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排序方式: 共有746条查询结果,搜索用时 31 毫秒
91.
Ryo Watanabe Yasushi Sekine Masahiko Matsukata Eiichi Kikuchi 《Catalysis Letters》2009,131(1-2):54-58
We investigated novel LaMnOx perovskite-oxide (ABO3) catalysts for effective catalytic dehydrogenation of ethylbenzene to produce styrene monomer. Comparison with industrial Fe–K catalyst, our La0.8Ba0.2Mn0.6Fe0.4O3-δ catalyst showed higher activity. Results show that the A-site in perovskite-type oxides affected catalytic dehydrogenation activities and that the B-site affected stability of the activities. 相似文献
92.
Lead recovery from lead zirconate (PbZrO(3)) ceramics was investigated using a wet ball-mill treatment in H(2)SO(4) aqueous solution. Subsequently crystalline alpha-zirconium phosphate (alpha-Zr(HPO(4))(2).H(2)O) was synthesized using a hydrothermal technique in order for the resource recovery of zirconium in the wastewater after the wet ball-mill treatment. A wet ball-mill treatment in 4.5M H(2)SO(4) aqueous solution for 24h was capable of converting more than 99.9% of the Pb initially included in the PbZrO(3) to solid state PbSO(4) with a purity of 98%. On the other hand, the Zr in the PbZrO(3) was dissolved into the acidic solution during the treatment. The Pb and Zr metal elements coexisting in PbZrO(3) were successfully separated by the wet ball-mill technique. Then, resource recovery of zirconium in the wastewater was examined. Crystalline alpha-Zr(HPO(4))(2).H(2)O was synthesized by hydrothermal treatments in 3.1-12.5M H(3)PO(4) aqueous solutions at temperatures of 120-240 degrees C for a duration of 70h. The hydrothermally prepared powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and then they were also evaluated in terms of cation exchange capacity (CEC) measurement and thermogravimetric (TG) analysis. 相似文献
93.
This paper proposes a method for generating a basis translation matrix between isomorphic extension fields. To generate a basis translation matrix, we need the equality correspondence of a basis between the isomorphic extension fields. Consider an extension field Fpm where p is characteristic. As a brute force method, when pm is small, we can check the equality correspondence by using the minimal polynomial of a basis element; however, when pm is large, it becomes too difficult. The proposed methods are based on the fact that Type I and Type II optimal normal bases (ONBs) can be easily identified in each isomorphic extension field. The proposed methods efficiently use Type I and Type II ONBs and can generate a pair of basis translation matrices within 15 ms on Pentium 4 (3.6 GHz) when mlog2 p = 160. 相似文献
94.
Ryo Inagaki Fumika Ito Yuko Shimamura 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(2):236-243
The effects of the presence of chloride on the formation of 3-monochloro-1,2-propanediol fatty acid esters (3-MCPDEs) and glycidol fatty acid esters (GEs) in saltwater fish, meats and acylglycerols (diacylglycerol and triacylglycerol) during heating were investigated in this study. Five saltwater fish species (salmon, saury, yellowtail, mackerel and Spanish mackerel) were grilled with a fish griller. 3-MCPDEs and GEs were detected in all of the grilled fish samples. The total amount of GEs was higher than 3-MCPDEs. Beef and pork patties with or without sodium chloride (1.5%) were cooked using gaseous fuel. The formation of 3-MCPDEs was significantly increased by the addition of sodium chloride to the meat patties, whereas the concentration of GEs in the cooked meat patties was not changed by the content of sodium chloride. Hexadecane solutions of diacylglycerol or triacylglycerol containing FeCl3 were heated at 240°C. The formation of 3-MCPDEs was greatly increased by adding FeCl3 to the solutions of triacylglycerol. The amounts of 3-MCPDEs decreased with the extension of the heating time. From these results, it is suggested that 3-MCPDEs and GEs are formed in saltwater fish and meats by cooking, and that the formation of 3-MCPDEs was affected by chloride in foodstuffs. 相似文献
95.
Ochiai Y Batmunkh O Ogasawara K Mochizuki M Hondo R Ueda F 《International journal of food microbiology》2008,127(1-2):12-17
Phylogenetic analyses were carried out on a total of 118 Listeria monocytogenes isolates from foods or food processing environments, and 7 isolates from listeriosis patients in Japan to evaluate the genetic variation in the pathogen in this country. Isolates of serotypes 1/2a, 1/2b and 4b were mainly examined to assess the risk of exposure of humans to L. monocytogenes from foods in Japan. The nucleotide sequences of the part of the iap gene that contains the region encoding the threonine-asparagine repeat units were determined in order to construct phylogenetic trees of the isolates investigated. A phylogram showed high genetic diversity among lineage 2 isolates, while the lineage 1 isolates showed clonal characteristics. The results of the genetic analyses suggested the presence of rare putative lineage 3 isolates and epidemic clone I (ECI) isolates in foods in Japan. The results showed that ECI was also isolated from listeriosis patients. The genetic variation in L. monocytogenes in Japan reported here suggests the necessity of monitoring the pathogen in foods and environments in addition to surveillance of listeriosis patients. 相似文献
96.
Kazunari Ushida Hironori Hatanaka Ryo Inoue Takamitsu Tsukahara Glyn O. Phillips 《Food Hydrocolloids》2011
Abdominal obesity is the most prevalent manifestation of metabolic syndrome. The anti-obese effects of dietary fiber is generally accepted, but specifically the anti-obese properties of the dietary fiber, gum arabic (GA) has not been well studied. In this investigation, we offered GA to the female 90 days old mice in the form of drink (1% w/v) for 180 days. Such GA in drinking water reduced age-dependent fat deposition in the visceral adipose tissue and improved the gastrocnemius muscle reduction. This inhibition of fat deposition effect is due to the β3-adrenergic stimulation of adipocytes in which TNFα down-regulation is probably involved. Modification of large intestinal microflora, as evidenced by a modification of cecal short-chain fatty acid profile and of 16S rDNA profile, may contribute to such reduction in TNFα expression in the adipose tissues. 相似文献
97.
An oxathiolanone derivative of rutin could be produced in the stomach after the ingestion of rutin containing foods, and the oxathiolanone derivative could be hydrolysed to an oxathiolanone derivative of quercetin (quercetin-oxathiolanone) in the intestine. Quercetin-oxathiolanone as well as quercetin inhibited xanthine oxidase. Approximately 0.05 μM quercetin-oxathiolanone inhibited the activity by 50%, whereas 50% inhibition by quercetin was observed at approximately 0.4 μM. The results suggested that quercetin-oxathiolanone can be used as an effective inhibitor of xanthine oxidase and that the ingestion of rutin-rich foods may be useful to prevent the increase in the blood concentration of uric acid. 相似文献
98.
Shuichi Ichikawa Masanori Akinaka Hisashi Hata Ryo Ikeda Hiroshi Yamamoto 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(4):367-375
Although a programmable logic controller (PLC) has been widely adopted for the sequence control of industrial machinery, its performance does not always satisfy the recent requirements in large and highly responsive systems. With the state‐of‐the‐art field programmable gate array (FPGA) technology, it is possible to implement a control program with hard‐wired logic for higher response and reduced implementation cost/space. This approach is also worthwhile for transmigration of legacy PLC software into forthcoming FPGA‐based control hardware. This study presents a systematic method to implement a hard‐wired sequence control from PLC software. PLC instructions are converted into VHDL codes, and then implemented as logic circuit with various peripheral functions. Productive PLC programs were examined with Mitsubishi Electric FX2N PLC and Altera Stratix II FPGA, and were shown to fit into a common FPGA chip. A straightforward Sequential design was estimated to be 184 times faster than PLC, while a performance‐oriented Flat design was estimated to be 44 times faster than Sequential design (i.e., 8050 times faster than PLC). A practical perfect layer winder system was actually built and successfully operated with our FPGA control board, whose logic design was implemented with our tools. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
99.
SeyedHosein Payandeh Daniel Rentsch Zbigniew Łodziana Ryo Asakura Laurent Bigler Radovan Černý Corsin Battaglia Arndt Remhof 《Advanced functional materials》2021,31(18):2010046
Hydroborate-based solid electrolytes have recently been successfully employed in high voltage, room temperature all-solid-state sodium batteries. The transfer to analogous lithium systems has failed up to now due to the lower conductivity of the corresponding lithium compounds and their high cost. Here LiB11H14 nido-hydroborate as a cost-effective building block and its high-purity synthesis is introduced. The crystal structures of anhydrous LiB11H14 as well as of LiB11H14-based mixed-anion solid electrolytes are solved and high ionic conductivities of 1.1 × 10−4 S cm−1 for Li2(B11H14)(CB11H12) and 1.1 × 10−3 S cm−1 for Li3(B11H14)(CB9H10)2 are obtained, respectively. LiB11H14 exhibits an oxidative stability limit of 2.6 V versus Li+/Li and the proposed decomposition products are discussed based on density functional theory calculations. Strategies are discussed to improve the stability of these compounds by modifying the chemical structure of the nido-hydroborate cage. Galvanostatic cycling in symmetric cells with two lithium metal electrodes shows a small overpotential increase from 22.5 to 30 mV after 620 h (up to 0.5 mAh cm−2), demonstrating that the electrolyte is compatible with metallic anodes. Finally, the Li2(B11H14)(CB11H12) electrolyte is employed in a proof-of-concept half cell with a TiS2 cathode with a capacity retention of 82% after 150 cycles at C/5. 相似文献
100.
Noritaka Yonezawa Hideki Murakami Satoru Demura Satoshi Kato Shinji Miwa Katsuhito Yoshioka Kazuya Shinmura Noriaki Yokogawa Takaki Shimizu Norihiro Oku Ryo Kitagawa Makoto Handa Ryohei Annen Yuki Kurokawa Kazumi Fushimi Eishiro Mizukoshi Hiroyuki Tsuchiya 《International journal of molecular sciences》2021,22(4)
We evaluated the abscopal effect of re-implantation of liquid nitrogen-treated tumor-bearing bone grafts and the synergistic effect of anti-PD-1 (programmed death-1) therapy using a bone metastasis model, created by injecting MMT-060562 cells into the bilateral tibiae of 6–8-week-old female C3H mice. After 2 weeks, the lateral tumors were treated by excision, cryotreatment using liquid nitrogen, excision with anti-PD-1 treatment, and cryotreatment with anti-PD-1 treatment. Anti-mouse PD-1 4H2 was injected on days 1, 6, 12, and 18 post-treatment. The mice were euthanized after 3 weeks; the abscopal effect was evaluated by focusing on growth inhibition of the abscopal tumor. The re-implantation of frozen autografts significantly inhibited the growth of the remaining abscopal tumors. However, a more potent abscopal effect was observed in the anti-PD-1 antibody group. The number of CD8+ T cells infiltrating the abscopal tumor and tumor-specific interferon-γ (IFN-γ)-producing spleen cells increased in the liquid nitrogen-treated group compared with those in the excision group, with no significant difference. The number was significantly higher in the anti-PD-1 antibody-treated group than in the non-treated group. Overall, re-implantation of tumor-bearing frozen autograft has an abscopal effect on abscopal tumor growth, although re-implantation of liquid nitrogen-treated bone grafts did not induce a strong T-cell response or tumor-suppressive effect. 相似文献