对渭北地区集雨灌溉的思考——以富平县底店乡“窖灌农业”示范区为例

合理高效地利用雨水资源对西北干旱半干旱地区尤其是地表水缺乏地下水不易利用地区的经济发展具有十分重要的意义。基于此 ,我们在陕西省“窖灌农业”试验示范基地对蓄水设施的修筑、运行、维护及水质、雨水利用现状等进行了调研和考察 ,指出了其存在的问题、解决措施及进一步发展的思路 ,为该地及整个渭北地区雨水集流灌溉的进一步发展提供指导和参考

不同时间尺度径流对植被变化的响应

植被覆盖对陆地生态系统的水分循环起着重要作用。径流对植被变化在不同时间尺度的响应研究,对区域生态环境建设及水资源管理具有重要的参考价值。该文介绍基于对比流域法,在多年平均、年际、季节等不同时间尺度径流对植被变化响应的研究结果。多年平均尺度上,由植被类型更替引起的径流绝对变化量,湿润区较干旱区大,其相对变化量在干旱区严重;年际尺度上,因植被变化,径流从一种平衡状态到另一种平衡状态的响应时间因抚育措施和地区不同而不同,造林情况下,湿润地区一般需要15~20 a,干旱地区约需25 a甚至更长,森林自然恢复情况下则需要上百年;季节尺度上,径流对植被变化的响应在季风影响区较四季湿润地区强烈。流量历时曲线研究表明,干旱地区造林,其基流无论在量或发生概率的变化上均较湿润区强烈。

黄土高原典型地区土壤侵蚀共性与特点

通过对黄土高原典型地区土壤侵蚀以往的研究结论进行综合分析 ,在比较土壤侵蚀相似性和差异性的基础上 ,对这些典型地区土壤侵蚀的共性与特点进行了研究 ,结果表明 :1、黄土高原典型地区土壤侵蚀影响因素有降雨、地形及土地利用 ;2、黄土高原各典型地区主要侵蚀类型为水蚀及重力侵蚀 ;主要侵蚀发生时间为汛期 ;主要侵蚀空间分布特征为具有垂直分带性 ;3、绥德地区侵蚀产沙强烈 ,天水地区侵蚀相对轻微 ,安塞地区各种侵蚀特征典型 ,西峰地区土壤侵蚀特殊。

基于GIS的区域水土流失评价研究

以黄土高原为研究区，对该区的水土流失进行系统、宏观、综合的分析，确定了一套适于该区水土流失宏观定量评价的指标体系，并运用ＧＩＳ技术，对该区影响水土流失的各个因素进行空间分析，实现了多源数据的空间集成和专题信息的提取，建立了适于该区水土流失评价的宏观定量数学模型，并对研究区一定评价年限内的水土流失状况进行了应用评价。

Facile preparation of macroscopic soft colloidal crystals with fiber symmetry

A facile, efficient way to fabricate macroscopic soft colloidal crystals with fiber symmetry by drying a latex dispersion in a tube is presented. A transparent, stable colloidal crystal was obtained from a 25 wt % latex dispersion by complete water evaporation for 4 days. The centimeter-long sample was investigated by means of synchrotron small-angle X-ray diffraction (SAXD). Analysis of a large number of distinct Bragg peaks reveals that uniaxially oriented colloidal crystals with face-centered cubic lattice structure were formed.

Photoinduced DNA Cleavage by alpha-, beta-, and gamma-Cyclodextrin-Bicapped C-60 Supramolecular Complexes

Water-soluble supramolecular inclusion complexes of alpha-, beta-, and gamma-cyclodextrin-bicapped C-60 (CD/C-60) have been investigated for their photoinduced DNA cleavage activities, with the aim to assess the potential health risks of this class of compounds and to understand the effect of host cyclodextrins having different cavity dimensions. Factors such as incubation temperature, irradiation time, and concentration of NADH or CDs/C-60 supramolecular inclusion complexes have been examined. The results show that alpha-, beta-, and gamma-CDs/C-60 are all able to cleave double-stranded DNA under visible light irradiation in the presence of NADH. However, a difference in the photoinduced DNA cleavage efficiency is observed, where the cleavage efficiency increases in the order of alpha-, beta-, and gamma-CD/C-60. The difference is attributed to the different aggregation behavior of the inclusion complexes in aqueous solution, which is correlated to the cavity dimension of the host cyclodextrin molecules.

过程系统管理与技术的综合集成

在激烈的市场竞争中，过程企业不仅要重视技术、更要加强管理，实现全局优化运行。提高过程企业的市场竞争能力必须全面综合集成人、组织、战略管理、经营管理、过程管理及信息自动化技术等因素。本文以石化企业为背景，对过程企业面临的问题及发展趋势进行了分析，并且对过程企业管理模式、过程企业的体系结构以及过程集成与优化技术进行了探讨。

基于盆地地下水模型与山区地表水模型耦合的济源盆地地下水模拟研究

The aim of this study is to increase the precision of groundwater modeling. The way is use the distributed model calculate the mountain basin groundwater lateral discharge and the river runoff. With appropriate technique help, the groundwater model can couple the distributed model results. This paper’s study object is makeing the distributed hydrological model HEC-HMS coupled to the popular groundwater model Visual MODFLOW. The application example is Jiyuan basin which is a typical basin of North China. HEC-HMS can calculate the surface runoff and subsurface runoff at mountain-pass. The subsurface runoff can turn to recharge well straightly. The water level - runoff course and Trial method is used to back analyze the parameters of surface runoff to Visual MODFLOW. So the distributed hydrological model can coupled to the groundwater model. The research proved that base on couple the distributed surface water model the groundwater model’s results are notability improved. The example is Jiyuan basin where use the distributed model coupled to the groundwater model. On the base of the coupled model applied to Jiyuan basin groundwater modeling. The paper estimates the groundwater change in the study area. Then, by use the water resources integrated planning results, the article calculate the basin groundwater can be development and utilization quantity and potential.