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61.
T. Yonezawa H. Kikuchi K. Hayashi N. Tochizawa N. Endo S. Fukuzawa S. Sugito K. Ichimura 《Polymer Engineering and Science》1989,29(14):898-901
Many styrylpyridinium compounds (SPC), which are very stable in the dark, were prepared and evaluated as photobleachable dyes for contrast enhanced lithography (CEL). The photobleaching characteristics of water-soluble contrast enhancing materials composed of SPC and water-soluble polymer depend on the structure of the SPC and the kind of polymers used. The technique using SPC-based CEL proved to be very effective for the resist pattern profiles. 相似文献
62.
To evaluate the intraparticle diffusion coefficient, De, of a component in a liquid, it was assumed that the pore structure of a porous catalyst was a space between an assembly of fine particles. This structure has been found for the metal oxide catalysts. The diffusivity ratio, δ (= De/D), was geometrically estimated in the direction normal to the representative plane (100), (110) or (111) of cubic closed, body centered cubic, simple cubic, or diamond packing of spherical elementary particles. The value δ was found to approximate the porosity ?. Larger pore constrictions gave smaller δ/? values. Reaction rates were measured for the hydrogenation of nitrobenzene in ethanol. The efficiency of this evaluation of De was supported by the agreement of the experimental effectiveness factor with the theoretical factor. 相似文献
63.
Toshihiro Hirotsu Kunihiro Ichimura Kensaku Mizoguchi Eiichiro Nakamura 《应用聚合物科学杂志》1988,36(8):1717-1729
Water–ethanol permselectivity was investigated by pervaporation through composite membranes which were prepared by coating photocrosslinkable poly(vinyl alcohol) containing pendant styrylpyridinium group (0.86–3.93 mol %) on porous films. These membranes were water-permselective, and the selectivity was dependent on the state of membranes; namely, incorporation ratio of styrylpyridinium group on poly(vinyl alcohol), molecular weight of the base polymer, coating thickness of a photopolymer, etc. Photocrosslinkable styrylpyridinium group showed, of course, the ionic character by a pyridinium moiety to work on permseparation of water effectively as well as preventing the dissolution of membranes by crosslinking. Membranes based on the higher molecular weight poly(vinyl alcohol) (P = 1700) gave the higher permselectivity of water in general than those of lower molecular weight (P = 500) one. Swelling of the polymers reached 160%, and permeation rate through the membranes increased with the increase of swelling. Selective diffusion of water was found to take place in swelling, and to play a part in the water-permseparation through the membranes. 相似文献
64.
Jun-Ichi Kawabata Midori Yumiyama Yoneshiro Tazaki Senji Honma Shohei Takeda Hiroshi Yamaguchi Tadatoshi Chiba Kunio Yoshida 《Chemical Engineering Communications》1981,11(6):335-345
A two-stage pressurized fluidized-bed gasification process has been developed to produce low-heating value gases from coal char. The reactor was 0.075 m id. and 1.4 m long, and gasification experiments were conducted under pressures up to 790 kPa and at temperatures up to 1323 K. A partition disc was used to divide the fluidized bed into two stages, using the first stage as a partial combuster and gasifier and the second stage as a gasifier. The disc was designed to control compositions of coal char particles in both stages so that the heat required for the endothermic gasification reaction in the second stage can be provided by the heat of combustion in the first
For conditions examined here, the disc with an opening ratio of 40° was found to give optimum distribution of the char particles in both stages without ash agglomeration. It was also shown that all oxygen gas was completely consumed within the first stage
The heating value of the product gas increased with the char feed rale. However, there may be an oplimum Teed ratio of char and sand-particles since the higher char feed rate causes more frequent ash agglomeration as well as less carbon conversion 相似文献
For conditions examined here, the disc with an opening ratio of 40° was found to give optimum distribution of the char particles in both stages without ash agglomeration. It was also shown that all oxygen gas was completely consumed within the first stage
The heating value of the product gas increased with the char feed rale. However, there may be an oplimum Teed ratio of char and sand-particles since the higher char feed rate causes more frequent ash agglomeration as well as less carbon conversion 相似文献
65.
Shigeyuki Smiya Masahiro Yoshimura Shutaro Fujiwara Ken-Ichi Kondo Akira Sawaoka Takeo Haitori Jun-Ichi Mohri Masatada Araki 《Journal of the American Ceramic Society》1984,67(3):51-C-
To enhance the sinter ability of Si3 N4 , powders mixed with 0, 2, and 5 wt% Y2 O3 were explosively shock-treated. Compacts of these powders were encapsulated in 96% silica glass containers and isostatically hot-pressed. The shocked Si3 N4 with 5 wt% Y2 O3 was pressed to a density of 3.09 g/cm3 (95.4% of theoretical) at 1400°C under 430 MPa for 3 h, whereas the unshocked material attained only 82.4% of theoretical density under the same hot isostatic pressing conditions. 相似文献
66.
Abstract The T value represents the HOMO-LUMO energy separation of a ?-electronic system weighted with the number of conjugated atoms. We found that this value is kept almost constant for the polyene references defined graph-theoretically for isolated-pentagon isomers of fullerenes with up to 100 carbon atoms. on this numerical basis, the T value can safely be considered as a realistic index of kinetic stability or chemical inertness for all fullerenes without abutting pentagons. 相似文献
67.
Yukio Fujiwara Naoaki Saito Hidehiko Nonaka Taisuke Nakanaga Shingo Ichimura 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(11-12):1938-1941
Electrospray characteristics were studied using a pure room-temperature molten salt (i.e., an ionic liquid) at pressures around 10?5 Pa as well as at atmospheric pressure. The ionic liquid N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide was tested, which has negligible vapor pressure and high conductivity. During electrospray, the ionic liquid was introduced at a constant flow rate into a stainless-steel capillary (i.d. 30 μm). It was demonstrated that stable electrosprayed currents exceeding ±1 μΑ were continuously produced in both positive and negative modes. The electrosprayed currents in a high vacuum were twice those at atmospheric pressure. It was found that gas pressure rose slightly with increasing electrosprayed currents. Residual gas analysis revealed that gas component at negative mode was different from that at positive mode. Experimental results indicate that vacuum electrospray of pure ionic liquids is applicable to a massive-cluster beam source for SIMS. 相似文献
68.
CdS/SnS and Cd1−xZnxS/SnS solar cells were fabricated. SnS films were deposited by the pulsed electrochemical deposition method using an aqueous solution containing SnSO4 and Na2S2O3. CdS and Cd1−xZnxS window layers were deposited by using the photochemical deposition method using an aqueous solution containing CdSO4, ZnSO4 and Na2S2O3. Both the techniques were simple, economical and advantageous for fabricating cheap solar cells. The fabricated cells showed rectification characteristics. The photovoltaic properties were measured under AM 1.5 illumination. The cells with the Cd1−xZnxS window layer show larger photocurrent than those with the CdS window layer. 相似文献
69.
Ouji Y Yoshida-Terakura A Hayashi Y Maeda I Kawase M Yamato E Miyazaki J Yagi K 《Journal of Bioscience and Bioengineering》2002,94(1):81-83
In search of an efficient nonviral vector, polyethyleneimine (PEI)-based vectors were examined. In general, the transfection efficiency of nonviral vectors is suppressed by serum. Here we show that PEI based vectors, particularly, the chitosan hexamer-PEI vector, could perform efficient gene transfection into intestinal epithelial cells (IEC-6) in the presence of serum. The conjugation order of the two polymers with a plasmid (first, chitosan hexamer; second, PEI) was found to be an important factor in enhancing transfection efficiency. 相似文献
70.
In this paper we concentrate on spatial prepositions, more specifically we are interested here in projective prepositions (eg. in front of, to the left of) which have in the past been treated as semantically uninteresting. We demonstrate that projective prepositions are in fact problematic and demand more attention than they have so far been afforded; after summarising the important components of their meaning, we review the deficiencies of past and current approaches to the decoding problem; that is, predicting what a locative expression used in a particular situation conveys. Finally we present our own approach. Motivated by the shortcomings of contemporary work, we integrate elements of Lang's conceptual representation of objects' perceptual and dimensional characteristics, and the potential field model of object proximity that originated in manipulator and mobile robot path-finding. 相似文献