Concentration and source identification of polycyclic aromatic hydrocarbons and phthalic acid esters in the surface water of the Yangtze River Delta, China

The pollution from polycyclic aromatic hydrocarbons (PAHs) and phthalic acid esters (PAEs) in the surface water of the rapidly urbanized Yangtze River Delta region was investigated. Fourteen surface water samples were collected in June 2010. Water samples were liquid-liquid extracted using methylene chloride and analyzed by gas chromatography-mass spectrometry. Concentrations of PAHs and PAEs ranged 12.9-638.1 ng/L and 61-28550 ng/L, respectively. Fluoranthene, naphthalene, pyrene, phenanthrene, di-2-ethylhexyl phthalate, and di-n-butyl phthalate were the most abundant compounds in the samples. The water samples were moderately polluted with benzo[a]pyrene according to China's environmental quality standard for surface water. The two highest concentrations of PAHs and PAEs occurred in samples from Taihu Lake, Wuxi City and the western section of Yangchenghu Lake. Potential sources of pollution at S7 were petroleum combustion and the plastics industry, and at Yangchenghu Lake were petroleum combustion and domestic waste. Pollution in samples from the Beijing-Hangzhou Grand Canal originated from diesel engines. There were no obvious sources of pollution for the other water samples. These results can be used as reference levels for future monitoring programs of pollution from PAHs and PAEs.     

火山灾害及其监测预防

本文阐明火山灾害是一种重大自然灾害,给人民生命财产造成严重损失。文中指出当前火山活动进入新的活跃期,提出我国火山灾害的潜在危险。我国许多休眠火山区,正在成为新的经济开发区和旅游疗养、开发地热和建材资源的新兴城镇,人口迅速增加,经济蓬勃发展。但还没有采取有效的火山监测研究和防灾措施。作者建议,应把火山监测研究纳入政府防灾日程,制定规划,拨出专款,把防御火山灾害同国土开发,经济建设结合起来。     

洪水作用下村镇住宅的力学响应试验研究

针对洪水作用下村镇住宅的反应,通过建立房屋模型,研究不同洪水水力条件下,村镇住宅所受的洪水压力、应变等分布规律,并分析了不同房屋结构以及基础对抵抗洪水作用的影响,初步得到了洪水作用下村镇住宅的破坏机理。     

Impact of alkyl methacrylate–maleic anhydride–alkyl methacrylate terpolymers as cold flow improver on crystallization behavior of diesel fuel

Alkyl methacrylate–maleic anhydride–alkyl methacrylate terpolymers (MR₁–MA–MR₂) is one of the widely used cold flow improver. In order to develop more efficient MR₁–MA–MR₂, it is necessary to study the crystallization behavior of n-alkanes when adding MR₁–MA–MR₂ into diesel fuel. In this paper, MR₁–MA–MR₂ is prepared by the reaction of long-chain alkyl methacrylate (MR₁), maleic anhydride (MA), and short alkyl methacrylate (MR₂). The diesel fuel before and after adding MR₁–MA–MR₂ is in situ filtrated at its cold filter plugging point (CFPP) in a manual CFPP apparatus. Extensive measurements of composition variation of n-alkanes are done by gas chromatograph and the results are compared. The experimental results show that after adding MR₁–MA–MR₂, the concentration distribution of n-alkanes in the filtrate is wide and arranges from 8 to 26, and mainly centralizes from 10 to 19. For the precipitate, the concentration distribution of n-alkanes gets richer in the lighter n-alkanes and poorer in the heavier n-alkanes. The concentration distribution of n-alkanes in the crystal solid shows a decreasing trend, especially with high carbon number n-alkanes (heavier than C₂₀). About 60–70% of the residual crystal solid is composed of non-paraffins such as isoparaffin, naphthene and other components. Crystallinities of n-alkanes show a slow decrease trend from C₈ to C₂₀. When the carbon number n-alkanes are heavier than C₂₀, the crystallinities of n-alkanes begin to sharply reduce with an increase of carbon number. The largest decline of crystallinity is C₂₆ n-alkane from 38.39% to 7.90%.     

甲醇燃料车尾气净化催化剂的研究(Ⅰ)──单组分催化剂对甲醇的深度氧化

利用色谱－微反联用技术对甲醇深度氧化进行了研究。结果表明：甲醇在所有催化剂上氧化时均产生副产物甲醛及甲酸甲酯;非贵金属氧化物催化剂以Ｃｕ－Ｏ／ｒ－Ａｌ２Ｏ３的活性最优,其最佳负载量为１０％－２０％,不同的制备方法中以均匀沉淀法制备的催化剂最好;贵金属催化剂中Ａｇ／ｒ－Ａｌ２Ｏ３的活性较好,其甲醇氧化的Ｔ５０,Ｔ９５分别只有１３５℃和１９０℃,而且伴生的甲醛及甲酸甲酯浓度也较低。不同催化剂的活性与其     

数字式光学测尘仪对不同呼吸性粉尘浓度转换系数的求取

本文论述了用BY-1型呼吸性粉尘标定采样器,在云南锡业公司矿山和冶炼厂现场测定、求取P-5L_2型和TM型光学测尘仪的读数与呼吸性粉尘(空气动力学直径:<7.07μm和<10μm)质量浓度转换系数(K)的方法和结果.研究表明,由深色矿物组成的粉尘,其K值大于由浅色矿物组成的粉尘的K值.P-5L_2型光学测尘仪间的测尘误差85％以上在±10％以内,平均为±6.68％.     

Habitat type determines herbivory controls over CO2 fluxes in a warmer Arctic

High-latitude ecosystems store large amounts of carbon (C); however, the C storage of these ecosystems is under threat from both climate warming and increased levels of herbivory. In this study we examined the combined role of herbivores and climate warming as drivers of CO2 fluxes in two typical high-latitude habitats (mesic heath and wet meadow). We hypothesized that both herbivory and climate warming would reduce the C sink strength of Arctic tundra through their combined effects on plant biomass and gross ecosystem photosynthesis and on decomposition rates and the abiotic environment. To test this hypothesis we employed experimental warming (via International Tundra Experiment [ITEX] chambers) and grazing (via captive Barnacle Geese) in a three-year factorial field experiment. Ecosystem CO2 fluxes (net ecosystem exchange of CO2, ecosystem respiration, and gross ecosystem photosynthesis) were measured in all treatments at varying intensity over the three growing seasons to capture the impact of the treatments on a range of temporal scales (diurnal, seasonal, and interannual). Grazing and warming treatments had markedly different effects on CO2 fluxes in the two tundra habitats. Grazing caused a strong reduction in CO2 assimilation in the wet meadow, while warming reduced CO2 efflux from the mesic heath. Treatment effects on net ecosystem exchange largely derived from the modification of gross ecosystem photosynthesis rather than ecosystem respiration. In this study we have demonstrated that on the habitat scale, grazing by geese is a strong driver of net ecosystem exchange of CO2, with the potential to reduce the CO2 sink strength of Arctic ecosystems. Our results highlight that the large reduction in plant biomass due to goose grazing in the Arctic noted in several studies can alter the C balance of wet tundra ecosystems. We conclude that herbivory will modulate direct climate warming responses of Arctic tundra with implications for the ecosystem C balance; however, the magnitude and direction of the response will be habitat-specific.     

Ochrobactrum anthropi 对苯胺的降解特性

利用自行筛选驯经的苯胺降解菌人苍白杆菌对影响胺降解的各种主要因素进行了研究。发现降解菌在３５℃,ＰＨ．下及苯胺初始浓度２００－８００ｍｇ／Ｌ的范围内保持高活必在最大降解速率率达到１０．０５ｍｇ．（Ｌ．ｈ）＾－１。     

CTMAB-膨润土去除水中有机物的性能及机理

用溴化十六烷基三甲铵（CTMAB）改性膨润土,研究了CTMAB膨润土去除水中苯、甲苯、乙苯、硝基苯、苯胺、苯酚、对硝基苯酚的性能、机理及影响因素。结果表明,CTMAB-膨润土去除水中有机物的能力远大于原土;CTMAB-膨润土对苯、甲苯、乙苯的等温吸附曲线呈线性;对水中苯酚、对硝基苯酚的等温吸附曲线呈非线性;对苯胺、硝基苯的等温吸附曲线基本呈线性。CTMAB-膨润土吸附水中有机物的性能及机理与有机物的水溶性或辛醇－水分配系数有关。     

天津地区土壤多环芳烃在剖面中的纵向分布特征

在天津市北部山区、中部农田和东南部油田采油作业区分别采集了土壤样品 ,研究了土壤中多环芳烃 (PAHs)的纵向分布特征 ,并对土壤中多环芳烃的来源进行了分析 .结果表明 ,PAHs含量峰值一般位于土壤表层或次表层 ,并随着土壤剖面的加深而减少 .农田菜地土壤PAHs在 4 0cm深处含量仍然较高 ,而油田仅表层 3cm富集PAHs ,这与耕作土壤表层常受到人为扰动有关 .与高环物质相比 ,低环物质更容易向下迁移 .土壤中有机碳的含量、土壤的性质以及土壤的粒度均是影响PAHs迁移的重要因素 .山区和菜地土壤中PAHs主要来自燃烧源 ,而油田则显示为石油源和燃烧源的混合源 .