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151.
152.
Synthesis and Photocatalytic Activity of Titania Pillared Clays 总被引:13,自引:0,他引:13
T. Kaneko H. Shimotsuma M. Kajikawa MISSING END TAG Hatamachi T. Kodama Y. Kitayama 《Journal of Porous Materials》2001,8(4):295-301
TiO2-pillared clays such as montmorillonite, saponite and mica were prepared with an intercalation of polynuclear titanium complex formed by the reaction of Ti(i-C3H7O)4 and acetic acid. Characterization of the products was performed by XRD, XPS, IR, UV-V spectra, the measurement of surface area and pore size distribution. The photocatalytic decomposition of carboxylic acids has been studied on TiO2-pillared montmorillonite, saponite and mica. TiO2-pillared mica showed higher catalytic activity than TiO2 for the photocatalytic decomposition of acetic acid and adipic acid. On the contrarily, TiO2 was the most active catalyst and TiO2-pillared mica showed low activity for the photocatalytic decomposition of capric acid. The results show that the molecular size of carboxylic acid contributes to the catalytic activity of TiO2-pillared clays. 相似文献
153.
Short communication: Amino acids antagonistic to the amino acids inhibitory for growth rate of mixed ruminal bacteria 总被引:1,自引:0,他引:1
Antagonism of some amino acids (AA) to the inhibitory effects of other AA (Ile, Phe, and Thr) on the growth rate of mixed ruminal bacteria was investigated. In vitro growth rate of the mixed ruminal bacteria was inhibited when the 3 inhibitory AA (1 mM each) were each added to individual control treatments in which an ammonium salt was included as a sole N source. The inhibitory effect caused by Ile was relieved by addition of Leu or Val (equimolar to Ile), and no significant inhibition was shown when both Leu and Val were added together with Ile. The growth inhibition caused by Phe was also alleviated by supplementing with Trp, and was completely negated by adding Tyr. The inhibitory effect of Thr, on the other hand, was not affected by addition of Lys or Met (which are synthesized using a common pathway with Thr), but was mitigated by supplementation with Glu, Ser, Val, Ala, or Gln. Among the antagonistic AA, Leu, Val, Trp, Tyr, and Glu were indispensable for the maximum growth rate of the ruminal bacteria under the experimental condition of supplementation of amino-N, the removal of which from a mixture of 20 protein AA caused the growth rate to decline. Removals of Ile along with Leu or Val or both, of Phe along with Trp or Tyr, and of Thr along with Glu recovered the promotion of bacterial growth rate. It was concluded that inhibitions of the bacterial growth rate caused by Ile, Phe, or Thr could be antagonized by some other AA (Leu, Val, Tyr, Trp, or Glu), and the role of these latter AA as relievers of the inhibitory effects could explain why they are indispensable for maximum growth rate of ruminal bacteria. 相似文献
154.
A behavior genetic analysis of the personality dimension of ego development, as assessed by the Washington University Sentence Completion Test, was carried out on a sample of 45 pairs of monozygotic twins and 28 pairs of same-sex dizygotic twins. The twins ranged in age from 16 to 70 years at the time of assessment, had been separated during infancy, and had been raised apart in adoptive homes before being reunited in adulthood. Analyses indicated that reared-apart twins were similar in trait levels of ego development and that such similarity could not solely be attributed to measured similarity in cognitive ability, including verbal reasoning. Estimates of broad similarity for ego development (46%) were comparable to values reported for other major personality dimensions. Phenotypic variance in adult levels of ego development appears to have substantial genetic and environmental sources. 相似文献
155.
Y. Kajikawa T. Nukami M. C. Flemings 《Metallurgical and Materials Transactions A》1995,26(8):2155-2159
Pressureless infiltration of ceramic preforms by molten aluminum is described. The preforms are SiC with varying amounts of
particulate Al, Ti, and Ni. Infiltrants employed are pure Al and Al-12.5 wt pct Si. It is shown that a pressure differential
within the preform is required for infiltration, and measurements are made of pressure changes in the preforms during infiltration.
Results indicate that atmospheric pressure is essential for infiltration but that capillarity may play a role as well.
T. NUKAMI, formerly Research Assistant, Massachusetts Institute of Technology 相似文献
156.
157.
158.
Jun Suzurikawa Sho Fujimoto Kousei Mikami Hiroshi Jonai Takenobu Inoue 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(6):832-834
To prevent individuals with thermoregulatory dysfunction from becoming hyperthermic in a hot environment, we propose a back‐cooling (BC) system with Peltier devices mounted on a wheelchair backrest. Here, we characterize the changes in thermoregulatory responses induced by BC in order to confirm the feasibility of the proposed system. A cooling experiment in a climate chamber at 33°C with six able‐bodied subjects demonstrated that the amount of sweating and systolic blood pressure were significantly lower in the BC trials than in the no‐cooling trials, providing preliminary evidence that BC can partially replace thermoregulatory responses and reduce the heat burden. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
159.
Continuous Band‐Filling Control and One‐Dimensional Transport in Metallic and Semiconducting Carbon Nanotube Tangled Films 下载免费PDF全文
Hidekazu Shimotani Satoshi Tsuda Hongtao Yuan Yohei Yomogida Rieko Moriya Taishi Takenobu Kazuhiro Yanagi Yoshihiro Iwasa 《Advanced functional materials》2014,24(22):3305-3311
Field‐effect transistors that employ an electrolyte in place of a gate dielectric layer can accumulate ultrahigh‐density carriers not only on a well‐defined channel (e.g., a two‐dimensional surface) but also on any irregularly shaped channel material. Here, on thin films of 95% pure metallic and semiconducting single‐walled carbon nanotubes (SWNTs), the Fermi level is continuously tuned over a very wide range, while their electronic transport and absorption spectra are simultaneously monitored. It is found that the conductivity of not only the semiconducting but also the metallic SWNT thin films steeply changes when the Fermi level reaches the edges of one‐dimensional subbands and that the conductivity is almost proportional to the number of subbands crossing the Fermi level, thereby exhibiting a one‐dimensional nature of transport even in a tangled network structure and at room temperature. 相似文献
160.
Takenobu Ishii Montserrat Ruiz-Torruella Kenta Yamamoto Tsuguno Yamaguchi Alireza Heidari Roodelyne Pierrelus Elizabeth Leon Satoru Shindo Mohamad Rawas-Qalaji Maria Rita Pastore Atsushi Ikeda Shin Nakamura Hani Mawardi Umadevi Kandalam Patrick Hardigan Lukasz Witek Paulo G. Coelho Toshihisa Kawai 《International journal of molecular sciences》2022,23(10)
It is well known that Semaphorin 4D (Sema4D) inhibits IGF-1-mediated osteogenesis by binding with PlexinB1 expressed on osteoblasts. However, its elevated level in the gingival crevice fluid of periodontitis patients and the broader scope of its activities in the context of potential upregulation of osteoclast-mediated periodontal bone-resorption suggest the need for further investigation of this multifaceted molecule. In short, the pathophysiological role of Sema4D in periodontitis requires further study. Accordingly, attachment of the ligature to the maxillary molar of mice for 7 days induced alveolar bone-resorption accompanied by locally elevated, soluble Sema4D (sSema4D), TNF-α and RANKL. Removal of the ligature induced spontaneous bone regeneration during the following 14 days, which was significantly promoted by anti-Sema4D-mAb administration. Anti-Sema4D-mAb was also suppressed in vitro osteoclastogenesis and pit formation by RANKL-stimulated BMMCs. While anti-Sema4D-mAb downmodulated the bone-resorption induced in mouse periodontitis, it neither affected local production of TNF-α and RANKL nor systemic skeletal bone remodeling. RANKL-induced osteoclastogenesis and resorptive activity were also suppressed by blocking of CD72, but not Plexin B2, suggesting that sSema4D released by osteoclasts promotes osteoclastogenesis via ligation to CD72 receptor. Overall, our data indicated that ssSema4D released by osteoclasts may play a dual function by decreasing bone formation, while upregulating bone-resorption. 相似文献