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101.
The separation ratios for the overlapped bands of CH3D, CD3H and CH2D2 molecules have been obtained by a method based on the differences in molecular and electronic symmetry point groups. The signs of all the ∂P/∂Qi elements are established. Also, the atomic polar tensors and effective charges are calculated using the intensities of all five CHxD4−x molecules.  相似文献   
102.
Denitrifying capacity and doubling time were measured among 44 strains of Rhizobium belonging to 4 species: B. japonicum, R. lupini, R. meliloti et R. leguminosarum. There was no correlation between doubling time and the rate of production of N2O in the presence of C2H2 in B. japonicum and R. lupini. In 38 other strains, only denitrifying capacity was measured. The percentage of strains showing denitrification capacity varied according to the species: 70 % in B. japonicum, 90 % in R. lupini, 37 % in R. meliloti and 14 % R. leguminosarum. The strains of the latter species showed a very low level of denitrifying activity in comparison with the strains of the 3 other species.  相似文献   
103.
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105.
《Tetrahedron letters》1987,28(43):5115-5118
The hydroxylation of organometallic reagents (RM) by 2-sulfonyloxaziridines 1 is shown to involve a hemiaminal intermediate 2, whose stability is apparently related to the nucleophilicity of the hydroxylated product (ROH).  相似文献   
106.
《Tetrahedron letters》1987,28(33):3763-3766
The equilibrium constants at 25°C are 7.6 x 10−3 and 2.0 x 10−5 for triphenylmethyl bromide and bromodiazirine respectively.  相似文献   
107.
《Tetrahedron letters》1987,28(45):5435-5436
The synthesis of the agylcone of the antibiotic Gilvocardin-M by a sequential Meerwein Diels-Alder route is reported. The D-ring of the agylcone is attached by a halogen atom directed Meerwein arylation reaction and the A-ring is attached by a halogen atom directed Diels-Alder reaction. In the key step the directing chlorine atom is removed by a new thiophenylation reduction sequence.  相似文献   
108.
The optical properties of two-dimensional (2D) perovskites recently receive numerous research focus thanks to the strong quantum and dielectric confinement effects. In addition to the strong excitonic effect at room temperature, 2D perovskites also have appealing features that their optical properties can be flexibly tuned by alternating organic or inorganic layers. Particularly, 2D chiral perovskites and 2D perovskites based heterostructures are emerging as new platforms to extend their functionalities. To optimize performance of 2D perovskites-based optoelectronic devices, it is critical to understand the fundamentals and explore the strategies to engineer their optical properties. This review begins with an introduction to the excitons and self-trapped excitons of 2D perovskites. Subsequently, inorganic/organic layer effects on optical properties and 2D perovskites based heterostructures are discussed. We also discussed the nonlinear optical properties of 2D perovskite. We are looking forward to that this review can stimulate more efforts to understand and optimize the optical properties of 2D perovskites.  相似文献   
109.
ZnO microstructures have been grown from zinc chloride (ZnCl2) and ammonia solution at 100 °C for 1 – 24 hours. X‐ray diffraction, scanning electron microscope and field‐emission scanning microscope were utilized to investigate the structural properties and morphology of the ZnO crystals. Structural investigations show that phase‐pure hexagonal structure ZnO has been successfully synthesized, and the hexagonal structure ZnO can be achieved in solutions with an appropriate range of concentrations. Under our experimental conditions, several different morphologies of ZnO structures were obtained, including flower‐like and bar flower‐like. The relationship between the morphology and experimental conditions are discussed.  相似文献   
110.
针对磁致伸缩材料在弱磁场传感器领域的应用需要,采用迈克耳逊干涉原理实验测量了零应力条件下Tb-Dy-Fe材料和Fe-Ga合金的磁场响应灵敏度,以及不同应力下Fe-Ga合金的磁场响应特性和温度响应特性.实验结果表明:在零应力,外加磁场16 mT条件下,Fe-Ga合金的磁场响应灵敏度远高于Tb-Dy-Fe材料,更合适作为弱磁场传感器敏感材料;同时,在1.2 MPa预应力和26 mT偏置磁场下,Fe-Ga合金材料具有较好的磁场响应灵敏度和较大的饱和磁致伸缩系数,因而处在最佳工作状态.所得到的材料的磁场和温度响应曲线可作为弱磁场传感器参量设计的参考依据.  相似文献   
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