KAGAKU KOGAKU RONBUNSHU
Online ISSN : 1349-9203
Print ISSN : 0386-216X
ISSN-L : 0386-216X
Volume 23 , Issue 2
Showing 1-38 articles out of 38 articles from the selected issue
  • Eiji Nakanishi, Seizou Isobe, Takeichiro Takamatsu, Hiroaki Yasuoka, H ...
    1997 Volume 23 Issue 2 Pages 137-142
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    When rcycling of disposed plastics products is investigated using LCA, the environ-mental assessment for recycling depends on how to specify its enviromental load. In view of promoting the recycling of disposed plastics products such as PET bottles after use, it has been concluded to be reasonable that the cumulative CO2 emission unit defined as one of the environmental load indices for carbon dioxide should be specified as zero for disposed plastics products.
    Using the concept of cumulative CO2 emission units, the recycling of disposed PET bottles has been studied as a LCA problem and the following two conclusions have been confirmed. First, when the PET bottles are incinerated in open loop recycling, the latent energy of the petrochemicals is recovered while a large amount of CO2 is emitted to the atmosphere. Second, the use of recycled PET pellet contributes to decrease cumulative CO2 emission units in the production of carpet compared to the case where the virgin PET pellet is used.
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  • Yasuo Hatate, Kenji Mitsudome, Yoshimitsu Uemura, Ryoko Aikoh, Masanor ...
    1997 Volume 23 Issue 2 Pages 143-148
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Murphree stage efficiencies of minute components (n-propyl alcohol and iso-butyl alcohol) in ethanol aqueous solution were determined by using a 10-stage Oldershow type rectification column. By employing the azeotropic operation of ethanol-water systems, constant equilibrium ratios of the minute components were realized throughout all stages of the column to obtain the precise values of the Murphree Stage efficiencies. The following results were obtained;
    1) Murphree stage efficiencies for both minute components were almost the same and decreased from 0.80 to 0.65 when decreasing the pressure from 101.3 to 12.7 kPa.
    2) The same results were obtained for periodic and continuous reflux operations to confirm that the laboratory scale data obtained by periodic reflux would be applicable to industrial scale situations.
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  • Akira Saji, Yukihiro Takamura, Hidetomo Noda, Fujio Watanabe, Hitoki M ...
    1997 Volume 23 Issue 2 Pages 149-156
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The application of pressure swing adsorption (PSA) method to CO2 separation from Hue gas was examined. The main process was comprised of PSA and a super cold separator. Carbon dioxide, which present in about 10% concnetration in flue gas, was initially concentrated by PSA, and then the concentrated CO2 was liquefied by the super cold separator (condenser) up to a concentration of more than 99%. The objectives of this study were (1) to make clear the effect of absorbent on the PSA performance, and (2) to make clear the suitable PSA operation condition with high CO2 concentration and its high recovery.
    In this study, a zeolite 13X adsorbent in the PSA system was useful for CO2 separation from artificial flue gas. By optimization of PSA operation conditions, the product from PSA showed a CO2 concentration of ca.70%and recovery was more than 90%.In addition, the final product of the process showed CO2 concentration of ca. 99% and recovery of ca.90%, when the off-gas from the condenser was introduced into the inlet of PSA and the operation conditions of the process were optimized.
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  • Minobu Ono, Norio Sato, Masafumi Kuriyama, Hideki Tokanai, Hirotaka Ko ...
    1997 Volume 23 Issue 2 Pages 157-162
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    An experimental study was carried out for the dispersion of highly viscous drops in a practical 50-liter agitated vessel equipped with a pitched backswept turbine with perforated disc to obtain some information about emulsification processes in the dairy industry. As a result, the data of final and transient drop sizes were given under several operating conditions, being expressed well by the respective correlation equations which had been proposed by the authors for a laboratory-scale agitated vessel with a Rushton turbine.
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  • Makoto Kohga, Yutaka Hagihara
    1997 Volume 23 Issue 2 Pages 163-169
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    In order to prepare Ammonium Perchlorate (AP) composite propellant with a high burning rate, fine AP, of which mean diameter is less than 10 × 10-6 m, is required. In this study, an attempt was made to prepare fine spherical AP with safety through a freeze-drying method. O/W emulsion was prepared by emulsifying with organic solvent as dispersed phase and AP solution as dispersion medium. Organic solvents used in this study barely dissolve AP and water. The emulsion was frozen with liquid nitrogen and the frozen emulsion was freeze-dried. The mean diameter (Dav [m]) of AP prepared depends on the interfacical tension (σ [N-m-1]) between organic solvent and AP solution. In the case of 0.5 × 10-2 N · m-1 ≤σ 4.9 × 10-2 N · m-1, the relationship between Day and a is expressed by the following equation.
    Dav=0.18σ×10-3
    The addition of surface active agents is effective for a decrease in σ. However, foam formed on the emulsion during the preparation for all of the organic solvents used in this study except toluene. Consequently Dav deviated from the above equation and there was little spherical AP present. It was proved that the freeze-drying method is applicable as a safe preparation method for fine spherical AP.
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  • Yoshitomo Hanakuma, Kazutoyo Nakaya, Takeshi Takeuchi, Takashi Sasaki, ...
    1997 Volume 23 Issue 2 Pages 170-174
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    A method of setting the threshold is said to be difficult for detecting abnormal signals in fault diagnosis. In this paper, a method of detecting abnormal signals using hypothesis testing for residual sequence of AR model estimation error by recursive maximum likelihood method was studied. It involves F-testing the difference between present and past unbiased variance and t-testing the difference between present and past mean for residual sequence of AR model estimation error.
    The method was applied to abnormal detection of the catalyst feed flow in a linear low-density polyethylene plant to confirm the design philosophy. The actual result indicates that the F-testing method is effective in detecting abnormal process signals.
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  • Masahito Nakagami, Masaru Ishida
    1997 Volume 23 Issue 2 Pages 175-180
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    We propose the following genetic algorithms (GA) to effectively solve job-shop scheduling problems by introducing the following judgments of the present status of the genes in the population and characteristics of the task sequence : (1) Extracting excellent genes, i.e., the effective part in the string from individuals with good fitness ; (2) Exploiting local search around an elite by checking all probable mutation within one Hamming distance ; (3) Introducing an overrule to examine only the cases which seem to give good results.
    These algorithms are tested by applying them to the Muth-Thompson Job-Shop Scheduling Problems (1963), and we prove that the application of GA with combined use of these algorithms can generate practically good schedules even for job-shop scheduling problems of relatively large scale.
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  • Yuichi Ohira, Hiroshi Takahashi, Koji Ando
    1997 Volume 23 Issue 2 Pages 181-187
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Effects of the gas velocity and the ratios of outer/inner column diameter on the values of local gas holdup in a double tube bubble column were experimentally studied. The local gas holdup in the annular section was measured by means of a conductivity probe technique. The maximum value in the radial profile of gas holdup and the mean gas holdup increased with increasing superficial gas velocity, while they were hardly affected by the ratios of outer/inner column diameter within the range of the present experiment. Based on the velocity profile of fluid in laminar flow, modeling the gas holdup profile in the annular section was carried out. The results calculated by the experimental equation agreed well with the measured data for the radial profiles of the gas holdup.
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  • Kazunori Tsurumi, Katsutoshi Inoue
    1997 Volume 23 Issue 2 Pages 188-193
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Usually, platinum supported on zeolite catalyst is applied as a pelletized form from Pt-zeolite powder which is prepared by calcination and reduction of [Pt (NH3) 4] ion supported on zeolite powder by ion exchange method. In this study, platinum was supported onto pre-pelletized zeolite by an ion exchange method using tetraammineplatinum (II) dichloride and hydroxopentaammineplatinum (IV) trichloride, hereafter referred to simply as Pt (II) ammine and Pt (IV) ammine, and their adsorption behavior and catalytic activity were compared.
    A substantial difference in the distribution of platinum into the pellets was observed between the platinum ammine complex ion species. Pt (IV) ammine resulted in egg shell-type supported catalysts. The behavior was studied as a diffusion control of Pt complex ion in the pellet from the results of the relations between Pt penetration depth and soaking time. The catalyst from Pt (IV) ammine showed lower temperature performance than Pt (II) ammine in the catalytic combustion of methane.
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  • Shinichi Hasegawa, Keisuke Fukui, Syouji Hirota
    1997 Volume 23 Issue 2 Pages 194-199
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Liquid ice is useful as a cold thermal storage material. In our previous work, a heat transfer experiment in a 22 mm diameter vertical straight pipe was carried out, and the empirical correlation of capacity coefficient of heat transfer Ka [-] was obtained.
    In this work the effects of pipe diameter on Ka for straight-and coiled-pipe systems have been investigated. Experimental results showed that the coiled-pipe system was useful for continuous formation of liquid ice and enabled a compact device. For the straight-pipe system, Ka was proportional to the ratio of water and coolant mass flow rates. For the coiled-pipe system, on the other hand, Ka was independent of pipe diameter and was expressed only by an exponential function of the ratio of water and coolant mass flow rates.
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  • Satoshi Hirata, Masahito Taya, Setsuji Tone
    1997 Volume 23 Issue 2 Pages 200-207
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Chlorella sp. UK 001 cells were cultivated under a photoautotrophic condition, utilizing carbon dioxide and light as carbon and energy sources, respectively. In batch cultures of the cells for 96 h at incident light intensity (I0) of 21.8 W m-2, when the culture temperature (T) was kept at 40°C, mean diameter of the cells (dc) increased from 2.3 μm (standard deviation (SD) =0.36 μm) to 11 μm (SD = 1.9 μm), while at T = 20, 30, 35 and 45°C, the values of de hardly changed. Under the conditions examined, the appreciable enlargement of the cells occurred at T =40°C and at I0 = 16 to 46 W m-2, and was not accompanied by a substantial increase in the number of cells. From the data on cell viability, oxygen generation rate under light conditions and oxygen consumption rate under dark conditions, the enlarged cells in the culture at 40° C were found to have sufficient activities as living cells. Sedimentation experiments were carried out by standing the cells which were cultivated at 30 and 40°C. The interfacial sedimentation rate of the cells (dc= 11 μm, SD= 1.9 μm) obtained from the culture at 40°C was about twelve times higher than that of cells (de = 2.3 μm, SD = 0.38μm) at 30°C
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  • Takafumi Mikami, Hidehiro Kamiya, Masayuki Horio
    1997 Volume 23 Issue 2 Pages 208-215
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    A fluidized iron powder reduction process with controlled spontaneous agglomeration in a bed of inert material has been proposed. In this process agglomerates formed from fine iron powders in the region near the bed surface sediment through the inert bed whose height is adjusted so that a sufficient residence time is provided. The effects of the iron particle size, the fluidizing gas velocity and the bed height on the segregation/sedimentation behavior of iron particles in the fluidized bed were investigated. In a fluidized bed of 409 μm sand, iron powders of mean size of 36 and 78 μm segregated in the upper region of the bed as flotsam and iron agglomerates sedimented to the bottom of the bed. The operating ranges where the above concept can be established were found to be in a sufficiently wide range of bed height and gas velocity.
    In beds of SiC, Al2O3 and ZrO2 particles fluidized by the H2-N2 gas mixture, the possibility of agglomeration of a water-atomized iron powder and sedimentation of the agglomerates were confirmed experimentally. At relatively high temperatures agglomerates were irregular shaped and coarse, while at relatively low temperatures agglomerates were round and sparse.
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  • Yutaka Ohkubo, Yoshiki Takahashi
    1997 Volume 23 Issue 2 Pages 216-223
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Experimental and numerical approachs are taken to investigate the flux and concentration of powders lifted by induction-charge in a field with horizontally set parallel plate electrodes.
    The weight of the powders, lifted and attached to an adhesive on the upper electrode, is measured at certain time when a high voltage is supplied. The powder flux is obtained by taking the derivative of the coating weight of particles and gives a formula for the coating powder weight by integrating a curve which fits the data for the flux. It is found that the value for an initial flux of powder is composed of the density and diameter of the particle, calculated lifting cycle time, and proposed dimensionless flux number.
    The concentration of the lifted powders between electrodes is examined by using light to measure the density of the powder layer. The proposed theoretical formula for the concentration of powders is almost identical to the experimental results.
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  • Eiji Iritani, Sin-ya Akatsuka, Toshiro Murase
    1997 Volume 23 Issue 2 Pages 224-229
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The sedimentation rate in ultracentrifugation of an aqueous solution of the mixtures of bovine serum albumin (BSA) and egg white lysozyme has been measured using Schlieren optics in an analytical ultracentrifuge. It was highlighted through this study that the electrical nature of macromolecules plays a significant role in determining the sedimentation behavior in ultracentrifugation of binary protein mixtures. In the pH range where both protein molecules were electropositive, the molecules sedimented independently due to the electrostatic repulsive force acting between BSA and lysozyme molecules. In contrast, in the pH range where two protein molecules had opposite electrical charges, the complex was formed because of the electrostatic attraction between BSA and lysozyme molecules, and it sedimented with a sedimentation rate larger than that for free BSA alone. However, when enough salts were present in the solution, the electrostatic attraction between solutes was reduced due to repression of the electrical double layer, and thus a complex with a large sedimentation rate did not form. This study revealed that the solution environment can have profound effects upon the sedimentation behavior in ultracentrifugation of binary protein mixtures.
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  • Yoshinari Taguchi, Masato Tanaka
    1997 Volume 23 Issue 2 Pages 230-236
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Suspension polymerization of styrene was performed with a forward-reverse mixing method. In the experiments, four kinds of impellers were used and it was investigated how this mixing method affected the transient size distributions of polymer droplets and the size distributions of final polymer particles. The results were compared with those obtained by conventional mixing methods.
    The forward-reverse mixing method was found to prevent the polymer droplets from coalescing and to produce polymer particles of the smaller and more uniform sizes than the conventional mixing methods.
    Moreover, the forward-reverse mixing method was able to change the particle size dramatically.
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  • Kentaro Ohshima, Keiichi Tsuto, Kikuo Okuyama, Noboru Tohge
    1997 Volume 23 Issue 2 Pages 237-242
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    We have proposed composite fine particles, i.e. composite powders of ultra-fine particles, to show the optical function of ultra-fine particles by preventing them from aggregating. They have the structure where optically functional ultra-fine particles are dispersed and fixed in transparent inorganic fine particles. For instanse, spherical TiO 2/SiO2 composite fine particles with diameters from 0.48 to 0.59 im were prepared by the spray dry method from an aqueous solution of SiO2sol and TiO2 sol under various experimental conditions. It was confirmed by an electron microscope that the microstructure of prepared particles was composed of SiO2 fine particles with TiO2 ultra-fine particles being dispersed and fixed in them. Moreover, it was found that the particle diameter was increased at higher concentration of nebulized solution, and it was primarily concerned with the droplet diameter. The prepared particles showed the optical properties of TiO2 ultra-fine particles which had a high transparency in the visible range and a high shielding ability in the ultraviolet range. Accordingly, it is expected that prepared composite fine particles are applicable to cosmetics, paints, and other products as ultraviolet shielding agents with a high transparency.
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  • Takashi Sana, Kouji Nagayoshi, Koichiro Shiomori, Yoshinari Baba, Yosh ...
    1997 Volume 23 Issue 2 Pages 243-250
    Published: March 10, 1997
    Released: February 19, 2010
    JOURNALS FREE ACCESS
    The extraction equilibrium of acetic acid, malic acid, citric acid and lactic acid with tri-n-octylamine as extractant in toluene were measured at 303 K. Under this experimental condition, all fatty acids were not distributed in toluene.
    Organic acid, A, reacts with TOA, B, to form ion complexes in toluene. The formed complex species and equilibrium constants were estimated by graphical analysis. The complexes are AB (n=1-6) for acetic acid, (AB)n (n=1, 5) for malic acid, (AB) n (n=1, 6) for citric acid, and AnBm ((n≥m)n= 1, 2, 3, 4, 5/m=1, 2) for lactic acid, respectively. The experimental results could be explained by the proposed reaction models and the equilibrium constants were estimated.
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  • Osamu Miyatake, Kotaro Tagawa, Shuichi Takaki, Hidehiko Noda
    1997 Volume 23 Issue 2 Pages 251-258
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    As part of an attempt to develop a seawater RO desalination system utilizing the high static pressure of the deep-sea, a numerical analysis was performed to determine the axial variation of velocity, concentration and pressure in laminar natural convection flow, caused by the concentration difference in the moderately narrow annular passage formed between a tube type membrane and a cylindrical rod.
    A dimensionless equation was formulated from the numerical results to predict the transmitted fresh water flow rate from the width and the length of the passage, the submerged depth of the device, the permeability of membrane, and the physical properties of seawater. The transmitted fresh water flow rate exhibited an increase with decreasing width of passage up to a maximum at a width of about 1-2 mm, followed by a rapid decrease, and thus realized the existence of the optimum width of passage.
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  • Shiro Kiyoyama, Koichiro Shiomori, Yoshinari Baba, Yoshinobu Kawano, H ...
    1997 Volume 23 Issue 2 Pages 259-265
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Preparation of biodegradable microcapsules with poly (3 HB-co-3 HV) was performed by the (W/O/W) emulsion-solvent evaporation method. At first, (W/O) emulsion was prepared by dispersing an aqueous ascorbic acid magnesium salt solution into the organic solution consisting of poly (3 HB-co-3 HV), hexaglicerine ricynoreic acid and 1, 2-dichloroethane. Then, (W/O/W) emulsion was prepared by dispersing the (W/O) emulsion into the outer aqueous phase consisting of decaglicerinericynoreic mono lauric acid and polyvinylalcohol. Microcapsules with porous surfaces were formed by solvent evaporation. The characteristics of microcapsules were found to be controlled by operating conditions such as solvent evaporation rate, dispersion stabilizer and concentration of poly (3 HB-co-3 HV).
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  • Tetsuo Fuchino, Masaaki Muraki
    1997 Volume 23 Issue 2 Pages 266-271
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The maintenance cost should be considered in the early planning phase of process design for reducing it, and a cost estimation method is essential to evaluate alternative design. The shutdown maintenance of condition basis maintainable equipment modules is concerned here, then that maintenance plan through the plant life should be optimized on the basis of expected degradation curves of these equipment modules for an accurate process evaluation. The shutdown timing and grouping of equipment modules, which are maintained at each shutdown period, become decision variables, and these variables should be optimized simultaneously under the constraint of the degradation curves. In this study, the relation between these variables through the degradation curves is considered, and a sub-model for sequential two shutdown periods for any equipment module is provided by introducing 0/1 integer variables, and it is expanded for overall equipment modules and whole plant life. This model is linearized from the consideration of required accuracy in process evaluation, and an integer programming model for the shutdown maintenance planning is developed.
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  • Saburo Wakizaka, Isao Sekiguchi
    1997 Volume 23 Issue 2 Pages 272-279
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    This paper examines the close relationship which exist between asphalt temperature and surface tension in order to learn more about the surface chemistry of asphaltic materials and various kinds of aggregate materials. The relationship which is basically indicative of one of the most important properties of the asphalt can be established by measuring the contact angle of the asphalt meniscus formed in response to polyethylene.The well-known relationship between temperatures and surface tensions of α-bromonaphthalene has enabled the surface tension of polyethylene to be obtained by repeating the above procedure. Furthermore, it has been found that both the total surface energy and the surface entropy remain almost the same throughout the measurement. Surface tension and the surface entropy at a temperature of 293 K were found to be about 10-2N/m and about one order higher than the respective ones obtained by Saal. Asphalt specimens with a penetration of 60-80 are used in a thermal degradation test. Special attention is paid to what influence was time exerted on thermal degradation of the asphalt surface. It is concluded that the total surface energy and the surface entropy increase in all cases where thermal degradation is in progress.
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  • Masahiro Takahashi, Fumiyo Tani, Yuuko Kawai, Hiroshi Takeuchi
    1997 Volume 23 Issue 2 Pages 280-285
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The extraction equilibria of six kinds of amino acids with di (2-ethylhexyl) phosphoric acid (D 2 EHPA) dissolved in n-heptane were studied at 298.2 K in the low pH range (25). The distribution ratios of amino acid D+ as the cationic species were inversely proportional to the 1 st power of the concentration of hydrogen ion, and directly to the 0.5 th power of the concentration of D 2 EHPA. The extraction equilibrium constants Kex of the amino acids used were 0.650 (Phe), 0.420 (Trp), 0.320 (Leu), 0.275 (Met), 0.064 (Gly) and 0.040 (Ala) mol0.5·m-1.5. The highest Kex value was obtained for Phe, being larger than the value for Ala by a factor of about 16. It was found that the extraction equilibrium constants of amino acids increase with increasing hydrophobicity.
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  • Tadaaki Nishiki, Akinori Muto, Takeshi Kataoka
    1997 Volume 23 Issue 2 Pages 286-288
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The effects of several alcohol additions on backward extraction of lysozyme through the reverse micellar extraction were investigated. The reverse micellar phase was a 50 mol/m3 AOT/isooctane containing lysozyme in a concentration of 1 kg/m3 and the aqueous phase was a 1 kmol/m3 KCl solution at pH 11.5 containing the alcohol. There was little difference in the percent backward extraction with kind of alcohol, but the effect for accelerating backward extraction rate became large in the order of ethanol, isopropanol and 2-methyl-2-propanol.
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  • Kaoru Onuki, Hayato Nakajima, Saburo Shimizu
    1997 Volume 23 Issue 2 Pages 289-291
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The electrodialysis behavior of HIx solution (mixture of iodine and hydriodic acid) was examined using commercial ion exchange membranes, NEOSEPTA CMH and TOSFLEX IE-DF 34, from the viewpoint of concentrating HI. The concentration efficiency was found to be governed by ion selectivity and electric resistance of the anion exchange membrane, and also by water permeation through the cation exchange membrane due to osmosis and electroosmosis. The minimum current density required for the concentration was estimated using the measured electrodialysis rate of HI and the water permeation rate.
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  • Keiji Sakaki, Akira Endo, Toshio Osawa, Hiroshi Komiyama, Koichi Yamad ...
    1997 Volume 23 Issue 2 Pages 292-295
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    In this report, a solid oxide fuel cell (SOFC) system with fuel recycling was proposed, and its generation efficiency was evaluated. In the system, all of the fuel supplied is utilized for generation, and the open-circuit voltage is enhanced by the removal of CO2 and H2O from recycled fuel. Fuel recycling improves the generation efficiency of the SOFC system if the energy required for the separation of CO2 and H2O could be reduced to close to the separation free-energy.
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  • Tatsuo Kanki, Tsuyoshi Asano, Hiroshi Yamashita, Susumu Uetani, Hiroyo ...
    1997 Volume 23 Issue 2 Pages 296-299
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The interfacial tensions of two phase extraction systems, D 2 EHPA in benzene/ cupric aqueous solution and D 2 EHPA in benzene/ferric aqueous solution, were measured by a laser light scattering method. The interfacial tensions were confirmed to exhibit specific dependencies of extractant and hydrogen ion concentrations as had been determined by the Whilhelmy plate method. It was also verified that in the solution system without metallic ion, the monomer extractant and its anion are surface active, in a copper extraction system there forms no surface active intermediate complex, whereas in iron extraction system, there forms the 1 : 2 intermediate complex which is surface active.
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  • Manabu Yamaguchi, Masafumi Tachibana
    1997 Volume 23 Issue 2 Pages 300-302
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Deformation and disintegration behavior for single water drops falling through a silicone oil phase in a DC electric field were studied experimentally. The experimental maximum deformation degree of the drops just before their disintegration agreed approximately with the theoretical value proposed by Taylor, but the experimental critical field strength for drop disintegration was lower about 26% than his theoretical one. Two types of electrical disintegration for falling drops were observed depending on the size of the drops : a small deformed drop was disintegrated by ejecting a series of smaller drops at its sharp pointed ends, while a large drop was elongated as a rod-like shape and immediately disintegrated into several small drops.
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  • Kazuya Ijichi, Yasuo Hatate, Shiro Kiyoyama, Koichiro Shiomori, Yoshin ...
    1997 Volume 23 Issue 2 Pages 303-306
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Cross-linked polystyrene microcapsules with numerous uniform spherical pores were prepared by in situ polymerization of styrene-divinylbenzene in a (W/O/W) emulsion system. At first, the (W/O) emulsion was prepared by dispersing an aqueous inorganic salt solution into the organic solution consisting of styrene monomer, divinyl -benzene, ADVN, hexaglicerine ricynoreic acid and toluene. Then, (W/O/W) emulsion was prepared by dispersing the (W/O) emulsion into the outer aqueous solution containing sodium dodecylbenzene-sulfonic acid and polyvinylalcohol.
    Microcapsules having porous spaces in the sphere and on the surface were formed by in situ polymerization. The characteristics of microcapsules were found to be controlled by the operating conditions as salt in inner aqueous solution, the ratio of styrene and ADVN, concentration of styrene and surfactant in oil phase and fraction of inner aqueous solution.
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  • Ryuichi Moriyama
    1997 Volume 23 Issue 2 Pages 307-310
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    It is already known that although a coarse bed achieved by central feeding flows down with a perfect mass flow during discharge, that of a dense bed achieved by peripheral feeding brings about a pulsating wall pressure at the hopper gate in a bin.
    This paper outlines the wall pressure generated during the discharge of a bed achieved by combinational filling methods, such as a coarse bed piled up above a dense bed or the opposite.
    As a result, it was found out that the severe pulsating wall pressure occured at the hopper gate, in the case of a combination bed achieved by central feeding on the surface after filling from the hopper gate to the initial upper parts of the cylindrical section by peripheral feeding.
    The mechanism was explained by reasoning that arching occuring at the hopper gate grows strong under flowing conditions such as becoming vertical load to flow joins above a dense filling bed unbecoming to a flow.
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  • Issei Fujiyoshi
    1997 Volume 23 Issue 2 Pages 311-314
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The adsorption experiment of ethylenediaminecobalt complex ion on porous glass showed selective adsorption of monoethylenediaminecobalt complex ion obeying the mass action law, which yielded the apparent asdsorption equilibrium constant of 4.11× 10-14 kg·mol·m-6 and the effective amount of adsorptive site on porous glass of 3.74 mol·kg-1 at 298 K. But the mass action law described above did not applied for molarity ratio of over three of ethylenediamine to cobalt, because of change of composition by oxidation of cobalt complex ion and the desorpting effect by free ethylenediamine.
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  • Hironori Kitazaki, Masayuki Ishimaru, Katsutoshi Inoue, Shuji Nakamura
    1997 Volume 23 Issue 2 Pages 315-318
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    In previous works, it was elucidated that baicalein and baicalin belonging to flavonoids can be mutually separated by solvent extraction with trialkylphosphine oxides. In this work, in order to obtain the basic information of separation of various kinds of flavonoids, i.e., flavone, flavonol, 7, 8-dihydroxyflavone, baicalein and baicalin, their aqueous solubilities and the extraction behavior with various kinds of extractants in hexane were examined.
    From these results, a separation process of flavonoids is proposed in the case that baicalin is a target substance.
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  • Toshiyuki Maeda, Masaaki Yoshikawa, Mitsuaki Yamada, Hiroaki Matsuyosh ...
    1997 Volume 23 Issue 2 Pages 319-323
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Pitch fluoride is a new fluorine carbon compound which has superior water repellency with a contact angle of more than 145 degrees. In this study, adopting solid pitch fluoride as a starting material, liquid and solid glassy types of pitch fluoride were synthesized by direct fluorination at final temperatures ranging from 200°C to 400°C. The reaction conditions giving the maximum yield of liquid fluoride were investigated. Synthesized liquid pitch fluoride was distilled under a reduced pressure and fractionated at different temperatures. Measurements of average molecular weight and 19F-NMR and elementary analysis were conducted for the fractionated liquid fluoride as well as the synthesized liquid and glassy products, together with the measurements of surface tension, viscosity, refractive index and specific gravity.
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  • Kenji Nakano, Masahiko Shimoda, Yoshimitsu Uemura, Yasuo Hatate
    1997 Volume 23 Issue 2 Pages 324-326
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    A batch-rectification experiment to remove a minute amount of furfural from ethanol aqueous solution was carried out by use of an Oldershow-type column consisting of ten plates. At first, the experiment was carried out under total reflux conditions. Furfural was concentrated on the seventh plate from the top, and side-cut was carried out at this plate. The plate efficiencies of ethanol and furfulal were obtained from the total reflux condition data. A mathematical model was constructed and distillation curves of ethanol and furfural were calculated. It was shown that the calculated curves of ethanol and furfural agreed with the observed ones.
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  • Toyozo Hamada, Masahito Taya, Setsuji Tone
    1997 Volume 23 Issue 2 Pages 327-330
    Published: March 10, 1997
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    The permeation fluxes for mixtures of water-ethanol at 343 K and water-2-propanol at 356 K were determined in pervaporation and vapor permeation experiments using a polyion complex membrane. The total permeation fluxes and separation factors were calculated by applying solution-diffusion theory to the data in both experiments, and separation indexes were obtained as the product of the calculated values of total permeation fluxes and separation factors. The separation indexes for water-ethanol and water-2-propanol mixtures in the pervaporation were higher than those in the vapor permeation at mole fraction of ethanol in feed solution above 0.82 and at that of 2-propanol above 0.43, respectively.
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  • 1997 Volume 23 Issue 2 Pages e1a
    Published: 1997
    Released: November 12, 2009
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  • 1997 Volume 23 Issue 2 Pages e1b
    Published: 1997
    Released: November 12, 2009
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  • 1997 Volume 23 Issue 2 Pages e1c
    Published: 1997
    Released: November 12, 2009
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  • 1997 Volume 23 Issue 2 Pages e1d
    Published: 1997
    Released: November 22, 2010
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