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Chinese Physics Letters 2016年第7期33卷 110-112页

作者：吴忠振肖舒崔岁寒傅劲裕田修波朱剑豪潘锋 School of Advanced Materials Peking University Shenzhen Graduate School Department of Physics and Materials Science City University of Hong Kong State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

A non-sputtering discharge is utilized to verify the effect of replacement of gas ions by metallic ions and consequent decrease in the secondary electron emission coefficient in the discharge current curves in high-power impulse magnetron sputtering （HiPIMS）. In the non-sputtering discharge involving hydrogen, replacement of ions is avoided while the rarefaction still contributes. The initial peak and ensuing decay disappear and all the discharge current curves show a similar feature as the HiPIMS discharge of materials with low sputtering yields such as carbon. The results demonstrate the key effect of ion replacement during sputtering.

关键词： of in Origin of Initial Current Peak in High Power Impulse Magnetron Sputtering and Verification by Non-Sputtering Discharge is by

Alleviation by abscisic acid of Al toxicity in rice bean is not associated with citrate efflux but depends on ABI5-mediated signal transduction pathways

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Journal of Integrative Plant Biology 2019年第2期61卷 140-154页

作者： Wei Fan Jia Meng Xu Pei Wu Zhi Xin Yang He Qiang Lou Wei Wei Chen Jian Fen Jin Shao Jian Zheng Jian Li Yang College of Resources and Environment Yunan Agricultural University State Key Laboratory of Plant Physiology and Biochemistry College of Life Sciences Zhejiang University Institute of Life Sciences College of Life and Environmental Sciences Hangzhou Normal University

Under conditions of aluminum(Al) toxicity,which severely inhibits root growth in acidic soils, plants rapidly alter their gene expression to optimize physiological fitness for survival. Abscisic acid(ABA) has been suggested as a mediator between Al stress and gene expression, but the underlying mechanisms remain largely unknown. Here,we investigated ABA-mediated Al-stress responses, using integrated physiological and molecular biology *** demonstrate that Al stress caused ABA accumulation in the root apex of rice bean(Vigna umbellata [Thunb.] Ohwi &Ohashi), which positively regulated Al tolerance. However,this was not associated with known Al-tolerance mechanisms. Transcriptomic analysis revealed that nearly one-third of the responsive genes were shared between the Al-stress and ABA treatments. We further identified a transcription factor, ABI5, as being positively involved in Al tolerance. Arabidopsis abi5 mutants displayed increased sensitivity to Al, which was not related to the regulation of AtALMT1 and AtMATE expression. Functional categorization of ABI5-mediated genes revealed the importance of cell wall modification and osmoregulation in Al tolerance, a finding supported by osmotic stress treatment on Al tolerance. Our results suggest that ABA signal transduction pathways provide an additional layer of regulatory control over Al tolerance in plants.

关键词： Alleviation by abscisic acid of Al toxicity in rice bean is not associated with citrate efflux but depends on ABI5-mediated sign ABA Figure ABI

Quasinormal Modes of the Schwarzschild Black Hole Surrounded by the Quintessence Field in Rastall Gravity

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Communications in Theoretical Physics 2018年第12期69卷 695-704页

作者： Jun Liang School of Arts and Sciences Shannxi University of Science and Technology

The quasinormal modes of the Schwarzschild black hole surrounded by the quintessence in Rastall gravity are studied using the sixth-order Wentzel-Kramers-Brillouin approximative approach. The effect of the Rastall parameter on the quasinormal modes of gravitational, electromagnetic and massless scalar perturbations is explored. Compared to the case of Einstein gravity, it is found that, when η 0, the gravitational field, electromagnetic field as well as massless scalar field damp more slowly and have smaller real frequency of oscillation in Rastall gravity. It is also found that the gravitational field, electromagnetic field as well as massless scalar field damp more and more slowly and the real frequency of oscillation for the gravitational perturbation, electromagnetic perturbation as well as massless scalar perturbation becomes smaller and smaller as the Rastall parameter η *** among the quasinormal frequencies of gravitational, electromagnetic and massless scalar perturbations, I find that, for fixed η,(l, n), ε and Nq, the oscillation damps most slowly for the gravitational perturbation, mediate for the electromagnetic perturbation and most rapidly for the massless scalar perturbation, and the real frequency of oscillation is the smallest for the gravitational perturbation, mediate for the electromagnetic perturbation and the largest for the massless scalar perturbation in Rastall gravity.

关键词： quasinormal modes Rastall gravity Schwarzschild black hole surrounded by the quintessencefield WKB approximation

AEROBIC　EPOXIDATION　OF　STYRENE　CATALYZED　by　MAGNESIUM　OXIDE　SUPPORTED　POLYTITAZANE　COBEST（III）　COMPLEXES

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Chinese Chemical Letters 1996年第8期7卷 749-752页

作者： Yuan Yong YAN Tie Jun WANG Jian Ping GUO Mei Yu HUANG Ying Yan JLANG(InstitUte of Chemistry, Academia Sinica, Beijing 100080) Institute of Chemistiy Academia Sinica Beijing 100080

Magnesium oxide supported polghtazane-cobalt (III) complex has been prepared and foundto be capable of catalyzing the epoxidaton of styrene to form styrene oxide in 88.0 % yield in thepresence of isobutyraldehyde under an atmospheric pressure of molecular oxygen at roomtemperafor. XPS data shows that the high valent cobalt (III) is stabilized by the multidentate nitrogenligand of polytitazane. Dichloroethane is the best solvent chosen for this reaction. The catalyst can bereused for several times without any remarkable loss in catalytic activity and selectivity.

关键词： III COBEST by AEROBIC

Interaction of Pair Particles Mediated by Signal Molecules

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Chinese Physics Letters 2016年第1期33卷 140-143页

作者：陈江星郑强黄春云徐江荣应和平 Department of Physics Hangzhou Dianzi University Department of Physics Nanjing University Department of Physics Zhejiang University

A mesoscopic model is set up to study the predatorprey-like phenomenon between two chemically active objects. A target sphere （T） secretes chemical signal molecules that are detected and traced by a hunter sphere （H）. The distribution of signal molecules diffusing around the target is simulated and analyzed. The chemotactic behavior of the hunter along the gradient of signal molecules results in the capture of the target. The dependences of capture time tc on different conditions are focused on. It is found that the values of capture time rely on their initial separation d as a power law tc ∝ d^a. The exponent a depends on decay rate of signal molecules. The capture time increases with the decay rate. The increases of target and hunter size both lead to the decrease of the capture time, which is also shown by the power law behavior. The detailed chemotaxis process is investigated.

关键词： of on is or as by in

Size estimates of nobel gas clusters by Rayleigh scattering experiments

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Chinese Optics Letters 2003年第11期1卷 653-655页

作者：朱频频倪国权徐至展 Laboratory for High Intensity Optics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800

Noble gases (argon, krypton, and xenon) are puffed into vacuum through a nozzle to produce clusters for studying laser-cluster interactions. Good estimates of the average size of the argon, krypton and xenon clusters are made by carrying out a series of Rayleigh scattering experiments. In the experiments, we have found that the scattered signal intensity varied greatly with the opening area of the pulsed valve. A new method is put forward to choose the appropriate scattered signal and measure the size of Kr cluster.

关键词： of as on that Size estimates of nobel gas clusters by Rayleigh scattering experiments is have into been by for

A new compensation method for temperature-dependent gain tilt in L-band EDFA by adjusting only inserted VOA

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Chinese Optics Letters 2003年第8期1卷 451-454页

作者：蒋俏峰刘小明王青王燕 Department of Electronic Engineering Tsinghua University Beijing 100084

A novel compensation method for temperature-dependent gain tilt of L-band erbium-doped fiber amplifier (L-EDFA) is proposed, in which the attenuation between stages is the only parameter to be adjusted. A simple linear relationship between the attenuation and the erbium fiber coil temperature was derived theoretically. When the erbium fiber coil temperature cycles from 26 to 70C, the gain tilt variation less than 0.3 dB is achieved experimentally by adjusting only the pre-inserted variable optical attenuator (VOA).

关键词： EDFA de A new compensation method for temperature-dependent gain tilt in L-band EDFA by adjusting only inserted VOA by for in

CH_3NH_3 Formed by Electron Injection at Heterojunction Inducing Peculiar Properties of CH_3NH_3PbI_3 Material

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Chinese Physics Letters 2019年第2期36卷 36-39页

作者： Ao Zhang Yun-Lin Chen Chun-Xiu Zhang Jun Yan Department of Physics School of Science Beijing Jiaotong University Beijing Institute of Graphic Communication

The effect of formed CH_3NH_3 at the heterojunction on properties of CH_3NH_3PbI_3 material is investigated based on experiment and theoretical calculation. Our calculation results show that the giant dielectric constant, anomalous hysteresis and long-lasting polarization for CH_3NH_3PbI_3 originate from the formed CH_3NH_3 at the heterojunction. It is found that the induced weak EPS by the reorientation of CH_3NH_3 sub-group along the built-in electric field enables us to effectively increase the ordering of entire lead-halide framework. In addition, the heterojunction has an advantage of channel separation between carrier transport and electron diffusion. These properties of the heterojunction are the main origin of the high efficiency of CH_3NH_3PbI_3 solar cells.

关键词： CH3NH3 Formed by Electron Injection Inducing Peculiar Properties of CH3NH3PbI3 Material

Superhard BC_2N:an Orthogonal Crystal Obtained by Transversely Compressing(3,0)-CNTs and(3,0)-BNNTs

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Chinese Physics Letters 2016年第10期33卷 94-98页

作者：胡玉洁徐胜亮王昊刘恒徐雪春蔡影祥 Department of Physics Nanchang University

by means of density functional theory calculations, an orthogonal boron-carbon-nitrogen compound called （3,0）- BC2N is predicted, which can be obtained by transversely compressing （3,03 carbon nanotubes （CNTs） and boron nitride nanotubes （BNNTs）. Its structural stability, elastic properties, mechanical properties and electronic structure are systematically investigated. The results show that （3,0）-BU2N is a superhard material with a direct bandgap. However, its similar structures, （3,0）-C and （3,0）-BN are indirect semiconductors. Strikingly, （3,0）-C is harder than diamond. We also simulate the x-ray diffraction of （3,0）-BC2N to support future experimental investigations. In addition, our study shows that the transition from （3,03 CNTS and BNNTs to （3,0）-BC2N is irreversible.

关键词： CNTs and is of BC BNNTs Superhard BC2N:an Orthogonal Crystal Obtained by Transversely Compressing by

White Light Emission from ZnS:Mn Thin Films Deposited on GaN Substrates by Pulsed Laser Deposition

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Chinese Physics Letters 2016年第7期33卷 129-132页

作者：王彩凤李清山王继锁赵风周张立春 College of Physics and Engineering Qufu Normal University College of Aeronautical Engineering Binzhou University School of Physics and Optoelectronic Engineering Ludong University

ZnS：Mn thin films are grown on CaN substrates by pulsed laser deposition. The structure, morphology and optical properties are investigated by x-ray diffraction, scanning electron microscopy and photolumineseenee （PL）. The obtained ZnS：Mn thin films are grown in preferred orientation along β-ZnS （111） direction corresponding to crystalline structure of cubic phase. The deposition temperature has an obvious effect on the structure, surface morphology and optical properties of ZnS：Mn thin films. PL measurements show that there are two emission bands located at 44Ohm and 595 nm when the films are deposited at temperatures from 100℃ to 500℃. The relative integrated intensity of the blue emission and orange-red emission is determined by the deposition conditions. At the proper deposition temperature of 300℃, the color coordinate is closest to （0.33, 0.33）. The ZnS：Mn films on CaN substrates can exhibit white light emission.

关键词： ZnS in rate GaN Mn by from