Abstract:
(1) A hexagonal boron nitride polycrystal comprising microcrystals on the order of nanometer; (2) a hexagonal boron nitride having an average particle diameter of 20 to 200 nm and a particle size distribution such that at least 80 % by weight of the particles have diameters falling within the average particle diameter +/- 30 %; and (3) a fine hexagonal boron nitride powder which has an ellipsoidal or discoidal form and satisfies requirements represented by the following formulae: 50 nm
Abstract:
A process for producing 3-norcephem compounds represented by general formula (2) characterized by reacting a halogenated beta -lactam compound represented by general formula (1) with a hydride reagent in the presence of a monovalent copper compound, wherein R1 represents hydrogen or optionally protected amino; R2 represents optionally substituted aryl; n is 0 to 2; R3 represents hydrogen or a carboxylate-protective group; X represents halogeno; and Y represents halogeno or a leaving group; in formula (2) R1 and R3 are each as defined above.
Abstract:
Indole-2-carboxylic ester derivatives exhibiting high bacteriocidal effects selectively on chemical-tolerant bacteria and represented by general formula (I), wherein R is hydrogen, hydroxyl, C1-C4 acyl, C1-C4 acyloxy, C1-C4 alkoxy, (C1-C4 alkoxycarbonyl)oxy, phenoxycarbonyl or C1-C4 alkoxycarbonyl; R is C1-C4 alkyl; R is hydrogen, C1-C4 alkyl, C2-C4 alkenyl, phenyl, cyano, carbamoyl or the like; R and R are each independently C1-C4 alkyl or halogen.
Abstract:
A process for the preparation of an allenyl- beta -lactam compound which comprises reacting the hydroxyl group of a beta -lactam compound of general formula (1) with a reactive functional derivative of a sulfonic acid of the general formula (2): R -SO2-X to form a beta -lactam compound of general formula (3) and reacting the formed compound with a basic anion-exchange resin containing a tertiary organic base immobilized thereon to attain the preparation of an allenyl- beta -lactam compound of general formula (4) and the stable isolation thereof from the reaction mixture in a high yield at a high purity. Another process for the preparation of an allenyl- beta -lactam compound which comprises reacting the hydroxyl group of a beta -lactam compound of general formula (1) with a reactive functional derivative of a sulfonic acid of the general formula (2): R -SO2-X to form a beta -lactam compound of general formula (3), reacting the formed compound with a tertiary organic base to form an allenyl- beta -lactam compound of general formula (4) and treating the resulting reaction mixture with both an acidic cation-exchange resin and a basic anion-exchange resin either alternately or simultaneously to isolate the compound of general formula (4) from the reaction mixture stably. A process of preparing a 3-halocephem derivative of general formula (6) by reacting an allenyl- beta -lactam compound of general formula (4) with a halogenating agent in the presence of a sulfinate or thiolate ion scavenger.
Abstract:
A process for the production of a halogenated beta -lactam compound represented by general formula (2) which comprises replacing the hydroxyl group of a halogenated beta -lactam compound represented by general formula (1) with a halogen atom or a leaving group. Another process for the production of an exomethylene penam compound represented by general formula (5) which comprises reducing a halogenated beta -lactam compound represented by general formula (2) with at least the equimolar amount of a metal having a standard oxidation-reduction potential of -0.3 (V/SCE) or below and 0.0001 to 10 times by mol as much a metal compound having a standard oxidation-reduction potential higher than that of the former metal, or employing the electrolytic reduction method.
Abstract:
A novel compound suitable for use as a photochromic material. It is a salt of a spiropyran compound represented by general formula (1), with an acid compound, wherein R represents C1-C20 alkyl, aralkyl, hydroxyethyl, acryloxyethyl or methacryloxyethyl; R to R represent each hydrogen, C1-C6 alkyl, etc.; R represents hydrogen, vinyl, -CH2OR or -CH2OCOC(R )=CH2; R represents hydrogen or C1-C4 alkyl; R represents hydrogen or methyl; and X represents oxygen or sulfur.
Abstract translation:适用于光致变色材料的新型化合物。 它是由通式(1)表示的螺吡喃化合物的盐与酸化合物,其中R 1表示C 1 -C 20烷基,芳烷基,羟乙基,丙烯酰氧基乙基或甲基丙烯酰氧基乙基; R 2至R 7表示每个氢,C 1 -C 6烷基等; R 8表示氢,乙烯基,-CH 2 OR 9或-CH 2 OCOC(R 10)= CH 2; R 9表示氢或C 1 -C 4烷基; R 10表示氢或甲基; X表示氧或硫。
Abstract:
The present invention relates to a resin composition for a mold, a mold constructed by using the composition and a molding method using the mold. This resin composition comprises a thermoplastic resin, an inorganic fibrous reinforcing material and an inorganic particulate filler, and has a bending strength of 1000 kgf/cm or higher, a modulus of elasticity in bending of 70000 kgf/cm or higher, and it can be cut and worked. The heat deformation temperature of the composition may be higher than 180 DEG C. With this composition it is possible to provide a core or a cavity in a mold which is cut and finished with a good dimensional precision, at low cost and in a short period and is durable and recyclable. The mold can be applied to various types of molding methods using various types of materials and when so used it can provide molded products with good precision and at low costs.
Abstract translation:本发明涉及一种模具用树脂组合物,使用该组合物构成的模具和使用该模具的成型方法。 该树脂组合物包含热塑性树脂,无机纤维增强材料和无机颗粒填料,弯曲强度为1000kgf / cm 2以上,弯曲弹性模量为70000kgf / cm 2或 更高,可以削减和工作。 组合物的热变形温度可以高于180℃。通过该组合物,可以在模具中提供芯或空腔,其以低成本和短时间以良好的尺寸精度进行切割和精加工 并且是耐用和可回收的。 该模具可以应用于使用各种类型的材料的各种成型方法,并且当这样使用时,其可以以高成本提供高精度和低成本的模制产品。
Abstract:
A process for producing a 3-substituted cephem compound from an allenyl- beta -lactam compound which can readily be prepared from an inexpensive penicillin compound in a short reaction path. The process comprises reacting an allenyl- beta -lactam compound with an organohalogen compound in the presence of an at least equimolar amount of a metal having a standard oxidation-reduction potential of -0.3 V/SCE or less and 0.0001 - 0.5 mol, per mole of the lactam, of a metallic compound having a standard oxidation-reduction potential higher than that of the above metal.
Abstract:
A remedy for cystic fibrosis which contains as an active ingredient alginate lyase which is produced by a strain belonging to the genus Pseudomonas and can decompose alginic acid.
Abstract:
A gas generating agent for air bags which consists of a nitrogen-containing organic compound and an oxohalogenate, has a high impact ignitability, a high combustion rate and a high gas generation rate, and can attain a comparatively low combustion temperature.