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161.
Masumi Inoue Kenji Yoshida Kazushige Ohbayashi Yoshiaki Takai Hisao Hayakawa 《Physica C: Superconductivity and its Applications》1992,200(3-4):403-408
We have prepared Bi2Sr2CaCu2Ox/Bi2Sr2CuOx (2212/2201) superlattices with various stacking periodicity by multitarget RF magnetron sputtering. Their crystal structure and electrical properties were investigated. The superlattice was found to be successfully constructed from the data of XRD patterns, AES, etc. The critical temperature increased almost linearly with increasing thickness of the 2212 phase up to a thickness of 6 unit cells. On the other hand, it did not decrease as the thickness of the 2201 layers was increased. The unit cell/unit cell superlattice showed Tc zero of 30 K. 相似文献
162.
A symmetry rule for the sign of Cotton effect of β,γ-unsaturated ketnoes in n → π* region has been proposed and this rule can correctly predict the sign of c.d. even for the ketones to which the generalized octant rule could not be applied. 相似文献
163.
Masumi Sato 《等离子体物理论文集》1971,11(6):445-459
Moving striations in the tapered tube with smoothly changing radius are studied experimentally. The frequency depends on local tube radius by nature and increases toward the narrow end of the tube, independent of direction and magnitude of the discharge current. Radius-frequency versus radius-pressure is compatible with the similarity law for striations in cylindrical tubes. When there appears synchronization, the frequency becomes apparently constant throughout the tube column. The wavelength shows different dependences on radius without and with the synchronization. An important role is played by the feedback through an electric circuit. Also, direction and magnitude of the current have influence on the phenomena. Steady states in the tubes are compared with those in cylindrical tubes. An attempt is made to explain the observed synchronizations and then the remarkable discrepancies between the previous experiments can be eliminated. 相似文献
164.
The substituent effect on the integrated intensities of the characteristic CN infrared band of benzonitrile derivatives was studied using the CNDO/2 method. The charge flux term plays an important role in the substituent effect on the intensities and the fixed charge term does not have a predominant effect on the intensities. The contributions of the π,
, and σ electron systems to the charge flux term are discussed in detail. 相似文献
165.
Effect of wood properties on within-tree variation in ultrasonic wave velocity in softwood 总被引:2,自引:0,他引:2
The radial variations in the velocity of longitudinal waves propagating through Japanese cedar and Japanese cypress were experimentally investigated. In addition, the tracheid length (TL), microfibril angle (MFA), air-dried density (AD), and moisture content (MC) were measured in order to determine the effect of wood properties on velocity variations within the wood trunk. For both species, the longitudinal wave velocities measured in the longitudinal direction (VL) exhibited minimum values near the pith. For Japanese cedar, VL increased from 3600 m/s toward the bark and soon attained a constant value (=4500 m/s). On the other hand, for Japanese cypress, VL kept increasing from 4000 m/s near the pith to 4800 m/s at the bark. These radial variations in VL coincided with those in the tracheid length. VL exhibited strong correlations with TL and MFA with a significant level of (p < 0.01). These findings suggest that the TL and MFA greatly affect the radial variation in the ultrasonic wave velocity in softwood. 相似文献
166.
Hydrodynamic control of droplet division in bifurcating microchannel and its application to particle synthesis 总被引:1,自引:0,他引:1
Yamada M Doi S Maenaka H Yasuda M Seki M 《Journal of colloid and interface science》2008,321(2):401-407
We describe herein a microfluidic system for active and precise control of droplet division at a bifurcation point in a microchannel. Water-in-oil or oil-in-water droplets, which were initially formed at a T-junction, were introduced into the bifurcation point, and then divided into two daughter droplets. By continuously introducing 'tuning flow' into the downstream of one of the branch channels, and by controlling the flow rates distributed into the two branch channels, the sizes of the daughter droplets could be precisely tuned. The ratio of the volumetric flow rates into the branch channels was estimated by regarding the microchannel network as a resistive circuit. In addition, we performed synthesis of monodispersed polymer particles with controlled sizes utilizing the presented system. The ability to hydrodynamically control the droplet sizes will open new possibilities not only for producing useful emulsions, but also for conducting controlled chemical and biochemical reactions in a confined space. 相似文献
167.
Alkyl chain length dependence of the self-organized structure of alkyl-substituted phthalocyanines 总被引:1,自引:0,他引:1
Miyake K Hori Y Ikeda T Asakawa M Shimizu T Sasaki S 《Langmuir : the ACS journal of surfaces and colloids》2008,24(9):4708-4714
The alkyl chain length on alkyl-substituted phthalocyanines (C(n)OPc) dependence of their self-organized structures was examined in this study. STM results indicated that the symmetry of ordered structures decreased as the alkyl chain became longer, with the exception of C(6)OPc, which preferentially formed a quasi-3-fold symmetrical structure. This could be explained by the fact that the C(n)OPc molecules are most likely to form densely packed structures. With C(n)OPc, when n = 4 to 10, the self-organized structures were dependent on the competition between how densely the molecules were arranged and how loose the intermolecular interaction energy was, caused by the formation of the densely packed structure. However, with C(n)OPc, when n = 10-18, the molecules tended to form densely packed structures by reducing the symmetry, even though the C(n)OPc molecules were distorted. When C(12)OPc and cobalt phthalocyanine were coadsorbed, the mixed system exhibited a four-fold symmetrical structure, which is rarely observed in C(12)OPc. 相似文献
168.
Sun K Suzuki N Li Z Araki R Ueno K Juodkazis S Abe M Noji S Misawa H 《Electrophoresis》2008,29(19):3959-3963
A microchannel chip has been used to fractionate selected segments from an electrophoretic flow of separated fragments. A sample, which covers the size from 35 to 670 bp, was initially separated using an 8.8-cm-long channel at the electric field strength of 100 V/cm. The target fragment of 318 bp was selected and extracted from the separation channel. High-resolution fractionation was achieved by introducing new procedures for blocking, extraction, and segment transfer. Fractionation quality with and without blocking were compared using a 310 Genetic Analyzer (Applied Biosystems). The results show that no contamination was found in the sample, which was fractionated with blocking; however, a contamination by short segments was found in the sample, which was fractionated without blocking. Furthermore, fractionation by the chip was found to be of higher fidelity than that by the polyacrylamide slab gel, which displayed a small overlapped peak after the target peak. Compared with the traditional method, our chips enable faster and high-fidelity fractionation, thus providing a new tool for bioanalysis and other applications. 相似文献
169.
Arai T Horiguchi M Yanagida M Gunji T Sugihara H Sayama K 《Chemical communications (Cambridge, England)》2008,(43):5565-5567
Acetaldehyde was completely oxidized to CO(2) over a Pd/WO(3) photocatalyst under fluorescent-light irradiation in a flow-type reactor, and Pd/WO(3) was also used to completely oxidize toluene to CO(2) in a batch reactor under visible-light irradiation. 相似文献
170.
Otsuki J Kawaguchi S Yamakawa T Asakawa M Miyake K 《Langmuir : the ACS journal of surfaces and colloids》2006,22(13):5708-5715
Three double-decker complexes of cerium(IV) were synthesized, which commonly have a 5,10,15,20-tetrakis(4-docosyloxyphenyl)porphyrin (C22OPP) moiety as one of the two tetrapyrrole rings. The three complexes-Ce(Pc)(C22OPP), Ce(C22OPP)2, and Ce(BPEPP)(C22OPP)-are distinguished by the other rings, which are Pc (=phthalocyanine), C22OPP, and BPEPP (=5,15-bis[4-(phenylethynyl)phenyl]porphyrin), respectively. The rate of inter-ring rotation of Ce(BPEPP)(C22OPP) was estimated to be approximately 3 s(-1) in solution at room temperature. These complexes assemble into ordered arrays at the interface of 1-phenyloctane and the highly oriented pyrolytic graphite surface, owing to the affinity of the long alkyl chains toward the surface, as revealed by means of scanning tunneling microscopy (STM) with molecular resolution. The shape of the upper ring is reflected in the STM image. Thus, Ce(Pc)(C22OPP), Ce(C22OPP)2, and Ce(BPEPP)(C22OPP) were observed as circular, square, and elliptic features, respectively. Possible molecular arrangements in the array of Ce(BPEPP)(C22OPP) are proposed by comparing STM images and molecular models. In the mixed arrays of Ce(BPEPP)(C22OPP) and H2(C22OPP), the double-decker complexes were distinguished by brighter features. Competitive adsorption experiments showed that the adsorption of Ce(BPEPP)(C22OPP) is less favorable than that of H2(C22OPP) by DeltaG(app) = 2.7 kJ mol(-1). Ce(BPEPP)(C22OPP) molecules appeared elliptic when placed within their own row, while they appeared isotropic when flanked by H2(C22OPP) molecules. Implications of the differences in the observed shapes to the inter-ring rotation are discussed. 相似文献