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41.
ZHANG Jimin ) LIU Shuang ) SUN Xue ) YANG Guanpin ) ZHANG Xuecheng ) * GAO Zhenhui ) ) North China Sea Monitoring Center SOA Fushun Road Qingdao P..R.China) College of Marine Life Sciences Ocean University of China Qingdao P..R.China 《中国海洋大学学报(英文版)》2003,2(1)
1 Introduction Nannochloropsissp .areoneofpotentialsourcesofpolyunsaturatedfattyacids ,especiallytheeicosapen taentaenoicacid (EPA ,C2 0∶5 ) ,whichisimportantforbothanimalsandhumans . Thefattyacidcompositionofthisalgaisaffectedbyvariousenvironmentalfactors ,suchaslightintensity(Sukeniketal.,1989;Sukeniketal.,1990 ) ,imply ingthatafactorinfluencingthephotosyntheticprocessmayaffectcellularfattyacidsynthesisandtheirmetabolism .AselectionprogramofincreasingcellularEPAcontenthasbeencarriedo… 相似文献
42.
There are more than 600 Cenozoic volcanic cones and craters with abeut 50 000 km2of lava flows in northeast China, which formed many volcanic clusters and shown the features of the continental rift - type volcanoes. Most volcanic activities in this area, especially in the east part of Songliao graben, were usually controlled by rifts and faults with the main direction of NE / NNE in parallel and become younger from the central graben towards its both sides, especially to the east continental margin. It is revealed that the volcanism occurred in northeast China was as strong as that occurred in Japan during the Miocene and the Quaternary. The Quaternary basalt that is usually distributed along river valley is called "valley basalt"while Neogene basalt usually distributed in the top of mounts is called "high position basalt". These volcanoes and volcanic rocks are usually composed of alkaline basalts with ultramafic inclusions, except Changbaishan volcano that is built by trachyte and pantellerite. 相似文献
43.
为了给公路设计部门提供选线依据,运用瞬变电磁法在山西境内的某两条高速公路隧道工程设计线路段上进行探测,以查明下覆不良地质构造的发育情况.通过对瞬变电磁法的探测能力进行理论上的讨论,对不同地电断面情况下的异常体电磁响应的定性分析,得出用瞬变电磁法探测不良地质体的可行性结论.经过资料处理,查出不良地质构造赋存的位置,解释结果与钻探资料完全吻合. 相似文献
44.
45.
抗旱保水剂膨润土-聚丙烯酸盐吸水树脂研究 总被引:2,自引:0,他引:2
利用丙烯酸盐在蒙脱石层间进行原位聚合,研究开发一种适用于农林业的抗旱保水剂。实验结果表明:聚合产物的综合性能较为理想,吸水树脂的保水作用主要体现在能够吸收大量的水,并且在压力下不脱水。 相似文献
46.
为了明确折扣方式下应税金额的确定方法,分别从计税销售额、营业额和所得额等方面进行分析,其结果将使纳税人的财务会计处理和具体纳税操作更为规范和准确。 相似文献
47.
Gang Zhao Yonggheng Zhao Jtasheng Huang Lonlong Feng Keliang Huang Qiuhe Peng Tan Lu 《Astrophysics and Space Science》1988,141(1):169-176
In this paper, the neutrino mass has been determined from SN1987a observation in a manner that the simultaneity of neutrino emission is not regarded as the starting point, but is itself defined through the analysis by Monte-Carlo simulation. The result is that the neutrino mass lies in 3–4 eV, possiblym
v
3.6 eV. Neutrino luminosity variation and neutrino spectrum are also obtained. Comparison with theories gives further support to the mass determination, and also predicts the mass of progenitor star of SN1987a to be in the range of 12–25M
.The project supported by the National Natural Science Foundation of China. 相似文献
48.
A model of the galactic centre with magnetic monopole has been presented here. The positron can be produced continuously through magnetic monopoles to induce baryon decay (Rubakov catalytic reaction) and a lot of energy can be released as well. The calculation results show that even if the galactic center contains only a few magnetic monopoles (=N
M/NB10–24), this massive object can not collapse into a black hole. This model can explain the observed intensities of the annihilation line and higher energy photons ofE
>511 keV from the galactic centre.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
49.
Chemical structure of Jurassic vitrinites isolated from the coals in basins in NW China have been checked using solid state 13C NMR and flash pyrolysis-GC/MS. Study shows some Jurassic collodetrinites are rich in aliphatic products in pyrolysates, consisting with the high amount of methylene carbon in 13C NMR spectra. In contrast, pyrolysates of Jurassic collotelinites are rich in phenols and alkylbenzenes. Also one Pennsylvanian and one Permian vitrinite selected from the Ordos basin, NW China have been checked for comparison. The proportion of aliphatics is low in pyrolysates, and aliphatic carbon peak in 13C NMR spectrum of Permian vitrinite is mostly composed of gas-prone carbons compared with collodetrinites in those Jurassic basins. But both pyrolysis and 13C NMR data shows the Pennsylvanian vitrinite is not only gas-prone but also oil-prone. Relatively high proportion of long chain aliphatic structure of some Jurassic vitrinite in Junggar, Turpan-Hami basins may be due to the contribution of liptodetrinites, which may be included during the formation of vitrinites. And it seems that suberinite is the most possible precursor of long chain aliphatics in the structure of Jurassic collodetrinite. 相似文献
50.