Levels,distribution and risk assessment of hexabromocyclododecane (HBCD) in fish in Xiamen,China

Environmental Monitoring and Assessment - An accidental or intentional contamination event can raise health and sociopolitical concerns, erode public trust, and affect the operation of water...     

pH对氢基质自养微生物还原降解对氯硝基苯的影响

在建立的一种MBfR(氢基质生物膜反应器)中系统考察pH对氢基质自养微生物还原降解p-CNB(对氯硝基苯)的影响,并重点分析pH影响下p-CNB、p-CAN(对氯苯胺)、NO-3-N(硝酸盐)和SO2-4(硫酸盐)的去除效率、通量及当量电子转移通量的变化趋势.结果表明,pH在5.7~8.7之间变化时对硝基还原、还原脱氯、反硝化和硫酸盐还原过程影响显著.氢基质自养微生物生长较适宜的pH范围为6.7~8.2,其中硝基还原、还原脱氯、反硝化和硫酸盐还原的最佳pH分别是7.7、8.2、7.2和7.2.当量电子转移通量分析表明,反硝化和硫酸盐还原对pH变化的敏感性均强于p-CNB还原.为了维持较高水平的p-CNB、NO-3-N和SO2-4同步去除效率,可将pH调控在7.2~8.2之间.适当地调节pH有利于微生物的生长以及控制中空纤维膜表面矿物质沉淀引起的膜污染.     

Projecting Spatial Patterns of Flood Hazard: Recent Climate and Future Changes over Yangtze River Basin

Projection of hazard changes in climate extremes is critical to assessing the potential impacts of climate change on human and natural systems. Using simulations of providing regional climates for impacts studies, five indicators (rainstorm days, maximum 3-day precipitation, elevation, gradient and distance from river or lake) were selected to project the spatial patterns of flood hazard over Yangtze River Basin for the baseline period (1961– 1990) and future (2011–2100) under SRES B2 scenario. The results ...     

废旧电路板上残留焊锡剥离液的研制

以硝酸-磺酸型退锡剂为基础配方,研制了一种脱除废旧电路板表面残留焊锡的剥离液.该剥离液以硝酸为氧化剂,氨基磺酸为稳定剂,苯并三氮唑为铜的缓蚀剂.实验结果表明:剥离液的最佳配比为硝酸浓度3 mol/L,氨基磺酸浓度0.4 mol/L,苯并三氮唑浓度0.08 mol/L;每升剥离液可处理3.5 kg废旧电路板,处理后电路板中的铅离子含量降至100 mg/kg以下.该剥离液处理后的电路板表面的铜箔保持完好,基本没有被剥离液浸蚀.     

Modeling Change-Pattern-Value Dynamics on Land Use: An Integrated GIS and Artificial Neural Networks Approach

The use of spatial methods to detect and characterize changes in land use has been attracting increasing attention from researchers. The objectives of this article were to formulate the dynamics of land use on the temporal and spatial dimensions from the perspectives of the Change-Pattern-Value (CPV) and driving mechanism, based on multitemporal remote sensing data and socioeconomic data. The Artificial Neural Networks were used to identify the factors driving changes in land use. The Pearl River Delta Region of southeast China, which was experiencing rapid economic growth and widespread land conversion, has been selected as the study region. The results show that from 1985 to 2000 in the study region (1) the most prominent characteristics of change in land use were the expansion of the urban land at the expense of farmland, forests, and grasslands, (2) the land-use pattern was being optimized during this period, (3) in an analysis of value, built-up land can yield a return of more than 30 times that of farmland, water area, and forests lands, and (4) rapid economic development, growth in population, and the development of an infrastructure were major driving factors behind ecological land loss and the nonecological land expansion.     

紫球藻的载体培养研究

通过对紫球藻的载体培养进行的较详细研究，获得了适合于紫球藻培养的理想载体；采用载体培养条件的优化和流加营养物质、通气培养以及半连续培养等培养手段，显著提高了紫球藻细胞的质量浓度（ρｍａｘ ＝５．５２ ｇ Ｌ－ １） ． 实验结果表明，利用载体法培养紫球藻不仅能有效地实现高密度培养，易于实现该微藻的连续或半连续培养，而且为细胞的采收带来了很大的方便     

石油化工烟道废气中CO_2高效节能回收利用新型模式的构建

近年来,随着石油化工行业的迅速发展,随之产生的大量温室气体的处理和收集耗费了巨大的能源,因此高效节能回收石油加工中产生的CO2具有重大意义。对国内外CO2的分离技术发展现状进行了综述,并结合石油化工烟道废气的特点,提出一套适合石油化工烟道废气中CO2高效节能回收利用的新型模式。     

SO42-/TiO2-WO3光催化氧化邻硝基苯酚

研究了用H2SO4溶液浸渍处理TiO2-WO3，制备SO4^2-／TiO2-WO3催化剂的方法；考察了该催化剂对邻硝基苯酚的光催化氧化性能。TiO2-WO3的最佳处理工艺条件：H2SO4浓度为0．2mol/L，WO3加入量为3％，于550℃焙烧3h。实验结果表明，反应30min后SO4^2-／TiO2-WO3催化剂可使邻硝基苯酚降解97％；邻硝基苯酚的光催化氧化降解过程遵循一级动力学规律。     

Pros and cons of climate change in China

Climate change strongly affected the structure and functions of natural ecosystems, e.g. the vegetation productivity decreased in the Northeast permafrost region due to the higher temperature and less precipitation, whereas in the Tibetan Plateau, the vegetation productivity increased, owing to the improved thermal resource. Climate change led to reduced precipitation in North and Northeast China and thus the reduced surface runoff. The public needs for energy were changed because of climate change, e.g. the shorter heating period in winter. Climate change profoundly influenced human health, pathophoresis and major projects by increasing extreme events, including frequency and magnitude, and causing more serious water shortage. Under the background of climate change, although the improved thermal resources can be helpful for extending the crop growth period, more extreme events may resulted in more instability in agricultural productivity. Not only did climate change indirectly affect the secondary and tertiary industries through the impacts on agriculture and natural resources, but also climate change mitigation measures, such as carbon tax, tariff and trading, had extensive and profound influences on the socioeconomic system. Further analysis indicated that the impact of climate change presented significant regional differences. The impact had its pros and cons, while the advantages outweighed the disadvantages. Based on the above analysis on the impacts of climate change, we put forward suggestions on coping with climate change. First, scientifically dealing with climate change will need to seek advantages while avoiding the disadvantages of climate change in order to achieve the orderly adaptation to climate change, which is characterized with “Overall best, long-term benefit.” Second, quantitative adaptation should be given more attention, e.g. proposing operational schemes and predictable goals and using uncertainty analysis on adaptation measures. Third, more active coping strategy should be adopted to enhance China’s future comprehensive competitiveness. The strategies include but are not limited to gradually adjusting the industrial structure, intensifying the research and development (R&D) of emission reduction technology and actively responding to the influence of carbon tax, tariff and trading on socioeconomic development in China.     

李氏禾人工湿地净化Cr（Ⅵ）污染水体的性能研究

利用湿生铬超富集植物李氏禾构建的三段式波形潜流式人工湿地,研究了湿地系统对Cr（Ⅵ）污染水体的净化效果。结果显示,李氏禾湿地系统对Cr（Ⅵ）污染水体的净化效果明显好于无植物的对照。当进水Cr（Ⅵ）浓度为2．50mg／L时,李氏禾湿地系统出水Cr（Ⅵ）浓度显著低于对照,说明李氏禾在湿地系统净化Cr（Ⅵ）污染水体中发挥了重要的作用。当进水Cr（Ⅵ）浓度超标150倍（7．50mg／L）时,李氏禾湿地系统出水Cr（Ⅵ）浓度仍可达到国家地表水环境质量标准（0．05mg／L）,表明李氏禾湿地系统具有很强的Cr（Ⅵ）污染净化能力。沿程Cr（Ⅵ）浓度的变化显示,湿地系统对Cr（Ⅵ）的去除效率随水流方向逐渐降低,Cr（Ⅵ）主要在湿地系统的前两个阶段被去除。