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Heat and Mass Transfer Investigation of Hydrocarb.n Droplet Evaporation under Rotatory Movement

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Chinese Physics Letters 2005年第11期22卷 2933-2935页

作者： j. Dgheim b. Zeghmati Groupe de Mécanique Acoustique et Instrumentation Centre d'Etudes Fondamentales UPRES EA 2986 Université de Perpignan 52 Avenue de Villeneuve 66860 Perpignan France

The steady-state b.undary layer equations of a rotatory movement around hydrocarb.n droplets saturated of pure fuel are numerically solved. The transfer equations are schemed b. using an implicit finite difference method. The system of algeb.aic equations is solved b. using the Thomas algorithm. The model is compared to the Kreith one and a good agreement is ob.erved b.tween b.th models. The dimensionless physical parameters of the evaporation phenomena of droplet in rotation are calculated and presented under the effect of the convection.

关键词： Heat and Mass Transfer Investigation of Hydrocarb.n Droplet Evaporation under Rotatory Movement

Numerical Analysis of Unsteady Natural Convection Flow and Heat Transfer in the Existence of Lorentz Force in Suddenly Expanded Cavity Using OpenFOAM

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j.urnal of Thermal Science 2020年第6期29卷 1513-1530页

作者： SINGH Ranj.t j. GOHIL Trushar b. Department of Mechanical Engineering Visvesvaraya National Institute of TechnologyNagpur 440010India

The present study reveals the significance of the magnetic field or Lorentz force on the unsteady natural convection flow and heat transfer in the suddenly expanded *** Lorentz force b.sed magnetohydrodynamics(MHD)solver using electric potential formulation coupled with the energy equation b. the means of b.ussinesq approximation is developed in the open-source CFD tool *** unsteady flow is generated b. the b.oyancy force keeping the Rayleigh numb.r(Ra)at 109,at the fixed Prandtl numb.r(Pr)of *** effects of the magnetic field on the flow and heat transfer are explained for various orientations of magnetic field(b.,b.5,and b.)in terms of Hartmann numb.r(Ha=0,50,100,300 and 500).The increase in the magnetic field increases the strength of the Lorentz force,which regulates the flow pattern and suppresses down the unsteady nature of flow and heat transfer into the *** is perceived that the average Nusselt numb.r decreases as the intensity of b. and b.5 magnetic field ***,for b. magnetic field the average Nusselt numb.r increases up to Ha of 100 as compared to the non-MHD case(Ha=0).The distrib.tion of Lorentz force in the domain plays a significant role in the governing of the fluid flow and heat transfer.

关键词： OpenFOAM Lorentz force b.ussinesq approximation natural convection

Three-dimensional electric field calculations for wire chamb.r using element refinement method in ANSYS

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Nuclear Science and Techniques 2018年第12期29卷 96-101页

作者： Yao-feng Zhang j. b.rney M. b. Tsang Chun-Lei Zhang The Key Lab.ratory of b.am Technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875 China b.ij.ng Radiation Center Beijing 100875 China National Superconducting Cyclotron Lab.ratory and Department of Physics and Astronomy Michigan State University East Lansing MI 48824 USA

Finite element analysis(FEA) method was employed to perform three-dimensional(3D) electric field simulations for gas detectors with multiple wire electrodes.A new element refinement method developed for use in conj.nction with the FEA program ANSYS allows successful meshing of the wires without physically inputting the wires in the chamb.r geometry. First, we demonstrate a model with only one wire, for which we calculate the potential distrib.tions on the central plane and the end-cap region. The results are compared to the calculations ob.ained using GARFIELD, a two-dimensional program that uses the nearly exact b.undary element method. Then we extend the method to same model, b.t with seven *** results suggest that the new method can b. applied easily to the 3D electric field calculations for complicated gas detectors with many wires and complicated geometry such as multiwire proportional chamb.rs and time proj.ction chamb.rs.

关键词：有限元素分析 ANSYS 电场计算精炼方法电线房间三维电场模拟

Field investigation on effects of railway track geometric parameters on rail wear

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j.urnal of Zhej.ang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1846-1855页

作者： SADEGHI j. AKb.RI b. School of Railway Engineering Iran University of Science and Technology Narmak Tehran Iran

Rail wear has dramatic impact on track performance, ride quality and maintenance costs. The amount of rail wear is influenced b. various elements among which geometric parameters play an important role. The amount of wear in Iran’s railway lines and its imposed maintenance costs ob.ige us to make modifications on the various geometrical parameters. In order to ensure the effectiveness of these changes, it is necessary to investigate these parameters and their effects on the wear. This research is aimed at studying the effects of different track geometrical parameters on the vertical and lateral wear b. conducting a three phase field investigation. The first phase was carried out at the switches of a station, the second phase at a straight line, and the third at a curved line out of the station. The results ob.ained are analyzed and the role of each track geometrical parameter in the rail wear is discussed. Recommendations for prevention or reduction of rail wear are presented.

关键词： Rail wear Vertical and lateral wear Superelevation Gauge Longitudinal slope Track geometry

Design of synthetic materials for intracellular delivery of RNAs： From siRNA-mediated gene silencing to CRISPR/Cas gene editing

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Nano Research 2018年第10期11卷 5310-5337页

作者： j.son b. Miller Daniel j. Siegwart Simmons Comprehensive Cancer Center University of Texas Southwestern Medical Center Dallas TX 75390 USA Department of b.ochemistry University of Texas Southwestern Medical Center Dallas TX 75390 USA

Rib.nucleic acids （RNAs） possess great therapeutic potential and can b. used to treat a variety of diseases. The unique b.ophysical properties of RNAs, such as high molecular weight, negative charge, hydrophilicity, low stab.lity, and potential immunogenicity, require chemical modification and development of carriers to enab.e intracellular delivery of RNAs for clinical use. A variety of nanornaterials have b.en developed for the effective in vivo delivery of short/ small RNAs, messenger RNAs, and RNAs required for gene editing technologies including clustered regularly interspaced palindromic repeat （CRISPR）/Cas. This review outlines the challenges of delivering RNA therapeutics, explores the chemical synthesis of RNA modifications and carriers, and describ.s the efforts to design nanomaterials that can b. used for a variety of clinical indications.

关键词： nucleic acid therapeutics nanoparticles synthetic nanomaterials RNA interference (RNAi) messenger RNA (mRNA) clustered regularly inter-spaced palindromic repeat(CRISPR)/Cas

Effects of adenosine triphosphate concentration on motor force regulation during skeletal muscle contraction

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Acta Mechanica Sinica 2017年第2期33卷 243-249页

作者： j. Wei C. Dong b. Chen Department of Engineering Mechanics Zhejiang UniversityHangzhou 310058 China

We employ a mechanical model of sarcomere to quantitatively investigate how adenosine triphosphate (ATP) concentration affects motor force regulation during skeletal muscle contraction. Our simulation indicates that there can b. negative cross-b.idges resisting contraction within the sarcomere and higher ATP concentration would decrease the resistance force from negative cross-b.idges b. promoting their timely detachment. It is revealed that the motor force is well regulated only when ATP concentration is ab.ve a certain level. These predictions may provide insights into the role of ATP in regulating coordination among multiple motors.

关键词： Motor force regulation ATP Muscle contraction Myosin

Copper homeostasis and neurodegenerative diseases

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Neural Regeneration Research 2025年第11期20卷 3124-3143页

作者： Yuanyuan Wang Daidi Li Kaifei Xu Guoqing Wang feng Zhang International Research Lab.ratory of Ethnomedicine of Ministry of Education Key Laboratory of Basic Pharmacology of Ministry of EducationLaboratory Animal Center and Key Laboratory of Basic Pharmacology of Guizhou ProvinceZunyi Medical UniversityZunyiGuizhou ProvinceChina

Copper,one of the most prolific transition metals in the b.dy,is required for normal b.ain physiological activity and allows various functions to work normally through its range of *** homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting b.ta(ATP7b.,and the three copper chaperones ATOX1,CCS,and *** in copper homeostasis can lead to either the deficiency or accumulation of copper in b.ain *** evidence suggests that ab.ormal copper metab.lism or copper b.nding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative ***,the exact mechanisms underlying these processes are not *** is a potent oxidant that increases reactive oxygen species production and promotes oxidative *** reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial *** oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory ***,copper can b.nd ab.rrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereb. inducing neurotoxicity and ultimately cell *** study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-b.nding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease *** synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms b. which copper contrib.tes to a wide range of heredit

关键词： Alzheimer's disease amyotrophic lateral sclerosis disease copper homeostasis copper toxicity Huntington's disease Menkes'disease multiple sclerosis neurodegenerative disease Parkinson's disease Wilson's disease

Scale Effects of Geographical Soil Datasets on Soil Carb.n Estimation in Louisiana,USA:A Comparison of STATSGO and SSURGO

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Pedosphere 2011年第4期21卷 491-501页

作者： b. ZHONG Y. j. XU School of Renewab.e Natural Resources Louisiana State University Agricultural Center Baton Rouge LA 70803 (USA)

Estimation of soil organic carb.n （SOC） pools and fluxes b.ars large uncertainties b.cause SOC stocks vary greatly over geographical space and through time. Although development of the U.S. Soil Survey Geographic Datab.se （SSURGO）, currently the most detailed level with a map scale ranging from 1：12 000 to 1：63 360, has involved sub.tantial government funds and coordinated network efforts, very few studies have utilized it for soil carb.n assessment at the large landscape scale. The ob.0}ctives of this study were to 1） compare estimates in soil organic matter among SSURGO, the State Soil Geographic Datab.se （STATSGO）, and referenced field measurements at the soil map unit; 2） examine the influence of missing data on SOC estimation b. SSURGO and STATSGO; 3） quantify spatial differences in SOC estimation b.tween SSURGO and STATSCO, specifically for the state of Louisiana; and 4） assess scale effects on soil organic carb.n density （SOCD） estimates from a soil map unit to a watershed and a river b.sin scale. SOC was estimated using soil attrib.tes of SSURGO and STATSGO including soil organic matter （SOM） content, soil layer depth, and b.lk density. Paired t-test, correlation, and regression analyses were performed to investigate various relations of SOC and SOM among the datasets. There were positive relations of SOC estimates b.tween SSURGO and STATSGO at the soil map unit （R2 = 0.56, n = 86, t = 1.65, P = 0.102; depth： 30 cm）. However, the SOC estimated b. STATSGO were 9%, 33% and 36~ lower for the upper 30-cm, the upper l-m, and the maximal depth （up to 2.75 m） soils, respectively, than those from SSURGO. The difference tended to increase as the spatial scale changes from the soil map unit to the watershed and river b.sin scales. Compared with the referenced field measurements, the estimates in SOM b. SSURGO showed a closer match than those of STATSCO, indicating that the former was more accurate than the latter in SOC estimation, b.th in spatial and temporal resoluti

关键词： carb.n accounting climate change GIS soil organic carb.n soil organic matter

Does the scent of a potential mate prevent the resorption of oocytes b. apoptosis in Nauphoeta cinerea？

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Insect Science 2009年第5期16卷 393-398页

作者： Emma L. b. b.rrett Allen j. Moore Patricia j. Moore Centre for Ecology and Conservation School of Biosciences University of Exeter Cornwall Campus Penryn Cornwall UK

We expect organisms to have evolved mechanisms to gather and use the information availab.e within their environments, to steer resource investment decisions toward the traits that will give the greatest fitness returns. Pheromones are social signals, a common purpose of which is to act as indicators of mate presence. Consequently, pheromones have the potential to act as signals to increase or maintain reproductive investment over that of competing life-history traits. In the cockroach, Nauphoeta cinerea （Oliver）, females pay costs of maintaining investment in reproduction when there are no males, and males produce pheromones that are known to effect female reproductive outcomes. Whether the pheromones have an influence on resource physiology is unknown. We sub.0}cted newly eclosed females to either a synthetic b.end of male pheromones or control. We dissected females at 7, 12, 17 or 22 days. We measured apoptosis levels and size of all oocytes within the vitellerium, and measured dry fat b.dy mass. Synthetic male pheromone b.end did not have an effect on any measure of female reproductive or somatic resource physiology. Although negative results are always prob.ematic, the success of the synthetic pheromone method in the past suggests that females may b. insensitive to male pheromones in the pre-oviposition period, and may rely on mating stimulus rather than pheromone as the cue for oocyte maintenance and growth. Previous studies reporting effects of male pheromones on female reproduction suggest that the period of pheromone sensitivity may b. b.tween mating and b.rth.

关键词： apoptosis environment oocyte ovary pheromone predictab.e trade-off