测压法和稀释接种法测定BOD5的比较

介绍仪器测压法原理及测定方法,对测压法的准确度与精密度进行了测试,结果为:准确度相对误差在-6.6%￣7.1%之间,精密度相对偏差在-7.5%￣6.0%之间,均符合国家标准质控要求。通过测压法与稀释接种法对质控样及废水的测试比对,结果表明两种测试方法的相对误差、相对偏差无显著差异,且均符合国家标准质控要求。测压法克服了稀释接种法操作繁琐等缺点,具有测定直接、操作简便等优点,有一定的可用性。     

心语

三角形的全等具有传递性,比如若有△ABC≌△DEF,△DEF≌△MNP,则一定有△ABC≌△MNP．这个性质在解题时有很重要的应用．     

测压法和稀释接种法测定BOD5的比较

介绍仪器测压法原理及测定方法,对测压法的准确度与精密度进行了测试,结果为：准确度相对误差在-6.6%～7.1%之间,精密度相对偏差在-7.5%～6.0%之间,均符合国家标准质控要求.通过测压法与稀释接种法对质控样及废水的测试比对,结果表明两种测试方法的相对误差、相对偏差无显著差异,且均符合国家标准质控要求.测压法克服了稀释接种法操作繁琐等缺点,具有测定直接、操作简便等优点,有一定的可用性.     

光叶楮白皮生物法制浆废水的分析

在光叶楮的生物制浆和过氧化氢漂白工艺研究的基础上,对制浆漂白所产生的废水作后续处理研究,并对漂白的各段废水特性进行检测。     

浅议呼和浩特市辛辛板污水处理BOD5与CODcr的相关性

文章通过呼和浩特市辛辛板污水处理厂一期、二期工程的运行,对BOD5与CODcr的相关性进行了研究。     

测压法BOD5测定的探讨

对BOD5的测压法测定做了较全面的探讨.指出该法经不同倍数稀释的测定值之间的差异,验证了该测定法可以表征毒性物质对微生物活性的抑制程度.通过模拟含毒性染料的印染废水活性污泥的处理,指出其不同稀释比的BOD5值可作为该处理法的设计和运行管理的重要参数.     

活性污泥法多变量最优控制的遗传算法实现

针对最优控制传统算法存在的一些问题,着重研究了采用遗传算法在限制有机物排放总量时,使污水处理运行费用最低的最优控制问题,提出了一种新的污水处理最优控制问题的计算方法,提高了计算效率.     

按需出版及其对图书馆的影响

按需出版是近十年来印刷出版行业的新事物。本文系统地介绍了国内外按需出版的情况,并分析了其优势及面临的问题,进而分析按需出版对图书馆的影响。图书馆将在文献收藏、馆藏分配方面受其影响。     

民办高校董事会制度变迁的动因分析

民办高校董事会制度变迁是各个利益主体经过多次博弈达到均衡的产物,其实质是制度创新,是我国民办高校法人治理的核心.制度环境的变革是民办高校董事会制度变迁的外在动力;而民办高校自身存在的一些深层次矛盾,是董事会制度变迁的内在动因.     

Quality of effluents from Hattar Industrial Estate

Of 6634 registered industries in Pakistan, 1228 are considered to be highly polluting. The major industries include textile, pharmaceutical, chemicals （organic and inorganic）, food industries, ceramics, steel, oil mills and leather tanning which spread all over four provinces, with the larger number located in Sindh and Punjab, with smaller number in North Western Frontier Province （NWFP） and Baluchistan. Hattar Industrial Estate extending over 700 acres located in Haripur district of NWFP is a new industrial estate, which has been developed with proper planning for management of industrial effluents. The major industries located in Hattar are ghee industry, chemical （sulfuric acid, synthetic fiber） industry, textile industry and pharmaceuticals industry. These industries, although developed with proper planning are discharging their effluents in the nearby natural drains and ulti- mately collected in a big drain near Wah. The farmers in the vicinity are using these effluents for growing vegetables and cereal crops due to shortage of water. In view of this discussion, there is a dire need to determine if these effluents are hazardous for soil and plant growth. So, effluents from different industries, sewage and normal tap water samples were collected and analysed for pH electrical conductivity （EC）, total soluble salts （TSS）, biological oxygen demand （BOD）, chemical oxygen demand （COD）, total nitrogen, cations and anions and heavy metals. The effluents ofghee and textile industries are highly alkaline. EC and TSS loads of ghee and textile industries are also above the National Environmental Quality Standards （NEQS）, Pakistan. All the effluents had residual sodium carbonates （RSCs）, carbonates and bicarbonates in amounts that cannot be used for irrigation. Total toxic metals load in all the effluents is also above the limit i.e. 2,0 mg/L. Copper in effluents of textile and sewage, manganese in ghee industry effluents and iron contents in all the effluents were higher than NEQS. BOD and COD values of all the industries are also above the NEQS. On the whole, these effluents cannot be used for irrigation without proper treatment otherwise that may cause toxicity to soil, plants and animals as well add to the problems of salinity and sododicity. Similarly, these effluents cannot be used for fish farming.