氧化还原修复重金属污染土壤的文献计量学分析

基于Web of Science和中国知网(CNKI)的数据源,选择对应数据库、设定年限,检索相关文献和专利,运用文献计量学方法,并借助Origin、Excel等绘图制表工具对数据结果进行了统计、分析和对比,比较直观地展现出重金属污染土壤氧化还原修复技术的总体情况、国内外发展现状和趋势、国内外发展差距,并从关键词的发展演替角度分析研究热点与方向,为氧化还原修复技术相关学科发展与研究等提供决策参考。     

人类活动影响下衡水市地下水环境演化进程分析

人类活动尤其是人为过度开采地下水,控制和制约着天然地下水环境的演化进程。本文分析了衡水市近50年来大规模超量开采地下水导致衡水市出现地下水动力场变异、含水介质空间结构变异以及地下水化学场变异等问题,分析深部地下水循环系统动力场时空演化规律、地面沉降发展规律以及地下水化学环境的演化规律。自20世纪50年代以来,人类活动影响下衡水市地下水环境的演化经历了原始共生、地下水采补均衡、地下水采补失衡以及生态环境恶化的过程。     

汽油火车装车台油气回收装置运行分析

介绍了中国石化济南分公司2005年投入使用的油气回收装置的工艺流程、主要设备、工艺参数及实施效果。分析数据表明：济南分公司油气回收装置的应用,经济效益和社会效益明显,符合安全、环保、健康的清洁生产理念。     

Concentrations of heavy metals and polycyclic aromatic hydrocarbons in needles of Masson pine (Pinus massoniana L.) growing nearby different industrial sources

Emissions from industrial activities pose a serious threat to human health and impose the need for monitoring both inorganic and organic pollutants in industrial areas.We selected Masson pine (Pinus massoniana L.) as potential biomonitor and collected the current (C) and previous year (C+1) needles from three industrial sites dominated by petrochemical,ceramics manufacturing,and iron and steel smelting plants and one remote site to determine heavy metals (Cu,Cd,Pb,Zn,Cr,Ni and Co) and polycyclic aromatic hydrocarbons (PAHs) in unwashed and water-washed needles.Both unwashed and washed C+1 needles showed generally higher concentrations of heavy metals and PAHs than C needles,although the washed needles more clearly spotlighted the accumulation effect of PAHs over exposure time.Water-washing resulted in a significant decrease in needle PAH concentrations with more significant effects shown in C needles.By contrast,needle heavy metal concentrations were much less affected by washing.Although heavy metals and PAHs might differ in adsorption and uptake strategies,their higher concentrations in the needles at the industrial sites indicated conspicuous contamination due to industrial emissions there,The PAH distribution patterns in pine needles accorded with the real types of energy consumption in the study sites and were efficiently used for pinpointing local pollutant sources.     

清洁生产审核在淀粉企业的应用

清洁生产是企业可持续发展的必由之路,清洁生产审核是企业实现清洁生产最成熟最有效的手段。在对某淀粉企业进行清洁生产审核中,针对行业特点,结合企业自身情况,提出并实施无／低费方案20项,中／高费方案5项。取得了良好的效益,在改善厂区环境的同时,每年可节水64500吨,节电约31万度,减少废水排放48000吨。该企业初步实现了在提高企业自身资源回收利用能力的同时,达到经济、环境和社会效益的统一,为淀粉企业今后的清洁生产审核积累了经验。     

Performance and microbial community analysis of an algal-activated sludge symbiotic system: Effect of activated sludge concentration

It was focused on the effect of different sludge concentrations on the performances of an algal-activated sludge symbiotic system in terms of wastewater treatment, algal-activated sludge characteristics and community structure. The results showed that the highest nutrient removal efficiencies were obtained in the reactor R~2 with soluble chemical oxygen demand(sC OD), ammonia nitrogen(NH_4~+-N) and phosphate(PO_4~(3-)-P) removal efficiencies of(90.6 ± 2.3)%,(97.69 ± 2.6)% and(83.81 ± 2.3)%, respectively. Further investigation exhibited that sludge concentration has a great effect on the dissolved oxygen(DO) concentration, the pH, the growth of algae and the extracellular polymeric substance(EPS) production, which resulted in influencing the settleability and the performance of symbiotic system. The denaturing gradient gel electrophoresis(DGGE) analysis demonstrated that the sludge concentration had a selective power for particular members of algae. Meantime, the stimulated algal population would selectively excite the members of bacteria benefited for the formation of algal-bacterial consortia.The variation of microbial compositions, which was influenced by the different sludge concentrations, might be ultimately responsible for the different treatment performances.     

A Water Yield‐Oriented Practical Approach for Multifunctional Forest Management and its Application in Dryland Regions of China

Mountainous forest areas are vitally important for water supply in dryland regions which suffer from high erosion risk and severe water shortage. Massive afforestation, mainly for erosion control, may reduce the water yield and threaten local water supply security. Moreover, many over‐dense forests due to a strict logging ban policy have produced remarkably negative impacts for both forests (e.g., low timber quality, restricted natural regeneration, and high stand instability) and water yield. To satisfy the rapidly increasing demands on water supply and other services, a practical approach for managing forest stands in a multifunctional way, which particularly addresses water yielding, is urgently required. For this purpose, we integrated the existing knowledge and experience, designed an “ideal” stand structure to represent multifunctional forest (MFF) and determined its key parameters (a ground coverage of >0.7, a canopy density around 0.7, and an H/DBH ratio (tree height [m] to the diameter at breast height [cm]) of <0.7). Moreover, a decision process for MFF stand management was recommended as: (1) investigating the site quality; (2) identifying the site‐specific main forest functions; (3) quantifying the stand structure; (4) diagnosing the stand structure by comparing with the “ideal” one; and (5) arranging the functions/structure‐oriented management measures. In this way, the water‐yielding function can be improved and meanwhile other forest functions can be promoted.     

Immobilization of lead in anthropogenic contaminated soils using phosphates with/without oxalic acid

Understanding the effects of oxalic acid (OA) on the immobilization of Pb(II) in contaminated soils by phosphate materials, has considerable benefits for risk assessment and remediation strategies for the soil. A series of phosphate amendments with/without oxalic acid were applied to two anthropogenic contaminated soils. We investigated the immobilization of Pb(II) by KH₂PO₄, phosphate rock (PR), activated phosphate rock (APR) and synthetic hydroxyapatite (HAP) at different phosphate:Pb (P:Pb) molar ratios (0, 0.6, 2.0 and 4.0) in the presence/absence of 50 mmol oxalic acid/kg soil, respectively. The effects of treatments were evaluated using single extraction with deionized water or CaCl₂, Community Bureau of Reference (BCR) sequential extraction and toxicity characteristic leaching procedure (TCLP) methods. Our results showed that the concentration of water extractable, exchangeable and TCLP-Pb all decreased with incubation time. The concentration of water-extractable Pb after 120 days was reduced by 100% when soils were amended with APR, HAP and HAP + OA, and the TCLP-Pb was <5 mg/L for the red soil at P:Pb molar ratio 4.0. Water-soluble Pb could not be detected and the TCLP-Pb was <5 mg/L at all treatments applied to the yellow-brown soil. BCR results indicated that APR was most effective, although a slight enhancement of water-soluble phosphate was detected at the P:Pb molar ratio 4.0 at the beginning of incubation. Oxalic acid activated phosphates, and so mixing insoluble phosphates with oxalic acid may be a useful strategy to improve their effectiveness in reducing Pb bioavailability.     

Spatial distribution,pollution level,and health risk of Pb in the finer dust of residential areas: a case study of Xi'an,northwest China

Environmental Geochemistry and Health - The spatial distribution, pollution level, and exposure risk of Pb in the finer dust (particle size?&lt;?63&nbsp;μm) of residential...     

A Compatible Interface of Wheat Straw/Polylactic Acid Composites Collaborative Constructed Using KH570–Nano TiO2

Journal of Polymers and the Environment - Poor interfacial compatibility between wheat straw and polylactic acid (PLA) remains a problem that directly affects the overall performance of wheat...