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Influence of Sub-Cloud Secondary Evaporation Effects on the Stable Isotopes in Precipitation of Urumqi Glacier No.1,Eastern Tianshan

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Journal of Earth Science 2024年第1期35卷 177-189页

作者： Mengyuan Song zhongqin li Feiteng Wang Xin Zhang State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesTianshan Glaciological StationChinese Academy of SciencesLanzhou 730000China College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730000China College of Sciences Shihezi UniversityShihezi 832000China

In arid regions,the stable hydrogen and oxygen isotopic composition in raindrops is often modified by sub-cloud secondary evaporation when they descend from cloud base to ground through the unsaturated *** a result of kinetic fractionation,the slope and intercept of the δ^(2)H-δ^(18)O correlation equation *** variation of deuterium excess from cloud base to the ground is often used to quantitatively evaluate the influence of secondary evaporation effect on isotopes in *** on the event-based precipitation samples collected at Urumqi Glacier No.1,eastern Tianshan during four-year observation,the existence and impact of secondary evaporation effects were analyzed by the methods of isotope-evaporation *** high air temperature,small raindrop diameter and precipitation amount,and low relative humidity conditions,the remaining rate of raindrops is small and the change of deuterium excess is large relatively,and the slope and intercept of δ^(2)H-δ^(18)O correlation equation are much lower than those of Global Meteoric Water line,which mean that the influence secondary evaporation on precipitation *** on the conditions of low air temperature,high relative humidity,heavy rainfall,and large raindrop diameter,the change of deuterium excess is small relatively and the remaining rate of raindrops is large,and the slope and intercept of δ^(2)H-δ^(18)O correlation equation increase,the secondary evaporation is *** isotope-evaporation model described a good linear correlation between changes of deuterium excess and evaporation proportion with the slope of 0.90‰/%,which indicated that an increase of 1%in evaporation may result in a decrease of deuterium excess about 0.90‰.

关键词： stable isotopes meteoric water line deuterium excess sub-cloud secondary evaporation effect precipitation glaciers

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仿刺参(Apostichopus japonicus)肠道源植物乳杆菌(Lactobacillus plantarum)HY21的生长及益生特性分析

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微生物学报 2024年第3期64卷 840-853页

作者：李忠琴王泽楠黄文树杨求华邹文政集美大学水产学院福建厦门361021 福建省水产研究所福建厦门361021 鳗鲡现代产业技术教育部工程研究中心福建厦门361021 华中农业大学动物科学技术学院·动物医学院湖北武汉430070

【目的】在仿刺参(Apostichopus japonicus)健康养殖中为了寻找具有良好耐受性、益生性、安全性的益生菌,本研究从仿刺参肠道内容物中分离获得一株植物乳杆菌(Lactobacillus plantarum)HY21,对其益生潜能进行评价。【方法】利用摇瓶发... 详细信息

【目的】在仿刺参(Apostichopus japonicus)健康养殖中为了寻找具有良好耐受性、益生性、安全性的益生菌,本研究从仿刺参肠道内容物中分离获得一株植物乳杆菌(Lactobacillus plantarum)HY21,对其益生潜能进行评价。【方法】利用摇瓶发酵培养、应用环境因子模拟试验、抗生素药敏测试等方法,分析*** HY21的生长特性、产酸性能、发酵液的抗氧化性质和对水产致病菌的抑制作用;检测菌体的疏水性、自聚性和共聚性、黏附力和药物敏感性,以及对应用环境因子的耐受性。【结果】*** HY21摇瓶发酵培养温度30°C、初始pH 8.0,于2–10 h为对数生长期,发酵18 h后pH达到最低3.6;发酵液对溶藻弧菌的抑菌直径达到(13.96±0.30)mm,对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-trinitrophenylhydrazine,DPPH)自由基清除率达到95.45%±1.56%;*** HY21的疏水率为60.42%±2.78%、自聚率为22.69%±1.36%,与溶藻弧菌共聚率为27.98%±1.45%;对体表和肠道黏液蛋白的黏附量分别达到(1.66±0.01)×10^(6)CFU/mL和(1.23±0.15)×10^(6)CFU/mL;对13种常见的抗菌药物均表现敏感;菌体在模拟胃肠液(pH 3.0,pH6.8)中孵育3 h存活率均可达99%以上,在10%鱼胆汁溶液中孵育3 h存活率达到68.11%±7.98%,在3%海盐溶液中孵育16h存活率达到97.58%±7.14%。【结论】*** HY21具有良好的定殖作用、抑菌作用、抗氧化作用等益生特性,而且在应用环境中具有高存活率和高安全性,可以作为一株新的水产益生菌,为开发水产益生菌制剂提供科学理论依据。

关键词：植物乳杆菌耐受性黏附性抑菌作用抗氧化作用

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NUMERICAL ANALYSIS OF MINDliN SHELL BY MESHLESS LOCAL PETROV-GALERKIN METHOD

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Acta Mechanica Solida Sinica 2008年第2期21卷 160-169页

作者： Di li zhongqin li Shuhui li School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China School of Transportation and Vehicle Engineering Shandong University of Technology Zibo 255049 China

The objectives of this study are to employ the meshless local Petrov-Galerkin method （MLPGM） to solve three-dimensional shell problems. The computational accuracy of MLPGM for shell problems is affected by many factors, including the dimension of compact support domain, the dimension of quadrture domain, the number of integral cells and the number of Gauss points. These factors＇ sensitivity analysis is to adopt the Taguchi experimental design technology and point out the dimension of the quadrature domain with the largest influence on the computational accuracy of the present MLPGM for shells and give out the optimum combination of these factors. A few examples are given to verify the reliability and good convergence of MLPGM for shell problems compared to the theoretical or the finite element results.

关键词： meshless methods meshless local Petrov-Galerkin method moving least square shell

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基于ISABO-SVM的冲击地压危险等级预测

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黑龙江科技大学学报 2024年第4期34卷 611-616页

作者：李忠勤刘赵龙黑龙江科技大学电气与控制工程学院哈尔滨150022

为有效提高冲击地压危险等级预测的准确率,建立了基于改进的减法平均算法(ISABO)优化支持向量机(SVM)的冲击地压危险等级预测模型。通过提取声发射信号的上升时间和绝对能量等5个时域特征参数,结合煤岩体抗压强度,构建了冲击地压预测的... 详细信息

为有效提高冲击地压危险等级预测的准确率,建立了基于改进的减法平均算法(ISABO)优化支持向量机(SVM)的冲击地压危险等级预测模型。通过提取声发射信号的上升时间和绝对能量等5个时域特征参数,结合煤岩体抗压强度,构建了冲击地压预测的特征参数数据库;根据特征参数数据库计算每个样本的综合危险指数,将冲击地压危险性划分为四个等级。以特征参数数据库和危险等级为模型输入和输出,通过ISABO优化SVM预测冲击地压危险等级过程中的核参数和惩罚因子。结果表明,与传统SVM模型以及减法平均算法(SABO)优化后的SVM模型相比,建立的ISABO-SVM模型预测准确率提高至98%。

关键词：冲击地压声发射抗压强度减法平均算法支持向量机

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Shrinkage of Mt. Bogda Glaciers of Eastern Tian Shan in Central Asia during 1962–2006

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Journal of Earth Science 2016年第1期27卷 139-150页

作者： Kaiming li zhongqin li Cuiyun Wang Baojuan Huai School of Architecture and Urban Planning Lanzhou City University Cold and Arid Region Environmental and Engineering Research Institute Chinese Academy of Sciences

Many small mountain glaciers have been reported undergoing strong shrinkage, and it is therefore important to understand how they respond to climate change. The availability of topographic maps from 1962, Landsat TM imagery from 1990 and ASTER（Advanced Spaceborne Thermal Emission and Radiometer） imagery from 2006 and field investigation of some glaciers allow a comprehensive analysis of glacier change based on glacier size and topography on Mt. Bogda. Results include：（1） an overall loss of a glacierized area by 31.18±0.31 km^2 or 21.6% from 1962 to 2006,（2） a marked dependence of glacier area shrinkage on initial size, with smaller glaciers experiencing higher shrinkage levels,（3） the disappearance of 12 small glaciers,（4） a striking difference in area loss between the southern and northern slopes of 25% and 17%, respectively. A subset of the investigated glaciers shows that the area 57.45±0.73 km2 in 1962 reduced to 54.79±0.561 km^2 in 1990 and 48.88±0.49 km^2 in 2006, with a relative area reduction of 4.6% during 1962-1990, and 10.8% during 1990-2006. The corresponding volume waste increased from 6.9% to 10.2%. Three reference glaciers were investigated in 1981 and revisited in 2009. Their terminus experienced a marked recession. Meteorological data from stations around Mt. Bogda reveals that glacier shrinkage is correlated with winter warming and an extension of the ablation period. Precipitation on the northwest side of the range shows a marked increase, with a slight increase on the southeast side.

关键词： glacier shrinkage climate change water resources Bogda Mountain Tian Shan.

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Texture Evolution Induced by Deformation in Aluminum Alloy

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上海交通大学学报 2004年第Z2期38卷 206-211页

作者： Zhao Yixi lin zhongqin li shuhui Yu zhongqi School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China School of Mechanical Engineering Shanghai Jiaotong Univ. Shanghai200030 China

The lower formability of aluminum alloy sheets is the inherent characteristic of the material. During material forming processes the material undergoes a complex strain history. In this paper, the effect of crystallographic texture induced by deformation in aluminum sheet is studied. The transformation of crystallographic textures induced by uniaxial tensile, cup drawing and bulge tests was measured through X-ray diffraction and analyzed. The author studied the texture evolution rule under different strain paths. A qualitative relationship between the deformation and texture evolution has been founded.

关键词： texture evolution aluminum alloy deformation strain path

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Chemical Characteristics and Environmental Significance of Fresh Snow Deposition on Urumqi Glacier No.1 of Tianshan Mountains, China

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Chinese Geographical Science 2010年第5期20卷 389-397页

作者： li zhongqin li Huilin DONG Zhiwen ZHANG Mingjun The State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research Institute/Tianshan Glaciological Station Chinese Academy of Sciences Lanzhou 730000 China College of Geography and Environment Science Northwest Normal University Lanzhou 730070 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Ice and snow chemistry of alpine glaciers is crucial for the research of regional atmospheric environment change. Fresh snow samples were weekly collected from Urumqi Glacier No.1 in the Tianshan Mountains, Xin- jiang, China, and the chemical characteristics and seasonal variations of major ions, mineral dust, δ18O and trace metals were measured. Results show that the concentrations of major ions in the snow are Ca2+ > SO42-> NH4+ > NO3-> Cl-> Na+ > Mg2+ > K+, in which Ca2+ is the dominant cation, and SO42-is the dominant anion. All major ions have close positive correlations with each other except NO3-. δ18O shows positive correlation with air temperature change during the study period. Mineral dust particle and major ionic concentrations in fresh snow have obvious seasonal change, with high concentration in spring but low concentration in summer and autumn, which indicates that the chemical mass input from Asian dust activity to snow is very significant. Temporal changes of trace metals in fresh snow, e.g., Cd, Pb, Zn, Al, Fe, have shown that human-induced pollution of central Asian region also has large contribution to the snow chemistry on alpine glaciers of the Tianshan Mountains.

关键词： Urumqi Glacier No. 1 fresh snow snow chemistry Tianshan Mountains

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Region-wide glacier area and mass budgets for the Shaksgam River Basin,Karakoram Mountains,during 2000–2016

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Journal of Arid Land 2021年第2期13卷 175-188页

作者： WANG Panpan li zhongqin XU Chunhai WANG Puyu College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China State Key Laboratory of Cryospheric Sciences/Tianshan Glaciological Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The Karakoram Mountains are well known for their widespread surge-type glaciers and slight glacier mass *** the one hand,glaciers are one of the sensitive indicators of climate change,their area and thickness will adjust with climate *** the other hand,glaciers provide freshwater resources for agricultural irrigation and hydroelectric generation in the downstream areas of the Shaksgam River Basin(SRB)in western *** shrinkage of glaciers caused by climate change can significantly affect the security and sustainable development of regional water *** this study,we analyzed the changes in glacier area from 2000 to 2016 in the SRB using Landsat TM(Thematic Mapper)/ETM+(Enhanced Mapper Plus)/Oli(Operational Land Imager)*** is shown that the SRB contained 472 glaciers,with an area of 1840.3 km2,in *** glacier area decreased by 0.14%/a since 2000,and the shrinkage of glacier in the southeast,east and south directions were the most,while the northeast,north directions were the ***-covered area accounted for 8.0%of the total glacier *** estimated elevation and mass changes using the 1 arc-second SRTM(Shuttle Radar Topography Mission)DEM(Digital Elevation Model)(2000)and the resolution of 8 m HMA(High Mountain Asia)DEM(2016).An average thickness of 0.08(±0.03)m/a,or a slight mass increase of 0.06(±0.02)m w.e./a has been obtained since *** found thinning was significantly lesser on the clean ice than the debris-covered *** addition,the elevation of glacier surface is spatially heterogeneous,showing that the accumulation of mass is dominant in high altitude regions,and the main mass loss is in low altitude regions,excluding the surge-type *** surge-type glaciers,the mass may transfer from the reservoir to the receiving area rapidly when surges,then resulting in an advance of glacier *** main surge mechanism is still unclear,it is worth noting that the surge did not increase the glacier mass in this study.

关键词： glacier mass balance SRTM DEM HMA DEM Karakoram Mountains

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Hydrological processes of glacier and snow melting and runoff in the Urumqi River source region, eastern Tianshan Mountains, China

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Journal of Geographical Sciences 2015年第2期25卷 149-164页

作者： SUN Meiping YAO Xiaojun li zhongqin ZHANG Mingjun College of Geography and Environment Science Northwest Normal University Lanzhou 730070 China State Key Laboratory of Cryosphere Sciences Cold and Arid Region Environment and Engineering Research Institute CAS Lanzhou 730000 China

Hydrological processes were compared, with and without the influence of precipita- tion on discharge, to identify the differences between glacierized and non-glacierized catchments in the Urumqi River source region, on the northern slope of the eastern Tianshan Mountains, during the melting season （May-September） in 2011. The study was based on hydrological data observed at 10-min intervals, meteorological data observed at 15-min intervals, and glacier melting and snow observations from the Empty Cirque, Zongkong, and Urumqi Glacier No.1 gauging stations. The results indicated that the discharge differed markedly among the three gauging stations. The daily discharge was more than the nightly discharge at the Glacier No.1 gauging station, which contrasted with the patterns observed at the Zongkong and Empty Cirque gauging stations. There was a clear daily variation in the discharge at the three gauging stations, with differences in the magnitude and duration of the peak discharge. When precipitation was not considered, the time-lags between the maximum discharge and the highest temperature were 1-3 h, 10-16 h, and 5-11 h at the Glacier No.l, Empty Cirque, and Zongkong gauging stations, respectively. When precipitation was taken into consideration, the corresponding time-lags were 0-1 h, 13 h, and 6-7 h, respectively. Therefore, the duration from the generation of discharge to confluence was the shortest in the glacierized catchment and the longest in the catchment where was mainly covered by snow. It was also shown that the hydrological process from the generation of discharge to confluence shortened when precipitation was considered. The factors influencing changes in the discharge among the three gauging stations were different. For Glacier No.1 station, the discharge was mainly controlled by heat conditions in the glacierized region, and the discharge displayed an accelerated growth when the temperature exceeded 5℃ in the melt season. It was found that the englaci

关键词： glacier and snow melting runoff generation and confluence hydrological process Urumqi Riversource region Tianshan Mountains

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Glacier Volume Calculation from Ice-Thickness Data for Mountain Glaciers—A Case Study of Glacier No. 4 of Sigong River over Mt. Bogda, Eastern Tianshan, Central Asia

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Journal of Earth Science 2014年第2期25卷 371-378页

作者： Puyu Wang zhongqin li Wenbin Wang Huilin li Feiteng Wang State Key Laboratory of Cryospheric Sciences Tianshan Glaciological Station Cold and Arid Region Environment and Engineering Research Institute Chinese Academy of Sciences College of Geography and Environment Science Northwest Normal University

The determination of total glacial volume is important for the observation of climatic change and its consequences such as global sea-level rise. The tongue area of Glacier No. 4 of Sigong River over Mt. Bogda, eastern Tianshan was surveyed by ground-penetrating radar （GPR） and real time kinematic （RTK）-global positioning system （GPS） during the summer campaign 2009. In order to calculate the glacier volume, both co-kriging algorithm and estimation based on the theory of perfectly plastic material were employed. Results indicated that the ice-thickness distribution of the investigated glacier ranges from 0 to 105.0 m, with the mean thickness of 27.6 m in 2009. The corresponding ice volume was -0.076 km3 （-0.068 km3 water equivalent）. The bedrock topography shows more undulating than the glacier surface. The difference of the calculated ice volume in this study and the estimated value from the empirical formula is large. Therefore, it is urgent to validate the applicability of the ex- isting empirical formula.

关键词： ice volume ice-thickness GPR Glacier No. 4 of Sigong River Tianshan.

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