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951.
952.
Eija K. Saski Raimo Mikkola Jussi V. K. Kukkonen Mirja S. Salkinoja-Salonen 《Environmental science and pollution research international》1997,4(4):194-202
Environmental properties of organic matter contained halogen and sulfur were studied in sediments of bleached kraft pulp mill
effluent (BKME) recipient lakes and 2 m3 outdoor enclosures (mesocosms). The BKME contributed to 1% (v/v) of the total water flow in the lake downstream of the pulp
mill where the sediments contained 1.7 to 4 mg of tetrahydrofuran extractable organic halogen (EOX-Cl) and 0.6 to 0.8 mg of
tetrahydrofuran extractable organic sulfur (EOS-S) g−1 of organic matter. Upstream sediment contained 0.03 mg of EOXCl and 0.7 mg of EOS-S g−1 of organic matter. EOX was a better indicator for the influence of BKME in the recipient sediment than EOS. The polarity
of BKME contained EOX corresponded to log Kow of < 1, and that of the downstream sediment contained EOX to > 4.5. HP-SEC analysis of the molecular weight distribution
(MWD) of the EOX showed a peak between 300 to 600 g mol−1 for the BKME and between 1000 to 2000 g mol−1 for the downstream sediment. The MWD of the BKME contained EOS peaked at 300 to 1000 g mol−1, and that of the downstream sediment contained EOS at 1000 to 5000 g mol−1. These results indicate that BKME contained organic halogen and sulfur undergo major structural transformations when incorporated
into sediment. The biota-to-sediment accumulation factor (BSAF) of EOX from sediments formed downstream of the mill and in
the mesocosms to the lipids ofLumbriculus variegatus was 0.4 to 0.7. This is of a similar order of magnitude to the BSAF reported for 2,3,7,8-tetrachlorodibenzop-dioxin and 2,3,7,8-tetrachlorodibenzofuran. 相似文献
953.
954.
Faisal I. Khan Paul R. Amyotte 《Journal of Loss Prevention in the Process Industries》2005,18(4-6):310-326
This paper presents details of an integrated inherent safety index (I2SI). The conceptual framework of this index was presented at the 37th Annual Loss Prevention Symposium of the AIChE (2003) and published in Process Safety Progress (volume 23(2), 136–148, 2004). In addition to the framework, the current paper discusses additional features of the index such as the cost model and system design model, which were not presented or discussed earlier. I2SI is called an integrated index because the procedure considers the life cycle of the process with economic evaluation and hazard potential identification for each option. I2SI is comprised of sub-indices which account for hazard potential, inherent safety potential, and add-on control requirements. In addition to evaluating these respective characteristics, there are also indices that measure the economic potential of the option. To demonstrate the applicability and efficacy of I2SI, an application of the index to three acrylic acid production options is also discussed in the paper. 相似文献
955.
New emergy indices for sustainable development 总被引:4,自引:0,他引:4
The emergy indices for the evaluation of system‘ s sustainable development ability were studied. Results indicated that the emergy indices are simplified and merged, and a new emergy index for sustainable development(EISD) is deduced. Employing EISD, two cases areconducted. The first one is to compare three different dike-pond agro-ecological engineering modes, which are: melon-melon-cabbage-four domestic fishes (mode I ), melon-melon-cabbage-pig-four domestic fishes (mode H ) and melon-melon-cabbage-pig-four domestic fishes combined with Siniperca chuatsi B. ( mode Ⅲ ).The result is that the EISD of mode I is 0.53. Mode Ⅱ‘ s EISD is 5.26 times of mode I ,and mode Ⅲ‘s EISD is 6.83 times of mode I The second one is to evaluate the development of Zhongshan City, Pearl Delta, during 1996 to 2000.The result indicated that the EISD of Zhongshan had appreciably declined from 1996 to 1998, and quickly improved from 1998 to 2000, partly because of its environment protection and product construction. Both of the two cases studies showed that EISD can assessment the sustainable development ability more roundly, with the consideration of environmental impact and social-economic effect at the same time. 相似文献
956.
研究了串联凝胶色谱系统的峰加宽效应.在该系统中,单分散标样的GPC谱图为低流出体积一侧较宽的不对称形式,以峰流出体积为界,这样的谱图可视作两个半侧正态函效的拼接.峰加宽效应还随淋出体积增大而加强,简单的直线方程可近似地描述分辨因子h随淋出体积的变化规律.在此基础上建立了腐殖酸GPC谱图峰加宽效应的校正方法.并根据实测结果计算了两个水生腐殖酸样品的分子量分布. 相似文献
957.
958.
本文对价分子连接指数(~m~vX)的计算方法作了简要介绍,着重讨论了有机污染物三阶价分子连接指数(~3~vX)与其角质层同水分配系数(Kcw)的关系。结果表明:~3~vX与logKcw存在良好的线性关系、Kcw主要受其分子的结构特征如氯取代基、烃链和芳香环的影响。本文介绍的分子连接指数模型为一准确预测有机污染物的Kcw值的有效工具。 相似文献
959.
本文以线性自由能理论为基础提出了一种利用分子轨道能预测有机物生物毒性的方法,并利用这种方法建立了预测氯代芳烃化合物发光菌毒性的定量相关方程。 相似文献
960.
各种分子遗传技术为不同生物种类间进行直接比较和分子水平的遗传多样性的度量、研究提供了新的途径。本文讨论了此类分子水平研究所取得的一些新的进展,并指出了有关分子工具应用于生物多样性研究中存在的一些问题。 相似文献