All issues
Volume 31, Issue 9
Displaying 1-10 of 10 articles from this issue
- |<
- <
- 1
- >
- >|
-
Yoshinobu FUKUMORI1994 Volume 31 Issue 9 Pages 619
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (1924K) -
Takashi OGIHARA, Masaki YABUUCHI, Teruaki YANAGAWA, Nobuo OGATA, Kouki ...1994 Volume 31 Issue 9 Pages 620-625
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSAn apparatus for continuous production of monodispersed, spherical ferric oxide particles was designed. The apparatus consisted of two starting solution reservoirs, a feeder, a mixer and a teflon reaction vessel. Monodispersed, spherical ferric oxide particles were prepared from the hydrolysis of Fe(OC4H9)3 in the octanol/acetonitrile solution. The influences of experimental factors such as reactant concentration, reaction time and temperature, flow rate and type of mixer on the formation of monodispersed particle were investigated. Monodispersed ferric oxide particles can be produced reproducibly by this technique.View full abstractDownload PDF (3461K) -
Naoya KOTAKE, Hitomi SHOJI, Masahiro HASEGAWA, Yoshiteru KANDA1994 Volume 31 Issue 9 Pages 626-630
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe demand for fine particles is increasing in many industries, thus, it is important to evaluate the fine grindability of solid materials. The Work Index proposed by Bond is an important factor in designing a grinding process and has been widely used.
In this paper, the authors proposed a corresponding Work Index Wi, c. which is proportional to the Work Index. Wi, c could be estimated by the examination of the zero-order increasing rate constant of the mass fraction less than a sieving size. Ball mill grinding was carried out on silica glass to measure the rate constant. The mill used was made of alumina with a diameter of 144mm and an inner length of 130mm. Its volume was about 2.1 liters. The grinding balls were also alumina with a diameter of 20mm. The relationship between Wi, c and the sieving size was studied.
As the results, it was presumed that the Work Index could be approximately constant to a sieving size of 20μm and increased in the range of a size less than 20μm.View full abstractDownload PDF (536K) -
Eiki ADACHI, Hideyuki YOSHIMURA, Kuniaki NAGAYAMA1994 Volume 31 Issue 9 Pages 631-634
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSAn imaging method for real-time visualization of a dynamic surface phenomena was developed based on a null ellipsometry with a white light source. Its performance was demonstrated by monitoring the process of a protein monolayer formation on a gallium surface. This method is significant because it visualizes the thicknesses and refractive indices of films on any types of substrate surfaces.View full abstractDownload PDF (1525K) -
Tatsuya UEDA, Hiroshi KITAMURA, Shinichi OMOTE, Hiroshi KITAWAKI, Masa ...1994 Volume 31 Issue 9 Pages 635-639
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSBy investigaing the microstructure of two types of pottery stones with different rheological properties by three methods, it was possible to determine the actual differences in particle aggregation. Furthermore, by altering slurry pH through the addition of nitric acid and ammonia solutions, it was possible to estimate particle aggregation and such relative factors as acidity, neutrality and alkalinity on the basis of variable apparent viscosity, ζ-potential, adsorption and dissolution.View full abstractDownload PDF (2072K) -
Measurement of Apparent AdhesionMasanori TAKATA, Tomoaki FUKUDA1994 Volume 31 Issue 9 Pages 640-646
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSIn order to predict the weight loss of a powder on the dividing and packaging machine, adhesion of Lactose G® and Crystalline Lactose with sieving particle diameters of 32/50, 50/100, 100/200 and 200 mesh pass were investigated. The examination of the apparent adhesion to the polyethylene laminate glassine paper and to four types of materials (processed glass beads shot, teflon, ground and crude stainless steel 304) used in the dividing and packaging machine showed a larger adhesive in the smaller size of both lactoses. There were significant correlations between the apparent adhesion and weight loss to the glassine paper and to the ground stainless steel 304 in each of the lactoses. No correlation was seen between the adhesive force of polyethylene laminate glassine paper obtained from the shear test and wall friction test on weight loss.
It is concluded that the measurement of apparent the adhesion of powder is suitable for the anticipation of weight loss.View full abstractDownload PDF (2283K) -
The Effect of Nitrate on GrindabilityFumikazu IKAZAKI, Kunio UCHIDA, Kunio KAMIYA, Akiko KAWAI, Satoshi YOD ...1994 Volume 31 Issue 9 Pages 647-651
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSChemically assisted comminution, in which chemical and/or physicochemical actions are introduced into powders to be ground, was conducted under dry conditions. The comminution method is called “chemically assisted dry comminution” (CADC). In the CADC sericite powder, a kind of mica, was first mixed with a nitrate, and the mixed powder was comminuted under a dry condition, followed by obtaining finely ground sericite after removing the nitrate by water cleaning. Lithium, sodium, potassium and rubdium nitrate were used as the nitrates.
The sericite powder obtained by every CADC had a much larger specific surface area and a smaller amount of impurity than that obtained by an ordinary dry comminution. On the other hand, the median diameters of sericite by CADC were slightly smaller than those by an ordinary dry comminution.
Potassium ions in sericite decreased only in the case of the CADC, which suggested that potassium ions were exchanged with alkali ions in the nitrate during the CADC. There was a correlation between the amount of exchanged potassium ions and the specific surface area of the sericite by the CADC. Stabilisation of the nascent surface and the prevention of agglomeration of the sericite by nitrate during comminution was considered to be another reason for the enhanced grindability by CADC.View full abstractDownload PDF (607K) -
Hisato EITOKU, Mitsuaki HIROTA, Michitaka SUZUKI, Toshio OSHIMA1994 Volume 31 Issue 9 Pages 652-657
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSJanssen's equation is applied to estimate the pressure of the fine powder contained in a bin. In the storage of fine powder, the void fraction varies with the depth of the bed. The mechanical properties of the bed, such as cohesions and the ratio of the horizontal stress to the vertical stress, depend on the void fraction of the bed. To estimate a powder pressure using Janssen's equation, these mechanical properties are expressed as a function of the major principal stress acting on the bed. Powder pressures are calculated for the bed conditions of both plastic equilibrium and dynamic friction. Experimental results show that the powder pressures are in the range of the estimated values.View full abstractDownload PDF (604K) -
Hiroshi SAKAMOTO1994 Volume 31 Issue 9 Pages 658-662
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSA granulator was developed which could produces granules with a smooth surface and narrow particle size distribution in order to improve coating efficiency. This study reports on the granulation process using the new granulator.
For evaluation of granules obtained by altering process parameters as cores for coating, the shape, apparent specific gravity, particle size and fractal dimension were examined.
The following condition were found to be essential to obtain granules suitable for subsequent coating process:
1) The size of spray mist should be kept in the range of 40μm
2) The moisture content of the fluid bed should be made as high as possible provided that good fluidization can be maintained.View full abstractDownload PDF (572K) -
Kazunori SAKAMOTO, Yoriko TAKAI, Keijiro TERASHITA1994 Volume 31 Issue 9 Pages 663-667
Published: 1994
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSMagnetic powder and a binder were continuously kneaded by the twinscrew extruder under various condition. The kneaded mixture was diluted and dispersed to make magnetic paint. The kneading and dispersion state was evaluated as a coated magneic film by gloss, magnetic characteristic, surface roughness, and electromagnetic characteristics. The toughness of the magnetic film was evaluated by density, and dynamic modulas.
As a result, the magnetic powder was well-dispersed by high shear kneading at the high motor output of the extruder, and the surface roughness, magnetic and electromagnetic characteristics were improved. The magnetic powder was densely packed improving the density of the magnetic film. Especially, the dynamic modulas was greatly improved at a high temperature. This indicates that there is an improvement in the durability of magnetic tape at the high temperature.View full abstractDownload PDF (649K)
- |<
- <
- 1
- >
- >|