Abstract: A group-IV semiconductor substrate has an inclined front surface, the inclination being toward a direction differing from the <010>crystal lattice direction. The substrate is cleansed by heating in the presence of a gas including a compound of the group-IV substrate element. A source gas of a group-III element is then supplied, forming an atomic film of the group-III element on the substrate surface. Starting at the same time, or shortly afterward, a source gas of a group-V element is supplied, and a III-V compound semiconductor hetero-epitaxial layer is grown. Chemical bonding of the group-III element to the group-IV substrate surface produces a crystal alignment of the hetero-epitaxial layer that leads to improved conversion efficiency when the semiconductor substrate is used in the fabrication of solar cells with compound semiconductor base and emitter layers.

Abstract: To provide a semiconductor device capable of enhancing crystallinity of a semiconductor of a III-V group compound of a nitride system formed on a sapphire substrate and to provide a method of manufacturing the same.

Abstract: The present invention relates to a heat dissipation unit for cross flow type cooling tower with which it is possible to prevent the emission of white vapor without lowering the cooling power of the cooling tower, and also without requiring troublesome routine operation. In order to accomplish the above object, the heat dissipation unit of the present invention comprises filling plates arranged vertically and parallel with each other so as to form spaces therebetween, each of the filling plates having uneven surfaces down which water to be cooled flows when water to be cooled is supplied onto the filling plates, and cowl members disposed between neighboring filling plates, each of the cowl members including a pair of side plate portions having upper ends and a roof portion connecting the upper ends of the side plate portions.

Abstract: Hot water is sprayed to fillers arranged immediately under a hot water vessel through spray ports opened on a lower surface of the hot water vessel. The hot water flowing down along the fillers is cooled through direct contact with ambient air. The cooling tower includes fillers partitioned alternately into permanent wet and wet-dry changeover regions which are mutually isolated for flow passages of the ambient air and spray pipes provided on the lower surface of the hot water vessel exclusively for the wet-dry changeover regions such that the hot water can be sprayed to the wet-dry changeover regions separately from the permanent wet regions. The hot water vessel is supported by the spray pipes. The spray ports of the hot water vessel is communicated only with the permanent wet regions.

Abstract: The present invention relates to a cross flow type cooling tower with which it is possible to prevent the emission of white vapor in cold weather with certainty. In order to accomplish the above object, the cooling tower of the present invention comprises: a heat dissipation unit having filling plates arranged vertically and parallel with each other so as to form dry air passages and moist air passages therebetween, each of the dry air passages and the moist air passages having inner surfaces; water supply means for supplying water to be cooled to the inner surfaces of the moist air passages for cooling the water by contact with air passing through the moist air passage; and water invasion stoppers provided at side ends of the filling plates for preventing the water flowing down the inner surfaces of the moist air passages from invading the dry air passages.

Abstract: The present invention relates to a cross flow type cooling tower with which it is possible to prevent emission of white vapor in cold weather. In order to accomplish the above object, the cooling tower of the present invention is constructed of heat exchange units each of which having plates arranged vertically and parallel from each other so as to form passages therebetween, which are separated into wet air passages and switchable air passages capable of switching from dry air passages and wet air passages; a water bath divided into upper and lower baths by a partition plate with holes, the upper bath is provided with spray nozzles for spraying water into the switchable passages, the lower bath provided with spray nozzles for spraying water into the wet passages.When the weather is warm, hot water is supplied into the upper bath, and both the upper and lower baths are filled with water and cooling is performed in every passage.

Abstract: The present invention relates to a heat dissipation unit for cross flow type cooling tower with which it is possible to prevent the emission of white vapor without lowering the cooling power of the cooling tower, and also without requiring troublesome routine operation. In order to accomplish the above object, the heat dissipation unit of the present invention comprises filling plates arranged vertically and parallel with each other so as to form spaces therebetween, each of the filling plates having uneven surfaces down which water to be cooled flows when water to be cooled is supplied onto the filling plates, and cowl members disposed between neighboring filling plates, each of the cowl members including a pair of side plate portions having upper ends and a roof portion connecting the upper ends of the side plate portions.

Abstract: A highly stiff end mill comprising a shank, a plurality of helix cutting edges on the periphery of the end mill, the end mill being characterized in that a radial rake angle of the helix cutting edges in a cross section perpendicular to the longitudinal axis of the end mill is set in the range of -29.degree. to 0.degree. and a core diameter of the end mill is set in the range of 70 to 90% of the outside diameter of the end mill.By selectively determining the negative rake angle in the range described above, this end mill is applicable to hard materials and has general-purpose properties. The improper factors of the end mill, such as increased cutting resistance, can be compensated for by setting the core diameter thereof to the range described above. This end mill is also structured to be able to cut materials with less hardness values as well as hard materials, thereby covering a wide range of applications.

Abstract: An evaporative emission control system for an internal combustion engine, in which fuel vapors generated in a fuel reservoir are stored in a fuel vapor storage canister when the engine is stopped so that the fuel vapors may be used when the engine is in operation. A purge control valve is disposed on a discharge port of the canister. The purge control valve is designed so that it is not opened unless a temperature of the engine exceeds a level above a predetermined threshold even when the engine is in operation. When the engine is operated at a low temperature, the stored fuel vapors in the canister are not released for stabilization in the air-fuel ratio of a mixture fed to the engine, and when the engine is operated at a high temperature, the stored fuel vapors are released into the engine to effectively consume the fuel.

Abstract: An ignition timing control system for an internal combustion engine, including a vacuum actuator connected to turn a point base about the axis of the rotary cam which operates the breaker points to advance or retard the ignition timing. The vacuum actuator employs two vacuum chambers, one used primarily to advance the timing, the other used to retard the timing. Each chamber communicates with an engine intake passage downstream from a throttle valve. Electromagnetic selector valves, one associated with each vacuum chamber, serve to connect each vacuum chamber to the engine intake passage, or alternatively to vent each vacuum chamber to atmosphere. These selector valves may be energized by a temperature switch, a velocity switch or a cruise switch. A check valve maintains vacuum intensity in the spark advance chamber when the vacuum intensity at the engine intake passage is lowered by virtue of the opening of the throttle valve.