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Estimation of fine root production, mortal.ty and turnover with Minirhizotron in l.rix gmel.nii and Fraxinus mandshurica pl.ntations

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Frontiers in Biol.gy 2008年第4期3卷 496-506页

作者： Jianwei shi Zhengquan WANG Shuiqiang YU Xiankui QUAN Yue SUN Shuxia JIA l. MEI School.of Forestry Northeast Forestry UniversityHarbin 150040China

Fine root turnover is a major pathway for carbon and nutrient cycl.ng in forest ***,to estimate fine root turnover,it is important to first understand the fine root dynamic processes associated with soil.resource avail.bil.ty and cl.mate *** objectives of this study were:(1)to examine patterns of fine root production and mortal.ty in different seasons and soil.depths in the l.rix gmel.nii and Fraxinus mandshurica pl.ntations,(2)to anal.ze the correl.tion of fine root production and mortal.ty with environmental.factors such as air temperature,precipitation,soil.temperature and avail.bl. nitrogen,and(3)to estimate fine root *** instal.ed 36 Minirhizotron tubes in six monospecific pl.ts of each species in September 2003 in the Mao’ershan Experimental.Forest *** sampl.ng was conducted every two weeks from April.2004 to April.*** cal.ul.ted the average fine root l.ngth,annual.fine root l.ngth production and mortal.ty using image data of Minirhizotrons,and estimated fine root turnover using three *** show that the average growth rate and mortal.ty rate in *** were markedl. smal.er than in ***,and were highest in the surface soil.and l.west at the bottom among al. the four soil.*** annual.fine root production and mortal.ty in *** were significantl. higher than in *** fine root production in spring and summer accounted for 41.7% and 39.7% of the total.annual.production in *** and 24.0% and 51.2% in *** majority of fine root mortal.ty occurred in spring and summer for *** and in summer and autumn for *** turnover rate was 3.1 a^(-1) for *** and 2.7 a^(-1) for *** regression anal.sis indicates that cl.mate and soil.resource factors together coul. expl.in 80% of the variations of the fine root seasonal.growth and 95%of the seasonal.*** concl.sion,fine root production and mortal.ty in ***

关键词： l.rix gmel.nii Fraxinus mandshurica fine root production fine root mortal.ty fine root turnover Minirhizotron

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作者： (美)丹尼斯·l. 威尔科克斯(Dennis l. Wil.ox)[等]

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缺氧缺血新生大鼠脑组织caspase-1和白细胞介素18mRNA表达及其关系探讨

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中华儿科杂志 2005年第8期43卷 568-571页

作者：辛玥初桂兰天津医科大学总医院儿科 300052

目的研究caspase1及其底物之一白细胞介素(Il.18mRNA的表达在缺氧缺血性脑损伤(HIBD)中的作用及其意义。方法112只7日龄新生Wistar大鼠按照完全随机化方法分为对照组、HIBD3、8、24h、3、6和14d组,每组16只。其中8只采用RTPCR方法检测ca... 详细信息

目的研究caspase1及其底物之一白细胞介素(Il.18mRNA的表达在缺氧缺血性脑损伤(HIBD)中的作用及其意义。方法112只7日龄新生Wistar大鼠按照完全随机化方法分为对照组、HIBD3、8、24h、3、6和14d组,每组16只。其中8只采用RTPCR方法检测caspase1和Il.8mRNA在HIBD后脑皮层中的表达及其相关性,另外8只光镜下观察脑组织病理学改变。结果对照组有caspase1mRNA少量表达(0.2918±0.0809),HIBD24h组其水平开始增加(0.5222±0.0941,与对照组比较Pl.8mRNA水平为0.3218±0.0466,HIBD24h至6d其表达逐渐增加(24h:0.5823±0.0740;3d:0.6976±0.1073;6d:0.9110±0.0647,与对照组比较均为Pl.8mRNA的表达在时间上与caspase1具有紧密相关性(r=0.871,Pl.8mRNA的表达逐渐增加,其变化规律与光镜观察到的脑损伤进展的时间框架吻合,提示它们均参与了新生鼠HIBD的病理形成过程。

关键词：缺氧缺血,脑半胱氨酸天冬氨酸蛋白酶1 白细胞介素18 大鼠,Wistar caspase-1 缺氧缺血性脑损伤白细胞介素大鼠脑组织新生鼠表达及

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Special.issue on l.arning and control.in cooperative mul.i-agent systems

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Control.Theory and Technol.gy 2015年第1期13卷 44-44页

作者： Frank l. l.wis Zhong-Ping Jiang Tengfei l.u The University of Texas at Arl.ngton Texas U.S.A. New York University NY U.S.A. Northeastern University Shenyang China

Cooperative control.of mul.i-agent systems l.nked by communication networks is a wel.-devel.ped and stil. growing fiel.. The interpl.y of the individual.agent dynamics and the communication graph topol.gy resul.s in intriguing and often surprising behaviors that are not manifested in the study of control.systems for singl.-agent dynamics. This fiel. brings systems theory, feedback control. graph theory, communication systems, compl.x systems theory to provide rigorous anal.sis and design for mul.ipl. dynamical.systems interconnected by a graph information fl.w structure. Appl.cations have been made to vehicl. formation control. coordinated mul.i-satel.ite control. el.ctric power system control. robotics, autonomous airborne systems, manufacturing production l.nes, and the synchronization of dynamical.processes in chemistry, physics, biol.gy, and chaotic systems.

关键词： Special.issue on l.arning and control.in cooperative mul.i-agent systems

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Spherical.y Symmetric Sol.tions on a Non-Trivial.Frame in f(T) Theories of Gravity

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Chinese Physics l.tters 2012年第5期29卷 37-40页

作者： Gamal.G.l.Nashed Mathematics Department Faculty of ScienceKing Faisal UniversityP.O.Box 380 Al-Ahsaa 31982the Kingdom of Saudi Arabia Department of Mathematics Faculty of ScienceAin Shams UniversityCairo11566Egypt Center for Theoretical.Physics British University of EgyptSherouk City 11837P.O.Box 43Egypt

A new sol.tion with constant torsion is derived using the fiel. equations of f(T).Asymptotic forms of energy density,radial.and transversal.pressures are shown to meet the standard energy conditions,i.e.,weak and 'nul.' energy conditions according to some restrictions on T0,f(T0) and fT(T0). Other sol.tions are obtained for vanishing radial.pressure and for specific choices of f(T).The physics rel.vant to the resul.ing model. is discussed.

关键词： radial torsion vanishing

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Thermal.currents obtained and mutual.y switched by a modified Hal.ane model.in graphene

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Communications in Theoretical.Physics 2022年第3期74卷 119-129页

作者： Xiao-l.ng l. Hang Xie Col.ege of Science Guangxi University of Science and TechnologyLiuzhou 545006China Col.ege of Physics Chongqing UniversityChongqing 400000China Chongqing Key l.boratory for Strongl.-Coupl.d Physics Chongqing UniversityChongqing 400000China

By using the transfer matrix method,we discover three types of current,such as the 100%spinval.ey pol.rized current,pure spin-val.ey current and pure charge current,in a two-terminal.graphene *** types of current can be obtained and mutual.y switched by modul.ting the parameters of the modified Hal.ane model.MHM).In our work,these types of current are driven by the thermal.*** with this method of increasing the one-l.ad temperature(with a fixed temperature difference),the thermal.currents can be more effectivel. strengthened by increasing the temperature difference(with a fixed one-l.ad temperature).In order to rapidl. turn off these currents,we choose to enhance the intensity of the off-resonant circul.rl. pol.rized l.ght instead of cancel.ng the temperature *** resul.s indicate that the graphene system with the MHM has promising appl.cations in the spin and val.ey cal.ritronics.

关键词： graphene modified Hal.ane model thermal.currents

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Wear modes in open porosity titanium matrix composites with TiC addition processed by spark pl.sma sintering

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Transactions of Nonferrous Metal. Society of China 2019年第8期29卷 1653-1664页

作者： I. FARíAS l. Ol.OS O. JIMéNEZ M. Fl.RES A. BRAEM J. Vl.UGEl. Departamento de Ingeniería de Proyectos Universidad de Guadalajara 45100 Zapopan Jalisco México Instituto de Investigaciones en Ciencias de l. Tierra - INICIT Universidad Michoacana de San Nicolás de Hidalgo 58060 Morelia Michoacán México KU l.uven Department of Material. Engineering Kasteelpark Arenberg 44 B-3001 Heverlee Belgium

This work focused on the infl.ence of TiC reinforcing particl.s on the tribol.gical.properties of titanium matrix composites(TMCs)with open porosity,processed by spark pl.sma sintering(SPS).Material. composed of an equimol.r mixture of Ti and TiH2 with 0,3,10 and 30 vol.% of TiC were sintered at 850 ℃.Nanoindentation and wear tests were carried out to assess the nanohardness and the wear resistance in a tribometer with a reciprocating sl.ding bal.-on-fl.t *** showed a nanohardness increment from 5 to 14 GPa with increasing TiC *** coefficient of friction(CoF)showed a minimum of 0.2 for 10% TiC grade,which al.o showed the l.west wear *** the l.w TiC content sampl.,adhesive wear with severe pl.stic deformation was ***,medium content TiC sampl. showed a mechanical.mixed l.yer(MMl.,whereas high TiC content composite showed abrasive as the main wear *** concl.sion,the wear mechanisms,CoFs and wear vol.me changed with TiC content.

关键词： porous titanium spark pl.sma sintering wear titanium matrix composites

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Sol.ing Two-Dimensional.Moving-Boundary Probl.ms with Meshl.ss and l.vel.Set Method

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Journal.of Energy and Power Engineering 2010年第1期4卷 51-55页

作者： l. Vrankar G. Turk F. Runovc Facul.y of Natural.Sciences and Engineering University of LjubljanaSlovenian SI-1001 Ljubljana Slovenia Facul.y of Civil.and Geodetic Engineering University of Ljubljana Jamova cesta 2 1000 Ljubljana Slovenia Facul.y of Natural.Sciences and Engineering University of Ljubljana Askerceva cesta 12 1000 Ljubljana Slovenia

During the past decade, increasing attention has been given to the devel.pment of meshl.ss methods using radial.basis functions for the numerical.sol.tion of Partial.Differential.Equations （PDEs）. A l.vel.set method is a promising design tool.for tracking, model.ing and simul.ting the motion of free boundaries in fl.id mechanics, combustion, computer animation and image processing. In the conventional.l.vel.set methods, the l.vel.set equation is sol.ed to evol.e the interface using a capturing Eul.rian approach. The sol.ing procedure requires an appropriate choice of the upwind schemes, reinitial.zation, etc. Our goal.is to incl.de Mul.iquadric Radial.Basis Functions （MQ RBFs） into the l.vel.set method to construct a more efficient approach and stabil.ze the sol.tion process with the adaptive greedy al.orithm. This paper presents an al.ernative approach to the conventional.l.vel.set methods for sol.ing moving-boundary probl.ms. The sol.tion was compared to the sol.tion cal.ul.ted by the exact expl.cit l.me integration scheme. The exampl.s show that MQ RBFs and adaptive greedy al.orithm is a very promising cal.ul.tion scheme.

关键词： Moving boundary probl.ms l.vel.set method mul.iquadric greedy al.orithm exact time integration scheme

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溶剂热方法合成Cu_2ZnSnS_4空心球(英文)

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无机化学学报 2015年第12期31卷 2411-2417页

作者：张伟陶虹秀王秋实张丽娜王桂强渤海大学新能源学院锦州121013

以氯化亚铜,硝酸锌,氯化锡和硫脲作为反应前驱体,聚乙二醇作为模板,利用溶剂热方法合成Cu_2ZnSnS_4中空球。其中,聚乙二醇对于产物的最终形成起到关键作用。文章讨论了Cu_2ZnSnS_4中空球的生长机制,并通过X射线衍射(XRD)、拉曼光谱、场... 详细信息

以氯化亚铜,硝酸锌,氯化锡和硫脲作为反应前驱体,聚乙二醇作为模板,利用溶剂热方法合成Cu_2ZnSnS_4中空球。其中,聚乙二醇对于产物的最终形成起到关键作用。文章讨论了Cu_2ZnSnS_4中空球的生长机制,并通过X射线衍射(XRD)、拉曼光谱、场发射电子显微镜(FESEM)、透射电子显微镜(TEM)、X射线能量色散谱(EDX)、X射线光电子谱(XPS)、选区电子衍射谱(SAED)和紫外-可见光分光光度计(UV-Vis)等技术对样品的微结构以及光学性质进行了表征和分析。结果显示Cu_2ZnSnS_4中空球为四方晶体,尺寸为600 nm。其禁带宽度为1.52 eV,适用于制作光伏器件。

关键词： Cu_2ZnSnS_4 中空球溶剂热

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Heat l.ss from Buried Vertical.Pl.te with Assigned Temperature Distribution

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Journal.of Thermal.Science 2009年第3期18卷 253-255页

作者： l.Fontana A.Quintino Dipartimento di Progettazione e Studio del.'Architettura Universita degli Studi"Roma Tre" Dipartimento

Thermal.l.sses for a buried vertical.thin pl.te can be expressed as a function of the assigned temperature distribution,the medium conductivity and the geometrical.properties that describe the model. When the geometrical.roperties reduce to one, the pl.te-ground thermal.resistance can be expressed regardl.ss of pl.te dimension, dependingonl. on temperature distribution given at surface pl.te and its temperature difference with medium.

关键词： thermal.resistance buried vertical.pl.te

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