Abstract: An annealing separator used for manufacture of the grain-oriented electrical steel sheet according to the present invention contains MgO, at least one or more types of compounds of metal selected from a group comprised of Y, La, and Ce, at least one or more types of compounds of metal selected from a group comprised of Ti, Zr, and Hf, and at least one or more types of compounds of metal selected from a group comprised of Ca, Sr, and Ba, when a content of the MgO in the annealing separator is defined as 100% by mass %, a total content of the compounds selected from a group comprised of Y, La, and Ce converted to oxides is 0.8 to 8.0%, a total content of the compounds of metal selected from a group comprised of Ti, Zr, and Hf converted to oxides is 0.5 to 9.0%, and a total content of the compounds of metal selected from a group comprised of Ca, Sr, and Ba converted to sulfates is 0.5 to 8.

Abstract: An annealing separator used for manufacture of the grain-oriented electrical steel sheet according to the present invention contains MgO, at least one or more types of compounds of metal selected from a group comprised of Y, La, and Ce, and at least one or more types of compounds of metal selected from a group comprised of Ti, Zr, and Hf, when a content of the MgO in the annealing separator is defined as 100% by mass %, a total content of the compounds of metal selected from a group comprised of Y, La, and Ce converted to oxides is 0.5 to 6.0% and a total content of the compounds of metal selected from a group comprised of Ti, Zr, and Hf converted to oxides is 0.8 to 10.0%, a mean particle size of the compounds of metal selected from a group comprised of Y, La, and Ce is 10 ?m or less, a ratio of a mean particle size of the compounds of metal selected from a group of Ti, Zr, and Hf to the mean particle size of the compounds of metal selected from a group comprised of Y, La, and Ce is 0.1 to 3.

Abstract: An annealing separator used for manufacture of the grain-oriented electrical steel sheet according to the present invention contains MgO, at least one or more types of compounds of metal selected from a group comprised of Y, La, and Ce, and at least one or more types of compounds of metal selected from a group comprised of Ti, Zr, and Hf, wherein when a content of the MgO in the annealing separator is defined as 100% by mass %, a total content of the compounds of metal selected from a group comprised of Y, La, and Ce converted to oxides is 0.5 to 8.0%, a total content of the compounds of metal selected from a group comprised of Ti, Zr, and Hf converted to oxides is 0.5 to 10.0%, further, a total of a total content of the compounds of metal selected from a group comprised of Y, La, and Ce converted to oxides and a total content of the compounds of metal selected from a group comprised of Ti, Zr, and Hf converted to oxides is 2.0 to 14.

Abstract: When the trigonometric function of the phase lag of the hydraulic excitation of the runner vanes, which varies in accordance with the combination of the number of runner vanes and the number of guide vanes of a high head pump/turbine, is denoted by cos(.theta..sub.R n), the thickness of the crown along a circle of a diameter at a mid point of the diameter of the outermost periphery of the runner is denoted by t.sub.MC, the thickness of the band is denoted by t.sub.MB, the mean thickness of the crown at the outer peripheral portion of the runner is denoted by t.sub.C, the mean thickness of the band is denoted by t.sub.B, and the rigidity ratio of the crown and band to the runner vane is denoted by K.sub.R taking the rigidity of the runner vane as a reference, the moment coefficient C.sub.MO which is a function of cos(.theta..sub.R N) and the rigidity ratio K.sub.R is selected to be less than 0.5 in accordance with the value of cos(.theta..sub.R n), and relations t.sub.C /t.sub.MC .ltoreq.1 and t.sub. B /t.sub.

Abstract: An air-fuel ratio control apparatus for an alcohol engine driven by fuel containing an alcohol component, where oxygen density of the exhaust gas is detected by an O.sub.2 sensor and an air-fuel ratio is controlled to approach a theoretical air-fuel ratio in response to the oxygen density detected by the O.sub.2 sensor, is disclosed. The apparatus comprises an engine load detecting means for detecting engine load, and a control unit for correcting the air-fuel ratio to be rich in response to engine load such that the degree of the correction becomes larger as the engine load becomes small.

Abstract: A multistage hydraulic machine in which respective pressure stages are connected in series through return passages and the highest and lowest pressure stages of the hydraulic machine are provided with movable guide vanes the degrees of openings of which are variable is controlled for load regulation or water flow rate regulation under a normal operation condition of the hydraulic machine by controlling degrees of openings of the movable guide vanes of the highest and lowest pressure stages in accordance with several control modes.

Abstract: A multi-stage hydraulic machine includes a rotatable shaft, a plurality of runners fixed to the shaft and arranged from a highest-pressure stage to a lowest-pressure stage, runner chambers which respectively house the runners, a return channel for connecting adjacent ones of the runner chambers with each other, movable wicket gates provided at least in the runner chamber of the highest-pressure stage and capable of moving between a position in which the movable wicket gates block the channel and a position in which said movable wicket gates open the channel, and a draft tube connected to the runner chamber of the lowest-pressure stage.

Abstract: A multistage hydraulic machine in which respective pressure stages are connected in series through return passages and the highest and lowest pressure stages are provided with movable guide vanes the degrees of openings of which are variable is controlled in load adjustment or in response to the change of a static head under a steady operation condition by controlling the degrees of openings of the movable guide vanes of the highest and lowest pressure stages in accordance with several modes.

Abstract: A multistage hydraulic machine which includes a housing, a main shaft mounted in the housing, a high-pressure stage and low-pressure stage runner firmly secured to the main shaft wherein the housing has formed therein a plurality of runner chambers enclosing each of the runners, respectively, of the high-pressure and the low-pressure stage, a return passage communicating with the runner chambers of the high-pressure and low-pressure stages, a high-pressure stage, outer back chamber, a high-pressure stage, inner back chamber and a high-pressure stage, side chamber all of which are located within the runner chamber enclosing the high-pressure stage runner, a low-pressure stage, side pressure chamber located within the runner chamber enclosing the low-pressure stage runner, a mechanism for communicating the high-pressure stage, inner back chamber with the return passage, and a mechanism for respectively communicating the low-pressure stage, side pressure chamber with the return passage.

Abstract: A multistage hydraulic machine such as a pump/turbine having at least three pressure stages in which the highest and lowest pressure stages are provided with movable guide vanes the degree of opening of which are variable, and the other intermediate pressure stages are provided with stationary guide vanes the degree of opening of which are not variable. The movable and stationary guide vanes are simultaneously or independently controlled in accordance with a change of an operational condition at the time of steady operation in a manner such that the degree of opening of the movable guide vanes of the lowest pressure stage becomes relatively larger or smaller than that of the stationary guide vanes in a high flow-rate range or in a low flow-rate range, respectively, while maintaining the degree of opening of the movable guide vanes of the lowest pressure stage to be equal to or smaller than that of the highest pressure stage.

Abstract: In a multistage hydraulic machine of the type having a main shaft supporting a plurality of runners ranging from a highest pressure stage to a lowest pressure stage, at least one set of adjustable wicket gates provided for the highest pressure stage runner, a draft tube connected to a lower end of the lowest pressure stage runner, and devices for supplying and exhausting compressed air into and out of the pressure stages upon closure of the wicket gates, there is provided an air exhausting device including an air exhausting passage opening in a runner-cone portion of the lowest pressure stage runner.

Abstract: Disclosed is a multistage hydraulic machine system which comprises a multistage hydraulic pump/pump-turbine including a highest-pressure stage having movable guide vanes with variable opening of water path arranged round a runner and a lower-pressure stage or stages having fixed guide vanes with fixed opening of water path arranged round a runner or runners, and a control unit for controlling the operation of the multistage hydraulic pump/pump-turbine, whereby the opening of the movable guide vanes is controlled by the control unit so that such opening is larger than that of the fixed guide vanes for a large-flow normal operation of the pump/pump-turbine and smaller for a small-flow normal operation.

Abstract: The side housing of a rotary piston engine has an inner surface which has been subjected to a soft-nitriding treatment to form a layer of Fe-C-N type compounds and thereafter ground to provide a surface roughness of between 0.3 and 15 microns. An oil seal which slidably engages the inner surface of the side housing has a sealing lip constituted by a chromium plating. The arrangement provides an improved wear resistance of the oil seal.