摘要:
A snubber circuit for a GTO thyristor including a series-connected member of a capacitor and a diode connected in parallel with a GTO thyristor and a series-connected member of a resistor and a thyristor connected in parallel with the diode. The thyristor is adapted to be turned on when the GTO thyristor is turned on and the thyristor is adapted to be turned off at the same time as or immediately after a turn off of the GTO thyristor, whereby the circuit is enabled to perform the same protecting function as that of a snubber circuit for a GTO thyristor which includes no thyristor and, further, to block a discharging current from the capacitor due to the ripple voltages produced across the GTO thyristor after its turn off, by means of the thyristor which is then in an off state, so that no current may flow through the resistor.
摘要:
Flame spraying compositions exhibiting improved adherence to a variety of substrates are disclosed, as well as articles coated with such compositions. The spraying compositions comprise a granulated mixture of two components: (1) a powdery material selected from the group consisting of powdered metals, heat resistant ceramics, cermets, and resins; and, (2) a ceramic needle fiber such as whisker crystals of SiC or Si.sub.3 N.sub.4. Articles coated with thin films of these coatings exhibit increased thermal and corrosion resistance.
摘要:
An electrostatic latent image developing device having a non-magnetic carrier member for carrying a developer and fixed magnets installed inside said carrier member, and a regulating member disposed over the carrier member for regulating a developer layer thickness on the surface of the carrier member at a point between two peaks of a magnetic flux produced by two closely arranged magnets having same polarity inside the carrier member. The regulating member is a doctor blade and the carrier member is a rotatable cylindrical sleeve.
摘要:
A distributorless ignition system in which a primary current alternately changing in its flowing direction is supplied to the primary winding of an ignition coil to induce a high secondary voltage alternately changing in polarity across the secondary winding of the ignition coil, and the induced voltage is sequentially distributed through a plurality of rectifiers such as diodes to a plurality of associated spark plugs thereby sequentially causing jumping of a spark across the spark gap of the spark plugs. An apparatus for mounting such a distributorless ignition system is also disclosed. In the invention, a surge voltage absorber is associated with each of the diodes, so that a surge voltage, which may be induced across the secondary winding of the ignition coil due to failure of normal sparking as when one or more of the spark plugs are removed or excessive wear occurs on the electrodes of one or more of the spark plugs, can be effectively absorbed without the possibility of damage to the diode or diodes and insulating members.
摘要:
Compounds of formula (I): ##STR1## (wherein R represents a group of formula ##STR2## and the corresponding ring-closed lactones, salts (especially alkali metal salts) and esters (especially C.sub.1 -C.sub.5 alkyl esters) thereof may be prepared by subjecting ML-236B, or ML-236B carboxylic acid or a salt or ester thereof to enzymatic hydroxylation, which may be effected by means of microorganisms of the genera Mucor, Rhizopus, Zygorynchus, Circinella, Actinomucor, Gongornella, Phycomyces, Martierella, Pycnoporus, Rhizoctonia, Absidia, Cunninghamella, Syncephalastrum and Streptomyces, or cell-free, enzyme-containing extracts from said microorganisms. The compounds are capable of inhibiting biosynthesis of cholesterol and are thus useful in the treatment of hypercholesteraemia.
摘要翻译:式(I)的化合物:其中R表示式(Ⅰ)的基团或相应的闭环内酯,盐(特别是碱金属盐)和酯(特别是C 1 -C 5) 烷基酯)可以通过使ML-236B或ML-236B羧酸或其盐或酯进行酶羟基化来制备,其可以通过毛霉属,根霉属,丝状芽孢杆菌属,圆弧菌属,放线菌属, 金盏草,植物疫霉,火鸡lla,,us,,,Ab ia,,,,,,and and and。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。
摘要:
Compounds of formula (I): ##STR1## (in which: Z represents a group of formula ##STR2## A represents a group of formula ##STR3## B represents a group of formula ##STR4## R.sup.1 represents a hydrogen atom or a methyl group; R.sup.2, R.sup.3, R.sup.4 and R.sup.6 are the same or different and each represents a hydrogen atom or an acyl group;R.sup.5 represents a carboxy group;R.sup.7 represents a hydrogen atom, an alkyl group or an acyl group;X represents a halogen atom; andthe bond represents a double bond)and salts and esters of the carboxy group represented by R.sup.5 and compounds of formula (II): ##STR5## (in which R.sup.1, is as defined above and R.sup.2 represents an .alpha.-methylbutyryl group; and R.sup.4 represents a hydrogen atom) have useful anti-hypercholesteraemic activity and may be prepared from certain natural products obtainable by cultivation of microorganisms of the genera Penicillium or Monascus.
摘要:
A composite material comprising a fibrous sheet which is impregnated with a polyurethane elastomer. The polyurethane elastomer comprises the reaction product of(A) a polymeric diol having a molecular weight of about 800-4000;(B) an organic diisocyanate having the formula (I) ##STR1## wherein R' and R.sup.2 are hydrogen or an alkyl group having 1-5 carbon atoms, respectively, and(C) a chain extender comprising an organic diamine having the formula (II) ##STR2## wherein R' and R.sup.2 are hydrogen or 40-95 mole % alkyl group having 1-5 carbon atoms, respectively, and a phthalic acid dihydrazide having the formula (III) ##STR3## This composite sheet material is useful as a synthetic leather, especially as a suede-like leather sheet material, and has high density, good flexiblity and crease resistance, a supple touch and 60-5 mole % pertinent rubber-like repulsive elasticity.
摘要:
An intake manifold for a multi-cylinder internal combustion engine contains main intake passages leading from a main distribution chamber for supplying lean mixture to each cylinder. The intake manifold also has auxiliary intake passages leading from an auxiliary distribution chamber for supplying a rich mixture to each cylinder. Engine coolant is circulated through the intake manifold to act as heating means for the rich mixture and for part of the lean mixture. Another part of the lean mixture is not heated.
摘要:
In welding apparatus of the type comprising a pair of opposed pressing boards, and a heated platen inserted into and retracted from a space between the pressing boards and the surfaces of the articles to be welded together are fused by the heated platen and then welded together by applying a pressure to the articles, there are provided holding mechanisms for holding the article at the opposing surfaces of the pressing boards and a spacer for defining predetermined gaps between the heated platen and the pressing boards.
摘要:
Unequal fuel concentrations in air-fuel mixtures delivered by a downdraft carburetor to branched intake pipes leading to engine cylinders has been traced to asymmetrical fuel delivery into the venturi passage in the carburetor. To equalize the fuel concentrations carried in the branched pipes, an inclined wall is provided in the distribution chamber that receives the air-fuel mixture from the carburetor. The inclination of the wall directs a greater quantity of air-fuel mixture into the branched pipe which would otherwise receive a leaner mixture because of the asymmetrical distribution of fuel from the venturi passage.