气象通信系统发展与展望   总被引：1，自引：0，他引：1  

李湘 《气象》2010,36(7):56-61

气象通信系统是支撑气象业务和大气科学研究的数据收集和传输平台。在经历了从手工到自动,从点对点的数据传输到网络通信和数据广播的发展后,我国气象通信系统已成为由国际气象通信系统、国内气象通信系统组成,覆盖各级气象部门及部门外相关业务和科研用户,具备全球及国内各类观测资料和预报预测产品收集、分发、交换控制及传输监视能力的数据传输平台。作者回顾了气象通信发展历程,分析了气象通信系统的技术和业务现状,对气象通信的未来发展进行了展望。  相似文献   

Exploitation of gold in an historic sewage sludge stockpile, Werribee, Australia: resource evaluation, chemical extraction and subsequent utilisation sludge     

S. J. Reeves  I. R. Plimer 《Journal of Geochemical Exploration》2001,72(1)

Sewage sludges are potential targets for economic extraction of Au because of the documented Au content of sewage sludges worldwide, which are of the order of some ore deposits currently mined for Au. The sewage of Melbourne, Australia, was stockpiled in large, closed, lagoonal tanks from 1898 until 1980. Reeves, Plimer and Foster, 1999, have conducted, and published, an extensive and exhaustive study of the Werribee sewage reserves utilising RNAA, INAA, GFAAS, ICPMS, and FLAAS to determine 31 elements, including Au, Ag, Sb, As, Cd, Hg, Zn, Cu, and Pb. The study was initiated to determine Au, Ag and other metal variations in both space and time and to investigate the economics of chemical extraction of the precious metals. A total of 149 samples from over 50 hand-auger drillholes to a depth up to 4m were analysed from the stockpiles, with Au assays yielding remarkably consistent results. Average grades of 0.77 g/t Au and 18.8 g/t Ag have been documented for a measured resource of 770,000 m³. Laboratory-based extractive metallurgy of the Werribee sludges has demonstrated that Au, Ag, and Zn can be removed with relative ease by heap-leaching using modified conventional technology, albeit with prohibitive reagent consumption. The extraction of the precious metals also results in the variable removal of contaminant metals such as Cd, As, Sb, Hg and Cr which may render the sludges fit for sale as agricultural fertiliser, provided organic pollutants and pathogenic organisms are below governmental environmental protection limits.  相似文献   

甘肃省畜牧气候资源分析   总被引：2，自引：0，他引：2  

葛秉钧 《干旱气象》1995,(1)

从甘肃省畜牧气候资源基本特点出发，着重分析了畜牧业界限温度指标、时空分布以及气候条件对牧草产量、家畜膘情变化、牧事活动的影响。  相似文献   

Characteristics of trace elements in contaminated rivers and their environmental significance     

Xuyin YUAN Zhiyong SHEN Xu DENG Yun GAO 《中国地球化学学报》2006,25(B08):140-141

Several rivers researched around Taihu Lake in Chinese eastern plain are distributed to the west of the lake. Pollutants of different types from tributaries and inlets flow directly into the main rivers and finally into the lake. They change trace elements of rivers fi＇om which we can analyze. Researches about trace elements are helpful for understanding the pollutant characteristics, industrial structure and agricultural cultivation in the area of network rivers in the plain of China. Samples of water column, suspended matter and sediment were collected fi＇om the west rivers of Taihu Lake, which represent three typical rivers. Observation in the field and the primary composition analysis showed the Caoqiao River was mainly contaminated by industrial wastewater, the Liangxi River was discharged by domestic sewage and the Dapu River was principally input by farmland runoff. REE concentrations and their normalized curves showed obvious characters for rivers discharged by different sewages. The contents of total REE in water column followed the order of the Caoqiao River, the Dapu River and the Liangxi River fi＇om high to low. TREEs in suspended matter and sediments follow the order of the Dapu River 〉 the Caoqiao River 〉 the Liangxi River. REE normalized curves （for Australia shale） suggested that significant diversities were presented in water column, suspended matter and sediments, i.e., heavy REE enrichment in water, middle REE enrichment in suspended matter, and smooth curves for sediments. But the heavy pollution resulted in several anomalous curves in the same rivers. Some element ratios were selected as indices for polluted rivers based on their geochemical properties and diversities between rivers. The results displayed the discriminative indices for water column, suspended matter and sediment. The effective indices were Pb/Fe, Cr/Fe, Ni/Fe, Pb/Ni, Zn/Ni for water column, Cu/Al, Cu/Fe, Zn/Fe, K/Ca, K/Na, Pb/Co, Zn/Co for suspend matter and Pb/Fe, K/Ca, Ca/Mg, Zn/Ni for sediment, respectively. In general, rivers mainly discharged by industrial sewage have high ratios of Pb/Ni, K/Ca, are enriched in the middle REE and have positive Gd anomaly. The domestic sewage flowing into rivers reveals high ratios of Zn/Ni, Pb/Fe, and is enriched in the heavy REE, and has the positive Eu anomaly. If runoff of farmland enters into the rivers, it will have high ratios of Ca/Mg, K/Na, high lanthanum, and show the smooth normalized curves of REE.  相似文献   

九寨沟国内游客特征与前景   总被引：2，自引：1，他引：1  

聂献忠  张捷  哈文  向春元 《山地学报》1998,(1)

通过实际问卷调查分析,揭示了九寨沟国内游客在地域来源、收入、职业等方面的分布规律及基本原因．并根据其客源目标市场特点及不利因素,分别从客源市场及其结构、旅游地形象、可持续发展等方面对其发展前景进行了探讨．  相似文献   

北京地区水资源与产业结构最优化分析   总被引：1，自引：0，他引：1  

李小梅  张卫东 《地学前缘》1996,3(2):249-254

北京地区现有各产业部门的用水结构不甚合理，造成水资源严重浪费，同时也抑制了国内生产总值的增长。本文采用线性规划方法，以１９９４年北京地区开发利用的水资源总量作为水量约束，以各产业部门最大经济效益作为目标，寻求各产业问及其内部的合理用水结构，为协调北京地区水资源与经济的持续发展提供科学依据。  相似文献   

GIS环境下污水管网设计流量的快速计算     

孟令奎  边馥苓  刘玉贤 《武汉大学学报(信息科学版)》1997,(1)

针对ＧＩＳ环境下污水管网设计问题，提出了一种快速计算管段设计流量的方法——递归方法。分析了递归的原理、链式表的建立以及递归算法的具体实现等，并以实例阐述了递归计算的各个步骤  相似文献   

污水泵浓盐水示踪测流研究          下载免费PDF全文

郭建斌  张庆五  吴海波  郭智成 《水科学进展》2003,14(5):643-646

针对污水泵流量监测中常规测流方法的缺点,结合工程实践,研究浓盐水示踪法在污水泵流量监测中的可行性,提出该方法适于在低背景盐浓度下污水的测流;观察激励信号、温度等对测流结果的影响,给出修正方法;利用计算机采集技术,提高方法的准确性、实时性。  相似文献   

δ15N在污水生物脱氮机理研究中的应用     

刘贤荣  闫秀懿  张永祥 《吉林地质》2003,22(1):54-57,82

近年来,硝酸盐氮的污染愈来愈严重.无论是地表水还是地下水都受到不同程度的氮污染.控制氮污染及处理氮污染问题已经提到我国水污染控制的议事日程.本文探索微生物处理含氮污水的过程中反硝化作用的脱氮机理,使用δ15N标识技术研究水体中三氮运移转化过程中的质量不守恒,证明δ15N标识技术研究确定不同形态氮的数量各系是可行的.研究水体中三氮质量不守恒现象,将解决含氮污水生物净化中污泥上浮问题、氮污染含水层生物修复中气阻问题.  相似文献   

城市缓流水体污染成因分析及维护对策   总被引：17，自引：0，他引：17       下载免费PDF全文

朱亮  蔡金榜  陈艳 《水科学进展》2002,13(3):383-388

在讨论城市缓流水体的运移特征、水化学过程及污染源的基础上,提出了建立科学的城市水务管理体制,城市水利工程与生态工程建设相结合,充分发挥水系工程在城市水体环境保护中的作用,以及完善暴雨污水综合治理方法等保护城市缓流水体的对策.  相似文献