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Communications in Theoretical Physics 2016年第8期65卷 237-243页

作者： M.Mobaraki s.Jafari Department of Physics University of Guilan

In this paper, the nonlinear interaction of ultra-high power laser beam with fusion plasma at relativistic regime in the presence of obliquely external magnetic field has been studied. Imposing an external magnetic field on plasma can modify the density profile of the plasma so that the thermal conductivity of electrons reduces which is considered to be the decrease of the threshold energy for ignition. To achieve the fusion of Hydrogen–Boron(HB) fuel,the block acceleration model of plasma is employed. Energy production by HB isotopes can be of interest, since its reaction does not generate radioactive tritium. By using the inhibit factor in the block model acceleration of plasma and Maxwell's as well as the momentum transfer equations, the electron density distribution and dielectric permittivity of the plasma medium are obtained. Numerical results indicate that with increasing the intensity of the external magnetic field, the oscillation of the laser magnetic field decreases, while the dielectric permittivity increases. Moreover, the amplitude of the electron density becomes highly peaked and the plasma electrons are strongly bunched with increasing the intensity of external magnetic field. Therefore, the magnetized plasma can act as a positive focusing lens to enhance the fusion process. Besides, we find that with increasing θ-angle(from oblique external magnetic field) between 0 and 90°, the dielectric permittivity increases, while for θ between 90° and 180°, the dielectric permittivity decreases with increasing θ.

关键词：激光等离子体相互作用外部磁场激光聚变放射性电子密度分布非线性相互作用介电常数应用

A method for groundwater prospect zonation in data poor areas using remote sensing and GIs:a case study in Kalikavu Panchayath of Malappuram district,Kerala,India

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International Journal of Digital Earth 2009年第2期2卷 155-170页

作者： B.C.Thomas s.L.Kuriakose s.K.Jayadev school of Geography University of SouthamptonUK United Nations University-ITC school for Disaster Geo-information Management International Institute for Geo-information Science and Earth Observation(ITC)EnschedeThe Netherlands University Library University of KeralaPalayamThiruvananthapuramKeralaIndia

The present study was an attempt to delineate potential groundwater zones in Kalikavu Panchayat of Malappuram district,Kerala,*** geo-spatial database on geomorphology,landuse,geology,slope and drainage network was generated in a geographic information system(GIs)environment from satellite data,survey of India topographic sheets and field *** understand the movement and occurrence of groundwater,the geology,geomorphology,structural set-up and recharging conditions have to be well *** the present study,the potential recharge areas are delineated in terms of geology,geomorphology,land use,slope,drainage pattern,*** thematic data generated were integrated using a heuristic method in the GIs domain to generate maps showing potential groundwater *** composite output map scores were reclassified into different zones using a decision *** final output map shows different zones of groundwater prospect,viz.,very good(15.57%of the area),good(43.74%),moderate(28.38%)and poor(12.31%).Geomorphic units such as valley plains,valley fills and alluvial terraces were identified as good to excellent prospect zones,while the gently sloping lateritic uplands were identified as good to moderate *** sloping hilly terrains underlain by hard rocks were identified as poor groundwater prospect zones.

关键词： groundwater Kerala GIs satellite images geomorphic units land use heuristic methods prospect zones the Western Ghats

IMEX Evolution of scalar Fields on Curved Backgrounds

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Communications in Computational Physics 2009年第10期6卷 1063-1094页

作者： s.R.Lau H.P.Pfeiffer J.s.Hesthaven Division of Applied Mathematics Brown UniversityProvidenceRI 02912USA Theoretical Astrophysics and Relativity Group 130-33 California Institute of TechnologyPasadenaCA 91125USA Also at the Department of Mathematics and statistics University of New MexicoAlbuquerqueNM 87131USA.

Inspiral of binary black holes occurs over a time-scale of many orbits,far longer than the dynamical time-scale of the individual black *** evolutions of a binary system therefore require excessively many time-steps to capture interesting *** present a strategy to overcome the Courant-Friedrichs-Lewy condition in such evolutions,one relying on modern implicit-explicit ODE solvers and multidomain spectral methods for elliptic *** analysis considers the model problem of a forced scalar field propagating on a generic curved ***,we encounter and address a number of issues pertinent to the binary black hole problem in full general *** to the schwarzschild geometry in Kerrschild coordinates,we document the results of several numerical experiments testing our strategy.

关键词： Implicit-explicit schemes spectral methods numerical relativity black holes

Feed intake pattern of broiler chickens under intermittent lighting:Do birds eat in the dark?

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Animal Nutrition 2019年第2期5卷 174-178页

作者： Inês Rodrigues Mingan Choct school of Environmental and Rural science University of New England

This paper reflects the results of a short experiment conducted in parallel with a larger trial which aimed to test the assumption that ’consumption of feed by broiler chickens during periods of darkness is largely negligible’. To that effect, on d 31, feeders of birds raised under intermittent lighting(IL), i.e. 1 h of light[1L]:3 h of dark(3D):1L:3D:1L:3D:1L:3D:2L:6D, were weighed at the onset and at the end of each period of darkness(or scotoperiod). Moreover, in order to compare the feeding behavior of IL birds with that of broilers raised under continuous lighting(CL, i.e, 18L:6D), their feeders were weighed in parallel and at the same time points. On d 31, feed intake of IL birds during scotoperiods represented 45% of their 24 h feed intake. Both CL and IL birds presented anticipatory feed intake prior to the long nocturnal period of darkness(6D), as well as higher feed intake right at the onset of lighting at 06:00. Feed intake of CL birds during the 6D nocturnal scotoperiod was negligible at around 2% of their total feed intake. Intermittent lighting birds exhibited excitement at the start of each hour-length scotoperiod and, within that time,ingested around 2.5 times the amount of feed ingested by CL birds. Although short, this study revealed several interesting observations which might be worth further exploring in a larger, lengthier, behaviorfocused experiment. Amongst other factors, it might be interesting to understand whether the high feed intake observed during scotoperiods for IL birds in reflective of the whole flock or rather a coping mechanism developed mainly by hierarchically lower-ranking birds to achieve their daily feed intakes requirements.

关键词： Feeding behavior Lighting program Photoperiod scotoperiod

An Interface-Capturing Method for Resolving Compressible Two-Fluid Flows with General Equation of state

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Communications in Computational Physics 2009年第10期6卷 1137-1162页

作者： T.s.Lee J.G.Zheng s.H.Winoto Department of Mechanical Engineering National University of SingaporeSingapore 119260

In this study,a stable and robust interface-capturing method is developed to resolve inviscid,compressible two-fluid flows with general equation of state(EOs).The governing equations consist of mass conservation equation for each fluid,momentum and energy equations for mixture and an advection equation for volume fraction of one fluid *** of pressure equilibrium across an interface is used to close the model ***-Hancock scheme is extended to construct input states for Riemann problems,whose solutions are calculated using generalized HLLC approximate Riemann *** mesh refinement(AMR)capability is built into hydrodynamic *** resulting method has some ***,it is very stable and robust,as the advection equation is handled ***,general equation of state can model more materials than simple EOss such as ideal and stiffened gas EOss for *** addition,AMR enables us to properly resolve flow features at disparate ***,this method is quite simple,time-efficient and easy to implement.

关键词： MUsCL-Hancock scheme adaptive mesh refinement compressible two-fluid flows general equation of state

Natural rubber and the Russian dandelion genome

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National science Review 2018年第1期5卷 88-89页

作者： Brandon s.Gaut Department of Ecology and Evolutionary Biology University of California

The world needs *** is crucial for the tires on the cars,trucks and airplanes that propel modern *** is equally important for daily tasks:latex gloves in the lab,balloons in angioplasty and wetsuits that warm a cold dip in the *** can be made synthetically from petroleum derivatives,but synthetic rubber is not as strong as rubber isolated from *** principal plant source for natural rubber

关键词： Natural rubber and the Russian dandelion genome

Generation of passively Q-switched fiber laser at 1 μm by using Mosse as a saturable absorber

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Chinese Optics Letters 2017年第2期15卷 15-19页

作者： H. Ahmad s. A. Reduan s. N. Aidit Z. C. Tiu Photonics Research Centre University of Malaya Kuala Lumpur 50603 Malaysia

Passively Q-switched ytterbium-doped fiber lasers （YDFLs） incorporating a molybdenum sulfide selenide （Mosse）-based saturable absorber （sA） are demonstrated. The modulation depth and saturation intensity of the Mosse-based sA are measured to be approximately 25.0% and 0.002 MW/cm^2, respectively, using the twin detector technique. The YDFL＇s output has a center wavelength of 1038.5 nm with a top pulse width and energy of 1.2 μs and 18.9 nJ, respectively, at a pump power of 333 mW. The Mosse-based sA has a good linear optical response, providing significant opportunity for use in applications over an ultra-broadband spectrum, particularly spectroscopy and biomedical diagnostics.

关键词： Mo Generation of passively Q-switched fiber laser at 1 m by using Mo sse as a saturable absorber sA

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成人肥胖食养指南

中国实用乡村医生杂志 2024年第3期31卷 1-3,7页

作者：中华人民共和国国家卫生健康委员会中华人民共和国国家卫生健康委员会

肥胖是一种慢性代谢性疾病,近些年来,全球超重和肥胖率正快速增长,已成为威胁人类健康的严重问题。根据《中国居民营养与慢性病状况报告(2020年)》显示,我国18岁及以上居民超重率、肥胖率分别为34.3%、16.4%,其中18~44岁、45~59岁和60... 详细信息

肥胖是一种慢性代谢性疾病,近些年来,全球超重和肥胖率正快速增长,已成为威胁人类健康的严重问题。根据《中国居民营养与慢性病状况报告(2020年)》显示,我国18岁及以上居民超重率、肥胖率分别为34.3%、16.4%,其中18~44岁、45~59岁和60岁及以上居民肥胖率分别为16.4%、18.3%和13.6%,我国居民肥胖率呈上升趋势。肥胖不但导致较高的过早死亡风险,还与各种慢性非传染性疾病的发生相关,包括2型糖尿病、脑卒中、冠心病、高血压、呼吸系统疾病、骨关节炎和胆结石等。肥胖甚至还与多种肿瘤的发生相关。

关键词：慢性非传染性疾病骨关节炎成人肥胖肥胖率慢性代谢性疾病呼吸系统疾病胆结石 2型糖尿病

Gas Diffusion in Bi-disperse Porous Catalyst Pellets

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Chinese Journal of Chemical Engineering 2005年第4期13卷 471-476页

作者：刘秀凤张宝泉 LIN Y.s school of Chemical Engineering and Technology Tianjin University Department of Chemical and Materials Engineering Arizona State University Tempe AZ 85287 USA

A flux equation of diffusion for bi-disperse porous catalyst pellets was proposed by modifying the previously developed model equation over fractal trajectories. The proposed fractal model equation considered the same tortuous degree for both micro-and macro-pores. The experimental data of diffusion over a bi-disperse Ni/gamma-alumina pellet were obtained with a standard Wicke-Kallenbach diffusion cell for both carbon monoxide- ethylene and carbon dioxide-ethylene binary mixtures. The fitting between experimental results and the fractal model equation leads to a fractal dimension of 1.11. The prediction of diffusion flux over the bi-disperse Ni/gamma- alumina pellet by the proposed fractal model equation is much better than the traditional tortuosity-based model equation by comparison with the measured flux through the pellet.

关键词：双分散多孔催化剂气体扩散孔隙率有效扩散孔结构

Bridging the gap between research and schematic design phases in teaching architectural graduation projects

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Frontiers of Architectural Research 2020年第1期9卷 82-105页

作者： Eman s.AboWardah Architectural Engineering Department Prince Sultan UniversityRiyadh 11586Saudi Arabia Architectural Engineering Department Tanta UniversityTanta 31512Egypt

The architectural design studio course is generally considered the backbone of any architectural curriculum and follows a particular method of problem solving,which makes it a distinctive *** projects in most of the architectural programs are divided into two main phases,namely,research and project *** generate many findings from the research phase that are considered *** research problem emerges when students finish writing the research thesis,and most face difficulty in translating the collected data into actions to engage the initial idea of the ***,this study aims to high-light the transitional stage between the research and schematic design phases,which is described in this study as the"predesign bridging phase."The goal is to propose a practical strategy for bridging the gap between the research and schematic design phases to facilitate derivation of the design concept from different output variables to enable the creation of a suitable architectural morphological *** study adopts two research *** is proposing a new pedagogical framework and applying it to the architectural graduation design studio at Prince sultan University in Riyadh,saudi *** other is conducting a survey among students to evaluate the efficiency of the proposed framework in helping them bridge the gap between the research and schematic design *** and inferential statistics analysis methods are used to analyze the research data and study the correlation between the reflection of the new applied framework in the predesign bridging phase and the students'satisfaction toward the final projects'product and performance in the final *** study ends with a conclusion on how the applied teaching strategies facilitate the project starting point and raises the importance of proposing and testing new assessment strategies that are suitable for each phase in the graduation design studio.

关键词： Predesign bridging phase Graduation project Problem solving Mind mapping student self-criticism Peer criticism