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Changes in Temporal Concentration Property of Summer Precipitation in China during 1961–2010 Based on a New Index

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Journal of Meteorological Research 2017年第2期31卷 336-349页

作者： Hui LI Panmao ZHAI er LU Wei ZHAO yang CHEN huan WANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044 Chinese Academy of Meteorological Sciences Beijing 100081

Based on the property of entropy,a new index Q was defined to measure the temporal concentration property of summertime daily rainfall in China,based on daily precipitation data collected at 553 observation stations in China during 1961–***,changes in the temporal concentration property of summer precipitation in China were *** results indicate that the regions with larger Q values were located in most parts of Northwest China and the north of the Yellow River,where daily precipitation tended to become temporally concentrated during the study *** the contrary,smaller Q values were found in eastern Tibetan Plateau,southeastern Northwest China,and most parts of Southwest and South *** most obvious increasing trend of Q index was found in South China and most parts of Southwest China,where precipitation showed a temporal concentration ***,a decreasing trend of Q index was found in Northwest China,the Tibetan Plateau,and the north of the Huaihe *** of the Q index and the summer rainfall total during 1961–2010 in China both exhibited an increasing trend,implying larger temporal variability in rainfall *** is illustrated that the summer precipitation in general became more temporally concentrated with more intense rainfall events and wetter days.

关键词： precipitation temporal concentration Q index climate change

The Shackling Effect in Cyclic Azobenzene Liquid Crystal

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Chinese Journal of Polymer Science 2022年第6期40卷 584-592页

作者： yang Xiao Chong He Zi-Fan yang er-Qiang Chen huan-Jun Lu Xiao-Hong Li Ying-Feng Tu State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of ChemistryPeking UniversityBeijing 100871China Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou 215009China

We demonstrate here a novel method for the design of liquid crystals(LCs)via the cyclization of mesogens by flexible *** two azobenzene-4,4′-dicarboxylate derivatives,the cyclic dimer,cyclic bis(tetraethylene glycol azobenzene-4,4′-dicarboxylate)(CBTAD),shows LC properties with smectic A phase,while its linear counterpart,bis(2-(2′-hydroxyethyloxy))ethyl azobenzene-4,4′-dicarboxylate(BHAD),has no LC *** difference is ascribed to the shackling effect from the cyclic topology,which leads to the much smaller entropy change during phase transitions and increases the isotropic temperature greatly for *** addition,the trans-to-cis isomerization of azobenzene groups under UVlight is also limited in *** the reversible isomerization of azobenzene groups,CBTAD showed interesting isothermal phase transition behaviors,where the LC phase disappeared upon photoirradiation of 365 nm UV-light,and recovered when the UV-light was *** with the smectic LC nature,a novel UV-light tuned visible light regulator was designed,by simply placing CBTAD in two glass *** scattered phase of smectic LC was utilized as the“OFF”state for light passage,while the UV-light induced isotropic phase was utilized as the“ON”*** shackling effect outlined here should be applicable for the design of cyclic LC oligomers/polymers with special properties.

关键词： Azobenzene Cyclic Liquid crystals Isothermal phase transition

Neural Parse Combination

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Journal of Computer Science & Technology 2017年第4期32卷 749-757页

作者： Lin-er yang Mao-Song Sun Yong Cheng Jia-Cheng Zhang Zheng-Hao Liu huan-Bo Luan yang Liu Department of Computer Science and Technology Tsinghua University Beijing 100084 China State Key Laboratory of Intelligent Technology and Systems Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China Jiangsu Collaborative Innovation Center for Language Ability Jiangsu Normal University Xuzhou 221009 China Institute for Interdisciplinary Information Sciences Tsinghua University Beijing 100084 China

Analyzing the syntactic structure of natural languages by parsing is an important task in artificial intelligence. Due to the complexity of natural languages, individual parsers tend to make different yet complementary errors. We propose a neural network based approach to combine parses from different parsers to yield a more accurate parse than individual ones. Unlike conventional approaches, our method directly transforms linearized candidate parses into the ground-truth parse. Experiments on the Penn English Treebank show that the proposed method improves over a state-of-the-art parser combination approach significantly.

关键词： neural network parsing parse combination

Effect of Al2O3/SiO2 and CaO/Al2O3 ratios on wettability and structure of CaO-SiO2-Al2O3-based mold flux system

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Journal of Iron and Steel Research International 2019年第4期26卷 355-364页

作者： Wan-lin Wang er-zhuo Gao Le-jun Zhou Lei Zhang huan Li School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina National Center for International Research of Clean Metallurgy Central South UniversityChangsha 410083HunanChina

The effect of Al2O3/SiO2 and CaO/Al2O3 ratios on the molten structure of CaO-SiO2-Al2O3-based mold flux system was analyzed by Fourier transform infrared spectroscopy,Raman spectroscopy,and X-ray photoelectron ***,the variation in the wettability between the mold flux system and an interstitial free(IF)steel substrate was investigated using the sessile drop *** results indicate that the contact angle and interfacial tension between the molten slag and solid steel increase slightly with the increase in the Al2O3/SiO2 ratio,while they decrease with the increase in the CaO/Al2O3 *** network structure for the designed mold flux system changes gradually from silicate to aluminosilicate and aluminate with the increase in the Al2O3/SiO2 ratio,and the network is simplified with the increase in the CaO/Al2O3 ***,combining the results of sessile drop method and melt structure analyses,it suggests that the variation in interfacial properties of mold flux/IF steel substrate is mainly caused by the change in melt structure,especially the variation in free oxygen ions(O^2-)and non-bridged oxygen(O^-)at the interface.

关键词： Wettability Melt structure Interfacial tension Sessile drop method Mold flux system

Benefits Comparison Analysis of Diferent Rice and Wheat Cropping Patterns to Adapt to Climate Change

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Advances in Climate Change Research 2013年第3期4卷 182-189页

作者： huanG huan-Ping MA Shi-Ming LIN er-Da LI Ying-Chun ZhuanG Heng-yang Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Environment Ministry of Agriculture Agricultural College Yangzhou University

Based on the input-output survey of farmers and experts in one of the Jiangsu GEF project areas,the Cost-Benefit analysis method and greenhouse gas estimation method recommended by IPCC were applied to evaluate and compare the social,economic and ecological benefits of artificial transplanting(ATR),mechanical transplanting(MTR)and direct seeding(DSR)rice under wheat-rice Double Late mode(late rice harvest and late wheat sowing).Results showed that the MTR and DSR rice achieved obvious social *** measures resulted in excessive emission of anthropogenic greenhouse *** the use of ATR rice and wheat rotation mode it is possible to obtain most economic and ecological *** Double Late mode of action had good application prospects,but the key to implementation was the timely exploitation of the recently increased availability of agricultural climate *** cropping pattern of combining the wheat-rice Double Late mode with the ATR was a better choice in mitigating and adapting to climate change.

关键词： climate change adaptation yield benefit greenhouse gas emissions

High-performance and fabrication friendly polarization demultiplexer

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Chinese Physics B 2022年第3期31卷 265-268页

作者： huan Guan yang Liu Zhiyong Li State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100083China

A compact and fabrication friendly polarization demultiplexer(P-DEMUX) is proposed and characterized to enable wavelength-division-multiplexing and polarization-division-multiplexing simultaneously. The proposed structure is composed of a polarization-selective microring resonator in ultrathin waveguide and two bus channels in the silicon nitridesilica-silicon horizontal slot waveguides. In the slot waveguide, the transverse electric(TE) mode propagates through the silicon layer, while the transverse magnetic(TM) mode is confined in the slot region. In the designed ultra-thin waveguide, the TM mode is cut-off. The effective indexes of the TE modes for ultrathin and slot waveguides have comparable values. Thanks for these distinguishing features, the input TE mode can be efficiently filtered through the ultra-thin microring at the resonant wavelength, while the TM mode can directly output from the through port. Simulation results show that the extinction ratio of the proposed P-DEMUX for TE and TM modes are 33.21 dB and 24.97 dB, and the insertion losses are 0.346 dB and 0.324 dB, respectively, at the wavelength of 1551.64 nm. Furthermore, the device shows a broad bandwidth(> 100 nm) for an extinction ratio(er) of > 20 dB. In addition, the proposed P-DEMUX also has a good fabrication tolerance for the waveguide width variation of-20 nm≤ △w_(g)≤ 20 nm and the microring width variation of -20 nm≤ △w_(r) ≤20 nm for a low insertion loss of er of <-18 dB.

关键词： polarization demultiplexers wavelength-division-multiplexing microring resonators

Selective recognition of aromatic hydrocarbons by endo-functionalized molecular tubes via C/N-H…π interactions

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Chinese Chemical Letters 2018年第1期29卷 91-94页

作者： Guo-Bao huang Wei-er Liu Arto Valkonen huan Yao Kari Rissanen Wei Jiang College of Chemistry and Food Science Yulin Normal University College of Chemistry and Environmental Engineering Shenzhen University Department of Chemistry South University of Science and Technology of China Department of Chemistry and Nanoscience Center University of Jyvaskyla

Molecular recognition of aromatic hydrocarbons by four endo-functionalized molecular tubes has been studied by 1H NMR spectroscopy, computational methods, and single crystal X-ray crystallography. The binding selectivity is rationalized by invoking shape complementarity and dipole alignment. The non- covalent interactions are proved to predominantly be C/N-H...π interactions.

关键词： MacrocyclesAromatic hydrocarbonMolecular recognitionHost-guest chemistryHydrogen bond

Novel insights into necrozoospermia from a single-center study:reference ranges,possible etiology,and impact on male fertility

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Asian Journal of Andrology 2024年第5期26卷 528-534页

作者： er-Chen Zhang Xin-Yu Yin Zi-Yan Peng Zhi-Zhou Lai Liang Hu yang-Qin Peng huan Zhang Rui Ming Ge Lin Wei-Na Li NHC Key Laboratory of Human Stem Cell and Reproductive Engineering School of Basic Medical SciencesCentral South UniversityChangsha 410008China Laboratory of Zebrafish Genetics College of Life SciencesHunan Normal UniversityChangsha 410006China Hunan Guangxiu Hospital School of MedicineHunan Normal UniversityChangsha 410001China Clinical Research Center for Reproduction and Genetics in Hunan Province Reproductive and Genetic Hospital of CITICXiangyaChangsha 410008China Hunan International Scientific and Technological Cooperation Base of Development and Carcinogenesis Changsha 410008China Hunan Guangxiu Hi-tech Life Technology Co. Ltd.Changsha 410013China

Necrozoospermia is a poorly documented condition with a low incidence,and its definition and clinical significance are ***,we provide a reference range for necrozoospermia and discuss its possible etiology and impact on male fertility and assisted reproductive *** extracted relevant information from 650 Chinese male partners of infertile couples and statistically analyzed sperm *** was present in 3.4%(22/650)of our study population,and the lower cut-off value for sperm vitality was 75.3%.We compared two methods for assessing sperm vitality(eosin-nigrosin head staining and hypo-osmotic swelling test[HOST]),for which the percentage in the eosin-nigrosin group(mean±standard deviation[s.d.]:77.5%±10.5%)was significantly higher than that in the HOST group(mean±s.d.:58.1%±6.7%[5-10 min after incubation]and 55.6%±8.2%[25-30 min after incubation];both Permia increased with age(odds ratio[OR]=1.116,95%confidence interval[CI]:1.048-1.189,P=0.001),while the percentage of normal sperm morphology and DNA fragmentation index(DFI)were significantly associated with necrozoospermia,with ORs of 0.691(95%CI:0.511-0.935,P=0.017)and 1.281(95%CI:1.180-1.390,Permia group and 87 patients in the necrozoospermia group to compare intracytoplasmic sperm injection(ICSI)and pregnancy outcomes between the two *** necrozoospermia group had a significantly lower normal fertilization rate(74.7%vs 78.2%,P=0.041;OR=0.822;95%CI:0.682-0.992)than that in the nonnecrozoospermia *** study presents substantial information on necrozoospermia to establish comprehensive and applicable reference values for sperm vitality for spontaneous conception and artificially assisted reproductive management.

关键词： male fertility necrozoospermia reference ranges sperm vitality

Fabrication and analysis of TIG welding-brazing butt joints of in-situ TiB2/7050 composite and TA2

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Defence Technology（防务技术） 2021年第3期17卷 1062-1070页

作者： huan-huan Sun Yi-bo Ren yang Feng Hao-qiang Ba Dong Chen Chun-juan Xia Hao-wei Wang School of Materials Science&Engineering Shenyang Ligong UniversityShenyangChina School of Materials Science&Engineering Shanghai Jiao Tong UniversityShanghaiChina

Lightweight hybrid structures of Al MMCs and titanium alloy dissimilar materials have great prospect in the defence industry application. So, it is necessary to join Al MMCs with Ti metal to achieve this structural design. In this work, in-situ Ti B_(2)/7050 composite and TA2 were firstly attempted to join by TIG welding-brazing technique. The result was that the intact welding-brazing butt joint was successfully fabricated. The joint presents dual characteristics, being a brazing on TA2 side and a welding on Ti B_(2)/7050 side. At brazing joint side, er4043 filler metal effectively wets on TA2 under TIG heating condition,and a continuous interfacial reaction layer with 1 e3 mm is formed at welded metal/TA2 interface. The whole interfacial reaction layers are composed of Ti(Al Si)3 intermetallic compounds(IMCs), but their morphologies at the different regions present obvious distinguishes. The microhardness of the reaction layers is as much as 141 e190 HV. At welding joints side, the fusion zone appears the equixaed crystal structure, and the grain sizes are much smaller than those of welded metal, which is attributed to the effect of Ti B2 particulates from the melted Ti B_(2)/7050 on acceleration formation and inhibiting growth for the new crystal nucleus. The tensile test results show that average tensile strength of the optimal welding-brazing joint is able to achieve 138 MPa. The failure of the tensile joint occurs by quasi-cleavage pattern, and the cracks initiate from the IMCs layer at the groove surface of TA2 and propagate into the welded metal.

关键词： In-situ TiB2/7050 composite TA2 TIG welding-brazing Fabrication Analysis