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201.
202.
An adiabatic calorimeter was constructed for heat-capacity measurement between 13.8 and 350 K. The cryogenic temperature was produced by a cryo-refrigerator built into the cryostat. This made it possible to make a prolonged experiment at low temperatures without an external supply of liquid helium or liquid hydrogen. With precautions against possible adverse effects of the mechanical vibration of the refrigerator, the accuracy and precision of the calorimeter as proved by measurements on standard reference benzoic acid were comparable with those of the best low-temperature adiabatic calorimeters. Satisfactory performance of the present apparatus has been demonstrated by detection of a glass transition of CsNO2(c) around 40 K. 相似文献
203.
Yōichi Ishida Masato Matsuo Motowo Takayanagi Fujio Irie 《Colloid and polymer science》1961,175(1):62-63
Ohne Zusammenfassung 相似文献
204.
Matsuo Maeda Sadao Hibi Fumihiro Itoh Shunji Nomura Tatsuro Kawaguchi Hiromichi Kawai 《Journal of Polymer Science.Polymer Physics》1970,8(8):1303-1322
A mathematical representation of the transformation of an orientation function between two sets of Cartesian coordinates is discussed in terms of a series expansion of the distribution function in generalized spherical harmonics. A general procedure for calculating the mechanical anisotropy of a single-phase system (a polycrystalline material) from the orientation of its structural units and the intrinsic mechanical anisotropy of the structural unit is discussed in relation to the transformation of the orientation distribution function, i.e., mutual conversion of the coefficients in the expansion of the distribution function between the two sets of Cartesian coordinates. The procedure is extended to a two-phase systems (semicrystalline polymers) containing structural units composed of crystalline and noncrystalline materials in three different geometrical arrangements. 相似文献
205.
Keietsu Tamagake Yoshiaki Hamada Jun Yamaguchi Akiko Y. Hirakawa Masamichi Tsuboi 《Journal of Molecular Spectroscopy》1974,49(2):232-240
Infrared absorption spectrum of NH2OH has been observed in its gaseous state, and the fine structures of the bands at 386 and 751 cm?1 assignable, respectively, to the fundamental and overtone of the torsional vibration of this molecule have been examined. Band center frequencies for the n = 1 ← 0, 2 ← 1, 3 ← 2, 2 ← 0, and 3 ← 1 transitions (where n is the vibrational quantum number of the torsional oscillation) have been determined to be 386.2, 365.1, 346.3, 751.2, and 711.3 cm?1, respectively. On the basis of these data, a discussion is given on the internal-rotation potential function. 相似文献
206.
Itsuro Matsuo Muneo Ohkido Hitoshi Fujita Kenshi Suzuki 《Photochemistry and photobiology》1980,31(2):175-178
Abstract— When a suspension of Escherichia coli was irradiated with near-UV light in the presence of chlorpromazine (at a concentration below a cytotoxic level), the cells were killed. Efficiency of the photodynamic killing was not influenced by the deficiency of the uvrA gene or the recA gene. Neither phenotypic reversion of E. coli Hs30R (arginine auxotroph) nor induction of lambda prophage in lysogenic bacteria was detected after this treatment. 相似文献
207.
208.
209.
Cyclopalladation occurs for 2-pyridylhydrazones(HL) of p-methyl-, p-methoxy-, p-chloro-, and p-nitro-acetophenone, and 3-acetyl- and 2-acetyl-thiophene with lithium tetrahalopalladate to give the complexes [PdXL] (X = Cl and Br) and some iodo complexes are prepared by metathesis of the chloro complexes with lithium iodide. These complexes are characterized spectroscopically. The hydrazones are coordinated to palladium through benzene or thiophene ortho-carbon, hydrazone-nitrogen, and pyridine ring-nitrogen atoms forming fused five-membered chelate rings. 相似文献
210.
Kiyoaki Kobayashi Takasuke Matsuo Hiroshi Suga Slimane Khairoun Alain Tressaud 《Solid State Communications》1985,53(8):719-722
Heat capacity of ammonium hexafluorovanadate (NH4)3 [VF6] has been measured with a miniaturized adiabatic calorimeter from 20 to 300 K. A phase transition was found at 280.44 ± 0.05 K with the associated entropy change Δtrs S = 24.9 ± 0.5 JK?1 mol?1. The entropy transition is accounted for by the orientational order-disorder changes of hexafluorovanadate ion and ammonium ion occupying respective octahedral sites, as in the cases of (NH4)3AlF6 and (NH4)3FeF6 crystals. Changes in infrared spectra relative to v3 vibrational mode of [VF6]3? ion can be explained by an orientational disorder of the anions in the high-temperature phase (HTP). The dependence of cubic root of the unit-cell volume of a family of ammonium cryolites on their transition temperatures is discussed in relation to the nature of interactions which induce the phase transition. 相似文献