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201.
煤泥制备活性炭的研究及应用 总被引:1,自引:0,他引:1
以洗煤厂的废料为原料制备活性炭,结果表明,只要其灰分含量小于25%,就可以制备出性能较好的粒状活性炭.活性炭对苯的吸附容量达450mg·g~(-1),对水中对硝基苯酚的饱和吸附容量约为430mg·g~(-1),四氯化碳吸附率约54%,比表面积约1000m~2·g~(-1),碘值700mgI_2·g~(-1),可用于有机溶剂回收、空气与水的净化及作催化剂载体. 相似文献
202.
203.
本文依托2011年江西省环境保护及相关产业基本情况调查,对江西省环境保护产品经营现状进行分析,研究了环境保护产品经营规模、行业分布、质量状况、产值等经营现状,并剖析了江西省环境保护产品经营存在的问题。 相似文献
204.
Blast furnace gas (BF gas) produced in the iron making process is an essential energy resource for a steel making work. As compared with coke oven gas, the caloric value of BF gas is too low to be used alone as fuel in hot stove because of its high concentrations of carbon dioxide and nitrogen. If the carbon dioxide in BF gas could be captured efficiently, it would meet the increasing need of high caloric BF gas, and develop methods to reusing and/or recycling the separated carbon dioxide further. Focused on this, investigations were done with simple evaluation on possible methods of removing carbon dioxide from BF gas and basic experiments on carbon dioxide capture by chemical absorption. The experimental results showed that in 100 minutes, the maximum absorbed doses of carbon dioxide reached 20 g/100 g with ionic liquid as absorbent. 相似文献
205.
我国城市建设用地利用效益评价 总被引:22,自引:1,他引:21
从土地利用的综合效益出发。采用因子分析方法从经济、社会、环境等多角度对现阶段我国各省(区、市)城市建设用地的综合利用效益进行了定量化评价。研究结果显示,土地利用效益偏低的省份为18个,占60%,主要分布在中西部地区,利用效益较高的省份为7个。主要位于东部沿海等地。本研究方法克服了以往单因素评价方法的不足,即片面追求经济总量不一定实现土地资源可持续高效利用。同时,为从空间角度调控土地利用效益提供了一定的政策建议。 相似文献
206.
目的缩短38CrMoAl钢离子渗氮工艺周期。方法在离子渗氮过程中,添加稀土金属镧(La)及稀土镧铈合金(La-Ce)。通过显微硬度仪、光学金相显微镜、扫描电镜及能谱分析仪对于离子氮化层的表面硬度、脆性、微观显微组织、稀土元素含量进行检测分析,并和常规离子渗氮工艺进行对比研究。结果在离子渗氮工艺过程中,添加稀土金属镧(La)及镧铈合金(La-Ce)后,氮化层表面硬度提高约130~200 HV,渗氮速度提高了15%~30%,氮化周期显著缩短。稀土催渗离子渗氮层的脆性均为Ⅰ级,比常规离子渗氮更优异。同时,稀土元素的渗入细化了晶粒,使得渗层氮化物组织致密、呈弥散分布,优化了氮化层的相结构组成。结论稀土元素的加入可以有效提高渗氮层的表面硬度和脆性等级,改善了氮化层性能。同时缩短了离子渗氮工艺周期。 相似文献
207.
Significant iron release from cast iron pipes in water distribution systems (WDSs), which usually occurs during the source water switch period, is a great concern of water utilities because of the potential occurrence of “red water” and customer complaints. This study developed a new method which combined in-situ water stagnation experiments with mathematical models and numerical simulations to predict the iron release caused by source water switch. In-situ water stagnation experiments were conducted to determine the total iron accumulation in nine cast iron pipes in-service in Beijing when switching the local water to treated Danjiangkou Reservior water. Results showed that the difference in the concentration increment of total iron in 24 hr (ΔCITI,24), i.e. short-term iron release, caused by source water switch was mainly dependent on the difference in the key quality parameters (pH, hardness, nitrate, Larson Ratio and dissolved oxygen (DO)) between the two source waters. The iron release rate (RFe) after switch, i.e. long-term iron release, was closely related to the pipe properties as well as the DO and total residual chlorine (TRC) concentrations. Mathematical models of ΔCITI,24 and RFe were developed to quantitatively reveal the relationship between iron release and the key quality parameters. The RFe model could successfully combine with EPANET-MSX, a numerical simulator of water quality for WDSs to extend the iron release modeling from pipe level to network level. The new method is applicable to predicting iron release during source water switch, thus facilitating water utilities to take preventive actions to avoid “red water”. 相似文献
208.
Yihe Lü Zhimin Ma Zhijiang Zhao Feixiang Sun Bojie Fu 《Environmental management》2014,53(6):1066-1076
Land use and ecosystem services need to be assessed simultaneously to better understand the relevant factors in sustainable land management. This paper analyzed land use changes in the middle reach of the arid Heihe River Basin in northwest China over the last two decades and their impacts on water resources and soil organic carbon (SOC) storage. The results indicated that from 1986 to 2007: (1) cropland and human settlements expanded by 45.0 and 17.6 %, respectively, at the expense of 70.1, 35.7, and 4.1 % shrinkage on woodland, grassland, and semi-shrubby desert; (2) irrigation water use was dominant and increased (with fluctuations) at an average rate of 8.2 %, while basic human water consumption increased monotonically over a longer period from 1981 to 2011 at a rate of 58 %; and (3) cropland expansion or continuous cultivation led to a significant reduction of SOC, while the land use transition from grassland to semi-shrubby desert and the progressive succession of natural ecosystems such as semi-shrubby desert and grassland, in contrast, can bring about significant carbon sequestration benefits. The increased water consumption and decreased SOC pool associated with some observed land use changes may induce and aggravate potential ecological risks for both local and downstream ecosystems, including water resource shortages, soil quality declines, and degeneration of natural vegetation. Therefore, it is necessary to balance socioeconomic wellbeing and ecosystem services in land use planning and management for the sustainability of socio-ecological systems across spatiotemporal scales, especially in resource-poor arid environments. 相似文献
209.
ZHANG Ya-lei FANG Zhen-wei XU De-qiang XIAO Yi-ping ZHAO Jian-fu QIANG Zhi-min 《环境科学学报(英文版)》2005,17(2):271-275
An aerobic bacterium strain, F-3-4, capable of effectively degrading 2,6-di-tert-butylphenol(2,6-DTBP), was isolated and screened out from an acrylic fiber wastewater and the biofilm in the wastewater treatment facilities. This strain was identified as Alcaligenes sp. through morphological, physiological and biochemical examinations. After cultivation, the strain was enhanced by 26.3% in its degradation capacity for 2,6-DTBP. Results indicated that the strain was able to utilize 2,6-DTBP, lysine, lactamine, citrate, n-utenedioic acid and malic acid as the sole carbon and energy source, alkalinize acetamide, asparagine, L-histidine, acetate, citrate and propionate,but failed to utilize glucose, D-fructose, D-seminose, D-xylose, sedne and phenylalanine as the sole carbon and energy source. The optimal growth conditions were determined to be: temperature 37℃, pH 7.0, inoculum size 0.1% and shaker rotary speed 250 r/min. Under the optimal conditions, the degradation kinetics of 2,6-DTBP with an initial concentration of 100 mg/L was studied. Results indicated that 62.4% of 2,6-DTBP was removed after 11 d. The degradation kinetics could be expressed by Eckenfelder equation with a half life of 9.38 d. In addition, the initial concentration of 2,6-DTBP played an important role on the degradation ability of the strain. The maximum initial concentration of 2,6-DTBP was determined to be 200 mg/L. Above this level, the strain was overloaded and exhibited significant inhibition. 相似文献
210.
海绵社区是海绵城市建设的重要载体,其综合实施效能评价将综合反映海绵城市的建设成效。本文以从事青岛市海绵城市建设的专家经验、项目运行效果为依据,借助网络分析法原理,建立了青岛市综合实施效能评价体系,并以青岛某海绵社区的实施情况为基础,运用模糊综合评价法进行了综合实施效能评价,获得了较为合理的评价结论。 相似文献