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Katsumi Katoh Shunsuke Ito Yuji Ogata Jun-ichi Kasamatsu Hiroshi Miya Masaaki Yamamoto Yuji Wada 《Journal of Thermal Analysis and Calorimetry》2010,99(1):159-164
In order to prevent the spontaneous ignition of nitrocellulose (NC), NC is stabilized by washing with industrial water in
its synthesis process. However, there is a possibility that the components in industrial water contribute to the thermal stability
of NC. In this way, the purpose of this study is to clarify the effect of industrial water components on the thermal stability
of NC. In experiments, a heat flux calorimeter was used to observe the thermal behavior of NC with the residue of vaporized
industrial water. The induction period of heat release of NC with 2-mass% residues was approximately 2–5 h shorter than that
of NC alone whose induction period was observed at 7 h. Those results indicate that the residue destabilized NC. On the other
hand, when the additive amount of the residue was increased, the induction period gradually increased as well. Based upon
these results, we assume that inorganic salts contributing to stabilization and destabilization competitively coexist in the
industrial water components. The same thermal analysis was performed on NC with CaCO3, CaSO4, CaCl, ZnSO4, NaCl, and CuCl. Those salts are predicted to exist in the industrial water. In the results, the induction period of NC with
2-mass% CaCO3 was approximately 15-h longer than that of NC alone, while the induction period with the inorganic salts CaSO4, CaCl, ZnSO4, NaCl, and CuCl was 4–5-h shorter. Therefore, when the industrial water components accumulate in NC, the destabilization
by inorganic salts such as CaSO4, CaCl, ZnSO4, NaCl, and CuCl and the stabilization by compounds such as CaCO3 are thought to countervail against each other. 相似文献
34.
Satoshi Motodate Takuya Kobayashi Mikio Fujii Prof. Tomoyuki Mochida Dr. Taichi Kusakabe Shigeki Katoh Prof. Hiroyuki Akita Prof. Keisuke Kato 《化学:亚洲杂志》2010,5(10):2221-2230
Bis(oxazoline)‐palladium(II) catalyzed carbonylation of homopropargyl alcohols afforded acyclic methoxyacrylate 2 and 6‐membered lactone 3a , 3b , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k in good combined yield. In the case of propargyl alcohols, 5‐membered lactones 3p , 3q , 16 were obtained in moderate yields. The one‐pot synthesis of kawa lactones 3a , 3r , 3s and formal synthesis of dihydroxycystothiazole A and dihydroxycystothiazole C are presented. To elucidate the stereochemistry of (+)‐annularin G and (?)‐annularin H, the first asymmetric syntheses of these natural products were achieved. 相似文献
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Michio Zenki Makiko Ideshima Miwa Taniguchi Ayako Katoh Takashi Yokoyama 《Analytical sciences》2005,21(5):517-520
A circulatory flow-injection method (cyclic FIA) for the repetitive determination of zinc has been proposed. The procedure involves the use of 2-(5-bromo-2-pyridylazo)-5-[N-n-propyl-N-(3-sulfopropyl)amino]phenol (5-Br-PAPS) together with EDTA as a reagent carrier solution, which is recycled in a single-line flow system via a reservoir. The formed 5-Br-PAPS-Zn(II) complex was measured spectrophotometrically at 552 nm, and the signal intensity corresponded to the zinc concentration. After passing through a flow-through cell, the carrier stream then returned to the reservoir, and the main reagent, 5-Br-PAPS, was successfully regenerated by a ligand-exchange reaction with EDTA, allowing the repetitive determination of zinc. The calibration curve for zinc was linear in the concentration range from 0.4 to 10.0 mg dm(-3) with a correlation coefficient of 0.9995 (n = 6). The detection limit of this method was 0.02 mg dm(-3) (S/N= 3). This method allowed as many as 300 repetitive determinations of 2.0 mg dm(-3) zinc solution with only 100 cm3 of the circulating carrier solution, providing a reduction in the consumption of reagents and an elimination of waste, an important approach towards clean chemistry. 相似文献
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In this paper, we report on an experimental technique for the simultaneous measurement of temperature and three components of velocity in a three-dimensional thermal flow using scanning liquid-crystal thermometry and stereo velocimetry. The temperature is measured by the color image analysis of the liquid-crystal particles suspended in a fluid, while the three velocity components are measured by stereo particle image velocimetry (stereo PIV) with the aid of tracer particles. The measurement is carried out by scanning the light-sheet plane while capturing the sequential color images of the liquid crystals and tracer particles. This measurement allows the reconstruction of the three-dimensional distribution of temperature and full velocity field simultaneously. The present experimental technique is applied to the horizontal fluid layer of a turbulent Rayleigh-Bérnard convection and the three-dimensional structures of thermal plumes are evaluated. The experimental results indicate that the structures of plumes are often correlated with the vertical velocity of the fluid, but they behave randomly in space, influenced by the large-scale turbulence evident in the middle of the fluid layer. 相似文献
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Katsumi Katoh Shunsuke Ito Yusuke Wada Eiko Higashi Yasuhiro Suzuki Kazuhiro Kubota Katsuyuki Nakano Yuji Wada 《The Journal of chemical thermodynamics》2011,43(8):1229-1234
In this study, we examined the reaction hazard during the hydrosilylation reaction between trichlorosilane (TCS) and 1,6-divinyl(perfluorohexane) (FDV) in the presence of a butanol solution of chloroplatinic acid (Pt-Cat) as the catalyst. Assuming the three industrial risks of excessive addition of Pt-Cat, contamination by iron rust and mixing with cooling water, we observed the temperature and pressure change of TCS/FDV with an excessive amount of Pt-Cat, TCS/FDV/Pt-Cat with Fe2O3 and TCS/FDV/Pt-Cat with distilled water, using an accelerating rate calorimeter (ARC). The temperature and pressure greatly increased, especially in the sample with Fe2O3. For instance, in TCS/FDV/Pt-Cat with 1.5 wt.% Fe2O3, the heat release rate exceeded 624 K · min?1 and the pressure rose above 25 MPa during the exothermic reaction. 相似文献