摘要:
A method for producing a hydroxypyrazine derivative represented by formula (I) (wherein R1 represents a halogen atom), the method including reacting a pyrazine derivative represented by formula (III) (wherein R2 represents a nitrile group, an N-unsubstituted or N-substituted carbamoyl group, an ester group or a carboxyl group, M represents a cation capable of forming a salt, and n represents a number corresponding with the valence of M) with a halogenating agent. Also, a method for producing a dichloropyrazine derivative represented by formula (II) (wherein R21 represents a nitrile group, an N-unsubstituted or N-substituted carbamoyl group, an ester group, a carboxyl group, or a group formed as a result of a change in the functional group of R2 during chlorination), the method including reacting the hydroxypyrazine derivative (I) with a chlorinating agent.
摘要:
A method for producing a hydroxypyrazine derivative represented by formula (I) (wherein R1 represents a halogen atom), the method including reacting a pyrazine derivative represented by formula (III) (wherein R2 represents a nitrile group, an N-unsubstituted or N-substituted carbamoyl group, an ester group or a carboxyl group, M represents a cation capable of forming a salt, and n represents a number corresponding with the valence of M) with a halogenating agent. Also, a method for producing a dichloropyrazine derivative represented by formula (II) (wherein R21 represents a nitrile group, an N-unsubstituted or N-substituted carbamoyl group, an ester group, a carboxyl group, or a group formed as a result of a change in the functional group of R2 during chlorination), the method including reacting the hydroxypyrazine derivative (I) with a chlorinating agent. According to the present invention, a dichloropyrazine derivative can be produced efficiently at low cost, and a hydroxypyrazine derivative that functions as a production intermediate for the dichloropyrazine derivative can be produced efficiently at low cost.
摘要:
A method for producing a hydroxypyrazine derivative represented by formula (I) (wherein R1 represents a halogen atom), the method including reacting a pyrazine derivative represented by formula (III) (wherein R2 represents a nitrile group, an N-unsubstituted or N-substituted carbamoyl group, an ester group or a carboxyl group, M represents a cation capable of forming a salt, and n represents a number corresponding with the valence of M) with a halogenating agent. According to the present invention, a hydroxypyrazine derivative that functions as a production intermediate for the dichloropyrazine derivative can be produced efficiently at low cost.
摘要:
In a mounting structure of a key lock unit comprising a key lock unit having a locking rod whose end engages and disengages with a lock recess portion formed in a steering shaft in a column tube, and a rod housing which slidably provides the locking rod therein, a boss portion provided on the end of the rod housing being fitted into a penetrating mounting hole of the column tube, and a key lock bracket that receives and supports the end of the key lock unit being welded to the column tube, according to the present invention, a patch bracket having a through hole with a size corresponding to the mounting hole, and disposed in overlap with the outer surface of the column tube, matching the through hole with the mounting hole, and further welded to the key lock bracket, is provided, a through hole-shaped gap is provided between the key lock bracket and the column tube, and a detecting protrusion which fits into the through hole-shaped gap is provided.
摘要:
A power steering device for a motor vehicle whereby when the vehicle is under a high or middle speed movement, the slide torque is controlled to a relatively low constant level irrespective of the turning of the steering wheel. The device includes a hydraulic pump for producing a hydraulic pressure; a power cylinder powered by the hydraulic pressure for producing a force to assist the steering job; a hydraulic valve for controlling the hydraulic pressure supplied to the power cylinder, the hydraulic valve including a valve shaft and a valve body; a chattering protection seal associated with the hydraulic valve to assure a concentric rotation of the valve shaft relative to the valve body with an assistance of hydraulic pressure applied thereto; and an electronically controlled solenoid valve. The electronically controlled solenoid valve applies when the vehicle is at a standstill or under a low speed movement, the chattering protection seal with a hydraulic pressure which is varied as a steering wheel is turned, and applies, when the vehicle is under a high or middle speed movement, the chattering protection seal with a hydraulic pressure which is controlled to a relatively low constant level even when the steering wheel is turned.
摘要:
A method and an apparatus for manufacturing a fluoride glass fiber preform are disclosed which preclude the step of pouring a glass melt into a mold from a crucible, and hence permit the fabrication of a long, homogeneous fluoride glass fiber preform free from foreign substances and air bubbles leading to scattering and which also allow ease in the fabrication of a preform having an elliptic core portion for drawing a polarized wave retaining fiber.
摘要:
A light amplifying apparatus adopting a redundant structure. Optical isolators 13, 14 are inserted between pump light sources 1, 2 and a photocoupler 4 so as to prevent injection locking, thereby preventing fluctuation of pump power.In another embodiment, optical fibers 15 adequately longer than the coherence length of the excitation light waves output from the pump light sources are provided. In still another embodiment, the frequency of the driving current for the pump light sources is modulated. In a further embodiment, wave plates 20, 21 are provided so as to circularly polarize the light waves output from the pump light sources clockwise and counterclockwise.
摘要:
The process of manufacturing an oil cooler which comprises the steps of:(A) making cooling fins by forming a plurality of insertion holes of which inner brim is projected along the axial direction for inserting a plurality of tubes in each sheet to be transformed into cooling fins, and to drill a plurality of pores for inserting linear brazing materials at positions closed to the insertion holes, respectively,(B) inserting a plurality of tubes arranged in parallel into each of insertion holes of a number of the cooling fins respectively, and inserting linear brazing materials into the pores of each of the cooling fins, and(C) joining the brims of the cooling fins and the tubes by heating to melt said brazing materials.
摘要:
A shift lever device which includes: a shift lever turnably fitted on a stationary member; an engaging member for engagement of the shift lever with the stationary member; and a knob fitted on the shift lever. The engaging member is moved toward its distal end to disengage from the stationary member. The knob includes a knob body provided with a fitting hole into which the shift lever is inserted together with a first engaging part of the engaging member, a button pivoted on the knob body, and a link lever connected to the button, having a second engaging part for engagement with the first engaging part. When the shift lever is inserted into the fitting hole and the distal end thereof reaches a predetermined position therein, the button is operated to have the second engaging part engaged with the first engaging part.
摘要:
A shift lever device which includes: a shift lever turnably fitted on a stationary member; an engaging member for engagement of the shift lever with the stationary member; and a knob fitted on the shift lever. The engaging member is moved toward its distal end to disengage from the stationary member. The knob includes a knob body provided with a fitting hole into which the shift lever is inserted together with a first engaging part of the engaging member, a button pivoted on the knob body, and a link lever connected to the button, having a second engaging part for engagement with the first engaging part. When the shift lever is inserted into the fitting hole and the distal end thereof reaches a predetermined position therein, the button is operated to have the second engaging part engaged with the first engaging part.