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排序方式: 共有1810条查询结果,搜索用时 46 毫秒
981.
Dennis T. Burton Ronald J. Klauda Lenwood W. Hall Jr Michael A. Jepson 《Water research》1984,18(11):1365-1376
Twenty-day-old striped bass (Morone saxatilis) larvae were exposed to a range of treated bleached kraft mill effluent (BKME) concentrations from 0 to 20% effluent by volume (v/v) under continuous flow test conditins. The experimental test concentrations in the 2–20% BKME test aquaria had a BOD5 which ranged from < 1 to 5 mg l−1, TSS 12–17 mg l−1, and true color 35–416 mg l−1. Bleached kraft mill effluent did not kill larvae exposed to it for 20 days through metamorphosis to the juvenile stage. The BKME did not alter growth in length, weight or condition factor in larvae over the 20-day exposure period as determined by multiple regression analysis. A linear regression analysis on the dry weight data at Day 20 only, however, indicated a trend of decreasing weight with increasing BKME concentration. Effluent-exposed larvae also developed normally during the 20-day study. All individuals examined completed the transformation from postlarvae to juveniles by the age of 40 days. 相似文献
982.
大量电动汽车充电会加大充电站负荷峰谷差,影响充电站安全稳定运行。因此提出了一种基于思维进化算法(MEA)的电动汽车有序充电控制策略:以用户充电费用最少和充电站负荷峰谷差最小为目标函数,采用MEA算法动态计算接入充电站电动汽车的最优充电时段,由用户自主响应,从而实现充电站内电动汽车的有序充电控制。为验证该策略的有效性,利用蒙特卡洛方法模拟用户充电需求,对算例进行仿真分析。结果表明:与无序充电相比,有序充电控制策略可在降低电动汽车用户费用的基础上实现充电负荷的削峰填谷;相比于使用遗传算法,MEA算法具有一定优势。 相似文献
983.
Ani Abraham Natalia A. MacDonald Edward L. Dreizin 《Propellants, Explosives, Pyrotechnics》2016,41(5):926-935
Different reactive materials were prepared and evaluated as potential heaters to evaporate refractory and readily ionized samarium metal. Fully dense, nanocomposite powders of thermites and boride‐forming compounds were prepared using arrested reactive milling. In some samples, samarium powder was blended with the nanocomposite powders; in other samples samarium was added using an additional short milling step. Powders were pressed in pellets and ignited at a low pressure. Flame propagation was monitored optically; combustion products were collected and analyzed. It was observed that nanocomposite 2B‐Ti powder, in which samarium was added via an additional milling step was most suitable for evaporating samarium, while preventing its reaction with other material components. Up to 30 wt‐% of samarium could be added and most of it evaporated in the presented experiments. 相似文献
984.
985.
986.
粗粒铀矿石提取和浓酸熟化-高铁淋滤浸出法 总被引:1,自引:0,他引:1
本文在分析常规铀水冶技术存在的问题和薄层浸出法局限性的基础上,叙述了一种新的浸出体系-浓酸熟化-高铁淋滤浸出法。该法采用硫酸高铁溶液淋滤熟化矿石,完成了薄层浸出法所不能完成的残余浸出反应。浓酸熟化-高铁淋滤浸出法对我国铀矿石具有很强的适应性,是一种可与常规搅拌浸出法相竞争的粗粒矿石提取技术。以该法为基础的铀矿加工流程将可成为我国新一代铀水冶基本流程之一。该流程省去了矿石细磨,因而从根本上克服了由矿石磨细所带来的一系列困难;同时不排放工艺流出液,可改变当前铀水冶的面貌。 相似文献
987.
循环强化垂直流人工湿地处理猪场污水 总被引:10,自引:0,他引:10
对含高浓度有机物和氮磷的养殖场污水采用复合垂直流人工湿地进行处理,并考察了回流出水的循环强化处理效果。结果表明:循环出水显著提高了对BOD5、COD、SS和NH^ 4 -N的去除率,且对BOD5的去除满足Monod方程;大部分NH^ 4 -N被硝化,对NH^ 4 -N的去除率与其表面负荷率呈线性关系;随着硝化反应的进行,碱度减少,pH值不断降低;循环出水可引入部分氧气,延长了污染物和附着于植物根系微生物的接触时间,提高了对污染物的去除率。 相似文献
988.
989.
N, O-carboxymethyl chitosan (NOCC) composite nanofiltration (NF) membranes were prepared by coating and cross-linking. The fermentation effluent from a wine factory was treated with the resulting NOCC/polysulfone (PSF) composite NF membranes. The permeate flux and the removal efficiencies of the resulting NF membranes for the color, chemical oxygen demand (CODcr), total organic carbon (TOC), and conductivity of the fermentation effluent were investigated in relation to the driving pressure, the feed flow, and the operation time. The permeate flux and the removal efficiencies were found to increase with the increase of the driving pressure or the feed flow. At 0.40 MPa and ambient temperature the removal efficiencies were 95.5%, 70.7%, 72.6%, and 31.6% for color, CODcr, TOC, and conductivity, respectively. The membrane was found to be stable over a 10-h ooeration for the fermentation effluent treatment. 相似文献
990.
Hichem Smaoui Hajer Guermazi Serge Agnel Youssef Mlik Alain Toureille 《Polymer International》2000,49(11):1513-1518
To improve the performance of insulators, space charge measurements and localisation are of fundamental importance. For this purpose we have utilised the thermal step method (TSM) which allows measurement of the space charge density within the material. The object of this study is to characterise the electric state of epoxidic polymer material used in electrical insulation, and to study the influence of different factors involving the appearance and the evolution of space charge. The influence of poling temperature as well as the manufacturing process of the material on the remaining space charge distribution is also studied. Measurements show that the space charge behaviour was influenced by two factors: the poling temperature and the manufacturing process. © 2000 Society of Chemical Industry 相似文献