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961.
正The Journal of Environmental Sciences(JES)is honored to welcome Professors/Drs William A.Mitch,Jiuhui Qu,Susan D.Richardson,Jerald L.Schnoor,Hongxiao Tang,Shu Tao,and Hugh A.Tilson to serve on the Editorial Advisory Board(EAB).Their tremendous experience in scientific publications,leading expertise in topic areas pertinent to JES,diverse international networks/perspectives,and exemplary dedication to scientific excellence will guide and help the continuing healthy growth of JES.  相似文献   
962.
The reversibility of the structure and dewaterability of broken anaerobic digested sludge(ADS)is important to ensure the efficiency of sludge treatment or management processes.This study investigated the effect of continuous strong shear(CSS)and multipulse shear(MPS)on the zeta potential,size(median size,d_(50)),mass fractal dimension(D_F),and capillary suction time(CST)of ADS aggregates.Moreover,the self-regrowth(SR)of broken ADS aggregates during slow mixing was also analyzed.The results show that raw ADS with d_(50) of 56.5μm was insensitive to CSS–SR or MPS–SR,though the size slightly decreased after the breakage phase.For conditioned ADS with d_(50) larger than 600μm,the breakage in small-scale surface erosion changed to large-scale fragmentation as the CSS strength increased.In most cases,after CSS or MPS,the broken ADS had a relatively more compact structure than before and d_(50) is at least 200μm.The CST of the broken fragments from optimally dosed ADS increased,whereas that corresponding to overdosed ADS decreased.MPS treatment resulted in larger and more compact broken ADS fragments with a lower CST value than CSS.During the subsequent slow mixing,the broken ADS aggregates did not recover their charge,size,and dewaterability to the initial values before breakage.In addition,less than 15%self-regrowth in terms of percentage of the regrowth factor was observed in broken ADS after CSS at average velocity gradient no less than 1905.6 sec~(-1).  相似文献   
963.
Decabromodiphenyl ether (BDE-209) is a prevalent polybrominated diphenyl ether (PBDE) congener known to have neurotoxicity. Effects of BDE-209 on Neuro-2a cells were performed in the present study and the possible apoptotic pathway was discussed. Results indicated that BDE-209 induced Neuro-2a cell apoptosis, increased the protein expression of Fas and Fas-associated death domain-containing protein (FADD) and activated the caspase-8 and -3 activities in a concentration-dependent manner, inferring the death-receptor pathway was involved in the apoptotic process. Meanwhile, BDE-209 exposure increased the Bax/Bcl-2 ratio and decreased the cellular mitochondrial membrane potential (MMP) which led to cytochrome C released to the cytoplasm. The intracellular caspase-9 was elevated simultaneously, which caused downstream caspase cascade and triggered cell apoptosis. Moreover, BDE-209 exposure increased cellular reactive oxygen species (ROS) level in a concentration-dependent manner and the addition of N-acetyl-l-cysteine (NAC), known as ROS scavengers, obviously reduced the apoptotic rate and a positive relationship was observed between the degree of apoptosis blocking and the loss of MMP and ROS production. We thus concluded that BDE-209 induced Neuro-2a cell apoptosis via the combination of the death-receptor signaling pathway and the mitochondrial signaling pathway. The elevated ROS production was considered to magnify the intracellular apoptosis signal and played a crucial role in apoptosis of Neuro-2a cells induced by BDE-209.  相似文献   
964.
正We are very pleased to announce that five Associate Editors have joined the editorial team of the Journal of Environmental Sciences(JES).Professors/Drs.Yong Cai,Paul Lam,Jonathan Martin,Michael Plewa,and Po Keung Wong bring a wealth of expertise in environmental sciences.As preeminent scientists in their chosen areas of research,they have made outstanding contributions to the discipline of environmental  相似文献   
965.
以小兴安岭湿地为研究对象,分析了不同年代排水造林的森林沼泽湿地土壤溶解性有机碳(DOC)含量变化及生物降解特征,探讨了排水造林时间对土壤DOC及无机氮(NH+4-N+NO-3-N)淋溶动态变化的影响.结果表明:1排水造林时间对土壤DOC含量变化影响显著(p0.05).2003年(PS03)、1992年(PS92)、1985年(PS85)排水造林后的人工兴安落叶松湿地土壤DOC含量均低于未排水造林的天然兴安落叶松苔草湿地(XATC),且排水造林时间越长,土壤DOC含量越少.2在生物降解过程中,土壤DOC的变化趋势表现为初期降解速率较快,而后逐渐减慢并趋于稳定.其中周转时间为1 d的易降解DOC所占比重表现为:PS92XATCPS03PS85,表明排水时间达到一定阈值后,易降解DOC部分可能会转化为难降解部分.3在淋溶过程中,随着淋溶次数的增加,淋出液中DOC含量呈现为先增加后减小的趋势,淋溶1 d后,不同年代排水造林的森林沼泽湿地土壤DOC的淋失率表现为:PS85PS92PS03XATC,表明排水造林时间越长,土壤DOC淋失率越大,因此长时间的排水造林改造可能进一步影响土壤养分的贮量及其有效性.  相似文献   
966.
中国沿海港口总体规划环境影响评价研究   总被引:1,自引:0,他引:1  
中国港口规划环境影响评价自2004年正式启动,至今已经过十余年的探索和发展,各方面都取得了很好的成效,逐步进入到规范化和成熟化阶段。但在中国环境保护发展的新形势下,港口规划环评工作仍在工作机制和技术方法等方面存在诸多问题。本研究系统性回顾了中国港口规划环评的发展历程,梳理了环评管理架构和工作流程,分析了中国港口规划环评存在的主要问题,并从工作机制、成果落实和技术方法等方面提出了相应的对策建议。  相似文献   
967.
采用Daniel趋势检验法对哈尔滨市近年来SO2、NO2和PM10年均浓度变化趋势分析,并对城市总人口与经济、产业结构、民用汽车保有量和能源状况五个城市发展因素进行数据统计分析,用SPSS探究城市发展过程中影响大气污染的因素及相关性.结果表明:浓度变化趋势是SO2明显上升;NO2缓慢上升;PM10整体明显下降,但在2013年点突增至了0.119 mg/m3.SO2与NO2显著相关,相关系数为0.533.经统计,哈尔滨人口经济发展、产业结构调整较为缓慢,全市民用汽车保有量增加并未对NO2浓度影响显著,能源结构依然以煤为主,虽然能源强度提升,但也存在着煤质、散煤的问题.哈尔滨市各城市发展因素与污染物浓度关联度不显著.  相似文献   
968.
969.
970.
The radioactivity of uranium in radioactive coal bottom ash(CBA) may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride(HF) leaching, Siroquant(Rietveld) quantification, magnetic separation, and electron probe microanalysis(EPMA). The Tessier sequential extraction showed that the uranium in the residual and Fe–Mn oxide fractions was dominant(59.1%and 34.9%, respectively). The former was mainly incorporated into aluminosilicates,retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite(Fe_3O_4) and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment.  相似文献   
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