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961.
962.
963.
Mitsuru Ueda Osamu Hara Akira Sato Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1979,17(3):769-775
The aminolysis of benzoic mesitoic anhydride was studied in a model system to select the reaction site by steric effect and was found to occur exclusively at the carbonyl group of the benzoic acid. Solution polycondensation of new linear bisanhydrides, terephthalic bis(mesitoic anhydride) and adipic bis(mesitoic anhydride), with aromatic diamines in polar aprotic solvents that contained lithium chloride at room temperature, afforded polyamides with high molecular weight. The interfacial polycondensation in a dichloromethane-water system also successfully yielded polyamides from aliphatic diamines. 相似文献
964.
Ichiro Noda Toshiaki Kitano Mitsuru Nagasawa 《Journal of Polymer Science.Polymer Physics》1977,15(7):1129-1142
The effect of molecular weight heterogeneity on the second virial coefficient A2 in good solvents is studied for binary mixtures of monodisperse poly(α-methylstyrenes). It is concluded that A2 for polymer mixtures passes through a maximum with variation of the mixing ration. From comparison with the data, it is concluded that no available theory quantitatively explains both the molecular weight dependence of A2 of monodisperse polymer and the variation of A2 of mixtures with the mixing ratio. The interpenetration function for two polymer coils with different molecular weights is discussed on the assumption that the thermodynamic interaction between two polymer coils in good solvents can be approximated by a hard-sphere model. 相似文献
965.
Shizuko Eguchi Machiko Haze Mitsuru Nakayama Shûichi Hayashi 《Journal of mass spectrometry : JMS》1977,12(1):51-52
The predominant elimination of the hydrogen atom or the substituent from the 2′-position in isoflavone derivatives was confirmed by the use of the metastable ion defocusing technique. 相似文献
966.
Yuzuru Niide Mitsuru Takano Takeshi Satoh Yoshiaki Sasada 《Journal of Molecular Spectroscopy》1976,63(1):108-119
The microwave spectra of the two 79Br and 81Br isotopic species of 3-bromopropene were measured in the frequency region 14–23 GHz. The R and Q branches for a- and b-type rotational transitions of one conformer, skew, have been assigned and the rotational constants of the ground state have been determined to be A = 19 247.56 MHz, B = 1975.339 MHz, and C = 1914.761 MHz for 79Br species, and A = 19 234.26 MHz, B = 1961.417 MHz, and C = 1901.563 MHz for 81Br species, respectively. By the analysis of the second-order perturbation treatment of the quadrupole interaction, it is found that the χab element of the χ tensor primarily contributes to the anomalous hyperfine splittings. The matrix elements of products of direction cosines in terms of the symmetric top wavefunctions have been derived. The nuclear quadrupole coupling constants have been determined χaa = 384.2 MHz, χbb = ?71.9 MHz, χcc = ?276.3 MHz, and |χab| = 358.7 MHz for 79Br species and χaa = 283.2 MHz, χbb = ?55.6 MHz, χcc = ?227.6 MHz, and |χab| = 296.0 MHz for 81Br species. 相似文献
967.
Mitsuru Ueda Akira Sato Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1979,17(7):2013-2018
2-Benzothiazolyl benzoate as a model compound was successfully synthesized from the benzoylation of 2-benzothiazolone under kinetically controlled conditions. The aminolysis of 2-benzothiazolyl benzoate afforded excellent yields of N-substituted benzamides at room temperature in a short reaction time. Solution polycondensations of new active diesters, di-2-benzothiazolyl isophthalate and di-2-benzothiazolyl terephthalate, with aliphatic and aromatic diamines, took place rapidly even at room temperature and yielded polyamides with high molecular weight. The high reactivity of 2-benzothiazolyl benzoate was discussed in relation to intramolecular general base catalysis and the tautomeric effect of the benzothiazolone moiety. 相似文献
968.
For commercialization of holographic storage drives, the effects of temperature changes on holographic medium is critical.
There has been no systematic study on the effect of temperature change on hologram recording properties. We believe that the
monomer-diffusion speed and polymerization rate changes are critical for hologram-recording properties and estimate those
parameters on each temperature using the photopolymer medium process simulation we have developed. We describe how these parameters
affect actual recording properties such as sensitivity, M=# and so on. Moreover, we propose a method for compensating temperature changes, and confirm the success of this. 相似文献
969.
Mitsuru Funato Satoshi Aoki Shizuo Fujita Shigeo Fujita 《Journal of Crystal Growth》1997,170(1-4):276-280
We have used atomic force microscopy to investigate the initial stages of the growth of GaAs on ZnSe by metalorganic vapor phase epitaxy. Underlying ZnSe with an atomically flat surface is achieved by growth at 450°C and post-growth annealing at the same temperature. The growth modes of GaAs on the ZnSe surface strongly depend on growth temperatures. The growth carried out at 450°C is 2-dimensional, while that at 550°C is highly 3-dimensional (3D), where the 3D islands are elongated in the [110] direction. The growth behavior, unlike homoepitaxy, is well interpreted in terms of low sticking coefficient and anisotropic lateral growth rate in the heterovalent heteroepitaxy. 相似文献
970.
Takaya Suzuki Yosuke Inoue Mitsuru Ura Takuzo Ogawa Yoshimitsu Sugita 《Journal of Crystal Growth》1978
An in-process monitoring and control method of the doping gas concentration during epitaxial growth of Si was developed. A flame photometric detector (FPD) can be used as a monitor for the PH3 and B2H6 dopant concentrations in the injected doping gases. A combination of this dopant monitor with an automatic control system of the silicon source (SiHCl3) gas concentration using an infrared spectrophotometer as a monitor, makes possible an automatic in-process control of the concentrations of dopant and of silicon source gas supplied to the reactor. The present system provides an accurate and reproducible control of impurity concentrations in Si epitaxial layers. Good correlation between the monitored signal (or the doping gas concentration) and the impurity concentration incorporated into the growth layers was confirmed for PH3 (n-type) and B2H6 (p-type) doping. For the B2H6 doping, a divergence from the linear relationship between the doping gas concentration and the impurity concentration in the layers was observed in the level of acceptor concentration below about 1015 atoms/cm3. The transient response of the present system was measured by growing epitaxial layers with increasing and decreasing step-changes in the dopant gas flow during continuous deposition of the layers. Some interesting, but complicated, transient responses of impurity concentration in the growth layer were observed. The responses are different between the PH3 doping and the B2H6 doping, and also different between increasing and decreasing steps especially for the B2H6 doping. 相似文献