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181.
182.
Kazuhiko Hashimoto Hiroshi Sumitomo Shinji Ohsawa 《Journal of polymer science. Part A, Polymer chemistry》1978,16(2):435-445
Equilibrium anionic polymerization of 4,7-dioxaoctanal (DOA) and n-octanal (OA) was carried out in tetrahydrofuran in the temperature range of ?90 to ?68°C, and thermodynamic parameters were evaluated as follows: ΔHss = ?4.0 ± 0.1 kcal/mole, ΔSss = ?18.4 ± 0.5 cal/mole-deg, and Tc,ss = ?56°C for the DOA system; ΔHsc = ?3.4 ± 0.1 kcal/mole, ΔSsc = ?15.7 ± 0.4 cal/mole-deg, and Tc,sc = ?59°C for the OA system. Comparison of these values with those in the cases of β-methoxypropionaldehyde and n-valeraldehyde made it clear that the aliphatic aldehyde having a longer alkyl group polymerizes with smaller changes of enthalpy and entropy and that the polar-substituted aldehydes have higher polymerizability than the corresponding unsubstituted aliphatic aldehydes in the temperature range studied. These effects of substituents are interpreted from the viewpoint of the intermolecular interactions of polar groups in monomers and their polymers. 相似文献
183.
Shinji Nishitani Nobuyuki Kurata Yoshiteru Sakata Soichi Misumi Masahito Migita Tadashi Okada Noboru Mataga 《Tetrahedron letters》1981,22(22):2099-2102
To clarify the primary process of photosynthesis, a series of model compounds, in which an octaethylporphyrin and a benzoquinone ring are connected with different lengths of a polymethylene chain, were synthesized and their photophysical properties were investigated. 相似文献
184.
Professor Shinji Yamashita 《Mathematische Zeitschrift》1975,141(2):139-145
185.
Charge-transfer complexes of TCNQ with ylides, new-type donors, were synthesized and the X-ray photoelectron spectra of these complexes were measured. A broad satellite caused by TCNQ radicals observed. 相似文献
186.
Shinji Yamashita 《Israel Journal of Mathematics》1981,39(3):259-264
Letf be a function holomorphic inU={|z|<1}, and letA(R,f) be the area off(U)∩{|w|<R}, not counting multiplicities. IfA(R,f)=O(R
γ) asR→∞ for a γ, 0≦γ<2, then the subharmonic function exp |f|
p
has a harmonic majorant inU for eachp, 0<p<2−γ. If 0≦γ<1 further, thene
f
is of Hardy classH
p
for eachp, 0<p<∞. 相似文献
187.
188.
A new finite element technique for the analysis of wave run-up is presented in this paper. In this finite element approach, the movement of the shoreline is expressed by that of the nodal points at the wave front, and an auto mesh generation technique is effectively used. The present method is tested by the comparison with the experimental result of a channel with uniform slope, and two numerical examples are reported to show the efficiency of this method. As a final example, the tsunami run-up caused by the 1983 Nihonkai-Chubu earthquake is analysed and compared with actual records of the flooded area. 相似文献
189.
Akira Ishikawa Tomoyuki Ohno Shinji Sakano Yoshihiro Shiroishi 《Journal of magnetism and magnetic materials》1993,120(1-3):357-361
The magnetic properties and crystalline structure of Co alloy film deposited on a regularly corrugated substrate have been studied. Microscopic grooves are lithographically fabricated on InP substrates. In-plane anisotropy energy is 4–5×104J/m3. The magnetic anisotropy is affected by the crystallographic orientation and the microscopic shape of the corrugated Co alloy film. 相似文献
190.
Mitsui M Nagaoka S Matsumoto T Nakajima A 《The journal of physical chemistry. B》2006,110(7):2968-2971
Gas-phase synthesized vanadium-benzene 1:2 (VBz(2)) sandwich clusters were size-selectively deposited onto bare gold and long-chain n-alkanethiolate [-S-(CH(2))(n-1)-CH(3); n = 16, 18, and 22] self-assembled monolayer (SAM)-coated gold substrates under ultrahigh vacuum (UHV) conditions. Investigation of the resulting deposited clusters was performed by infrared reflection absorption spectroscopy (IRAS) and thermal desorption spectroscopy (TDS). The IR frequencies of the soft-landed VBz(2) clusters show excellent agreement with the fundamentals reported in IR data of VBz(2) in an argon matrix. The analysis of IRAS spectra reveals that while there was no orientational preference of the VBz(2) clusters on a bare gold substrate, the VBz(2) clusters deposited onto the SAM substrates were highly oriented with the molecular axis 70-80 degrees tilted off the surface normal. In addition, analysis of TDS spectra revealed unusually large adsorption heats of the physisorbed VBz(2) clusters. The present results are explained by cluster penetration into the long-chain alkanethiolate SAM and for the first time demonstrate the matrix isolation of gas-phase organometallic clusters around room temperature. 相似文献