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71.
Shuzo Hattori Shinzo Morita Masao Yamada Junji Tamano Masayuki Ieda 《Polymer Engineering and Science》1983,23(18):1043-1046
This paper presents the preliminary results of efforts to improve dry processed electron beam resist materials using plasma polymerization coating technology. Three approaches investigated were chemical susceptibility modification, the use of multilayer resist structures, and the effect of grafting reactions. 相似文献
72.
73.
Poly(γ-benzyl L-glutamate) film composed of unusual 7-residue 2-turn (7/2) helices was prepared by slow casting from chloroform solution. The 7/2 helical conformation was irreversibly transformed at 84°C to the normal 18/5 conformation. In d.s.c. thermograms the transformation appeared as an endothermic first order transition with an enthalpy change of 3.4 cal g−1. The viscoelastic and dielectric measurements indicated that the loss peak due to the side chain motion in this film was reduced to a great extent compared to the film of 18/5 helices. The dielectric relaxation strength dictated that there was a motional restriction in three quarters of the side chains. By comparison to a racemic mixture of poly(γ-benzyl glutamate), these anomalous properties were attributed to the stack of terminal benzyl groups of side chains (ormed in an alternating manner between neighbouring chains). The first order transition arises from the cooperative fusion of the stack and the side chains with their benzyl groups which are restricted in thermal motion. Such stacks may be facilitated by the precise ‘knob (side chain) and hole (space between side chains)’ packing which can be attained between neighbouring 7/2 helices. 相似文献
74.
Junji Furukawa 《Polymer Bulletin》1982,7(1):31-37
Summary A theory of pseudo cross-link model suggests the existence of multiple links of various size composed of 116 segmental units. They possesses the heat and entropy of various magnitude giving various transition temperature, TA for the cross-link composed of 4 segments and TB for that of 16 segments. The glass-transition point Tg and the melting point Tm are defined by the different size of lateral multiple links. Relationships, Tm = 2 TA and Tg = (2/3)Tm = (4/3)TA, are derived. A wedge-type relaxation spectrum is obtained as a distribution of size of cross-links. For temperature dependence the WLF-equation is obtained. 相似文献
75.
Heat of mixing for ammonium chloride in liquid ammonia at 25°C was determined in the concentration range 0-50 wt% NH4Cl. It was calculated from the differential heat of solution observed in this work and the differential heat of dilution estimated from activities of solvent. A twin isoperibol calorimeter consisting of two stainless Dewar vessels was used at a relatively high pressure (up to 1.5 MPa). The accuracy of this calorimetry was examined by measuring the heat of solution for tris-(hydroxymethyl)aminomethane(THAM) in 0.1 kmol/m3 HCl at 25°C, and satisfactory agreement within 1.1% between experimental and literature value was obtained. The reproducibility for the experiment was within 2.8%. 相似文献
76.
Morita Shigeru Fujita Junji 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1985,9(4):713-723
X-ray spectra for several elements have been observed from a high-temperature plasma produced in a vacuum spark using a curved-crystal spectrometer. The transition wavelengths of the He-like resonance lines for Ti through Zn are determined for the first time under careful experimental treatments. The result is compared with theoretical predictions. The transition wavelengths of the Fe He-like resonance series lines up to 1s6p–1s2 and the Kβ transition energies of Ti partially M-shell-ionised ions (Ti VI–XIII) are also determined. As a result, several satellite lines are found. 相似文献
77.
Anisotropy of styrene–butadiene rubber (SBR) was investigated. The anisotropy of the copolymer varies linearly with the styrene content and the ultimate value coincides with that of polystyrene at elevated temperature. From these facts, the transverse configuration of the pendant phenyl group is estimated irrespective of the styrene content of SBR. 相似文献
78.
Proton conductive inorganic–organic hybrid membranes were synthesized from styrene derivatives of alkoxysilane and ethyl 2-[3-(dihydroxyphosphonyl)-2-oxopropyl] acrylate (EPA) through copolymerization followed by sol–gel reaction. Self-standing, homogeneous and transparent hybrid membranes with chemically bound phosphonic acid groups were synthesized. FT-IR analysis exhibited the hybrid membranes included phosphonic acid groups. 13C and 29Si NMR studies indicated that alkoxysilyl functionalized styrene derivatives were not only copolymerized with EPA but also condensed yielding Si–O–Si linkages by sol–gel reaction. TG–DTA analysis revealed that these membranes were thermally stable up to 200 °C in dry O2. The proton conductivities of the hybrid membranes increased with phosphonic acid content and temperature. The P/Si ratio of the membrane was dependent on the number of alkoxy group in the starting alkoxysilane. The hybrid membrane from (dimethylmethoxysilylmethyl)styrene (DMMSMS(M))/EPA = 1/6 revealed proton conductivities of 6.3 × 10−3 and 2.4 × 10−4 S cm−1 at 68.0% relative humidity and 18.8% relative humidity, respectively, at 140 °C. 相似文献
79.
Foaming behavior of poly(methyl methacrylate) (PMMA)/multi‐walled carbon nanotubes (MWCNTs) nanocomposites and thermally‐insulating, electrical, and mechanical properties of the nanocomposite foams are investigated. PMMA/MWCNT nanocomposites containing various amounts of MWCNTs are first prepared by combining solution and melt blending methods, and then foamed using CO2. The foaming temperature and MWCNT content are varied for regulating the structure of PMMA/MWCNT nanocomposite foams. The electrical conductivity measurement results show that MWCNTs have little effect on the electrical conductivity of foams with large expansion ratio. Thermal conductivities of both solid and foamed PMMA/MWCNT nanocomposites are measured to evaluate their thermally insulating properties. The gas conduction, solid conduction, and thermal radiation of the foams are calculated for clarifying the effects of cellular structure and MWCNT content on thermal insulation properties. The result demonstrates that MWCNTs endowed foams with enhanced thermal insulation performance by blocking thermal radiation. Moreover, the compressive testing shows that MWCNTs improve the compressive strength and rigidity of foams. This research is essential for optimizing environmentally friendly thermal insulation nanocomposite foams with enhanced thermal‐insulation and compressive mechanical properties. 相似文献
80.
An extreme ultraviolet spectrometer has been developed for spectroscopic studies of highly charged ions with an electron beam ion trap. It has a slit-less configuration with a spherical varied-line-spacing grating that provides a flat focal plane for grazing incidence light. Alternative use of two different gratings enables us to cover the wavelength range 1-25 nm. Test observations with the Tokyo electron beam ion trap demonstrate the high performance of the present spectrometer such as a resolving power of above 1000. 相似文献