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121.
Makoto Sugiyama Yutaka FujimotoTakayuki Yanagida Yuui YokotaJan Pejchal Yuki FuruyaHidehiko Tanaka Akira Yoshikawa 《Optical Materials》2011,33(6):905-908
Nd 0.1%, 0.5%, 1% and 3% doped Lu3Al5O12 (Nd:LuAG) single crystals were grown in the nitrogen atmosphere by the micro-pulling down (μ-PD) method. The grown crystals had a single-phase confirmed by powder XRD analysis. In absorption spectra, some weak absorption lines due to Nd3+ 4f-4f transitions were observed and their intensity increased with the increase of Nd concentration. When excited by 241Am α-ray, a broad emission peak due to defects in the host lattice at 320 nm and some sharp lines due to Nd3+ 4f-4f transitions at wavelength longer than 400 nm were observed. The decay time profiles of Nd:LuAG under γ-ray excitation were well approximated by two exponential function of 340-760 ns and 3-5 μs for each sample. By pulse height measurement using 137Cs, Nd 0.5%:LuAG showed the highest light yield of 7600 ± 760 photons/MeV. 相似文献
122.
123.
Ryo Miura Tetsuo Fujishima Hiromichi Uchimura Kensuke Toda Makoto Kobayashi Naoko Ashikawa Akio Sagara Naoaki Yoshida Yuji Hatano Yasuhisa Oya Kenji Okuno 《Fusion Engineering and Design》2013,88(9-10):1827-1830
The D2+ fluence dependence on deuterium (D) retention was studied to clarify the D retention mechanism in tungsten. The additional D desorption stage was observed around 660 K in the TDS spectrum for a sample implanted with D2+ up to the fluence of 1023 D+ m?2, which desorption stage was not observed the D2+ implanted sample with the fluence less than 1022 D+ m?2. The TEM observation showed that the highly dense voids were formed in tungsten by D2+ implantation with the fluence of 1023 D+ m?2, considering that the D would be trapped by voids. To understand the D trapping by voids in C+ implanted tungsten, C+–D2+ sequential implantation experiments at various C+ implantation temperatures were performed. It was found that the amount of D desorbed around 560 K was increased by increasing the C+ implantation temperature. The formation of the voids was observed with increasing the C+ implantation temperature by TEM, indicating that the increase of D desorption around 560 K was caused by the formation of voids. However, the desorption temperature of D trapped by voids in C+ implanted sample was lower than that in D2+ implanted one. TEM observation and XPS measurement indicated that this difference was caused by the increase of void size and/or the presence of implanted carbon. 相似文献
124.
Hideharu Mori Yosuke Saito Eri Takahashi Kazuhiro Nakabayashi Atsuhiko Onuma Makoto Morishima 《Reactive and Functional Polymers》2013,73(4):658-667
Novel organic–inorganic hybrids with sulfonic acid groups were prepared using random copolymers composed of vinyl sulfonate esters and vinyl trialkoxysilanes. Five vinyl sulfonate esters with different substituent groups were employed as protecting monomers for the production of the poly(vinyl sulfonic acid) component, and three vinyl trialkoxysilanes were used as cross-linkable monomers. Free radical and reversible addition-fragmentation chain transfer (RAFT) copolymerizations were performed for the production of random copolymers with two different functional groups. The selective deprotection of the sulfonate esters of the copolymers proceeded smoothly and resulted in the formation of copolymers with lithium vinyl sulfonate units and cross-linkable trialkoxysilane units. The co-condensation of the trialkoxysilane moieties in the deprotected copolymers with cross-linkers yielded transparent hybrid films that contained lithium sulfonate groups without aromatic rings or ester linkages. 相似文献
125.
Qingjun Zhu Makoto Takiguchi Tohru Setoyama Toshiyuki Yokoi Junko N. Kondo Takashi Tatsumi 《Catalysis Letters》2011,141(5):670-677
Abstract
Cr/silicalite-1 and Cr/H[B]MFI catalysts were prepared by the impregnation method, and Cr/H[B]MFI were further treated by steaming. The catalysts were employed for the oxidative dehydrogenation of propane to propylene with CO2 as the oxidant. Cr/H[B]MFI showed significantly higher catalytic activity than Cr/silicalite-1, and steamed Cr/H[B]MFI was superior in the reaction stability to Cr/H[B]MFI. The nature of the supported chromium species have been characterized by a number of physicochemical techniques, such as Raman, UV–vis and NMR. It is concluded that the steaming led to the auto-reduction of some Cr6+ to Cr3+, and resultant Cr3+ species might be located near the boron center in the borosilicate framework to counterbalance the negative charge of the framework. The transformation of Cr6+ species to Cr3+ species, facilitated by the steaming process and the presence of boron in the catalyst, is responsible for the enhanced stability of oxidative dehydrogenation of propane to propylene with carbon dioxide as the oxidant. 相似文献126.
Makoto Misono 《Catalysis Reviews》2013,55(2-3):269-321
Heteropolyanions are polymeric oxoanions which are formed by the condensation of more than two different oxoanions [Eq. (1)l. Polyanions consisting of one kind of oxoanion are called isopolyanions [Eq. (2)]. Acidic elements such as Mo, W, V, Nb, and Ta are present as oxoanions in aqueous solutions and polymerize to form polyanions at low pH. Free acids (or acid forms) of these species are called heteropoly and isopoly acids, respectively. Here, the term “heteropoly compounds” is used for heteropoly acids and their salts. 相似文献
127.
Acid catalyzed reactions of 1-octene on TiO2 in sub- and supercritical water were investigated (T = 250-450 °C, P = 11-33 MPa). The main products were 2-octene and 2-octanol. Additionally, other liner C8 alkenes and liner secondary C8 alcohols were produced as by-products. Through kinetic analysis, acid catalyzed reactions can divide into the reaction catalyzed by Lewis acidic sites on TiO2 and the reaction catalyzed by protons produced by the dissociation of water molecules. Each type of the reaction is affected by water density or ionic product of water, respectively, therefore, reaction mechanism changes with temperature and pressure. From the contribution of each reaction type, the temperature dependence of cis/trans ratio of produced 2-octene could also be explained. 相似文献
128.
Kenji Imai Koji Takai Tatsunori Hanai Makoto Shiraki Yusuke Suzuki Hideki Hayashi Takafumi Naiki Youichi Nishigaki Eiichi Tomita Masahito Shimizu Hisataka Moriwaki 《International journal of molecular sciences》2014,15(7):11294-11306
Obesity-related metabolic abnormalities, including adipokine imbalance and chronic inflammation, are involved in liver carcinogenesis. Chemerin, a novel adipokine, plays a critical role in adipogenesis, energy metabolism, and inflammation. We evaluated the impact of serum chemerin levels on liver functional reserves in hepatocellular carcinoma (HCC) patients and on the recurrence and prognosis of HCC. This study included 44 patients with any stage of HCC who underwent curative treatment at Gifu Municipal Hospital (Gifu, Japan) between 2006 and 2007. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Serum albumin levels (Pearson’s correlation coefficient; r = 0.3110, p = 0.0399), platelet counts (r = 0.4159, p = 0.0050), and prothrombin times (r = 0.3775, p = 0.0115) were significantly correlated with serum chemerin levels in patients with HCC, and they were inversely correlated with Child-Pugh scores (r = −0.3732, p = 0.0126), serum alanine aminotransferase levels (r = −0.3864, p = 0.0105), and total bilirubin levels (r = −0.4023, p = 0.0068). Among these variables, a multiple comparison test identified that platelet counts and total bilirubin levels were associated with serum chemerin levels (p < 0.0083). No significant correlation was found between serum chemerin levels and recurrence-free survival (p = 0.3691) or overall survival (p = 0.7916). In HCC patients, serum chemerin concentrations were correlated with liver functional reserves and platelet counts, but not with recurrence or prognosis. 相似文献
129.
The performance of the Taylor‐Couette flow apparatus as a heat sterilizer is numerically investigated. The destruction of Clostridium botulinum and thiamine (vitamin B1) was selected as model reaction. When Taylor vortices were formed in the annular space, the heat transfer significantly enhanced as compared to the case without vortex flow. As a result, the equivalent lethality calculated from the temperature field increased, which is regarded as a quantum leap. Conversely, the improvement of heat transfer induced destruction of thiamine. These results suggest that there is a trade‐off relationship between the enhancement of heat transfer and the avoidance of thermal destruction of nutritional components. In conclusion, the Taylor‐Couette flow sterilizer has the potential for process intensification in heat sterilization processes. 相似文献
130.
New catalytic technologies in Japan 总被引:9,自引:0,他引:9
Recent trends in R&D of catalytic technology in Japan (cleaner and more efficient production, environmental catalysts, and recycling processes) are overviewed and examples of recent achievements are listed. Examples are then described as zeolite-catalyzed organic reactions recently commercialized and expected to be commercialized: hydration of cyclohexene, synthesis of pyridine derivatives and gas-phase Beckmann rearrangement of cyclohexanone oxime. Finally, as an example of environmental catalysts, the NOx storage–reduction type three-way automobile catalyst, is introduced. 相似文献