摘要:
A method of producing core/shell composite nano-particles exhibiting superior characteristics, by using as cores nano-particles heat treated in advance so as to give them a specific crystal structure in a state using a barrier layer to prevent sintering and forming shells on their surface, which eliminates hindrances to the shell forming reaction due to the phase transfer catalyst or other strongly sticky dispersant, is provided. A method of producing core/shell composite nano-particles comprising nano-sized core particles covered by shells, the method comprising dispersing core particles heat treated in advance to give them a crystal structure expressing the necessary characteristics in a first organic solvent by a first dispersant to prepare a first solution, adding a polar solvent to peel off the first dispersant from the core particles and making the nano-particles agglomerate to recover them, making the recovered core particles disperse in a second organic solvent by a second dispersant to form a second solution, and adding a precursor of the shells to the second solution and forming shells on the surfaces of the core particles.
摘要:
The present invention is directed to provide a water treatment technology able to perform advanced purification treatment by efficiently removing synthetic organic compounds such as surface activators for use in cleaners and agricultural chemicals present in polluted water having a relatively low load of pollutants such as BOD. In order to accomplish this objective, water to be treated is brought in contact with a assimilable filter medium under aerobic conditions, said assimilable filter medium being composed by adhering a material to be assimilated that has specific assimilability for the target microorganisms to a porous base material such as charcoal. As a result of using this type of assimilable filter medium, specific microorganisms which are highly efficient for removing the synthetic organic pollutants to be removed can be utilized selectively, thereby enabling efficient removal of synthetic organic compounds.
摘要:
A radiation curable resin having at least two (meth)acryloyl groups at both terminal ends of a molecular chain which is obtained by reaction of (1) a polyester polyol and/or polycarbonate polyol, (2) a diisocyanate, (3) a polyfunctional (meth)acrylate containing a hydroxyl group therein, and optionally (4) a compound having at least two active hydrogens in the molecule is disclosed. The resin has at least two (meth)acryloyl groups at a terminal end of the molecular chain. The molecular weight of the resin is 1,000 to 50,000, the urethane bonding concentration is not more than 3,000 equivalent/10.sup.6 g and the (meth)acryloyl group concentration is 100 to 6,000 equivalent/10.sup.6 g. A radiation curable resin composition containing the resin and a precoated metal using the composition are also disclosed.
摘要:
A FePt alloy nanoparticle, which is expected to be a promising material used for an ultra-high-density magnetic recording medium of the next generation, is ordered by heat treatment to have high magnetic anisotropy, but there has been a problem that the particles are coalesced with each other and agglomerate during the heat treatment. According to the present invention, each particle of the alloy nanoparticles is covered with a coating such as SiO2, and thereafter a heat treatment for ordering is carried out. In this method, the alloy nanoparticles do not coalesce with each other even if the heat treatment is performed at such a high temperature as to allow all the particles to be fully ordered. After the heat treatment, only the coating is removed using an acid or alkali solution so that it is possible to obtain ordered alloy phase nanoparticles which are ordered and dispersible in various solutions. It is also possible to easily manufacture an ultra-high-density magnetic recording medium by coating surfaces of a substrate with a binder solution in which the particles are dispersed while applying a magnetic field in a predetermined direction.
摘要:
Preparations are made of a characteristic curve of conductivity showing the relationship between sodium concentration in alcohol and conductivity of alcohol as observed at a predetermined temperature and a temperature correction curve showing the change in conductivity per unit degree centigrade of alcohol temperature versus; sodium concentration in alcohol; the corrected conductivity of a sample alcohol is determined by measuring the conductivity and temperature of the sample alcohol simultaneously and subjecting the measured conductivity to temperature correction according to the above temperature correction curve; and then the sodium concentration in the sample alcohol is determined on the basis of the corrected conductivity thus obtained. Thus, the change in sodium concentration in alcohol can be measured and monitored continuously and accurately.
摘要:
A radiation curable resin which is a polyurethane acrylate having (meth)acryloyloxy groups at the terminal end of the molecule and in the molecular chain thereof, and containing metal sulfonate groups in the molecule in a ratio of 3.0 to 1,500 equivalent/10.sup.6 g of the resin, said polyurethane acrylate being obtained by reaction of(1) a copolyester having hydroxyl groups at both terminal ends of the molecule and containing metal sulfonate groups therein,(2) a diisocyanate,(3) a compound (A) having at least one (meth)acryloyloxy group and two hydroxyl groups,(4) a compound (B) having at least one (meth)acryloyloxy group and one hydroxyl group, and optionally(5) a polyol other than the above (1) or (3). the radiation curable resin containing a compound (C) having at least one carboxylic acid group and two hydroxyl groups in addition to the above components (1) to (5) is also disclosed.
摘要:
The commutating-type thyristor inverter in a static Scherbius device including a wound induction motor is protected against damage upon the occurrence of an emergency condition, in the form of a failure or reduction of the power voltage, by shifting the commutation angle of the inverter to a minimum value and reducing the inverter current to zero, and then interrupting the supply of commutating pulses to the inverter thyristors, whereby the inverter stops operating. After the emergency condition is removed, the commutating angle of the inverter is gradually increased to its normal value to restore the inverter to normal operation. If during the emergency condition the motor speed falls below a predetermined value, then the motor is accelerated through a starting resistance to a speed above this value before normal operation of the inverter is resumed.