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Biomedical and Environmental sciences 1999年第3期12卷 201-213页

作者： s·c·PANT R·VIJAYARAGHAVAN DivisionofpharmacologyandTcxicology DefenceResearchandDevelopmentEstablishmentJhansiRoadGwalior－4740

Toxic effects of inhaled sulfur mustard (sM) on the histology of visceral organs was investigaed by exposing mice to 84. 6mg/m3 for 1h duration, using controlled single exposure conditions. A progressive fall in body weight from third day onwards was noticed. Light microscopic examination of the pulmonary tissue of these animals at 6 h post exposure revealed that the tracheobronchial epithelium remained intact, but was infiltrated by inflammatory cells. By 24 h post exposure, the mucosecretory cells were destroyed. The indanunatory reaction was maximum at 48 h. By 7th day post exposure there was swelling and vacuolation of lung parenchymal cells and thrombi formation. In addition sM caused congestion and hemorrhage at alveolar level. sM also caused granulovacuolar degeneration with perinuclear clumping of the cytopasm of hepatocytes and renal parenchymal cells. Renallesions were chazacterized by congestion and hemorrhage. Among visceral tissues, maximum atrophywas observed in spleen. Distribution of lesions increased with post exposure period. The maximum lesions were observed at 7th day post-exposure.

关键词： Animals Dermatologic Agents Female Hemorrhage Inhalation Exposure Kidney Lung Mice Mustard Gas Time Factors Weight Loss

High-cycle Fatigue Life Extension of Glass Fiber/Polymer composites with carbon Nanotubes

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Journal of Wuhan University of Technology(Materials science) 2009年第2期24卷 167-173页

作者： christopher s Grimmer c K H Dharan Berkeley composites Laboratory University of California 5135 Etcheverry Hall Berkeley CA94720-1740 USA

The present work shows that the addition of small volume fractions of multi-walled carbon nanotubes （cNTs） to the matrix results in a significant increase in the high-cycle fatigue life. It is proposed that carbon nanotubes tend to inhibit the formation of large cracks by nucleating nano-scale damage zones. In addition, the contribution to energy absorption from the fracture of nanotubes bridging across nano-scale cracks and from nanotube pull-out from the matrix are mechanisms that can improve the fatigue life. An energy-based model was proposed to estimate the additional strain energy absorbed in fatigue. The distributed nanotubes in the matrix appear to both distribute damage as well as inhibit damage propagation resulting in an overall improvement in the fatigue strength of glass fiber composites.

关键词： glass fiber composites carbon nanotubes fatigue strain energy

Peristaltic transport of rheological fluid:model for movement of food bolus through esophagus

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Applied Mathematics and Mechanics(English Edition) 2012年第3期33卷 315-332页

作者： J.c.MIsRA s.MAITI Department of Mathematics Institute of Technical Education and ResearchSiksha 'O' Anusandhan UniversityBhubaneswar 751030India school of Medical science and Technology & center for Theoretical studies Indian Institute of TechnologyKharagpur 721302India

Fluid mechanical peristaltic transport through esophagus is studied in the paper. A mathematical model has been developed to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of a viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed specifically to explore some important information concerning the movement of food bolus through esophagus. The analysis is carried out by using the lubrication theory. The study is particularly suitable for the cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes place by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocities, particle trajectory, and reflux is investigated for a single wave as well as a train of periodic peristaltic waves. The locally variable pressure is seen to be highly sensitive to the flow index ＂n＂. The study clearly shows that continuous fluid transport for Newtonian/rheological fluids by wave train propagation is more effective than widely spaced single wave propagation in the case of peristaltic movement of food bolus in the esophagus.

关键词： non-Newtonian fluid food bolus esophagus peristaltic transport flow reversal single wave wave train particle trajectory

charged analogue of well behaved neutral spheres:an algorithmic approach

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chinese Physics c 2016年第4期40卷 34-42页

作者： s.Thirukkanesh F.c.Ragel Department of Mathematics Eastern UniversityChenkalady Sri Lanka Department of Physics Eastern UniversityChenkalady Sri Lanka

We establish a systematic algorithmic approach that generates new classes of solutions to the EinsteinMaxwell system in static spherically symmetric spacetime from well known uncharged solutions. A particular case is shown to satisfy all major physical features of a realistic charged star including the standard point-wise energy conditions of normal matter. The solution matches smoothly with the exterior Reissner-Nordstr¨om metric at the pressure free interface. The study, which is reported for a particular choice of gravitational potential, encourages similar approaches to study electrification of well known physically realistic uncharged models.

关键词： behaved realistic spheres matches symmetric smoothly satisfy exterior interior analogue

Experimental study of sand grains behavior at their contacts with force-and displacement-controlled sliding tests

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Underground space 2017年第1期2卷 38-44页

作者： K.senetakis c.s.sandeep city University of Hong Kong Hong Kong

Discrete element modeling requires the proper quantification of the behavior of grains at their contacts including the normal force-displacement and tangential force-displacement relationships to be used as input for contact modeling *** paper reports on recent advances in soil mechanics experimentation which allowed measuring the grain contact behavior of small sand particles quantifying friction and stiffness with sliding tests of a force-controlled or displacement-controlled *** particular focus of this work is on the micromechanical behavior of quartz type grains of size between about 1 and 5 mm.A description of the developed micromechanical apparatus at city University of Hong Kong is first discussed and its important different capabilities with previously developed apparatus is briefly ***,a limited set of new data is reported and discussed along with a review of recently acquired results published in the literature associated with the contact behavior of quartz sand *** sliding tests have covered a wider range of normal contact forces from about 0.5 to 8 N,and the results indicated that,for this range of confining forces,there is not any notable change of the inter-particle coefficient of friction.

关键词： Micro-mechanics Inter-particle friction Inter-particle stiffness LBs grains Experimental mechanics

Extraction of Nuclear Matter Properties from Nuclear Masses by a Model of Equation of state

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communications in Theoretical Physics 2001年第11期36卷 583-588页

作者： K.c.chung c.s.Wang A.J.santiago Instituto de Fisica Universidade do Estado do Rio de JaneiroRio de Janeiro-RJ 20559-900Brazil Instituto de FisicaUniversidade do Estado do Rio de JaneiroRio de Janeiro-RJ 20559-900Brazil Instituto de FisicaUniversidade do Estado do Rio de JaneiroRio de Janeiro-RJ 20559-900Brazil

The extraction of nuclear matter properties from measured nuclear masses is investigated in the energy density functional formalism of *** is shown that the volume energy a1 and the nuclear incompressibility Ko depend essentially on μnN -+- pZ - 2EN,whereas the symmetry energy J and the density symmetry coefficient L as well as symmetry incompressibility Ks depend essentially on μn - μp,where μp ＝μp - Ec/ Z,μn and μp are the neutron and proton chemical potentials respectively,EN the nuclear energy,and Ec the coulomb *** obtained symmetry energy is J ＝ 28.5 MeV,while other coefficients are uncertain within ranges depending on the model of nuclear equation of state.

关键词： nuclear matter properties,nuclear matter equation of state

Optical disassembly of cellular clusters by tunable ‘tug-of-war’ tweezers

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Light(science & Applications) 2016年第1期5卷 444-450页

作者： Anna s Bezryadina Daryl c Preece Joseph c chen Zhigang chen Department of Physics and Astronomy San Francisco State UniversitySan FranciscoCA 94132USA school of Mathematics and Physics The University of QueenslandBrisbaneQLD 4072Australia Department of NanoEngineering University of CaliforniaSan DiegoLa JollaCA 92093USA Department of Biology San Francisco State UniversitySan FranciscoCA 94132USA The MOE Key Laboratory of Weak-Light Nonlinear Photonics TEDA Applied Physical Institute and School of PhysicsNankai UniversityTianjin 300457China

Bacterial biofilms underlie many persistent infections,posing major hurdles in antibiotic *** we design and demonstrate‘tug-of-war’optical tweezers that can facilitate the assessment of cell–cell adhesion—a key contributing factor to biofilm development,thanks to the combined actions of optical scattering and gradient *** a customized optical landscape distinct from that of conventional tweezers,not only can such‘tug-of-war’tweezers stably trap and stretch a rod-shaped bacterium in the observing plane,but,more importantly,they can also impose a tunable lateral force that pulls apart cellular clusters without any tethering or mechanical *** a proof of principle,we examined a sinorhizobium meliloti strain that forms robust biofilms and found that the strength of intercellular adhesion depends on the growth *** technique may herald new photonic tools for optical manipulation and biofilm study,as well as other biological applications.

关键词： bacterial adhesion biofilm optical forces optical manipulation tug-of-war optical tweezers

Temperature and Thermal stress Distribution for Metal Mold in squeeze casting Process

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Journal of Materials science & Technology 2008年第3期24卷 347-350页

作者： c.H.Lee s.H.Lee Institute of Technology and science Chung-Ang University

In the squeeze casting process, loaded high pressure （over approximately 200 MPa） and high temperature influence the thermo-mechanical behavior and performance of the used metal mold. Therefore, to safely maintain the metal molds, the thermo-mechanical characteristics （temperature and thermal stress） of metal mold in the squeeze casting must be investigated. In this paper, temperature and thermal stress distribution of steel mold in squeeze casting process were investigated by using a three-dimensional non-steady heat conduction analysis and a three-dimensional thermal elastic-plastic analysis considering temperature-dependent thermophysical and mechanical properties of the steel mold.

关键词： squeeze casting steel mold Thermal stress Thermo-Mechanical analysis

Estimating REY content of eastern Kentucky coal samples based on their associated ash elements

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Journal of Rare Earths 2018年第11期36卷 1234-1238页

作者： s.chehreh chelgani James c.Hower Department of Electrical Engineering and computer science University of Michigan center for Applied Energy Research University of Kentucky

coal and coal combustion byproducts can be considered as an alternative source of rare earth elements and yttrium （REY）. The study of relationships between REY and other main coal properties could have several advantages such as estimating REY content of coal particles and designing beneficial extraction method. In this investigation, inter-correlations between REY content with coal parameters （proximate and ash elements） for a wide range of eastern Kentucky coal samples （708 records） were explored. Results demonstrate that zircon and monazite are the main source of heavy and light rare earth elements （HREE and LREE）, respectively. Zr has the highest correlation with Y and Th has the strength relationship with ce and La. In general, LREE have higher interaction with coal ash content in comparison with HREE. Results indicated that REY can be estimated quite satisfactorily by using their associated elements in coal ash.

关键词： coal Heavy rare earth Light rare earth Proximate Ash elements

Effects of mechanical vibration on the physical,metallurgical and mechanical properties of cast A308(LM21)aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2022年第6期29卷 1206-1215页

作者： siddharth Yadav s.P.Tewari J.K.singh s.c.Ram Department of Mechanical Engineering Indian Institute of Technology(BHU)Varanasi 221005India Department of Metallurgical Engineering Indian Institute of Technology(BHU)Varanasi 221005India

This study investigated the microstructure,physical,and mechanical properties of die-cast A308 alloy subjected to mechanical vibration during *** frequencies(0,20,30,40,and 50 Hz)at constant amplitude(31μm)were employed using a power amplifier as the power input device.X-ray diffraction,optical microscopy,and scanning electron microscopy were used to examine the morphological changes in the cast samples under stationary and vibratory *** features of the castings were evaluated using Image J *** average values of metallurgical features,including primaryα-Al grain size,dendrite arm spacing,average area of eutectic silicon,aspect ratio,and percentage porosity,reduced by 34%,59%,56%,22%,and 62%,respectively,at 30 Hz frequency compared with stationary *** tests of the cast samples showed that the yield strength(Ys),ultimate tensile strength(UTs),percentage elongation(%EL),and microhardness(HV)increased by 8%,13%,17%,and 16%,respectively,at 30 Hz frequency compared with stationary *** fractured surface of the tensile specimens exhibited mixed-mode fracture behavior because of brittle facets,cleavage facets,ductile tearing,and dimple *** presence of small dimples showed that plastic deformation occurred before fracture.

关键词： mechanical vibration microstructures microhardness tensile strength fractography