamic properties.

Sex differences in disinhibition and its relationship to physical abuse in a sample of stimulant-dependent patients.

Science.gov (United States)

Winhusen, Theresa; Lewis, Daniel

2013-04-01

Research suggests that impulsivity is a vulnerability factor for developing stimulant dependence, that women develop dependence more quickly than men, and that physical abuse can increase impulsivity and may have greater adverse health consequences in women. This study sought to tie these findings together by evaluating: (1) sex differences in disinhibition prior to lifetime initiation of stimulant abuse and (2) the relationship between physical abuse and disinhibition in stimulant-dependent patients. The Frontal Systems Behavior Scale (FrSBe) is a reliable and valid self-report assessment of three neurobehavioral domains associated with frontal systems functioning (Apathy, Disinhibition, and Executive Dysfunction, summed for a Total), that assesses pre-morbid functioning and has a specific cutoff for defining clinically significant abnormalities. Six sites evaluating 12-step facilitation for stimulant abusers obtained the FrSBe from 118 methamphetamine- and/or cocaine-dependent participants. Lifetime physical abuse was measured by the Addiction Severity Index (ASI). The proportion reporting clinically significant disinhibition was significantly higher in women (64.9%) than in men (45.0%, p=0.04), with no significant difference on the other FrSBe scales. Physical abuse in women, but not men, was associated with worse functioning, with physically abused, relative to non-abused, women having a significantly greater proportion with clinically significant disinhibition (pabuse and that physical abuse in women is associated with greater disinhibition. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Synthesis, microstructure, and physical properties of metallic barcode nanowires

Science.gov (United States)

Park, Bum Chul; Kim, Young Keun

2017-05-01

With rapid progress in nanotechnology, nanostructured materials have come closer to our life. Single-component nanowires are actively investigated because of their novel properties, attributed to their nanoscale dimensions and adjustable aspect ratio, but their technical limitations cannot be resolved easily. Heterostructured nanomaterials gained attention as alternatives because they can improve the existing single-component structure or add new functions to it. Among them, barcode nanowires (BNWs), comprising at least two different functional segments, can perform multiple functions for use in biomedical sensors, information encoding and security, and catalysts. BNW applications require reliable response to the external field. Hence, researchers have been attempting to improve the reliability of synthesis and regulate the properties precisely. This article highlights the recent progress and prospects for the synthesis, properties, and applications of metallic BNWs with focus on the dependence of the magnetic, optical, and mechanical properties on material, composition, shape, and microstructure.

Physical properties of the half-filled Hubbard model in infinite dimensions

International Nuclear Information System (INIS)

Georges, A.; Krauth, W.

1993-01-01

A detailed quantitative study of the physical properties of the infinite-dimensional Hubbard model at half filling is presented. The method makes use of an exact mapping onto a single-impurity model supplemented by a self-consistency condition. This coupled problem is solved numerically. Results for thermodynamic quantities (specific heat, entropy, . . .), one-particle spectral properties, and magnetic properties (response to a uniform magnetic field) are presented and discussed. The nature of the Mott-Hubbard metal-insulator transition found in this model is investigated. A numerical solution of the mean-field equations inside the antiferromagnetic phase is also reported

Physical properties of peats as related to degree of decomposition

Science.gov (United States)

D.H. Boelter

1969-01-01

Important physical characteristics, such as water retention, water yield coefficient, and hydraulic conductivity, vary greatly for representative northern Minnesota peat materials. The differences are related to the degree of decomposition, which largely determines the porosity and pore size distribution. Fiber content (> 0.1 mm) and bulk density are properties...

Strain-dependent dynamic compressive properties of magnetorheological elastomeric foams

Science.gov (United States)

Wereley, Norman M.; Perez, Colette; Choi, Young T.

2018-05-01

This paper addresses the strain-dependent dynamic compressive properties (i.e., so-called Payne effect) of magnetorheological elastomeric foams (MREFs). Isotropic MREF samples (i.e., no oriented particle chain structures), fabricated in flat square shapes (nominal size of 26.5 mm x 26.5 mm x 9.5 mm) were synthesized by randomly dispersing micron-sized iron oxide particles (Fe3O4) into a liquid silicone foam in the absence of magnetic field. Five different Fe3O4 particle concentrations of 0, 2.5, 5.0, 7.5, and 10 percent by volume fraction (hereinafter denoted as vol%) were used to investigate the effect of particle concentration on the dynamic compressive properties of the MREFs. The MREFs were sandwiched between two multi-pole flexible plate magnets in order to activate the magnetorheological (MR) strengthening effect. Under two different pre-compression conditions (i.e., 35% and 50%), the dynamic compressive stresses of the MREFs with respect to dynamic strain amplitudes (i.e., 1%-10%) were measured by using a servo-hydraulic testing machine. The complex modulus (i.e., storage modulus and loss modulus) and loss factors of the MREFs with respect to dynamic strain amplitudes were presented as performance indices to evaluate their strain-dependent dynamic compressive behavior.

Strain-dependent dynamic compressive properties of magnetorheological elastomeric foams

Directory of Open Access Journals (Sweden)

Norman M. Wereley

2018-05-01

Full Text Available This paper addresses the strain-dependent dynamic compressive properties (i.e., so-called Payne effect of magnetorheological elastomeric foams (MREFs. Isotropic MREF samples (i.e., no oriented particle chain structures, fabricated in flat square shapes (nominal size of 26.5 mm x 26.5 mm x 9.5 mm were synthesized by randomly dispersing micron-sized iron oxide particles (Fe3O4 into a liquid silicone foam in the absence of magnetic field. Five different Fe3O4 particle concentrations of 0, 2.5, 5.0, 7.5, and 10 percent by volume fraction (hereinafter denoted as vol% were used to investigate the effect of particle concentration on the dynamic compressive properties of the MREFs. The MREFs were sandwiched between two multi-pole flexible plate magnets in order to activate the magnetorheological (MR strengthening effect. Under two different pre-compression conditions (i.e., 35% and 50%, the dynamic compressive stresses of the MREFs with respect to dynamic strain amplitudes (i.e., 1%-10% were measured by using a servo-hydraulic testing machine. The complex modulus (i.e., storage modulus and loss modulus and loss factors of the MREFs with respect to dynamic strain amplitudes were presented as performance indices to evaluate their strain-dependent dynamic compressive behavior.

Physical properties of heat-treated rattan waste binderless particleboard

Science.gov (United States)

Tajuddin, Maisarah; Ahmad, Zuraida; Halim, Zahurin; Maleque, Md Abd; Ismail, Hanafi; Sarifuddin, Norshahida

2017-07-01

The objective of this study is to investigate the effects of heat treatment on the properties of binderless particleboard (BPB) fabricated via hot-pressing process with pressing temperature, pressing time and pressing pressure of 180°C, 5 minutes and 1 MPa, respectively. The fabricated BPB with density in the range of 0.8-0.95g cm-3 was heated in a temperature-controlled laboratory chamber at 80°C, 120°C and 160°C for period of 2 and 8 hours before underwent physical observation, mass loss measurement and thickness swelling test. The samples had remarkable color changes, mainly with samples of treatment temperature of 160˚C, where the color differences were 9.5 and 20.3. This changed the fabricated BPB samples from yellowish brown to dark brown color when treatment conditions increased. Darker color indicates greater mass loss due to severity of chemical component in the powder. Dimensional stability of fabricated BPB was improved with higher treatment temperature as more cellulose cross-linked and hemicellulose degraded that removed the hygroscopicity behavior of powder. These results revealed that heat treatment helped in improving the BPB physical properties, particularly in dimensional stability of boards.

PHYSICAL PROPERTIES OF LARGE AND SMALL GRANULES IN SOLAR QUIET REGIONS

Energy Technology Data Exchange (ETDEWEB)

Yu Daren; Xie Zongxia; Hu Qinghua [Harbin Institute of Technology, Harbin 150001 (China); Yang Shuhong; Zhang Jun; Wang Jingxiu, E-mail: caddiexie@hotmail.com, E-mail: zjun@ourstar.bao.ac.cn [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

2011-12-10

The normal mode observations of seven quiet regions obtained by the Hinode spacecraft are analyzed to study the physical properties of granules. An artificial intelligence technique is introduced to automatically find the spatial distribution of granules in feature spaces. In this work, we investigate the dependence of granular continuum intensity, mean Doppler velocity, and magnetic fields on granular diameter. We recognized 71,538 granules by an automatic segmentation technique and then extracted five properties: diameter, continuum intensity, Doppler velocity, and longitudinal and transverse magnetic flux density to describe the granules. To automatically explore the intrinsic structures of the granules in the five-dimensional parameter space, the X-means clustering algorithm and one-rule classifier are introduced to define the rules for classifying the granules. It is found that diameter is a dominating parameter in classifying the granules and two families of granules are derived: small granules with diameters smaller than 1.''44, and large granules with diameters larger than 1.''44. Based on statistical analysis of the detected granules, the following results are derived: (1) the averages of diameter, continuum intensity, and Doppler velocity in the upward direction of large granules are larger than those of small granules; (2) the averages of absolute longitudinal, transverse, and unsigned flux density of large granules are smaller than those of small granules; (3) for small granules, the average of continuum intensity increases with their diameters, while the averages of Doppler velocity, transverse, absolute longitudinal, and unsigned magnetic flux density decrease with their diameters. However, the mean properties of large granules are stable; (4) the intensity distributions of all granules and small granules do not satisfy Gaussian distribution, while that of large granules almost agrees with normal distribution with a peak at 1.04 I

Influence of alkaline treatment and fiber loading on the physical and mechanical properties of kenaf/polypropylene composites for variety of applications☆

Institute of Scientific and Technical Information of China (English)

Majid Niaz Akhtar; Abu Bakar Sulong; M.K. Fadzly Radzi; N.F. Ismail; M.R. Raza; Norhamidi Muhamad; Muhammad Azhar Khan

2017-01-01

Due to current trend and increasing interest towards natural based fiber products, Kenaf (Hibiscus cannabinus) fibers have been used for the developments of many products. Therefore, Kenaf fiber-reinforced composites have been widely used in engineering and industrial applications. The present work deals with the fabricating and characterization of untreated and treated kenaf/polypropylene (PP)-reinforced composites. Composites of PP reinforced with treated and untreated kenaf fibers were fabricated using the injection molding technique. Different fiber loadings of 10, 20, 30, 40, 50 wt%treated and untreated kenaf composites were also prepared. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and thermo gravimetric analysis (TGA) were performed on the treated, untreated kenaf fibers and kenaf/PP composites. Moreover, the alkaline-treated kenaf composites exhibit better physical, morphological, and mechanical properties because of the compatibility of kenaf with PP. However, variations in tensile and flexural properties depend on treatment and kenaf fiber contents. The percentage increase in the mechanical properties of the treated kenaf/PP composites relative to that of PP was also measured. In addition, 40 wt%kenaf fiber loading resulted in higher mechanical properties. By contrast, kenaf/PP composite with 50%fiber loading was not successfully prepared because of improper mixing and the burning of kenaf fibers in the PP matrix. To conclude, 40%kenaf/PP composites with superior physical and mechanical properties may be used in variety of applications such as automotive, sports, construction, animal bedding, and mass production industries.

Physical properties, structure and fracturing of the Chelyabinsk LL5 meteorite body

Czech Academy of Sciences Publication Activity Database

Grokhovsky, V. I.; Kohout, Tomáš; Gritsevich, M.; Koneva, E. V.

2014-01-01

Roč. 49, Special issue 1 (2014), pdf 5364-pdf 5364 ISSN 1086-9379. [Annual Meeting of the Meteoritical Society /77./. 08.09.2014-13.09.2014, Casablanca] Institutional support: RVO:67985831 Keywords : Chelyabinsk * LL chondrite * physical properties * structure * mechanical properties * stress Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics http://www.hou.usra.edu/meetings/metsoc2014/pdf/5364.pdf

Depth-Dependent Temporal Response Properties in Core Auditory Cortex

OpenAIRE

Christianson, G. Björn; Sahani, Maneesh; Linden, Jennifer F.

2011-01-01

The computational role of cortical layers within auditory cortex has proven difficult to establish. One hypothesis is that interlaminar cortical processing might be dedicated to analyzing temporal properties of sounds; if so, then there should be systematic depth-dependent changes in cortical sensitivity to the temporal context in which a stimulus occurs. We recorded neural responses simultaneously across cortical depth in primary auditory cortex and anterior auditory field of CBA/Ca mice, an...

Evaluation of the mechanical and physical properties of a posterior ...

African Journals Online (AJOL)

To evaluate the mechanical and physical properties of a micro-hybrid resin composite used in adult posterior restorations A micro-hybrid, light curing resin composite Unolux BCS Composite Restorative, (UnoDent, England) was used to restore 74 carious classes I and II cavities on posterior teeth of 62 adult patients.

Numerical properties of staggered quarks with a taste-dependent mass term

CERN Document Server

de Forcrand, Philippe; Panero, Marco

2012-01-01

The numerical properties of staggered Dirac operators with a taste-dependent mass term proposed by Adams [1,2] and by Hoelbling [3] are compared with those of ordinary staggered and Wilson Dirac operators. In the free limit and on (quenched) interacting configurations, we consider their topological properties, their spectrum, and the resulting pion mass. Although we also consider the spectral structure, topological properties, locality, and computational cost of an overlap operator with a staggered kernel, we call attention to the possibility of using the Adams and Hoelbling operators without the overlap construction. In particular, the Hoelbling operator could be used to simulate two degenerate flavors without additive mass renormalization, and thus without fine-tuning in the chiral limit.

Effect of Structure on Physical Properties of Polymers.

Science.gov (United States)

1979-12-31

PORT NUMBE . J ! 2. GOVT ACCESSION NO. 3. RECIPIENT’S CATALOG NUMBER OSRT R’.-8 00 7 5 0 4_7_5_ Effecc of Structure on Physical Properties of -Final...Compatibility of Fluorosubstituted Styrene Polymers with PPO and PS. R. Vukovic , F.E. Karasz, W.J. MacKnight, (in press). (6) Compatibility of Ortho- and Para...fluorostyrene Copolymers with PPO and PS. R. Vukovic , F.E. Karasz, W.J. MacKnight, (in press). (7) Partial Miscibility in the System Poly (para

Physical and Sensory Properties of Ice Cream Containing Fermented Pepper Powder.

Science.gov (United States)

Yeon, Su-Jung; Kim, Ji-Han; Hong, Go-Eun; Park, Woojoon; Kim, Soo-Ki; Seo, Han-Geuk; Lee, Chi-Ho

2017-01-01

This study was conducted to investigate the physical and sensory properties of ice cream containing fermented pepper powder. Three ice cream formulas were manufactured: 1, control; 2, supplemented with 0.1% fermented pepper powder; and 3, supplemented with 0.2% fermented pepper powder. Formulas 2 and 3 had significantly higher viscosity and lower overrun than formula 1 ( p ice creams supplemented with fermented pepper powder were harder and maintained their forms longer than the controls. 0.2% fermented pepper powder added ice cream had no pungency as much as that of control and overall sensory attribute was not significantly different from control. Therefore, ice cream containing fermented pepper powder maintained physical and sensory properties similar to the controls, and maintenance was better. It means fermented pepper powder ice cream can be utilized as the material of functional food (dessert).

Mutual associations among microstructural, physical and mechanical properties of human cancellous bone

DEFF Research Database (Denmark)

Ding, Ming; Odgaard, A; Danielsen, CC

2002-01-01

structure and mechanical properties. In this study, 160 cancellous bone specimens were produced from 40 normal human tibiae aged from 16 to 85 years at post-mortem. The specimens underwent micro-CT and the microstructural properties were calculated using unbiased three-dimensional methods. The specimens...... were tested to determine the mechanical properties and the physical/compositional properties were evaluated. The type of structure together with anisotropy correlated well with Young's modulus of human tibial cancellous bone. The plate-like structure reflected high mechanical stress and the rod......-like structure low mechanical stress. There was a strong correlation between the type of trabecular structure and the bone-volume fraction. The most effective microstructural properties for predicting the mechanical properties of cancellous bone seem to differ with age....

Role of differential physical properties in emergent behavior of 3D cell co-cultures

Science.gov (United States)

Kolbman, Dan; Das, Moumita

2015-03-01

The biophysics of binary cell populations is of great interest in many biological processes, whether the formation of embryos or the initiation of tumors. During these processes, cells are surrounded by other cell types with different physical properties, often with important consequences. For example, recent experiments on a co-culture of breast cancer cells and healthy breast epithelial cells suggest that the mechanical mismatch between the two cell types may contribute to enhanced migration of the cancer cells. Here we explore how the differential physical properties of different cell types may influence cell-cell interaction, aggregation, and migration. To this end, we study a proof of concept model- a three-dimensional binary system of interacting, active, and deformable particles with different physical properties such as elastic stiffness, contractility, and particle-particle adhesion, using Langevin Dynamics simulations. Our results may provide insights into emergent behavior such as segregation and differential migration in cell co-cultures in three dimensions.

PHYSICAL PROPERTIES OF KAOLIN/SAND SLURRY USED DURING SUBMERSIBLE MIXER PUMP TESTS AT TNX

International Nuclear Information System (INIS)

HANSEN, ERICH

2005-01-01

The purpose of this task is to characterize the physical properties of the kaolin/sand slurries used during the testing of a new submersible mixer pump (SMP) which had undergone performance testing at the TNX Waste Tank mockup facility from July 2004 through May 2005. During this time period, four identical SMPs were subjected to various water tests and four different tests using different batches of kaolin/sand slurries. The physical properties of the kaolin/sand slurries were measured for three of the four tests. In these tests, three different sample locations were used to pull samples, the SMP cooling water exit (CWE), the SMP fluid flow field (FFF), and SMP effective cleaning radius (ECR). The physical properties measured, though not for each sample, included rheology, weight percent total solids (wt% TS), density, kaolin/sand slurry particle size distribution (PSD), weight percent and particles size distribution of material greater than 45 microns

Role of Ge incorporation in the physical and dielectric properties of ...

Indian Academy of Sciences (India)

It is inferred that on adding Ge, the physical properties ..... over a considerable distance, and the contribution to dielectric response can therefore be ... 1 and 103 Hz. The sum of these four types of polarization represents the total polarization.

Physical properties of a sediment core from the Central Indian Basin

Digital Repository Service at National Institute of Oceanography (India)

Khadge, N.H.

A box core of 7.5 m was collected from the Central Indian Basin for the purpose of geotechnical studies and depthwise variation of physical properties and clay mineralogy. Water content, Atterberg limits, specific gravity are measured at regular...

Temperature-dependent dielectric properties in ITO/AF/Al device

International Nuclear Information System (INIS)

Choi, Hyun-Min; Kim, Won-Jong; Lee, Jong-Yong; Hong, Jin-Woong; Kim, Tae-Wan

2010-01-01

Temperature-dependent dielectric properties were studied in a device with a structure of ITO/amorphous fluoropolymer (AF)/Al. The AF was thermally deposited at a deposition rate of 0.1 A/s to a thickness of 20 nm under a pressure of 5 x 10 -6 Torr. From the dielectric properties of the device, an equivalent circuit for and the equivalent complex impedance Z eq of the device were obtained. The interfacial resistance was found to be approximately 38 Ω. As the temperature was increased, the radius of the Cole-Cole plot and β also increased for a constant applied voltage. However, as the applied voltage was increased, those values decreased at a constant temperature. These behaviors are thought to be due to an orientational polarization effect of the molecules inside the AF layer.

Physical properties of elongated magnetic particles: magnetization and friction coefficient anisotropies.

Science.gov (United States)

Vereda, Fernando; de Vicente, Juan; Hidalgo-Alvarez, Roque

2009-06-02

Anisotropy counts: A brief review of the main physical properties of elongated magnetic particles (EMPs) is presented. The most important characteristic of an EMP is the additional contribution of shape anisotropy to the total anisotropy energy of the particle, when compared to spherical magnetic particles. The electron micrograph shows Ni-ferrite microrods fabricated by the authors.We present an overview of the main physical properties of elongated magnetic particles (EMPs), including some of their more relevant properties in suspension. When compared to a spherical magnetic particle, the most important characteristic of an EMP is an additional contribution of shape anisotropy to the total anisotropy energy of the particle. Increasing aspect ratios also lead to an increase in both the critical single-domain size of a magnetic particle and its resistance to thermally activated spontaneous reversal of the magnetization. For single-domain EMPs, magnetization reversal occurs primarily by one of two modes, coherent rotation or curling, the latter being facilitated by larger aspect ratios. When EMPs are used to prepare colloidal suspensions, other physical properties come into play, such as their anisotropic friction coefficient and the consequent enhanced torque they experience in a shear flow, their tendency to align in the direction of an external field, to form less dense sediments and to entangle into more intricate aggregates. From a more practical point of view, EMPs are discussed in connection with two interesting types of magnetic colloids: magnetorheological fluids and suspensions for magnetic hyperthermia. Advances reported in the literature regarding the use of EMPs in these two systems are included. In the final section, we present a summary of the most relevant methods documented in the literature for the fabrication of EMPs, together with a list of the most common ferromagnetic materials that have been synthesized in the form of EMPs.

Physical properties of root cementum: Part I. A new method for 3-dimensional evaluation.

Science.gov (United States)

Malek, S; Darendeliler, M A; Swain, M V

2001-08-01

Cementum is a nonuniform connective tissue that covers the roots of human teeth. Investigation of the physical properties of cementum may help in understanding or evaluating any possible connection to root resorption. A variety of engineering tests are available to investigate these properties. However, the thickness of the cementum layer varies, and this limits the applicability of these techniques in determining the physical properties of cementum. Hardness testing with Knoop and Vickers indentations overcame some of these limitations, but they prohibited the retrieval and retesting of the sample and therefore the testing was restricted to one area or section of the tooth. Another limiting factor with the existing techniques was the risk of artifacts related to the embedding material such as acrylic. A new method to investigate the physical properties of human premolar cementum was developed to obtain a 3-dimensional map of these properties with the Ultra Micro Indentation System (UMIS-2000; Commonwealth Scientific and Industrial Research Organization, Campbell, Australia). UMIS-2000 is a nano-indentation instrument for investigation of the properties of the near-surface region of materials. Premolars were harvested from orthodontic patients requiring extractions and then mounted on a newly designed surveyor that allowed sample retrieval and 3-dimensional rotation. This novel method enabled the quantitative testing of root surface cementum, on all 4 root surfaces, extending from the apex to the cementoenamel junction at 60 different sites.

Moisture Dependence of physical Properties and Specific Heat Capacity of Neem (Azadirachta Indica A. Juss Kernels

Directory of Open Access Journals (Sweden)

A. Dauda

2017-02-01

Full Text Available This study investigated the effect of moisture content on the physical properties and specific heat capacity of Neem (Azadirachta Indica A. Juss nut kernels. The major, intermediate and minor axial dimensions of the kernels increased from 1.04 to 1.23cm, 0.42 to 0.6cm, and 0.32 to 0.45cm respectively, as the moisture content increased from 5.2 to 44.9 % (db. The arithmetic and geometric mean diameters determined at the same moisture level were significantly different from each other, with the arithmetic mean diameter being higher. In the above moisture range, one thousand kernel weight, true density, porosity, sphericity, roundness and surface area all increased linearly from 0.0987 to 0.1755kg, 632 to 733kgm-3, 6.42 to 32.14%, 41.3 to 47.5%, 22 to 36% and 13 to 24cm2 respectively, while bulk density decreased from 591.4 to 497.4kgm-3 with increase in moisture content. Angle of repose increased from 21.22 to 29.8o with increase in moisture content. The Static coefficient of friction on ply wood with grains parallel to the direction of movement ranged from 0.41 to 0.61, it ranged from 0.19 to 0.24 on on fiber glass, 0.28 to .038 on hessian bag material and 0.25 to 0.33 on galvanized steel sheet. The specific heat of the seed varied from 2738.1- 4345.4J/kg/oC in the above moisture range.

Postharvest Chemical, Sensorial and Physical-Mechanical Properties of Wild Apricot (Prunus armeniaca L.

Directory of Open Access Journals (Sweden)

Evica MRATINIĆ

2011-11-01

Full Text Available Some chemical, sensorial and physical-mechanical properties of 19 apricot genotypes and Hungarian Best (control such as moisture content, soluble solids content, titratable acidity ratio and their ratio, fruit and stone mass, flesh/stone ratio, fruit dimensions (length, width, thickness, arithmetic and geometric mean diameter, sphericity, surface area and aspect ratio were determined. Their application is also discussed. The highest moisture content and stone mass observed in X-1/1/04 and X-1/2/04, soluble solids content in ZO-1/03, titratable acidity in ZL-2/03, SS/TA ratio in ZL-1/03, and fruit mass and flesh/stone ratio in DL-1/1/04 genotype. The most number of genotypes have orange and deep orange skin and flesh colour, respectively, whereas sweet kernel taste was predominant in most genotypes. Regarding physical-mechanical properties, the superior fruit dimensions (length, width, thickness, arithmetic and geometric mean diameter and surface area observed in DL-1/1/04 genotype, whereas the highest sphericity and surface area observed in X-1/1/04 and X-1/2/04 genotypes. Also, the series of genotypes evaluated have better chemical, sensorial and physical-mechanical properties than Hungarian Best (control. Finally, information about these properties is very important for understanding the behaviour of the product during the postharvest operations.

Physical Properties and Specific Heat Capacity of Tamarind (Tamarindus indica Seed

Directory of Open Access Journals (Sweden)

A. Dauda

2017-04-01

Full Text Available This study investigated the effect of moisture content on physical properties and specific heat capacity of Tamarindus indica seed. Physical properties investigated were axial dimensions, one thousand seed weight, bulk and true densities, porosity, roundness and sphericity, surface area, angle of repose and static coefficient of friction. The thermal property determined was the specific heat. These properties of Tamarindus indica seed were investigated within the moisture content range of 7.55 - 10.47% (d.b. The length, width and thickness increased from 9.979 to 10.634mm, 8.909 to 10.089mm and 5.039 to 5.658mm, respectively in the above moisture range. One thousand seed weight, surface area, seed volume, true density and porosity, increased from 388.4 to 394.8g, 86.916 to 87.58cm2, 0.353 to 0.366cm3, 1217.5 to 1287.00kg/m3 and 28.22 to 33.87%, respectively, as moisture content increased in the above range, while bulk density decreased from 873.9 to 851.4kg/m3. Roundness and sphericity, and angle of repose also increased from 41 to 42.4% and 73.7 to 76.3% and 36.1 to 38.93o, respectively. Specific heat capacity values increased linearly from 589.00J/kgK to 638.61 J/kgK in the above moisture range.

Physical and arsenic adsorption properties of maghemite and magnetite sub-microparticles

Science.gov (United States)

Mejia-Santillan, M. E.; Pariona, N.; Bravo-C., J.; Herrera-Trejo, M.; Montejo-Alvaro, F.; Zarate, A.; Perry, D. L.; Mtz-Enriquez, A. I.

2018-04-01

The topotactic transformation from magnetite to maghemite sub-microparticles was demonstrated by a variety of techniques that include X-ray diffraction, Raman spectroscopy, electron microscopy, Mössbauer spectroscopy, magnetic measurements, and vis-NIR diffuse reflectance. The physical, chemical, and morphological properties of the particles were correlated with their adsorptive properties in water with respect to arsenic (V). The adsorptive properties of the iron oxide are increased by changing the crystal phases involved, specifically, the transformation of magnetite to maghemite. Maghemite sub-microparticles are capable of efficiently decreasing the arsenic content in water from 100 ppb to below the World Health Organization (WHO) guideline of 10 ppb.

Why Density Dependent Propulsion?

Science.gov (United States)

Robertson, Glen A.

2011-01-01

In 2004 Khoury and Weltman produced a density dependent cosmology theory they call the Chameleon, as at its nature, it is hidden within known physics. The Chameleon theory has implications to dark matter/energy with universe acceleration properties, which implies a new force mechanism with ties to the far and local density environment. In this paper, the Chameleon Density Model is discussed in terms of propulsion toward new propellant-less engineering methods.

Selected Physical Properties of Andisols under Different Land Use Condition in Gunung Kerinci Subdistrict, Jambi

Directory of Open Access Journals (Sweden)

Endriani

2010-05-01

Full Text Available Objective of the research was to study the effect of different land use at some land slopecondition on some physical properties of Andisols in Gunung Kerinci Subdistrict, Jambi.. The research was conductusing field survey and purposive random sampling methods to collect soil. The land use which was using in this studywere: forest, cultivation, cinnamon, and coffee plantation, while land slope level weres: 3-8%, 8-15%, 15-25 %, and> 25%. The results showed that among land use types, the rank of soil physical properties, such as: soil organicmatter, bulk density, porosity, percentage of agregation, stability of agregate, pore distribution and permeability werein order of : forest > cultivation > cinnamon > coffee. Land conversion from forest to agricultural land causeddecreasing in the soil physical properties. The higher level of land slope caused the decreasing of soil physicalproperties at all type of land use.

The Effect of Moisture Content on Physical Properties of Berberis

Directory of Open Access Journals (Sweden)

E Velayati

2011-03-01

Full Text Available In order to enhance the mechanization level of harvest and post-harvest operations of Berberis fruit, as one of the major and local crops of south Khorasan province, some of its physical properties were investigated. Different dimensions, geometrical mean diameter, sphericity, surface area, mass of thousand fruit, true density, bulk density, porosity, static coefficient of friction and the repose angles were determined. The properties and the effect of moisture content on them were studied by the completely randomized designs statistical method. Analysis of data indicated that the change of moisture content caused significant difference (P

THE PHYSICAL PROPERTIES OF HEARTWOOD AND SAPWOOD OF EUCALYPTUS GRANDIS

Directory of Open Access Journals (Sweden)

Bekir Cihad BAL

2012-12-01

Full Text Available In this study, some of the physical propertiesof heartwood and sapwood of Eucalyptus grandisgrown in Karabucak, Turkey were determined. Thephysical properties determined were air-drieddensity, oven-dried density, basic density, shrinkage,swelling, fiber saturation point, and maximummoisture content. According to the test results, thephysical properties of the heartwood samplesdiffered from those of the sapwood samples due tothe presence of high proportion of juvenile wood inthe heartwood. It can be said that the shrinkage andswelling percentages were better for heartwood thansapwood. Air-dried density, oven-dried density, andbasic density of sapwood were higher than those ofheartwood.

Risk factor characteristics in carers who physically abuse or neglect their elderly dependants.

Science.gov (United States)

Reay, A M; Browne, K D

2001-02-01

This study investigates the prevalence of, and differences in, risk factor characteristics in a sample of two select populations of carers, one of which physically abused their elderly dependants and one of which neglected them. Nineteen carers (nine who had physically abused and 10 who had neglected their elderly relatives), who were referred to clinical psychology by either their general practitioner or their psychiatrist, were invited to take part in this study. A detailed history of risk factors was obtained, including history of alcohol dependency, type and history of mental ill health, history of maltreatment earlier in life, who they were caring for, how long they had been a carer and whether they felt isolated as a carer. Subjects were then given five assessments to determine whether there were any differences between the two groups. These were the Conflict Tactic Scale, Strain Scale, Beck Depression Inventory, Beck Anxiety Inventory and Cost of Care Index. An examination of the risk factors suggests that heavy alcohol consumption and past childhood abuse by fathers were likely to lead to physical abuse. Significantly higher conflict and depression scores were also present in the physical abuse group, while the neglect group had significantly higher anxiety scores. It is suggested that these findings should be incorporated into an assessment of future risk of abuse or neglect by the carer.

Temperature dependence of elastic properties in austenite and martensite of Ni-Mn-Ga epitaxial films

Czech Academy of Sciences Publication Activity Database

Heczko, Oleg; Seiner, Hanuš; Stoklasová, Pavla; Sedlák, Petr; Sermeus, J.; Glorieux, C.; Backen, A.; Fähler, S.; Landa, Michal

2018-01-01

Roč. 145, Feb (2018), s. 298-305 ISSN 1359-6454 R&D Projects: GA ČR GA17-00062S Institutional support: RVO:68378271 ; RVO:61388998 Keywords : magnetic shape memory alloys * elastic properties * surface acoustic waves * Ni 2 MnGa * NiMnGa Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.); Acoustics (UT-L) Impact factor: 5.301, year: 2016

Probabilistic-Stochastic Model of Distribution of Physical and Mechanical Properties of Soft Mineral Rocks

Directory of Open Access Journals (Sweden)

O.O. Sdvizhkova

2017-12-01

Full Text Available The physical and mechanical characteristics of soils and soft rocks obtained as a result of laboratory tests are important initial parameters for assessing the stability of natural and artificial slopes. Such properties of rocks as adhesion and the angle of internal friction are due to the influence of a number of natural and technogenic factors. At the same time, from the set of factors influencing the stability of the slope, the most significant ones are singled out, which to a greater extent determine the properties of the rocks. The more factors are taken into account in the geotechnical model, the more closely the properties of the rocks are studied, which increases the accuracy of the scientific forecast of the landslide danger of the slope. On the other hand, an increase in the number of factors involved in the model complicates it and causes a decrease in the reliability of geotechnical calculations. The aim of the work is to construct a statistical distribution of the studied physical and mechanical properties of soft rocks and to substantiate a probabilistic statistical model. Based on the results of laboratory tests of rocks, the statistical distributions of the quantitative traits studied, the angle of internal friction φ and the cohesion, were constructed. It was established that the statistical distribution of physical mechanical properties of rocks is close to a uniform law.

Rheological and physical properties of spray-dried mucilage obtained from Hylocereus undatus cladodes.

Science.gov (United States)

García-Cruz, E E; Rodríguez-Ramírez, J; Méndez Lagunas, L L; Medina-Torres, L

2013-01-02

This study examines the rheological behavior of reconstituted spray-dried mucilage isolated from the cladodes of pitahaya (Hylocereus undatus), the effects of concentration and its relationship with physical properties were analyzed in reconstituted solutions. Drying process optimization was carried out through the surface response method, utilizing a factorial 2(3) design with three central points, in order to evaluate yield and rheological properties. The reconstituted mucilage exhibited non-Newtonian shear-thinning behavior, which adequately fit the Cross model (R(2)>0.95). This dynamic response suggests a random coil configuration. The steady-shear viscosity and dynamic response are suitably correlated through the Cox-Merz rule, confirming the mucilage's stability of flow. Analysis of the physical properties of the mucilage (Tg, DTP, and particle morphology) explains the shear-thinning behavior. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of Uncertainties in Physical Property Estimates on Process Design - Sensitivity Analysis

DEFF Research Database (Denmark)

Hukkerikar, Amol; Jones, Mark Nicholas; Sin, Gürkan

for performing sensitivity of process design subject to uncertainties in the property estimates. To this end, first uncertainty analysis of the property models of pure components and their mixtures was performed in order to obtain the uncertainties in the estimated property values. As a next step, sensitivity......Chemical process design calculations require accurate and reliable physical and thermodynamic property data and property models of pure components and their mixtures in order to obtain reliable design parameters which help to achieve desired specifications. The uncertainties in the property values...... can arise from the experiments itself or from the property models employed. It is important to consider the effect of these uncertainties on the process design in order to assess the quality and reliability of the final design. The main objective of this work is to develop a systematic methodology...

Ground-based forest harvesting effects on soil physical properties and Douglas-fir growth.

Science.gov (United States)

Adrian Ares; Thomas A. Terry; Richard E. Miller; Harry W. Anderson; Barry L. Flaming

2005-01-01

Soil properties and forest productivity can be affected by heavy equipment used for harvest and site preparation but these impacts vary greatly with site conditions and operational practices. We assessed the effects of ground-based logging on soil physical properties and subsequent Douglas-fir [Pseudotsuga menziesii (Mirb) Franco] growth on a highly...

Physical, mechanical, and biodegradable properties of meranti wood polymer composites

International Nuclear Information System (INIS)

Enamul Hoque, M.; Aminudin, M.A.M.; Jawaid, M.; Islam, M.S.; Saba, N.; Paridah, M.T.

2014-01-01

Highlights: • In-situ polymerization and solution casting method used to manufacture WPC. • In-situ WPC exhibited better properties compared to pure wood, 5% WPC and 20% WPC. • Lowest water absorption and least biodegradability shown by In-situ wood. - Abstract: In-situ polymerization and solution casting techniques are two effective methods to manufacture wood polymer composites (WPCs). In this study, wood polymer composites (WPCs) were manufactured from meranti sapwood by solution casting and in-situ polymerization process using methyl methacrylate (MMA) and epoxy matrix respectively. Physical, mechanical, and morphological characterizations of fabricated WPCs were then carried out to analyse their properties. Morphological properties of composites samples were analyzed through scanning electron microscopy (SEM). The result reveals that in-situ wood composite exhibited better properties compared to pure wood, 5% WPC and 20% WPC. Moreover, in-situ WPC had lowest water absorption and least biodegraded. Conversely, pure wood shown moderate mechanical strength, high biodegradation and water absorption rate. In term of biodegradation, earth-medium brought more severe effect than water in deteriorating the properties of the specimens

Generalized Spin Coherent States: Construction and Some Physical Properties

International Nuclear Information System (INIS)

Berrada, K.; El Baz, M.; Hassouni, Y.

2009-12-01

A generalized deformation of the su(2) algebra and a scheme for constructing associated spin coherent states is developed. The problem of resolving the unity operator in terms of these states is addressed and solved for some particular cases. The construction is carried using a deformation of Holstein-Primakoff realization of the su(2) algebra. The physical properties of these states is studied through the calculation of Mandel's parameter. (author)

Some thermo-physical properties of yam cuts of two geometries ...

African Journals Online (AJOL)

The effects of variation of temperature (-18 to 33°C) and geometries (slab and cylinder) on some thermo-physical properties of white yam were investigated. The measured parameters were density, specific heat, and thermal diffusivity at constant moisture level of 72.7% ± 0.69 (wet basis) using transient heat transfer method ...

The relation of autonomic function to physical fitness in patients suffering from alcohol dependence.

Science.gov (United States)

Herbsleb, Marco; Schulz, Steffen; Ostermann, Stephanie; Donath, Lars; Eisenträger, Daniela; Puta, Christian; Voss, Andreas; Gabriel, Holger W; Bär, Karl-Jürgen

2013-10-01

Reduced cardio-vascular health has been found in patients suffering from alcohol dependence. Low cardio-respiratory fitness is an independent predictor of cardio-vascular disease. We investigated physical fitness in 22 alcohol-dependent patients 10 days after acute alcohol withdrawal and compared results with matched controls. The standardized 6-min walk test (6 MWT) was used to analyze the relationship of autonomic dysfunction and physical fitness. Ventilatory indices and gas exchanges were assessed using a portable spiroergometric system while heart rate recordings were obtained separately. We calculated walking distance, indices of heart rate variability and efficiency parameters of heart rate and breathing. In addition, levels of exhaled carbon monoxide were measured in all participants to account for differences in smoking behaviour. Multivariate analyses of variance (MANOVA) were performed to investigate differences between patients and controls with regard to autonomic and efficiency parameters. Patients walked a significantly shorter distance in comparison to healthy subjects during the 6 MWT. Significantly decreased heart rate variability was observed before and after the test in patients when compared to controls, while no such difference was observed during exercise. The efficiency parameters indicated significantly reduced efficiency in physiological regulation when the obtained parameters were normalized to the distance. The 6 MWT is an easily applied instrument to measure physical fitness in alcohol dependent patients. It can also be used during exercise interventions. Reduced physical fitness, as observed in our study, might partly be caused by autonomic dysfunction, leading to less efficient regulation of physiological processes during exercise. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

influence of tillage practices on physical properties of a sandy loam

African Journals Online (AJOL)

DR. AMINU

many regions of the world if the mechanics of tillage effects on soil physical properties is to be well understood. Thus, the ... tillage systems on water storage of a sandy loam soil after 22 years of ..... Soil infiltration ... and processes. Academy ...

Hanford Waste Physical and Rheological Properties: Data and Gaps - 12078

Energy Technology Data Exchange (ETDEWEB)

Kurath, D.E.; Wells, B.E.; Huckaby, J.L.; Mahoney, L.A.; Daniel, R.C.; Burns, C.A.; Tingey, J.M.; Cooley, S.K. [Pacific Northwest National Laboratory PO Box 999, Richland WA 99352 (United States)

2012-07-01

The retrieval, transport, treatment and disposal operations associated with Hanford Tank Wastes involve the handling of a wide range of slurries. Knowledge of the physical and rheological properties of the waste is a key component to the success of the design and implementation of the waste processing facilities. Previous efforts to compile and analyze the physical and rheological properties were updated with new results including information on solids composition and density, particle size distributions, slurry rheology, and particle settling behavior. The primary source of additional data is from a recent series of tests sponsored by the Hanford Waste Treatment and Immobilization Plant (WTP). These tests involved an extensive suite of characterization and bench-scale process testing of 8 waste groups representing approximately 75% of the high-level waste mass expected to be processed through the WTP. Additional information on the morphology of the waste solids was also included. Based on the updated results, a gap analysis to identify gaps in characterization data, analytical methods and data interpretation was completed. (authors)

Interfacial effect on physical properties of composite media: Interfacial volume fraction with non-spherical hard-core-soft-shell-structured particles.

Science.gov (United States)

Xu, Wenxiang; Duan, Qinglin; Ma, Huaifa; Chen, Wen; Chen, Huisu

2015-11-02

Interfaces are known to be crucial in a variety of fields and the interfacial volume fraction dramatically affects physical properties of composite media. However, it is an open problem with great significance how to determine the interfacial property in composite media with inclusions of complex geometry. By the stereological theory and the nearest-surface distribution functions, we first propose a theoretical framework to symmetrically present the interfacial volume fraction. In order to verify the interesting generalization, we simulate three-phase composite media by employing hard-core-soft-shell structures composed of hard mono-/polydisperse non-spherical particles, soft interfaces, and matrix. We numerically derive the interfacial volume fraction by a Monte Carlo integration scheme. With the theoretical and numerical results, we find that the interfacial volume fraction is strongly dependent on the so-called geometric size factor and sphericity characterizing the geometric shape in spite of anisotropic particle types. As a significant interfacial property, the present theoretical contribution can be further drawn into predicting the effective transport properties of composite materials.

Material designs and new physical properties in MX- and MMX-chain compounds

CERN Document Server

Yamashita, Masahiro

2014-01-01

This book details the structures, physical properties, theoretical treatments, applications, and perspectives of MX and MMX chain compounds for chemists and physicists. It also examines various photoinduced phase transitions and their dynamics.

Density-dependent effects on physical condition and reproduction in North American elk: an experimental test.

Science.gov (United States)

Kelley M. Stewart; R. Terry Bowyer; Brian L. Dick; Bruce K. Johnson; John G. Kie

2005-01-01

Density dependence plays a key role in life-history characteristics and population ecology of large, herbivorous mammals. We designed a manipulative experiment to test hypotheses relating effects of density-dependent mechanisms on physical condition and fecundity of North American elk (Cervus elaphus) by creating populations at low and high density...