摘要:
Self-adhesive carbonaceous grains for use in the production of high density carbon artifacts and high performance carbon-carbon composites are made by processes such as oxidation and heat treatment of specific mesophase pitches. The present carbonaceous grains exhibit excellent binding properties, shape stability when molded, and high density with higher carbonization yield, providing very high strength artifacts when their properties fall within the specific range of properties defined by their H/C and O/C values. High density carbon artifacts can be easily obtained by molding the grains and carbonizing or graphitizing the same.
摘要:
Self-adhesive carbonaceous grains for use in the manufacture of high-density and high-strength carbon artifacts containing 0.5-1.5 wt % of a quinoline-soluble but pyridine-insoluble component and at least 97 wt % of a quinoline-insoluble component and which are prepared by heat-treating in a nonoxidizing atmosphere a mesophase pitch that is obtained by polymerizing condensed polycyclic hydrocarbons or substances containing them in the presence of a superacid consisting of hydrogen fluoride and boron trifluoride. The carbonaceous grains are molded and the mold is baked at a sufficient temperature to achieve its carbonization, with the heating rate being not more than 20.degree. C./h in the temperature range from 400 .degree. to 600.degree. C. In this way, high-density and high-strength carbon artifacts showing a homogeneous fine mosaic texture of optical anisotropy can be efficiently manufactured in high carbon yield.
摘要:
Self-adhesive carbonaceous grains for use in the manufacture of high-density and high-strength carbon artifacts containing 0.5-1.5 wt % of a quinoline-soluble but pyridine-insoluble component and at least 97 wt % of a quinoline-insoluble component and which are prepared by heat-treating in a nonoxidizing atmosphere a mesophase pitch that is obtained by polymerizing condensed polycyclic hydrocarbons or substances containing them in the presence of a superacid consisting of hydrogen fluoride and boron trifluoride. The carbonaceous grains are molded and the mold is baked at a sufficient temperature to achieve its carbonization, with the heating rate being not more than 20.degree. C./h in the temperature range from 400.degree. to 600.degree. C. In this way, high-density and high-strength carbon artifacts showing a homogeneous fine mosaic texture of optical anisotropy can be efficiently manufactured in high carbon yield.
摘要:
A process for producing a friction material under low-temperature conditions using, as a reinforcement, one or more fibers selected from a metal fiber, an organic fiber and an inorganic fiber and, as a binder, a compounded pitch that consists of a mesophase pitch and sulfur and/or an aromatic nitro compound. The content of an optically anisotropic phase in the mesophase pitch is at least 80% and the softening point of the mesophase pitch is not higher than 270.degree. C. The friction material produced exhibits consistent friction characteristics over a broad temperature range.
摘要:
The improved composition for use in the production of composite carbon materials comprises a mesophase pitch containing at least 80% of an optical anisotropic phase and having a softening point of no higher than 250.degree. C., and sulfur present in an amount of 6-35 parts by weight per 100 parts by weight of said mesophase pitch. Said composition may be heated together with an aggregate and subsequently shaped to yield a composite carbon material. The improved process for producing a composite carbon material comprises impregnating an aggregate with said composition as it is melted, shaping the mixture in a temperature range of 150.degree.-350.degree. C, and then carbonizing the shaped part.
摘要:
The present invention relates to novel crystal forms of 4-{[4-({[4-(2,2,2-trifluoroethoxy)-1,2-benzisoxazol-3-yl]oxy}methyl)piperidin-1-yl]methyl}-tetrahydro-2H-pyran-4-carboxylic acid. More particularly, the invention relates to polymorph forms (Polymorph Form I or Polymorph Form II), and to processes for the preparation of, compositions containing and to uses of, such polymorph forms.
摘要:
Provided is a portable terminal equipment which can prevent operation keys from being increased and which is capable of reducing the numbers of pushing the operation keys down at the time of input of characters. The portable terminal equipment has a plurality of operation keys (10˜21) to which characters and functions are assigned are provided in an operation section to be capable of being pushed down, being released from being pushed down, and sliding, a touch sensor section (5) which detects each of the operation keys being pushed down and being released from being pushed down, a moving sensor (2) which detects the operation key sliding, and a control section (101) which executes a function assigned to the operation key, when the touch sensor section (5) detects the operation key being pushed down and then detects the operation key being released from being pushed down, and which makes a character assigned to the pushed down operation key be displayed in a display section (3), when the moving sensor (2) detects the operation key sliding while the touch sensor section (5) is detecting the operation key being pushed down.
摘要:
The present invention relates to a dielectric ceramic composition comprising a main component expressed by a general formula: (Ba1-x-ySrxCay)m(Ti1-zZrz)O3, a first subcomponent comprising Mg oxide, a second subcomponent comprising at least one kind of oxide selected from oxides of Mn and Cr, a third subcomponent comprising R oxide (note R is selected at least one kind from Y, La Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho and Yb), and a fourth subcomponent comprising an oxide including Si.
摘要:
A gas sensor is disclosed which attains high response speed, low power consumption, superior water splash resistance and a little setting direction dependency and setting angle dependency. In this gas sensor, a measured gas room is provided inside an inner cover, and gas passage holes for leading a measured gas in are provided on side surfaces of the inner cover and an outer cover. The gas passage holes provided on the outer cover are positioned much closer to a top end side than the gas passage hole provided closest to the top end side in the inner cover. Partitions disposed extendedly in an axial direction of the gas sensor are provided between the outer cover and the inner cover.
摘要:
A dielectric ceramic composition comprising BamTiO2+m (note that “m” satisfies 0.99≦m≦1.01) and BanZrO2+n (note that “n” satisfies 0.99≦n≦1.01), an oxide of Mg, an oxide of R (note that R is at least one selected from Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu), an oxide of at least one element selected from Mn, Cr, Co and Fe, and an oxide of at least one element selected from Si, Li, Al, Ge and B. With respect to 100 moles of said BamTiO2+m, 35 to 65 moles of BanZrO2+n, 4 to 12 moles of an oxide of Mg, 4 to 15 moles of an oxide of R, 0.5 to 3 moles of an oxide of Mn, Cr, Co and Fe, and 3 to 9 moles of an oxide of Si, Li, Al, Ge and B are included therein.