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Science China Chemistry 2025年第1期68卷 394-402页

作者： Zhiqiang Ding Mingqian wang Zijing Zhou bin wang Yuesheng Li Tianjin Key Laboratory of Composite & Functional Materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of L-lactide is a promising approach to isotactic-rich and crystalline poly（L-lactide）.In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

关键词： organic ion pair controlled cationic ring-opening polymerization activated chain end mechanism isotactic-rich polylactide

Standing-wave spectrometry in silicon nano-waveguides using reflection-based near-field scanning optical microscopy

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Chinese Physics B 2019年第1期28卷 306-312页

作者： Yi-Zhi Sun Wei Ding bin-bin wang Rafael Salas-Montiel Sylvain Blaize Renaud Bachelot Zhong-Wei Fan Li-Shuang Feng School of Instrumentation Science and Opto-Electronics Engineering Beihang University Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Laboratoire de Nanotechnologie et d’Instrumentation Optique(LNIO)ICD CNRS UMR 6281 Universitéde Technologie de Troyes Academy of Opto-Electronics Chinese Academy of Science

Utilizing reflection-based near-field scanning optical microscopy(NSOM) to image and analyze standing-wave patterns, we present a characterization technique potentially suitable for complex photonic integrated circuits. By raster scanning along the axis of a straight nano-waveguide in tapping mode and sweeping wavelength, detailed information of propagating waves in that waveguide has been extracted from analyses in both space and wavelength domains. Our technique needs no special steps for phase stabilization, thus allowing long-duration and environment-insensitive measurements. As a proof-of-concept test, in a silicon single-mode waveguide with a few of etched holes, the locations and reflection strengths of the inner defects have been quantified. The measurement uncertainty of the reflection amplitude is less than 25% at current stage. Our technique paves the way for non-destructively diagnosing photonic circuits on a chip with sub-wavelength spatial resolution and detailed information extraction.

关键词： near-field scanning optical microscopes integrated optics interferometry

Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges

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Advances in Climate Change Research 2024年第3期15卷 367-389页

作者： Hao wang bin-bin wang Peng CUI Yao-Ming MA Yan wang Jian-Sheng HAO Yu wang Ya-Mei LI Li-Jun SUN Jiao wang Guo-Tao ZHANG Wei-Mo LI Yu LEI Wen-Qing ZHAO Jin-Bo TANG Chao-Yue LI Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China China‒Pakistan Joint Research Center on Earth Sciences Chinese Academy of SciencesIslamabad 45320Pakistan College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China National Observation and Research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Dingri 858200China

High Mountain Asia(HMA)shows a remarkable warming tendency and divergent trend of regional precipitation with enhanced meteorological *** rapid thawing of the HMA cryosphere may alter the magnitude and frequency of nature *** reviewed the influence of climate change on various types of nature hazards in HMA region,including their phenomena,mechanisms and *** reveals that:1)the occurrences of extreme rainfall,heavy snowfall,and drifting snow hazards are escalating;accelerated ice and snow melting have advanced the onset and increased the magnitude of snowmelt floods;2)due to elevating trigger factors,such as glacier debuttressing and the rapid shift of thermal and hydrological regime of bedrock/snow/ice interface or subsurface,the mass flow hazards including bedrock landslide,snow avalanche,ice-rock avalanches or glacier detachment,and debris flow will become more severe;3)increased active-layer detachment and retrogressive thaw slumps slope failures,thaw settlement and thermokarst lake will damage many important engineering structures and infrastructure in permafrost region;4)multi-hazards cascading hazard in HMA,such as the glacial lake outburst flood(GLOF)and avalanche-induced mass flow may greatly enlarge the destructive power of the primary hazard by amplifying its volume,mobility,and impact force;and 5)enhanced slope instability and sediment supply in the highland areas could impose remote catastrophic impacts upon lowland regions,and threat hydropower security and future water *** future,ongoing thawing of HMA will profoundly weaken the multiple-phase material of bedrock,ice,water,and soil,and enhance activities of nature *** and cascading hazards of high magnitude will prevail in *** the glacier runoff overpasses the peak water,low flow or droughts in lowland areas downstream of glacierized mountain regions will became more frequent and *** escalating hazards in the HMA region requires tackling s

关键词： High Mountain Asia Climate change Cryosphere degradation Nature hazards Disaster risk

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng wang Qinyi Guo bin Hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

An association study of HFEgene mutation with idiopathic male infertility in the Chinese Han population

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Asian Journal of Andrology 2012年第4期14卷 599-603页

作者： Xiao-Ying Yu bin-bin wang Zhong-Cheng Xin Tao Liu Ke Ma Jian Jiang Xiang Fang Li-Hua Yu Yi-Feng Peng Xu Ma Institute of Reproductive Medicine Yijishan HospitalWannan Medical CollegeWuhu 241001China National Research Institute for Family Planning Beijing 100081China peking Union Medical College Beijing 100081China Andrology Center Peking University First HospitalBeijing 100034China World Health Organization Collaborating Centre for Research in Human Reproduction Beijing 100081China

Mutations in the haemochromatosis gene （HFE） influence iron status in the general population of Northern Europe, and excess iron is associated with the impairment of spermatogenesis. The aim of this study is to investigate the association between three mutations （C282Y, H63D and S65C） in the HFEgene with idiopathic male infertility in the Chinese Han population. Two groups of Chinese men were recruited： 444 infertile men （including 169 with idiopathic azoospermia） and 423 controls with proven fertility. The HFEgene was detected using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） technique. The experimental results demonstrated that no C282Y or $65C mutations were detected. Idiopathic male infertility was not significantly associated with heterozygous H63D mutation （odds ratio=O.801, 95% confidence interval=0.452-1.421, X2=0.577, P=0.448）. The H63D mutation frequency did not correlate significantly with the serum luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and testosterone （T） levels in infertile men （P=0.896, P=0.404 and P=O.05, respectively）. Our data suggest that the HFEH63D mutation is not associated with idiopathic male reproductive dysfunction.

关键词： gene mutation gonadotropic hormone HFE male infertility

Hydrogen-induced amorphization of Zr-Cu-Ni-Al alloy

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China Foundry 2017年第2期14卷 145-150页

作者： Fu-yu Dong Song-song Lu Yue Zhang Qing-chun Xiang Hong-jun Huang Xiao-guang Yuan Xiao-jiao Zuo Liang-shun Luo Yan-qing Su bin-bin wang School of Materials Science and Engineering Shenyang University of Technology School of Materials Science and Engineering Harbin Institute of Technology

Arc melting was utilized in this study to produce Zr_(55)Cu_(30)Ni_5Al_(10) alloys under mixed atmospheres with various ratios of high-purity hydrogen to argon. The influences of hydrogen addition on the solidification structure and glass-forming ability of Zr_(55)Cu_(30)Ni_5Al_(10) alloy were determined by examining microstructures in different parts of the cast ingots. The results showed that different degrees of crystallization structures were obtained in the ascast button ingots after arc melting in high-purity Ar, and the cross-sectional solidification morphology of arcmelted ingots was found to consist of crystals with varying from the bottom up. By contrast, there were completely amorphous structures in the middle and upper areas of the as-cast button ingots fabricated by adding 10% H_2 to the high-purity Ar atmosphere. A clear solidification interface was found between the crystal and glass in the ascast button ingots, which indicates that hydrogen addition can enhance the Zr_(55)Cu_(30)Ni_5Al_(10) alloy's glass-forming ability. The precise mechanism responsible for this was also investigated.

关键词： Zr-Cu-Ni-Al alloy melt hydrogenation solidification structure hydrogen-induced amorphization

Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng wang Tao DUAN Kaijie YANG bin YANG Chunmei wang Xin TIAN Qi LU Institute of Ecological Conservation and Restoration Institute of Desertification Studies Chinese Academy of Forestry Institute of Desertification Institute of Desertification Studies Chinese Academy of Forestry Institute of Great Green Wall Satellite Application Centre for Ecology and Environment MEE Institute of Microelectronics Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences Institute of Forest Resource Information Techniques Chinese Academy of Forestry

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution （VHR） unmanned aerial vehicle （UAV） and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover （FWVC） and fractional herbaceous vegetation cover （FHVC） in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error （RMSE） values for the FWVC and FHVC models were 10.69% and 11.67%,and the R2values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10～6 *** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth Sciences 2025年第1期68卷 1-10页

作者： Yongping wang Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU Ze-Jun HU bin LI Key Laboratory for Polar Science Ministry of Natural Resources Polar Research Institute of China Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology School of Earth and Space Sciences University of Science and Technology of China School of Electronic Information Wuhan University

The Medium-energy Electron Spectrometers(MES) is a space-borne instrument onboard Macao Science Satellite-1(MSS-1) dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development, including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch, all within the range of 1.5

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1

Visualizing charge transfer and nuclear quantum effects in the hydrogen bond network of water

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Science China Chemistry 2025年

作者： Ying Gao Haotian wang bin Zhang Department of Chemistry School of Science Tianjin University

Water, one of the most common and important solvents on earth, is widely used in biology, physics, chemistry, and other fields [1]. The hydrogen bond interactions between water molecules form a highly dynamic and syne...

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Effects of magnesium chloride-based multicomponent salts on atmospheric corrosion of aluminum alloy 2024

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Transactions of Nonferrous Metals Society of China 2013年第4期23卷 1199-1208页

作者：王彬彬王振尧韩薇汪川柯伟中国科学院金属研究所金属腐蚀与防护国家重点实验室沈阳110016

Atmospheric corrosion of aluminum alloy 2024 （AA2024） with salt lake water was simulated through a laboratory- accelerated test of cyclic wet-dry and electrochemical techniques. Effects of the soluble magnesium salt contained in the salt water were investigated by scanning electron microscope （SEM）, transmission electron microscope （TEM）, energy dispersive spectrometer （EDS）, electron probe micro analyzer （EPMA）, X-ray diffraction （XRD）, infrared transmission spectroscope （IR）, and atmospheric corrosion monitor （ACM）. The results showed that, with the deposition, atmospheric corrosion of AA2024 could occur when the relative humidity （RH） was lower than 30%. A main crystalline component of corrosion products, layered double hydroxides （LDH）, [Mg1-xAlx（OH）2]^x＋ Clx-·mH2O （LDH-C1）, was determined, which meant that magnesium ion played an important role in the corrosion process. It not only facilitated the corrosion as a result of deliquescence, but also was involved in the corrosion process as a reactant.

关键词： aluminum alloy 2024 atmospheric corrosion magnesium chloride relative humidity corrosion products