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A new rubber recycling technology to produce a thermoplastic elastomer (TPE) based on ethylene-propylene-diene rubber (EPDM) waste was developed. In this technology, the developed process consists of devulcanization of EPDM waste, blending of the devulcanized EPDM and polypropylene (PP), and dynamic vulcanization of the rubber component. All three are set up in as a continuous process in which the Recycled Rubber based Thermoplastic Elastomer (which is indicated as “RR-TPE” henceforth) is finally obtained. The RR-TPE exhibits elasticity and mechanical properties similar to those of commercial Thermoplastic olefins (TPO). These properties may be due to a suitably formed phase structure. Automotive parts are being developed and are going to be produced with the RR-TPE manufactured by this new technology. This technology will contribute to both protecting the environment and saving resources.

A correlated high-speed image and E-field observation of natural lightning attachment process on a time scale of sub-microsecond has been performed. In one of the observed events, downward stepped leader pulses can be clearly identified either in E-filed or optical signals. When the stepped leader approaches within about three hundred meters of ground, optical pulses begin to appear in the lowest 40 m channel section. These pulses have larger amplitude than the pulses from the downward stepped leader. It appears that these pulses are produced by an upward connecting leader. These facts suggest that the upward connecting leader is also stepped and it could produce even stronger pulses than the corresponding downward leader. The downward stepped leader has a velocity of about 4x106 m/s, while the upward leader has the velocity of about 1.7x106 m/s. The return stroke pulses observed in the E-field and in the optical signal agree well in time but differ in fine structures.

The Mitsubishi GDI engine has adopted a pair of upright intake ports, to induce a rotating in-cylinder flow, reverse tumble, and control air fuel mixing with this flow. The port design of the GDI engine was optimized for achieving a high intensity of the reverse tumble while maintaining a high charge coefficient, by means of modeling of in-cylinder flow and experiment with a steady flow rig. First of all, the ideal design of the upright ports was discussed. It was found that for enhancing the reverse tumble, it is more effective to arrange a pair of the ports parallel, than to arrange them convergent. The parallel arrangement leads to the smoother flows passing through the intake sides of the intake valves, and then descending on the cylinder liner, that is turning toward the rotation direction of the reverse tumble, because of less impingement of the flows through a pair of the valves.

Some special features of cloud-to-ground (CG) lightning discharges in the verge of Qinghai-Tibetan Plateau have been found by using the data from wide-band slow antenna system with 1μs time resolution. It has been found that (CG) lightning usually follows intracloud (IC) discharges. K-changes during the IC discharge part initiate from negative charge region and propagate downward to the lower positive charge region with an average speed of 1.5×107 m/s. The radiation waveforms of return stoke begin with a slow front which last for about 9.4 μs to about half of the field peak amplitude, and the zero-to-peak rise time was 10.9μs for negative first return strokes.

Flow and flame structure visualization and modeling were performed to clarify the characteristics of bulk flow, turbulence and mixing in a four-valve engine to adopt the lean combustion concept named “Barrel-Stratification” to the larger displacement center-spark four-valve engine. It was found that the partitions provided in the intake port and the tumble-control piston with a curved-top configuration were effective to enhance the lean combustion of such an engine. By these methods, the fuel distribution in the intake port and the in-cylinder bulk flow structure are optimized, so that the relatively rich mixture zone is arranged around the spark plug. The tumble-control piston also contributes to optimize the flow field structure after the distortion of tumble and to enable stable lean combustion.

This report concerns the development of a new smoothly curved surface which is capable of producing light diffusion when used as a headlamp reflector.

To support sustained manned activities in an enclosed environment in space vehicles such as the Space Station (SS), a respirable air supply system is essential and optimization should be aimed at in the design of such a system. For cabin air revitalization, it is indispensable to remove carbon dioxide (CO2) and other gaseous contaminants generated from crew and/or non-metalic materials to prevent them from accumulating. In addition to the above functions, oxygen (O2) recovery function using trapped CO2 is indispensable for the Air Revitalization System (ARS) because a reduction of resupply materials from ground is strictly required. This paper presents and an outline of a feasibility study of the ARS in which system optimization is made.