Micro and mesoporous molded activated carbon was fabricated from rice husk and beet sugar. The material properties of the rice husk and beet sugar based activated carbon were analyzed. The fabricated granular rice husk activated carbon and commercial microporous granular coconut shell activated carbon were tested to remove aromatic sulfur compounds of benzothiophenes and dibenzothiophenes from commercial kerosene. Fixed-bed flow tests were conducted, providing the breakthrough curves for benzothiophenes and dibenzothiophenes. The adsorption isotherms for benzothiophenes and dibenzothiophenes were also obtained in a batch-mode, correlating with the results of the fixed-bed flow test. Both the activated carbons were useful to remove them. The rice husk activated carbon showed a lower-selectivity for dibenzothiophenes, but a higher-selectivity for benzothiophenes, than the coconut shell activated carbon.

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A carbon/silica composite (CSC) designed for use under sliding and compressive load was fabricated from rice husk (RH), an agricultural waste material, without using any binders. A compression pressure of 100 MPa was applied to the RH powder heated from room temperature to 150°C firstly, and then that heated at 280°C for 10min secondly. The RH powder was finally heated from280 to 500°C without compression, producing the precursor of CSCs. The CSCs were produced by sintering the precursor in an electric furnace at 800, 1000, 1200, and 1400°C without compression, innitrogen gas. The CSC sintering at 800°C for 1 h in nitrogen gas provided the maximum bulk density of 1.52 g/cm³. The maximum compressive strength was measured to be 55.7 MPa at the sinteringtemperature of 1200°C. The maximum Vickers microhardness at the surface of 476 appeared on the CSC produced at the second compression pressure of 200 MPa and then sintered at 800°C . The CSC sintered at 1000 °C showed the static friction coefficient of 0.15 and the dynamic friction coefficient of 0.05 under the contact with SUS304 stainless steel.

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Lead of aluminum electrolytic condenser is composed of Sn plated Fe wire (named CP wire) and pure Al wire. Those wires are welded by an arc-stud welding method. The tops of both wires are melted by arc energy and bonded by percussive pressure in this welding method. This paper deals with the microstructure of the interface of Fe/Al and the influence of Sn with the microstructure. From the results of TEM observation and LEED analysis, it was found that the intermetallic compound was formed at the interface of Fe/Al. The intermetallic compounds formed at the interface were FeAl₃ and Fe₂Al₅. This layer thickness was less than 1.5μm. The intermetallic compounds were produced by the diffusion Fe to Al side. The intermetallic compound were not contained Sn. Sn remained at the melting area of Fe wire as the intermetallic compound with Cu. Sn was not diffuse into Al side. In case of using Sn-less Fe wire, the microstructure of the interface of Fe/Al was equivalent to that of Sn plated Fe wire. It was considered that the microstructure of the interface of Fe/Al was not influenced by Sn.

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An evaluation method for contact of solid materials is proposed. Second harmonic ultrasonic component (SUHC) is detected to extract the information of interface of two glass plates. Dependence of second harmonic component (2MHz) for contact force (1-9 N), percentage of adhesive area (0-90%) and vibration amplitude (10nm-110nm) are respectively measured. As the results, nanometer order irregularity of the surface of contact becomes the source of SUHC and is strongly affected the second harmonic components ; SUHC is lineally increased to the contact force and is also increased to the percentage of tight adhesive area. Moreover, increase of SUHC is slight dependent to the vibration amplitude for healthy contacts, but has relatively strong dependency to the contact without contact agent. Necessity of explanation for behavior of SUHC should be considered at the view point of the sound reflection and transmission at the nanometer order gap between two glass plates are also suggested.

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Comminution is an important mechanical operation in the many industries that treat partiulate solid materials. The grindability or the grinding resistance (e.g. Work index, Hardgrove grindability index) of the solid material are useful for evaluating the energy efficiency of the grinding processes, the grinding circuits and the grinding machines. It is difficult to measure the grindability from the point of the view of the measuring processes, time or the cost of the testing machine. Measuring powder properties (ex. void fraction, angle of repose) is easy in comparison with determining or grinding resistance.
We investigated the relationship between powder property and grindability in a particulate solid aterial. The solid material used was mono-sized quartz particles which were classified by dry and wet creening. The powder properties measured were the void fractions of the particle bed, with and without tapping, and the angle of repose of the particles. The grindability was defined by the mass of ground products less than the feed size per unit of crushing energy. This was determined by the compressive crushing test of the particle bed. We were able to define the correlation between the powder properties tested and the grindability; that is, we found that it was possible to evaluate the grindability or the grinding resistance of a particulate material by measuring the powder properties.

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