Abstract: An optical recording medium of phase change type wherein favorable recording/reproducing properties are realized in high density recording, in particular, when the minimum mark length is up to 0.6 &mgr;m and the track pitch is up to 0.7 &mgr;m is provided. An optical recording method wherein high transfer rate is realized in the use of such high density recording medium is also provided. The optical recording medium has a recording layer having a thickness dr of 10 to 18 nm, and the first dielectric layer comprises one or more unit dielectric layers and the number of the unit dielectric layers is m (m: an integer of 1 or more).

Abstract: An optical recording medium having at least a light-transmitting substrate, a recording layer recorded by heat mode recording, and a reflective layer comprising a metal or a semimetal disposed in this order exhibiting reduced signal noise in the reading and improved recording characteristics are provided. A method for producing such optical recording medium is also provided, and this method includes the step of changing bonding state of the element(s) constituting the reflective layer at least in the area to be recorded.

Abstract: Noise of the read-out signal is reduced in an optical information medium comprising a supporting substrate and a reflective layer disposed on the supporting substrate wherein the reading beam irradiates the medium from the side where the reflective layer is formed. In addition, noise of the read-out signal is reduced without adversely affecting the recording properties in an optical information medium comprising a supporting substrate, and a reflective layer and a recording layer disposed on the supporting substrate in this order wherein the recording beam irradiates the medium from the side where the reflective layer is formed. In the medium, the reflective layer has a crystallite size of up to 30 nm.

Abstract: In an optical recording medium of land/groove recording system, a sufficient tilt margin and a reduced cross talk are realized simultaneously with a sufficiently increased output.

Abstract: An optical recording medium of phase change type is provided. In this medium, cross erase is sufficiently suppressed and favorable recording/reproducing properties are realized in high density recording, and in particular, when the track pitch is less than 0.7 &mgr;m. The medium comprises a substrate, and a first dielectric layer, a recording layer of phase change type, a second dielectric layer, and a reflective layer disposed on the substrate in this order, and the recording layer has a crystallization temperature of at least 160° C., and the second dielectric layer has a thermal conductivity higher than that of the first dielectric layer.

Abstract: An optical recording medium comprising a substrate, at least one dielectric layer and a phase change type recording layer. In overwriting, the recording medium should satisfy the condition V.sub.OW /V.sub.OP <1, preferably 0.5.ltoreq.V.sub.OW /V.sub.OP <0.95, where V.sub.OP is the optimum linear velocity and V.sub.OW is a linear velocity for overwriting. This enables the erasability of recorded marks on the medium to be at least 26 dB after the recording medium with the recorded marks has been stored for at least 100 hours at 60 to 80.degree. C.

Abstract: The invention provides a method of fabricating an optical recording medium comprising a phase change type recording layer containing at least one element selected from In, Ag, Te and Sb. The recording layer is formed by a sputtering technique wherein sputtering is carried out while an inert gas and an oxygen gas are introduced in a vacuum chamber in a sputtering system, so that the number of overwritable cycles can be increased by simple means.

Abstract: A phase change type optical recording medium of Ge--Sb--Te system wherein number of overwritable operation has been increased is provided. The optical recording medium has a substrate and a recording layer of phase change type on the substrate, and the recording layer contains Ge, Sb and Te as its main elements, and at least one of Ag and Au in total content of 0.2 to less than 2.5 at % (excluding 2.5 at %).

Abstract: An optical recording medium of phase change type which exhibits an increased number of overwritable operations is provided. The optical recording medium comprises a substrate, and a first dielectric layer, a recording layer, a second dielectric layer, and a metal reflective layer disposed on the substrate in this order, and the first dielectric layer comprises a dielectric layer 1a on the side of the substrate and a dielectric layer 1b in contact with the recording layer. The dielectric layer 1a comprises ZnS--SiO.sub.2, and the dielectric layer 1b comprises Si.sub.3 N.sub.4 and/or Ge.sub.3 N.sub.4. The second dielectric layer may comprise a single layer of ZnS--SiO.sub.2, SiO.sub.2 or oxide of a rare earth metal. The second dielectric layer may also comprise a laminate of a dielectric layer 2a comprising ZnS--SiO.sub.2 on the side of the substrate and a dielectric layer 2b comprising SiO.sub.2 or oxide of a rare earth metal on the side of the reflective layer. The dielectric layer 1b has a thickness of 0.

Abstract: A method for preparing an optical recording medium of phase change type is provided. This recording medium comprises a substrate, a recording layer, and a lower and an upper dielectric layers provided in direct contact with the recording layer. In this method, a step of an exposure treatment wherein the surface of the lower dielectric layer is exposed to an oxidative atmosphere is conducted after forming the lower dielectric layer on the substrate and before forming the recording layer on the lower dielectric layer. A step of a heat treatment wherein said lower dielectric layer is heat treated may be carried out in addition to the exposure treatment.

Abstract: The invention provides a phase charge type optical recording medium comprising on both sides of a recording layer dielectric layers, each containing zinc sulfide and silicon oxide as main components. The medium comprises on a substrate 2 a first dielectric layer 31, a recording layer 4, a second dielectric layer 32 and a reflective layer 5 made up of a metal. The first dielectric layer 32 comprises a dielectric lamina 1a on a substrate 2 side thereof and a dielectric lamina 1b on a recording layer 4 side thereof. The dielectric lamina 1a has a silicon oxide content of 2 to less than 40 mol %, the dielectric lamina 1b has a silicon oxide content of 40 to 100 mol %, and the second dielectric layer 32 has a silicon oxide content of 2 to 50 mol % and a thickness of 10 to 35 nm. The number of overwritable cycles can be increased.

Abstract: An optical recording medium comprises a substrate and a multilayer structure on the substrate. The multilayer structure comprises a phase change type recording layer and a pair of dielectric layers, at least one of which contains zinc sulfide optionally with silicon oxide. When a depth profile of the multilayer structure in a thickness direction thereof is found by Auger electron spectroscopy, a region having an intensity ratio S/Zn of 2 or lower exists across a thickness of at least 6.0 nm, calculated as SiO.sub.2, from the vicinity of an interface between the dielectric layer and the recording layer into the recording layer. In the vicinity of the interface between the dielectric layer and the recording layer, there is also a region having an intensity ratio S/Zn vs. O/Si relation that satisfies S/Zn<O/Si.

Abstract: An optical recording medium of phase change type with an increased number of overwritable operations and method for preparing such an optical recording medium is provided. In the optical recording medium of phase change type whose rate determining stage in the production has been the initialization of the recording layer, the time required for the production is reduced, and stable recording/reproducing properties are realized from the first overwriting operation. The optical recording medium comprises a transparent substrate and a recording layer on the transparent substrate.

Abstract: A combined fuel cell/gas turbine power generation system includes a fuel cell, a reformer connected to the fuel cell for producing a hydrogen rich reformed gas by steam reforming and feeding the reformed gas to the fuel cell, an air compressor having an electric motor which drives the air compressor, the air compressor compressing air taken from open air and feeding a pressurized air to the fuel cell, a gas turbine which is connected to the fuel cell and generates power using, as a working fluid, an exhaust combustion gas from the reformer obtained by burning an off gas and off air from the fuel cell, and a generator which is coaxially connected to the gas turbine and driven by the axial output power of the gas turbine, the generator generating power with the axial output power of the generator, the output power of the generator driving the electric motor in the air compressor.

Abstract: An endothermic reaction apparatus for converting a raw gas, or a feed gas, into a reaction gas or a produced gas, under the influence of an endothermic reaction catalyst includes a reaction tube having a pair of inner and outer vertical tubular spaces which are separated by a vertical partition wall and communicate with each other at their lower ends. The endothermic reaction catalyst is disposed in the inner and outer tubular spaces to form a continuous catalyst structure. The catalyst structure has an inlet portion for introducing the raw gas into the catalyst structure and an outlet portion for discharging the reaction gas from the catalyst structure. The inlet and outlet portions of the catalyst structure are disposed generally at the same level. A burner is disposed inwardly of the inner tubular space for heating the catalyst structure.

Abstract: A direct contact type multi-stage steam condenser system having a direct contact type high vacuum stage steam condenser disposed above a low vacuum stage steam condenser with a water supplying tank for the low vacuum stage condenser disposed therebetween. In the preferred embodiment, the high and low vacuum stage condensers and the water supplying tank are formed integrally as a single unit. The water supplying tank, which also serves as a gas-tight seal between the condenser stages, is formed above a water sprinkling board provided in the upper portion of the low vacuum stage condenser. Condensed water falls under its own weight thereby eliminating the need for an intermediate pressurizing pumps.