电解对氯苯酚稀水溶液中脱氯降解机理研究

利用石墨电极进行了多种条件下对氯苯酚水溶液的电解研究。研究结果表明,CODCr去除率和脱氯率随电压的升高呈先升高后下降的趋势、随对氯苯酚质量浓度的升高呈指数下降、随溶液pH的升高而升高。碱性条件下电解效果明显优于中性和酸性条件。在电压为10V,pH≈12,电解100mg L的对氯苯酚溶液2h后,CODCr去除率可达52 94%,脱氯率达52 8%。由脉冲辐解瞬态吸收光谱可知,中性、酸性条件下降解机制均为OH·自由基的作用,经过瞬态分子OH-adducts(OH加合物)的中间产物进一步氧化降解;碱性条件下通过OH·自由基和对氯苯酚氧基负离子的阳极直接失电子氧化作用2种降解机制,经过瞬态分子氯代酚氧自由基中间产物氧化降解对氯苯酚,产物分析结果显示生成了对苯二酚和苯醌等中间产物。      

农村水塘系统对非点源水污染的调控作用研究

以辽阳市沙岭镇大闯屯村为例,对北方平原地区农村水塘系统污染现状、非点源污染物的迁移途径、控制方法进行了初步研究,研究结果表明,农田径流与村落生活污水的排放方式对农村地表水环境质量具有重要影响,进行合理的生态设计,充分利用自然净化单元,对改善地表水环境质量将会起到积极的作用。     

Conversion of waste plastics into value-added carbon materials

Plastic pollution is a major environmental issue worldwide, calling for advanced methods to recycle waste plastics in the context of the circular economy. Here we review methods and strategies to convert waste plastics into value-added carbon materials, with focus on sources, properties, pretreatment of waste plastics, and on preparation of carbon materials. Pretreatment techniques include mechanical crushing, plastic stabilization and electrospinning. Carbon materials such as carbon nanotubes, graphene, carbon nanosheets, carbon spheres and porous carbon are prepared by oxygen-limited carbonization, catalytic carbonization, the template-based method, and pressure carbonization. We emphasize the conversion of polyethene terephthalate, polyethylene, polypropylene, polystyrene, halogenated plastics, polyurethane and mixed plastics.

     

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.     

鲤鱼对2,6-二硝基甲苯的生物浓缩、消除与代谢研究

 以鲤鱼为实验生物，应用流动式摄取及释放装置，进行了2，6－二硝基甲苯（2，6－DNT）的生物浓缩与释放研究。取得了2，6－DNT在鲤鱼（全鱼）、肝及肠部的生物浓缩曲线。全鱼的浓缩曲线可以稳态（平台式）曲线描述，但是肝、肠部浓缩曲线均呈峰形。肝部峰快速下降后渐趋稳态，肠部峰下降未得稳态。峰形，肝在先，肠在后。对比2，6－DNT在全鱼及肝、肠的生物浓缩曲线，并参照报道_（1，2）指出，全鱼摄取曲线上各点所表现的浓度值为各时刻鱼体内各组织摄取化学品总重对全鱼重量的比值。肝、肠部峰形曲线预示了在肝、肠内生物浓缩过程发生了生物转化作用。对全鱼的生物浓缩过程应用单区一级动力学模型，求得BCF值与消除速率常数K₁与K₂，由K₁/K₂计算得到的BCF值与实测值相符。释放较慢，释放曲线呈双曲线形，半减期为4.8h。     

气相色谱法测定固定污染源废气中氯甲基甲醚和二氯甲基醚的研究

氯甲基甲醚(CMME)和二氯甲基醚(BCME)属于确认人类致癌物,因此,建立精准、绿色的CMME和BCME检测分析方法十分必要。基于2,4,6-三氯苯酚+乙醇钠+乙醇衍生化体系,利用气相色谱法(电子捕获检测器)测定了固定污染源废气中的CMME和BCME,并且系统地优化了采样条件、衍生化条件,确定了衍生化产物的结构及衍生比率。结果表明：工作曲线相关系数均大于0.990;当采样量为10 L时,检出限均为0.003 mg/m³;当实际样品加标量分别为0.010、0.100、1.00 mg/m³时,测定结果的相对标准偏差分别为15%～16%、8.9%～13%、10%～11%,加标回收率分别为89.2%～90.8%、75.3%～78.6%、76.5%～77.2%。     

长三角地区二次电池生产场地土壤重金属污染评价

采用X射线荧光光谱法测定土壤重金属Cd,Cu,Ni,Mn,Co的含量,并选用地积累指数法和潜在生态危害指数法对其进行环境质量评价。结果表明,Cd是各场地中产生污染最为严重的一种金属,几乎各个车间都存在不同程度的Cd污染,外围农田土壤严重的Cd含量超标也说明了这个问题。     

石煤开发利用重金属污染现状调查研究

报道了湖南、江西和浙江三省石煤开发利用过程中石煤、石煤渣、碳化砖、石煤烟尘灰、矿区周围土壤、水体和气溶胶部分重金属含量的调查方法和主要结果。调查结果表明：石煤的开采和利用对周围的土壤、水体和空气产生了一定污染,尤其是剧毒物质Cd和As的污染应引起高度重视。     

Resistance of Villages to Elevated-Road Traffic Noise

The purpose of this study is to evaluate the methods of reducing elevated-road traffic-noise levels in rural residential areas by controlling the relative locations and morphological parameters and to investigate the effect of noise barriers on noise attenuation along elevated roads and building facades in villages. This study selected six morphological parameters and used noise-mapping techniques to estimate the noise attenuation in 60 village sites. The results indicate that ‘quiet areas’ increase by approximately 10% for each additional 100 m increase in the distance between the elevated road and the village. The best strategy for noise reduction is keeping the elevated road 1,000 m away from the village and raising the road height to 20 m. The building façade conditions only affect the traffic noise level attenuation when the buildings are within 100 m of the elevated road. It was found that the cost-effective length of the road noise barrier is 600 m on both sides of the village parallel to the road. The results highlight the importance of using morphology to improve the traffic noise resistance of villages. The landscape shape indices of buildings and roads are the most important parameters that affect the traffic noise attenuation of elevated roads.     

易燃液体仓库安全监控系统研究

通过对易燃液体仓库的潜在危险的分析和研究,以及火灾爆炸危险性分析,说明安全监控技术的重要性。在对监测参数进行分析的基础上,给出了对监测易燃液体仓库的安全监控系统和监测点的布置以及采用合适的探测器。