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491.
段乔红 《安全.健康和环境》2022,22(1):53-55
剖析了国企安全生产中发挥党组织作用的现实差距,提出了安全生产中发挥党组织作用的路径措施:深化政治建设提升引领力,抓好有效覆盖提升组织力,促进深度融合提升推动力,加强群团作用提升凝聚力,强化监督考评提升驱动力。充分发挥党组织作用,使"根"从基层扎牢、"魂"从堡垒筑强,就能本固基稳,扛起安全生产"泰山之重"的责任,引领保障企业高质量发展和建设世界一流企业行稳致远。 相似文献
492.
Yao Chen Jinhui Li Huabo Duan Zhishi Wang 《Frontiers of Environmental Science & Engineering in China》2011,5(2):167-174
Mechanical waste-processing methods, which combine crushing and separation processes for the recovery of valuable materials,
have been widely applied in waste printed wiring board (PWB) treatment. However, both the high impact toughness and the tensile
and flexural strengths of whole PWB with a laminated structure result in great energy consumption and severe abrasion of the
cutters during multi-level crushing. In addition, the high temperatures occurring in continual crushing probably cause the
decomposition of the polymer matrix. A thermal-crack method using residual steam as the heating medium has been developed
to pre-treat waste PWBs. This treatment reduces the mechanical strength in order to improve the recovery rate of valuable
materials in subsequent mechanical recycling. The changes of the PWBs’ macro-mechanical properties were studied to evaluate
thermal expansion impacts associated with changes in temperature, and the dynamic dislocation micro-structures were observed
to identify the fracture mechanism. The results showed that thermal cracking with steam at the temperature of 500 K can effectively
attenuate the mechanical properties of waste PWBs, by reducing the impact, tensile and flexural strengths respectively, by
59.2%, 49.3% and 51.4%, compared to untreated PWB. Thermal expansion can also facilitate the separation of copper from glass
fiber by reducing peel resistance by 95.4% at 500 K. It was revealed that the flexural fracture was a transverse cracking
caused by concentrated stress when the heating temperature was less than 500 K, and shifted to a vertical cracking after exceeding
500 K. 相似文献
493.
A series of H-SAPO-34 zeolites were synthesized by a hydrothermal method in fluoride media. The as-synthesized H-SAPO-34 zeolites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 physisorption, temperature-programmed desorption of NH3 (NH3-TPD) and nuclear magnetic resonance (NMR) measurements. The results showed that a certain concentration of F− anions promoted the nucleation and crystallization of H-SAPO-34. The H-SAPO-34 synthesized in the fluoride media showed high crystallinity, uniform particle size distribution, large specific surface area and pore volume, and enhanced acidity. Therefore, Cu/SAPO-34 based on the fluoride-assisted zeolite showed a broadened temperature window for the selective catalytic reduction of NO by NH3 (NH3-SCR) reaction due to the enhanced acidity of the zeolite and the improved dispersion of copper species. 相似文献
494.
495.
Ke Xiao Jianping Deng Li Zeng Tao Guo Yan Gong Bo Yang Xu Zhao Huabo Duan 《环境科学学报(英文版)》2019,31(1):98-104
Electrolysis is a promising technology to improve sludge dewaterability efficiently with negligible environmental impact. To intensify the electrolytic efficiency, the effect of electrolytes (NaCl, Na2SO4, NaNO3, and NaClO4) on electrolysis pretreatment of municipal sludge and its mechanisms was investigated using Ti/PbO2 electrodes. The electrolytes, which enhanced the production of oxidative radicals, showed a significant synergetic effect in reducing the capillary suction time (CST) of sludge. NaCl was distinguished from the other electrolytes since it formed a large amount of active chlorine species, which oxidized the sludge cells to improve the sludge dewaterability. The surface morphologies as well as the soluble proteins and polysaccharides were analyzed to unravel the underlying mechanisms of sludge dewaterability. Additionally, an economic assessment showed that NaCl addition in the electrolysis pretreatment can be a suitable technique for enhancing municipal sludge dewaterability. 相似文献
496.
用稳态法确定中国土壤的硫沉降和氮沉降临界负荷 总被引:16,自引:4,他引:16
'在地理信息系统支持下,用稳态法确定了中国土壤的硫沉降临界负荷和氮沉降临界负荷.中国硫沉降临界负荷最小[<0.3 g·(m2·a)-1]的地区主要分布在东北的大兴安岭、小兴安岭和长白山,青藏高原南部雅鲁藏布江河谷以及云南西南部怒江和澜沧江流域,而酸沉降污染较为严重的富铝土区域,总体上都能够承受0.8~3.2 g·(m2·a)-1的酸沉降.根据硫沉降临界负荷可以将中国大致划分为东南和西北2部分,东南部大部分地区只能接受小于3.2 g·(m2·a)-1的硫沉降,而西北部普遍可以接受大于3.2 g·(m2·a)-1的硫沉降,其分界线基本上与400mm等降水量线重合.与硫沉降临界负荷的分布不同,中国氮沉降临界负荷在总体上呈现自西向东逐渐增加的格局.中国氮沉降临界负荷最低[<1.0 g·(m2·a)-1]的地区分布青藏高原西部和阿拉善高原,而氮沉降临界负荷最高[>4.0 g·(m2·a)-1]的地区则包括东北平原、华北平原、长江中下游平原以及四川盆地等. 相似文献
497.
SO2排放造成的森林损失计算:以湖南省为例 总被引:2,自引:0,他引:2
SO2排放对我国的森林生态系统造成了严重的损害,因而损失计算对于SO2控制具有重要意义,但是目前仍缺乏有效的方法计算不同排放水平下的森林损失.本研究以硫沉降超临界负荷作为计算森林损失的参数,推导了适用于我国硫沉降导致森林损失的剂量-响应函数,并以湖南省为例,以1995为基准年,计算了2000年~2020年高中低3种SO2排放方案下的森林损失.研究结果表明,随着今后湖南省经济和能源消费的增长,森林损失将继续增加.高排放方案下2020年SO2排放将增长1.2倍,但森林损失增长4.3倍,边际损失高于6000元/t.在当前排放水平下对SO2排放进行削减,边际效益达到1500元/t,因此控制SO2具有显著的经济效益.对湖南案例的不确定性分析显示,计算方法有较高的可靠性.研究结果为区域SO2控制策略的优化提供了支持. 相似文献
498.
By developing a GDMOD model to estimate the environmental externalities associated with electricity generation,this project provides a detailed analysis of the damages and costs caused by different pollutants at varying distances from the Mawan Electricity Plant in Shenzhen,China.The major findings of this study can be summarized that(1) environmental damages caused by electricity production are large and are mainly imposed on regions far away from the electricity plant;(2)air pollution is most significant contributor to the totat damages,and SO2,NOx,and particulate matter are the three major pollutants with highest damages;(3)the damages caused per unit of particulate.NOx,and SO2 emissions are much higher than pollution treatment and prevention costs.The research results of this project showed that China needs to have a more effective levy system on SO2,and a more manageable electricity tariff mechanism to internalize the environmental externalities,The results have also implications for pollution control strategies,compensation schemes as well as emission trading arrangements. 相似文献
499.
Submerged membrane bioreactors(SMBR) are widely used in wastewater treatment. The permeability of a membrane declines rapidly because of the formation of a cake layer on the membrane surface. In this paper, a multiple staining protocol was conducted to probe the four major foulants in the cake layer formed on a filtration membrane. Fluorescent images of the foulants were obtained using a confocal laser scanning microscope(CLSM). The three dimensional structure of the cake layer was reconstructed, and the internal flow was calculated using computational fluid dynamics(CFD). Simulation results agreed well with the experimental data on the permeability of the cake layer during filtration and showed better accuracy than the calculation by Kozeny–Carman method. β-D-Glucopyranose polysaccharides and proteins are the two main foulants with relatively large volume fractions, while α-D-glucopyranose polysaccharides and nucleic acids have relatively large specific surface areas. The fast growth of β-D-glucopyranose polysaccharides in the volume fraction is mainly responsible for the increase in cake volume fraction and the decrease in permeability. The specific area, or the aggregation/dispersion of foulants, is less important to its permeability compared to its volume fraction. 相似文献
500.