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81.
Frontispiece: Entropy‐Driven 1,2‐Type Friedel–Crafts Reaction of Phenols with N‐tert‐Butoxycarbonyl Aldimines 下载免费PDF全文
82.
Narcisi V Mascini M Perez G Del Carlo M Tiscar PG Yamanaka H Compagnone D 《Talanta》2011,85(4):1927-1932
A post-PCR nucleic acid work by comparing experimental data, from electrochemical genosensors, and bioinformatics data, derived from the simulation of the secondary structure folding and prediction of hybridisation reaction, was carried out in order to rationalize the selection of ssDNA probes for the detection of two Bonamia species, B. exitiosa and B. ostreae, parasites of Ostrea edulis.Six ssDNA probes (from 11 to 25 bases in length, 2 thiolated and 4 biotinylated) were selected within different regions of B. ostreae and B. exitiosa PCR amplicons (300 and 304 bases, respectively) with the aim to discriminate between these parasite species. ssDNA amplicons and probes were analyzed separately using the “Mfold Web Server” simulating the secondary structure folding behaviour. The hybridisation of amplicon-probe was predicted by means of “Dinamelt Web Server”. The results were evaluated considering the number of hydrogen bonds broken and formed in the simulated folding and hybridisation process, variance in gaps for each sequence and number of available bases. In the experimental part, thermally denatured PCR products were captured at the sensor interface via sandwich hybridisation with surface-tethered probes (thiolated probes) and biotinylated signalling probes. A convergence between analytical signals and simulated results was observed, indicating the possibility to use bioinformatic data for ssDNA probes selection to be incorporated in genosensors. 相似文献
83.
Li HH Imai Y Yamanaka M Hayami Y Takiue T Matsubara H Aratono M 《Journal of colloid and interface science》2011,359(1):189-193
To investigate the counterion effects, we employed dodecyltrimethylammonium bromide (DTABr)-dodecyltrimethylammonium tetrafluoroborate (DTABF(4)) mixed aqueous solutions and measured their surface tensions, then analyzed these data in a thermodynamic treatment. The tensiometry showed that DTABF(4) was more effective in lowering the surface tension of water. The phase diagram of adsorption demonstrated that the surface was enriched with BF(4)(-) ions, but the composition of Br(-) ions in the adsorbed film was slightly enhanced compared to the ideal mixing criteria. These were explained in terms of the size and polarizability of counterions. Moreover, the distribution of counterions of the DTABr-DTABF(4) mixtures in the adsorbed film is greatly different from that of the 1-hexyl-3-methylimidazolium bromide (HMIMBr)-1-hexyl-3-methylimidazolium tetrafluoroborate (HMIMBF(4)) mixtures, where a stronger hydrogen-bonding exists between BF(4)(-) and HMIM(+) ions. These findings suggest that the adsorption of counterions in electric double layers is likely subject to two factors: the nature of counterion and their interactions with surfactant ions. 相似文献
84.
Kobayashi K Yamada Y Yamanaka M Sei Y Yamaguchi K 《Journal of the American Chemical Society》2004,126(43):13896-13897
Selective formation of a homo- or hetero-cavitand cage via metal-coordination, by using tetra(4-pyridyl)-cavitand (1), tetrakis(4-pyridylethynyl)-cavitand (2), or tetrakis(4-cyanophenyl)-cavitand (3) as deep cavitand ligands and Pd(dppp)(OTf)2 (4) as a connector, has been investigated by 1H NMR and CSI-MS. When the cavitand and 4 were mixed in CDCl3 in a 2:4 molar ratio, 1 gave a complicated mixture, whereas 2 or 3 formed a homo-cavitand cage {2(2).4[Pd(dppp)]}8+.8(TfO-) (5) or {2(3).4[Pd(dppp)]}8+.8(TfO-) (6), respectively, as a single species. In a 1:1:4 mixture of 2, 3, and 4, homo-cavitand cages 5 and 6 were observed in a 1:1 ratio. In marked contrast, a mixture of 1, 3, and 4 in a 1:1:4 ratio was exclusively self-assembled into a hetero-cavitand cage {1.3.4[Pd(dppp)]}8+.8(TfO-) (7). The selectivity for the self-assembly of the homo- or hetero-cavitand cage via metal coordination would arise from a combination of factors such as coordination ability and steric demand of cavitand ligands. 相似文献
85.
Takayuki Yamanaka Hideki Fukano Ken Tsuzuki Munehisa Tamura Ryuzo Iga Matsuyuki Ogasawara Yasuhiro Kondo Tadashi Saitoh 《光学学报》2003,23(Z1)
A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation. 相似文献
86.
S. Iwama N. Satomi M. Yamanaka S. Goto T. Ishimura H. Ito 《International Journal of Infrared and Millimeter Waves》1981,2(6):1199-1208
A high-power CW 27.972 m water vapor laser has been constructed in order to use as a light source of an interferometer for plasma diagnostics. The laser consists of 220 cm length and 2.0 cm small bore Pyrex glass discharge tube, semi-confocal resonator and Michelson coupler. From the measurement of cavity detuning curves, it is found that two waveguide modes, EH11 and EH21 oscillate. The increase of the output power is found to become more than seven times larger by adding He(50%)–H2(50%) mixed gas. Under the optimum condition, the maximum output power of 65 mW or the output power per unit cavity volume of 83 W/cm3 is obtained. 相似文献
87.
M. Yoshida M. Asano M. Kumakura R. Katakai T. Mashimo H. Yuasa K. Imai H. Yamanaka 《Colloid and polymer science》1990,268(8):726-730
A sequential polydepsipeptide containing a tripeptide sequence L-alanyl-Lalanyl-ethyl L-glutamyl and an-hydroxy acid L-lactic acid, poly(Ala-Ala-Glu(OEt)-Lac), was synthesized to prepare the microspherical particles by the solvent evaporation process. In this case, the solvents play the most important role for the preparation of polydepsipeptide microspheres and, as an example, when 200 mg of the polydepsipeptide dissolved in 10 ml of 98/2% chloroform/dichloroacetic acid mixture was stirred at 400 rpm and 30 C, the microspherical particles with mean diameter of 58m were formed after pouring into 200 ml of 1% (w/v) poly(vinyl alcohol) solution. 17-Estradiol was incorporated into the particles, and the resulting particles were found to contain 5 mg of drug per 25 mg of the particle. The in vivo release of drug from the microspherical formulation was evaluated by measuring the pharmacological influence on rat prostate. It was found that the sufficient amount of drug, keeping the effective pharmacological influence, is supplied during the first 12-week period, followed by an incomplete supplying of drug intil the implant is perfectly degraded in vivo in the 25th week from the start of implantation. 相似文献
88.
89.
Precise temperature and polarization dependences of Raman spectra have been investigated for fully oxygenated twin-free YBa2Cu3O7 single crystals. We have found a striking superconductivity-induced x−y anisotropy in the temperature behavior of the 340 cm−1 line: the magnitudes of the softening and broadening are quite different in the xx-and yy-polarizations. This anisotropy suggests a contribution of the CuO-chain superconductivity with a pairing symmetry different
from that for the CuO2 plane, or indicates that the superconducting gap amplitudes are different in the k
x and k
y directions. The d+s gap symmetry is the only realistic symmetry in the case of Δx≠Δy.
Fiz. Tverd. Tela (St. Petersburg) 40, 403–412 (March 1998)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
90.
We analyze the effects of inelastic scattering on the tunneling time theoretically, using generalized Nelson’s quantum mechanics.
This generalization enables us to describe quantum system with channel couplings and optical potential in a real time stochastic
approach, which seems to give us a new insight into quantum mechanics beyond Copenhagen interpretation 相似文献