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91.
Hiroshi Onoue Masayuki Narisada Shoichiro Uyeo Hiromu Matsumura Kyo Okada Toshisada Yano Wataru Nagata 《Tetrahedron letters》1979,20(40):3867-3870
Allylazetidinones , , prepared by coupling of allylcoppers with chloroazetidinones , , were converted into carbapenem esters , – using an Emmons-Horner reaction to introduce the 6-side chain and an intramolecular Wittig reaction to form the carbapenem ring system. 相似文献
92.
Kouhei Hatanaka Shigeo Tanimoto Toyonari Sugimoto Masaya Okano 《Tetrahedron letters》1981,22(34):3243-3244
It has been found that the reaction of enol silyl ethers with 2-ethoxy-1,3-dithiolane proceeds smoothly in the presence of zinc chloride catalyst to afford half-protected 1,3-dicarbony1 compounds in moderately good yields. 相似文献
93.
S Sugimoto 《Radioisotopes》1979,28(11):669-674
Nitrato nitrosylruthenium complexes [RuNO(NO3)x(H2O)5-x] (3-x)+ readily dissociate in aqueous solutions with decrease in pH and increase in electrical conductivity of the solutions. This study aimed to elucidate the behaviours of dissociation of the complexes with time. The change in the amount of undissociated complexes was determined with time. The results indicated that the dissociation was a multi-order reaction involving both protolysis and hydrolysis. The protolysis completed in relatively short period within(several tens of minutes), but it depended on the concentration of the complexes in the solution. The completion of the protolysis and the formation of the resulting dissociation products were observed by absorption spectrometry. The dissociation products, which were assumed as aquohydroxy complexes, underwent the successive step-wise dissociation for a prolonged period as revealed by pH measurements. The rate constants involved in the step-wise dissociation, process were obtained. The degree of dissociation and dissociation constant of the complexes were measured by conductometry. 相似文献
94.
95.
Toshinobu?YogoEmail author Reimon?Fukuzawa Wataru?Sakamoto Shin-ichi?Hirano 《Journal of nanoparticle research》2005,7(6):633-640
Nanocrystalline BaTiO3 particles modified with polarizable ligands were synthesized through hydrolysis of modified metal–organics below 100°C. BaTiO3 precursor was synthesized from barium metal, titanium isopropoxide and polarizable ligands in a mixture of ethanol and 2-ethoxyethanol.
The modified Ba–Ti complex alkoxide was hydrolyzed yielding BaTiO3 particles modified with organics. The crystallinty of nanometer-sized particles was dependent upon the hydrolysis conditions,
and increased with increasing water amount and time. The nanocrystalline particles were identified to be BaTiO3 by X-ray diffraction (XRD) and electron diffraction. A fluid consisting of modified BaTiO3 particles and silicone oil revealed a typical electrorheological (ER) behavior on applying DC field. The ER behavior was
found to depend upon the kind of ligand. 4-Fluorobenzyloxy modifier revealed the highest yield stress in the ER measurement
among 4-substitued benzyloxy ligands examined. 相似文献
96.
We calculate scattering functions S(q-->,omega) of neutron Compton scattering (NCS) for a proton (deuteron) pair in the entangled state caused by the indistinguishability of particles. From the calculation, it is concluded that the effect of entanglement on the scattering intensity is undetectable in NCS experiments because of their high energy transfer and broad energy resolution. 相似文献
97.
Tanaka Y Hoshino W Shimizu S Youfu K Aratani N Maruyama N Fujita S Osuka A 《Journal of the American Chemical Society》2004,126(10):3046-3047
When heated, bis-Cu(II) octaphyrin(1.1.1.1.1.1.1.1) is quantitatively split into two Cu(II) porphyrins both in solution and film states, which is accompanied by large absorption spectral changes. 相似文献
98.
Akira Sugimoto 《Tetrahedron》2004,60(48):10883-10886
Irradiation of 9-methylene-9,10-dihydrophenanthrene (1) in the presence of 1,1-diphenylethene or styrene in benzene afforded ene-reaction adduct in good yield. In the absence of arylalkenes, the dimerized product of 1, 9-[2-(9-phenanthryl)ethyl]-9,10-dihydrophenanthrene, and 9-methylphenanthrene were obtained as major products. 相似文献
99.
We observed a small-signal gain of Ar2* emission at 126 nm by use of a hollow fiber to guide the high-intensity laser propagation in high-pressure Ar. The small-signal gain coefficient was measured to be 0.05 cm(-1) at 126 nm. Kinetic analysis revealed that the electrons produced by the high-intensity laser through an optical-field-induced ionization process initiated the Ar2* production processes. The increase in the emission intensity was measured to be exp(2.5), with an increase in the fiber length. 相似文献
100.