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11.
环境空气质量功能区的划分对沈阳市的大气污染物总量控制、沈阳市结构性污染调整及制定环境管理政策和法规都具有重要的指导意义.沈阳市环境空气质量按功能区达标有一定难度,具体来讲,二类区达标难度最大,一类区相对容易,三类区是工业区,基本上就地改造即可达标.  相似文献   
12.
Differentiation of nitrous oxide emission factors for agricultural soils   总被引:3,自引:0,他引:3  
Nitrous oxide (N2O) direct soil emissions from agriculture are often estimated using the default IPCC emission factor (EF) of 1%. However, a large variation in EFs exists due to differences in environment, crops and management. We developed an approach to determine N2O EFs that depend on N-input sources and environmental factors. The starting point of the method was a monitoring study in which an EF of 1% was found. The conditions of this experiment were set as the reference from which the effects of 16 sources of N input, three soil types, two land-use types and annual precipitation on the N2O EF were estimated. The derived EF inference scheme performed on average better than the default IPCC EF. The use of differentiated EFs, including different regional conditions, allows accounting for the effects of more mitigation measures and offers European countries a possibility to use a Tier 2 approach.  相似文献   
13.
空间结构展示了一个国家建筑科技新成果和实力 ,由于建筑业的特殊性 ,其安全性备受关注。笔者阐述了空间结构的施工特点以及施工中人为错误的成因和对工程的影响 ,通过对人为错误与建筑风险造价关系的分析 ,提出了控制人为错误的对策为 :适当提高结构设计可靠度水平和加强施工过程的管理 ,减少人为错误的发生 ,对遏制工程质量事故具有指导意义。  相似文献   
14.
Ali/(Ca + Mg) molar ratio in soil water has been used as an indicator to the effects of acid deposition on terrestrial ecosystems. However, the main factors controlling this ratio have not been well documented in southern and southwestern China. In this study, we presented the variation in inorganic aluminum (Ali) and Ali/(Ca + Mg) molar ratio in different sites and soil horizons based on two to three years monitoring data, and evaluated the main factors controlling Ali/(Ca + Mg) molar ratio using principle component analysis (PCA) and partial least square (PLS) regression. Monitoring data showed although Ali/(Ca + Mg) molar ratios in most soil water were lower than assumed critical 1.0, higher molar ratios were found in some soil water at TSP and LXH site. Besides acid loading, both soil properties and soil water chemistry affected the value of Ali/(Ca + Mg) molar ratio in soil water. Partial least square (PLS) indicated that they had different relative importance in different soil horizons. In A-horizon, soil aluminum saturation (AlS) had higher influence on Ali/(Ca + Mg) molar ratio than soil water chemistry did; higher soil aluminum saturation (AlS) led to higher Ali/(Ca + Mg) molar ratio in soil water. In the deeper horizons (i.e., B1-, B2- and BC-horizon), inorganic aluminum (Ali) in soil water had more and more important role in regulating Ali/(Ca + Mg) molar ratio. On regional scale, soil aluminum saturation (AlS) as well as cation exchange capacity (CEC) was the dominant factor controlling Ali/(Ca + Mg) molar ratio. This should be paid enough attention on when making regional acid rain control policy in China.  相似文献   
15.
以现场注水试验和实验室实验结果为依据,分析并讨论了目前研究甚少而又对注水防尘实施,特别是在软煤层综放工作面实施很重要的工艺问题,提出了适宜的钻孔、封孔、润湿效果考察方法以及表面活性剂应用中的浓度选择、种类选择和应用的必要性评价方法  相似文献   
16.
辗环是生产无接缝环圈的先进技术之一,此文分析了辗环过程及变形,建立了径向辗环变形过程的数学模型,以此为据制定的程序。使φ500型齿轮毛坯辗扩机实现了在线预测智能型尺寸控制。此控制系统投资少、结构简单、性能稳定可靠,在实际生产中使坯件尺寸精度达到:△φ±1mm,保证了稳定生产。  相似文献   
17.
新沂河污水资源化生态工程是以蔷薇河送清水工程为依托 ,将新沂河北偏泓作为排污专道 ,排污专线可构建成为五级河道稳定塘。其技术路线是控源导流 ,清污分流 ,通过河道稳定塘来自然降解城市污水。本文以科学的预测数据论证了工程的可行性。  相似文献   
18.
我国油站量油技术与油气排放浅析   总被引:1,自引:0,他引:1  
论述工加油站油气排放控制与运油罐车、地下储罐量油方式的关系,概述了我国加油站量油方式的现状,以及人工测量和液位仪密闭自动测量两种量油方式。综述了电容式液位仪、超声波液位仪和磁致伸缩式液位仪的量油原理、特点及发展趋势,重点介绍了磁致伸缩技术,并结合汽油流转过程中油气密闭性控制的重要性及储油罐的管理要求,展望了未来加油站量油方式的技术发展趋势。  相似文献   
19.
学术期刊编辑工作与其它出版物的编辑一样,要遵循具体的编辑程序。充分揭示和反映学术期刊编辑活动的规律、原则、基本特点及其功能,是从事学术期刊编辑工作的同仁始终要追求的目标。学术期刊的整个编辑活动要体现其创造性。  相似文献   
20.
Review on fate of chlorine during thermal processing of solid wastes   总被引:1,自引:0,他引:1  
Chlorine(Cl) is extensively present in solid wastes, causing significant problems during the thermal conversion of waste to energy or fuels, by combustion, gasification or pyrolysis.This paper introduces the analytical methods for determining the Cl content in solid materials and presents the concentrations of Cl in various types of wastes, as reported in literature. Then, it provides a comprehensive analysis on the Cl emission behavior and Cl species formed during the thermal processing of the inorganic and organic Cl sources. The challenges resulted from the reactions between the formed Cl species and the ferrous metals, the heavy metals and the organic matters are summarized and discussed, e.g., high temperature corrosion, heavy metal evaporation and dioxin formation. The quality degradation of products(oil, char and syngas) by Cl is analyzed. Finally, the available controlling methods of Cl emission, including pre-treatment(water washing, sorting,microwave irradiation and stepwise pyrolysis) and in-furnace(absorbents, co-treatment and catalysts) methods are assessed.  相似文献   
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