摘要:
A vinyl monomer is graft polymerized on an aromatic hydrocarbon-based polymer film substrate to introduce graft chains into the substrate and thereafter a functional monomer represented by the following formula and having sulfonic acid groups or functional groups capable of conversion to sulfonic acid groups is graft polymerized to introduce the sulfonic acid groups or the functional groups capable of conversion to sulfonic acid groups: where R is an aromatic ring or an aliphatic chain; X is (1) —OH, (2) —OLi, —ONa or —OK, (3) —F or —Cl, or (4) —OCnH2n+1 where n is an integer of 1 to 7. Since the graft chains obtained by graft polymerization of the vinyl monomer can also be utilized as scaffold polymers, the graft polymerizability of the functional monomer to the aromatic hydrocarbon-based polymer film substrate is sufficiently improved to enable the preparation of a polymer electrolyte membrane that excels not only in proton conductivity and mechanical strength but also in dimensional stability.
摘要:
Polymer ion-exchange membranes having outstanding electrical conductivity, water retention and oxidation resistance are produced by the steps of uniformly mixing an organic high-molecular weight resin with functional inorganics having the abilities to promote graft polymerization of polymerizable monomers, adsorb water and conduct protons, irradiating the resulting functional inorganics/polymer membrane to initiate graft polymerization or graft copolymerization of polymerizable monomers having functional groups, and then introducing sulfonic acid groups into the graft chains.
摘要:
A polymer film substrate is irradiated with ions to make a large number of nano-sized through-holes and the substrate may be further irradiated with ionizing radiation so that a functional monomer may be grafted or co-grafted onto a surface of the film and within the holes; in addition, sulfonic acid group(s) may be introduced into the graft chains to produce a polymer ion-exchange membrane that may have high oxidation resistance, dimensional stability, electrical conductivity and/or methanol resistance, as well as may have an ion-exchange capacity controlled over a wide range.
摘要:
A honeycomb structure having a crystal phase composed of aluminum titanate and mullite, which is obtained by sintering a honeycomb molding made of a mixture comprising titania powder, alumina powder, silica powder and mullite powder, the mixture containing 1-10 parts by mass of silica powder and 5-30 parts by mass of mullite powder per the total amount (100 parts by mass) of the titania powder and the alumina powder, and the mullite powder containing 40-60% by mass of particles having particle sizes of 10-50 μm and 5-30% by mass of particles having particle sizes of 3 μm or less, and its production method.
摘要:
An aromatic polymer film substrate, or a grafted aromatic polymer film substrate having a monomer introduced therein as graft chains is irradiated with ionizing radiation to impart a crosslinked structure. The aromatic polymer film substrate or the grafted aromatic polymer film substrate, provided with the crosslinked structure, is directly sulfonated to obtain a crosslinked aromatic polymer electrolyte membrane. The crosslinked aromatic polymer electrolyte membrane has low water uptake, high proton conductivity, low methanol permeability, high chemical stability, and excellent mechanical characteristics.
摘要:
To provide a parallel ruler device with which it is easy to obtain a plate material of a constant width having parallel sides. Also, to make it possible to easily carry out a precision adjustment of an amount of parallel movement of a ruler face by means of a visual observation. Also, to enable a precision adjustment of a desired dimension in both a positive direction and a negative direction with a position fixed once as a base point. In a parallel ruler device which includes a moving body movable along a sliding portion provided on a main body, and in which the moving body has a sliding counterpart making contact with the sliding portion, and is configured in such a way that a ruler face set in a portion other than the sliding counterpart moves in parallel along with the movement of the moving body, an inclined sliding portion 12 is set in a direction intersecting a longitudinal direction of the main body 11, a direction of the ruler face 17 of the moving body is set in a direction intersecting that of the sliding counterpart 16 of the moving body 15 which slides along the inclined sliding portion, and the ruler face of the moving body is configured in such a way as to move away from or near to the main body along with the movement of the moving body.
摘要:
A clamp tool for woodwork or metalwork in which a screw mechanism is not apart away from a shaft and is not exposed is disclosed. In the clamp tool, a pair of clamping brackets is disposed on a shaft apart from each other and at least one clamping bracket is movable along the shaft to fasten a workpiece in cooperation with the other clamping bracket. Here, a female screw constituting a screw mechanism is disposed at one end of the shaft, a male screw constituting the screw mechanism is rotatable in a slide cylinder disposed outside at the end of the shaft so as to be screwed to the female screw, a handle for rotationally manipulating the male screw is disposed, and a guide portion is disposed between the shaft and the slide cylinder so that the female screw does not rotate but goes straight with the rotation of the male screw so as to allow the clamping bracket disposed outside the slide cylinder to move along the shaft.
摘要:
A polymer film substrate is irradiated with ions to make a large number of nano-sized through-holes and the substrate is further irradiated with an ionizing radiation so that a functional monomer is grafted or co-grafted onto a surface of the film and within the holes; in addition, the sulfonic acid group is introduced into the graft chains, thereby producing a polymer ion-exchange membrane that has high oxidation resistance, dimensional stability, electrical conductivity and methanol resistance, as well as an ion-exchange capacity controlled over a wide range.
摘要:
An RF coil which can restrain coupling while enhancing the freedom of design and arrangement of coils is to be provided. The RF coil unit of a magnetic resonance imaging apparatus is provided with a central coil surrounding a subject around its body axis, an auxiliary coil disposed toward one end of the central coil and having first loop units mutually opposed with the body axis in-between, and another auxiliary coil disposed toward the other end of the central coil and having second loop units mutually opposed with the body axis in-between, wherein one of the first loop unit and one of the second loop unit are arranged to be on mutually reverse sides with respect to the body axis and so connected that the directions of currents resulting from increases in magnetic fluxes in the same direction are in mutually reverse directions.
摘要:
Influence of drift of a metal band in a band saw is corrected, so that an intended shape can be easily cut out. In a band saw of cutting a workpiece using a flexible metal band, an auxiliary device used in cutting the workpiece includes a body that is disposed on a surface of a work table of the band saw, and has a passage portion of the metal band at one end; a correction mechanism interposed between the body and the work table to shift a direction of the body in a direction deviated from a virtual cutting line by the metal band to correct deviation of a cutting direction by the metal band; and a clamp unit for clamping the body to the work table; wherein part of the body having a shifted direction is parallel to a direction of feeding the workpiece to the metal band.