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Membrane Transporters for Nitrogen,Phosphate and Potassium Uptake in Plants

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Journal of Integrative Plant Biology 2008年第7期50卷 835-848页

作者： Yi-Fang Chen Yi wang wei-hua Wu State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University National Plant Gene Research Centre Beijing 100094 China

Nitrogen, phosphorous and potassium are essential nutrients for plant growth and development. However, their contents in soils are limited so that crop production needs to invest a lot for fertilizer supply. To explore the genetic potentialities of crops （or plants） for their nutrient utilization efficiency has been an important research task for many years, in fact, a number of evidences have revealed that plants, during their evolution, have developed many morphological, physiological, biochemical and molecular adaptation mechanisms for acquiring nitrate, phosphate and potassium under stress conditions. Recent discoveries of many transporters and channels for nitrate, phosphate and potassium uptake have opened up opportunities to study the molecular regulatory mechanisms for acquisition of these nutrients. This review aims to briefly discuss the genes and gene families for these transporters and channels, in addition, the functions and regulation of some important transporters and channels are particularly emphasized.

关键词： Arabidopsis channel nitrate potassium phosphate transporter.

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

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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

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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

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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

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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

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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

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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

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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

Characteristics and Possible Formation Mechanisms of Severe Storms in the Outer Rainbands of Typhoon Mujigae(1522)

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Journal of Meteorological Research 2017年第3期31卷 612-624页

作者： Bingyun wang Ming wei wei hua Yongli ZHANG Xiaohang WEN Jiafeng ZHENG Nan LI Han LI Yu WU Jie ZHU Mingjun ZHANG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology College of Atmospheric Sciences Chengdu University of Information Technology/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province Hainan Meteorological Observatory National Satellite Meteorological Center

To better understand how severe storms form and evolve in the outer rainbands of typhoons, in this study, we in- vestigate the evolutionary characteristics and possible formation mechanisms for severe storms in the rainbands of Typhoon Mujigae, which occurred during 2-5 October 2015, based on the NCEP-NCAR reanalysis data, conventional observations, and Doppler radar data. For the rainbands far from the inner core （eye and eyewall） of Mujigae （dis- tance of approximately 70-800 kin）, wind speed first increased with the radius expanding from the inner core, and then decreased as the radius continued to expand. The Rankine Vortex Model was used to explore such variations in wind speed. The areas of strong stormy rainbands were mainly located in the northeast quadrant of Mujigae, and overlapped with the areas of high winds within approximately 300-550 km away from the inner core, where the strong winds were conducive to the development of strong storms. A severe convective cell in the rainbands de- veloped into waterspout at approximately 500 km to the northeast of the inner core, when Mujigae was strengthening before it made landfall. Two severe convective cells in the rainbands developed into two tornadoes at approximately 350 km to the northeast of the inner core after Mujigae made landfall. The radar echo bands enhanced to 60 dBZ when mesocyclones occurred in the rainbands and induced tornadoes. The radar echoes gradually weakened after the mesocyclones weakened. The tops of parent clouds of the mesocyclones elevated at first, and then suddenly dropped about 20 min before the tornadoes appeared. Thereby, the cloud top variation has the potential to be used as an early warning of tornado occurrence.

关键词： strong typhoon rainband severe storm tomado Rankine Vortex Model