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141.
Kaneda M Asaoka S Ikeda H Mori T Wada T Inoue Y 《Chemical communications (Cambridge, England)》2002,(12):1272-1273
A hydrostatic pressure of up to 750 MPa induced discontinuous changes in the enantiomeric excess of the (E)-isomer obtained in the enantio-differentiating photoisomerization of (Z)-cyclooctene and (Z,Z)-cycloocta-1,5-diene, sensitized by chiral benzene-1,2,4,5-tetracarboxylates; indicating a switching of the enantio-differentiation mechanism, which is attributable to dramatic conformational changes of chiral alkoxycarbonyl auxiliaries at a specific pressure. 相似文献
142.
[reaction: see text] A ruthenium catalyst precursor bearing a bulky and electron-donating pentamethylcyclopentadienyl (Cp) ligand, typically CpRuH3(PPh3), mediates hydrosilylation of several 1-alkynes with novel regioselectivity to give preferentially 2-silyl-1-alkenes. 相似文献
143.
The transgalactosylation rate catalyzed by the lipid-coated beta-d-galactosidase in supercritical fluoroform (scCHF3) can be reversibly controlled by changing temperature or pressure (reflecting polarity changes) without damaging enzymes. 相似文献
144.
A nonlinear optical crystal YCa(4)O(BO(3))(3) (YCOB) is phase matchable for third-harmonic generation (THG) of a Nd:YAG laser by type I mixing between 1.064 and 0.532mum . By partial substitution of Gd for Y in YCOB, a solid solution Gd(x)Y(1-x)Ca(4)O(BO(3))(3) gradually changes the phase-matching angles of THG to (theta, ?)=(90( degrees ), 90 ( degrees )) . We present the properties of noncritically phase-matched THG in Gd(x) Y(1-x)Ca(4)O(BO(3))(3) (x=0.28) . 相似文献
145.
Kenji Mori Shigefumi Kuwahara Mitsuhiko Fujiwhara 《Journal of Chemical Sciences》1988,100(2-3):113-117
A mixture of the four stereoisomers of 2.6-dimethyloctyl formate was synthesized, and found to be a potent mimic of (4R,8R)-4,8-dimethyldecanal, the aggregation pheromone of the flour beetles,Tribolium castaneum andTribolium confusum.
For Part CVI, see Mori K and Puapoomchareon P 1988Liebigs Ann. Chem. 175 相似文献
146.
Yasushi Mori Norio Ookubo Reinosuke Hayakawa Yasaku Wada 《Journal of Polymer Science.Polymer Physics》1982,20(11):2111-2124
The dc component Δn of the electric birefringence of poly(γ-benzyl-L -glutamate) in m-cresol is measured under an ac electric field at frequencies from 0.5 Hz to 200 kHz for solutions covering the dilute and semidilute regions. The dispersion curve indicates that at low frequencies Δn decreases with increasing frequency (low-frequency relaxation). For high-molecular-weight polymers at high concentration, Δn becomes negative at high frequency and its absolute value decreases with further increase in frequency (high-frequency relaxation). A unified theory for the two relaxations is developed on the basis of a model in which, in the semidilute regime, the rodlike polymer is confined in a cage formed by neighboring polymers and the lifetime of the cage lies between relaxation times of the two relaxations. The low-frequency relaxation is ascribed to end-over-end rotation of the polymer and the high-frequency relaxation to the rotation within a limited angle in the cage. The dependences of relaxation parameters on polymer concentration and molecular weight are reasonably explained by the theory. 相似文献
147.
S. Carboni A. Da Settimo D. Hertini C. Mori I. Tonetti 《Journal of heterocyclic chemistry》1971,8(4):637-642
The sulfuration of various anthyridones (I) to the corresponding thioderivatives (II) and the desulfuration of these to 5,10-dihydroanthyridine (III) is descrihed. The preparation of anthyridin-5-one (1d) from 6 -methyl-2,2 -dipyridylamino-3-carboxylic acid (V) is also described. 相似文献
148.
A model calculation of resonance Raman scattering tensors has been carried out for a diatomic molecule with a harmonic potential for the ground state and a linear repulsive potential for the excited state. Expressions for scattering tensors have been obtained by using a series of recurrence formulas induced from the Green function of the nuclear hamiltonian of the repulsive potential of the excited state and nuclear wavefunctions for the harmonic potential. The relative scattering intensities of overtones depend on the gradient of the repulsive potential curve and are interpreted in terms of the overlap integrals between nuclear wavefunctions of upper and lower states. 相似文献
149.
150.
The coupled vibrations of a cylindrical shell were analysed by a new method that we called ‘the apparent-elasticity method’. Several types of radiators using cylindrical shells were designed on the basis of analytical results and several acoustical characteristics were measured. In consequence, the analytical results were in good agreement with the experimental data, and the practicability of high intensity ultrasonic radiators using cylindrical shells was demonstrated. 相似文献