野外测量条件对石油污染地下水常规水化学参数的影响

通过原位水质监测仪监测某石油类污染地下水的6项常规水化学指标,研究不同测量方式、不同测量深度对其产生的影响。结果表明:受石油污染的地下水水面以下0.5 m处,原、异位测量的水温、p H值、溶解氧、氧化还原电位、浊度均有不同程度的差异。在对比研究期内,可观测到这种差异最大可达:水温5~6℃,p H值0.2,溶解氧3.0 mg/L,氧化还原电位11 m V,浊度55 NTU。这种地下水环境条件的改变,必然会引起一系列水文地球化学、生物地球化学反应的变化。原位测量水深0.5~4 m范围内,水温随深度增加逐渐增大,最大变幅0.16℃;p H随深度增加变化不大;DO受温度和生化耗氧作用影响,随深度增加而降低;ORP与DO变化趋势大致相同,最大减幅达62 m V;电导率随地下水深度增加其值不变;最大浊度值113 NTU出现在水深4 m处。     

猴年寄语--人类濒危表亲"黑名单"

就目前所知,20世纪里没有哪种灵长类动物走向灭绝。这似乎是一个令人欣慰的记录,因为当今世界每天都有约100种物种在灭绝。可是,千万不要高兴太早,刚刚进入新世纪就有一种非洲疣猴灭绝了。可以说,包括人类在内的动物王国正日益面临生态环境全面退化的厄运。原因很简单,人的数量和人的欲望正在急剧增长,这使十余种人类的表亲,从     

Experimental analysis of the evaporation process for gasoline

This paper presents the findings from a study on the evaporation process of 93 RON (research octane number) unleaded gasoline. The parameters measured in the experiment included the weight, the RVP (Reid vapor pressure) and the viscosity of gasoline, the concentration of NMHC (non-methane total hydrocarbon) in the oil vapor and the concentration of the main vapor constituent. Results showed that the parameters changed significantly as evaporation processed. The weight loss reached 86.36% after 300 days and presented a logarithmic curve with time. The RVP decreased from 38 kPa to 9.6 kPa. The viscosity of gasoline increased from 8.6 × 10^?4 Pa s to 1.51 × 10^?3 Pa s. All the concentrations of NMHC and the main constituent of vapor decreased in varying amounts. Most of the changes might be attributed to the evaporation of volatile hydrocarbons.     

环境空气中短链氯化石蜡研究进展

短链氯化石蜡(SCCPs)是碳链长度为10至13个碳原子的正构烷烃氯代衍生物。SCCPs具有持久性、生物累积性、长距离迁移能力、以及毒性作用。SCCPs已被《关于持久性有机污染物的斯德哥尔摩公约》增列为持久性有机污染物审查范围内,引起了全球关注。SCCPs在环境各介质及生物体内均有检出,近年来,在室内空气和灰尘中也检出了大量SCCPs,其已成为人体暴露的一个重要来源。本文就大气环境及室内空气与灰尘中氯化石蜡(CPs)的采样与分析方法、污染水平与来源,及人体暴露概况进行了综合阐释,以期为我国大气和室内环境中CPs的研究工作提供参考。     

Effective removal of Cd2+ and Pb2+ pollutants from wastewater by dielectrophoresis-assisted adsorption

Dielectrophoresis (DEP) process could enhance the removal the Cd²⁺ and Pb²⁺ with less absorbent. The removal rates of both Cd²⁺ and Pb²⁺ increased with the increase of voltage. The overall removal rate of Cd²⁺ and Pb²⁺ in the binary system is higher than that of Cd²⁺ or Pb²⁺ in the single system. DEP could cause considerable changes of the bentonite particles in both surface morphology and microstructure. Dielectrophoresis (DEP) was combined with adsorption (ADS) to simultaneously and effectively remove Cd²⁺ and Pb²⁺ species from aqueous solution. To implement the process, bentonite particles of submicro-meter size were used to first adsorb the heavy metal ions. These particles were subsequently trapped and removed by DEP. The effects of the adsorbent dosage, DEP cell voltage and the capture pool numbers on the removal rate were investigated in batch processes, which allowed us to determine the optimal experimental conditions. The high removal efficiency, 97.3% and 99.9% for Cd²⁺ and Pb²⁺, respectively, were achieved when the ions are coexisting in the system. The microstructure of bentonite particles before and after ADS/DEP was examined by scanning electron microscopy. Our results suggest that the dielectrophoresis-assisted adsorption method has a high capability to remove the heavy metals from wastewater.     

油田修井起下杆管清洁生产技术现状及分析

文章从现有杆管清洁设备的基本结构、工作原理、应用效果入手,分析了井下、井口、井场、车间4个环节15种杆管清洁生产技术的优缺点和适应性,同时引入技术成熟完备性指标,对每种杆管清洁生产技术作了定量评价,认为在施工中应综合考虑地层、井史、油田所处环境敏感性等影响因素,将其集成或组合使用,形成适合于不同类型油井的杆管清洁模式。建议继续加强井下泄油、油管内壁清洗、内防喷、井口防喷防溅等关键设备研发与完善,提高清洁生产技术的适应性、可靠性,以降低劳动强度,提高工作效率。     

Diversity in industrial ecosystems

Within the natural world, diversity refers to the variety and variability among living organisms and the ecological complexes in which they occur. Its complexity is measured in terms of variations at genetic, species and ecosystem levels. It plays a critical role in meeting human needs while maintaining the ecological processes upon which our survival depends. This paper agues that such a natural metaphor should be considered in industrial systems in order to realise sustainable development. This article begins by describing natural biodiversity, emphasising its definition and value, and its maintenance. Next, the paper discusses the rationale and mechanisms for encouraging industrial diversity. The authors suggest that this natural metaphor provides a useful guide on how businesses in an industrial system can evolve towards greater resilience and sustainability.     

Removal of multicomponent VOCs in off-gases from an oil refining wastewater treatment plant by a compost-based biofilter system

Waste gases from oil refining wastewater treatment plants are often characterized by the presence of multicomponent and various concentrations of compounds. An evaluation of the performance and feasibility of removing multicomponent volatile organic compounds (VOCs) in off-gases from oil refining wastewater treatment plants was conducted in a pilot-scale compost-based biofilter system. This system consists of two identical biofilters packed with compost and polyethylene (PE). This paper investigates the effects of various concentrations of nonmethane hydrocarbon (NMHC) and empty bed residence time (EBRT) on the removal efficiency of NMHC. Based on the experimental results and practical applications, an EBRT of 66 s was applied to the biofilter system. The removal efficiencies of NMHC were within the range of 47%–100%. At an EBRT of 66 s, the average removal efficiency of benzene, toluene, and xylene were more than 99%, 99%, and 100%, respectively. The results demonstrated that multicomponent VOCs in off-gases from the oil refining wastewater treatment plant could be successfully removed in the biofilter system, which may provide useful information concerning the design criteria and operation of full-scale biofilters.     

卤代有机污染物抑制甲状腺激素代谢酶活性的研究进展

甲状腺激素(thyroid hormones,THs)对生物体细胞的正常发育和分化至关重要,甲状腺激素失调可引起中枢神经系统、肺、心血管和其他器官的异常发育。研究表明,环境中的卤代有机污染物(halogenated organic contaminants,HOCs)及其代谢产物具有甲状腺激素干扰效应。抑制参与THs代谢的生物酶,例如磺基转移酶(sulfotransferases,SULTs)和脱碘酶(deiodinases,DIs),是HOCs及其代谢产物干扰THs正常功能的重要方式。本文重点综述了HOCs对不同甲状腺激素代谢酶的抑制效应的研究,讨论了环境计算化学和预测毒理学方法在该领域的重要应用,期望为HOCs干扰甲状腺激素酶代谢活性的深入研究提供借鉴与参考。     

Biogeochemical zonation of sulfur during the discharge of groundwater to lake in desert plateau (Dakebo Lake,NW China)

As one of the important elements of controlling the redox system within the hyporheic and hypolentic zone, sulfur is involved in a series of complex biogeochemical processes such as carbon cycle, water acidification, formation of iron and manganese minerals, redox processes of trace metal elements and a series of important ecological processes. Previous studies on biogeochemistry of the hyporheic and hypolentic zones mostly concentrated on nutrients of nitrogen and phosphorus, heavy metals and other pollutants. Systematic study of biogeochemical behavior of sulfur and its main controlling factors within the lake hypolentic zone is very urgent and important. In this paper, a typical desert plateau lake, Dakebo Lake in northwestern China, was taken for example within which redox zonation and biogeochemical characteristics of sulfur affected by hydrodynamic conditions were studied based on not only traditional hydrochemical analysis, but also environmental isotope evidence. In the lake hypolentic zone of the study area, due to the different hydrodynamic conditions, vertical profile of sulfur species and environmental parameters differ at the two sites of the lake (western side and center). Reduction of sulfate, deposition and oxidation of sulfide, dissolution and precipitation of sulfur-bearing minerals occurred are responded well to Eh, dissolved oxygen, pH, organic carbon and microorganism according to which the lake hypolentic zone can be divided into reduced zone containing H₂S, reduced zone containing no H₂S, transition zone and oxidized zone. The results of this study provide valuable insights for understanding sulfur conversion processes and sulfur biogeochemical zonation within a lake hypolentic zone in an extreme plateau arid environment and for protecting the lake–wetland ecosystem in arid and semiarid regions.