Determination of total petroleum hydrocarbons (TPH) in agricultural soils near a petrochemical complex in Guangzhou,China

The total petroleum hydrocarbons (TPH) pollution in regional agricultural soils was investigated. Seventy soil samples collected from surface layers (0–20 cm) and horizons of five selected pedons in the vicinity of a petrochemical complex in Guangzhou, China were analyzed, and the vertical variation and spatial variability of TPH were evaluated. The TPH concentration in top soils around the petrochemical complex ranged from 1,179.3 to 6,354.9 mg kg^− 1, with the average of 2,676.6 mg kg^− 1. Furthermore, significant differences between land-use types showed that the TPH concentration in top soils was strongly influenced by accidental spills. Both the TPH trends in pedons and the identified hot-spot areas also showed that the accidental explosions or burning accidents were mainly responsible for the pollution. The results reported here suggest that the regular monitoring and inspection shall be conducted for safety and to avoid or minimize the accidents, and the effective measures should be taken to remediate the contaminated areas and to assure that the important industrialization of Guangzhou area would not mean human health risks near the petrochemical complex.     

75％戊唑·嘧菌酯可溶性粉剂对3种昆虫的急性毒性与初级风险评估

为明确75％戊唑·嘧菌酯可溶性粉剂对意大利蜜蜂、玉米螟赤眼蜂和家蚕的急性毒性和初级风险.采用国标《化学农药环境安全评价试验准则》(GB/T 31270—2014)中的4种方法,包括饲喂法(蜜蜂经口)、点滴法(蜜蜂接触)、药膜法(赤眼蜂)和浸叶法(家蚕),分别测定了该农药对上述3种非靶标昆虫的急性毒性,并根据国标《农药登记环境风险评估指南》(NY/T 2882—2016)把这些结果用于该药的初级风险评估.结果表明,75％戊唑·嘧菌酯可溶性粉剂对意大利蜜蜂的急性接触毒性48 h半致死剂量(48 h-LD50)为>105μg·蜂-1,急性经口毒性48 h-LD50为65.9μg·蜂-1,对蜜蜂的风险可接受(风险商(RQ)=0.135≤1).对玉米螟赤眼蜂的急性毒性24 h半致死用量(24 h-LR50)为2.81×10-6 mg·cm-2,对玉米螟赤眼蜂的农田内和农田外喷雾场景风险均不可接受(危害商HQin=1199>5,HQoff=24.2>5).对家蚕的急性毒性96 h半致死浓度(96 h-LC50)为596 mg·L-1,对家蚕的喷雾场景下的最外围桑树风险不可接受(RQ=7.47>1),次外围桑树风险可接受(RQ=0.457≤1).对不可接受的风险,宜采取风险减轻措施,如喷雾施药期间禁止释放赤眼蜂,避免在桑园周围喷雾法施药等,以达到保护非靶标环境生物的目的.     

西安城区冬季污染天单颗粒气溶胶的化学组分特征及混合状态

本研究利用单颗粒气溶胶质谱仪(SPAMS)于2018年12月6-12 日在西安市开展高时间分辨率的实时在线观测.观测期间颗粒物数浓度和PM2.5质量浓度变化趋势一致,表明颗粒物数浓度可以反映大气污染状况.结合自适应共振神经网络算法和人工分类方法,将颗粒物共分为7类,分别是元素碳颗粒(EC)、有机碳与元素碳混合颗粒(OC...     

The abatement of major pollutants in air and water by environmental catalysis

This review reports the research progress in the abatement of major pollutants in air and water by environmental catalysis. For air pollution control, the selective catalytic reduction of NO _x (SCR) by ammonia and hydrocarbons on metal oxide and zeolite catalysts are reviewed and discussed, as is the removal of Hg from flue gas by catalysis. The oxidation of Volatile organic compounds (VOCs) by photo- and thermal-catalysis for indoor air quality improvement is reviewed. For wastewater treatment, the catalytic elimination of inorganic and organic pollutants in wastewater is presented. In addition, the mechanism for the procedure of abatement of air and water pollutants by catalysis is discussed in this review. Finally, a research orientation on environment catalysis for the treatment of air pollutants and wastewater is proposed.     

RAPD扩增中商品酶体系对扩增产物的影响

随机选用了10条RAPD引物，采用3种商品TapDNA聚合酶体系，以5个不同物种的动植物总DNA为模板，进行RAPD扩增，实验发现，在对同一模板、采用同一引物进行的RAPD扩增中，仅仅因为使用了不同的商品TaqDNA聚合酶，获得的扩增产物差别极大；不同商品来源的PCR反应缓冲体系，对扩增产物也有一定影响，但相对较小，这说明，不同的商品酶体系对RAPD扩增产物影响很大，因此，影响RAPD扩增产物稳定性的一个关键因素是商品TaqDNA聚合酶本身；研究中前后一致地使用同一商品TaqDNA聚合酶体系，是成功进行RAPD分析的基础。     

A pyrazine based metal-organic framework for selective removal of copper from strongly acidic solutions

● pz-UiO-66 was synthesized facilely by a solvothermal method. ● Efficient capture of copper from highly acidic solution was achieved by pz-UiO-66. ● pz-UiO-66 exhibited excellent selectivity and capacity for copper capture. ● Pyrazine-N in pz-UiO-66 was shown to be the dominant adsorption site. The selective capture of copper from strongly acidic solutions is of vital importance from the perspective of sustainable development and environmental protection. Metal organic frameworks (MOFs) have attracted the interest of many scholars for adsorption due to their fascinating physicochemical characteristics, including adjustable structure, strong stability and porosity. Herein, pz-UiO-66 containing a pyrazine structure is successfully synthesized for the efficient separation of copper from strongly acidic conditions. Selective copper removal at low pH values is accomplished by using this material that is not available in previously reported metal–organic frameworks. Furthermore, the material exhibits excellent adsorption capacity, with a theoretical maximum copper uptake of 247 mg/g. As proven by XPS and FT-IR analysis, the coordination of pyrazine nitrogen atoms with copper ions is the dominant adsorption mechanism of copper by pz-UiO-66. This work provides an opportunity for efficient and selective copper removal under strongly acidic conditions, and promises extensive application prospects for the removal of copper in the treatment for acid metallurgical wastewater.     

震害预测中建筑物属性信息提取方法研究

在编制城市抗震防灾规划工作中,如何得到规划区大量的建筑物的普查资料一直是一个重要的课题。就此,本文提出了一种基于RS技术通过首先旋转高分辨率遥感图像而后搜寻建筑物阴影区有效分割线段来实现大范围建筑物层数信息提取的新方法,并结合高分辨率遥感影像数据和实际建筑物层数信息对提取结果进行分析。结果表明计算模型正确,普适性较强,算法过程简单,所得结果精度满足城市震害预测基础信息的要求,有较大实用价值。     

浅谈系统论方法在防汛抗灾工作中的应用

本文以系统论方法为指导,概括地分析了防汛抗灾系统的组成、特征以及系统论方法对防汛抗灾工作的作用,并结合防汛抗灾工作的实际,应用系统论的基本原理,提出了防汛抗灾系统整体与要素的组织管理方法,探讨了如何充分发挥防汛抗灾系统的整体功能,取得最佳运行效果的途径。     

Bio-reduction of arsenate using a hydrogen-based membrane biofilm reactor

Arsenate (As(V)) is a carcinogen and a significant problem in groundwater in many parts of the world. Since As(III) is generally more mobile and more toxic than As(V), the reduction of As(V) to As(III) is not a conventional treatment goal. However, reducing As(V) to As(III) may still be a means for decontamination, because As(III) can be removed from solution by precipitation or complexation with sulfide or by adsorption to Fe(II)-based solids. A promising approach for reducing oxidized contaminants is the H2-based membrane biofilm reactor (MBfR). In the case of arsenate, the MBfR allows bio-reduction of As(V) to As(III) and sulfate to sulfide, thereby giving the potential for As removal, such as by precipitation of As2S3(s) or formation of Fe(II)-based solids. When As(V) was added to a denitrifying MBfR, As(V) was reduced immediately to As(III). Decreasing the influent sulfate loading increased As(V) reduction for a fixed H2 pressure. A series of short-term experiments elaborated on how As(V) loading, nitrate and sulfate loadings, and H2 pressure controlled As(V) reduction. Lower nitrate loading and increased As(V) loading increased the extent of As(V) reduction, but increased H2 pressure did not increase As(V) reduction. As(V) reduction was sensitive to sulfate loading, with a maximum As(V)-removal percentage and flux with no addition of sulfate. As(III) could be precipitated with sulfide or adsorbed to Fe(II) solids, which was verified by scanning electron microscopy and energy dispersive X-ray analysis.     

Use of hematological and plasma biochemical parameters to assess the chronic effects of a fungicide propiconazole on a freshwater teleost

Blood is an indicator of physiological condition of an animal. Therefore, the chronic effects of propiconazole, a triazole fungicide present in aquatic environment, on hematology of rainbow trout were investigated in this study. Fish were exposed at various concentrations of PCZ (0.2, 50 and 500 μg L(-1)) for 7, 20 and 30 d. Multiple biomarkers were measured, including hematological indices (hemoglobin concentration, red blood cells count, hematocrit, leukocyte count, mean erythrocyte hemoglobin, mean erythrocyte volume and mean color concentration) and plasma biochemical parameters (ammonia, glucose, total proteins, creatine kinase, lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase). Through principal component analysis and integrated biomarker response assessment, influence extent induced by PCZ-stress of each test group was distinguished. Additional, all parameters measured in this study displayed different dependent patterns to PCZ concentrations and exposure time by two-way ANOVA. The results of this study indicate that chronic exposure of PCZ has altered multiple physiological indices in fish hematology and CK activity may be an early biomarker of PCZ toxicity; however, before these parameters are used as special biomarkers for monitoring residual PCZ in aquatic environment, more detailed experiments in laboratory need to be performed in the future.