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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
921.
ZhengBin Zhang Chunying Liu Peifeng Li Zhenzhen Wu Cai Lin Huawei Huang Lei Xing Liansheng Liu 《Frontiers of Chemistry in China》2006,1(1):86-97
Many food algae and red tide algae were cultivated in the f/2 medium, and the nitric oxide (NO) concentration of the medium
and the cell density were determined. The experiments on algae were conducted when different concentrations of NO were added
into the medium using two methods. The results show that low concentrations of NO were self-produced by marine algae during
the exponential growth period and were about nmol/L level. But at the end of the period, i.e., 2 or 3 days before the cell
density reaches the maximum, an NO peak appeared, with the NO concentration reaching 10 nmol/L. The NO threshold concentration
exists according to the influence of exogenous NO on the marine phytoplankton growth. One type is the threshold concentration
that can promote algae growth, and its value is between 10 and 1 nmol level, or even lower. The other type can inhibit the
phytoplankton growth, which is about μmol level or higher. The results indicate that red tide algae are far more sensitive
to NO than are food algae. The fundamental experimental outcome above may provide a new clue for red tide chemical forecast
by inspecting the NO change. 相似文献
922.
Yu. I. Ryabukhin A. Yu. Eliseeva K. F. Suzdalev 《Chemistry of Heterocyclic Compounds》1992,28(2):236-237
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 280–281, February, 1992. 相似文献
923.
Ya. Yu. Nikitin 《Journal of Mathematical Sciences》1992,61(1):1891-1896
The local Chernoff efficiency of the sign and Wilcoxon statistics are derived for the testing of symmetry on the basis of the analysis of the probabilities of large deviations of these statistics under the hypothesis and the alternative.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 177, pp. 101–107, 1989. 相似文献
924.
Yu. N. Gordeev 《Fluid Dynamics》1995,30(6):870-876
The initial stage of propagation of a vertical hydraulic fracture in an impermeable or low-permeability stratum is considered within the framework of the pseudo-three-dimensional Perkins-Kern model.Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, pp. 79–86, November–December, 1995. 相似文献
925.
S. P. Timoshenko Institute of Mechanics, National Academy of Sciences of the Ukraine. Translated from Prikladnaya Mekhanika, Vol. 31, No. 9, pp. 15–23, September, 1995. 相似文献
926.
E.P. Yelsukov Yu.N. Vorobyov T.I. Arbusova I.B. Smolyak 《Journal of magnetism and magnetic materials》1994,130(1-3):44-50
We have measured the concentration dependence of the average magnetic moment per Fe atom
Fe(x) in microcrystalline and amorphous Fe-P alloys obtained over a wide concentration range using electrochemical deposition. The model of local magnetic moments has been used to described
Fe(x). On the basis of this model the effects of phosphorus on the value
Fe are explained in terms of the parameters of the local environment of the Fe atom. 相似文献
927.
L Jirovetz G Buchbauer W J?ger A Woidich A Nikiforov 《Biomedical chromatography : BMC》1992,6(3):133-134
After inhalation experiments with sandalwood oil and the pure fragrance compounds coumarin and alpha-terpineol, substances were detected and measured in the blood samples of test animals (mice) using gas chromatography/mass spectrometry (GC/MS) (MID) in connection with GC/FTIR (SWC), GC/AES (carbon and oxygen trace) and flame ionization detection/gas chromatography. Using tiglinic acid benzyl ester as the internal standard the following concentrations in serum could be found: alpha-santalol 6.1 ng/mL, beta-santalol 5.3 ng/mL and alpha-santalene 0.5 ng/mL. In separate inhalation experiments with coumarin and with alpha-terpineol the corresponding concentrations were 7.7 ng/mL and 6.9 ng/mL, respectively. 相似文献
928.
关于Echelon空间无穷矩阵变换集的有界性 总被引:1,自引:1,他引:0
无穷矩阵变换是研究序列空间理论的重要工具.研究一个空间到另一个空间无穷矩阵变换的形式,是序列空间理论中的重要内容,并且已有众多工作.本文将进一步研究一般的Echelon空间到空间lp(1≤p≤∞),c、c0的无穷矩阵变换集的有界性.所得结果的特例正是Echelon空间到lp(1≤p≤∞)c、c0无穷矩阵变换的形式,同时概括了前人的许多结果. 相似文献
929.
Yu. N. Obukhov 《General Relativity and Gravitation》1992,24(2):121-128
Cosmological models for a universe with expansion and rotation are considered. In particular, we analyse some effects of the universal rotation on the observational cosmology. It is shown that pure cosmic rotation does not produce neither causality voilations, nor parallax effects, nor anisotropy of the microwave background radiation. It can be detected by studying angular dependence of standard cosmological tests, and is directly measurable via polarization observations. The latter are used to obtain experimental estimates for the direction and value of the rotation of the universeThis essay received the third award from the Gravity Research Foundation, 1991 — Ed. 相似文献
930.