All issues
Volume 32 (1992 - 199･･･
- Issue 4 Pages 217-
- Issue 3 Pages 153-
- Issue 2 Pages 69-
- Issue 1 Pages 3-
Volume 32, Issue 4
Displaying 1-7 of 7 articles from this issue
- |<
- <
- 1
- >
- >|
-
Kakuzo TADA1993 Volume 32 Issue 4 Pages 217-229
Published: March 25, 1993
Released on J-STAGE: September 20, 2011
JOURNAL FREE ACCESSProgress of chemical analysis of clays and similar materials is reviewed in this paper. The rapid methods used in geochemistry and ceramic industry are outlined, and a brief history of the standard methods of chemical analysis of refractory materials in ASTM, BS, DIN and JIS is described.View full abstractDownload PDF (824K) -
Tatsuro KAWASHIMA1993 Volume 32 Issue 4 Pages 230-238
Published: March 25, 1993
Released on J-STAGE: September 20, 2011
JOURNAL FREE ACCESSSome of the information by activation analysis of clay minerals are reviewed. They are classified as follows.
1. District characteristic of elemental concentration among the pottery stones.
2. Elemental concentration among clay minerals of the layer in the Naegi deposit.
3. Elemental concentration among clay minerals of the layer in the Seto deposit.
4. Variation of elemental concentration by classification samples by elutriation of the Sodo.
5. Variation of elemental concentration by hydrothermal alteration action on the formation of the Amakusa pottery stone deposit.
6. Variation of elemental concentration by hydrothermal multistage alteration actions on the formation of the Itaya kaolin deposit.
7. Several patterns observed for the concentration of rare earth elements on the clay minerals.
8. District characteristic by elemental concentration on clay mineral of the Seto region.View full abstractDownload PDF (710K) -
Shinji TOMURA1993 Volume 32 Issue 4 Pages 239-246
Published: March 25, 1993
Released on J-STAGE: September 20, 2011
JOURNAL FREE ACCESSRecent progresses in particle-size analysis are reviewed and the matters that require attention to apply these method for clay partcles are discussed. Usually, clay partilces have unfavorable properties for particle analysis, such as submicron diameter, low sphericity, wide particle-size distribution and strong coagulation. To overcome these difficulties, it was suggeted that the folloing attentions are required for the applications for clays: 1) return back to the physical meaning of the particle-size measured by each method, 2) check the particle-size with electron microscope, 3) break coagulations using appropriate dispersant and ultrasonic wave and 4) check the reproducibility of the sizes several times with different treatment utilizing recent instrument with rapid analysis.View full abstractDownload PDF (888K) -
Norihiko KOHYAMA1993 Volume 32 Issue 4 Pages 247-258
Published: March 25, 1993
Released on J-STAGE: September 20, 2011
JOURNAL FREE ACCESSRecent transmission electron microscope (TEM) can analyze many kinds of secondary emissions, such as elastically and inelastically scattered electrons, unscattered energy-loss electrons, backscattered and secondary electrons, Auger electrons and emitted X-rays, from the specimen in a single instrument. In addition to these functions, many kinds of instruments being controlable specimen environments, such as temperature from an ultra-low to high, humidity, pressure of air and/or gas, and others, have been developped without decreasing the capabilities of TEM itself. This kind of TEM has become popular for the study of clay science and has succeeded in multiple types of measurements on the same clay mineral grain. This paper describes the recent development of like this multi-functions (MFs) TEM and its contribution to clay mineralogy:(1) resolution of MFs-TEM, (2) EDX detector with Ultra-thin window (UTW), (3) countermeasure for beam damage reduction, such as employment of low-dose unit system, high sensitibity imaging plate (IP) and TV system, and cryotransfer holder (at low temperature of liquid He or N2), (4) environmental cell method, (5) observation method of suraface charge and AFM, (6) quantitative particle counting method by TEM and the specimen preparation technique. TEM is only one of many instruments available today for the study of clay science but it is also hoped that a new aspect will be opened by the use of MFs-TEM for clay science.View full abstractDownload PDF (14945K) -
Mitsuo SATO1993 Volume 32 Issue 4 Pages 259-263
Published: March 25, 1993
Released on J-STAGE: September 20, 2011
JOURNAL FREE ACCESSBoth X-ray Rietveld and profile fitting structure analyses have been reviewed and discussed on the problems in the application to clay mineral samples. Both methods have established their positions in the crystal structure analysis of powder samples, but in the clay mineral samples, several characteristic features, which are inherent to clay minerals such as orientation effect and low symmetry in the sheet structure, have prevented to disclose the detailed structure of them. In order to overcome the problems, it is suggested to introduce more reliable synchrotron X-ray data as well as other auxiliary data, which is now popular in the field of zeolite structure analysis.
Finally, on the most fundamental problem of the crystal structure analysis, a local structure determined by X-ray method is compared and discussed with the result from molecular dynamic simulation.View full abstractDownload PDF (439K) -
Satoru UEDA, Naohito FUKUYA, Koichi NIIHARA1993 Volume 32 Issue 4 Pages 264-271
Published: March 25, 1993
Released on J-STAGE: September 20, 2011
JOURNAL FREE ACCESSSilicalite 2, ZSM-11, Ga-ZSM-11 and Ga, Al-ZSM-11 solid solution were hydrothermally synthesizd using silicon powder (99.999%) as a silica source. The SiO2/Al2O3 molar ratio of Silicalite 2 was highly siliceous to be 2×105. The maximum Ga and Al contents for end-members were 2.62Ga and 2.40Al/u.c., respectively.
Crystal shape and dimension of products varied depending on initial H2O content. Large prismatic crystals up to 20μm were grown with the increase of H2O content, whereas small spherulites (few μm) composed of lath-like crystals of several hundreds were formed in low H2O contents.
Synthesized Ga, AI-ZSM-11 can be regarded as nearly ideal solid solution between Ga and Al at oms from the variation of Ga2O3/(Al2O3+Ga2O3) molar fraction. This indicates that there is no site preference between both elements in ZSM-11 structure.
DTA profiles of products showed exothermic peaks ranging from ca.200 to 550°C by the thermal decomposition of TBA. They varied depending on only the Ga and Al contents of end-members, regardless of the difference in chemical element. As a results, it is not easy to distinguish between both the end-members from the DTA patterns. Similarly the DTA curves of solid solution varied only with the (Ga+Al) contents, regardless of changing Ga/Al (or Al/Ga) ratio. This idicates that there is little difference between TBA-Ga interaction and TBA-Al one in ZSM-11 strucure.View full abstractDownload PDF (4848K) -
Effects of Hydogen Ion-Exchange on the Dispersion State and Chemical StabilityTsuyoshi HAYASHI, Chong Tak SONG, Ken-ichiro SUGIMORI, Kiyoshi ASAGA, ...1993 Volume 32 Issue 4 Pages 272-280
Published: March 25, 1993
Released on J-STAGE: September 20, 2011
JOURNAL FREE ACCESSEffects of ion-exchange reaction of interlayer Na by hydogen ion in aqueous suspensions of sodium fluor-tetrasilicic mica (Na-TSM) on the dispersion state and chemical stability of it were studied. Na-TSM suspensions with appropriate solid concentration form stable dispersion, where a part of Na ions of Na-TSM diffuse into a bulk solution along with OH ion arised from Donnan hydrolysis and act as counter ion leading to the formation of thick electric double layer.
With respect to pH condition, weak aggregation is formed in the suspensions adjusted at pH 9-5 and strong flocculation occurs in those with pH value below 4, while good dispersion is attained at pH 10-12. Hydrogen (H) ion in the aqueous system is not only apt to adsorb in the double layer by displacing Na but is also able to displace Mg in octahedral lattice. Such H-TSM suspensions that prepared by dialysis and ionexchange treatment using H-resin are unstable, since the crystal structure is collapsed by H ion in the interlayer as the time proceeds. As thinner is the solid concentration, amount of H ion is increased per unit weight of Na-TSM, dispersion tends to be unstable by similar reasoning.
On the other hand, H-TSM suspensions are changed to good dispersion by adding NaOH to a pH value over 10. Addition of sodium salts such as phosphate, sulfate and chloride also improves the dispersing state due to the action lowering H ion concentration in the double layer together with supplying Na. Sodium phosphate acts as a good dispersing agent increasing pH value by hydrolysis and removing Mg from the double layer by complex formation.View full abstractDownload PDF (4007K)
- |<
- <
- 1
- >
- >|