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971.
律师收费与社会息息相关,随着社会变迁而不断地变革与发展。计划经济时代,国家统一收费机制;有计划的商品经济时代,司法行政机关为主导、律师行业为辅的收费机制;市场经济时代,司法行政机关指导下的律师行业收费机制;转型时期,律师行业收费为主,国家干预为辅的收费机制。 相似文献
972.
Color, TOC and AOX removals from pulp mill effluent by advanced oxidation processes: a comparative study 总被引:2,自引:0,他引:2
Pulp mill effluent containing toxic chemicals was treated by different advanced oxidation processes (AOPs) consisting of treatments by hydrogen peroxide, Fenton's reagent (H2O2/Fe2+), UV, UV/H2O2, photo-Fenton (UV/H2O2/Fe2+), ozonation and peroxone (ozone/H2O2) in laboratory-scale reactors for color, total organic carbon (TOC) and adsorbable organic halogens (AOX) removals from the pulp mill effluent. Effects of some operating parameters such as the initial pH, oxidant and catalyst concentrations on TOC, color, AOX removals were investigated. Almost every method used resulted in some degree of color removal from the pulp mill effluent. However, the Fenton's reagent utilizing H2O2/Fe2+ resulted in the highest color, TOC and AOX removals under acidic conditions when compared with the other AOPs tested. Approximately, 88% TOC, 85% color and 89% AOX removals were obtained by the Fenton's reagent at pH 5 within 30 min. Photo-Fenton process yielded comparable TOC (85%), color (82%) and AOX (93%) removals within 5 min due to oxidations by UV light in addition to the Fenton's reagent. Fast oxidation reactions by the photo-Fenton treatment makes this approach more favorable as compared to the others used. 相似文献
973.
One of the key objectives of regulated charges is to provide efficient price signals to elicit an efficient response by users and maximize social welfare. Nevertheless, current approaches in Europe and elsewhere mainly pursue cost recovery with less attention to economic efficiency. This paper addresses the development of sound and suitable natural gas network charges which should fulfil these and other regulatory principles that have economic and social implications.Considering the main principles as guiding criteria, we analyse Spain as an illustrative case. Current challenges in the design of natural gas charges are examined, and a novel methodology is proposed. 相似文献
974.
以焦化尾水为处理对象,用Fe2+活化S2O82-产生的强氧化性硫酸根自由基对其进行处理,探讨了初始p H,Fe2+和S2O82-投加量对焦化尾水脱色率和COD去除率的影响,并在此基础上进行了正交实验。结果表明:各因素对焦化尾水脱色率和COD去除率影响大小的顺序为n(Fe2+)/n(S2O82-)p Hc(S2O82-);相应的优化条件:p H=3.0,c(S2O82-)=28 mmol/L,n(Fe2+)/n(S2O82-)=0.45。在此优化条件下,处理COD为145~172 mg/L的焦化尾水,常温下反应120 min时,脱色率和COD去除率分别可达89.4%、68.5%。UV-vis分析表明,尾水中的芳香族化合物、多环芳烃等难降解有机物结构易于被破坏,但难以进一步矿化。 相似文献
975.
976.
Sewer misconnections lead to discharge of wastewater direct to rivers and streams. They are difficult to detect due to their intermittent discharges and the wide range of compounds which can be discharged. Optical brighteners are strong indicators of the presence of sewer misconnection discharge in surface water sewers, representative of many components of misconnections, and easily identified. The authors have developed and tested a promising method to identify optical brighteners in sewer systems using inexpensive passive samplers and a simple analysis method. The method is used to identify large areas of four sewer systems which are polluted with misconnection discharge. Limited validation shows that the method successfully indicated diffuse pollution in the surface water sewer system. 相似文献
977.
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
978.
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
979.
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
980.