日本汽车回收再利用制度对中国的借鉴意义

随着中国<循环经济促进法>的颁布,报废汽车的回收再利用问题引起了更多的关注.在介绍日本汽车回收再利用制度的内容、运行机制及特点的基础上,分析了中国报废汽车回收再利用的现状及存在问题,阐述了日本汽车回收再利用制度对中国的借鉴意义.     

3—（H—酸偶氮）—4—（羟基）—苯磺酸与铁显色反应研究应用

研究了新试剂３—（Ｈ—酸偶氮）—４—（羟基）—苯磺酸（ＨＡＨＢＳ）与铁的显色反应,在ＮＨ４Ａｃ（ｐＨ＝ ７．０）缓冲介质中,ＨＡＨＢＳ和Ｆｅ（Ⅲ）可生成３∶１ 稳定络合物,λｍａｘ ＝ ５５０ ｎｍ ,ε＝ ４．８９×１０４Ｌ·ｍ ｏｌ－ １·ｃｍ － １,铁含量在０～０．６ ｍ ｇ／Ｌ内符合比耳定律。方法用于环境水样中铁的测定,结果令人满意。     

Modeling primary and secondary fractionation effects and atmospheric transport of polychlorinated biphenyls through single-source emissions

The Chinese Gridded Industrial Pollutants Emission and Residue Model (ChnGIPERM) was used to investigate potential fractionation effects and atmospheric transport of polychlorinated biphenyls (PCBs) derived from single-source emissions in China. Modeling the indicative PCBs (CB28, CB101, CB153, and CB180) revealed spatiotemporal trends in atmospheric transport, gas/particle partitioning, and primary and secondary fractionation effects. These included the inference that the Westerlies and East Asian monsoons affect atmospheric transport patterns of PCBs by influencing the atmospheric transport time (ATT). In this study, dispersion pathways with long ATTs in winter tended to have short ones in summer and vice versa. The modeled partitioning of PCB congeners between gas and particles was mainly controlled by temperature, which can further influence the ATT. The potential for primary and secondary fractionation was explored by means of numerical simulations with single-source emissions. Within ChnGIPERM, these phenomena were mainly controlled by the temperature and soil organic carbon content. The secondary fractionation of PCBs is a slow process, with model results suggesting a timescale of several decades.

     

A method for removing persulfate interference in the analysis of the chemical oxygen demand in wastewater

Environmental Chemistry Letters - In recent years, sulfate radical-based advanced oxidation has&nbsp;received increasing attention for the treatment of water and wastewater....     

沼液培养小球藻生产油脂的研究

为了节约微藻生物柴油的生产成本,用沼液作为小球藻生长的培养基,可以得到微藻油脂,还可以净化沼液,从而起到了防治环境污染的作用。研究小球藻在不同浓度沼液(25%、50%、75%和100%沼液浓度)中生长和油脂积累情况,结果表明小球藻在各低浓度沼液(25%、50%沼液浓度)中能很好地生长,延滞期较短,而在高浓度沼液(75%、100%沼液浓度)中,延滞期较长,并且50%浓度沼液培养的小球藻总油脂含量最高。因此选取50%浓度沼液作为小球藻的基本培养基,研究了在50%浓度沼液中,小球藻在不同接种量、光照强度、光暗周期、初始pH条件下的生长和油脂积累情况。得出最适小球藻生长和油脂积累的条件是接种OD值1.023左右、光强4 000 lx、光暗周期20∶4、初始pH值为7.0。     

用微电极测定曝气量对SBR系统中硝化作用的影响

为了研究曝气量对硝化作用的影响,实验采用3个相同的SBR装置,分别在曝气量为4、10和16 L/h的条件下处理人工污水,并采用自制的溶解氧、NO3-、NH4+和pH微电极测定了活性污泥絮体内部微元环境中相应基质的浓度。结果表明,曝气量为4 L/h时,活性污泥絮体内存在厌氧微区,NO3--N浓度减小了,发生了反硝化作用;而曝气量为10 L/h和16 L/h时,活性污泥絮体内发生的都是硝化反应,且NH4+-N浓度的减小量、NO3--N浓度的增大量都随着曝气量的增大而增大,pH随着曝气量的增大而减小。     

Variation of airborne bacteria and fungi at Emperor Qin's Terra-Cotta Museum,Xi'an,China, during the “Oct. 1” Gold Week Period of 2006

Environmental Science and Pollution Research - To stimulate the national economy, a so-called “gold week” comprising May Day and National Day has been put in force by the government,...     

高效集成生物反应器处理生活污水的试验研究

采用高效集成生物反应器(HCR)处理生活污水,考察了水力停留时间、污泥回流比和射流量对污染物去除效果的影响.结果表明,在水力停留时间为90 min,污泥回流比为120%和射流量为2.1 m3/h的最佳运行条件下,HCR对COD、BOD5、NH3-N和SS的去除率分别为82.3%、93.5%、86.3%和93.1%,出水COD、BOD5、NH3-N和SS均达到<城镇污水处理厂污染物排放标准>(GB 18918-2002)中一级B标准.     

Current Nitrogen Management Status and Measures to Improve the Intensive Wheat–Maize System in China

During the first 35 years of the Green Revolution, Chinese grain production doubled, greatly reducing food shortage, but at a high environmental cost. In 2005, China alone accounted for around 38% of the global N fertilizer consumption, but the average on-farm N recovery efficiency for the intensive wheat-maize system was only 16-18%. Current on-farm N use efficiency (NUE) is much lower than in research trials or on-farm in other parts of the world, which is attributed to the overuse of chemical N fertilizer, ignorance of the contribution of N from the environment and the soil, poor synchrony between crop N demand and N supply, failure to bring crop yield potential into full play, and an inability to effectively inhibit N losses. Based on such analyses, some measures to drastically improve NUE in China are suggested, such as managing various N sources to limit the total applied N, spatially and temporally matching rhizospheric N supply with N demand in high-yielding crops, reducing N losses, and simultaneously achieving high-yield and high NUE. Maximizing crop yields using a minimum of N inputs requires an integrated, interdisciplinary cooperation and major scientific and practical breakthroughs involving plant nutrition, soil science, agronomy, and breeding.     

Characteristics and sources of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Shanghai, China

A field campaign was conducted to measure and analyze 13 polycyclic aromatic hydrocarbons (PAHs) in six major zones in the city of Shanghai, P.R. China from August 2006 to April 2007. Ambient air samples were collected seasonally using passive air samplers, and gas chromatography–mass spectroscopy was used in this field campaign. The results showed that there was a sequence of 13 PAHs at Phen > FA > Pyr > Chr > Fl > An > BaA > BbFA > BghiP > IcdP > BkFA > BaP > DahA and the sum of these PAHs is 36.01 ± 10.85 ng/m³ in gas phase. FL, Phen, FA, Pyr, and Chr were the dominant PAHs in gas phase in the city. They contributed 90% of total PAHs in the gas phase. Proportion of measured PAHs with three, four, five, and six rings to total PAHs was 53%, 42%, 3%, and 2%, respectively. The highest concentration of ΣPAHs (the sum of 13 PAHs) occurred in the wintertime and the lowest was in the summer. This investigation suggested that traffic, wood combustion, and metal scrap burn emissions were dominant sources of the concentrations of PAHs in six city zones compared with coal burning and industry emissions. Further, the traffic emission sources of PAHs in the city were attributed mostly to gasoline-powered vehicles compared with diesel-powered vehicles. It was revealed that the seasonal changes in PAHs in the city depended on different source types. Metal scrap burn was found to be the major source of PAHs during the autumn, while the PAH levels in the atmosphere for winter and spring seasons were mainly influenced by wood and biomass combustion. Comparisons of PAHs among different city zones and with several other cities worldwide were also made and discussed.