摘要:
The invention provides a process for production of powder of perovskite compound which comprises: the first step for obtaining an aggregate of perovskite compound which comprises at least one A group element selected from the group consisting of Mg, Ca, Sr, Ba and Pb and at least one B group element selected from the group consisting of Ti, Zr, Hf and Sn, and which is represented by the general formula ABO3 wherein A is at least one A group element and B is at least one B group element; and the second step for heating the aggregate of perovskite compound obtained in the first step in a solvent at a temperature in a range from 30° C. to 500° C. whereby disintegrating the aggregate. The process makes it unnecessary to resort to a conventional mechanical crushing means or to make use of impact caused by milling media or airflow, but it makes possible to obtain a powder of perovskite compound which is not contaminated with impurities derived from milling media or chipping particles but has a high purity and a narrow particle size distribution.
摘要:
The invention provides a process for production of powder of perovskite compound which comprises: the first step for obtaining an aggregate of perovskite compound which comprises at least one A group element selected from the group consisting of Mg, Ca, Sr, Ba and Pb and at least one B group element selected from the group consisting of Ti, Zr, Hf and Sn, and which is represented by the general formula ABO3 wherein A is at least one A group element and B is at least one B group element; and the second step for heating the aggregate of perovskite compound obtained in the first step in a solvent at a temperature in a range from 30° C. to 500° C. whereby disintegrating the aggregate. The process makes it unnecessary to resort to a conventional mechanical crushing means or to make use of impact caused by milling media or airflow, but it makes possible to obtain a powder of perovskite compound which is not contaminated with impurities derived from milling media or chipping particles but has a high purity and a narrow particle size distribution.
摘要:
The invention provides a process for production of a composition comprising a perovskite structure compound, the process comprising: a first process to heat a hydrous oxide of at least one B group element selected from the group consisting of Ti, Zr, Hf, and Sn at a temperature within a range of 80 to 300° C. in the presence of an aqueous medium so as to dehydrate the hydrous oxide; and a second process to heat a reaction product obtained in the first process and a hydroxide of at least one A group element selected from the group consisting of Ba, Sr, Ca, Mg and Pb at a temperature within a range of 100 to 300° C. in the presence of an aqueous medium.The process provides a composition comprising an ABO3 compound in the form of uniform and fine spherical particles which have an average particle diameter of 1 μm or less, preferably within a range of 0.01 to 0.5 μm, high crystallinity, and a controlled A/B ratio as desired, as well as few internal pores in the crystalline particles.
摘要:
The invention provides a process for production of a composition comprising a perovskite structure compound, the process comprising: a first process to heat a hydrous oxide of at least one B group element selected from the group consisting of Ti, Zr, Hf, and Sn at a temperature within a range of 80 to 300° C. in the presence of an aqueous medium so as to dehydrate the hydrous oxide; and a second process to heat a reaction product obtained in the first process and a hydroxide of at least one A group element selected from the group consisting of Ba, Sr, Ca, Mg and Pb at a temperature within a range of 100 to 300° C. in the presence of an aqueous medium.The process provides a composition comprising an ABO3 compound in the form of uniform and fine spherical particles which have an average particle diameter of 1 μm or less, preferably within a range of 0.01 to 0.5 μm, high crystallinity, and a controlled A/B ratio as desired, as well as few internal pores in the crystalline particles.
摘要:
An incision device capable of preventing inadvertent firing, and including a covered attached to the device. The incision device comprises a housing, and a lancet guide assembly having lancet guides and a lancet body. The lancet body further comprises a lancet blade. The lancet blade is covered by a removable protective cover having a stopper which prevents a trigger arm from being moved so as to fire the lancet blade.
摘要:
A vibration detection system comprises a battery-less vibration sensor and an interrogator. The sensor comprises a single port surface acoustic wave resonator. The interrogator continuously transmits a carrier wave signal to the resonator while receiving a wave signal reflected from the resonator. The reflected wave signal includes components other than the transmitted carrier wave signal if the sensor senses a vibration event. Based the reflected wave signal, the interrogator judges whether the vibration event occurs.
摘要:
The present invention provides a reverse conducting (RC) thyristor of a planar-gate structure for low-and-medium power use which is relatively simple in construction because of employing a planar structure for each of thyristor and diode regions, permits simultaneous formation of the both region and have high-speed performance and a RC thyristor of a buried-gate or recessed-gate structure which has a high breakdown voltage by the use of a buried-gate or recessed-gate structure, permits simultaneous formation of thyristor and diode regions and high-speed, high current switching performance, and the RC thyristor of the planar-gate structure has a construction which comprises an SI thyristor or miniaturized GTO of a planar-gate structure in the thyristor region and an SI diode of a planar structure in the diode region, the diode region having at its cathode side a Schottky contact between n emitters or diode cathode shorted region and the thyristor region having at its anode side an SI anode shorted structure formed by p.sup.+ anode layers, wave-shaped anode layers or anode n.sup.+ layers; in the case of a high breakdown device, an n buffer layer is added; similarly the RC thyristor of the buried-gate or recessed-gate structure has a construction which comprises an SI thyristor of a buried-gate or recessed-gate structure at the thyristor region and an SI diode of the buried or recessed structure.
摘要:
A numerical control apparatus allows a portion of a prototype or the like to be easily machined without an operator being concerned with a coordinate system, origins, and other data. A guidance function executing unit displays guidance information on a display unit. According to the displayed guidance information, the operator enters machining commands using a keyboard, etc. A pulse distributing unit sends present positions from present position registers to the guidance function executing unit. The guidance function executing unit calculates a movement command from command values commanded by the operator and the present positions, and sends the calculated movement command to the pulse distributing unit, which outputs distributed pulses to drive the machine tool.
摘要:
A programmable controller according to the present invention is for reinforcing the function of a programmable machine controller (PMC) of a numerical control unit (CNC) incorporating a minicomputer. In order to achieve high-speed processing of a PMC ladder program which implements auxiliary control functions for machining inclusive of tool-change control, control of the rotational speed of a spindle and workpiece-change control, the programmable controller is provided with an electrically rewritable programmable read-only memory (EEPROM) (6), and a random-access memory (RAM) (7) to which program data is transferred from the EEPROM (6), and the arrangement is such that the contents of the EEPROM (6) are rewritten before the data transfer.
摘要:
A method for purifying a crude high-molecular weight substance containing an alkali metal compound by extracting the alkali metal compound with water is disclosed, which comprises stirring a mixture comprising said crude high-molecular weight substance and water in a high-speed stirring tank to extract the alkali metal compound into an aqueous phase and separating the high-molecular weight substance phase and the aqueous phase from each other by continuous centrifugation. An alkali metal compound as an impurity can be efficiently removed with small-sized equipment in a short time.