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41.
[reaction: see text] Radical cascade reaction with various 1,4-dienes and 1,4-enynes using dimethyl 2-(iodomethyl)cyclopropane-1,1-dicarboxylate as a homoallyl radical precursor smoothly proceeds through an iodine atom transfer mechanism to give functionalized bicyclo[3.3.0]octane derivatives in good yields. 相似文献
42.
The space of local operators in the SU(2) invariant Thirring model (SU(2) ITM) is studied by the form factor bootstrap method. By constructing sets of form factors explicitly we define a susbspace of operators which has the same character as the level one integrable highest weight representation of . This makes a correspondence between this subspace and the chiral space of local operators in the underlying conformal field theory, the su(2) Wess-Zumino-Witten model at level one. 相似文献
43.
[reaction: see text] The reaction of (o-silylphenyl)acetylene derivatives with lithium naphthalenide undergoes intramolecular reductive cyclization to produce various silaindene derivatives. On the basis of this methodology, a series of silaindene-containing pi-electron systems are synthesized that show intense blue to greenish-blue fluorescence. 相似文献
44.
Komoto A Maenosono S Yamaguchi Y 《Langmuir : the ACS journal of surfaces and colloids》2004,20(20):8916-8923
Fluorescence oscillation is observed in an ensemble of colloidal CdSe/ZnS core/shell quantum dots (QDs) dispersed in nonpolar solvent under continuous irradiation. The QDs dispersed in toluene gradually aggregate and change their fluorescence intensity, even in the dark. During the aggregation, the QD/toluene suspension is unstable, that is, overdispersed. The fluorescence oscillation is found only in this unstable state before the system reaches steady state. In addition, the aggregation rate is promoted by irradiation and strongly correlates with the oscillation amplitude. Our experimental results indicate that the dispersion instability plays an important role in both linear and nonlinear dynamics of the fluorescence. It is inferred from the experimental results and previous studies that the complex time evolution of fluorescence in the QD/toluene dispersion is possibly due to adsorption and desorption of surface ligand molecules over the course of QD aggregation. 相似文献
45.
Yamamoto K Sunagawa Y Takahashi H Muramatsu A 《Chemical communications (Cambridge, England)》2005,(3):348-350
Single nanometer-sized metallic Ni particles have been successfully deposited inside a hexagonally ordered mesoporous silica material by using a liquid-phase reductive deposition method. 相似文献
46.
Noguchi H Kondoh A Hattori Y Kanoh H Kajiro H Kaneko K 《The journal of physical chemistry. B》2005,109(29):13851-13853
We measured adsorption and desorption isotherms of methane on [Cu(4, 4'-bipyridine)2(BF4)2] (LPC) at 258, 273, and 303 K. Adsorption proceeds almost vertically at a definite pressure, which is named gate pressure. The lower the measurement temperature, the smaller the gate pressure. The temperature dependence of the gate pressure is expressed by the Clapeyron-Clausius equation, giving a thermodynamic evidence on the clathrate formation between the Cu complex and methane. 相似文献
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A novel dichiral compound possessing both an asymmetric axis and a chiral centre induces opposite twist senses and distinct helical pitches in different host nematic liquid crystals; the host-guest effect on chirality transfer is discussed in terms of molecular recognition. 相似文献