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11.
Isabella A. Abbott 《中国海洋湖沼学报》1995,(4)
A new species of Liagora,L.perennis sp.nov.from Hawai’i,is described.Unlike dpecies of this genus in China,it is carpotetrasporangial,and at the place of expected carposporangia bears cruciately di-vided tetrasporangia,a detail which differentiates it from the usual species of Liagora without tetraspores that have been reported in China.Notes are provided on other Liagora species that have an impact on the taxonomy of species found in China. 相似文献
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中国的蒸发岩矿床非常丰富,与蒸发岩在成因上密切相关的盐溶角砾岩极其发育。本文简述了中国盐溶角砾岩的分布,总结了盐溶角砾岩的一般特征,划分出盐溶角砾岩的主要类型,探讨了盐溶角砾岩与盐泉的关系。 相似文献
13.
Irvine WM Friberg P Hjalmarson A Ishikawa S Kaifu N Kawaguchi K Madden SC Matthews HE Ohishi M Saito S Suzuki H Thaddeus P Turner BE Yamamoto S Ziurys LM 《The Astrophysical journal》1988,334(2):L107-L111
We report the astronomical identification of the cyanomethyl radical, CH2CN, the heaviest nonlinear molecular radical to be identified in interstellar clouds. The complex fine and hyperfine structures of the lowest rotational transitions at about 20.12 and 40.24 GHz are resolved in TMC-1, where the abundance appears to be about 5 x 10(-9) relative to that of H2. This is significantly greater than the observed abundance of CH3CN (methyl cyanide) in TMC-1. In Sgr B2 the hyperfine structure is blended in the higher frequency transitions at 40, 80, and 100 GHz, although the spin-rotation doubling is clearly evident. Preliminary searches in other sources indicate that the distribution of CH2CN is similar to that for such carbon chain species as HC3N or C4H. 相似文献
14.
An observational test--the detection of a hydrogen coma around comets at large heliocentric distances--is proposed for determining whether comets were formed by the agglomeration of unaltered, ice-coated, interstellar grains. Laboratory experiments showed that amorphous water ice traps H2, D2, and Ne below 20 K and does not release them completely until the ice is heated to 150 K. Gas/ice ratios as high as 0.63 are obtainable. Thus, if the ice-coated interstellar grains were not heated above approximately 110 K, prior to their agglomeration into cometary nuclei, the inward propagating heat waves should release from the comets a continuous flux of molecular hydrogen. This flux would exceed that of water molecules at approximately 3 AU preperihelion and approximately 4 AU postperihelion. 相似文献
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We have used observations of the rare isotopes of HCN and HNC to determine the relative abundance of these two chemical isomers along the central ridge of the Orion molecular cloud. The abundance ratio [HCN]/[HNC] decreases by more than an order of magnitude from the relatively warm plateau and hot core sources toward the KL nebula to the colder, more quiescent clouds to the north and south. Even in the cooler regions, however, the ratio is an order of magnitude larger than that found in previous investigations of cold dark clouds. We determine the kinetic temperature in the regions we have studied from new observations of methylacetylene (CH3CCH), together with other recent estimates of the gas temperature near KL. The results suggest that the warmer portions of the cloud are dominated by different chemical pathways than those in the general interstellar cloud material. 相似文献
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Zoya A. Bessudnova 《《幕》》2008,31(3):368-369
In 2006, the Moscow publishing house Nauka (Science) published a 246-page book by Zoya A. Bessudnova entitled Geological Research at the Natural History. Museum of Moscow University, 1759-1930 as No. 32 in its series "Sketches on the History of Geological Knowledge'. The author is a geologist and Senior Researcher in the Department for the History of Geology of the Vernadsky State Geological Museum of the Russian Academy of Sciences, and a member of the International Commission on the History of Geological Sci- ences (INHIGEO). 相似文献
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制图学教育在俄罗斯高等综合大学已有65年的历史(1929~1994),早在1929年制图专业就已在莫斯科大学地理系创建。当今在俄罗斯培养高技能制图员的综合大学有莫斯科大学、圣彼得堡大学、伊尔库茨克大学、伊热夫斯克大学、萨兰斯克大学、特维尔大学以及最近(1994年)刚刚获得工程技术综合大学地位的老牌国家测量制图高等学校——莫斯科测绘学院。 相似文献
20.
AquantitativeanalysisontheEgyptianMediterraneanwaters¥M.A.SaidandF.M.Eid(ReceivedSeptember21,19931accfeptedJanuary15,1994)Abs... 相似文献