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81.
Recent achievements in three nucleon force study via three nucleon scattering at intermediate energies ${(E/A \approx 100-200 {\rm MeV})}$ are discussed.  相似文献   
82.
Recent achievements in three nucleon force study via three nucleon scattering at intermediate energies ( ${E \gtrsim 100 \,\,{\rm MeV/nucleon}}$ ) are discussed.  相似文献   
83.
The reaction of an imidazolium salt with LiBEt(3)H afforded triethylborane adduct of imidazol-2-ylidene, which can act as a carbene precursor for the synthesis of a transition metal complex as well as a main group element complex.  相似文献   
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85.
M(2)L(4) molecular capsules self-assembled from M(II) ions (where M = Zn, Ni, and Pd) and bent bidentate ligands constructed from anthracene fluorophores. The Ni(II) and Zn(II) capsules exhibited weak to strong blue emission unlike traditional Pd(II) cages and capsules.  相似文献   
86.
A new method for measuring delayed luminescence (delayed fluorescence) employs preillumination and a dark waiting period before normal excitation. The preillumination results in a concavity and a convexity in the decay curve in delayed luminescence in the green alga Pseudokirchneriella subcapitata. Formation of the concavity and the convexity is not affected by excitation wavelength (680 nm and 700 nm). However, the concavity and the convexity progressively decrease as the dark waiting period increases after preillumination. The formation of the concavity and the convexity was inhibited by exposure to the electron transport inhibitors DBMIB (644 μg/L, 2.0 μM) and Antimycin A (55 μg/L, 0.1 μM). Samples exposed to DBMIB exhibited noticeable reduction in the concavity, whereas samples exposed to Antimycin A exhibited pronounced reduction in the convexity. There is a possibility that the formation and disappearance of the concavity and the convexity are due to the reduction–oxidation state of the plastoquinone pool and the cyclic electron transport. We expect this method being useful in evaluating the effects of chemicals (particularly toxic chemicals) on photosynthetic reactions, and the method may also help to resolve questions regarding the source of long delayed luminescence.  相似文献   
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88.
The reaction of delta-halo-gamma-oxide ylide, prepared from methylenetriphenylphosphorane and epichlorohydrin, with aldehydes afforded alkylidenecyclobutanols in moderate yields. The reaction initially proceeded through internal nucleophilic attack on delta-carbon of this ylide. Another novel approach toward the synthesis of 4-methylenetetrahydrofurans was achieved by the reaction of gamma-oxide ylides with paraformaldehyde.  相似文献   
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A new iridoid glucoside, named ladroside, together with mussaenoside (1) [2], has been isolated from Veronica officinalis L . The structure of ladroside (4) and the identity of mussaenoside have been established by spectral analysis. Additionally, the absolute configuration at C(8) carrying the tertiary hydroxyl group has been established by chemical evidence.  相似文献   
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