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Spatial differentiation in stable isotope compositions of surface waters and its environmental significance in the Issyk-Kul Lake region of Central Asia

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Journal of Mountain Science 2018年第2期15卷 254-263页

作者： MA Long JIlili Abuduwaili li yao-ming State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011 China

Stable isotope values of oxygen （180） and hydrogen （2H） of surface waters were used to study the origin and environmental significanees in the Issyk-Kul basin of Kyrgyzstan in Central Asia, which is the most important intermountain basin in the modern Tien Shan orogen. This study is the first analysis of hydrochemical spatial differentiation in the stable isotopes of surface waters in this watershed. 75 samples were collected from rivers, springs, lakes, rain and snow during the rainy season in July and August of 2o16. Stable isotopes of 180 and 2H were studied for all samples, and cation ratios （Sr/Ca and Mg/Ca） were also determined for lake water samples. Stable isotope values from precipitation scattered around the Local Meteoric Water line （determined from Urumqi Station of the global network of isotopes in precipitation （GNIP））, together with values of the Deuterium excess parameter （d） from 15.3‰ to 30.5‰, with an average of 19.8‰, indicating that the moisture sources are primarily from regions with low relative humidity. The 8180 and 52H values were significantly different between the river and lake samples, indicating that regional evaporation caused the isotopic enrichment of lake water. Geospatial autocorrelation, measured by Moran＇s I coefficient, indicated weak spatial autocorrelation within stable isotopes of oxygen and hydrogen in the surface waters of the studied area, which is primarily an effect of climate during the water chemistry evolution. The cation ratios Sr/Ca and Mg/Ca in lake water samples were not correlated with the concentration of total dissolved solids, but did show correlation with stable isotopic values, which is significant for paleoenvironmental reconstruction.

关键词： Spatial differentiation Stable isotope Moisture Sources Geospatial autocorrelation IssykKul Lake Central Asia

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Dynamic Recrystallization of Hot Deformed 3Cr2NiMnMo Steel:Modeling and Numerical Simulation

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Journal of Iron and Steel Research International 2013年第11期20卷 98-104页

作者： li Xia WU Xiao-chun ZHANG Xiao-xun li ming-yao School of Materials Science and Engineering Shanghai University School of Materials Engineering Shanghai University of Engineering Science

Hot compression tests of 3Cr2NiMnMo steel were performed at temperatures in the range of 850 to 1 100 ℃ and with strain rates of 10 ^-2 s^- 1 to 1 s ^-1. Both the constitutive equations and the hot deformation activation energy were derived from the correlativity of flow stress, strain rate and temperature. The mathematical models of the dynamic recrystaIiization of 3Cr2NiMnMo steel, which inelude the dynamic recrystallization kinetics model and the crystalliza- tion grain size model, are based on Avrami＇s law and the results of thermosimulation experiments. By integrating de- rived dynamic recrystallization models with the thermal mechanical coupled finite element method, the microstruc ture evolution in hot compressive deformation was simulated. The distribution of dynamic recrystallization grains and grain sizes were determined through a comparison of the simulation results with the experimental results. The distri- bution of strain and dynamic recrystallization grain is also discussed. The similarity between the experimental results and the simulated results indicates that the derived dynamic recrystallization models can be applied effectively to pre diet and analyze the microstructure evolution in hot deformed 3Cr2NiMnMo steel.

关键词： dynamic recrysta[hzation 3Cr2NiMnMo steel hot forming microstructure evolution numerical simulation

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Numerical study on morphological characteristics of rotational natural supercavitation by rotational supercavitating evaporator with optimized blade shape

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Journal of Hydrodynamics 2020年第3期32卷 468-485页

作者： Zhi-ying Zheng Qian li Lu Wang li-ming yao Wei-hua Cai Hui li Feng-chen li School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Department of Nuclear Engineering Kyoto UniversityKyotoJapan College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China Institute of Advanced Technology Heilongjiang Academy of SciencesHarbin 150020China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

In view of the supercavitation effect, a novel device named the rotational supercavitating evaporator (RSCE) has been designed for the desalination. In order to improve the blade shape of the rotational cavitator in the RSCE for the performance optimization, the blade shapes of different sizes are designed by utilizing the improved calculation method for the blade shape and the validated empirical formulae based on previous two-dimensional numerical simulations, from which the optimized blade shape with the wedge angle of 45° and the design speed of 5 000 r/min is selected. The estimation method for the desalination performance parameters is developed to validate the feasibility of the utilization of the results obtained by the two-dimensional numerical simulations in the design of the three-dimensional blade shape. Three-dimensional numerical simulations are then conducted for the supercavitating flows around the rotational cavitator with the optimized blade shape at different rotational speeds to obtain the morphological characteristics of the rotational natural supercavitation. The results show that the profile of the supercavity tail is concaved toward the inside of the supercavity due to the re-entrant jet. The empirical formulae for estimating the supercavity size with consideration of the rotation are obtained by fitting the data, with the exponents different from those obtained by the previous two-dimensional numerical simulations. The influences of the rotation on the morphological characteristics are analyzed from the perspectives of the tip and hub vortices and the interaction between the supercavity tail and the blade. Further numerical simulation of the supercavitating flow around the rotational cavitator made up by the blades with exit edge of uniform thickness illustrate that the morphological characteristics are also affected by the blade shape.

关键词： Rotational natural supercavitation morphological characteristics blade shape computational fluid dynamics(CFD)numerical simulation rotational supercavitating evaporator

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Theoretical study on the reaction of VS^+(~3∑^-,~1Γ)with CO

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Chinese Chemical Letters 2008年第8期19卷 1008-1011页

作者： Shi Wen Yu li Qing Yin li Feng yao ming li Xiao Guang Xie Department of Chemistry Yunnan University Kunming 650091 China

Two possible reaction mechanisms of VS^＋（^3∑^-, 1^Г） with CO in the gas phase have been studied by using B3LYP/TZVP and CCSD（T）/6-311＋G （3df, 3pd） methods： the O/S exchange reaction （VS^＋＋CO→VO^＋＋CS） and the S-transfer reaction （VS^＋＋ CO → V^＋＋ COS）. The two reactions proceed via two-step and one-step mechanism, respectively. The barriers of the triplet and singlet PESs are 30.6 and 50.9 kcal/mol, respectively, for O/S exchange reaction and 7.3 and 50.2 kcal/mol, respectively, for the S-transfer reaction. The results indicate that the triplet ground state reaction is more favorable, and the S-transfer reaction is more favorable than the O/S exchange reaction, which is in good agreement with the experimental observation.

关键词： Vanadium sulfide ion CO Reaction CCSD(T)

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Vegetation dynamics and climate variability over the past 2000 years inferred from Son Kul marsh in the western Tianshan Mountains

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Journal of Mountain Science 2021年第5期18卷 1246-1255页

作者： ZHANG Dong-liang li yao-ming li Kai-hui MA Xue-xi YANG Yun-peng State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China College of Environment and Planning Henan UniversityKaifeng 475004China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Ministry of Education) Henan UniversityKaifeng 475004China

A pollen study was conducted on an alpine marsh sediment in the Son Kul Basin and was allowed to reconstruct changes in vegetation dynamics and climatic information in the western Tianshan Mountains during the past 2000 *** diagram reveals that regional vegetation is dominated by alpine meadow in the past 2000 years,being similar with modern vegetation components in the *** Artemisia/Chenopodiaceae-indicated moisture exhibits a warm-dry Roman Warm Period(RWP,~0-~500 AD),a cold-dry Dark Ages Cold Period(DACP,~500-~800 AD),a warm-wet Medieval Warm Period(MWP,~800-~1350 AD),a cold-dry little Ice Age(liA,~1350-~1850 AD)and a warm-dry Current Warm Period(CWP,since~1850 AD).Our pollen-based moisture reconstructions are supported by other nearby moisture *** with other pollen data in the western Tianshan Mountains,we found that the vegetation was relatively stable before~1650-~1750 AD and the anthropogenic activities obviously intensified afterwards(especially at the middle-elevation sites).Further work involving more and higher-resolution palaeovegetation records would contribute to fully understand the information on the complex links between environmental,climatic and anthropogenic changes in the western Tianshan Mountains.

关键词： Pollen analysis Past 2000 years Son Kul marsh Kyrgyzstan Central Asia

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阿勒泰地区草地植物丰度与地上生物量分布特征及其影响因素

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草地学报 2025年第2期33卷 586-595页

作者：惠婷婷郑红玉范连连毛洁菲马学喜李耀明中国科学院新疆生态与地理研究所新疆乌鲁木齐830011 新疆巴里坤县林业和草原工作站新疆巴里坤839200 中国科学院中亚生态与环境研究中心新疆乌鲁木齐830011 中国科学院大学北京100049

为应对气候变化和人类活动加剧对新疆阿勒泰地区草地生态系统结构功能的影响,促进该区域草地生态系统的可持续发展。本研究基于2022年61个样点共183个野外1 m×1 m样方调查,结合气候与环境因子数据,探究了阿勒泰地区草地物种丰富度(Spec... 详细信息

为应对气候变化和人类活动加剧对新疆阿勒泰地区草地生态系统结构功能的影响,促进该区域草地生态系统的可持续发展。本研究基于2022年61个样点共183个野外1 m×1 m样方调查,结合气候与环境因子数据,探究了阿勒泰地区草地物种丰富度(Species richness,SR)和地上生物量(Aboveground biomass,AGB)分布特征及其影响因素。结果表明:本次调查共记录植物183种,分属35科121属,禾本科、菊科、蔷薇科为阿勒泰地区草地优势科。SR和AGB随着纬度或海拔的升高显著增加,北部山区SR高于南部荒漠区,且二者与年均降水量、年均温度显著相关。SR与土壤C/N、C/P显著正相关,AGB与土壤化学计量比无显著相关关系。RDA分析结果表明纬度对阿勒泰地区草地SR和AGB的解释率最大,为24.1%,其次为气温年较差、年均温度、年均降水量和经度,解释率分别为8.7%,6.1%,5.4%和4.2%。综上,新疆阿勒泰地区草地植物群落物种资源较丰富,SR和AGB分布主要受经纬度、气温年较差、年均温度、年均降水量的影响,未来还需进一步量化放牧强度的影响。

关键词：物种丰富度地上生产力地形因子水热因子土壤化学计量比

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Novel Catalytic Method for Synthesis of Glycosyl Esters by Combining PTC with DMAP

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Chemical Research in Chinese Universities 2007年第4期23卷 426-429页

作者： YANG Song-tao ZHANG Suo-qin ZHANG Guang-liang WANG Xiao-ming li yao-xian College of Chemistry Jilin University Changchun 130021 P. R. China

This article presents a novel catalytic method by combining phase-transfer catalyst, benzyltriethylammonium chloride, with 4-dimethylaminopyridine for the syntheses of glycosyl esters from substituted phenoxyaeetie acids and the peracetate of α-D-l-bromosugars to produee eight novel β-glyeosyl esters in high yields. The struetures of the syn-thesized eompounds were established by IR, MS, ^1H NMR, and ^13C NMR speetra and elemental analyses.

关键词： Glycosyl ester Substituted phenoxyacetic acid Phase-transfer catalyst 4-Dimethylaminopyridine

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Cutaneous and systemic plasmacytosis

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Chinese Medical Journal 2012年第22期125卷 4156-4157页

作者： CHENG Ru-hong YU Hong li ming yao Zhi-rong Shanghai Jiao Tong Univ Dept Dermatol Xinhua Hosp Sch Med Shanghai 200092 Peoples R China

Cutaneous and systemic plasmacytosis （CSP） is a rare condition characterized by a clinical triad of cutaneous lesions, polyclonal hypergammaglobulinemia, and superficial lymphadenopathy. The condition is described primarily in middle-aged Asian patients and particular in Japanese individuals,l A previous study suggest a male ： female ratio of 1 to 0.6, and an age of onset ranging from 20 to 62 years, with both a mean and median age of 37 years.2 Here, we report a Chinese case of CSP, who is the youngest patient of Chinese decent in literature.

关键词： cutaneous and systemic plasmacytosis Chinese

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Synthesis, spectroscopic properties, and tautomerism of mono-meso-substituted octamethylporphyrins

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Chinese Journal of Chemistry 1994年第3期12卷 237-242页

作者： li, ming yao, Yi-ming ZOU, Jian-Zhong XU, Zheng YOU, Xiao-ZengCoordination Chemistry Institute, Coordination Chemistry State Key Laboratory, Nanjing University,Nanjing, Jiangsu 210008, China Coordination Chemistry Institute Coordination Chemistry State Key Laboratory Nanjing University Nanjing Jiangsu 210008 China

The synthesis spectroscopic properties and tautomerism of four novel mono-meso substituted(R)-octamethylporphyrins (R=o-hydroxybenzyl, p-aminobenzyl, 4-pyridinyl, and ferro-cenyl) were investigated. It was found that the porphyrins 2, 3 could be directly prepared in good yields via the coupling reaction of salicylaldehyde and p-aminobenzyl aldehyde with octamethyl-l',8'-dideoxy-ac-biladiene dihydrobromide, respectively. The free energy of activation (G) of the tautomerism of the porphyrins was calculated and interpreted in terms of electronic and steric nature. In contrast with 2-substituted-5,10,15,20-tetraphenylporphyrins, the substituents in meso position do not change the relative amount of two tautomers a and 6.

关键词： Mono-meso-substituted octamethylporphyrins spectroscopy tautomerisra.

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Sequential Extraction of Natural Surface Coatings: Comparison with Single Stage Extraction and Its Application in Investigating Adsorption Characteristics of Surface Coating Components for Metals

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Chemical Research in Chinese Universities 2012年第1期28卷 41-46页

作者： HUA Xiu-yi, liU Xiao-xue, DONG De-ming, li ming and li yao-rui Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Key Lab of Water Resources and Aquatic Environment of Jilin Province, College of Environment and Resources, Jilin University, Changchun 130012, P. R. China College of Environment and Resources Jilin University Key Laboratory of Groundwater Resources and Environment Ministry of Education Key Lab of Water Resources and Aquatic Environment of Jilin Province Changchun 130012

Multistage sequential extraction with different sequences was applied to extracting natural surface coa tings（NSCs）, and the results were compared with those by single stage extraction technique. The optimal sequential extraction scheme with the best performance was selected and incorporated into the method of selective extraction followed by adsorption and statistic analyses to study the adsorption parameters of Fe oxides, Mn oxides and organic matters in NSCs for Pb and Cd, to validate the applicability of the sequential extraction scheme. The Langmuir ad sorption parameters of each component of surface coating estimated according to the adsorption data of single stage extraction of NSCs were all similar to those of sequential extraction of NSCs, and the maximum difference between the metal adsorption abilities of the components estimated via the two extraction techniques was only about 20%, in dicating that either extraction techniques could be used. The optimal sequential extraction scheme obtained was first extracted with NH2OH·HCl, then with Na2S2O4, and finally with oxalic acid.

关键词： Natural surface coating(NSC) Sequential extraction Single stage extraction Adsorption Component

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