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571.
572.
In recent years, suspended particle pollution has become a serious problem in Taiwan. The carbonaceous materials EC and OC
are play important roles in various atmospheric processes. The primary OC/EC ratio approach is applied to assess the contribution
of secondary organic aerosol (SOA) to the PM2.5 and PM10 mass at the Taichung harbor sampling site. The results indicated that the average EC and OC concentration were 1.06 and 6.50 μg
m−3, respectively, in fine particulate. And the average EC and OC concentration were 4.04 and 40.32 μg m−3, respectively, in coarse particulate at Taichung Harbor sampling site. In addition, and the average EC/OC rations was 8.72
in fine particle, respectively, at Taichung Harbor, Taiwan during summer and autumn period of 2005. The fine particle exhibited
high particulate concentrations in October, and lower concentration particulate occurred in August. And in this study OC and
EC concentrations in this study are compared with those in other cities. The results of EC and OC concentration in this study
are also compare with those other cities. 相似文献
573.
Relatively few insects have invaded the marine environment, and only five species of sea skaters, Halobates Eschscholtz (Hemiptera: Gerridae), have successfully colonized the surface of the open ocean. All five species occur in the
Pacific Ocean, H. germanus White also occurs in the Indian Ocean, whereas H. micans Esch- scholtz is the only species found in the Atlantic Ocean. We sequenced a 780 bp long region of the mitochondrial cytochrome
oxidase subunit I gene (COI) for a total of 66 specimens of the five oceanic Halobates species. Our purpose was to investigate the genetic variation within species and estimate the amount of gene flow between
populations. We defined 27 haplotypes for H. micans and found that haplotype lineages from each of the major oceans occupied by this species are significantly different, having
sequences containing five to seven unique base substitutions. We conclude that gene flow between populations of H. micans inhabiting the Atlantic, Pacific, and Indian Ocean is limited and hypothesize that these populations have been separated
for 1 to 3 million years. Similarly, there may be limited gene flow between H. germanus populations found in the Pacific and Indian Ocean and between H. sericeus populations inhabiting the northern and southern parts of the Pacific Ocean. Finally, we discuss our findings in relation
to recent hypotheses about the influence of oceanic diffusion on the distribution and population structure of oceanic Halobates spp.
Received: 29 July 1999 / Accepted: 23 November 1999 相似文献
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577.
城市生活垃圾生命周期管理 总被引:20,自引:0,他引:20
生命周期评价是一种全面的环境管理工具,具有潜在的发展前景。0它通过对产品,产品系统,工艺活动整个生命周期的环境影响环境改善的机会进行评价。根据国际环境毒理与化学学会1993年和ISO14000环境管理体系中关于生命周期评价的技术框架,本文应生命周期评价在城市生产垃圾管理系统中的作用及管理系统的清单分析,影响评价和改善评价进行研究。 相似文献
578.
Implications of urine-to-feces ratio in the thermophilic anaerobic digestion of swine waste. 总被引:1,自引:0,他引:1
Thermophilic anaerobic digestion of swine manure represents a potential waste treatment technology to address environmental concerns, such as odor emissions and removal of pathogenic microorganisms. However, there are concerns relative to the stability of this process when swine manure is the sole substrate. In this study, the potential of biogas production from swine manure as the sole substrate under thermophilic (50 degrees C) conditions was investigated in the laboratory, to determine whether separation of urine and feces as part of the waste collection process would benefit anaerobic digestion. Effluent from a continuously stirred tank reactor was used as the inoculum for batch tests, in which the substrate contained three different concentrations of urine (urine-free, as-excreted urine-to-feces ratio and double the as-excreted urine-to-feces ratio). Inocula were acclimated to these same urine-to-feces ratios to determine methane production. Results show that both urine-free and as-excreted substrates were not inhibitory to anaerobic inocula. Anaerobic microorganisms can be readily acclimated to substrate with double the as-excreted urine concentration, which contained nitrogen concentrations up to 7.20 g/L. Cumulative methane production reached similar levels in the batch tests, regardless of the substrate urine concentration. 相似文献
579.
Pb/Zn冶炼废渣中重金属的生物浸出-盐浸处理 总被引:3,自引:0,他引:3
利用中温嗜热菌对某铅锌冶炼废渣进行生物浸出盐浸处理研究,并根据国家固体废物浸出毒性方法(HJ/T299-2007)对盐浸后余渣进行毒性分析。研究结果表明,在pH 1.5、温度65℃、矿浆浓度5%的优化条件下生物浸出3 d后,废渣中Cu、In、Ga和Zn的浸出率分别达到了91.5%、91.8%、84.9%和93.4%;盐浸生物浸出渣,其浸出液中Ag、Pb浓度分别为7.6和247.5 mg/L,可从废渣中有效回收Cu、In、Ga、Zn、Ag和Pb。生物浸出盐浸处理后余渣约为原渣量的70%;毒性分析浸出液中重金属元素Ag、As、Cd、Cu、Pb和Zn浓度分别为2~3.5、2~3、0.3~0.5、30~50、2~4、20~60 mg/L,低于国家危险废物鉴别标准(GB5085.3-2007)。根据试验结果,提出了针对冶炼废渣资源化、减量化、无害化的生物浸出盐浸联用工艺。 相似文献
580.
贵渝管道沿线地势险峻、构造活跃、雨量集中,崩滑流等地质灾害十分发育,科学开展管道沿线地质灾害的易发性评估工作对确保其安全运行至关重要。本研究在查明管道沿线自然地质环境及地质灾害分布的基础上,结合管道沿线地形地质特征、管道展布与斜坡体的相互空间位置关系划分了 101 段适合管道工程特点的评价单元,基于信息量数理统计模型与 Scoops3D 物理力学模型对管道沿线地质灾害的易发性进行了评价。评价结果表明管道沿线地质灾害的高易发区主要集中在遵义及桐梓县附近,其中 7 段处于极高易发区,26 段处于高易发区,20 段处于中易发区,30 段处于低易发区,18 段处于极低易发区。通过 ROC 曲线分别求得信息量、Scoops3D 以及二者联合模型的 AUC 值分别为 0.796、0.683 和 0.803,结果表明信息量-Scoops3D 联合模型的评价准确性最高。 相似文献