摘要:
A metallocene compound is provided wherein to a transition metal compound is bonded a multidentate compound wherein a substituted cycloalkadienyl ring CA1 having therein a heteroaromatic group Ra containing an oxygen, sulfur or nitrogen atom on a cycloalkadienyl ring, preferably the five-membered ring thereof, and an unsubstituted or substituted cycloalkadienyl group CA2 or —(R1)N—, —O—, —S— or —(R1)P—, preferably CA2, more preferably a substituted cycloalkadienyl group identical with CA1 are bonded through a divalent linking group. The metallocene compound is suitable as a principal ingredient of a catalyst for the polymerization of olefins, particularly achieving a very high effect in making the molecular weight of a polypropylene higher.
摘要:
A metallocene compound is provided wherein to a transition metal compound is bonded a multidentate compound wherein a substituted cycloalkadienyl ring CA1 having therein a heteroaromatic group Ra containing an oxygen, sulfur or nitrogen atom on a cycloalkadienyl ring, preferably the five-membered ring thereof, and an unsubstituted or substituted cycloalkadienyl group CA2 or —(R1)N—, —O—, —S— or —(R1)P—, preferably CA2, more preferably a substituted cycloalkadienyl group identical with CA1 are bonded through a divalent linking group. The metallocene compound is suitable as a principal ingredient of a catalyst for the polymerization of olefins, particularly achieving a very high effect in making the molecular weight of a polypropylene higher.
摘要:
Disclosed are &mgr;-oxo-bis-metallocene complex compounds, catalysts for the polymerization of olefins comprising a &mgr;-oxo-bis-metallocene complex compound and at lease one cocatalyst selected from the group consisting of an aluminoxane, an ionic compound, and a Lewis acid, and a process for the polymerization of olefins. An example of the &mgr;-oxo-bis-metallocene complex compound is represented by the following formula (1): wherein, for example, M is zirconium, n is 1, Y is silicon, X is chloro, and R1-R10 maybe hydrogen or alkyl.
摘要:
Disclosed is a process for the preparation of metallocone complexes wherein stereoisomers of metallocene complexes formed at the time of synthesis can easily be separated. The gist of the present invention resides in separation of a part of an isomeric mixture of specific metallocene complexes bridged with a transition metal represented by the formula (1) as a complex having M—O bond. In particular, preferable is a process for separating a part of an isomeric mixture of a metallocene complex represented by the formula (2) as a &mgr;-oxo-complex represented by the formula (3).
摘要:
An IGBT has an emitter region, a top body region that is formed below the emitter region, a floating region that is formed below the top body region, a bottom body region that is formed below the floating region, a trench, a gate insulating film that covers an inner face of the trench, and a gate electrode that is arranged inside the trench. When a distribution of a concentration of p-type impurities in the top body region and the floating region, which are located below the emitter region, is viewed along a thickness direction of a semiconductor substrate, the concentration of the p-type impurities decreases as a downward distance increases from an upper end of the top body region that is located below the emitter region, and assumes a local minimum value at a predetermined depth in the floating region.
摘要:
A liquid sealed vibration isolating device has an elastically movable diaphragm capable of preventing elastic deformation of a relief valve to realize high damping while preventing a cavitation phenomenon. The relief valve is provided in the elastic movable diaphragm arranged in a partition member in order to open and close a leak passage so as to prevent occurrence of the cavitation phenomenon. The relief valve is integrally formed with a fixing portion of the elastic movable diaphragm. There is provided an upwardly open concavity that the relief valve faces. The relief valve is made thicker and provided with an opening and closing adjustment groove at a basal portion of its inclined wall. The opening and closing adjustment groove is formed with a locally thin bending portion functioning as a starting point of bending in an opening and closing operation of the relief valve.
摘要:
A specific information input region (B) individually specifying information to be input and an input mode switching region (C) used for changing an information input mode are placed on an information input region (A) set on a substrate. Each of these regions is displayed to be visible. An optical sensor detects a touched position on the information input region. Then, the touch operation in the input mode switching region (C) is detected according to the output of the optical sensor to selectively switch the information input mode among keyboard input, pen tablet input and mouse input. The output of the optical sensor is analyzed according to the set input mode to find out the information input by the touch operation.
摘要:
In a reverse conducting semiconductor device, which forms a composition circuit, a positive voltage that is higher than a positive voltage of a collector electrode may be applied to an emitter electrode. In this case, in a region of the reverse conducting semiconductor device in which a return diode is formed, a body contact region functions as an anode, a drift contact region functions as a cathode, and current flows from the anode to the cathode. When a voltage having a lower electric potential than the collector electrode is applied to the trench gate electrode at that time, p-type carriers are generated within the cathode and a quantity of carriers increases within the return diode. As a result, a forward voltage drop of the return diode lowers, and constant loss of electric power can be reduced. Electric power loss can be reduced in a power supply device that uses such a composition circuit in which a switching element and the return diode are connected in reverse parallel.
摘要:
A protrusion (13a) and a protrusion (13b) are formed a predetermined distance apart in the direction of a shaft in the outer circumferential surface of the roller main body (11). The cross sections of the protrusion (13a) and the protrusion (13b) are shaped such that a center portion of the roller main body (11) in the direction of the shaft is a boundary (14), and that on the left side of the boundary (14), a vertex (131a) is displaced to the left side from the perpendicular bisector (133a) of an opposite side (132a) whereas on the right side of the boundary (14), a vertex (131b) is displaced to the right side from the perpendicular bisector (133b) of an opposite side (132b). In this way, in a metallic movement roller that moves a strung endless belt, the winding movement and the like of the belt can be prevented, and the belt can be intentionally moved in a specific direction.
摘要:
A partition member is provided with an elastic body for absorbing hydraulic pressure fluctuation of the primary liquid chamber and a frame member for supporting an outer circumferential portion of the elastic body while aiming to prevent the rotation of the elastic body. A relief aperture communicating between the primary liquid chamber and the secondary liquid chamber is located on the outer circumferential side in the elastic body supporting region of the frame member. A relief valve for opening and closing the relief aperture is integrally formed on the outer circumferential side of the elastic body. The relief valve is formed of a pair of right and left relief valves. A width across flat sections are formed on a thick-walled outer circumferential section of the elastic body which is located between the right and left relief valves, such as to serve as a detent means.