KAGAKU KOGAKU RONBUNSHU
Online ISSN : 1349-9203
Print ISSN : 0386-216X
ISSN-L : 0386-216X
Volume 27 , Issue 2
Showing 1-27 articles out of 27 articles from the selected issue
Special Issue [Bioseparation Engineering]
  • Masami Shiozawa, Hironao Okabe, Yasuhiro Nakagawa, Hiroshi Morita, Tos ...
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 145-148
    Published: March 20, 2001
    Released: December 30, 2008
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    Lactoferrin, which binds iron very tightly but reversibly and is a useful protein because of its various biological functions, was purified from defatted milk by use of an expanded-bed column with Streamline SP as adsorbent. Adsorption of lactoferrin in defatted milk is found to obey a Langmuir isotherm. The isotherm is also obeyed in phosphate buffer, and the amount of lactoferrin adsorbed decreased rapidly with an increase of NaCl in the buffer. With the expanded-bed column nearly 90% of lactoferrin in the applied milk is recovered with purity of ca. 90% through high apparent velocity of ca. 150 cm/h in the bed.
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  • Shigeo Katoh, Masukazu Okuda, Masaaki Terashima
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 149-152
    Published: March 20, 2001
    Released: December 30, 2008
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    A characterization method for a C-terminal region of recombinant protein is studied. Recombinant protein was specifically digested by protease to peptide fragments, and then the target C-terminal peptide was purified with affinity chromatography by anti-peptide antibody column from the peptide fragments and analyzed by HPLC. From the retention time and the peak height, the correctness and amount of the C-terminal peptide were determined. With combining the N-terminal sequence method, the soundness and amount of recombinant proteins can easily be determined.
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  • Hidefumi Yoshii, Junji Shimizu, Yuuki Kugimoto, [in Japanese], Takeshi ...
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 153-158
    Published: March 20, 2001
    Released: December 30, 2008
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    Contamination of soil by PCB and dioxin is a serious pollution problem. The compounds have high affinity with soil, so that effective removal of the compounds from the soil is an important technical problem. The aim of this study is the development of the removal process of the contaminated compounds from soil by including the compound selectively in the cavity of cyclodextrin. In this work, to obtain fundamental knowledge for the remediation of soil by means of cyclodextrin, biphenyl was used as a model contaminated compound. We carried out fundamental studies such as enhancement of the solubility of biphenyl by cyclodextrin, the desorption of biphenyl from the soil by kneading the mixture of the contaminated soil and cyclodextrins using a twin-screw kneader, and biodegradation of the biphenyl included in an aerobic system by activated sludge. Among various cyclodextrins, hydroxypropyl-β-cyclodextrin (HP-β-CD) shows the highest enhancement of the solubility of biphenyl. Desorption of biphenyl from the contaminated soil is the most effective in the case of using HP-β-CD by means of a twin-screw kneader.
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  • Masaru Hakoda, Yoshikazu Wakizaka, Naohiro Shiragami
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 159-164
    Published: March 20, 2001
    Released: December 30, 2008
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    We apply dielectrophoresis to separation of cells in a culture broth by considering the difference of dielectric constant between alive and dead cells. In this paper, the dependency of the applied a-c voltage' s frequency on the dielectrophoresis for yeast, E-coli, animal cells is studied and the method of cell collection is also discussed.
    A suspension of cells was filled into well mounted pin-plate electrodes and well mounted wire-cylinder electrodes, and an a-c voltage was applied between the electrodes. The ranges of the electric field strength and the frequency were from 2 x 103 V/m to 1 x 105 V/m and from 1 kHz to 1 MHz, respectively.
    Three kinds of alive cells can be collected at a frequency of 1 MHz, and the dead cells can never be collected at this frequency. At that time, there was no detrimental effect, even when applying the a-c electric field of 1 x 103 V/m to alive cells. The collection rate of alive cells is greatly influenced by the electric conductivity of the culture broth. The optimum electric conductivity for the collection rate of alive cells is 100 µS/cm.
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  • Shinji Sakai, Tsutomu Ono, Hiroyuki Ijima, Koei Kawakami
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 165-168
    Published: March 20, 2001
    Released: December 30, 2008
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    In order to develop a microcapsule-shaped bioartificial pancreas, it is important to control the transport characteristics of the semipermeable membrane. We attempt to control the transport characteristics of the membrane by changing the coating layer number of polyelectrolyte complex between glycol chitosan (GC, M. W. > 8.2 X 104) and alginate (Alg) on the microcapsule. From measurement of diffusivities of bovine serum albumin (BSA, M.W. = 6.7 x 104) and γ-globulin (M.W. = 1.6 x 10'), these diffusion rates through the membrane drastically decrease with increasing layer number of GC-Alg. The microcapsule coated with four layers of polyelectrolyte complex successfully rejects γ-globulin with effective permeability of BSA. In addition, the diffusivity of glucose (M.W. = 180) indicateds that the multi-layering of polyelectrolyte complex hardly affects the diffusivity of small substances such as nutrients and oxygen. These results indicate that the polyelectrolyte complex prepared by the multi-layering method is useful to control the transport characteristic of membranes and the four-layered GC -Alg polyelectrolyte complex microcapsule is promising for a microcapsule-shaped bioartificial pancreas.
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  • Daisuke Nohara, Daisuke Kondoh, Tomoya Sakai
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 169-173
    Published: March 20, 2001
    Released: December 30, 2008
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    In order to suppress autolysis which decreases recovered activity, synthesized inhibitor is applied to protease refolding. In the refolding of Streptomyces griseus trypsin (SGT) from its denatured and reduced state, recovered activity reaches only 15% by the ordinary dilution method, while it exceeds 60% in the presence of the gel on which p-aminobenzamidine, an inhibitor to trypsin, is immobilized covalently. Furthermore, by use of the immobilized inhibitor, purification and recovery of renatured SGT are efficiently performed. In addition, aggregation, the other disadvantageous reaction to renaturation, can also be diminished with coexistence of 1 M urea in this suspension system. Reusability of the immobilized inhibitor will make it possible to develop this refolding into the continuous process.
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  • Seong Hoon Kim, Ritsuko Otani, Wataru Shirai, Naomi Shibasaki-Kitakawa ...
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 174-180
    Published: March 20, 2001
    Released: December 30, 2008
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    An unsteady state mathematical model describing the continuous separation process of a binary mixture of protein using partial recycling free-flow isoelectric focusing is constructed. The model consists of a one-dimensional mass balance equation and an electric charge balance equation for the electrophoretic chamber and a mass balance equation for the reservoir. The model equations were solved numerically using a finite difference method with literature values of physical constants such as dissociation and diffusion constants. The calculated results are in good agreement with the experimental data for the separation of protein mixture of bovine serum albumin (BSA) and bovine hemoglobin (Hb) reported previously. Furthermore, the model can describe the effects of the operating factors, such as support electrolyte concentration and feed flow rate, on the separation process.
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  • Masahiro Goto, Maki Korenaga, Tsutomu Ono, Shintaro Furusaki
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 181-185
    Published: March 20, 2001
    Released: December 30, 2008
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    Extraction behavior of active and denatured a-chymotrypsin is investigated by the reversed micellar extraction technique. The anionic surfactant dioleyl phosphoric acid (DOLPA) selectively extracted the active protein over the denatured protein. However, the reversed micelles using AOT do not afford selectivity. Based on the difference in the structural properties between the active and the heated a-chymotrypsin, the extraction behavior by the DOLPA reversed micelles is discussed.
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  • Takashi Ishihara, Shuichi Yamamoto
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 186-190
    Published: March 20, 2001
    Released: December 30, 2008
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    Molecular recognition in hydroxyapatite chromatography (HAG) and ion exchange chromatography (IEC) is investigated. A fast and simple method for obtaining important information on the number of binding sites from linear gradient elution experiments (salt concentration is increased linearly at a fixed mobile phase pH) is first described. Linear gradient elution experiments for HAC and IEC were carried out with β-lactoglobulin (Lg) and Ribonuclease A (RNaseA) as model proteins. The experimental data were analyzed on the basis of the above-mentioned method.
    The peak salt concentration IR and the number of binding sites B in IEC decrease as the mobile phase pH approaches the isoelectric points pl (Lg=5.1-5.3, RNaseA=9.7) for both Lg and RNaseA. The IR and B values of Lg in HAC decrease as the mobile phase pH increases. Although the IR values of RNaseA in HAC decrease with an increase in the mobile phase pH, the B values are constant (B ca. 5) and did not depend on the mobile phase pH. Two genetic variant forms of Lg, β-lactoglobulin A and β-lactoglobulin B, are not separated on HAC and cation-exchange chromatography. The two proteins are separated only on anion-exchange chromatography. On the basis of these experimental findings the molecular recognition mechanism of HAC with Lg and RNaseA is discussed in comparison with the mechanism in IEC.
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  • Satoshi Yamaguchi, Teruhisa Mannen, Tamotsu Zako, Teruyuki Nagamune
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 191-196
    Published: March 20, 2001
    Released: December 30, 2008
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    The structural information of protein molecules on solid phase, such as conformation and orientation, has attracted much attention. In this report, we try to evaluate structural change of proteins via measurement of the adsorption amount of non-ionic detergent (TritonX-100) to proteins immobilized covalently on the matrix surface by a surface plasmon resonance (SPR) sensor. The adsorption amount of detergent to α-glucosidase and apomyoglobin is dependent on the amount of immobilized proteins and their surface net hydrophobicity. Moreover, it is observed that the adsorption amount of detergent to proteins increases in proportion to the denaturation degree of proteins induced by 6 M guanidinium chloride solution. Consequently, it is revealed that measurement of the adsorption amount of detergent to proteins is applicable to detecting conformational changes of proteins on solid phase.
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  • Hiroshi Umakoshi, Ryoichi Kuboi, Folke Tjerneld
    Type: Fundamental Research Paper
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 197-204
    Published: March 20, 2001
    Released: December 30, 2008
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    The partition coefficient of proteins (carbonic anhydrase from bovine (CAB) and lysozyme treated under reducing conditions) was quantitatively evaluated in Breox/dextran aqueous two-phase systems in order to develop a stress-mediated bioseparation process using the conformational change of proteins and the stimuli-responsive aqueous two-phase systems. A comparison of the partition coefficients with the surface properties, previously characterized, shows that the change of protein conformation and their surface properties (i.e. surface net and local hydrophobicity) can be estimated simply by using the partition coefficient and without analyzing of the properties of the partitioning systems. The values of both the stimuli (temperature and GuHCI concentration) and the conformational change, estimated from the partition coefficients, were normalized. As a result, the combined stimuli of temperature and GuHCI concentration to determine the protein conformation were found to be expressed as a linear summation of them. The methodology for the design of the separation process was investigated based on the diagram for GuHCI concentration and temperature, in which the local hydrophobicity was maximal, and the separation of lysozyme and CAB was achieved as a model case of the methodology.
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  • Eiji Miyagawa, Shuichi Yamamoto
    Type: Note
    Subject area: Bioseparation Engineering
    2001 Volume 27 Issue 2 Pages 205-207
    Published: March 20, 2001
    Released: December 30, 2008
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    A monoclonal antibody (mAb), gp 21-34 which specifically recognizes Human T-cell lymphotropic virus type-II (HTLV-II) transmembrane envelope glycoprotein (p 20 Ell) was coupled to Sepharose gel. A column packed with this gel specifically adsorbed p 20 E II and then desorbed with 3 M potassium thiocyanate. However, different virus type proteins HTLV-I p 20 E I are not adsorbed to the column. The mAb gp 21-34 coupled Sepharose column is useful for selective purification of p 20 E II and selective concentration of HTLV-II virions.
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Transport Phenomena, Fluid Mechanics and Mixing
  • Nobuo Matsuda, Yutaka Tada, Setsuro Hiraoka, Yukihiko Mouri, Young-sei ...
    Type: Fundamental Research Paper
    Subject area: Transport Phenomena, Fluid Mechanics and Mixing
    2001 Volume 27 Issue 2 Pages 259-264
    Published: March 20, 2001
    Released: December 30, 2008
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    The velocity in an agitated vessel with three kinds of impeller (paddle, pitched blade paddle, and Rushton turbine) was measured with two-dimensional laser-doppler velocimetry (LDV) and the flow was visualized in order to investigate the relation between the low frequency fluctuation in the velocity and the flow in the vessel. The velocity time series obtained was analyzed with statistical stochastics and with the power spectrum. There is a significant velocity fluctuation in the lower frequency region, the frequency of which, f,,, corresponds to 20-30 times the blade passage frequency and is proportional to the rotational speed in the range 0.667-2.00 s-1. The proportional coefficients between the frequency and the rotational speed are specific to the impellers and depend on the type, the number of blades, and the set -up position of the impellers. There are significant velocity fluctuations in the very low frequency region, the frequencies of which, fL and fs, correspond to 100-300 times the blade passage frequency and are proportional to the rotational speed. The proportional coefficients depend on the type and the number of blades, and depend slightly on the set-up position of the impellers. It is found from the flow visualization that the frequency of the fluctuation, f,,, corresponds to that of the flow which crosses the impeller shaft, and the low frequency fluctuation in the flow corresponds to that of the change in the large-scale flow pattern caused from the blade passage.
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  • Toshikatsu Tsuyuki, Yoshihiro Iida, Kunito Okuyama
    Type: Note
    Subject area: Transport Phenomena, Fluid Mechanics and Mixing
    2001 Volume 27 Issue 2 Pages 275-277
    Published: March 20, 2001
    Released: December 30, 2008
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    A non-dimensional equation is proposed to correlate the nucleate boiling heat transfer data from a horizontal cylinder to a liquid containing movable solid particles. The non-dimensional numbers which will be available for the correlation are discussed, and the correlation equation is derived through the regression analysis of experimental data. Particle materials used were alumina and glass, and diameter ranged from 0.3 to 2.0 mm, while the thickness of the particle bed varied from 5 to 80 mm. The heat flux was varied from 6.5 x 10' to 9.1 x 10' W/m2 and the superheat from 2.1 to 27 K.
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  • Takeshi Yamane, Masamichi Yoshida, Hisashi Miyashita
    Type: Note
    Subject area: Transport Phenomena, Fluid Mechanics and Mixing
    2001 Volume 27 Issue 2 Pages 278-281
    Published: March 20, 2001
    Released: December 30, 2008
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    He-Ne laser holographic interferometry is applied to double-diffusive convection in Na2CO3 aqueous solutions stratified in two layers when destabilized by lateral heating and cooling. Based on knowledge cultivated in the past, a summary of the density field is conjectured by the temporal changes of interference fringes. Because thermal and solutal gradients coexist, reflective index contours do not correspond to density contours. However, it is found that interference fringes in this system can be considered as density contours except for the circumference of the layers. Variations of density distribution going with interfacial mass transfer are explained in detail.
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Materials and Devices
Process System Engineering
  • Chie Sato, Tetsuya Ohtani, Hirokazu Nishitani
    Type: Fundamental Research Paper
    Subject area: Process System Engineering
    2001 Volume 27 Issue 2 Pages 265-271
    Published: March 20, 2001
    Released: December 30, 2008
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    In an industrial gas-phase polymerization process, process dynamics change considerably due to grade and load changes, and these changes present a difficult control problem. In this paper, a nonlinear physical model is effectively used for control system design. First, we developed a set of physical models of an industrial ethylene polymerization process, referring to McAuley's model. Parameters in the model were adjusted in order to simulate the actual process behavior. We examine the changes of process dynamics under typical operating points for different grade products. Second, in the control system design, the process is regarded as a two-input and two-output system. The two inputs are the feed rates of fresh hydrogen and butene, and the two outputs are cumulative melt index and density. An optimal servo controller with integral actions is designed according to the optimal regulator theory using a model linearized at a nominal operating point of the target grade. As a result, the optimal servo controller with integral actions results in better control performances during critical grade changes than the PID controller does.
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  • Yoshitomo Hanakuma, Junzou Yamamoto
    Type: Note
    Subject area: Process System Engineering
    2001 Volume 27 Issue 2 Pages 272-274
    Published: March 20, 2001
    Released: December 30, 2008
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    Methods of forecasting on time series data by auto-regressive model, neural networks model and chaotic theorem are proposed. The methods are said to be complicated for forecasting calculations. In this paper, a simple forecasting algorithm by the nearest neighbor method is discussed. It is applied to forecasting on a monthly average temperature in Sendai city to confirm performance. The actual results indicate that the nearest neighbor method has similar performance to the auto-regressive model in forecasting on time-series data.
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Biochemical, Food and Medical
  • Shinichi Ookawara, Akihisa Yano, Kohei Ogawa, Koichi Taniguchi
    Type: Technical Research Paper
    Subject area: Biochemical, Food and Medical
    2001 Volume 27 Issue 2 Pages 228-235
    Published: March 20, 2001
    Released: December 30, 2008
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    Estimation of red cell deformability and plasma viscosity by a neural network is examined for clinical application, which is based on a flow curve in the high shear rate range of 1,000-10,000 s-1 obtained by a blood viscometer presently employed in a hospital. Newly defined indices DI,5 and D14o as quantified deformability were proposed in this study, which reflect the elongation of red cells under shear stress of 15 Pa and 40 Pa, respectively. It is found that a combination of non-Newtonian model parameter values gives a unique set of those quantified deformability indices and plasma viscosity under the assumption that the volume fraction of red cells (Hct) is known. A feed forward neural network newly constructed in this study, has inputs of Hct, Bingham viscosity, yield stress, exponent of power law model and outputs of those deformability indices and plasma viscosity. Though practical accuracy was not attained for the estimation of plasma viscosity, it is expected that clinical application of this method is possible for the estimation of D115 and D140.
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Safty, Enviroment and Energy
  • Daisuke Hirabayashi, Liwei Huang, Hitoki Matsuda, Naoki Tanahashi
    Type: Technical Research Paper
    Subject area: Safty, Enviroment and Energy
    2001 Volume 27 Issue 2 Pages 208-216
    Published: March 20, 2001
    Released: December 30, 2008
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    The applicability of Ca-compounds involved in coal burnt ashes to dry gas sorbent for HCl removal is experimentally studied. The experiments for HCl sorption are conducted by employing different kinds of coal burnt ash discharged from a fluidized bed coal combustor (FBC), circulating fluidized bed coal combustor (CFBC), and pulverized coal combustor (PCC). The experiments were carried out with a packed bed of coal burnt ash 44-63 μm in mean diameter, through which the HCI gas of initial concentration of 1,000 ppm was made to flow under atmospheric condition in the temperatures range of 473 to 1,073 K.
    Experimental results show that the HC1 conversion of coal burnt ash increase with the increment of the amount of Ca-compounds contained in the ash. There is an optimum temperature range between 673 and 873 K for HCl sorption for the employed ash samples. It is found that a part of Ca component did not show any reactivity for HC1 sorption. Such Ca compornents, were considered to be in the form of melted amorphous silicate, oxide and sulfate, in accordance with the element distribution analysis on the surface of ashes by SEM/EDX.
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  • Shuichi Aoki, Yasutaka Kume
    Type: Technical Research Paper
    Subject area: Safty, Enviroment and Energy
    2001 Volume 27 Issue 2 Pages 217-222
    Published: March 20, 2001
    Released: December 30, 2008
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    To estimate the noise emitted by a radiant tube burner, simulated and experimental analyses are carried out. Firstly, combustion noise is measured and the overall characteristic of noise is examined. Secondly, one-dimensional noise analysis programmed with a transfer matrix methodis used. In the previous study, an industrial combustion device with a relatively simple designwas used, and the mechanisms of the emitted noise were clarified. However, at the resonance frequency, the magnitude of the calculated noise was not in agreement with the experiment. Thus, in this study, the decrement of noise energy in addition to the heat generation ratio distribution was taken into account to obtain sufficient accuracy of the noise at the exhaust tube outlet.
    As a result, the theoretical results in the cases of changing heat input and atmospheric temperature show relatively good agreement with the experimental results, and the analytical method employed in this study has been confirmed to be practical for noise analysis in radiant tube burners.
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  • Akitoshi Seya, Ichiro Tadano
    Type: Technical Research Paper
    Subject area: Safty, Enviroment and Energy
    2001 Volume 27 Issue 2 Pages 223-227
    Published: March 20, 2001
    Released: December 30, 2008
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    Phosphoric Acid Fuel Cells have excess electrolyte in each cell to compensate for acid loss during operation. We studied the distribution of excess electrolyte among the cell components during operation. For that purpose, we used small single cells to disassemble those cells immediately after operation. As a result of experiments, it is found that excess electrolyte almost exists in carbon components of the anode during operation. We suppose this is caused by migration of phosphoric acid ions from cathode to anode as a certain portion of the ion current during operation. This excess electrolyte movement to the anode does not have a bad effect upon the functions of each catalyst layer and matrix. But it is very important to consider this distribution of excess electrolyte to anode to design the amount of excess electrolyte and the capillary forces of cell the components.
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  • Michitaka Furubayashi, Rikio Shinohara, Kenichi Nagai
    Type: Fundamental Research Paper
    Subject area: Safty, Enviroment and Energy
    2001 Volume 27 Issue 2 Pages 236-242
    Published: March 20, 2001
    Released: December 30, 2008
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    Dioxin removal by activated carbon is studied by using a fixed bed type column and 1,2,3,4-tetrachlorinated dibenzo-p-dioxin (T4CDD). Effects of running time, T4CDD concentration of inlet gas, amount of activated carbon used, valid particle diameter of activated carbon, gas temperature, and superficial gas velocity in the column on T4CDD removal were analyzed and cleared. The effects were explained by the model that T4CDD removal is controlled by mass transfer rate in a boundary film on activated carbon particles and in the pores of them. T4CDD removal is little affected by the existence of 1,2,3-trichlorobenzen and sulfur dioxide in the gas phase, and is enhanced by the existence of hydrochloride in the gas phase.
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  • Morihisa Yokota, Tatsuo Nishimura, Yuutaro Kawasaki, Masami Hayashi
    Type: Fundamental Research Paper
    Subject area: Safty, Enviroment and Energy
    2001 Volume 27 Issue 2 Pages 243-250
    Published: March 20, 2001
    Released: December 30, 2008
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    A novel experimental procedure is presented to evaluate changes in particle diameter and density during combustion under reaction-controlled conditions. Three samples with a mean diameter of 90 um are employed, i.e., petroleum coke, graphite and gasifier residue. We carried out both thermogravimetry and particle imaging techniques under the same thermal conditions for each sample. It is revealed that petroleum coke particles shrink with a constant density, while the particle diameter and density simultaneously decrease for the others. In addition, the kinetics of the reaction order of petroleum coke with oxygen was determined in the temperature range 700-900 K. Reaction order in 02 of 1.0 and activation energy of 157 kJ/mol are obtained. Combustion kinetics of graphite and gasifier residue are also discussed briefly.
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  • Koichi Hirose, Nobutaka Kitazawa, Takao Yokoyama
    Type: Fundamental Research Paper
    Subject area: Safty, Enviroment and Energy
    2001 Volume 27 Issue 2 Pages 251-258
    Published: March 20, 2001
    Released: December 30, 2008
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    The characteristics of ice melting heat transfer in a horizontal elliptical tube immersed in water are studied experimentally and numerically. This phenomenon is caused by a combination of the natural convection heat transfer of water around the tube and ice melting heat transfer inside the tube. This combined heat transfer process has been studied numerically. A large number of studies on melting heat transfer in a simple shape capsule has been done; however, study of melting heat transfer in a horizontal elliptical tube are few. Ice melting characteristics, temperature profiles, flow patterns, average Nusselt number profiles, and ice melting rate are shown.
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  • Mitsuhiro Kubota, Kuniaki Yokoyama, Fujio Watanabe, Noriyuki Kobayashi ...
    Type: Note
    Subject area: Safty, Enviroment and Energy
    2001 Volume 27 Issue 2 Pages 285-287
    Published: March 20, 2001
    Released: December 30, 2008
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    The heat release and recovery characteristics of a CaO/CaCO3 type high temperature chemical heat pump were investigated experimentally by using a packed bed reactor with a single pipe heat exchanger.
    It is verified that carbonation of CaO has the ability to upgrade the temperature of the bed, and the generated heat energy can be recovered by air. The upgraded temperature can be controlled by adjusting the pressure of CO2. The amount of heat recovered (Q) increases with increases in air flow rate and C02 pressure. There is an optimum value of particle size for Q.
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