Perfluorosulfonates and perfluorocarboxylates in snow and rain in Dalian,China

Samples of precipitation events (snow and rain) in Dalian, a typical coastal town in China, were analyzed for perfluorosulfonates (PFSAs) and perfluorocarboxylates (PFCAs) to investigate atmospheric contamination by these compounds. In the snow event on December 16, 2006, samples were collected from 21 different sites and in another 6 precipitation events, samples were collected from a single location. Four PFSAs (C4, C6, C8, C10) and seven PFCAs (C6–12) were analyzed. Among the homologues, perfluorooctane sulfonate (PFOS) concentrations were the highest with a geometric mean (GM) of 145 ng/L (n = 21) during the snow event on December 16, 2006, followed by perfluorooctanoate (PFOA) with a GM of 24.7 ng/L (n = 21). Concentrations of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS) and perfluoroheptanoate (PFHpA) were more than two orders of magnitude lower than that of PFOS. Other PFSAs and PFCAs were found to be below the limit of detection in all the samples. In other 6 precipitation events, PFSAs and PFCAs were detected approximately in the same order of magnitude in both snow and rain. The results indicate that wet deposition may be a potential transport mechanism of perfluorinated chemicals in the environment.     

The Sustainable Development of ICTs in China： An Empirical Study of Small and Medium-Sized Enterprises

The wide application of new information and communication technologies （ICTs） has been argued to be critical to business success of small and medium-sized enterprises （SMEs）, especially to those in the developing countries. Drawing upon existing literature, this article will examine the determinants of ICTs application in SMEs in China based on data collected from interviews with top managers and/or owners of 70 SMEs. We identify 20 factors affecting ICTs application in SMEs in China and divide them into four broad categories, namely pressures, firm specific factors, technical factors and local milieu. We also pay special attention to the Chinese business environment affecting ICTs application. Our analysis shows that local ICT infrastructure, external pressures from competitors and ICT knowledge of employees are the determinants of Internet application by SMEs, while product characteristics and market target are important factors of e-commerce adoption.     

China-Indian Silk Trade： Current Production and Future Prospects

As an important traditional labor-intensive industry of both India and China, the cocoon silk industry has long made great contributions to the ecological environment protection, rural economic development and the increase in export income of both countries. India is not only a very important cocoon silk trading partner, but an important production competitor of China. In recent years, there has been a large increase in the production and trade of the cocoon silk between China and India; however, China relies heavily on Indian market, which leads to a tendency of further deterioration in the silk trade environment between both countries. The present article makes an empirical study of the cocoon silk resources of the two countries and the scale, product mix and market structure of China-Indian silk trade from 2001 to 2007. Overall silk trading volumes from China to India and market concentration rate are on the increase because of the superiority of Chinese cocoon silk production over that of India. Owing to scattered market share and export that mainly focused on raw materials product, there has been a phenomenon of price reduction and quantity increase. India carries out fierce competition with China in the international market and even imposes antidumping sanction on Chinese silk, which are key factors restricting further increase between China-India trade. Based on the abovementioned facts, the authors aim to put forward suggestions for steadily developing the production and trade of China＇s silk.     

Evolution Rules of Urban-rural Development and Inspiration for China’s Agriculture

Based on urban-rural contrast coefficient,this article designs the agriculture relative development index(ARDI) as indicators measuring the intensity of urban-rural dual structure which is comparable among the countries of the world.This article calculates ARDI of 40 countries from 1980 to 2004.The result shows that ARDI in the developed countries and most of the middle-income countries are rising and yet there are declines in most of the low-income countries.The result also showed that most countries’ ARDI...     

Characterization of aluminium-based water treatment residual for potential phosphorus removal in engineered wetlands

Aluminium-based water treatment residual (Al-WTR) is the most widely generated residual from water treatment facilities worldwide. It is regarded as a by-product of no reuse potential and landfilled. This study assessed Al-WTR as potential phosphate-removing substrate in engineered wetlands. Results indicate specific surface area ranged from 28.0 m² g⁻¹ to 41.4 m² g⁻¹. X-ray Diffraction, Fourier transform infrared and energy-dispersive X-ray spectroscopes all indicate Al-WTR is mainly composed of amorphous aluminium which influences its phosphorus (P) adsorption capacity. The pH and electrical conductivity ranged from 5.9 to 6.0 and 0.104 dS m⁻¹ to 0.140 dS m⁻¹ respectively, showing that it should support plant growth. Batch tests showed adsorption maxima of 31.9 mg P g⁻¹ and significant P removal was achieved in column tests. Overall, results showed that Al-WTR can be used for P removal in engineered wetlands and it carries the benefits of reuse of a by-product that promotes sustainability.     

太湖蓝藻水华的遥感监测研究

随着太湖蓝藻水华的日益严重,实现藻类的时空动态监测成为湖泊水质保护亟待解决的问题.利用遥感技术可以快速、直观地获取整个水域水质的时空变化情况,为实现藻类的动态监测提供了有效的途径.在太湖蓝藻水华遥感监测研究结果的基础上,总结分析了现有研究中所使用的遥感数据源、遥感监测方法以及遥感反演的水质参数,讨论了现有研究中存在的问题,并对将来的发展趋势进行了展望.     

季铵化合物对环境的影响及微生物降解研究进展

季铵化合物(QACs)作为最主要的阳离子表面活性剂,被认定为一种需要深入研究的潜在有害物质.美、日、欧地区学者已经对QACs展开了广泛研究,而国内只对其分析监测方法作了一些初步探索,在环境领域对于QACs的研究还鲜有报道.综述了QACs在城市污水处理厂以及自然水体中的分布特征、环境风险、降解特性以及降解机制等方面的研究进展,并对QACs的环境影响以及生物降解的研究方向进行了探讨,对相关研究人员具有一定的参考价值.     

颗粒化序列间歇式活性污泥反应器工艺处理化粪池污水

在序列间歇式活性污泥反应器(SBR)中成功培养出适应化粪池污水水质的好氧颗粒污泥.并将其应用于化粪池污水的处理.在好氧颗粒污泥培养的第15天左右,SBR中开始出现细小的颗粒,然后微生物在其上繁殖生长使颗粒逐渐增大而成熟;在第24天时,SBR中絮状活性污泥已基本实现了颗粒化.培养出的好氧颗粒污泥对化粪池污水有稳定的处理效果,在进水完全为化粪池污水时,COD、NH_4~+-N、TN的平均去除率分别为77%、61%、47%.但是,由于化粪池污水COD较低,因此无法维持较高的生物量,在后期的稳定运行过程中MLSS始终维持在2 500 mg/L左右.好氧颗粒污泥的同步硝化反硝化作用是其稳定脱氮的保证.     

污泥膨胀状态下原生动物群落结构分析

系统研究了丝状菌膨胀与非丝状菌膨胀2种典型污泥状态下原生动物的群落结构特征及其演变规律。伴随丝状菌的大量增殖,原生动物总量相应减少,匍匐型纤毛虫及有壳类肉足虫数量迅速上升,占据明显的优势地位,典型原生动物为斜管虫（Chilodonella sp.）、小轮毛虫（Trochilia minuta）以及匣壳虫（Centropyxis sp.）;非丝状菌污泥膨胀对原生动物总量及种群结构影响较小,伴随粘性菌胶团的大量出现,各功能类群的比例变化较小,但原生动物总量持续增加,其中菌食性纤毛虫呈线性增加,典型原生动物为钟虫（Vorticella sp.）。     

一株高效脱硫脱氨氮菌的分离、鉴定及系统发育分析

从运行稳定的能同步脱臭的曝气生物滤池中采集样品,富集分离获得一株能高效脱硫脱氨氮的菌株TS-1。对分离菌株进行形态观察、生理生化试验及16S rRNA基因序列分析,结果表明,该菌株TS-1为革兰氏阳性菌,杆状;菌落在营养琼脂培养基上呈圆形,表面光滑,乳白色半透明;V-P试验阴性,能水解淀粉和明胶,利用柠檬酸盐生长;对菌株进行16S rRNA的PCR扩增,扩增产物测序结果表明分离菌株TS-1与巨大芽孢杆菌（Bacillus megaterium）同源性达到99%;以16S rRNA同源性为基础构建了包括24株相关种属细菌在内的系统发育树,在系统发育树中,分离菌株TS1与Bacillus megaterium在同一分支。结合形态观察、生理生化试验及16S rRNA基因序列分析结果,将其初步鉴定为巨大芽孢杆菌（Bacillus megaterium）。在常温（30±2）℃、转速为150 r/min的条件下,处理pH 7、S^2-和NH⁺₄-N分别为80 mg/L和88 mg/L的水样40 h,硫化物和氨氮的脱除率分别为91.8%和96.6%。