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611.
A critical review of the development of the ecosystem concept is presented in this paper. An attempt to define the concept is discussed in details with reference to autonomy. 相似文献
612.
613.
采用网捕凝聚法对含Cu为1730~3820mg/l、COD为3984~5480mg/l的有机络合铜废水的处理工艺条件进行了研究。经实验室放大试验表明,在严格控制pH7.0~7.5条件下,加入凝聚剂生成絮体晶核来实现网捕凝聚,可使出水中铜为0.2~2.0mg/l,然后采用生物流化床对此废水进行生物降解,可使排放水中铜和COD达到或接近排放标准。 相似文献
614.
植树造林已普遍作为减缓全球变暖的主要对策之一,其主导思想是利用森林的光合作用吸收大气中的CO_2。目前很少人注意到缓解全球变暖的另一种途径,即从森林生物量中获取替代矿物燃料的生物能源。 相似文献
615.
该文分析了企业实施清洁生产的重要意义,阐述了政府组织、企业实施和政策配套是推进清洁生产的三个主要环节,并结合福建省建设生态省的环境保护工作要求,提出依法推进清洁生产工作的对策建议。 相似文献
616.
探讨了加入WTO对贸易与环境管理职能的影响,强调突破绿色壁垒,必须发挥政府宏观调控职能,规范和发展环境产业市场,发展生态产业和绿色贸易。 相似文献
617.
Kangwei Li Chao Lin Chunmei Geng Stephen White Linghong Chen Zhier Bao Xin Zhang Yanyun Zhao Lixia Han Wen Yang Merched Azzi 《环境科学学报(英文版)》2020,32(9):14-22
A new state-of-the-art indoor smog chamber facility (CAPS-ZJU) has been constructed and characterized at Zhejiang University, which is designed for chemical mechanism evaluation under well-controlled conditions. A series of characterization experiments were performed to validate the well-established experimental protocols, including temperature variation pattern, light spectrum and equivalent intensity (JNO2), injection and mixing performance, as well as gases and particle wall loss. In addition, based on some characterization experiments, the auxiliary wall mechanism has been setup and examined. Fifty chamber experiments were performed across a broad range of experimental scenarios, and we demonstrated the ability to utilize these chamber data for evaluating SAPRC chemical mechanism. It was found that the SAPRC-11 can well predict the O3 formation and NO oxidation for almost all propene runs, with 6 hr Δ(O3 – NO) model error of –3% ± 7%, while the final O3 was underestimated by ~20% for isoprene experiments. As for toluene and p-xylene experiments, it was confirmed that SAPRC-11 has significant improvement on aromatic chemistry than earlier version of SAPRC-07, although the aromatic decay rate was still underestimated to some extent. The model sensitivity test has been carried out, and the most sensitive parameters identified are the initial concentrations of reactants and the light intensity as well as HONO offgasing rate and O3 wall loss rate. All of which demonstrated that CAPS-ZJU smog chamber could derive high quality experimental data, and could provide insights on chamber studies and chemical mechanism development. 相似文献
618.
619.
Xiaoyang Yang Chunmei Geng Xuesong Sun Wen Yang Xinhua Wang Jianhua Chen 《环境科学学报(英文版)》2016,28(2):28-34
Polycyclic aromatic hydrocarbons(PAHs) are carcinogenic or mutagenic and are important toxic pollutants in the flue gas of boilers. Two industrial grade biomass boilers were selected to investigate the characteristics of particulate-bound PAHs: one biomass boiler retro-fitted from an oil boiler(BB1) and one specially designed(BB2) biomass boiler. One coal-fired boiler was also selected for comparison. By using a dilution tunnel system, particulate samples from boilers were collected and 10 PAH species were analyzed by gas chromatography–mass spectrometry(GC–MS). The total emission factors(EFs) of PAHs ranged from 0.0064 to0.0380 mg/kg, with an average of 0.0225 mg/kg, for the biomass boiler emission samples. The total PAH EFs for the tested coal-fired boiler were 1.8 times lower than the average value of the biomass boilers. The PAH diagnostic ratios for wood pellets and straw pellets were similar.The ratio of indeno(1,2,3-cd)pyrene/[indeno(1,2,3-cd)pyrene + benzo(g,h,i)perylene] for the two biomass boilers was lower than those of the reference data for other burning devices, which can probably be used as an indicator to distinguish the emission of biomass boilers from that of industrial coal-fired boilers and residential stoves. The toxic potential of the emission from wood pellet burning was higher than that from straw pellet burning, however both of them were much lower than residential stove exhausts. 相似文献
620.
在经典的DEA模型的基础上进行了修正,采用四阶段DEA模型,旨在剔除环境控制变量对效率测度结果的影响.同时,在DEA模型的基础上引入Malmquist指数分析法,以弥补DEA模型无法测度面板数据的缺陷.选取了2012年-2014年A股节能环保上市公司的面板数据,测度了样本的融资效率及三年的融资效率变化情况,结果表明:资源循环利用行业的融资效率最高,其次是环保行业,融资效率最低的是节能行业.样本企业总体的融资效率每年都在增长,但增长速度开始放缓. 相似文献