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81.
82.
Stochastic path-integral method for chemical reaction dynamics: Application to the full 3D H3 system
Masataka Nagaoka 《International journal of quantum chemistry》1996,60(7):1303-1310
A stochastic path-integral (SPI) technique for chemical reaction dynamics is explored. It is shown that this technique enables the direct computation of the transition amplitude with a finite space-time range, by generating a set of classical paths subject to simultaneous stochastic differential equations. The numerical values of the Boltzmann matrix elements for a harmonic potential are in good agreement with the analytical ones. Within the quantum transition state theory, the flux-flux autocorrelation function is also evaluated at 630 K for the H + H2 exchange reaction and is found to give a satisfactory agreement with the previous studies. To appraise the influence of the dimensionality, both one-dimensional Eckart potential and a full three-dimensional (3D) Liu-Siegbahn-Truhlar-Horowitz (LSTH) potential calculations have been performed. The calculated values of the Boltzmann matrix elements for the colinear and the full 3D cases are found to deviate slightly from each other in the lower temperature range. The 3D thermal rate constant is in very good agreement with the previous one. © 1996 John Wiley & Sons, Inc. 相似文献
83.
Takeo Yamaguchi Shin-Ichi Nakao Shoji Kimura 《Journal of polymer science. Part A, Polymer chemistry》1996,34(7):1203-1208
Using a plasma-induced graft polymerization technique, which is well known as a surface modification method, the grafted polymer was formed in pores of the porous material. This study examined the filling mechanism. Five thin porous films were sandwiched together, and employed as the substrate. The substrate was treated by plasma, and the change in surface tension and radical formation was measured for each sheet after the sheet was separated. The only surface on which surface-tension change was detected, was that of the sheet directly exposed to the plasma. Although plasma treatment made polymer radicals primarily on the outer surface of the sheet, the treatment also formed a few radicals inside the sheets. The radicals inside the sheets reacted with methylacrylate and grafted polymer formed in the pores. The location of grafted polymer depended on the balance between monomer diffusivity and reactivity. The grafting rate depended on which monomer solvent was used for the polymerization. Thus, the grafted membrane morphology could be controlled by varying the grating solvent composition. © 1996 John Wiley & Sons, Inc. 相似文献
84.
Pedro L. R. Guedes Carolina P. F. Carvalho Adriana A. F. Carbonel Manuel J. Simes Marcelo Y. Icimoto Jair A. K. Aguiar Maria Kouyoumdjian Marcos L. Gazarini Marcia R. Nagaoka 《Molecules (Basel, Switzerland)》2022,27(3)
During liver fibrogenesis, there is an imbalance between regeneration and wound healing. The current treatment is the withdrawal of the causing agent; thus, investigation of new and effective treatments is important. Studies have highlighted the action of chondroitin sulfate (CS) in different cells; thus, our aim was to analyze its effect on an experimental model of bile duct ligation (BDL). Adult Wistar rats were subjected to BDL and treated with CS for 7, 14, 21, or 28 days intraperitoneally. We performed histomorphometric analyses on Picrosirius-stained liver sections. Cell death was analyzed according to caspase-3 and cathepsin B activity and using a TUNEL assay. Regeneration was evaluated using PCNA immunohistochemistry. BDL led to increased collagen content with corresponding decreased liver parenchyma. CS treatment reduced total collagen and increased parenchyma content after 21 and 28 days. The treatment also promoted changes in the hepatic collagen type III/I ratio. Furthermore, it was observed that CS treatment reduced caspase-3 activity and the percentage of TUNEL-positive cells after 14 days and cathepsin B activity only after 28 days. The regeneration increased after 14, 21, and 28 days of CS treatment. In conclusion, our study showed a promising hepatoprotective action of CS in fibrogenesis induced by BDL. 相似文献
85.
Electron beam treatment of lignite-burning flue gas with high concentrations of sulfur dioxide and water 总被引:5,自引:0,他引:5
Hideki Namba Shoji Hashimoto Okihiro Tokunaga Ryoji Suzuki 《Radiation Physics and Chemistry》1998,53(6):673-681
Experiments were carried out to investigate the removals of SO2 and NOx from simulated lignite-burning flue gas containing SO2 (4800 ppm), NO (320 ppm) and H2O (22%) by electron beam irradiation. Removal efficiencies of SO2 and NOx were achieved to reach 97 and 88% at 70°C, and 74 and 85% at 80°C, respectively, with the dose of 10.3 kGy without NH3 leakage. The higher removal efficiencies of SO2 and NOx were observed in simulated lignite-burning flue gas than in coal-fired flue gas containing 800 ppm of SO2, 225 ppm of NO and 7.5% H2O at the same treatment condition. The higher removal efficiencies were attributed to the higher concentrations of SO2, H2O, and added NH3. Simulation calculations indicated that the higher concentrations of these components enhance the effective radical reactions to oxidize NO to form NO2 with HO2 radical, and to oxidize SO2 to form SO3 with OH radical and O2. The reactions of NOx with N and NH2 radicals to produce N2 and N2O also promote the NOx removal. By-product was determined to be the mixture of (NH4)2SO4 and NH4NO3 containing a small amount of H2SO4. 相似文献
86.
Takahiro Miyata Kozo Matsumoto Takeshi Endo Shigeaki Yonemori Shoji Watanabe 《Journal of polymer science. Part A, Polymer chemistry》2012,50(15):3046-3051
A styrene‐based monomer having a five‐membered cyclic carbonate structure, 4‐vinylbenzyl 2,5‐dioxoran‐3‐ylmethyl ether (VBCE), was prepared by lithium bromide‐catalyzed addition of carbon dioxide to 4‐vinylbenxyl glycidyl ether (VBGE). Radical polymerization of the obtained VBCE was carried out using 2,2′‐azobisisobutyronitrile as an initiator. PolyVBCE with number‐averaged molecular weight higher than 13,800 was obtained by a solution polymerization in N,N‐dimethylformamide, N,N‐dimethylacetamide, dimethyl sulfoxide, and methyl ethyl ketone. The glass transition temperature and 5 wt % decomposition temperature of the polyVBCE were determined to be 52 and 305 °C by differential scanning calorimetry and thermal gravimetry analysis, respectively. It was confirmed that a polymer consisting of the same VBCE repeating unit can be also obtained via chemical modification of polyVBGE, that is, a lithium‐bromide‐catalyzed addition of carbon dioxide to a polyVBGE prepared from a radical polymerization of VBGE. Further copolymerization of VBCE with styrene gave the corresponding copolymer in a high yield. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
87.
Yoshiyuki Koyano Norio Takenaka Yukinori Nakagawa Masataka Nagaoka 《Journal of computational chemistry》2010,31(14):2628-2641
88.
Hiroyuki Kawano Haruhiko Shimoji Shoji Yoshikawa Katsumasa Miyatake Kazumori Hama Shuji Nakamura 《Optical Review》2008,15(2):118-124
Alignment error of an image sensor relative to the optical axis of a star sensor head and alignment errors between four heads
were calculated from pictures taken in an orbital experiment. When comparing the image sensor alignment parameters in the
orbital test and a ground test, both values matched well. By determining the relative relationship of the four heads using
four pictures taken at the same moment in orbit and uploading the parameters to the star sensor system in orbit, the estimated
attitude error was improved from 0.29 to 0.17°, though the accuracy was limited by the ±0.2° determination accuracy of the
satellite itself. We estimated the attitude determination accuracy from separation angles between boresights of the four heads,
calculated from pattern matching between downloaded pictures and a star catalogue. The estimated accuracy, in terms of potential
optical performance, was 0.60 arcmin at 3σ, which is sufficient to satisfy the specification of 1 arcmin. 相似文献
89.
Yagi S Iwanaga T Kojima H Shoji Y Suzuki S Seno K Mori H Tokura Y Takigawa M Moriwaki S 《Photochemistry and photobiology》2002,76(6):669-671
We have developed a UV monitor with polycrystalline (poly-) gallium nitride (GaN) UV sensors and evaluated its performance from the viewpoint of its effectiveness for use with photosensitive dermatosis patients. The poly-GaN UV sensor is sensitive to UV light from 280 to 410 nm even without optical filters. The UV monitor is a portable self-data-acquisition instrument with a minimum detection level (defined as average UV intensity over 290 to 400 nm) of 2 microW/cm2 and can store UV dose data for 128 days. It allows easy measurement of four orders of magnitude of ambient UV intensity and dose from indoor light to direct solar radiation in summer. Trial use of the UV monitor by five xeroderma pigmentosum patients started in June 2000 and was carried out for 1 year. It was demonstrated that the UV monitor was useful in improving their quality of life. 相似文献
90.
Yoshida R Sakai T Ito S Yamaguchi T 《Journal of the American Chemical Society》2002,124(27):8095-8098
Self-oscillation of polymer chains in an aqueous solution has been achieved. The ruthenium catalyst for the Belousov-Zhabotinsky reaction was polymerized by using N-isopropylacrylamide and dissolved into the solution containing the BZ substrates. Periodical soluble-insoluble changes of the polymer chain were spontaneously induced by the BZ reaction. The conformational oscillations of the polymer were measured as the optical transmittance changes of the solution. This is the first report that rhythmical and reversible soluble-insoluble changes of polymer chains are realized under constant and homogeneous conditions. The transducing system from chemical energy of the BZ reaction to optical information has been constructed. 相似文献