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排序方式: 共有1476条查询结果,搜索用时 171 毫秒
101.
102.
Arsenate zeolite analogues with 11 topological types 总被引:1,自引:0,他引:1
103.
104.
Hong Ping LI Hai Fei ZHANG Jun LIU Bu Xing HAN* Center for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2001,(4)
There are some unique advantages for chemical reactions in SCFs. For example, reaction rates, yields, and selectivity can be tuned by pressure or small amount of cosolvent. SCFs can be used to replace environmentally undesirable solvents. It is not surprised that in recent years the use of SCFs as solvents for chemical reaction media has received much attention. However, mechanism for the effect of pressure and cosolvents on chemical reactions is not very clear. Tautomeric reactions are id… 相似文献
105.
106.
Trent D Lund Timothy W West Lilyan Y Tian Lihong H Bu Daniel L Simmons Kenneth DR Setchell Herman Adlercreutz Edwin D Lephart 《BMC neuroscience》2001,2(1):20-13
Background
In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined. 相似文献107.
108.
A. Ya. Khaĭrullina M. V. Parhotz T. V. Oleĭnik L. M. Buĭ B. M. Dzhagarov 《Optics and Spectroscopy》2001,91(1):46-52
The potential of using multiple light scattering methods to monitor the state and concentration of photosensitizer and hemoglobin in whole blood is demonstrated. Samples of whole blood with various contents of chlorine e 6 photosensitizer were studied in the spectral region of 620–850 nm. On the basis of experimentally measured coefficients of diffuse reflection and transmission, absorption spectra of blood with and without the photosensitizer and the concentrations of oxy-, deoxy-, and methemoglobin in the samples are calculated. On the basis of this information, the absorption spectrum of chlorine e 6 in whole blood is reconstructed and its state and concentration are estimated for the first time. It is found that chlorine e 6 in whole blood occurs mainly in the monomer form. 相似文献
109.
110.
In this paper we study the Riemann and Hilbert problems of k-monogenic functions. By using Euler operator, we transform the boundary value problem of k-monogenic functions into the boundary value problems of monogenic functions. Then by the Almansi-type theorem of k-monogenic functions, we get the solutions of these problems. 相似文献