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81.
陈辉 《林业劳动安全》2011,24(4):26-27,30
介绍了钢丝绳的基本结构,提出了钢丝绳的选用原则,对钢丝绳的安全使用提出了指导性的建议。  相似文献   
82.
喷水金属丝网除尘效率与阻力关系的实验研究   总被引:1,自引:1,他引:0  
仅依靠金属丝网的过滤作用除尘,其效率非常低,若与喷水结合,效率将大大提高。设计高效喷水金属丝网过滤装置的关键是确定其除尘效率。影响喷水金属丝网除尘效率的因素非常复杂,故直接由这些参数设计计算喷水金属丝网除尘效率是非常困难的,有时甚至是不可能的。阻力测试计算简单,采用量纲分析、实验研究、回归分析相结合的方法,给出了喷水金属丝网除尘效率与阻力关系式,根据阻力关系式间接计算出效率,并可简化设计程序,促进该技术的推广应用。  相似文献   
83.
Atmospheric mixing ratios of carbonyl sulfide (COS) in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations (R2 > 0.66) were found between COS and CO during the periods from May to June and from October to March, with slopes (ΔCOS/ΔCO) of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios.  相似文献   
84.
Atmospheric mixing ratios of carbonyl sulfide(COS) in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations(R2 0.66) were found between COS and CO during the periods from May to June and from October to March, with slopes(ΔCOS/ΔCO) of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios.  相似文献   
85.
In this work a novel anode configuration consisting of an iron mesh double layer is proposed for the electrochemical treatment of wastewater. The removal of Reactive Black 5 dye(RB5) from synthetic contaminated water was used as a model system. At a constant anode surface area, identical process operating parameters and batch process mode, the iron mesh double layer electrode showed better performance compared to the conventional single layer iron mesh. The double layer electrode was characterized by RB5 and chemical oxygen demand(COD) removal efficiency of 98.2% and 97.7%, respectively, kinetic rate constant of 0.0385/min, diffusion coefficient of 4.9 × 10~(-5)cm~2/sec and electrical energy consumption of 20.53 kWh/kgdye removed. In the continuous flow system, the optimum conditions suggested by Response Surface Methodology(RSM) are: initial solution p H of 6.29,current density of 1.6 m A/cm~2, electrolyte dose of 0.15 g/L and flow rate of 11.47 m L/min which resulted in an RB5 removal efficiency of 81.62%.  相似文献   
86.
There is an increasing need and interest in including indicators of landscape fragmentation in monitoring systems of sustainable landscape management. Landscape fragmentation due to transportation infrastructure and urban development threatens human and environmental well-being by noise and pollution from traffic, reducing the size and viability of wildlife populations, facilitating the spread of invasive species, and impairing the scenic and recreational qualities of the landscape. This paper provides the rationale, method, and data for including landscape fragmentation in monitoring systems, using as an example the Swiss Monitoring System of Sustainable Development (Monet). We defined and compared four levels of fragmentation analysis, or fragmentation geometries (FGs), each based on different fragmenting elements, e.g., only anthropogenic, or combinations of anthropogenic and natural elements. As each FG has specific strengths and weaknesses, the most appropriate choice of FG depends on the context and objectives of a study. We present data on the current degree of landscape fragmentation for the five ecoregions and 26 cantons in Switzerland for all four FGs. Our results show that the degree of landscape fragmentation as quantified by the effective mesh size method is strongly supported by the postulates and indicator selection criteria of Monet, and we identify the most suitable FG focusing on the land area below 2100 m (e.g., excluding lakes) and allowing for an equitable comparison of fragmentation degrees among regions that differ in area covered by lakes and high mountains. For a more detailed analysis of landscape fragmentation in the context of environmental impact assessments and strategic environmental assessments, a combination of all four FGs may provide a more informative tool than any single FG.  相似文献   
87.
采用聚乙烯醇(PVA)对尼龙织布表面涂覆改性,对改性前后织布进行表征并进行纯水通量测试,随后以牛血清蛋白(BSA)模拟污染物测试尼龙织布改性前后的抗污染性能,并对改性后的织布进行溶解性有机碳(DOC)浸出实验.改性过程中,优选3%涂覆浓度和250μm涂层厚度,改性后织布的纯水通量值约提高85.0%,对BSA的截留率由6.0%±0.5%上升至7.2%±0.7%,通量恢复率由90.0%提高到96.1%,可逆污染比重上升,不可逆污染比重下降,污染形式主要表现为可逆污染.为避免改性尼龙织布应用于厌氧氨氧化-膜生物反应器(Anammox-MBR)时对厌氧氨氧化反应产生不可逆危害,提出应对制备完成的改性尼龙织布进行为期3d及以上的静态清水浸泡或动态浸出处理.  相似文献   
88.
焊丝行业是高耗能行业,同时也是污染物产排大户。以"煤改燃"技术在天津y焊丝有限公司的实施为案例,简述该技术实施后的节能减排效果,以2014年为例,分别实现SO_2、NO_x、烟尘和废渣减排4.01,24.63,2.02,1252 t;且节约能源消费500多万元,该技术的应用具有显著的环境效益、社会效益和经济效益。  相似文献   
89.
选取钢丝绳行业比较发达的某乡镇为研究区域,对其地区周边土壤及农产品的污染状况进行了野外调查和实验分析研究。结果表明:(1)土壤中铅、锌的含量均有不同程度的污染。(2)土壤中重金属含量与废水灌溉方式有关。(3)废水灌溉的农产品均有不同程度的污染。(4)重金属主要富集在农产品的根部,果实中富集的量很少。  相似文献   
90.
本文基于煤矿安全规程要求,通过对煤矿提升钢丝绳的现状分析和钢丝绳电脑探伤仪的简要介绍及其在晋城矿区的应用实践,从技术研究的角度,提出保证钢丝绳运行安全的解决方案。  相似文献   
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