共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
常熟市因城镇化快速发展导致中心城区水生态环境恶化,部分河道黑臭现象严重,经过3年的综合治理,常熟市成功实现了消除城区黑臭水体的目标.本文以曹家湾河、山湖苑河为典型案例,从中心城区水质现状、水体黑臭成因、工程整治措施等多个方面,具体阐述了常熟市在黑臭水体治理方面的整治措施和治理成效,可为其他类似城市和地区的黑臭河道治理提... 相似文献
3.
4.
农村黑臭水体的存在一直阻碍着农村经济发展以及农村居民生活质量的提升.通过实地调研与问卷调查相结合的方式,对河南省农村84个水体进行信息采集,参考了黑臭程度,水体面积,水体污染类型等指标.结果显示所调研水体内轻度黑臭53.57%、中度黑臭27.38%,重度黑臭19.05%,整体呈现轻至中度黑臭;分析5种污染类型地区占比和... 相似文献
5.
河道生态修复技术及其在上海市的实践 总被引:2,自引:0,他引:2
为进一步改善中心城区黑臭河道水质,基本消除中心城区河道黑臭,2005年,上海市水务局开展了中心城区黑臭河道深化治理工程,到目前为止,已有45条河道进行了深化治理.在大量的黑臭河道深化治理实践的基础上,根据现有资料,选取了26条(段)典型河道作为本次生态修复技术研究的样本,通过对这些河道黑臭原因进行分析,并对其治理过程中采用的关键技术进行总结,旨在为今后上海地区黑臭河道生态修复提供参考. 相似文献
6.
《中国农村水利水电》2018,(12)
以盐城市蔷薇河为研究对象,基于因子分析法和优化的非线性灰色伯努利模型,结合2009-2017年的水质数据,分析黑臭水体综合整治工程对河道水质改善和主要污染因子的治理效果。结果证明实施黑臭水体综合整治工程后,蔷薇河水质得到明显提升,生活污染以及营养元素污染治理效果明显,但无机污染和水体物理环境状况改善效果不明显,需要进一步加强相应措施的制定和实施,为规划下一阶段黑臭水体整治工程的工作目标及任务提供了参考和依据。 相似文献
7.
易春权 《国际沙棘研究与开发》2017,(4)
随着经济的快速发展和城市化进程的加快,我国许多城市河流水质污染和生态退化问题十分突出,耗氧性有机污染物和氮磷营养盐含量居高不下,甚至出现了季节性和常年性水体黑臭现象.因此,解决城市河流的污染、恢复河流的生态和社会功能问题仍然是城市可持续发展过程中急需解决的关键任务之一.本文结合本公司治理黑臭河道的相关经验,从工程治理措施以及长效管理两个方面展开探讨. 相似文献
8.
城市黑臭水对公共安全和社会环境有很大影响。城市黑臭水的形成有许多复杂的综合性的原因,文章对黑臭水体的形成原因及其原理进行概述。 相似文献
9.
10.
李亮 《国际沙棘研究与开发》2017,(6)
村镇生活污水的无序排放是村镇水环境污染的原因之一,是造成黑臭水体的重要因素,村镇生活污水的治理十分紧迫.本文分析了村镇生活污水的主要特点和经处理后的排放要求,介绍了5种常用村镇生活污水处理工艺的特点,并针对其适用范围和优缺点进行横向对比,为村镇生活污水处理工艺选择提供参考. 相似文献
11.
12.
13.
14.
15.
《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
16.
17.
感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
18.
从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献
19.
20.
The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献