Quantitative method to determine the regional drinking water odorant regulation goals based on odor sensitivity distribution：Illustrated using 2-MIB

Taste and odor （T/O） in drinking water often cause consumer complaints and are thus regulated in many countries. However, people in different regions may exhibit different sensitivities toward WO. This study proposed a method to determine the regional drinking water odorant regulation goals （ORGs） based on the odor sensitivity distribution of the local population. The distribution of odor sensitivity to 2-methylisobomeol （2-MIB） by the local population in Beijing, China was revealed by using a normal distribution function/model to describe the odor complaint response to a 2-MIB episode in 2005, and a 2-MIB concentration of 12.9 ng/L and FPA （flavor profile analysis） intensity of 2.5 was found to be the critical point to cause odor complaints. Thus the Beijing ORG for 2-MIB was determined to be 12.9 ng/L. Based on the assumption that the local FPA panel can represent the local population in terms of sensitivity to odor, and that the critical FPA intensity causing odor complaints was 2.5, this study tried to determine the ORGs for seven other cities of China by performing FPA tests using an FPA panel from the corresponding city. ORG values between 12.9 and 31.6 ng/L were determined, showing that a unified ORG may not be suitable for drinking water odor regulations. This study presents a novel approach for setting drinking water odor regulations.     

建设项目环境影响后评价的主要内容及存在的问题研究

根据《中华人民共和国环境影响评价法》的有关条款,探讨了建设项目环境影响后评价的定义、适用对象、工作内容、工作程序。同时,结合多年的环境管理经验,分析了典型行业环境影响后评价的重点,并指出了目前中国建设项目环境影响后评价存在的问题,提出了改进和完善的建议。实践表明,开展环境影响后评价有助于提高环境管理决策水平。     

西藏浪卡子至洛扎公路沿线地质灾害与防治

浪卡子至洛朴公路是西藏山南地区环线公路的西段,全长120 km。由于公路位于高寒、新构造运动强烈的地区,特殊的地质背景、气候因素和鹅理环境,为该地区地质灾害的发育提供了良好的条件。公路沿线的地质灾害主要有泥石流、滑坡、坍岸(水毁)等,各类地质灾害影响公路总长7 248m,其中泥石流42条,滑坡l处,坍岸(水毁)12处。各类地质灾害对公路的建设和运营构成了极大的危害,针片这些地质灾害发育的特点,结合当地的环境和公路的等级要求,提出了切实有效的治理措施。     

Metabolic uncoupler, 3,3′,4′,5-tetrachlorosalicylanilide addition for sludge reduction and fouling control in a gravity-driven membrane bioreactor

• Effects of metabolic uncoupler TCS on the performances of GDMBR were evaluated. • Sludge EPS reduced and transformed into dissolved SMP when TCS was added. • Appropriate TCS increased the permeability and reduced cake layer fouling. • High dosage aggravated fouling due to compact cake layer with low bio-activity. The gravity-driven membrane bioreactor (MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements. However, the growing sludge not only increases membrane fouling, but also augments operational complexities (sludge discharge). We added the metabolic uncoupler 3,3′,4′,5-tetrachlorosalicylanilide (TCS) to the system to deal with the mentioned issues. Based on the results, TCS addition effectively decreased sludge ATP and sludge yield (reduced by 50%). Extracellular polymeric substances (EPS; proteins and polysaccharides) decreased with the addition of TCS and were transformed into dissolved soluble microbial products (SMPs) in the bulk solution, leading to the break of sludge flocs into small fragments. Permeability was increased by more than two times, reaching 60–70 L/m²/h bar when 10–30 mg/L TCS were added, because of the reduced suspended sludge and the formation of a thin cake layer with low EPS levels. Resistance analyses confirmed that appropriate dosages of TCS primarily decreased the cake layer and hydraulically reversible resistances. Permeability decreased at high dosage (50 mg/L) due to the release of excess sludge fragments and SMP into the supernatant, with a thin but more compact fouling layer with low bioactivity developing on the membrane surface, causing higher cake layer and pore blocking resistances. Our study provides a fundamental understanding of how a metabolic uncoupler affects the sludge and bio-fouling layers at different dosages, with practical relevance for in situ sludge reduction and membrane fouling alleviation in MBR systems.     

太阳热反射涂料的研制

根据涂料反射太阳热的原理,以丙烯酸树脂为基料,以金红石型钛白粉、云母粉及空心玻璃微珠为原料,制备了隔热性能和耐候性能均良好的太阳热反射隔热涂料,并研究了颜料、填料种类、粒径、涂层厚度对涂料隔热性能的影响。     

铝材Sn-Ni混合盐电解着枪色参数研究

首先对铝片试样进行预处理,随后在恒定的电流密度和相同的氧化时间下,在铝材表面形成厚度均匀的阳极氧化膜,然后采用方波交流电,对铝试样进行电解着色处理,通过改变铝材电解着色工艺的着色时间、电流密度、正负电流比、占空比等因素来研究这些因素与铝材明度值和色差之间的关系。实验结果表明获得枪色的最佳工艺条件是:着色时间6m in左右,着色电流密度为1.40 A/dm2左右,正向电流比负向电流大7%左右,占空比55%左右。     

湖北长江三峡地区山水林田湖草生态保护修复形势与对策研究

文章重点分析了湖北长江三峡地区生态功能定位、生态保护修复重点,剖析了湖北长江三峡地区山水林田湖草生态保护修复形势,在介绍湖北长江三峡地区山水林田湖草生态保护修复工程试点的基础上,深入分析了该工程试点推进中的难点问题。提出了相应对策：坚持用系统思维推进山水林田湖草整体保护和修复;加强生态环境问题突出区域重点攻坚,着力解决生态保护修复不充分、不平衡问题;加大社会资本、绿色金融支持力度,健全多元化、差异化资金供给及管理机制;积极探索生态产品及废弃资源价值转化新途径;加强科技支撑、坚持自主创新、打造精品示范工程;提升建设项目服务水平,加强生态环境监测及风险应急能力建设。     

聚α-烯烃合成油的清洁生产工艺

针对聚α-烯烃合成油（PAO）生产旧工艺存在的问题,介绍了以固载化AlCl3为催化剂的PAO生产新工艺,考察了各种因素对PAO收率的影响。实验结果表明,在反应温度为100℃、反应时间为8h、A1C1,与α-烯烃质量比为10：75的条件下,PAO收率为48．8％。采用新工艺后,PAO产品质量有了明显提高,黏度指数为132,碱和白土的消耗为零,且没有废渣产生,可实现清洁化生产。     

环境水中西维因残留的检测方法

综述了酶传感器、酶联免疫传感器、液相色谱、荧光光谱和流动注射化学发光等方法在环境水西维因残留检测中的应用,对各种分析方法的工作原理作了简要介绍,并对其应用前景作了展望.     

Polybrominated diphenyl ether in the East Asian environment: a critical review

Polybrominated diphenyl ethers (PBDEs) have been extensively used as flame retardants in consumer goods. Sufficient evidence shows that PBDEs have been rapidly accumulating in the environment worldwide. In Asia, deca-bromodiphenyl ether has been produced and used in large quantities, while penta-BDE has largely ceased in the mid-1990s. This paper summarizes and critically reviews the status of PBDE pollution in East Asia, with emphases on the comparisons with Europe and North America and the interpretation of the differences. In general, the concentrations of PBDEs in atmosphere, sludge, human and biological samples of East Asia are comparable to or lower than those in Europe and North America. However, in the sediments of waters near densely populated and heavily industrialized areas, PBDE levels are among the highest ever reported in the literature. In Japan and China, concentrations of PBDEs in sediment cores showed an increasing trend for the past 20-30 years. Also, PBDEs levels in human breast milk in Japan increased about 10-fold in the past 20 years. The presence of PBDEs in fur seal has increased about 150-fold in 1994 than that in 1972. Regional and inter-continental transport cannot be confirmed due to insufficient information. However, the detection of a number of PBDE congeners in a pristine lake on the Qinghai-Tibet Plateau may be an evidence of their long-range transport.