摘要:
Turbostratic boron nitride (t-BN) powder having excellent sinterability. A mixture of boric acid anhydride and urea is charged in a reaction vessel together with alkali-borate, heated step by step in the vessel in an nonoxidizing gas atmosphere of one atmospheric pressure or above, and kept at a temperature from 850° C. to 950° C. to yield an intermediate product formal substantially of an amorphous boron nitride powder (first reaction step). Then the intermediate product is heated and kept at a temperature from 1200° C. to 1400° C. to crystallize crystalline t-BN, and the product is purified by washing with water and aqueous solution to obtain pure crystalline t-BN powder.
摘要:
An electric apparatus such as an inverter includes a cooler unit including a cooler, and a semiconductor component and an electrical component disposed on two opposite sides of the cooler respectively, and a housing for supporting the cooler unit. The cooler unit is pivotally supported on the housing so as to be taken into and out of the housing. The cooler unit is caused to pivot so as to be taken out of the housing when the semiconductor component is to be replaced.
摘要:
A coating protective film which comprises a substrate, which is made of a colored polyolefin film and has a maximum per cent transmission of ultraviolet within a wavelength range of 190 to 370 nm of not more than 10%, and a pressure sensitive adhesive layer, which is made of a pressure sensitive adhesive containing as the main component at least one of polyisobutylene, butyl rubber and polybutene, satisfies the requirements for weatherability of protective pressure sensitive adhesive film which is temporarily attached to finished automobiles for the purposes of protection of automotive coating during transfer and storage, and is also so excellent in peelability as not to pollute the coating on the automobiles.
摘要:
A method for manufacturing hydrogen storage alloy particles comprises steps of obtaining a melt of the hydrogen storage alloy and pulverizing the hydrogen storage alloy by water atomizing process, whereby the melt is pulverized by contacting or colliding with high-speed jetting thereto to be dispersed in the form of solidified fine particles. By employing an aqueous solution of hypophosphorous acid or an alkali aqueous solution in place of water during the water atomizing process, or by etching the oxide films once formed on the surface of the hydrogen storage alloy particles with an aqueous solution of a strong acid, the thickness of the oxide film can be made thinner, and thus a high discharge capacity of a battery configured with a negative electrode comprising the alloy particles can be realized.
摘要:
The sealed lead acid battery comprises a positive and/or negative electrode made of an active material added with porous polymer particles having an average pore diameter of 0.05 to 10 .mu.m and a particle size of 0.1 to 0.8 mm. The additive amount of the porous polymer particles ranges from 0.2 to 3 wt. %. The active material may be incorporated with porous particles of 0.3 to 5 wt. % previously impregnated therein with sulfric acid. The resultant sealed lead acid battery has a high energy density and is superior in a high efficient discharge characteristic, a cycle life characteristic and a low temperature characteristic.
摘要:
In a traction control device in which an initial control torque of an engine is determined in accordance with an acceleration of the vehicle, when an excessive slipping of driven wheels is detected, a time taken for proceeding of the excessive slipping of the driven wheels from a large slip state to a small slip state is counted by a timer. If such time is smaller than a reference time and a gear ratio of the vehicle is of a first gear shift to provide a low vehicle speed, it is decided that the vehicle is traveling on an upward sloping road, and a lower limit value for defining the initial control torque of the engine determined in an initial control torque calculating means is corrected into an increased value in an initial torque correcting means. This prevents the initial control torque of the engine from being excessively reduced at the start of a traction control. By this construction, it is possible to prevent an initial control torque from being excessively reduced due to a misjudgment of a friction coefficient of a surface of an upward or downward sloping road to insure an acceleratability of a vehicle.
摘要:
A high-frequency choke circuit comprises a dielectric layer covered with grounding conductors, a lead line of high-impedance and at least one capacitance land formed within the dielectric layer, and at least one through-hole connecting the lead line and the capacitance land. The capacitance lands are disposed closer to the grounding conductors, resulting in large capacitances with small areas. The capacitance lands are formed on a layer distant from the layer on which the lead line is formed. Therefore, unnecessary electromagnetic coupling with other circuits formed on the same layer as the lead line can be reduced. The grounding conductors cover both surfaces of the dielectric layers that incorporate the capacitance lands and the lead line to thereby shield the circuit formed in the dielectric layers electromagnetically from outside.
摘要:
Provided is an improved refrigeration system for pre-cooling natural gas or cooling a mixed refrigerant for natural gas liquefaction in a propane refrigeration process widely used for the liquefaction of natural gas. The system comprises a plurality of plate-fin heat exchangers preferably arranged in a parallel relationship for passing a propane refrigerant as a vertical flow and pre-cooling natural gas or cooling a mixed refrigerant for liquefying natural gas, and a thermo siphon drum for the propane refrigerant consisting of a horizontally disposed, laterally elongated tank. Because the passages of the heat exchanger for the natural gas or the mixed refrigerant extend over their entire length in mutually separate relationship, even when the propane refrigerant, the natural gas or the mixed refrigerant is in both gas and liquid phases, a high efficiency of heat transfer can be attained, and the size of the heat exchanger can be reduced. In particular, from an economic view point, it is preferable if the thermo siphon drum serves also as a flash tank.
摘要:
Provided is a method for liquefying natural gas which can be readily adapted to LNG plants of all sizes without requiring expensive and special heat exchangers. The liquefaction of feed gas of natural gas and recycle natural gas is carried out with a single-component refrigerant or a mixed refrigerant in a high temperature stage, and with a substantially isentropic expansion in a low temperature stage, and a non-liquefied part of the recycle gas after the expansion step is pressurized with a compressor and recycled along with a recycle stream of non-liquefied par of the feed natural gas, the liquefied part by the refrigerant exchanging heat with the non-liquefied part stream produced from the substantially isentropic expansion, in a plate-fin heat exchanger or the like. The compressor is driven by the power obtained by the substantially isentropic expansion.
摘要:
A case body composed of upper and lower halves having a main wall in which there is defined at an intermediate portion thereof a pair of drive shaft insertion holes in right and left portions thereof, and the case body includes two pairs of upper and lower flange members inwardly projected from inner peripheral portions of the drive shaft insertion holes continuous with the main wall. A name plate made of a materials harder than the plastic material of the case body, is attached to an outer surface of the main wall including the right and left drive shaft insertion holes, and the name plate has one or more indexes formed on the outer surface thereof and has a pair of right and left shaft insertion openings defined therein. The positions of the shaft insertion openings correspond to the drive shaft insertion holes defined in the case body.