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101.
T. Tsuchiya T. Sei Y. Watanabe M. Mori T. Kineri 《Journal of Sol-Gel Science and Technology》1997,8(1-3):685-688
Gold-dispersed BaTiO3, PGO and PLT thin films, which will be used for third-order nonlinear optical devices, were prepared by sol-gel process with
spin-coating using HAuCl44H2O, Ba(CH3COO)2, Ti[O(CH2)3CH3]4, Pb(CH3COO)23H2O, Ge[O-n-C4H9]4, La(CH3COO)31.5 H2O as starting materials. The thin films were heat-treated in air at temperatures ranging from 400 to 800 for 1 h. The nonlinear
optical property of these thin films was measured by the degenerate four-wave mixing (DFWM) method using a frequency-doubled
Nd: YAG laser with 20 ps pulse duration. Third-order nonlinear susceptibility χ(3) of gold-dispersed BaTiO3, PGO and PLT thin films with 5 vol% of gold were 1.410−6 esu, 3.510−7 esu respectively. The large χ(3) may be ascribed to the high dielectric constant of the films. 相似文献
102.
Takayuki Otsu Bunichiro Yamada Shigeru Sugiyama Shigeki Mori 《Journal of polymer science. Part A, Polymer chemistry》1980,18(7):2197-2207
Radical polymerization and copolymerization of some o-alkylphenyl methacrylates were carried out and the effect of the ortho-substituents on the ability to homopolymerize, on the monomer reactivities, and on the ceiling temperatures of the monomers was studied. The effect of the substituent on tacticities and thermal stabilities of the polymers formed was also discussed. The ability to honiopolymerize and the monomer reactivity were considerably decreased by the introduction of the o-substituent. 2,6-Di-tert-butylphenyl methacrylate formed no methanol-insoluble polymer at 60°C. On the basis of the tacticity determined it was noted that the o-substituted phenyl methacrylates preferred syndiotactic addition in the propagation reaction less than did phenyl methacrylate or methyl methacrylate. The polymers formed from the o-substituted monomers were thermally less stable than poly(phenyl methacrylate), and, consistent with this finding, ceiling temperatures of the o-substituted phenyl methacrylates seemed to be lower than that of phenyl methacrylate. The effects observed were characteristic of the o-substituents conformationally close to the carbon-carbon double bond of the monomer or the carbon carrying the unpaired electron of the polymer radical. 相似文献
103.
A new family of quaternary carbon and nitrogen containing Rare Earth (RE: Sc, Y, Ho, Er, Tm and Lu) borides: REB15.5CN, has been synthesized and structurally characterized by powder X-ray diffraction data. They are all isotypic with Sc1−xB15.5CN whose structure was solved based on single-crystal X-ray data and HRTEM investigations. The structure refinement converged at a R(F2) value of 0.044 for 364 reflections. The new structure type of Sc1−xB15.5CN is composed of a three-dimensional network based on interconnected slabs of boron (B12)ico icosahedra and (B6)oct octahedra. A linear [CBC] chain and nitrogen tightly bridges icosahedra. Sc partially occupies voids in the sheets of boron octahedra. It crystallizes with the trigonal space group P3m1, with Z=2. Lattice parameters (nm) are as follows: for RE: Sc, a,b=0.5568(4), c=1.0756(2); Y, a,b=0.55919(6), c=1.0873(2); Ho, a,b=0.55883(7), c=1.0878(6); Er, a,b=0.55889(5), c=1.0880(6); Tm, a,b=0.5580(1), c=1.0850(6); Lu, a,b=0.55771(9), c=1.0839(4). Magnetic characterization of ErB17C1.3N0.6 has been performed. 相似文献
104.
When a THF solution of beta-lactam having propargyl phosphate was warmed in the presence of 5 mol % of Pd(2)(dba)(3) x CHCl(3), 20 mol % of a bidentate ligand, and sodium acetate (1.5 equiv) at 40 degrees C for 22 h, carbapenam was produced in high yield. In this reaction, the lactam nitrogen attacked the central carbon of a eta(3)-propargylpalladium complex, which was formed from propargyl phosphate and Pd(0). 相似文献
105.
Yo Ueda K
ichi Mori Keiki Kouno Tokihiro Nhya 《Journal of mass spectrometry : JMS》1976,11(10):1027-1036
The mass spectra of 30 sulfinamide derivatives (RSONHR', R' alkyl or p-XC6H4) are reported. Most of the spectra had peaks attributable to thermal decomposition products. For some compounds these were identified by pyrolysis under similar conditions to be: RSO2NHR', RSO2SR, RSSR and NH2R' (in all kinds of sulfinyl amides); RSNHR' (in the case of arylsulfinyl arylamides); RSO2C6H4NH2, RSOC6H4NH2 and RSC6H4NH2 (in the case of arylsulfinyl arylamides of the type of X = H) The mass spectra of the three thermally stable compounds showed that there are several kinds of common fragment ions. The mass spectra of the thermally labile compounds had two groups of ions; (i) characteristic fragment ions of the intact molecules and (ii) the molecular ions of the thermal decomposition products. It was concluded that the sulfinamides give the following ions after electron impact: [M]+, [M ? R]+, [M ? R + H]+, [M ? SO]+, [RS]+, [NHR']+, [NHR' + H]+, [RSO]+, [RSO + H]+, [R]+, [R + H]+, [R']+ and [M ? OH]+, and that the thermal decomposition products give the following ions: [RSO2SR]+, [RSSR]+, [M ? O]+, [M + O]+ and [RSOC6H4NH2]+. 相似文献
106.
[reaction: see text]. The sum of the rate constants for solvolysis and 18O-scrambling of 4-MeC6H4(13)CH(Me)18OC(O)C6F5 in 50/50 (v/v) trifluoroethanol/water, k(solv) + k(iso) = 1.22 x 10(-5) s(-1), is larger than k(solv) = 1.06 x 10(-5) s(-1) for solvolysis of the unlabeled ester. This shows that the ion pair intermediate undergoes significant internal return. The data give k(-1) = 7 x 10(9) s(-1) for internal return by unimolecular collapse of the ion pair, which is significantly larger than k(Nu) = 5 x 10(8) M(-1) x s(-1) for bimolecular nucleophilic addition of carboxylate anions to 4-MeC6H4CH(Me)+. 相似文献
107.
(±)-Ascochlorin, 5-chloro-2, 4-dihydroxy-6-methyl-3-[(2, 4)-5-(1,2,6-trimethyl-3-oxocyclohexyl)3-methyl-3,4-pentadienyl] benzaldehyde, was synthesized in 14 steps from (±)-3,4-dimethyl-2-cyclohexenone. 相似文献
108.
R. S. Judson Y. T. Tan E. Mori C. Melius E. P. Jaeger A. M. Treasurywala A. Mathiowetz 《Journal of computational chemistry》1995,16(11):1405-1419
A genetic algorithm (GA) conformation search method is used to dock a series of flexible molecules into one of three proteins. The proteins examined are thermolysin (tmn), carboxypeptidase A (cpa), and dihydrofolate reductase (dfr). In the latter two proteins, the crystal ligand was redocked. For thermolysin, we docked eight ligands into a protein conformation derived from a single crystal structure. The bound conformations of the other ligands in tmn are known. In the cpa and dfr cases, and in seven of the eight tmn ligands, the GA docking method found conformations within 1.6 Å root mean square (rms) of the relaxed crystal conformation. © 1995 John Wiley & Sons, Inc. 相似文献
109.
Successive band-splitting transitions occur in the one-dimensional map xi+1=g(xi),i=0, 1, 2,... withg(x)=x, (0 x 1/2) –x +, (1/2 <x 1) as the parameter is changed from 2 to 1. The transition point fromN (=2n) bands to 2Nbands is given by=(2)1/N (n=0, 1,2,...). The time-correlation function
i=xix0/(x0)2,xi xi–xi is studied in terms of the eigenvalues and eigenfunctions of the Frobenius-Perron operator of the map. It is shown that, near the transition point=2,
i–[(10–42)/17] i,0-[(102-8)/51]i,1 + [(7 + 42)/17](–1)ie–yi, where2(–2) is the damping constant and vanishes at=2, representing the critical slowing-down. This critical phenomenon is in strong contrast to the topologically invariant quantities, such as the Lyapunov exponent, which do not exhibit any anomaly at=2. The asymptotic expression for
i has been obtained by deriving an analytic form of
i for a sequence of which accumulates to 2 from the above. Near the transition point=(2)1/N, the damping constant of
i fori N is given by
N=2(N-2)/N. Numerical calculation is also carried out for arbitrary a and is shown to be consistent with the analytic results. 相似文献
110.
C.L. Duarte M.N. Mori Yasko Kodama H. Oikawa M.H.O. Sampa 《Radiation Physics and Chemistry》2007,76(11-12):1885-1889
The Brazilian agriculture activities have consumed about 288,000 tons of pesticides per year conditioned in about 107,000,000 packing with weight of approximately 23,000 tons. The discharge of empty plastic packing of pesticides can be an environmental concern causing problems to human health, animals, and plants if done without inspection and monitoring. The objective of this work is to study the ionizing radiation effect in the main pesticides used in Brazil for plastic packing decontamination. Among the commercial pesticides, chlorpyrifos has significant importance because of its wide distribution and extensive use and persistence. The radiation-induced degradation of chlorpyrifos in liquid samples and in polyethylene pack was studied by gamma radiolysis. Packing of high-density polyethylene (HDPE) three layer coextruded, named COEX, contaminated with chlorpyrifos, were irradiated using both a multipurpose Co-60 gamma irradiator and a gamma source with 5000 Ci total activity Gamma cell type. The chemical analysis of the chlorpyrifos was made using a gas chromatography associated to the Mass Spectrometry—GCMS from Shimadzu Model QP 5000. Gamma radiation was efficient for removing chlorpyrifos from the plastic packing, in all studied cases. 相似文献