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91.
A magnesium enamide derived from N-2-(N′,N′-dimethylamino)ethyl imine reacts with primary and secondary alkyl chlorides and fluorides to give an α-alkylated ketone in good to excellent yields upon hydrolysis of the imine moiety. Reactions of the highly nucleophilic magnesium enamide derived from an unsymmetrical ketone take place regioselectively. In addition, the C-C bond formation is stereospecific: a substantial inversion of stereochemistry at the electrophilic carbon center (Walden inversion) was observed, proving its potential utility for the production of optically active compounds. 相似文献
92.
Electrons with an energy of 300 keV or lower were defined as “Soft-electrons”, which showed several advantages over conventional irradiation with gamma-rays or high-energy electrons in decontamination of grains and spices. Energies of electrons necessary to reduce microbial loads to levels lower than 10 CFU/g were 60 keV for brown rice, 75 keV for wheat, 100 keV for white pepper, coriander and basil, 130 keV for buckwheat, 160 keV for rough rice, and 210 keV for black pepper. Electrons with such energies did not significantly influence the quality. 相似文献
93.
Rieko Furuyama Terunori Fujita Setsuko Fujiyoshi Funaki Tadahito Nobori Takushi Nagata Kenji Fujiwara 《Catalysis Surveys from Asia》2004,8(1):61-71
This contribution reports Mitsui's R&D activities in the field of catalysis technology focusing on molecular catalysts. Examples of the high-performance molecular catalysts developed at Mitsui include bis(phenoxy-imine) group 4 transition metal complex catalysts (FI Catalysts), phosphazene catalysts (PZN catalysts) and b(beta)-ketoiminato Co(II) complex catalysts. Many of the materials stemming from these catalysts were either difficult or impossible to prepare using conventional catalysts. 相似文献
94.
Yoshihisa Kurasawa Kaoru Yamazaki Setsuko Tajima Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1986,23(3):957-958
3-Formyl-2-oxo-1,2-dihydroquinoxaline chlorophenylhydrazones 4a-c were synthesized from the reactions of 3-methyl-2-oxo-1,2-dihydroquinoxaline 3 with chlorophenyl diazonium salts, and 4b,c were found to exhibit the tautomeric equilibria between the hydrazone imine and diazenyl enamine forms in the dimethylsulfoxide solutions. 相似文献
95.
S. Shibata M. Yamane K. Kamada K. Ohta K. Sasaki H. Masuhara 《Journal of Sol-Gel Science and Technology》1997,8(1-3):959-964
Interaction between laser light and a micrometer-size spherical particle causes an optical resonance in its interior since
a spherical wall acts as a cavity. The present work seeks to investigate the preparation of organicinorganic particles containing
laser dyes and demonstrate their lasing behavior. Rhodamine 6G was incorporated into organic-inorganic spherical particles
of micrometer-size using sol-gel technique. Phenyl triethoxy silane was used as a starting material for particles. Particle
size was 1–10 μm and dye content was 1–7 × 10−5 mol/g. A particle was set on a glass plate in air and pumped by a second harmonic pulse ofQ-switched Nd-YAG laser (532 nm wavelength). From a particle of 6 μm in diameter, a strong laser emission peak was observed
at 598 nm wavelength which corresponded to the whispering-gallery mode resonance. 相似文献
96.
Kakinoki K Yamane K Igarashi M Yamamoto M Teraoka R Matsuda Y 《Chemical & pharmaceutical bulletin》2005,53(7):811-815
To characterize the photocatalytic activity of TiO2 via solid-state reaction, the relationship between the physicochemical properties and photocatalytic activity of TiO2 was investigated and estimated from the results of photodegradation of nisoldipine. The photodegradation of nisoldipine was significantly enhanced by addition of TiO2. Two degradation products, nitroso-phenylpyridine derivative and nitro-phenylpyridine derivative, were formed. The degree of photocatalytic activity of TiO2 was quite different between the various types of TiO2 investigated, even when the crystalline phase was the same. As a result of the investigations into the relationship between the photocatalytic activity and physicochemical properties of TiO2, it was found that for the rutile form the photocatalytic activity has good correlation with specific surface area of TiO2, but poor correlation with water loss on drying of TiO2. However, for the anatase form, the photocatalytic activity has good correlation with water loss on drying of TiO2, but poor correlation with specific surface area. Moreover, it was found that the crystallinity of TiO2 has a moderate correlation with the photocatalytic activity of both crystal forms of TiO2. These results suggest that a degree of photocatalytic activity of TiO2 depends on the various physicochemical properties of each type of TiO2 investigated. 相似文献
97.
Yusuke Kaminaga Takahiro Yamada Hisanori Yamane 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):i10-i12
A new quaternary compound in the Ca–Eu–Sn–O system, namely calcium europium tin heptaoxide, Ca1.5Eu3Sn0.5O7, was prepared by solid‐state reaction at 2073 K. All atoms in the structure are on 4i special positions (on mirrors) in space group C2/m. Ca/Eu sites are situated within two O octahedra and within two sevenfold coordination sites surrounded by O‐capped trigonal prisms. A Ca/Eu/Sn site is coordinated by five O atoms. The structural formula can be represented as (Ca0.28Eu0.72)(Ca0.16Eu0.84)(Ca0.46Eu0.54)(Ca0.28Eu0.72)(Ca0.32Eu0.18Sn0.50)O7. The crystal structure is a new type and is related to the structure of B‐form Eu2O3. 相似文献
98.
T. Koyama R. Hayashi T. Yamane E. Masuda A. Kurose K. Hanabusa H. Shirai T. Hayakawa N. Hojo 《Colloid and polymer science》1987,265(9):786-790
Prussian blue and its analogs bonded to poly(vinylamine hydrochloride) (PVAm · HCl) containing FeII or FeIII and M2+ (M=Fe, Co, Cu) in a 11 molar ratio were obtained by the reaction of [Fe(CN)6]
n– (n=3,4) with M2+ ion-PVAm · HCl mixture in aqueous solution. Under a limited polymer concentration (TVAm/TFe over 10), these polymer complexes thus obtained were stable and soluble in water. By casting these solutions, colored films can be produced. The formation of Prussian blue and its analogs bonded to PVAm · HCl was also investigated by the Benesi-Hildebrand method. The molar extinction coefficients of intervalence charge transfer (FeIIFeIII, CoIIFeIII, FeIICuII) band for MFe(CN)6](n–2)– bound to PVAm · HCl (M=Fe, Co, Cu) were found to be 10,100–9601 · mol–1 · cm–1 at 25 C. The formation constants were found to be in the range of 107 to 1010 M–1. The changes of enthalpy (H) and entropy (S) were found to be in the range of –10.4 to –22.5 kJ · mol–1 and 5.7 to 52.9 J · K–1 mol–1 respectively, at 25C. 相似文献
99.
Minoru Tsuda Masayuki Hata Rie Nishida Setsuko Oikawa 《Journal of polymer science. Part A, Polymer chemistry》1997,35(1):77-89
The acid-catalyzed degradation mechanism of chemical amplification resists based on end-capped poly(phthalaldehyde) has been elucidated by semi-empirical molecular orbital calculations. It is concluded that: (i) two different starting points exist in the degradation of end-capped poly(phthalaldehyde), the central part of the polymer as well as the polymer end; (ii) in both cases, after the first protonation, cationic hydroxyl compounds generated decompose to the identical cation intermediate, which can unzip itself to phthalaldehyde monomers successively (unzipping reaction); (iii) the hemiacetal type intermediates hardly degrade to the same intermediate without acid catalyst; (iv) the overall activation energy for the degradation reaction is less than 14 kcal/mol in all the cases. Thus, the poly(phthalaldehyde) resist can easily self-develop below 100°C, as reported in the literature. © 1997 John Wiley & Sons, Inc. 相似文献
100.
Daisuke Sawai Akira Yamane Hiroshi Takahashi Tetsuo Kanamoto Masayoshi Ito Roger S. Porter 《Journal of Polymer Science.Polymer Physics》1998,36(4):629-640
Ultradrawing of atactic poly(acrylonitrile) (PAN) was investigated for a Mv series, ranging 8.0 × 104–2.3 × 106. Samples for the draw were prepared from 0.5–30 wt % solutions of PAN in N,N′-dimethylformamide. The solutions were converted to a gel by quenching from 100 to 0°C. The dried gel films were initially drawn uniaxially by solid-state coextrusion (first-stage draw) to an extrusion draw ratio (EDR) of 16, followed by further tensile draw at 100–250°C (second-stage draw). The maximum total draw ratio (DRt,max) and tensile properties achieved by two-stage draw increased remarkably with sample Mv. Other factors affecting ductility were the solution concentration from which gel was made and the second-stage draw temperature. The effects of these variables became more prominent with increasing Mv. The temperature for optimum second-stage draw increased with sample Mv. Both the initial gel and the drawn products showed no small-angle X-ray long period scattering maximum, suggesting the absence of a chain-folded lamellae structure, which had been found in our previous study on the drawing of nascent PAN powder. The chain orientation function (fc) and sample density (ρs) increased rapidly with DRt in the lower range (DRt < 30) and approached constant values of fc = 0.980–0.996 and ρs = 1.177–1.181 g/cm3, respectively, at higher DRt > 30–100. The tensile modulus also showed a similar increase with DRt. The tensile strength increased linearly with DRt, reaching a maximum, and decreased slightly at yet higher DRt. The highest modulus of 28.5 GPa and strength of 1.6 GPa were achieved with the highest Mv of 2.3 × 106. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 629–640, 1998 相似文献