Evaluation of efficiency of aircraft liquid waste treatment and identification of daily inspection indices: a case study in Changchun, China

Evaluation of the efficiency of aircraft liquid waste treatment has previously been conducted to prevent pollution of the environment. The current study aimed to provide a set of practical methods for efficient airport sanitary supervision. Aircraft liquid waste was collected at Longjia International Airport, Changchun from multiple flights. The efficiency of liquid waste treatment as well as the water quality of the wastewater processed via a second-stage wastewater facility were examined by measuring a number of physical, chemical, and biological indices. Our results indicated that treatment solely via resolvable sanitizing liquid was not sufficient. Although the contents of first-class pollutants all met the requirements of the standard criteria, the contents of a number of second-class pollutants did not satisfy these criteria. However, after further treatment via a second-stage wastewater facility installed at the airport, all indices reached second-grade requirements of the discharge standard. We suggest that daily inspection and quarantine indices at airports should include the suspension content, biological oxygen demands after 5 days, chemical oxygen demand total organic carbon content, amino nitrogen content, total phosphorous content, and the level of fecal coliforms.     

羟基乙叉二膦酸镀铜废液的处理及Cu~(2+)的高附加值资源化回收

采用Na BH4还原法将羟基乙叉二膦酸(HEDP)镀铜废液中的Cu~(2+)制备成纳米铜粉,并采用聚丙烯酰胺(PAM)对还原反应后的废液进行絮凝处理。研究了n(Cu~(2+))∶n(Na BH4)、还原反应温度、还原反应时间及PAM添加量对废液中剩余Cu~(2+)质量浓度的影响,并对回收的纳米铜粉进行了XRD和TEM表征。实验结果表明:当n(Cu~(2+))∶n(Na BH4)=4∶6、还原反应温度为50℃、还原反应时间为2 h时,废液中剩余Cu~(2+)质量浓度降低至1.1 mg/L,Cu~(2+)还原率达99.99%;可获得粒径为20~45 nm的近球型、高纯度、由多晶组成的纳米铜粉;当PAM添加量为10 mg/L时,废液中剩余Cu~(2+)质量浓度降至0.35 mg/L以下,达到GB 21900—2008《电镀污染物排放标准》(小于0.5 mg/L)的要求。     

双酚B对斑马鱼性别分化的影响及作用机制

双酚A(bisphenol A,BPA)是一种典型的内分泌干扰物,双酚B(bisphenol B,BPA)作为其替代物,使用量逐渐增多.一些研究表明,BPB也具有内分泌干扰效应,但是其对鱼类性别分化的影响尚无报道.本文将斑马鱼胚胎暴露于不同浓度的BPB中至受精后60 d(days post fertilization,dpf),研究BPB对斑马鱼性别分化的影响及可能的分子机制.结果表明,10、100和1000μg·L-1的BPB暴露导致斑马鱼性别比例向雌鱼偏离,雄鱼的精巢中发育出初级卵母细胞,并导致斑马鱼体内17β-雌二醇(17β-estradiol,E2)水平升高,睾酮(testosterone,T)水平降低,表明BPB对斑马鱼具有雌激素效应.从基因水平探讨这2种物质导致斑马鱼雌性化的原因,发现BPB使卵巢分化相关基因foxl2的表达水平上升,精巢分化相关基因dmrt1、amh和sox9a表达水平降低,并进一步提高了芳香化酶基因cyp19a1a的转录水平,促进E2的合成,导致斑马鱼的性别分化过程发生异常.     

欧盟化学物质法规管理选择分析对我国化学物质环境管理的启示

法规管理选择分析(RMOA)是欧盟对受关注的化学物质在法定管理方面开展的具体问题具体分析的策略,即"一品一策".其能够促使主管部门在决策化学物质的管控法规时尽快达成共识,并有力地支撑欧盟高关注物质路线图(SVHC Road-map)和一体化规管战略(IRS)的实施.RMOA是一项有效的法规管理与选择决策的程序,但我国对于RMOA的研究尚处于起步阶段.本研究介绍了RMOA这项决策的产生和发展,分析了该决策所取得的成果,阐明了其在欧盟化学物质管理中作用与意义.提出了适合中国化学物质法规管理选择分析的方法,以期对我国化学物质环境风险管理体系的建立健全提供参考.     

Remediation of arsenic contaminated soil by sulfidated zero-valent iron

• Sulfidation significantly enhanced As(V) immobilization in soil by zerovalent iron. • S-ZVI promoted the conversion of exchangeable As to less mobile Fe-Mn bound As. • Column test further confirmed the feasibility of sulfidated ZVI on As retention. • S-ZVI amendment and magnetic separation markedly reduced TCLP leachability of As. In this study, the influences of sulfidation on zero-valent iron (ZVI) performance toward As(V) immobilization in soil were systemically investigated. It was found that, compared to unamended ZVI, sulfidated ZVI (S-ZVI) is more favorable to immobilize As(V) in soil and promote the conversion of water soluble As to less mobile Fe-Mn bound As. Specifically, under the optimal S/Fe molar ratio of 0.05, almost all of the leached As could be sequestrated by>0.5 wt.% S-ZVI within 3 h. Although the presence of HA could decrease the desorption of As from soil, HA inhibited the reactivity of S-ZVI to a greater extent. Column experiments further proved the feasibility of applying S-ZVI on soil As(V) immobilization. More importantly, to achieve a good As retention performance, S-ZVI should be fully mixed with soil or located on the downstream side of As migration. The test simulating the flooding conditions in rice culture revealed there was also a good long-term stability of soil As(V) after S-ZVI remediation, where only 0.7% of As was desorbed after 30 days of incubation. Magnetic separation was employed to separate the immobilized As(V) from soil after S-ZVI amendment, where the separation efficiency was found to be dependent of the iron dosage, liquid to soil ratio, and reaction time. Toxicity characteristic leaching procedure (TCLP) tests revealed that the leachability of As from soil was significantly reduced after the S-ZVI amendment and magnetic separation treatment. All these findings provided some insights into the remediation of As(V)-polluted soil by ZVI.     

Investigation into the nonlinear damage model of coal containing gas

By taking the nonlinear deformation properties of coal into consideration, the nonlinear constitutive equation was founded. And in view of the compressible property of gas, the idea of compressive energy of gas was introduced. According to the continuous damage theory and mesoscopic damage theory, it is assumed that the damage variable has a power function relation with the porosity. By applying the thermodynamics energy conservation laws, a new nonlinear damage constitutive model of coal containing gas was deduced, and the correctness of the new model was verified by comparing with the former experimental results. This model can provide theoretical reference for understanding and solving these dynamic gas disasters such as coal and rock outburst. Moreover, based on this theory, prevention and control measures will be adopted to deal with the dynamic gas disasters according to ever-changing mining conditions.     

美国化学防护服试验与评价用机器人PETMAN研究

美国化学防护服防护因数测试方法-MIST法是评价化学防护服整体防护性能关键技术指标的通行方法,针对现有MIST方法中存在无法对真人采用实际的有毒有害物质对化学防护服进行评价的不足,采用机器人PETMAN替代真人进行MIST试验与评价的需求日益明显。本文针对PETMAN的主要技术构成和相关需求部门提出的要求,详细介绍了研制过程中需要考虑的关键因素,并概述了项目的研究过程以及当前的研究成果。     

节能耐磨型电梯导靴靴衬应用研究

很多电梯使用的导靴靴衬存在容易磨损的问题,从而导致电梯运行中的抖动和不平稳现象,影响乘坐的舒适性。常用的靴衬材料摩擦系数偏大,造成电梯运行过程中摩擦力偏大,能耗增加。因此对这类电梯的导轨与导靴间的摩擦行为进行研究,将新型复合材料应用于电梯靴衬,实现减摩以降低能耗,提升靴衬的耐磨性,延长使用寿命,降低成本,具有较大的实际意义和应用价值。     

藏东南溜砂坡的发育特征与防治

溜砂坡灾害是我国西部山区一种常见的地质灾害,属于广义滑坡中一种特殊类型。我国西藏东南部的溜砂灾害十分发育,危害严重。典型的溜砂坡通常经历碎屑和砂粒的产生、溜动以及在坡脚堆积三个过程。在溜砂坡的形成过程中除重力作用外,发挥主导作用的是物理风化作用。同时,溜砂坡是特殊的环境条件下的产物,研究区溜砂坡多发生于6 000年BP以来,对应于中国石笋记录的季风区在早全新世以来降雨量的减小,是对全球气候变化的响应。溜砂坡可按其砂源形成模式、发育地貌部位与溜砂特征分为原生型溜砂坡和再生型溜砂坡两大类。其中原生型溜砂坡适宜采用避让与清除、排砂工程与拦砂工程等措施,而再生型溜砂坡则应采用砂源区控制工程、固砂工程及拦砂工程等措施。     

基于ISM的区域综合减灾能力评价指标体系研究

分析了区域综合减灾能力的内涵,总结了国内外专家学者对各类减灾能力评价指标的研究进展,结合我国综合减灾工作实际情况,提出了评价区域综合减灾能力的5个一级指标,运用解释结构模型(ISM)定量论证了各指标体系之间的耦合性,证明了一级指标体系的科学性、全面性和综合性。通过对一级指标的细化提出了12个二级指标,考虑评价指标理论完整性的角度,提出了42个三级指标。在此基础上,考虑数据的可获取性,进一步凝练简化为20个三级指标,形成了适用于各类自然灾害、综合考虑灾害发展各个阶段、反映一个区域整体综合减灾能力的区域综合减灾能力评价指标体系。为评价区域综合减灾能力和综合减灾工作成效奠定了基础。