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chinese Physics Letters 1996年第4期13卷 269-272页

作者： ZOU Yu TONG Xiao-min LI Jia-ming Institute of Physics Chinese Academy of SciencesBeijing 100080 Institute of Applied Physics and Computational Mathematics Beijing 100088

The compact physical parameters(μ_(α),U_(iα))in multichannel quantum defect theory(MQDT)can be directly calculated with relativistic multichannel theory(RMCT).Here we report a systematic study of the MQDT parameters(fiay Uia)with RMCT along the Ne-like iso-electronic sequence(including Ca^(10+),Fe^(16+),Ge^(22+),Ag^(37+) ions).We find that the physical parameters(μ_(α),U_(iα))show a very interesting scaling behavior along the iso-electronic sequence.

关键词： electronic MQDT scaling

STRUCTURAL INVESTIGATION OF A NEW POLYORGANOSILOXANE CONTAINING NANOTUBULAR CAVITIES USING ORGANIC FLUORESCENT PROBES

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chinese Journal of Polymer science 1999年第4期17卷 383-389页

作者：张榕本 Polymer Chemistry Laboratory of chinese Academy of sciences and China Petro-Chemical Corporation Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Fluorescent molecules - p-dimethylaminobenzonitrile (DMABN) and trans-stilbene (TSB ) - were used as probes to investigate the inner structure of the nanotubular cavities contained in a new polyorganosiloxane (POS) which was prepared by the hydrosilylation coupling reaction of cis-isotactic ladderlike polyvinylsilsesquioxane (Vi-T) with 1,1,3,3-tetramethyldisiloxane (H-MM) as coupling agent in the presence of catalyst dicyclopentadienyldichloroplatinum (Cp2PtCl2). The results from FTIR spectra and fluorescence spectra in combination with molecular simulation reveal that the cross-section of the nanotubular cavity is nearly rectangular in shape, and is about 0.62 nm in width and about 0.38 nm in height. This work gains in-depth knowledge into the inner structure of the nanotubular cavities of POS and furthermore provides a guide to the selection of proper guest molecules in constructing functional supramolecular clathrate based upon POS.

关键词： polyorganosiloxane nanotubular cavities fluorescent probes

Ideal type 1 is caused by a point mutation in the a-tubulin gene that affects microtubule arrangement in soybean

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The Crop Journal 2023年第3期11卷 713-722页

作者： Bohong Su Yong Guo Zhongfeng Li Huawei Gao Zhongyan Wei Lijuan Qiu College of Agriculture Northeast Agricultural UniversityHarbin 150030HeilongjiangChina National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China College of Agronomy Henan Agricultural UniversityZhengzhou 450002HenanChina State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Key Laboratory of Biotechnology in Plant Protection of MARA of China and Zhejiang ProvinceInstitute of Plant VirologyNingbo UniversityNingbo 315211ZhejiangChina

Plant architecture is a target of crop *** soybean mutant ideal type 1(it1)displays a pleiotropic phenotype characterized by compact plant architecture,reduced plant height,shortened petioles,wrinkled leaves,and indented *** analysis revealed that the pleiotropic phenotype was controlled by an incomplete dominant *** characterized the cellular phenotypes of it1 and positionally cloned the it1 *** morphogenetic analysis of the it1 mutant revealed an excess of xylem cells and expanded phloem,and polygonal pavement *** cloning showed that the phenotype was caused by a G-to-A mutation in the second exon of the a-tubulin gene(Glyma.05G157300).The mutation altered microtubule arrangement in pavement cells,changing their *** of Gmit1 resulted in an it1-like phenotype and polygonal pavement cells and microtubules of overexpressors were parallel or slightly *** suppressor mutants able to suppress the phenotype of it1 were obtained by EMS mutagenesis in the it1 *** these mutants carried an additional mutation in the it1 *** results suggest that the pleiotropic phenotype of it1 is caused by the mutation in the atubulin gene.

关键词： Soybean Plant architecture a-Tubulin Microtubules Intragenic mutations

Identification and validation of stable quantitative trait loci for yield component traits in wheat

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The Crop Journal 2023年第2期11卷 558-563页

作者： Lingli Li Yingjie Bian Yan Dong Jie Song Dan Liu Jianqi Zeng Fengju Wang Yong Zhang Zhonghu He Xianchun Xia Yan Zhang Shuanghe Cao Institute of Crop sciences National Wheat Improvement CenterChinese Academy of Agricultural SciencesBeijing 100081China International Maize and Wheat Improvement Center(CIMMYT)China Office Beijing 100081China

Grain weight and grain number are important yield component traits in wheat and identification of underlying genetic loci is helpful for improving ***,we identified eight stable quantitative trait loci(QTL)for yield component traits,including five loci for thousand grain weight(TGW)and three for grain number per spike(GNS)in a recombinant inbred line population derived from cross Yangxiaomai/Zhongyou 9507 across four *** grain size is a major determinant of grain weight,we also mapped QTL for grain length(GL)and grain width(GW).***-2D,***-3B,***-5A and ***-7A.2 for TGW co-located with those for grain ***-2D also had a consistent genetic position with ***-2D,suggesting that the pleiotropic locus is a modulator of trade-off effect between TGW and *** and linkage mapping showed that TaGL3-5A and WAPO-A1 were candidate genes of ***-5A and ***-7A.2,*** developed Kompetitive allele specific PCR(KASP)markers linked with the stable QTL for yield component traits and validated their genetic effects in a diverse panel of wheat cultivars from the Huang-Huai River Valley ***-based genotyping analysis further revealed that the superior alleles of all stable QTL for TGW but not GNS were subject to positive selection,indicating that yield improvement in the region largely depends on increased *** analyses with previous studies showed that most of the QTL could be detected in different genetic backgrounds,and ***-7A.1 is likely a new *** findings provide not only valuable genetic information for yield improvement but also useful tools for marker-assisted selection.

关键词： Grain number per spike KASP marker QTL mapping Thousand grain weight Triticum aestivum

Evaluating the Impact of Optical Axis Stability on Exoplanet Detection

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Research in Astronomy and Astrophysics 2022年第2期22卷 86-91页

作者： Dong-Jie Tan Jia-Cheng Liu Zi Zhu Niu Liu School of Astronomy and Space science Key Laboratory of Modern Astronomy and Astrophysics(Ministry of Education)Nanjing University163 Xianlin Avenue210023 NanjingChina

For detecting exoplanets with high precision,using the angular distance between the two stars to detect the periodic motion of the star will be a better *** approach can avoid importing the position error of the reference catalog in the process that uses a traditional photographic plate to derive the star position *** the precision level of microarcseconds,the error caused by optical axis deviation is not *** this paper,we evaluate the impact of the stability of the optical axis on the relative angular distance measurement from the aspects of theoretical analysis and numerical *** the angular distance error limit of 1 microarcsecond is given,the upper limit of optical axis deviation is estimated to be 68 *** addition,when limiting the deviation of the optical axis,we give the corresponding error allowance of angular distance ***,we also discuss the way to resolve the problem of CCD distortion and focal length change on the measurement of angular *** work in this paper is of guiding significance to the design of a telescope.

关键词： instrumentation:high angular resolution methods:numerical planets and satellites:detection

SYNTHESIS AND PROPERTIES OF ANILING ANILING AND 0-AMINOBENZENESULFONIC ACID COPOLYMER

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chinese Journal of Polymer science 1999年第2期17卷 165-170页

作者： Jun-hua Fan Mei-xiang Wan Dao-ben Zhu Institute of Chemistry, chinese Academy of sciences, Beijing 100080, China Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Poly(aniline- co-o-aminobenzenesulfonic acid) (PAOABSA) as a water soluble conducting polymerwas synthesized by chemical polymerization. The productivity and the room-temperature conductivity of thecopolymer were measured as a function of the reaction conditions, such as reaction temperature, the ratio ofoxidant to monomer and the degree of sulfonation defined as the ratio of sulfur to nitrogen atoms(S/N). Themain results obtained are summarized as follows : (1) lower reaction temperature (at about 0℃) is favorablefor the enhancement of the room-temperature conductivity of the copolymer; (2) higher content of oxidant isunfavorable for increasing the room-temperature conductivity of the copolymer; (3) both productivity androom-temperature conductivity of the copolymer decrease with increase of the degree of sulfonation whichwas always lower than 0.5 even an excess of o-aminobenzenesulfonic acid was added, probably because thereactivity ratio of aniline (γ=2.99± 0.05) is much higher than that of o-aminobenzenesulfonic acid (γ_2 = 0.06±0.02) estimated by using Fineman-Ross method and least square method.

关键词： Watersoluble polyaniline Reactivity ratio Copolymer

Effect of the alidade thermal behavior on the pointing accuracy of a large radio telescope

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Research in Astronomy and Astrophysics 2021年第6期21卷 253-262页

作者： Shan-Xiang Wei De-Qing Kong Qi-Ming Wang Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of chinese Academy of sciences Beijing 100049China

The alidade’s non-uniform temperature field of a large radio telescope is very obvious under solar *** a radio telescope’s pointing errors,caused by the alidade deformation under solar radiation,is significant to improve the telescope’s pointing *** study the effect of the alidade thermal behavior on the pointing accuracy of a large radio telescope,a temperature experiment is first carried out in a 70-m radio telescope on a sunny *** to the measured results,the temperature distribution rule of the alidade is summarized *** addition,the alidade’s temperature field is calculated by finite element thermal *** simulated results are proved to be in good agreement with the experimental ***,the alidade deformation under solar radiation is computed by finite element thermalstructure coupling *** telescope’s pointing errors caused by alidade deformation are estimated via the alidade’s node *** final results show that the effect of alidade thermal behavior on the telescope’s elevation pointing errorsΔε2+Δεr is much more than the effect on the telescope’s crosselevation pointing errorsΔε*** maximum ofΔε2+Δεr is more than 45″,while the maximum ofΔε1 is less than 6″.This study can provide valuable references for improving the pointing accuracy of large radio telescopes.

关键词： telescopes finite element analysis thermal behavior pointing accuracy

CO_2 emission from Dianshan Lake in summer,East China

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chinese Journal Of Geochemistry 2013年第4期32卷 430-435页

作者： ZHANG Jing JIANG Yanxing GAO Yang WU Yiying LUO Wenyun ZHOU Zhihua WANG Fushun School of Environmental and Chemical Engineering Shanghai University China Earthquake Networks Center

Shallow fresh water bodies in peat areas could be an important contributor to greenhouse gases in the *** this study,the partial pressure of CO2 in the surface water of the Dianshan Lake was investigated insitu in August *** average pCO2 in the study area was 2300μatm and fluctuated within the range of 989–5000μ***2 showed a reverse trend to the variations of pH and DO in the surface water of the Dianshan *** water to air diffusion flux of CO2 of the upstream,middle lake and downstream were respectively 63,33 and 14mmol/m2/*** average,the diffusion flux of CO2 of the whole lake was 31 mmol/m2/***,our results show that during the sampling season,the Dianshan Lake appears to be a great source of *** is also demonstrated that respiration could be the dominant biochemical reaction in the Dianshan Lake in summer.

关键词： CO2排放量淀山湖中国东部二氧化碳分压夏季扩散通量大气压温室气体

Dynamic Mechanical Behavior and Adiabatic Shear Bands of Ultrafine Grained Pure Zirconium

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Journal of Wuhan University of Technology(Materials science) 2020年第1期35卷 200-207页

作者：刘晓燕 YANG Cheng YANG Xirong LUO Lei HE Xiaomei KANG Shumei School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051China

Dynamic compression tests were carried out to investigate dynamic mechanical behavior and adiabatic shear bands in ultrafine grained(UFG)pure zirconium prepared by equal channel angular pressing(ECAP)and rotary *** cylindrical specimens were deformed dynamically on the split Hopkinson pressure bar(SHPB)at different strain rates of 800 to 4000s^-1 at room *** temperature distribution of the shear bands was estimated on the basis of temperature rise of uniform plastic deformation stage and thermal diffusion *** results show that the true stress-true strain curves of UFG pure zirconium are concave upward trend of strain in range of 0.02-0.16 due to the effects of strain hardening,strain rate hardening and thermal *** formation of the adiabatic shear bands is the main reason of UFG pure zirconium failure.A large number of micro-voids are observed in the adiabatic shear bands,and the macroscopic cracks develop from the micro-voids *** fracture surface of UFG pure zirconium exhibits quasi cleavage fracture with the characteristic features of shear dimples and river *** highest temperature within the shear bands of UFG pure zirconium is about 592 K.

关键词： ultrafine grained pure zirconium dynamic compression adiabatic shear bands thermal diffusion

Using X-ray computed tomography and micro-Raman spectrometry to measure individual particle surface area, volume, and morphology towards investigating atmospheric heterogeneous reactions

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Journal of Environmental sciences 2018年第7期30卷 23-32页

作者： Mingjin Wang Nan Zheng Tong Zhu Jing Shang Ting Yu Xiaojuan Song Defeng Zhao Yong Guan Yangchao Tian BIC-ESAT and SKL-ESPCl College of Environmental Sciences and Engineering Peking University Beijing 100871 China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029 China

Heterogeneous reactions on the aerosol particle surface in the atmosphere play important roles in air pollution, climate change, and global biogeochemical cycles. However, the reported uptake coefficients of heterogeneous reactions usually have large variations and may not be relevant to real atmospheric conditions. One of the major reasons for this is the use of bulk samples in laboratory experiments, while particles in the atmosphere are suspended individually. A number of technologies have been developed recently to study heterogeneous reactions on the surfaces of individual particles. Precise measurements on the reactive surface area, volume, and morphology of individual particles are necessary for calculating the uptake coefficient, quantifying reactants and products, and understanding the reaction mechanism better. In this study, for the first time we used synchrotron radiation X-ray computed tomography（XCT） and micro-Raman spectrometry to measure individual CaCO_3 particle morphology, with sizes ranging from 3.5–6.5 μm. Particle surface area and volume were calculated using a reconstruction method based on software threedimensional（3-D） rendering. The XCT was first validated with high-resolution fieldemission scanning electron microscopy（FE-SEM） to acquire accurate CaCO_3 particle surface area and volume estimates. Our results showed an average difference of only 6.1% in surface area and 3.2% in volume measured either by micro-Raman spectrometry or X-ray tomography. X-ray tomography and FE-SEM can provide more morphological details of individual Ca CO3 particles than micro-Raman spectrometry. This study demonstrated that X-ray computed tomography and micro-Raman spectrometry can precisely measure the surface area, volume, and morphology of an individual particle.

关键词： Heterogeneous reactions Individual CaCO3 particle Micro-Raman spectrometry Synchrotron radiation X-ray computed tomography Morphology Surface area Volume