检索结果-南通市图书馆

Mie Potential and Equation of State of Zr_(48)Nb_(8)Cu_(14)Ni_(12)Be_(18) Bulk Metallic Glass

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2001年第6期18卷 805-807页

作者： ZHANG Yong PAN Ming-Xiang wang wei-hua Institute of Physics and Center for Condensed Matter Physics Chinese Academy of SciencesBeijing 100080 National Microgravity Laboratory of Chinese Academy of Sciences Beijing 100080

The linear expansion of Zr_(48)Nb_(8)Cu_(14)Ni_(12)Be_(18) bulk metallic glass(BMG)with excellent glass forming ability and high thermal stability is investigated by a dilatometry *** average expansion coefficient is α TG=1.04 × 10^(-5) K^(-1)(300-656 K)for the BMG and α TG=1.11 × 10^(-5) K^(-1)(356~890 K)for the crystallized *** Mie potential as well as the equation of state of the BMG and its corresponding crystallized state are determined from the thermal expansion and ultrasonic data,and the differences among them are phenomenologically explained.

关键词： alloy. expansion thermal

Atmospheric heterogeneous reaction of acetone:Adsorption and desorption kinetics and mechanisms on SiO_2 particles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2008年第7期53卷 1004-1010页

作者： JIE ChongYu CHEN ZhongMing wang HongLi hua wei wang CaiXia LI Shuang The State Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China

Acetone plays an important role in photooxidation processes in the atmosphere. Up to date, little is known regarding the heterogeneous fate of acetone. In this study, the adsorption and desorption processes of acetone on SiO2 particles, which are the major constituent of mineral dust in the atmos-phere, have been investigated for the first time under the simulated atmospheric conditions, using in situ transmission Fourier transform infrared spectroscopy. It is found that acetone molecules are ad-sorbed on the surfaces of SiO2 particles by van der Waals forces and hydrogen bonding forces in a nonreactive and reversible state. The rates of initial adsorption and initial desorption, initial uptake coefficients and adsorption concentrations at equilibrium have been determined at different relative humidity. The presence of water vapor cannot result in the formation of new substances, but can de-crease the adsorption ability by consuming or overlapping the isolated OH groups on the surfaces of SiO2 particles. In the desorption process, a considerable amount of acetone molecules will remain on SiO2 particles in dry air, whereas acetone molecules are almost completely desorbed at a high relative humidity. In order to evaluate the role of heterogeneous reactions of acetone and other carbonyl compounds in the atmosphere, a new model fitting the atmospheric conditions is needed.

关键词：丙酮大气反射吸附作用脱附作用二氧化硅

A New Calibration Method for an Inertial and Visual Sensing System

在线全文

学校读者我要写书评

暂无评论

International Journal of Automation and computing 2012年第3期9卷 299-305页

作者： Xu, De wang, hua-wei Li, You-Fu Tan, Min State Key Laboratory of Intelligent Control and Management of Complex Systems Institute of Automation Chinese Academy of Sciences Beijing 100190 China East China Research Institute of Electronic Engineering Hefei 230088 China Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Hong Kong China

The relative pose between inertial and visual sensors equipped in autonomous robots is calibrated in two steps. In the first step, the sensing system is moved along a line, the orientations in the relative pose are computed from at least five corresponding points in the two images captured before and after the movement. In the second step, the translation parameters in the relative pose are obtained with at least two corresponding points in the two images captured before and after one step motion. Experiments are conducted to verify the effectiveness of the proposed method.

关键词： Inertial sensor visual sensor calibration motion estimation robot vision.

Third Order Elastic Constants and Anharmonic Properties of the Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10.0)Be_(22.5) Bulk Metallic Glass

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2001年第3期18卷 414-415页

作者： wang Ru-Ju LI Feng-Ying QIN Zhi-Cheng wang wei-hua Institute of Physics Chinese Academy of SciencesBeijing 100080

The longitudinal velocity Vl and shear velocity Vs of ultrasonic wave propagated along arbitrary three perpendicular directions of the Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10.0)Be_(22.5) bulk metallic glass(Zr/Ti BMG)have been measured at ambient pressure,under hydrostatic pressure(up to 0.5 GPa)and uniaxial compression(up to 70 MPa)using the pulse echo overlap *** third order elastic constants and the Grüneisen parameter related to the anharmonic properties were derived and *** was found that the BMG with marked different microstructural characteristics comparing with the amorphous carbon exhibited different behaviours related to shear vibratory under high pressure.

关键词： Elastic harmonic hydrostatic

Synthesis and biological evaluation of a new series of histone deacetylases inhibitors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第6期19卷 673-675页

作者： Jie Jiao Qiang wang hua wei Zhu Hao Fang Wen Fang Xu School of Pharmaceutical Science Shandong University Jinan 250012 China

Histone deacetylases （HDACs） play an important role in tumorigenesis. Inhibition of HDACs is considered as a potent strategy for cancer therapy. Two lead compounds （ja and jb） were found to have activities against HDACs with IC50 at about 15 μmol/L. Then a new series of hydroximic acid derivatives were designed and synthesized based on them. The HDACs activity assay in vitro found that compounds J04 and ,109 are nearly as potent as the positive control drug Zolinza.

关键词： HDACs Tumorigenesis Cancer therapy Hydroximic acid

Effects of Hydroxyapatite Nanoparticles on Apoptosis and Invasion of Human Renal Cell Carcinoma 786-0 Cells

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2011年第1期27卷 94-98页

作者： wang Zhi-xin HOU Yi HAN wei wang Kai-chen GUO Bao-feng LIU Ying CHANG Xi-hua wang wei-hua NA Wan-li KONG Xiang-bo ZHAO Xu ZHANG Ling Department of Urology China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China College of Chemistry Department of Pathophysiology Norman Bethune Medical School Jilin University Changchun 130021 P. R. China

Renal cell carcinoma is the most common cancer of the kidney, and resistant to traditional therapies. The aim of this study is to investigate the effects of hydroxyapatite nanoparticles on human renal cell carcinoma 786-0 cells. Cell proliferation was assessed with an 3-（4,5-dimethylthiazol-2-yl） 2,5-diphenyltetrazolium bromide（MTT） staining kit. The apoptosis assay was assessed with an FITC Annexin V Apoptosis Detection Kit. Caspase-3 and caspase-12 were detected by immunocytochemical staining and semi-quantitative RT-PCR. Cell wound healing assay was used to ensure cell motility. Matrigel invasion assay was analysed via transwell chambers. Our results showed that hydroxyapatite nanoparticles significantly reduced cell proliferation, invasion and induced apoptosis of 786-0 cells. The inhibiting action may have relation with up-regulated caspase-12, leading the cells to apoptosis. This study suggests that hydroxyapatite nanoparticles may be an effective and delivery system for renal cell carcinoma therapy.

关键词： Renal cell carcinoma Hydroxyapatite nanoparticle Apoptosis Invasion

Specific Heat in a Typical Metallic Glass Former

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2012年第4期29卷 157-160页

作者： KE Hai-Bo ZHAO Zuo-Feng WEN Ping wang wei-hua Institute of Physics Chinese Academy of SciencesBeijing 100190

The specific heat in a typical Pd_(40)Ni_(10)Cu_(30)P_(20) metallic glass forming system is *** is found that the specific heat of the metallic liquid is around 4.7R (R is the gas constant) and that it is almost independent of *** glass transition observed during cooling is accompanied by a decrease in the specific heat of *** specific heat of the metallic glass is similar to that of its crystalline phases,contributed mainly from atomic *** with the results of the structural relaxation and diffusivities,we demonstrate an intrinsic connection between the atomic motion and the specific heat in the metallic glass-forming *** results support the idea that glass transition is a process accompanied by the freezing of most of the atomic transitional motions in a metallic supercooled liquid during cooling.

关键词： temperature metallic glass

Plant Sensing and Signaling in Response to K＋-Deficiency

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2010年第2期3卷 280-287页

作者： Yi wang wei-hua Wu State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) National Plant Gene Research Centre (Beijing) College of Biological Sciences ChinaAgricultural University Beijing 100193 China

Potassium （K＋） is one of the essential macronutrients for plant growth and development. However, K＋ content in soils is usually limited so that the crop yields are restricted. Plants may adapt to K＋-deficient environment by adjusting their physiological and morphological status, indicating that plants may have evolved their sensing and signaling mechanisms in response to K＋-deficiency. This short review particularly discusses some components as possible sensors or signal transducers involved in plant sensing and signaling in response to K＋-deficiency, such as K＋ channels and transporters, H＋-ATPase, some cytoplasmic enzymes, etc. Possible involvement of Ca2＋ and ROS signals in plant responses to K＋-deficiency is also discussed.

关键词： K+-deficiency K+ channel K+ transporter Ca2+ signaling.

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

二维有限元方法研究石墨烯环中磁等离激元

物理学报 2023年第8期72卷 287-295页

作者：王伟华中国矿业大学材料与物理学院徐州221116

石墨烯等离激元是决定石墨烯光学性质的重要元激发,拥有一系列优异的特性,其通过外置电场的动态可调性最引人注目;石墨烯具有很强的磁场响应(如室温观测的量子霍尔效应),因而磁场可作为一个新的调控自由度,形成的准粒子叫作石墨烯磁等... 详细信息

石墨烯等离激元是决定石墨烯光学性质的重要元激发,拥有一系列优异的特性,其通过外置电场的动态可调性最引人注目;石墨烯具有很强的磁场响应(如室温观测的量子霍尔效应),因而磁场可作为一个新的调控自由度,形成的准粒子叫作石墨烯磁等离激元.鉴于石墨烯的二维属性,石墨烯磁等离激元的研究大多采用三维近似,即将石墨烯等效成厚度很薄的三维块材,该处理方案需消耗大量的计算资源.本文在准静态近似下,围绕库仑定律和电荷守恒定律,构建了高效的二维有限元方法,自洽地求解石墨烯面内的积分微分方程,并提出本征值损失谱表征准粒子的激发.利用二维有限元方法,探讨了4类石墨烯环中磁等离激元的激发;最低阶的偶极共振都支持磁等离激元的对称劈裂,在孔很小时,其对模式劈裂的影响可忽略,但当孔的尺寸变大时,内外边界的相互作用将抑制模式劈裂,并最终导致其消失.

关键词：石墨烯磁等离激元有限元方法本征值损失谱

维普期刊数据库博看期刊