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Energy Balance-Based SWAT Model to Simulate the Mountain Snowmelt and Runoff——Taking the Application in Juntanghu Watershed(China) as an Example

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Journal of Mountain Science 2015年第2期12卷 368-381页

作者： MENG Xian-Yong YU Dan-Lin liu zhi-hui School of Resources and Environment Science Xinjiang University Key Laboratory of Oasis Ecology Ministry of Education Xinjiang University Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Department of Earth & Environmental Studies Montclair State University Institute of Arid Ecology and Environment Xinjiang University

In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT) model. The model was tested at the Juntanghu watershed on the northern slope of the Tian Shan Mountains, Xinjiang,China. We compared the performances of temperature-index method and energy balanced method in SWAT model by taking Juntanghu river basin as an application example(as the simulation experiment was conducted in Juntanghu River, we call the energy balanced method as SWAT-JTH). The results suggest that the SWAT snowmelt model had overall Nash-Sutcliffe efficiency(NSE) coefficients ranging from 0.61 to 0.85 while the physical based approach had NSE coefficients ranging from 0.58 to0.69. Overall, on monthly scale, the SWAT model provides better results than that from the SWAT-JTH model. However, results generated from both methods seem to be fairly close at a daily scale. Thestructure of the temperature-index method is simple and produces reasonable simulation results if the parameters are well within empirical ranges. Although the data requirement for the energy balance method in current observation is difficult to meet and the existence of uncertainty is associated with the experimental approaches of physical processes, the SWAT-JTH model still produced a reasonably high NSE. We conclude that using temperature-index methods to simulate the snowmelt process is sufficient, but the energy balance-based model is still a good choice to simulate extreme weather conditions especially when the required data input for the model is acquired.

关键词： SWAT Snowmelt model The physical process Energy balance Temperature-index Water balance

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Effect of Climate Variability and Human Activities on Runoff in the Jinghe River Basin, Northwest China

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Journal of Mountain Science 2015年第2期12卷 358-367页

作者： YAO Jun-qiang ZHAO Qiu-dong liu zhi-hui School of Resources and Environment Science Key Laboratory of Oasis Ecology of Ministry of Education Xinjiang University Xinjiang Climate Center Xinjiang Meteorological Administration Institute of Desert Meteorology China Meteorological Administration Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Institute of Arid Ecology and Environment Xinjiang University

Much attention has recently been focused on the effects of climate variability and human activities on the runoff. In this study, we analyzed 56-yr(1957–2012) runoff change and patterns in the Jinghe River Basin(JRB) in the arid region of northwest China. The nonparametric Mann–Kendall test and the precipitation-runoff double cumulative curve(PRDCC) were used to identify change trend and abrupt change points in the annual runoff. It was found that the runoff in the JRB has periodically fluctuated in the past 56 yr. Abrupt change point in annual runoff was identified in the JRB, which occurred in the years around 1964 and 1996 dividing the long-term hydrologic series into a natural period(1957 – 1964) and a climate and man-induced period(1965 – 1996 and 1997 – 2012). In the 1965 – 1996 period, human activities were the main factor that decreased runoff with contribution of 88.9%, while climate variability only accounted for 11.1%. However,the impact of climate variability has been increased from 11.1% to 47.5% during 1997 – 2012, showing that runoff in JRB is more sensitive to climate variability during global warming. This study distinguishes theeffect of climate variability from human activities on runoff, which can do duty for a reference for regional water resources assessment and management.

关键词： Water resource Runoff Climate variability Precipitation Jinghe River Basin

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An observational study on vertical raindrop size distributions during stratiform rain in a semiarid plateau climate zone

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Atmospheric and Oceanic Science Letters 2016年第3期9卷 178-184页

作者： CHEN Yong AN Jun-Ling liu hui-zhi DUAN Jing State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamenChina Key Laboratory for Cloud Physics Chinese Academy of Meteorological SciencesBeijingChina

Vertical raindrop size distributions of two stratiform rain events were measured with a Micro Rain Radar during summer 2009 at a semiarid continental site located in Xilinhot, China （43°38′N, 116°42′E）. The sequential intensity filtering technique （SIFT） was used to minimize the effect of the spurious variability on disdrometric data to obtain the reflectivity-rain rate （Z-R） relationship （Z = αRb）. Compared with the least squares regression （LSR） method, SIFT led to a -5% to 4% change in the coefficient （a） and an 8%-1 5% increase in the exponent （b） of the Z-R relationship at 300 m. Rainfall estimation using the Z-R relationship with SIFT had lower standard deviation than that with LSR. The vertical variability of the mean rain rate, total raindrop numbers, and parameters （a and b） of the Z-R relationship was small below a melting layer, suggesting that using the radar reflectivity of weather radar to estimate stratiform rainfall is relatively accurate, at least in the Xilinhot area.

关键词： Stratiform rain vertical dropsize distributions semiaridclimate Micro Rain Radar

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Design, Synthesis and Antitumor Activity in vitro of a Series of 3-Arylcoumarins

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Chemical Research in Chinese Universities 2013年第6期29卷 1125-1128页

作者： liu zhi-hui LI De-jun JIANG Dan XIAO Chuan SONG zhi-guang JIN Ying-hua Department of Prosthodontics School of StomatologyJilin University Changchun 130021 P.R.China Department of Organic Chemistry College of Chemistry Jilin University Changchun 130021 P.R.China Key Laboratory for Molecular Enzymology and Engineering Ministry of EducationJilin University Changchun 130012 P.R.China

A new series of 7-substituted 3-arylcoumarins was designed, synthesized and evaluated as novel antitumor agents in vitro. It was found that several compounds of them exhibit activity in vitro against SK-HEP-l（hepatocellular carcinoma）, HepG2（hepatocellular carcinoma） and SGC7901（gastric carcinoma） cell lines to some extent. Moreover, compounds 5a, 5b, 6a and 6b have better activity against HeLa（cervical carcinoma） cell and their half maximal inhibitory concentration（IC50） values are less than 10μmol/L.

关键词： 3-Arylcoumarin Antitumor activity Structure modification

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Roll Vortices in the Boundary Layer Caused by a Concave Wind Profile: A Theoretical Study

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Atmospheric and Oceanic Science Letters 2010年第6期3卷 308-311页

作者： liu hui-zhi SANG Jian-Guo State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry （LAPC） Institute of Atmospherie Physics Chinese Academy of Sciences Beijing 100029 China Physies School Peking University Beijing 100871 China

The present study solves a two-layer atmospheric wave equation model with a lower atmosphere concave wind profile and cold-air outbreak over sea, while simultaneously proving that such a wind shear may cause neutral boundary layer roll vortices in the presence of disturbing sources upstream. Without thermal effects, the wind shear-induced waves have band structures at the top of the boundary layer that are similar to cloud street patterns observed over sea. This study proves that dynamic and thermal effects can act independently to initiate the roll vortices in the lower atmosphere. At the same time, a quantitative comparison shows that dynamic effects play a large role in the formation of roll vortices in the initial stage of cold-air outbreak and will be surpassed by thermal effects soon after surface heating commences.

关键词： roll vortex concave wind profile Ekman laver wind shear cold advection

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Design and analysis of logarithmic spiral type sprag one-way clutch

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Journal of Central South University 2015年第12期22卷 4597-4607页

作者：刘志辉严宏志曹煜明 State Key Laboratory of High-performance and Complex Manufacturing(Central South University) School of Mechanical and Electrical Engineering Central South University Department of Mechanical and Energy Engineering Shaoyang University

A complete mathematical model for logarithmic spiral type sprag one-way clutch design and analysis is *** assumes that the motion of all clutch components can be expressed by a model of epicyclic *** takes advantage of Hunt-Crossley contact impact theory to calculate the contact forces between sprags and races,and it can be used for optimization of design and comparison with other types of sprag clutches.A good deal of analysis shows that the parameters of the steady windup angle,the steady contact force,the natural frequency and natural cycle of clutch have nothing to do with the initial velocity of outer race,while the parameters of the maximum transient windup angle,the maximum transient impact force and the steady engagement time increase linearly in the mode of engaging operation of *** is also shown that the strut angle has great influence on the dynamic engagement performance of *** parameters of the steady windup angle,the maximum transient windup angle,the steady engaging time,the steady contact force,the maximum transient impact force and the natural cycle of clutch decrease linearly nearly with the inner strut angle,while the natural frequency of the system increases linearly with the inner strut angle.

关键词： mathematical model logarithmic spiral one-way clutch hunt-crossley windup angle steady contact force transient impact force

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Characteristics of Momentum and Heat Transfer over Semiarid Grasslands with Different Grazing Intensities in Inner Mongolia,China

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Atmospheric and Oceanic Science Letters 2011年第5期4卷 264-269页

作者： WANG Lei liu hui-zhi Bettina KETZER FENG Jian-Wu Christian BERNHOFER State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospherie Physics Chinese Academy of Sciences Beijing 100029 China Institute of Hydrology and Meteorology Chair of Meteorology Technische Universitgit Dresden Tharandt 01737 Germany

The drag coefficient （Ca） and heat transfer coefficient （Ch） with the bulk transfer scheme are usually used to calculate the momentum and heat fluxes in meteorological models. The aerodynamic roughness length （z0m） and thermal roughness length （z0h） are two crucial parameters for bulk transfer equations. To improve the meteorological models, the seasonal and interannual variations of Z0m, Z0h, coefficient kB-1, Cd, and Ch were investigated based on eddy covariance data over different grazed semiarid grasslands of Inner Mongolia during the growing seasons （May to September） from 2005 to 2008. For an ungrazed Leymus chinensis grassland （ungrazed since 1979）, Z0m and z0h had significant seasonal and in- terannual variations. Zorn was affected by the amount and distribution of rainfall, kB 1 exhibited a relatively negative variation compared with z0h, which indicates that the seasonal variation of z0h cannot be described by kB 1. To parameterize Zorn and z0h, the linear regressions between ln（z0m）, ln（z0h）, and the leaf area index （LAI） were performed with R2=0.71 and 0.83. The monthly average kB-1 was found to decrease linearly with LAI. The four-year averaged values of Ca and Ch were 4.5 × 10^-3 and 3.9× 10^-3, respectively. The monthly average Cd only varied by 8% while the variation of Ch was 18%, which reflects the dif- ferent impacts of dead vegetation on momentum and heat transfer at this natural grassland. Moreover, with the removal of vegetation cover, grazing intensities reduced Z0m, Z0h, Cd, and Ch.

关键词： surface roughness length bulk transfer coefficient grazing intensity semiarid grassland

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卵巢癌CD90^+肿瘤干细胞的生物学特性

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中国组织工程研究 2016年第10期20卷 1468-1473页

作者：刘智慧向志辉武汉市妇女儿童医疗保健中心湖北省武汉市430016 华中科技大学同济医学院附属武汉市中心医院湖北省武汉市430000

背景:卵巢癌干细胞学说认为:肿瘤中有一小部分具备自我更新、多向分化的干细胞,属于卵巢癌复发和耐药的根源。相关研究结果显示:CD90能够作为间充质干细胞和其他癌症的干细胞标志物。目的:探讨卵巢癌CD90^+肿瘤细胞的生物学特性。方法:... 详细信息

背景:卵巢癌干细胞学说认为:肿瘤中有一小部分具备自我更新、多向分化的干细胞,属于卵巢癌复发和耐药的根源。相关研究结果显示:CD90能够作为间充质干细胞和其他癌症的干细胞标志物。目的:探讨卵巢癌CD90^+肿瘤细胞的生物学特性。方法:从卵巢癌患者腹水中分离原代卵巢癌细胞,以流式分选法得到CD90^+、CD90^-细胞,采用RT-PCR法检测干细胞相关基因及上皮间质化相关基因表达,采用Transwell小室侵袭实验观察细胞侵袭力,克隆形成实验观察细胞增殖分化能力,悬浮成球实验观察干细胞潜能,动物体内成瘤实验观察成瘤率。结果与结论:(1)原代卵巢癌CD90^+细胞的干细胞相关基因CD44、CD133、ALDH1表达以及EMT相关基因N-cad、Vimentine表达明显高于CD90^-细胞(P<0.05),EMT相关基因E-cad表达低于CD90^-细胞(P<0.05)。(2)随着接种细胞数目的增加,CD90^+、CD90^-细胞的成瘤率升高,CD90^+细胞升高更明显。(3)CD90^+细胞穿膜细胞数、细胞克隆数以及悬浮成球数目显著高于CD90^-细胞(P<0.05)。(4)结果提示CD90^+细胞高表达间质属性基因和干细胞相关基因,具备更高的侵袭力、增殖分化能力、体内成瘤能力和干细胞潜能,CD90^+细胞分离可能成为卵巢癌干细胞分离的新方法。

关键词：干细胞肿瘤干细胞卵巢癌原代细胞 CD90^+细胞生物学特性

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天山北坡融雪期雪层含水率地物光谱特征研究

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光谱学与光谱分析 2013年第8期33卷 2177-2181页

作者：张波刘志辉徐倩新疆大学资源与环境科学学院新疆乌鲁木齐830046 新疆大学教育部绿洲生态重点实验室新疆乌鲁木齐830046 新疆大学干旱生态环境研究所新疆乌鲁木齐830046 干旱半干旱区可持续发展国际研究中心新疆乌鲁木齐830046

积雪含水率是雪层中液态水的含量,也是积雪出流、产流的关键指标,对积雪含水率的研究对春季融雪产流及融雪型洪水有现实意义。借助美国ASD地物光谱仪和Snow Folk积雪特性仪获取原始数据,并利用SPSS19.0和Excel等统计软件对数据进行分析... 详细信息

积雪含水率是雪层中液态水的含量,也是积雪出流、产流的关键指标,对积雪含水率的研究对春季融雪产流及融雪型洪水有现实意义。借助美国ASD地物光谱仪和Snow Folk积雪特性仪获取原始数据,并利用SPSS19.0和Excel等统计软件对数据进行分析、处理,并利用这些数据进行制图、数据综合,建立雪表层的地物光谱特征预测模型。结果表明:积雪的光谱特征曲线由于在可见光和近红外由于吸收呈现出若干波谷;地物光谱特征与积雪表层含水率存在负相关关系,且随着波长的增加这种负相关关系变化明显,并在可见光和近红外形成三个相关关系的极小值;构建雪层含水率的地物光谱反射率模型,可见光范围内,在350nm时的模型精度较高,能够达到75.9%,预测值和实测值拟合程度高,在近红外波段内,1 204nm建模的模拟精度最高。

关键词：天山北坡雪层含水率光谱特征预测模型

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情报学发展目标及其实现策略

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情报科学 2006年第6期24卷 801-805页

作者：刘植惠西南信息公司重庆400013

本文提出了情报学三大发展目标,即:建立数据—信息—知识—情报—智能转换与统一理论;研制情报检索—情报分析—情报服务大集成系统;开发信息、知识、情报的测度方法,同时指出了实现情报学三大发展目标的方略。

关键词：情报学信息知识情报智能

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