Er(ClO_4)_3在DMF中无限稀释摩尔电导率的测定     

王卫东  胡珍珠 《嘉应学院学报》2004,22(6):29-32

在293K～313K温度范围内测定了Er(ClO4)3在DMF溶剂中的电导率,根据λ=(K液-K剂)×10-3/c公式求得Er(ClO4)3的摩尔电导率λ值,应用Kohlraush经验规则:λ=λ0(1-βc),使用Origin软件进行线性拟合,作图外推求得Er(ClO4)3在DMF溶剂中的无限稀释摩尔电导率λ0值,讨论了Er(ClO4)3在DMF溶剂中的无限稀释摩尔电导率与温度的关系  相似文献   

认真做好“水”的文章——实施西部大开发战略的思考     

韦修仁 《南宁师范高等专科学校学报》2001,18(2):1-3

本文比较系统地论述了水资源在西部大开发的重要作用 ,指出必须从更新观念、搞好水利规划、加快发展水利经济、改革水利管理体制、在水利工程建设中引入竞争机制、扩大对内对外开放和依法治水等六个方面有计划、有步骤地推动水利事业的新发展  相似文献   

浅论严羽《沧浪诗话》的理论体系     

来玉英 《南平师专学报》2006,25(3):74-75,81

严羽在《沧浪诗话.诗辨》中提出的诗歌审美特征和诗歌创作的思维方式等理论,形成了严羽美学思想的三大理论体系。即以“妙悟”说为审美主体论、以“兴趣”说为审美特征论和以“入神”说为审美理想论,至今在诗歌创作中仍具有重要的现实意义。  相似文献   

城乡区域统筹供水的经济分析及机制创新     

胡振华 《温州大学学报(社会科学版)》2005,18(1):28-35

该认为城乡区域统筹供水是解决水资源供需矛盾的有效方法，是推进全面建设小康社会的重要方面。城乡区域统筹供水必须发挥政府的公共服务职能，建立政府主导型的市场推动模式，形成政府调控市场，市场调控供求的新机制。  相似文献   

重水与细胞增殖     

郑宇 《闽江学院学报》2002,23(6):81-82

自然界中广泛存在的重水具有抑制细胞增殖的作用,其作用途径表现在对DNA合成的阻滞,对细胞产生“冻结效应“及延长细胞增殖停滞期等方面.抑制程度依细胞种类及分化程度不同而不同.进一步研究重水抑制作用的细胞动力学基础,对重水毒理及生态效应研究有重要意义.  相似文献   

一维纳米线的热学性质     

邢进华 《常熟理工学院学报》2003,17(2):28-30

根据边界条件中声子散射的不同情况，用Boltzmann方程研究了计算一维纳米材料－线的晶格热导率，结果发现，与体热导率相比， 线的热导率显著减小。  相似文献   

Water quality forecast through application of BP neural network at Yuqiao reservoir   总被引：2，自引：0，他引：2  

ZHAO Ying NAN Jun CUI Fu-yi GUO Liang 《浙江大学学报(A卷英文版)》2007,8(9):1482-1487

This paper deals with the study of a water quality forecast model through application of BP neural network technique and GUI (Graphical User Interfaces) function of MATLAB at Yuqiao reservoir in Tianjin. To overcome the shortcomings of traditional BP algorithm as being slow to converge and easy to reach extreme minimum value,the model adopts LM (Leven-berg-Marquardt) algorithm to achieve a higher speed and a lower error rate. When factors affecting the study object are identified,the reservoir's 2005 measured values are used as sample data to test the model. The number of neurons and the type of transfer functions in the hidden layer of the neural network are changed from time to time to achieve the best forecast results. Through simulation testing the model shows high efficiency in forecasting the water quality of the reservoir.  相似文献   

Natural water purification and water management by artificial groundwater recharge     

Balke KD  Zhu Y 《Journal of Zhejiang University. Science. B》2008,9(3):221-226

Worldwide, several regions suffer from water scarcity and contamination. The infiltration and subsurface storage of rain and fiver water can reduce water stress. Artificial groundwater recharge, possibly combined with bank filtration, plant puri- fication and/or the use of subsurface dams and artificial aquifers, is especially advantageous in areas where layers of gravel and sand exist below the earth's surface. Artificial infiltration of surface water into the uppermost aquifer has qualitative and quanti-tative advantages. The contamination of infiltrated fiver water will be reduced by natural attenuation. Clay minerals, iron hy-droxide and humic matter as well as microorganisms located in the subsurface have high decontamination capacities. By this, a final water treatment, if necessary, becomes much easier and cheaper. The quantitative effect concerns the seasonally changing fiver discharge that influences the possibility of water extraction for drinking water purposes. Such changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the fiver discharge and the water need. This method enables a continuous water supply over the whole year. Generally, artificially recharged groundwater is better protected against pollution than surface water, and the delimitation of water protection zones makes it even more save.  相似文献   

都匀市螺丝壳水源林保护区现存珍稀濒危植物鹅掌楸天然分布   总被引：3，自引：1，他引：3  

郭治友 《黔南民族师范学院学报》2003,23(3):34-36

报道分布于都匀市螺丝壳水源林自然保护区鹅掌楸[Liriodendron (Hemsl.)Sarg.]珍稀濒危植物，并就该物种的生物形态特征、居群(Populstion)分布现状、地理分布以及科学研究与资源开发价值进行讨论。  相似文献   

电导法测定HCI在水和甘露醇混合溶剂中的活度系数     

杨秋玲  朱敏 《临沂师范学院学报》2007,29(3):42-44

应用电导法测定了HCl在水和甘露醇混合溶剂中的活度系数，讨论了电解质溶液活度系数与温度和浓度的关系．  相似文献