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Volume 36, Issue 5
Displaying 1-5 of 5 articles from this issue
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Shuhei SHIOJI, Masashi KAWAGUCHI, Yasuhiro HAYASHI, Kenjiro TOKAMI, Hi ...1999 Volume 36 Issue 5 Pages 352-362
Published: May 10, 1999
Released on J-STAGE: July 01, 2010
JOURNAL FREE ACCESSIrreversible adsorption of methanol vapor on sillica surface was studied through the measurements of adsorption isotherms and IR absorption as well as differential thermal analysis. Dependencies of irreversible methanol adsorption on the preheating temperature and the vapor pressure was investigated to evaluate the reactivity of silica surface.
The irreversible adsorption occurs by two mechanisms, i. e., formation of hydrogen bond and surface methoxylation reaction which forms methoxy groups. DTA profiles of methoxy groups reflects the states of hydroxyl groups on the surface. Isolated methoxy groups exhibited DTA exothermic peaks at higher temperature. They were formed from the isolated hydroxyl groups on the surface preheated at temperatures above 400°C. The surface methoxylation reaction occurred mainly on the isolated hydroxyl groups at a low pressure, while methoxylation of siloxane bridges took place at a pressure higher than that of multilayer formation and was promoted by the methanol vapor condensation in the pores.View full abstractDownload PDF (1373K) -
Hiroshi TSUNAKAWA1999 Volume 36 Issue 5 Pages 363-367
Published: May 10, 1999
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSIn order to estimate flowability of a cohesive powder, an expression was proposed for a ratio of strength to unit weight as a function of compression stress of powder. The expression was verified with experimental data of various strengths measured by tensile test, shear test, compression test and other tests as shown in many previous papers.
In the special case of that the strength identified with the compression stress, an equation was obtained between the compression stress and the packing fraction of the powder. The strength therefore was shown by a power function of the packing fraction alone with a favorable comparison between experimental previous data. A conclusion was shown that the strengths, the compression stress and the packing fraction were mutually related.View full abstractDownload PDF (577K) -
Hiroyuki TSUJIMOTO, Toyokazu YOKOYAMA, Isao SEKIGUCHI1999 Volume 36 Issue 5 Pages 368-377
Published: May 10, 1999
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSA new granulation technique employing a spray fluidized bed granulator, which directly produces granules from liquid materials, was proposed. Instant coffee dissolved in water was used as a liquid material. In order to clarify the agglomeration mechanisms in the granulator, changes in physical properties of granules were measured at various feed rates of liquid materials. We proposed an index R which is related to the liquid feed rate and is capable of evaluating the drying condition in the granulator quantitatively.
Through the experimental results, it was found that the granule formation proceeds depending on the R value by the following three granulation mechanisms; 1) generation of fine particles by spray drying effect, 2) agglomeration of fine particles, and 3) layering of fine particles onto the surface of individual agglomerates.
Spherical granule products with a high bulk density were obtained especially by the layering granulation in a stable fluidized bed. Further the growth of granules during the layering granulation was well described by an equation derived from the mass balance for coffee solids in the granulator.View full abstractDownload PDF (3077K) -
Katsumi HIGASHI1999 Volume 36 Issue 5 Pages 378-386
Published: May 10, 1999
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (1224K) -
Saburo YASHIMA1999 Volume 36 Issue 5 Pages 387-395
Published: May 10, 1999
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (2521K)
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