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81.
Hitoshi Masuda Chiyoshi Kamizawa Kunio Hata Kingo Yokota Tomoo Sakai Mitsuhiro Sato 《Desalination》1978,25(1):89-97
The evaporation drain of sulfite pulp spent liquor contains few volatile fatty acids, most of which is acetic acid. The main objective of this study is to recover acetic acid as the concentrated solution (about 4%), which could be used as a culture medium of the yeast. As acetic acid can easily pass through the cellulose acetate membrane, SP drains neutralized by NaOH, NH4OH and Ca(OH)2 were used as the feed solutions. In all cases, concentration by reverse osmosis was successfully carried out provided the appropriate pretreatment was employed. The recovery of acetic acid was 95.6, 90.5 and 98.2% for Na-, NH4-, and Ca-drain, respectively. In addition, the recovered (permeated) water may be used as an industrial one. 相似文献
82.
A technique for separating similar and diverse ionogenic mixtures into their individual homologs was studied by high performance
liquid chromatography on an octadecyl-silica (TSK Gel LS-410) column. Conditions used for the separation were: column size,
6 mm id×200 mm; mobile phase, water/methanol (15:85, v/v) containing (a) 1.0 M sodium perchlorate and adjsting to pH 2.5 with
phosphoric acid, (b) 0.1 M and pH 3.5; column temp., 50 C. By using 2 mobile phase conditions, various surfactant mixtures
were separated into their individual homologs and simultaneously distinguished from each other, regardless of their ionogenic
properties. 相似文献
83.
Somsak Vivatpanachart Hiroyasu Nomura Yutaka Miyahara Hisatsugu Kashiwabara Masato Sakaguchi 《Polymer》1981,22(7):896-901
E.s.r. spectra of chain-end spin labels on the surface of polyethylene powder were obtained for high and low density polyethylene samples at various stages of heat treatment process. The subsequent crystalline structures of the samples were examined with wide angle and small angle X-ray diffraction spectra. The effects of annealing on the motion of the labels were dependent on annealing temperature and the type of the samples. Higher temperature annealing decreased the rotational correlation times (τc) and their activation energy in high density polyethylene but did not affect those of low density polyethylene. Melting decreases the values of τc and ΔE for both high an low density polyethylene samples. The cause of these decreases were attributed to the changing of the sites of the chain-end labels. The motion of the labels appeared to be influenced by the local segmental motion of the polymer main chains. 相似文献
84.
A decomposition algorithm for scheduling problems based on timed automata (TA) model is proposed. The problem is represented as an optimal state transition problem for TA. The model comprises of the parallel composition of submodels such as jobs and resources. The procedure of the proposed methodology can be divided into two steps. The first step is to decompose the TA model into several submodels by using decomposable condition. The second step is to combine individual solution of subproblems for the decomposed submodels by the penalty function method. A feasible solution for the entire model is derived through the iterated computation of solving the subproblem for each submodel. The proposed methodology is applied to solve flowshop and jobshop scheduling problems. Computational experiments demonstrate the effectiveness of the proposed algorithm compared with a conventional TA scheduling algorithm without decomposition. 相似文献
85.
Joo-Young Lee Yota Yamamoto Riichi Oe Su-Young Son Hitoshi Wakabayashi Yutaka Tochihara 《Ergonomics》2014,57(8):1213-1221
The purpose of this study was to investigate the physiological and subjective responses of the European, Japanese (JPN) and US firefighters' helmet, gloves and boots for international standardisation. Three experimental conditions were evaluated (clothing mass: 9.4, 8.2 and 10.1 kg for the three conditions, respectively) at the air temperature of 32°C and 60% relative humidity. The results showed that there was no significant difference among the three conditions in oxygen consumption, heart rate, total sweat rate, rectal temperature and mean skin temperature, whereas peripheral temperatures and subjective perceptions were lower in the JPN condition than in the other conditions (P < 0.05). These results indicate that a 0.5-kg reduction in helmet mass and a 1.1-kg reduction in boot mass during exercise resulted in a significant decrease in head and leg temperatures and subjective perceptions, while a 1.9-kg reduction in total clothing mass had insignificant influences on the metabolic burden and overall body temperature. 相似文献
86.
S-menthyloxycarbonylmethyl l- and d-cysteines were prepared by the reaction of l- or d-cysteine and (?)-menthyl chloroacetate in liquid ammonia and were then polymerized to poly(S-menthyloxycarbonylmethyll- and d-cysteines) by the N-carboxyanhydride (NCA) method. From the results obtained by means of infra-red spectra, X-ray diffractions, optical rotatory dispersions (o.r.d.), and circular dichroisms (c.d.), was found to be a right-handed α-helix in the solid state and in ethyl ether/chloroform and chloroform solutions. Similarly, was a left-handed α-helix. The helix-coil transition of these polymers was observed in the vicinity of 3–4% trifluoroacetic acid (TFA) in chloroform/TFA mixtures. 相似文献
87.
Masashi Wada Satoshi Kitaoka Naoki Kawashima Tatsuya Yamada Yoshiyuki Yasutomi Masatoshi Kawai Hideki Inagaki 《Journal of the American Ceramic Society》2006,89(7):2134-2139
Carbon substrates were coated completely with a molten silicate glass, where the wettability of carbon to glass was improved by infiltration and pyrolysis of perhydropolysilazane. Microstructures of the carbon–glass interface were dependent on P n 2 during coating. Coating at lower P n 2 induced the formation of cristobalite at the carbon–glass interface. When the coating was performed at higher P n 2 , the glass and carbon were strongly adhered, without the formation of cristobalite. Coating at higher P n 2 improved the thermal shock resistance of the glass layer, because crack initiation was not induced by the phase transformation of cristobalite during the cooling process. In the case of coating at higher P n 2 , an oxynitride glass layer was formed at the glass subsurface by dissolution of N2 . A porous glass subsurface layer with uniform spherical micro-pores could be produced by soaking near the glass transition temperature in a steam environment. The porous layer with fine and homogeneous microstructure acts as a thermal shock absorbing layer, so that glass-coated carbon with a porous glass layer has excellent thermal shock resistance in addition to steam oxidation resistance. 相似文献
88.
Yoshitsugu Kosugi Tsutomu Kunieda Naoki Azuma 《Journal of the American Oil Chemists' Society》1994,71(4):445-448
Rice bran oil containing 30–50% free fatty acid was continually converted to an oil containing more than 75% of triacylglycerol
(TG) by means of immobilized lipase. The reaction was carried out at 60°C for 24 h with dehydration and reactant mixing by
dry nitrogen flow under a positive nitrogen atmosphere. Enzymatic TG synthesis with evaporation by heating was not suitable
because of the increasing peroxide value of the oil.
Part of this article was presented at the annual meeting of the Japan Oil Chemists' Society at Sendai, Japan, October, 16,
1990. 相似文献
89.
Jinhua Chen Upita Septiani Masaharu Asano Yasunari Maekawa Hitoshi Kubota Masaru Yoshida 《应用聚合物科学杂志》2007,103(3):1966-1972
In this study the fluoropolymers, poly(ethylene‐co‐tetrafluoroethylene) (ETFE) and poly(vinylidene fluoride) (PVDF) films, together with the radiation‐induced crosslinked polytetrafluoroethylene (cPTFE) film were compared on the basis of their preparation and properties of radiation‐grafted polymer electrolyte membranes. The polymer electrolyte membranes were prepared by radiation grafting of styrene into the base films and subsequent sulfonation. The proton conductivity and chemical stability of the three types of membranes with a similar ion exchange capacity (IEC) near 1.0 mmol/g were investigated and are discussed in detail. Although the ETFE‐based polymer electrolyte membrane was relatively more stable, its proton conductivity was lower than those of the PVDF‐ and cPTFE‐based membranes. On the other hand, the cPTFE‐based membrane showed a significantly higher proton conductivity, but its chemical stability was shorter than that of the ETFE‐based membrane. It is considered that the difference in the preparation and properties of the polymer electrolyte membranes was due to the difference in the degree of crystallinity as well as in the chemical structure of the fluoropolymer base films. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1966–1972, 2007 相似文献
90.
Zhe-Feng Zhang Zheng Ming Sun Hitoshi Hashimoto Toshihiko Abe 《Journal of the American Ceramic Society》2003,86(3):431-436
Ti/Si/2TiC powders were prepared using a mixture method (M) and a mechanical alloying (MA) method to fabricate Ti3 SiC2 at 1200°–1400°C using a pulse discharge sintering (PDS) technique. The results showed that the Ti3 SiC2 samples with <5 wt% TiC could be rapidly synthesized from the M powders; however, the TiC content was always >18 wt% in the MA samples. Further sintering of the M powder showed that the purity of Ti3 SiC2 could be improved to >97 wt% at 1250°–1300°C, which is ∼200°–300°C lower than that of sintered Ti/Si/C and Ti/SiC/C powders using the hot isostatic pressing (HIPing) technique. The microstructure of Ti3 SiC2 also could be controlled using three types of powders, i.e., fine, coarse, or duplex-grained, within the sintering temperature range. In comparison with Ti/Si/C and Ti/SiC/C mixture powders, it has been suggested that high-purity Ti3 SiC2 could be rapidly synthesized by sintering the Ti/Si/TiC powder mixture at relatively lower temperature using the PDS technique. 相似文献