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61.
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钾原子中多种受激辐射参与的混频过程 总被引:2,自引:1,他引:1
当双原子共振激发钾原子于6S能级时,由光泵受激辐射和电离复合受激辐射参与的六波或四波混频,产生了位于紫外和紫区的诸多相干辐射、文中对多种混频机制进行了分析和讨论,并对所测得的相干辐射线进行了标识. 相似文献
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Isolation of lipase producer and its performance in enantioselective hydrolysis of glycidyl butyrate
A racemic glycidyl butyrate resolving strain, preliminarily identified as a Rhizopus sp., had been isolated from soil. Its extracellular lipase was found to enantioselectively hydrolyze the (S)-enantiomer of
the chiral ester, with optimal activities at pH 5.3 and 42°C. Higher en antioselectivity of theenzyme was observed at lower
temperatures, while the best anantioselectivity was obtained at pH 5.5–6.0, with an, E value (enantiomeric ratio) of 57. 相似文献
66.
The kinetics of ion exchange between Ca2 , Mg2 , Co(Ⅱ), Cu(Ⅱ),Ni(Ⅱ), Fe(Ⅲ), y3 or Sm3 , respectively, in 0.50 mol/L HC1 and H on macrorecticular sulfonic ion exchange resin and the kinetics of the same reactions (M -H exchange) when Mn(Ⅱ) coexisted in resin phase as accelerating ion were studied. The accelerating effect manifested and its rule are consistent with the accelerating effect theory based on the concept concerned with adsorption electrical double layer which has been suggested in a previous paper published. 相似文献
67.
A novel layered K(4)Ag(2)Sn(3)S(9) x 2KOH was synthesized solvothermally. A mixture of ethanol and HSCH(2)CH(SH)CH(2)OH was used for the synthesis. The HSCH(2)CH(SH)CH(2)OH plays an important role and appears to serve as a mineralizer for the solvothermal reaction. A layer comprises Sn(3)S(9)(6)(-) clusters linked by Ag(+) ions and possesses two types of 1D channels in which potassium ions are located. The compound crystallizes in the monoclinic P2(1)/m space group [a = 7.8071(2) A, b = 27.3508(1) A, c = 10.5008(2) A, alpha = 90 degrees, beta = 103.874(1) degrees, gamma = 90 degrees, Z = 4]. Its crystal structure, composition analysis, and IR are presented. 相似文献
68.
A novel mixed-ligand nickel complex, [Ni(PMBP—PNH) (Py)3], [PMBP—PNH=N-(1-phenyl-3-methyl-4-benzylidene-5-pyrazolone) p-nitrobezoylhydrazide; Py = pyridine], has been synthesized by the hydrothermal method and characterized by elemental analysis, IR spectrum, thermal analysis, and single-crystal X-ray diffraction. The X-ray diffraction reveals that the nickel (II) ion in the title complex is in a slightly distorted octahedral arrangement of the ONO donor atoms of primary ligand PMBP-PNH and three N-donor atoms in the secondary ligand pyridine. 相似文献
69.
Three new apianen lactones Maomailiaoine I ( 1 ), Maomailiaoine II ( 2 ) and Maoimaliaoine III ( 3 ), together with one known apianen lactone, five known flavonoids and three other known compounds were isolated from Polgonum ciliinerve Ohwi. Their structures were deduced from spectroscopic methods and 2D NMR techniques. 相似文献
70.