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611.
本文主要分析了太阳能供热单一系统的经济效益参数和偿还年限,并结合实例进行推导、计算,论证在平顶山市郊推广单一系统的可行性。 相似文献
612.
BiologicallyeffectiveradiationofsolarultravioletradiationandthedepletionofstratosphericozoneWangShaobin;SuWeihan(ResearchCent... 相似文献
613.
614.
大气臭氧总量的一个统计计算方法 总被引:3,自引:0,他引:3
根据大气臭氧和太阳紫外辐射的观测资料,利用相关分析,得到了计算臭氧总量的一个统计计算方法,并计算了1991年北京地区晴天和实际天然条件下臭氧总量的月平均值,计算结果表明,计算值与观测值吻合得比较好,计算值与观测值相对偏差的平均值小于2.5%,大气中的光化学反应是影响臭氧总量的主要因子。 相似文献
615.
Xiaoyi Wang Wei Shi Jiang Wu Yingqun Hao Guanjiu Hu Hongling Liu Xiaodong Han Hongxia Yu 《环境科学学报(英文版)》2010,22(2)
Water pollution of the Yangtze River in China became one of challenges that the government is facing today. Increasing numbers of petrochemical plants were built along the river in past decades, and numbers of organic chemicals were discharged into the river. Our goal was to establish in vitro system on rat sertoli cells, spermatogenic cells and leydig cells to investigate the reproductive toxicity potential induced by organic extracts from petrochemical effluents. Our results showed that the organic extract depressed the viability (p < 0.01) and destroyed the plasma membrane integrity of sertoli cells and spermatogenic cells to a certain degree. Accordingly, proportion of early apoptotic sertoli cells and late apoptotic spermatogenic cells increased significantly. Although significant morphological changes were not detected for leydig cells, the extract was observed to inhibit their testosterone production (p < 0.01). Sertoli cells and spermatogenic cells appeared to be more sensitive and maybe the main targets of the key toxins. These results suggested that the in vitro system on rat testicular cells may be useful to predicate reproductive toxicity potential of organic extracts from petrochemical effluents. More attention should be paid to the petrochemical effluents, because long-term accumulation of these organic compounds in organisms may cause spermatogenesis malfunction and testosterone reduction. 相似文献
616.
以我国典型淡水水华藻种铜绿微囊藻(Microcystis aeruginosa905)为研究对象,采用推流式低压紫外灯反应器研究在动态条件下Ultraviolet-C(UV-C)辐照对蓝藻生长抑制作用的效果.对数培养期的蓝藻液流经反应器进行UV-C辐照处理,其后正常培养,在培养期2 h、1 d、3 d、5 d、7 d、9 d分别取样,通过研究级倒置荧光显微镜在荧光视野下进行细胞计数.结果表明,辐照处理未引起铜绿微囊藻细胞的大量破裂死亡,36~115 mW.s.cm-2剂量范围的UV-C辐照能在9 d内有效抑制2.6×105~2.7×105cells.mL-1的铜绿微囊藻细胞密度增长,31~50 mW.s.cm-2剂量范围的UV-C辐照能在9d内有效抑制9.0×105~1.15×106cells.mL-1的铜绿微囊藻细胞密度增长. 相似文献
617.
Mieke W. J. C. Jansen Karin Korver-Hakkennes Dik van Leenen Willy Visser Peter A. in 't Veld Christianne J. M. de Groot Juriy W. Wladimiroff 《黑龙江环境通报》2001,21(12):1022-1026
Although the pathophysiology of pre-eclampsia is unknown, several studies have indicated that abnormal placentation early in pregnancy might play a key role. It has recently been suggested that this abnormal placentation may result in transfusion of fetal cells (feto-maternal transfusion) in women with pre-eclampsia. In the present study, fetal nucleated red blood cells were isolated from 20 women with pre-eclampsia and 20 controls using a very efficient magnetic activated cell sorting (MACS) protocol. The number of male cells was determined using two-color fluorescence in situ hybridization (FISH) for X and Y chromosomes. Significantly more XY cells could be detected in women with pre-eclampsia (0.61±1.2 XY cells/ml blood) compared to women with uncomplicated pregnancies (0.02±0.04 XY cells/ml blood) (Mann–Whitney U-test, p<0.001). These results suggest that fetal cell trafficking is enhanced in women with pre-eclampsia, and this finding may contribute to the understanding of the pathophysiology of the disease. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
618.
Fetal cells were enriched from maternal blood using density gradient centrifugation of Histopaque followed by magnetic-activated cell sorting (MACS) to select CD71-positive cells. For each specimen, cells partially purified by Histopaque were split into equal portions, and each portion was subjected to purification by MACS in parallel. Cells before and after MACS were subjected to dual-color fluorescence in situ hybridization (FISH) analysis with X- and Y-chromosome-specific probes. We found that the hybridization rates were decreased by approximately 10% after MACS based on duplicated analysis for each sample. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
619.
固定化皮氏伯克霍而德氏菌降解喹啉的研究 总被引:13,自引:0,他引:13
从焦化污泥中通过富集培养筛选到 1株以喹啉为唯一碳源和氮源的菌种 ,鉴定为 Bukholderia pickettii sp.,即皮氏伯克霍而德氏菌 ,革兰氏阴性菌 .采用固定化凝胶小球和纱布 - PVA复合载体固定化 ,对 2种方法降解喹啉的效果进行了比较 .就纱布 - PVA复合载体固定化微生物进行其降解喹啉的动力学研究 ,在喹啉浓度为 50 ,1 0 0 ,30 0 ,50 0 mg/L时 ,降解动力学方程遵循零级反应 ,降解速率常数随着喹啉初始浓度的升高而增加 . 相似文献
620.