电渗析技术在浓盐水回收项目的应用研究

电渗析技术作为一种新兴的膜分离技术,因高效率低能耗、对预处理要求低、对分离组分选择性高、原水回收率高、环境友好等优点,在国内外各行业获得广泛应用.江苏华晖环保科技有限公司改进了电渗析工艺参数,并在贵州开磷(集团)有限责任公司进行了推广应用,大大降低了出水中Cl-和Ca2+浓度,电导率由数千us/cm降到200 us/cm以下.电渗析技术可节约水资源,社会、环境、经济效益显著,对企业实现真正的“零排放”具有巨大的推动力.     

地理数据库的构建及其在水利工程环境影响评价中的应用研究

GIS技术为环境影响评价提供了高效的操作平台和有力的技术支撑,应用GIS技术建立的地理数据库,有助于科学地分析、预测和评估工程实施对周边环境可能造成的影响.文章简述了地理数据库的模块结构及构建流程,并结合贵州省夹岩水利枢纽及黔西北供水工程环境影响评价工作对地理数据库在图件制作、环境敏感目标识别、水文信息提取与分析、生态影响评价等方面的应用进行了介绍.最后指出GIS技术相对于传统评价技术的优点,并对其应用前景进行了展望.     

Lead (Pb) exposure and heart failure risk

Environmental Science and Pollution Research - Lead (Pb) is a heavy metal with widespread industrial use, but it is also a widespread environmental contaminant with serious toxicological...     

Characterization,source apportionment and risk assessment of PAHs in urban surface dust in Shenyang city,China

Environmental Geochemistry and Health - Characteristics, profile composition, ecological and human health risk of polycyclic aromatic hydrocarbons in surface dust collected from Shenyang city,...     

Temporal variability in trace metal solubility in a paddy soil not reflected in uptake by rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.)

Alternating flooding and drainage conditions have a strong influence on redox chemistry and the solubility of trace metals in paddy soils. However, current knowledge of how the effects of water management on trace metal solubility are linked to trace metal uptake by rice plants over time is still limited. Here, a field-contaminated paddy soil was subjected to two flooding and drainage cycles in a pot experiment with two rice plant cultivars, exhibiting either high or low Cd accumulation characteristics. Flooding led to a strong vertical gradient in the redox potential (Eh). The pH and Mn, Fe, and dissolved organic carbon concentrations increased with decreasing Eh and vice versa. During flooding, trace metal solubility decreased markedly, probably due to sulfide mineral precipitation. Despite its low solubility, the Cd content in rice grains exceeded the food quality standards for both cultivars. Trace metal contents in different rice plant tissues (roots, stem, and leaves) increased at a constant rate during the first flooding and drainage cycle but decreased after reaching a maximum during the second cycle. As such, the high temporal variability in trace metal solubility was not reflected in trace metal uptake by rice plants over time. This might be due to the presence of aerobic conditions and a consequent higher trace metal solubility near the root surface, even during flooding. Trace metal solubility in the rhizosphere should be considered when linking water management to trace metal uptake by rice over time.     

高产施肥条件下水稻穗粒数与茎粗关系

在三个高产水稻课题的研究和推广过程中，研究了水稻的穗粒数与茎粗之间的关系，其关系符合直线方程Y=a＋bX。因此认为在水稻栽培中．必须培育茎秆粗壮的高产群体。     

Reductive Degradation of Tetrabromobisphenol Using Iron-Silver and Iron-Nickel Bimetallic Nanoparticles with Microwave Energy

In this work, a novel combined system by Fe-Ag or Fe-Ni nanoparticles and microwave (MW) radiation were used for the debromination of tetrabromobisphenol A (TBBPA) in aqueous solutions. Core-shell structure bimetallic nanoparticles were prepared by replacement reaction in liquid phase and then characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy techniques. MW radiation can enhance the degradation of TBBPA by Fe-Ag or Fe-Ni observably. The rate of reduction reactions for bimetallic nanoparticles under MW were first compared with those under conventional heating conditions. Compared with nano-iron, the deposition of Ag or Ni also accelerated the debromination, and Fe-Ag was more reactive than Fe-Ni toward TBBPA reduction. Removal efficiencies increased with increasing Fe-Ag dosage and MW energy level. Major reduction products of TBBPA identified by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) were tri-BBPA, di-BBPA, mono-BBPA, and BPA, which indicated a stepwise debromination process. It provides an effective technology for TBBPA laden wastewater treatment.     

氢化物发生-原子荧光法同时测定污水中的砷和硒

用HNO3-HClO4消解液消解水样,断续流动进样,在KBH4-酸体系中,采用氢化物发生-原子荧光法同时测定污水中的砷和硒。在含浓盐酸2．0mL的介质中加入硫脲-抗坏血酸溶液5mL,在温度高于15℃时放置30min后,以15g/L KBH4溶液为还原剂,5％(体积分数)HCl为载流测定砷、硒荧光强度。在最佳实验条件下,砷、硒的相对标准偏差分别小于4％和2％,检出限分别为0．89μg／L和0．51μg／L,加标回收率分别为91．5％～101．2％和94．0％～100．5％。该方法精密度高、测定结果稳定,达到环境监测要求。     

土壤-植物系统中模拟酸雨与Cd复合污染的短期环境效应--黄豆盆栽试验

通过盆栽实验,研究了在黄豆(Glycne max)的一个生长周期内,模拟酸雨与Cd复合污染对土壤基本性质的影响,模拟酸雨作用下土壤-植物系统中Cd的迁移转化规律以及模拟酸雨与Cd复合污染对黄豆生长与生理特性的影响,探讨了土壤-植物系统中这种复合污染的短期环境效应.结果表明,短期内模拟酸雨和Cd污染对土壤-植物系统都有致害作用,但Cd污染的效应大于模拟酸雨的效应,模拟酸雨与Cd复合污染环境效应大于这2种污染物的单因素效应,且表现出明显的协同作用.在本试验条件下,pH值为3.5的模拟酸雨和20 mg·kg-1Cd的处理组合对土壤-植物系统的危害最严重.尽管在短期内,协同作用仅在土壤交换态Cd含量、黄豆茎和根中的Cd含量这3项指标上得到一定程度的体现,但这种复合污染的化学机制和环境效应值得关注,这2种污染物长时期共同作用对土壤-植物系统的影响也值得深入研究.