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236篇 您的检索式:作者名="G.C."
    题名 作者 年代 出处 被引量
1美国心力衰竭住院患者的特点及预后:急性失代偿性心衰国家登记(ADHERE)研究的前10万病例中的原理、设计和初步观察Adams Jr. K.F. Fonarow G.C. Emerman C.L. 任付先 2005世界核心医学期刊文摘(心脏病学分册)2005,0,8:18
2Al_(80)Ni_6Y_8Co_4Cu_2 GLASS ALLOYS CONTAINING NANOSCALEPARTICLES BY ISOTHERMAL ANNEALING OR QUENCHING显示文摘Al80Ni6 Y8 Co4 Cu2 amorphous ribbons were isothermally annealed and a mixed structure consisting of α-Al particle with a size of less than 15nm and Al3Ni compound with a size of about 30nm was obtained. The crystallization kinetics of Al80Ni6 Y8 Co4 Cu2 amorphous alloy shows that the precipitation of α-Al particles is the growth process controlled by diffusion of the solute elements rejected from the growing crystals. By quenching at different cooling rates, a mixed structure consisting of nanoscale α-Al particles and the remaining glass matrix or structure consisting of nanoscale particle (Al phase or Al3Ni compound) with a size of about 100nm was formed. The addition of Co elements and Cu elements to Al-Ni-Y alloy systems increases the glass formation ability of the alloy and the thermal stability of the supercooled liquid region against crystallization, which results from significant difference of atomic size, strong bonding nature among constituent elements and the low diffisivity of the solute elements due to the concentration gradient in the growing front of crystals.Z. Bian, G. He and G.L. Chen (State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China) J. Lu, D.J. Chen, G.C. Tu, G.J. Chen and X.J. Hu (Shougang Metallurgical Research Institute, Beijing 2000Acta Metallurgica Sinica(English Letters)2000,13,5:16
3Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the Sichuan Basin, China显示文摘Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3-year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in Jianyang County, Sichuan Province, Southwestern China. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2) is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3) regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 21.5~41.0 % and 27.5~69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (34.41~331.67 % and 37.06~403.44 % for Plot 1 and Plot 2, respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3-year experiments.J.H. ZHANG Z.A. SU G.C. LIU 2008Journal of Mountain Science2008,5,3:16
4北京、西安和上海地区帕金森病的流行病学调查Roman G.C. 黄卫东 2005世界核心医学期刊文摘(神经病学分册)2005,0,7:14
5血吸虫对吡喹酮抗药性的研究 Ⅺ日本血吸虫中国大陆现场分离株虫卵毛蚴尾蚴对吡喹酮的敏感性显示文摘目的测定日本血吸虫中国大陆主要流行区现场分离株虫卵、毛蚴和尾蚴阶段对吡喹酮的敏感性,为建立日本血吸虫吡喹酮敏感性检测技术提供基础。方法分别从中国湖南、湖北、江西、安徽、江苏和云南6省日本血吸虫病流行区病人粪便标本中分离虫卵,建立日本血吸虫现场分离虫株;采用实验室已有的3株曼氏血吸虫株为对照。将各虫株虫卵分别孵育于5×10-6、10-6、5×10-7、10-7mol/L吡喹酮溶液中24h后移至清水孵化,观察虫卵的孵化率。将各虫株毛蚴分别暴露于5×10-6、10-6、5×10-7、10-7mol/L吡喹酮溶液中,0、1、5min后观察比较毛蚴的运动及形态学变化。将各虫株尾蚴分别暴露于10-5、6×10-7、4×10-7、10-7mol/L吡喹酮溶液中,0、20、40、60、80、100min后,解剖镜下观察尾蚴的泳动、收缩和断尾率的变化。并将结果与曼氏血吸虫株进行比较。结果经10-6,5×10-7、10-7mol/L吡喹酮溶液中24h后,日本血吸虫虫卵的孵化率分别为0.52%、11.90%和49.15%,曼氏血吸虫分别为4.17%、31.37%和92.53%。当暴露于10-6mol/L吡喹酮1min后,日本血吸虫毛蚴的变形率为100.00%,曼氏血吸虫为55.73%;当分别暴露于5×10-7、10-7mol/L吡喹酮5min后,日本血吸虫毛蚴的变形率为96.82%和21.80%,曼氏血吸虫毛蚴为21.80%和0。当暴露于10-5mol/L吡喹酮中40min,日本血吸虫尾蚴的断尾率为96.75%,曼氏血吸虫为28.30%;暴露于4×10-7mol/L吡喹酮中100min,日本血吸虫尾蚴的断尾率为95.82%,曼氏血吸虫为11.40%;当暴露于10-7mol/L吡喹酮中80min,日本血吸虫尾蚴的断尾率为29.65%,曼氏血吸虫尾蚴为0。结论日本血吸虫各现场分离株间在虫卵、毛蚴和尾蚴阶段对吡喹酮的敏感性无明显差异,但均明显高于曼氏血吸虫。研究提示,将毛蚴移入5×10-7mol/L吡喹酮溶液中1min,镜下观察其变形率,可作为日本血吸虫对吡喹酮敏感性的观察指标,可用于现场判断病人化疗失败的原因是否是由于吡喹酮不敏感株产生所引起。将尾蚴移入4×10-7mol/L吡喹酮溶液中80~100min,镜下观察其断尾率,可用于螺体内虫株吡喹酮敏感性监测。梁幼生 戴建荣 李洪军 汪伟 陶永辉 张键锋 李伟 朱荫昌 G.C. Coles M.J. Doenhoff 2007中国血吸虫病防治杂志2007,19,5:12
6Diagnostic techniques for photonic materials based on Raman and Brillouin spectroscopies显示文摘The elastic and vibrational properties of a material,bulk or planar waveguide,are studied by Brillouin and Raman spectroscopy to follow the process of nanocrystals growth in glass-ceramics. The nanoparticles cause the appearance,in the low fre-quency Raman spectrum,of characteristic peaks,whose position depends on the size of the crystals. At the same time,sharp crystal peaks,due to optical phonons,appear in the Raman spectra,allowing the determination of the nucleated phase,and a frequency shift of the Brillouin peaks is observed.M. Mattarelli S.Caponi A. Chiappini M. Montagna E. Moser F. Rossi C.Tosello C. Armellini A. Chiasera M. Ferrari Y. Jestin G. Nunzi Conti S. Pelli G.C. Righini 2007Optoelectronics Letters2007,3,3:11
7CORROSION RESISTANCE OF HOT DIP GALVANIZED STEEL PRETREATED WITH BIS-FUNCTIONAL SILANES MODIFIED WITH NANOALUMINA显示文摘热剧降的腐蚀行为电镀了有二度的钢 pretreated --[ triethoxy-silylpropyl ]与氧化铝粒子修改的 tetrasulfide ( BTESPT )是 passiving 电影的 studied.The 腐蚀电阻被 Tafel 极化曲线和在电镀的钢底层上形成的电气化学的阻抗 spectroscopy.The 电影评估被 Fourier 变换描绘红外线的光谱学并且精力对待的热剧降的散X光检查 spectrometry.The 表面形态学电镀了钢预告的处理与 nanoalumina 粒子根据 silane 电影修改了的结果表演减少了阳极并且 cathodic 水流密度,和在测量频率的增加的全部的阻抗,因而为电镀的钢在在与铬酸盐电影和 silane 相比的 NaCl 答案的沉浸期间拍摄的热剧降改进腐蚀保护。F.J. Shan C.S. Liu S.H. Wang G.C. Qi 2008Acta Metallurgica Sinica(English Letters)2008,21,4:9
8基于GIS和地统计学的土壤养分的空间异质性研究:以红河县迤萨镇为例(英文)显示文摘云南红河哈尼稻作梯田系统是全球重要农业文化遗产保护试点之一。土壤养分是土壤肥力的重要标志,对遗产地土地的可持续利用具有重要作用。运用GIS和地统计学相结合的方法,对红河县迤萨镇的土壤p H、有机质、全氮、碱解氮、有效磷、速效钾的空间变异及分布特征进行了分析。研究结果表明,该区域内的土壤p H、有机质、全氮、碱解氮、速效钾显示出中等变异,其变异系数分别为12.54%、40.14%、40.00%、34.89%、50.48%;有效磷显示出强变异,其变异系数为102.13%;土壤p H、有机质、全氮和速效钾的理论模型为指数模型,有效磷的理论模型为球状模型;土壤全氮、有效磷和速效钾的空间分布状况主要受结构性因子的影响,p H、有机质和碱解氮的空间分布状况受结构性因子和随机因子的共同影响;Kriging插值图较为直观地描述了迤萨镇土壤养分的空间分布状况。通过对土壤各种养分的空间分布状况,对于及时调整施肥等农业管理措施具有一定的指导作用,是进行精准施肥研究的基础工作。李静 闵庆文 李文华 白艳莹 Dhruba Bijaya G.C. 袁正 2014Journal of Resources and Ecology2014,5,4:9
9From monoscale to multiscale modeling of fatigue crack growth:Stress and energy density factor显示文摘The formalism of the earlier fatigue crack growth models is retained to account for multiscaling of the fatigue process that involves the creation of macrocracks from the accumulation of micro damage.The effects of at least two scales,say micro to macro,must be accounted for.The same data can thus be reinterpreted by the invariancy of the transitional stress intensity factors such that the microcracking and macrocracking data would lie on a straight line.The threshold associated with the sigmoid curve disappears.Scale segmentation is shown to be a necessity for addressing multiscale energy dissipative processes such as fatigue and creep.Path independency and energy release rate are monoscale criteria that can lead to unphysical results,violating the first principles.Application of monoscale failure or fracture criteria to nanomaterials is taking toll at the expense of manufacturing super strength and light materials and structural components.This brief view is offered in the spirit of much needed additional research for the reinforcement of materials by creating nanoscale interfaces with sustainable time in service.The step by step consideraton at the different scales may offer a better understanding of the test data and their limitations with reference to space and time.SIH G.C. 2014Science China(Physics,Mechanics & Astronomy)2014,57,1:8
10自然金和银金矿浮选评述显示文摘自然金和银金矿是天然产出的含有金、银和少量铜的合金 ,它们最常见 ,是矿石中的金的主要产出形式。用重选、浮选或氰化法从含 0 1~ 2 0 g/tAu矿石中回收它们已工业化了。本文对有关自然金浮选出版物进行评述。对其它金矿物的回收稍有涉及 ,但是对自然金矿石的基质矿物 (如硫化铁矿物和贱金属硫化物 )也做了一些评论。金和银金矿产在不同类型的矿石中 ,其粒度范围广泛 ,从块金到细粒金 ( 0 1μm) ,甚至细到扫描电镜分辨率以下。浮选应用粒度范围为2 0 0~ 1μm。金和银金矿无捕收剂浮选是一个浮选理论问题 ,这个问题现在还未彻底解决。但是 ,在某些矿石浮选时确实不用捕收剂。了解金与捕收剂 (如黄药或黑药 )作用理论可以指导浮选实践。其作用可能包括黄药在金表面上吸附和黄药离子与氧发生电化学反应。在金浮选实践中影响其浮选的因素包括金粒的物理条件 (粒度、形状、局部组成变化、表面复盖膜 )、矿石的矿物组成 (黄铁矿、毒砂、贱金属硫化矿物和石英 )、干扰的矿物 (叶腊石、炭 )和非矿石物质 (水泥充填物、矿山木材和磨损的铁屑 )。浮选化学条件包括捕收剂 (黄药、黑药、巯基苯并噻唑、胺 )、起泡剂 (MIBC、Aerofroth)、活化剂 (硫酸铜 )、抑制剂 (石灰、氰化物、亚硫酸盐、硫化物、古尔胶 )。G.C.阿兰 崔洪山 李长根 2002国外金属矿选矿2002,39,1:8
11急性失代偿性心力衰竭院内死亡率的危险分层:分类回归树分析Fonarow G.C. Adams Jr. K.F. Abraham W.T. 张迎捷 2005世界核心医学期刊文摘(心脏病学分册)2005,0,6:8
12RESEARCH ON THE FORMATION MECHANISM OF INTERNAL CRACK IN THE CONTINUOUS CASTING SLAB显示文摘In view of the periodic bending deformation of solid-liquid interface in the solidification process for continuous casting slab, the variation of temperature gradient and dendritic spacing in the front edge of the solid-liquid interface, and the nucleation and propagation process of crack were studied. It is shown that the bending deformation of the interface results in the temperature field change in the front edge of solid-liquid interface, and the occurrence of temperature gradient along drawing direction results in the growth of secondary dendrites. The initial crack formed during the middle and final stage of solidification may extend to the surface of the casting slab and become an internal crack. The results of the theoretical analysis are basically in agreement with that of the experiment.G.W. Chang G.C. Jin S.Y. Chen X.D. Yue 2007Acta Metallurgica Sinica(English Letters)2007,20,1:6
13壁垒型铝阳极氧化膜的成分及电解质离子在膜中的漂移显示文摘徐源 Thompson G.E. Wood G.C. Bethune B.B 1987中国腐蚀与防护学报1987,7,3:5
14MICROSTRUCTURE FORMATION AND MECHANICAL PROPERTY INVOLVING ICOSAHEDRAL QUASICRYSTAL PHASE OF Y RICH Mg-Zn-Y QUASICRYSTAL ALLOY显示文摘The microstructure formation and mechanical property involving icosahedral quasicrystal (I-phase) in the Y-rich Mg-Zn-Y alloy have been studied. The equilibrium formation of I-phase from the Y-rich Mg-Zn-Y melt is through a peritectic reaction between the Y-rich melt and the primary W-phase, which is discussed in detail. The independent nucleation and coupling growth mechanism between the W-phase and the I-phase, from the melt, are revealed, which is significant for understanding the peritectic reaction process involving icosahedral quasicrystal in the Mg-Zn-Y alloy. The mechanism of the quasicrystal phase strengthened magnesium alloys is also discussed here.D.Q. Wan G.C. Yang M. Zhu 2007Acta Metallurgica Sinica(English Letters)2007,20,6:4
15动脉血管流动计算的伽辽金有限元法研究显示文摘得到大动脉三维模型的过二重分叉的二维截定常流的NS方程有限元解· 采用了物理坐标系变换到曲线边界贴体坐标系的数学技巧· 以支流至主动脉流率为参数 ,计算了雷诺数为 10 0 0的壁面切应力· 所得结果与前人的工作 (包括实验数据 )进行了比较 ,发现与他们的结果非常接近 ,改进了Sharma和Kapoor(1995 )的工作 ,相比之下 ,所用的数值方法上更经济 ,适用的雷诺数更大·G.C.夏玛 马德胡.珍 阿尼尔.克乌玛 2001应用数学和力学2001,22,9:4
16热辐射对粘性流体流过多孔非线性收缩平面时的MHD流动和热传导的影响显示文摘研究热辐射对多孔非线性收缩平面上磁流体动力学(MHD)流动和热传导的影响.假设收缩平面的速度和横向磁场,按离原点距离的幂函数而变化;又假设粘性按与其有关的温度的反函数变化,热传导率按温度的线性函数变化.通过广义相似变换,将偏微分方程的控制方程,简化为耦合的非线性常微分方程,然后通过有限差分法进行数值求解.在不同的参数取值下,得到速度和温度分布,以及多孔平面上表面摩擦因数和热传导率的数值结果.G.C.斯特 R.哈尔达 海治 2011应用数学和力学2011,32,6:4
17THE ELECTROMAGNETIC FIELD CALCULATION AND ANALYSIS OF LEVITATION MELTING WITH COLD CRUCIBLE显示文摘In this paper, using the quasi-3D coupled current method, the influences of structure of cold crucible, the power frequency, the electricity property of melt, the coil position and current on the electromagnetic field (EMF) and the levitation characteristics in the melting processes are analyzed. It is shown that in the processes of levitation melting with cold crucible, the power frequency and cold crucible structure are the decisive factors for the ability of magnetic flux penetrating into cold crucible. The magnetic flux density in cold crucible is reduced as the increasing of power frequency, and this tendency becomes stronger when the power frequency is higher than 100kHz. The segmented structure of cold crucible can reduce the induction eddy in itself effectively, and the higher the power frequency is, the better the result is. So, a cold crucible can be segmented into 16-20 sectors for high frequency electromagnetic field and/or 8-12 sectors for lower frequency one. It is also shown that the levitation force of melting charge is related to coil current as a parabolic function.K. Deng, Z.M. Ren, J.Q. Chen and G.C. Jiang School of Materials, Shanghai University, Shanghai 200072, China 2000Acta Metallurgica Sinica(English Letters)2000,13,2:3
18PEK-C/PEEK共混物的研究显示文摘用挤出方法制备了新型聚芳醚酮(PEK-C)和聚醚醚酮(PEEK)共混物。对共混体系的相容性、转变、结晶结构及力学性能等进行了研究。初步结果显示了PEK-C和PEEK具有很好的互补和协同作用,表明该共混物是一种很有前途的工程材料。李滨耀 李刚 张延 何天白 陈天禄 ALFONSO G.C. 1991高分子材料科学与工程1991,7,2:3
19Spreading behavior and microstructure characteristics of dissimilar metals TIG welding–brazing of aluminum alloy to stainless steel显示文摘J.L. Song S.B. Lin C.L. Yang G.C. Ma H. Liu 2009Materials Science & Engineering A2009,,1:3
20考虑到渗透效应的一种血液流动的计算方法显示文摘 得到了定常情况下,狗二分叉动脉横截面的三维Navier_Stokes方程的有限元处理方法,并考虑到管壁的渗透影响,数值方法还包括直角坐标和曲线坐标的变换· 详细讨论了渗透性影响下的定常流、分叉流以及切应力情况· 以分支和主干血管的速度比为参量,计算雷诺数为1000情况下管壁切应力,数值结果和先前的实验结果符合得很好· 该文的工作是Sharma等(2001)工作的改进,使计算量更小。A.克乌玛 C.L.范西尼 G.C.夏玛 滕忠照 2005应用数学和力学2005,26,1:3
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