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71.
本文提供了一种测定火炸药冲击感度,并根据测定值判定其冲击爆炸危险性的新方法测定水下爆炸气泡能法。通过对30几种炸药的试用,判定的结果与文献报道的用其他方法判定的结果相当好的一致。而且本法的优点还在于同时可得到试样的动、静态威力,操作简便、安全、噪音小。此外,利用本试验法还探讨了炸药形态、惰性介质(水)对冲击感度的影响。这些对于处理炸药时应如何采取安全对策具有指导意义。 相似文献
72.
Yoshida Keiichiro Ishizuka Tomohiro Mizushima Chiharu Nishidate Izumi Kawauchi Satoko Sato Shunichi Sato Manabu 《Optical Review》2015,22(2):374-384
Optical Review - To evaluate multi-spectral images of the absorption and scattering properties in the cerebral cortex of rat brain, we investigated spectral reflectance images estimated by the... 相似文献
73.
Unsaturated nitriles have been synthesized from trisubstituted olefins via ene-type chlorination and regioselective substitution with cyanide ion followed by double bond migration. 相似文献
74.
Abstract The epoxidation of allylic alcohols with H2O2 catalyzed by a new Mo-species, [PMo12O40]3?[C5H5N+(CH2)15CH3]3 (MPCP), prepared from 12-molybdatophosphoric acid (H3PMo12O40) and cetylpyridinium chloride [C5H5N+(CH2)15CH3 · Cl?], has recently rep0rted.) The high regioselectivity for the epoxidation by this MPCP-H2O2 system was comparable to that of Sharpless method using t-BuOOH as oxidant. 相似文献
75.
Katsuya Maeyama Kenji Yamashita Shugo Maeda Noriyuki Yonezawa Shunichi Aikawa Yasuhiko Yoshida 《合成通讯》2013,43(23):4158-4170
Optically active aromatic ether ketone macrocycles containing 2,2′-dimethoxy-1,1′-binaphthyl-6,6′-diyl moieties were synthesized through electrophilic aromatic substitution reaction and stepwise nucleophilic aromatic substitution reactions. Structures of the resulting macrocycles were confirmed by NMR and matrix assisted laser desorption/ionization time of flight (MALDI-TOF) mass measurements. 相似文献
76.
Molydbenum and tungsten-catalyzed oxidations of alcohols with dilute hydrogen peroxide under phase-transfer conditions have been focused in recent years 1–3. In a previous paper, we have reported that tricetylpyridinium-12-molybdophosphate(CMP), [π - C5H5N+(CH2 15CH3]3 (PMO12O40)3-, prepared from 12-molybdophosphoric acid (MPA) and cetylpyridinium chloride (CPC), catalyzed the oxidation of secondary alcohols to carbonyl compounds with tert-butylhydroperoxide(t-BuOOH)4. When hydrogen peroxide in place of t-BuOOH was employed as the oxidant for the above oxidation, however, alcohols were oxidized with difficulty to give carbonyl compounds in poor yields. In continuation of this study, we wish to report here the selective oxidation of secondary hydroxy group of alcohols and diols and diols with H2O2 under the influence to tricetylpyridinium-12 tungstophosphate (CWP), [π-C5H5N+ (CH2) 15 CH3]3(PW12O40)3-, derived from 12-tungstophosporic acid (WPA) and CPC. 相似文献
77.
Mari Iizuka Shoju Fukushima Yuki Goto Masaaki Okazaki Hideo Sawada Masato Yoshida 《Colloid and polymer science》2013,291(3):595-601
Head-to-head-type styrene and substituted styrene dimers bearing two fluoroalkyl end-groups have been efficiently synthesized by a simple reaction of perfluoroalkyl iodide with styrene under radical conditions as a mixture of meso and racemic forms. The meso form obtained from the mixture by recrystallization gave a crystal suitable for X-ray diffraction study and the crystal structure was found to be based on π-stacking of benzene rings and aggregation of fluoroalkyl chains. Dynamic light scattering measurements showed that meso-styrene dimers bearing two fluoroalkyl end-groups can form the nanometer size-controlled self-assemblies through the intermolecular π-stacking of benzene rings and aggregation of end-capped fluoroalkyl groups in methanol. Figure
Self-assembled meso-perfluorohexylated styrene dimer [C6F13–CH2CHPh–CHPh–CH2–C6F13] based on π-stacking of benzene rings and aggregation of fluoroalkyl chains: Fluorous domains are constructed by self-assembly of fluoroalkyl chains. 相似文献
78.
Yuki Goto Masahiro Shiosaki Takeshi Hanamoto Masato Yoshida Hideo Sawada 《Colloid and polymer science》2013,291(5):1211-1217
Fluoro(silyl)acetylenes, which were prepared by reaction of 1,1-difluoroethylene with silyl chlorides, reacted with triethylamine to give dark-brown colored polyfluoro(silyl)acetylene powders in excellent to moderate isolated yields. In contrast, the corresponding nonfluorinated acetylene was unable to react with triethylamine at all to afford poly(silyl)acetylene under similar conditions. Polyfluoro(silyl)acetylenes thus obtained were nanometer size-controlled cubic fine particles with a good dispersibility and stability in a variety of solvents. These polyfluoro(silyl)acetylene nanoparticles exhibited clear absorption and emission spectra related to the conjugated units in polymer main chain. Furthermore, these polyfluoro(silyl)acetylene nanoparticles were applied to the surface modification of poly(methyl methacrylate) [PMMA] film to exhibit a higher oleophobicity imparted by fluorine on their surface, compared to that on the reverse side. Figure
New polyfluoro(silyl)acetylenes were prepared by reaction of the creesponding fluoro(silyl)acetylenes with triethylamine in excellent to moderate isolated yields. In contrast, the corresponding nonfluorinated silylacetylene was unable to give poly(silyl)acetylene under similar conditions. These polyfluoro(silyl)acetylenes thus obtained can form the nanometer size-controlled cubic fine particles (within 100 nm) in a variety of solvents. 相似文献
79.
Fujiko Iwasaki Seui Kakuma Satoshi Yoshida Shin Murata Masanori Yasui 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):515-516
Abstract The deformation electron-density distributions of 6a-thia-1,3,4,6-tetraazapentalene derivatives (I, II) and bis(phenylthio)dibenzothiophene (III) were investigated by the X-ray diffraction method. For I and II, a structure around the hypervalent S-N bonds is a trigonal bipyramid with equatorial sp2 hybrid of S-C bond and lone-pair electrons and apical polarized S-N bonds. In 111 lone-pair electron densities are observed perpendicular to the thiophene ring and the C-S-C sulfide planes. 相似文献
80.
Kenichiro Todoroki Hiroki Hashimoto Kazuyuki Machida Miki Itoyama Tadashi Hayama Hideyuki Yoshida Hitoshi Nohta Manabu Nakashima Masatoshi Yamaguchi 《Journal of separation science》2013,36(2):232-238
In this study, we combined a column‐switching system with a fluorous scavenging derivatization method to develop a fully automated reagent peak‐free LC fluorescence detection protocol for the analysis of highly polar carboxylic acids. In this method, highly polar carboxylic acids were derivatized with fluorescent 1‐pyrenemethylamine in the presence of 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide and 1‐hydroxy‐1H‐benzotriazole. Residual excess of the unreacted reagent was tagged with 2‐(perfluorooctyl)ethyl isocyanate and then removed selectively using a fluorous column‐switching system placed in front of an analytical reversed‐phase column. The signal of the fluorous‐tagged unreacted reagent was completely absent in the resulting chromatograms; therefore, it did not interfere with the quantification of each acid especially those eluted before 20 min. The detection limits (S/N = 3) for the examined acids were in the range from 4.0 to 22 fmol per injection. We have applied this method to comparative analysis of highly polar carboxylic acids in urine samples obtained from diabetes mellitus type‐II model mice and their control. 相似文献