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Groundwater regime and calculation of yield response in North China Plain: a case study of Luancheng County in Hebei Province

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Journal of Geographical Sciences 2002年第2期12卷 94-102页

作者： Jia Jin-sheng Yu Jing-jie liu chang-ming Institute of Geographic Sciences and Natural Resources Research CAS Beijing China

The groundwater table has been declining at a rate of 0.65 m/yr in Luancheng County since large scale groundwater extraction carried out in the 1960s. The drop of precipitation, substantial increase in agricultural output, variations of crop planting structure and construction of water conservancy projects in the headwater area all tie up with the decline of the groundwater table. On the basis of analyzing the hydrogeological conditions and the water resources utilization of Luancheng County, a three-dimensional groundwater flow model was developed to simulate the county抯 groundwater flow through finite-difference method using Visual Modflow software. We divide the research field into four parts after analyzing the hydrogeological condition. Based on parameter calibration and adjustment using measured data, the hydraulic conductivity and specific yield were simulated. Using the calibrated model, we analyze the agricultural water saving potentiality and its influence on the groundwater. The results are as follows: (1) if we decrease the amount of water extracted by 0.14×108 m3, the average groundwater table of the five observation wells in December will rise by 0.33 m; (2) if we decrease the water by 0.29×108 m3, the average groundwater table of the five observation wells in December will rise by 0.64 m; and (3) if we increase the water by 0.29×108 m3, the average groundwater table of the five observation wells in December will decline by 0.45 m. So we can draw a conclusion that controlling the agricultural water use is an important way to prevent the decline of groundwater table.

关键词： groundwater table Visual Modflow zonation of the hydrogeological parameters groundwater simulation model groundwater exploitation

Asynchronism-synchronism of regional precipitation in South-to-North Water Transfer planned areas

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Journal of Geographical Sciences 2001年第2期11卷 161-169页

作者： ZHENG Hong-xing, liu chang-ming (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) Institute of Geographic Sciences and Natural Resources Research CAS Beijing China

This paper proposes a method on analyzing the asynchronism-synchronism of precipitation of different hydrological regions regarding the S-to-N water transfer areas of eastern China. The general process of the analysis includes three steps. Firstly, we created the rainfall series of the region concerned by calculating the regional average rainfall of the stations in the area with the help of the classical Thiessen Polygon method. Secondly, the standards of assessment indices for wetness or dryness are set according to Gamma distribution function with a certain probability P 37.5% or 62.5% given respectively. Finally, the frequency of nine combinations are counted as the quantitative feature of asynchronism and synchronism in three time scales, that is the yearly, seasonal and monthly scales. The asynchronism-synchronism of two region pairs has been estimated. The results show that the frequency of precipitation asynchronism in 1957–1998 is larger than the synchronism frequency for both the North China-middle and lower Yangtze River pair and for the North China-upper Hanjiang River pair. As for the synchronism phenomena, the frequency of Nd?Sd is rather low. As the combinations that are suitable for water transfers are Nd?Sw, Nn?Sw, Nd?Sn and Nn?Sn, the total frequency of these combinations for North China-middle and lower Yangtze River is 40% on an annual basis, but only 28% in spring when water shortages are most likely to occur. The total frequency of these combinations for North China-upper Hanjiang River is about 24% on an annual basis, but 35% in spring and winter. It should be noted that if future precipitation patterns are similar to that of the period 1957–1998, it is very important to change the natural character of asynchronism-synchronism by enhancing the capability of hydro-projects regulation and improving management of the water transfer project.

关键词： synchronous frequency asynchronous frequency South-to-North Water Transfer

High Energy Terahertz Parametric Oscillator Based on Surface-Emitted Configuration

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Chinese Physics Letters 2013年第2期30卷 139-142页

作者： XU De-Gang ZHANG Hao JIANG Hao WANG Yu-Ye liu chang-ming YU Hong LI Zhong-Yang SHI Wei YAO Jian-Quan Institute of Laser and Optoelectronics College of Precision Instrument and Optoelectronics EngineeringTianjin UniversityTianjin 300072 Key Laboratory of Optoelectronics Information Science and Technology(Ministry of Education) Tianjin UniversityTianjin 300072 North China University of Water Resources and Electric Power Zhenzhou 450011

We experimentally demonstrate a high power nanosecond pulsed terahertz(THz)-wave parametric oscillator(TPO)by using a wide pump beam.A surface emitted cavity configuration is employed to reduce the THz absorption in MgO:LiNbO_(3) *** THz wave can be tuned from 1 THz to 3 THz.A maximum THz output energy of 438 nJ/pulse is achieved at 1.56 Hz using a 4.5-mm-diameter pump beam with a pulse energy of 226 mJ pump energy with the repetition of 10 Hz,corresponding to the energy conversion efficiency of 1.94×10^(-6).

关键词： pump Configuration repetition

Assessment and utilization of soil water resources

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Journal of Geographical Sciences 2001年第1期11卷 87-91页

作者： WANG Hui-xiao, liu chang-ming, YANG Zhi-feng (State Key Laboratory of Water Environment Simulation, Beijing Normal University, Beijing 100875, China) State Key Laboratory of Water Environment Simulation Beijing Normal University Beijing China

Based on the analyses of water interactions and water balance, this paper discusses the issues on the assessment and regulation of soil water resources, which lays the scientific basis for limited irrigation and water... 详细信息

关键词： soil water resources assessment water interactions water balance

Coupling of water and land resources and its application in regionalization

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Journal of Environmental Sciences 1999年第1期11卷 17-21页

作者： Chen Jian yao, liu chang ming Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China E mail: chenjy@***

This paper focuses on the coupling of water and land resources based on several factors related closely to either water or land resources, which have become a topical subject due to the economic expansion and their sustainable development in recent years. A case of Qihe County in Shangdong Province, China has been used to demonstrate the methodology of the coupling and its application in regionalization with the help of geographical information system (GIS) tool. Field observation and measurement of soil salt and moisture in several profiles are used to verify the results of the coupling, which gives reasonable distribution of different areas regarding to the advantages and disadvantages for sustainable agriculture.

关键词： coupling water resource land resource regionalization.

In vitro and in vivo evaluation of a novel oral insulin formulation

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Acta Pharmacologica Sinica 2006年第10期27卷 1382-1388页

作者： Er-li MA Hong MA Zheng liu chang-xue ZHENG ming-xing DUAN~2 State Key Laboratory of Bio-membrane and Biotechnology,Department of Biological Sciences and Biotechnology,Tsinghua University Beijing 100084,China Department of Biological Sciences and Biotechnology State Key Laboratory of Bio-membrane and Biotechnology Tsinghua University Beijing China

Aim:To develop a stable self-emulsifying formulation for oral delivery of ***:Caco-2 cell line and diabetic beagles were used as in vitro and in vivomodels to study the absorption mechanism and the hypoglycemic efficacy of *** addition,various physicochemical parameters of the formulationsuch as droplet size,insulin encapsulation efficiency and stability were ***:This formulation enabled changes in barrier properties of Caco-2monolayers,as referred by transepithelial electrical resistance(TEER)and appar-ent permeability coefficients(Papp)of the paracellular marker ranitidine(20-foldgreater than control)but not transcellular marker propranolol,suggesting that theopening of tight junctions was *** diabetic beagle dogs,the bioavailabilityof this formulation was up to 15.2% at a dose of 2.5 IU/kg in comparison with thehypoglycemic effect of native insulin(0.5 IU/kg)delivered by ***:This formulation,recently approved by the China StateFood and Drug Administration to enter clinical trials,was stable,degradation-protected and absorption-enhanced,and provided a promising formulation fororal insulin delivery.

关键词： insulin oral delivery Caco-2 diabetic beagles

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水资源及其内涵的研究现状和时间维的探讨

水科学进展 2000年第2期11卷 153-158页

作者：成立刘昌明中国科学院地理研究所北京100101

随着当今世界所涌出的新理论、新问题 ,概述了水资源研究出现的若干新形势。换一角度 ,从时间对水资源研究的作用上重新探讨了水资源的涵义。

关键词：水资源地表水利用地下水利用水文更新时间

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流域水资源实时调控方法和模型研究

水利学报 2006年第9期37卷 1122-1128页

作者：王煜黄强刘昌明黄河勘测规划设计有限公司河南郑州450003 西安理工大学水利水电学院陕西西安710048 中科院地理科学与资源研究所北京100101

本文采用控制论和临界调控理论,提出流域水资源实时多维临界调控的概念和方法。以黄河下游为例,通过对水资源实时调控过程和不同调控结构的特征分析,建立了黄河小浪底以下河段枯水实时调度模型,并提出了求解方法。该模型以水库调度、河... 详细信息

本文采用控制论和临界调控理论,提出流域水资源实时多维临界调控的概念和方法。以黄河下游为例,通过对水资源实时调控过程和不同调控结构的特征分析,建立了黄河小浪底以下河段枯水实时调度模型,并提出了求解方法。该模型以水库调度、河段配水和流量预警控制相结合的调控方式,采用多时间步长嵌套和滚动修正,实现黄河下游水资源实时调控。应用结果表明,该模型技术可靠,具有可操作性。

关键词：流域水资源实时调控模型

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社会形态与发展模式的耦合

烟台大学学报（哲学社会科学版） 2010年第3期23卷 13-19页

作者：刘长明山东经济学院和谐发展研究中心山东济南250014

所谓社会形态,指的是一定的社会经济、政治、文化、人与自然的关系等合成的社会结构类型;而发展模式,是发展理念、发展手段、发展路径、发展目的的集成。和谐发展理论视野下的和谐度,是用来量度评价对象和谐与否及和谐指数的数量界限。... 详细信息

所谓社会形态,指的是一定的社会经济、政治、文化、人与自然的关系等合成的社会结构类型;而发展模式,是发展理念、发展手段、发展路径、发展目的的集成。和谐发展理论视野下的和谐度,是用来量度评价对象和谐与否及和谐指数的数量界限。依据和谐度标准,可以将社会形态划分为和谐社会、失衡社会和不确定社会;将发展模式划分为和谐发展、畸形发展和模糊发展。以和谐度划分的社会形态和发展模式具有某种程度的耦合:一般说来,有什么样的社会形态,就有什么样的发展模式做支持系统;而特定的发展模式,则又会催生与其相适应的社会形态。只有大力提升和谐度,才能使畸形发展和模糊发展梯级升华到和谐发展,从而为社会形态由失衡社会和不确定社会过渡到和谐社会提供强有力的发展模式支持。

关键词：社会形态发展模式和谐发展和谐社会耦合