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K Mimura  S Baba 《Radioisotopes》1979,28(12):739-744
In order to perform the metabolic study of paeonol (I) in human and animals by using isotope tracer techniques, synthesis of I and its urinary metabolites labeled with carbon-13 or deuterium was investigated. 2-Hydroxy-4-methoxy[d3]acetophenone, 2,5-dihydroxy-4-methoxy[d3]acetophenone, and resacetophenone[acetyl-13C2] were synthesized from methyl iodide-d3, dimethyl sulfate-d6, and acetic acid-1,2-13C2, respectively. Physicochemical studies by IR and NMR spectra showed that stable isotope was not eliminated during the synthetic process of each compound. For the quantification of the metabolites by GC-MS analysis, isotope effect on gas chromatography and fragmentation was studied.  相似文献   
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Electroosmosis and streaming potential measurements were carried out across charged membranes made of collodion and sulfonated polystyrene. Experiments were confined to the range where linear flux/force relationships hold. Saxén's relationship holds between electroosmosis and streaming potential; for porous charged membranes these exhibit an approximate inverse proportionality to ionic mobility at the limit of low electrolyte concentration. Both tend towards zero at the limit of high electrolyte concentration.  相似文献   
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We investigate a possibility if a loop diagram via Higgsino can enhance the Higgs to diphoton decay width in supersymmetric models with an extension of Higgs sector. A model with an additional non-renormalizable term of Higgs fields is firstly analyzed where the higher order term can introduce the Higgs coupling to Higgsinos as well as charged Higgs bosons. We point out that a choice of the Higgs coupling to obtain a significant size of enhancement of diphoton decay width reduces the Higgs mass and/or a size of non-renormalizable term needs to be large and a cutoff scale is around the weak scale. Another model in which the Higgsino mass term is generated by a non-perturbative instanton effect via a strong dynamics in a context of SUSY QCD is also suggested. It is shown that the sign of the Higgs coupling to fermions is opposite from perturbative models due to an operator including bosonic fields in the denominator and a constructive contribution to the diphoton decay amplitude can be easily obtained in this kind of model.  相似文献   
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We calculated binding energies and wave functions of the 4He tetramer ground and excited states employing various realistic 4He?4He potentials which includes the currently most accurate one with the adiabatic, relativistic, QED and residual retardation corrections. We used our Gaussian expansion method (GEM) for ab initio variational calculations of few-body systems. We found that precisely the same shape of the short-range correlation (r ij < 4Å) in the dimer appear in the ground and excited states of trimer and tetramer. The four kinds of the binding energies of the trimer and tetramer ground and excited states, ${B_3^{(0)}, B_3^{(1)}, B_4^{(0)}}$ and ${B_4^{(1)}}$ , for the different potentials exhibit perfect linear correlations over the range of binding energies relevant for 4He atoms; namely, six types of the generalized atomic Tjon lines were observed.  相似文献   
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