Improved selective extraction of 3,3′-dichlorobenzidine by molecularly imprinted polysiloxane microspheres

This report shows an improved selective extraction of the 3,3??-dichlorobenzidine pollutant using molecularly imprinted polysiloxane microspheres (MIPS). 3,3??-Dichlorobenzidine and degradation products are of environmental concern due to their carcinogenic nature. Environmental samples containing 3,3??-dichlorobenzidine are very complex, and the concentration of 3,3??-dichlorobenzidine is usually very low. Current analysis of 3,3??-dichlorobenzidine in environmental matrices often requires cleanup and preconcentration steps that are complex and time-consuming. Therefore, we designed an improved analytical technique. MIPS were synthesized by covalent imprinting. MIPS were characterized by Fourier-transform infrared spectroscopy, nuclear magnetic resonance and transmission electron microscopy. MIPS size ranges from 150 to 250?nm. Adsorption capacity and recognition selectivity toward 3,3??-dichlorobenzidine were studied using ultraviolet spectroscopy and high-performance liquid chromatography. Compared with non-imprinted polysiloxane microspheres, results show that the amount of 3,3??-dichlorobenzidine adsorbed by MIPS is greater by a factor of ten. The binding capacity of MIPS for 3,3??-dichlorobenzidine is seven times larger than diphenylamine. MIPS exhibits high affinity to 3,3??-dichlorobenzidine and can be used for the selective extraction of 3,3??-dichlorobenzidine.     

焦炉烟道气吸氨新工艺研究及其对大气C02减排分析

对利用焦炉烟道气吸氨生产碳酸氢铵的新工艺进行了可行性、减排效果以及经济效益分析。研究表明：用该工艺吸收焦化厂烟道气中CO2生产碳酸氢铵肥料，技术可行，该工艺的工业化将有利于解决焦化厂传统硫铵工艺存在的问题，如需购买原料硫酸、生产运营费用高、污染腐蚀等。年产100万t的冶金焦炭厂可减排CO2温室气体1．34万t，副产碳酸氢铵肥料每年可获利187万元，可实现经济效益和社会效益的双赢，符合可持续发展战略。     

某饮用水处理厂中5种抗生素的去除

通过对美国某饮用水厂处理工艺和对象的介绍,研究各处理单元对克拉霉素(clarithromycin,CLA)、脱水红霉素(erythromycin-H2O,ERY)、左氧氟沙星(levofloxacin,LEV)、新诺明(sulfamethoxazole,SUL)和甲氧苄啶(trimethoprim,TRI)等5种目标抗生素的去除规律;从目标抗生素的残留和各处理单元的去除率角度分别分析时间和空间对去除规律的影响,并探讨抗生素和常规水质参数去除率间的相关关系。研究发现,原水中5种抗生素的平均浓度范围为0～26.8 ng/L,出水降至0～2.3 ng/L,该水厂工艺对5种抗生素的总去除率可达79.5%,其中CLA、ERY、LEV、SUL和TRI的去除率分别为92.8%、24%、100%、85.7%和53.2%;不同采样时间各采样点的抗生素浓度均呈现出秋季高的特点,但各处理单元的处理效率在不同的季节却表现出很大的差异;CLA可作为抗生素总量变化趋势预测的"指示抗生素";抗生素的总量浓度和总去除率与UV254的浓度及去除率之间有很好的正相关性,可以通过对UV254值的测定和去除率的计算来预测抗生素浓度的大小和去除率变化趋势。该研究从抗生素去除角度为我国新建和改扩建饮用水厂工艺提供较好的理论依据。     

Vinasse-based biochar magnetic composites: adsorptive removal of tetracycline in aqueous solutions

Environmental Science and Pollution Research - Highly efficient and cost-effective adsorbents for antibiotic removal are the key to mitigate pollution by industrial wastewaters. Pyrolyzing low-cost...     

Anaerobic ammonium oxidation coupled to ferric iron reduction in the sediment of a eutrophic lake

Environmental Science and Pollution Research - Anaerobic ammonium oxidation coupled to ferric iron reduction (Feammox) has been assumed to play an important role in nitrogen removal from...     

贫营养条件下2种MBR污泥微生物的菌群对比

为了揭示贫营养环境下MBR污泥微生物群落结构的演替和菌群变化的异同,取洗浴再生水、工业再生水MBR的污泥进行周期培养,利用PCR-DGGE和克隆测序技术获得了DNA指纹图谱并建立系统发育树。研究表明,微生物群落结构在贫营养条件下演替明显,洗浴水污泥微生物形成新的优势菌群(Uncultured Pseudomonas)而工业水只维持了原有的部分菌群(Uncultured Sphaerotilus)。2种污泥培养过程中种群多样性变化突出且差异显著。同时洗浴水污泥菌群相似性在培养第8天时发生突变而工业水总体变化平缓。克隆测序表明2种MBR污泥中既有与贫营养环境适生的共性种属又有与各自来源相对应的特性种属。菌群特异性与废水来源紧密相关,是造成2种污泥对贫营养环境适应能力不同的根本原因。     

基于低碳经济的中国外包产业可持续发展研究

全球经济一体化带来了服务外包产业的迅猛发展,服务外包产业的环境污染少、资源消耗低、信息技术承载度高、吸纳就业能力强,已经成为了低碳经济的新增长极。在我国发展低碳经济和产业结构调整的大背景下,研究服务外包产业的发展现状和综合竞争力,对借鉴先进国家的经验,立足本国经济发展实际,探索高效的低碳经济发展模式具有重大意义。如今,软件外包产业作为服务外包的重要组成部分,是全球产业转移的一个新亮点、新趋势。本文结合中国低碳经济发展的必要性和现状,概括和梳理了国内外对于服务外包的相关研究,以事实例证中国软件服务外包产业的发展过程,并通过对我国重点省市软件服务外包产业的综合竞争力和持续发展能力做出的实证分析,认为我国服务外包产业发展潜力巨大;中国的其他省市较北京、上海、广州还存在着比较大的差距;服务外包产业要形成规模化经营,赶超世界一流水平,需要不断提高其知识技术方面的竞争力。     

基于灰色理论的黑龙江省暴雨洪涝特征分析及灾变预测

基于灰色理论和气象灾害普查资料对黑龙江省暴雨洪涝灾害时空分布特征进行了分析并进行了灾变预测。黑龙江省暴雨洪涝灾害主要发生在5-9月,其中7月损失最大;1990年以来暴雨次数虽然有所减少,但暴雨洪涝造成的损失却明显增加;黑龙江省暴雨洪涝灾害可划分为严重洪涝区、重洪涝区、中洪涝区和轻洪涝区,严重洪涝区位于松花江及其支流沿岸的大庆市、伊春市、齐齐哈尔市、佳木斯市和哈尔滨市。根据灰色灾变预测理论预测2013年出现严重暴雨洪涝灾害(全省农作物受灾面积≥500 000 hm2、可比经济损失≥50 000万元)的可能性最大,其次是2016年。     

钝顶螺旋藻固定模拟烟道气中的CO_2

研究了钝顶螺旋藻对模拟烟道气中CO2的固定性能,及其对NOx和SOx水溶形态亚硝态氮、亚硫酸氢根的耐受性。结果显示：随CO2浓度的增加,藻细胞达到最大比生长速率的时间缩短,CO2浓度为15%时藻细胞比生长速率达到最大的时间最短,生物量最终达到最大值4.1 g/L;CO2浓度为15%时藻细胞的固碳率为12.34 mg/（L·h）。研究发现,钝顶螺旋藻能够耐受浓度小于10 mmol/L的亚硝态氮,可将其作为钝顶螺旋藻生长的唯一氮源,但藻生长的延迟期增长。钝顶螺旋藻能够耐受8 mmol/L的亚硫酸氢盐,可将其作为生长的唯一硫源,藻细胞6 d后开始快速增长。     

Saturated hydraulic conductivity of soils in the Horqin Sand Land of Inner Mongolia, northern China

Water is a limiting factor to plant growth in Horqin Sand Land of China. Knowledge of soil saturated hydraulic conductivity (K _sat) is of importance because K _sat influences soil evaporation and water cycling at various scales. In order to analyze the variation of K _sat along with sand types and soil depths, and its relationship with soil physiochemical properties, six typical lands were chosen, including mobile dune, fixed dune, pine woodland, poplar woodland, grassland, and cropland, and K _sat was measured in situ by Guelph Permeameter at each type of land. Soil bulk density, organic matter content, and soil particle size distribution were determined in parallel with K _sat measurement. The results showed that (1) The averaged K _sat was decreased in the order: mobile dune > fixed dune > pine woodland > poplar woodland > grassland > cropland; changes in K _sat varied considerably as soil depth increased, e.g., the changes of K _sat along with soil depth in fixed dune was fitted by exponential model, but it was fitted by parabola model in the pine woodland and grassland. (2) The K _sat values of fixed dune and mobile dune were varied considerably among three slope positions (dune top, windward slope, and leeward slope). (3) The relationships of K _sat and soil physiochemical property revealed that soil bulk density, organic matter content, and coarse sand fraction (2～0.1 mm) were the key factors affecting K _sat in Horqin Sand Land. Compared with clay and silt content proportion, sand fraction in this region showed a more significant positive correlation with K _sat.