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101.
介绍ISM制订的背景,其目的是要加强执行有关海上安全、海洋防污染和海员培训等国际公约。ISM的内容也作了简要说明。香港明华船务公司请中国船级社协助以实施ISM规则。该文较为详细地介绍了制订各种规章制度和文件,以及在公司和船上落实ISM的措施。经过两年努力,终于取得符合ISM的证书,但是要完全达到ISM的要求,仍有许多工作要做。 相似文献
102.
Li Li Wei Lai Jinguo Pu Hengqin Mo Dongjue Dai Guilin Wu Shihuai Deng 《环境科学学报(英文版)》2018,30(7):281-293
PM_(2.5) aerosol samples were collected over 12 hr and 24 hr intervals in an inland background area, Gongga Mountain National Nature Reserve(hereafter shortened to Gongga), during the summer of 2011. Polar organic tracers, inorganic ions and meteorological data were measured. The purpose of this work was to investigate the variation patterns, formation and sources of the secondary organic aerosol tracers in the studied atmosphere. The average concentrations of isoprene oxidation products, α-pinene oxidation products, β-caryophyllinic acid, sugars, sugar alcohols and anhydrosugars were 88.6 ± 106.1, 3.6 ± 5.7,0.13 ± 0.30, 13.6 ± 13.1, 31.9 ± 31.4 and 14.8 ± 10.7 ng/m3 respectively in all aerosol samples.The aged α-pinene second organic aerosol(SOA) tracers(i.e., 3-hydroxyglutraric acid(3 HGA), 3-hydroxy-2,2-dimethylglutaric acid(HDMGA), 3-acetylpentandioic acid(APDA) and 3-methyl-1,2,3-butanetricarboxylic acid(MBTCA)) correlated significantly with each other in the 24 hr PM2.5 aerosol samples, indicating that OH· is the major factor controlling the formation of these α-pinene SOA tracers. Using the positive matrix factorization(PMF) model and the tracer-based source apportionment method, we calculated that isoprene oxidation products, α-pinene oxidation products, sesquiterpene oxidation products, biomass burning, fungi spores and anthropogenic SOA accounted for 21.9% ± 5.5%, 8.4% ± 2.1%, 3.0% ± 0.7%, 5.2% ± 5.3%, 5.0% ± 6.2% and 31.4% ± 7.8% of organic carbon respectively during the sampling period. 相似文献
103.
104.
Yi-Bo Li Wan-Fen Pu Jiang-Yu Zhao Qi-Ning Zhao Lin Sun Fa-Yang Jin 《International Journal of Green Energy》2016,13(2):173-180
This research aimed at determining the variation of reservoir fluid property during the high-pressure air injection process. For this purpose, the forward multiple contact experiment was employed by pressure–volume–temperature (PVT) system to investigate the physical property variation of the crude oil and the complex oxidation reactions. The results show: under the relative low temperature and pressure condition, instead of carbon dioxide, carbon monoxide dominates the products in the air phase. The gas/oil ratio and volume ratio increased due to the generated gas while the viscosity and density achieved a descending trend. The colloid and bitumen in the oil phase reduced by half but the amount of wax achieved a small increase. The low-temperature oxidation and pyrolysis reactions caused the fluctuated change of the different compounds. The amount of light compounds decreased at the beginning and then increased while that of heavy compounds showed the opposite trend. But at last, due to the H/C ratio, the light compounds increased to more than their initial value. 相似文献
105.
Evaluation of atmospheric sources of PCDD/Fs, PCBs and PBDEs around a steel industrial complex in northeast China using passive air samplers 总被引:4,自引:0,他引:4
The concern about emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) from steel industrial parks has increased in the past decades. In this study, polyurethane foam (PUF)-disk based passive air samples were collected in and around a big steel industrial park of Anshan, Northeast China from June 2008 to March 2009. The levels, seasonal variations and potential sources of PCDD/Fs, PCBs and PBDEs in the atmosphere around the steel industrial complex were investigated, and potential contribution of these three groups of persistent organic pollutants (POPs) from iron and steel production was also assessed. The air concentrations of ∑17PCDD/Fs (summer: 0.02-2.77 pg m−3; winter: 0.20-9.79 pg m−3), ∑19PCBs (summer: 23.5-155.8 pg m−3; winter: 14.6-81.3 pg m−3) and ∑13PBDEs (summer: 2.91-10.7 pg m−3; winter: 1.10-3.89 pg m−3) in this targeted industrial park were relatively low in comparison to other studies, which implied that the industrial activities of iron and steel had not resulted in serious contamination to the ambient air in this area. On the whole, the air concentrations of PCDD/Fs in winter were higher than those of summer, whereas the concentrations of PCBs and PBDEs showed opposite trends. The result from principal component analysis indicated that coal combustion might be the main contributor of PCDD/F sources in this area. 相似文献
106.
针对临近杆塔接地网的管道过电压及防护问题,采用CDEGS仿真计算软件建立电力杆塔接地网及临近燃气管道结构模型,研究杆塔与管道间距、土壤电阻率和接地排流线等因素对管道过电压的影响;并提出通过优化电力杆塔接地网外延射线结构降低管道过电压的改造方案。研究结果表明:管道上的雷击过电压受散流间距、土质条件等因素的影响,并基本呈现线性关系;管道增设排流设施后,过电压减小;接地网外延射线结构改造后管道过电压抑制作用明显。研究结果可为实际燃气管道安全防护及电力设计施工提供理论参考。 相似文献
107.
Guiyin?Wang Shirong?ZhangEmail author Luoyi?Xiao Qinmei?Zhong Linxian?Li Guangrong?Xu Ouping?Deng Yulin?Pu 《Environmental science and pollution research international》2017,24(20):16618-16630
Anthropogenic activities could result in increasing concentrations of heavy metals in soil and deteriorating in soil environmental quality. Topsoil samples from a typical industrial area, Shiting River Valley, Sichuan, Southwest China, were collected and determined for the concentrations of Cu, Zn, Cr, Cd, As, and Hg. The mean concentrations of these metals were lower than the national threshold values, but were slightly higher than their corresponding background values, indicating enrichment of these metals in soils in the valley, especially for Cu, Zn, and Hg. The topsoils in this area demonstrated moderate pollution and low potential ecological risk. Principal component analysis coupled with cluster analysis was applied to analyze the data and identified possible sources of these heavy metals; the results showed that soil Cd, Hg, As, Cu, and Zn were predominantly controlled by human activities, whereas Cr was mainly from the parent material. The spatial distribution of the heavy metals varied distinctly and was closely correlated to local anthropogenic activities. Furthermore, the concentrations of heavy metals in the industrial land demonstrated relatively higher levels than those of other land use patterns. Soil metal concentrations decreased with the distance increase from the traffic highway (0–1.0 km) and water system (0–2.0 km). Additionally, soil properties, especially pH and soil organic matter, were found to be important factors in the distribution and composition of metals. 相似文献
108.
Yong-Jun Zhao Pu Cheng Xi Pei Hui Zhang Cheng Yan Shou-Bing Wang 《Environmental science and pollution research international》2013,20(7):4886-4894
The performance and temporal variation of hybrid vertical-subsurface flow constructed wetlands (VFCWs) in response to two-stage combinations of vertical upflow (VUF) and vertical downflow (VDF) were analyzed in this research. The results of high carbon (C) treatment and high nitrogen (N) treatment were similar. The Lythrum salicaria treatment showed higher removal efficiency than CWs planted with Acorus calamus. Under high C- and N-loading treatments, the optimum two-stage combination was VDF-VUF VFCWs planted with A. calamus. Furthermore, the highest nutrient removal efficiencies were achieved in late summer (July and August) and early autumn (September). The chemical oxygen demand and total nitrogen removal efficiencies were significantly affected (P?<?0.05) by season, system, and wetland plant. 相似文献
109.
Altitude dependence of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in surface soil from Tibetan Plateau, China 总被引:5,自引:0,他引:5
Pu Wang Qinghua Zhang Yawei Wang Thanh Wang Xiaomin Li Yingming Li Lei Ding Guibin Jiang 《Chemosphere》2009,76(11):1498-1504
Remote mountain areas besides high latitude regions are beginning to receive increased attention in studying the transport and behavior of persistent organic pollutants (POPs). In the present work, surface soil samples were collected from the Tibetan Plateau, the highest plateau in the world which includes the northern slope of Mt. Qomolangma, to investigate the levels and trends of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) along the altitudinal gradient. The average PCB and PBDE concentrations were 185.6 ng kg−1 dry weight (dw) (range 47.1–422.6 ng kg−1 dw) and 11.1 ng kg−1 dw (range 4.3–34.9 ng kg−1 dw), respectively. Regression analysis between the log-transformed TOC-normalized concentrations and the altitudes of the sampling sites showed two opposite trends with regard to altitude dependence: negative relationship with altitude below about 4500 m followed by a positive altitude dependence above this point. Considering minimum anthropogenic activities and very sparse precipitation in the north of Himalayas, the trends above 4500 m imply that the significant altitude dependence of these two groups of POPs were irrespective of pollution sources, but could be predicted by the global distillation effect involving cold condensation in high altitude mountain areas. Increasing levels of heavier congeners were found in higher altitude sites, although the lighter congeners were the main contributors to the total amount, suggesting that less volatile congeners seem to become enriched easier than those more volatile at higher altitudes in this region. 相似文献
110.
Primitive e-waste dismantling activities have been of increasing concern due to serious environmental and human health problems, and therefore authorities in China have strengthened the regulations on illegal e-waste recycling activities. In this work, we used rice hull as a passive sampler and investigated temporal trends of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) in areas near e-waste recycling sites after the stricter regulations. Furthermore, the distribution patterns and composition profiles of these contaminants were also discussed. The average concentrations of the three groups of persistent organic pollutants (POPs) in rice hulls have markedly decreased during the period of 2005-2009. Specifically, from 12.9 (average value in 2005) to 0.37 pg WHO-TEQ/g (dry weight, dw) (in 2009) for PCDD/Fs, 47.6 (2005) to 7.10 ng g−1 dw (2009) for PCBs, and 2.51 (2005) to 0.89 ng g−1, dw (2009) for PBDEs. The significant decrease of combustion markers 2,3,4,7,8-PeCDF, 1,2,3,6,7,8HxCDF and PCB126, and the PCDD/PCDF ratio from 1:9 (2005) to 7:3 (2009) is likely a result of stricter regulations on open combustion activities. This study suggests that stricter control measures, strengthened laws and regulations and more environmental friendly techniques could be effective measures in reducing the release and formation of related POPs in typical e-waste dismantling sites, and these measures could further improve the quality of the environment and health of the local inhabitants. 相似文献