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691.
上海城市交通与机动车排气污染调查 总被引:12,自引:0,他引:12
上海市机动车保有量逐年增加,车辆的排气污染愈来愈严重,据调查,1997年机动画排放的CO,MNHC,NOX和PM分别达到58.6,9.08,6.20和0.23万吨。中心城区机动车排放的CO,NMHC和NOX污染物50%以上来自于小型车,是影响上海城区环境空气质量的主要污染源。 相似文献
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环境信息国际交流制度,已成为国际环境法的一项基本法律制度,其内容涉及各国和国际组织在这项交流中的地位,作用及机构,权利和义务,交流范围和形式,这项制度对有效保护人类环境发挥了多方面积极作用,在尊重各国主权,合作取得和共同享有,支持发展中国家参与交流原则基础上,这项制度将日益丰富,多样,完善。 相似文献
694.
A. Kr?ner A. P. Willner E. Hegner A. Frischbutter J. Hofmann R. Bergner 《Geologische Rundschau》1995,84(3):437-456
Single zircons from two orthogneiss complexes, the Grey Gneiss and Red Gneiss, the lowermost tectonic units in the Erzgebirge, were dated. The grey Freiberg Gneiss is of igneous origin and has a 207Pb/206Pb emplacement age of 550±7 Ma. A quartz monzonite from Lauenstein contains idiomorphic zircons with a mean 207Pb/206Pb age of 555±7 Ma as well as xenocrysts ranging in age between 850 and 1910 Ma. Red gneisses from the central Erzgebirge contain complex zircon populations, including numerous xenocrysts up to 2464 Ma in age. The youngest, idiomorphic, zircons in all samples yielded uniform 207Pb/206Pb ages between 550±9 and 554±10 Ma. Nd isotopic data support the interpretation of crustal anatexis for the origin of both units. Nd(t) values for the grey gneisses are –7.5 and –6.0 respectively, (mean crustal residence ages of 1.7–1.8 Ga). The red gneisses have a wider range in Nd(t) values from –7.7 to –2.8 (T
DM ages of 1.4–1.8 Ga). The zircon ages document a distinct late Proterozoic phase of granitoid magmatism, similar in age to granitoids in the Lusatian block farther north-east. However, Palaeozoic deformation as well as medium pressure metamorphism ( 8 kbar/600–650° C) are identical in both gneiss units and distinguish these rocks from the Lusatian granitoids. The grey and red gneisses were overthrust by units with abundant high-pressure relicts and a contrasting P-T evolution. Zircon xenocryst and Nd model ages in the range 1000–1700 Ma are similar to those in granitoid rocks of Lusatia and the West-Sudetes, and document a pre-Cadomian basement in parts of east-central Europe that, chronologically, has similarities with the Sveconorwegian domain in the Baltic Shield. 相似文献
695.
Finn Stener Jørgensen MD 《黑龙江环境通报》1995,15(5):419-429
The aim of the study was to describe the opinion of pregnant women who had accepted or declined an alpha-fetoprotein (AFP) test, not only on AFP screening in general, but also on whether every pregnant woman should be offered amniocentesis (AC)/chorionic villus sampling (CVS) and an ultrasound scan for fetal malformations. An additional aim was to describe pregnant women's attitudes concerning continued research in the prenatal field. The study was performed as a questionnaire study in two regions over a 1-year period from 1 October 1988 to 30 September 1989. Results are based on answers from 3331 women who had taken an AFP test and 336 women who had declined the offer of a test. A total of 79 per cent of the women thought that an AFP test, 70 per cent that an ultrasound scan for fetal malformations, and 26 per cent that AC or CVS should be offered to all pregnant women. Fifty-nine per cent of the women were positive towards continued research in the prenatal field. Women who had had an AFP test were generally much more positive towards screening and research than women who had declined, who were generally against. Women who had left school without a high school degree were on average more positive towards the screening issues than women who had this degree. In conclusion, the results obtained in this study strongly suggest that women's attitudes are very dependent on how the prenatal screening programme is already organized in their local area. 相似文献
696.
Yun-Ling Zheng Maryann Demaria Dongkai Zhen Theresa J. Vadnais Diana W. Bianchi MD 《黑龙江环境通报》1995,15(10):897-905
Monoclonal antibody to fetal haemoglobin (a2γy2) has been proposed as a fetal-specific reagent. We developed an intracellular staining protocol that combines fluorescein isothiocyanate or phycoerythrin conjugated anti-γ with the DNA binding dye Hoechst 33342 to identify and flow sort fetal erythroblasts from maternal blood. Our preliminary observations on anti-γ-positive cells sorted from four different pregnant women are described here, using fluorescence in situ hybridization (FISH) with chromosome-specific probes to identify fetal cells. Our data demonstrate that far fewer candidate fetal cells are sorted with this protocol than by current cell surface staining methods that employ the monoclonal antibody CD71. This results in increased fetal cell sorting purities. With this protocol, standard FISH techniques require modification due to the rigorous fixation with 4 per cent paraformaldehyde. Our initial data indicate the promise of this approach. 相似文献
697.
主要介绍了工业牌号高强铝合金在供应态或经简单预处理后在通用油压机上超塑成形的实例,并分析探讨了非理想组织材料超塑成形中微观组织的变化。 相似文献
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