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301.
302.
柴豫申 《安全.健康和环境》2010,10(6):32-33
近年来,随着高含硫原油加工量的增多,石油化工企业硫化氢中毒事故频发,引起了整个行业的高度重视。针对硫化氢的应急防范,各企业不断加大投入,配置报警仪、防护器具,细化应急预案和管理规定。但在实施过程中也产生了许多误区,本文对几个带有普遍性的问题逐一分析,并提出整改建议。 相似文献
303.
太湖地区太阳辐射与水温的变化特征及其对叶绿素a的影响 总被引:8,自引:1,他引:7
基于中国科学院太湖湖泊生态系统研究站1993年以来的常规监测资料,利用比较与数理统计相关分析方法对太湖地区的太阳辐射和水温变化特征及其对水体叶绿索a浓度的影响进行分析.结果显示,太湖地区太阳总辐射、光合有效辐射、光合有效辐射占总辐射的比例及水温总体上都呈上升的趋势.其中,光合有效辐射的增长速率大于总辐射的增长速率,年际水温增长率春季秋季>夏季.太阳辐射及水温的年内变化呈夏季大,春秋季次之,冬季最小的特征.此外,太阳辐射和水温与叶绿素a呈显著正相关关系(P<0.01),太阳辐射特别是光合有效辐射和水温的增加为藻类的大量生长和水华暴发提供了良好的物理条件,太湖蓝藻水华初始暴发时间有逐年前移的趋势且水华持续时间逐年增加. 相似文献
304.
An overview of reclaimed water reuse in China 总被引:15,自引:1,他引:14
China is facing severe water problems including scarcity and pollution which are now becoming key factors restricting developments. Creating an alternative water resource and reducing effluent discharges, water reuse has been recognized as an integral part of water and wastewater management scheme in China. The government has launched nationwide efforts to optimize the benefits of utilizing reclaimed water. This article reviewed the water reuse activities in China, including: (1) application history and current status; (2) potentials of reclaimed water reuse; (3) laws, policies and regulations governing reclaimed water reuse; (4) risks associated with reclaimed water reuse; (5) issues in reclaimed water reuse. Reclaimed water in Beijing and Tianjin were given as examples. Suggestions for improving the efficiencies of reusing urban wastewater were advanced. Being the largest user of reclaimed wastewater in the world, China's experience can benefit the development of water reuse in other regions. 相似文献
305.
N doped Ti02 films were deposited by direct current pulse magnetron sputtering system at room temperature. The influence of 02 flow rate on the crystal structure of deposited films was studied by Stylus profilometer, X-ray photoelectron spectroscopy, and X-ray diffractometer. The results indicate that the 02 flow rate strongly controls the growth behavior and crystal structure of N doped Ti02 film. It is found that N element mainly exists as substitutional doped state and the chemical stiochiometry is near to TiO1.68±0.06N0.11±0.01 for all film samples. N doped Ti02 film deposited with 2 sccm (standard-state cubic centimeter per minute) 02 flow rate is amorphous structure with high growth rate, which contains both anatase phase and rutile phase crystal nucleuses. In this case, the film displays the mix-phase of anatase and rutile after annealing treatment. While N doped Ti02 film deposited with 12 cm3/min 02 flow rate displays anatase phase before and after annealing treatment. And it should be noticed that no TiN phase appears for all samples before and after annealing treatment. 相似文献
306.
Ziyang Lou Bernd Bilitewski Nanwen Zhu Xiaoli Chai Bing Li Youcai Zhao Peter Otieno 《环境科学学报(英文版)》2015
As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission (GHG), and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment (LCA). Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO2-equivalent (CO2-eq.), 4.43 kg SO2-eq., 4.88 kg NO3−-eq., and 3509 m3 water per ton tourist waste were found to be released in terms of global warming (GW), acidification (AC), nutrient enrichment (NE) and spoiled groundwater resources (SGWR), respectively. The total GHG emission was around 3499 ton CO2-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO2-eq., and CH4, CO and other hydrocarbons (HC) were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton CO2-eq. savings could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective. 相似文献
307.
2020年中国地震局开展了全国公众防震减灾知识普及和科普满意度抽样调查,结果显示,17.1%的受访者具备防震减灾素养,与2018年中国公民科学素质调查结果相比较,公众防震减灾素养水平的区域分布有明显不一样的规律,公众防震减灾素养水平与区域经济发展水平之间没有明显的相关性,区域地震灾害程度和个人地震经历对公众防震减灾素养水平有显著的影响。防震减灾素养水平在城乡、性别、受教育水平等不同群体中的差别,和中国公民科学素质调查结果基本一致,受教育水平对防震减灾素养水平影响最大。在不同年龄群体中的差别则和中国公民科学素质调查结果不同,显示出独特的规律。在防震减灾科普工作中,需要重视公众防震减灾素养水平的这些特点,采取有针对性的措施来提升科普效率。 相似文献
308.
A sound scientific understanding of the factors affecting the environment is essential to guarantee the sustainable development of the world's economic and societal activities.Many environmental issues,such as air quality and climate change are intimately linked to atmospheric chemistry and physics,therefore research in these areas is of tremendous importance.Both anthropogenic and biogenic emissions contribute greatly to the chemical composition of the atmosphere.Even though the atmosphere is a self-cleaning system through its photochemically-driven reactions,the hazardous direct impacts of primary and secondary pollutants on human health and ecosystems are observable and have been evidenced on different scales from local to global (e.g.ozone hole,climate change,air quality…).The chemical processing of the species present in the atmosphere is one of the most important players in driving the evolution of the atmosphere. 相似文献
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310.
本文探讨了生态系统和物种多样性所面临的威胁,指出目前物种灭绝的速度在加快,濒危物种在增多,生物多样性保护的重点应是濒危物种。并分析了生物多样性丧失的原因,认为人口过快增加是生物多样性危机的主要根源 相似文献