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201.
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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   
203.
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   
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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   
206.
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   
207.
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   
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Coordination self-assembly entities have been demonstrated to be useful and powerful alternatives for the construction of predefined and well-organized architectures. Self-assembled coordination cages, which possess an inner hydrophobic cavity, can be utilized to move substrates closer by encapsulation so enabling their interaction with each other and exhibiting of non-classical physical properties.  相似文献   
210.
Buffer-gas pressure broadening for the (3 0(0) 1)(III)<--(0 0 0) band of CO(2) in the 1600 nm region was investigated with continuous wave cavity ring-down spectroscopy within the temperature range 263-326 K. The measured absorption profiles were analyzed with Voigt functions. Pressure broadening coefficient, gamma(gas), and the temperature dependent parameter (broadening exponent), n, were determined for a variety of buffer gases: N(2), O(2), He, Ne, Ar, Kr and Xe. gamma(air) values estimated subsequently are 0.096(2) for R(0), 0.085(5) for P(8), 0.075(2) for P(16), 0.070(4) for P(26), and 0.069(2) for P(38) in units of cm(-1) atm(-1), where numbers in parentheses are one standard deviation in units of the last digits quoted. n(air) values are 0.77(4) for R(0), and 0.73(11) for P(8).  相似文献   
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