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111.
112.
The effects of the substitutions of 3d-, 4d- and 5d-transition metals for silicon on magnetostriction of Co-based amorphous alloys have been investigated by measuring the tension dependence of anisotropy field in magnetic hysteresis loop. Fractional changes of the magnetostriction with transition metal solutes in Co-based amorphous alloys are qualitatively discussed in terms of the magnetic moment and coordination number, and classified into 3 types, i.e., positive, negative and complicated types, from a viewpoint of the contribution to magnetostriction.  相似文献   
113.
This review of the properties of leptons, mesons, and baryons is an updating of Review of Particle Properties, Particle Data Group [Rev. Mod. Phys. 45, No. 2, Part II, Supplement (1973)]. Data are evaluated, listed, averaged, and summarized in tables.  相似文献   
114.
Methyl-p-benzoquinone (MQ) gives a single polarographic wave in methyl cellosolve media containing perchlorate as supporting electrolyte, but a prewave corresponding to the reaction Q + 2HA + 2e ái H2Q + 2A-, is found when an acid is added. The height of the prewave is proportional to the concentration of added acid. Traces (ca. 0.2%) of free perchloric acid can be determined in crude lithium perchlorate.The half-wave potential of the prewave depends on the pKa value of the acid; if the dissociation constants of acids differ sufficiently, two prewaves are found and each acid species can be determined simultaneously. This method was applied to the MQ-HClO4-CH3COOH, MQ-CCl3COOH-CH3COOH and MQ-CHCl2COOH- CH3COOH systems.  相似文献   
115.
A new antitumor antibiotic, adenopeptin (1), was isolated from the culture broth of Chrysosporium sp. PF1201. The planar structure, which includes a tridecapeptide and a hexahydropyrrolo[1,2-a]pyrimidinium, was elucidated by mass spectrometric and NMR experiments. Adenopeptin (1) induced apoptotic cell death in cells transformed with the adenovirus oncogenes.  相似文献   
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We point out that there might have been seen a structure in differential KS regeneration cross sections in nuclei near the diffraction-like minimum. A few neutrons in the peripheral region which behave incoherently with the majority of nucleons can account for the observed structure. The number of neutrons is estimated to be 1.16 for Pb.  相似文献   
118.
A full multiple theoretical model (MXAN) is applied to fit picosecond difference X-ray absorption spectra at the ruthenium L(3) edge upon photoexcitation of aqueous [RuII(bpy)3]2+. We show that fitting difference spectra allows an increase in sensitivity, such that slight structural changes can be retrieved, which are not detected in fitting full spectra. The Ru-N bond distances of the excited complex in the (3)MLCT state are in good agreement with recently published values. The implementation of the present approach to L-edge spectra and its high sensitivity opens opportunities for its extension to a large class of experiments where difference X-ray absorption spectra are recorded.  相似文献   
119.
To study the atomistic behavior of the phosphoric ester molecule on the nascent Fe surface under boundary lubrication conditions, we adopted a hybrid tight-binding quantum chemical molecular dynamics method. First, we investigated chemical interactions between phosphoric ester and the nascent Fe surface. Phosphoric ester was shown to interact with the nascent Fe surface, forming both covalent and ionic bonds. Formation and dissociation dynamics of covalent bonds during tribochemical reaction was clearly observed during the simulation. The effect of friction condition on the tribochemical reaction dynamics was then studied, and it was indicated that friction would influence the formation and the dissociation of covalent bonds. By using a hybrid tight-binding quantum chemical molecular dynamics method, we obtained insights on initial tribochemical reaction processes for the formation of tribofilm from the phosphoric ester molecule on the nascent Fe surface.  相似文献   
120.
Photochemical properties of trans-3,3',5,5'-tetramethoxystilbene (TMST) have been studied in various polar solvents. The Stokes shift of trans-TMST was found to be increased with increasing solvent polarity. The fluorescence lifetime of trans-TMST experienced a large solvent effect changing from 2.3 ns in cyclohexane to 16.6 ns in acetonitrile. These results indicate that the excited singlet state of trans-TMST has a charge-transfer (CT) character. On the basis of the obtained results, the interior polar environment of a water-soluble TMST dendrimer is discussed.  相似文献   
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