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排序方式: 共有536条查询结果,搜索用时 93 毫秒
531.
532.
Vizuete M Gómez-Escalonilla MJ Fierro JL Yudasaka M Iijima S Vartanian M Iehl J Nierengarten JF Langa F 《Chemical communications (Cambridge, England)》2011,47(48):12771-12773
A soluble hybrid nanomaterial that combines fullerenes and carbon nanohorns (CNHs) has been prepared and fully characterized. Electrochemical investigations revealed that the CNHs modify the electron accepting ability of C(60) in the hybrid material. 相似文献
533.
Akira Ito Tomoki Aoyama Junichi Tajino Momoko Nagai Shoki Yamaguchi Hirotaka Iijima Xiangkai Zhang Haruhiko Akiyama Hiroshi Kuroki 《Physical Therapy Research》2014,17(1):14-21
Aim: To facilitate establishment of an effective thermotherapy for osteoarthritis (OA), we investigated the effects of the thermal environment on articular chondrocyte metabolism in vitro. Methods: Chondrocytes were isolated from porcine knee joints, and cultured at 32°C, 37°C and 41°C. Cell proliferation and viability were assessed at Days 2, 4 and 8. In addition, TdT-mediated dUTP nick end labeling (TUNEL) assay was performed at Day 3 to determine the proportion of apoptotic chondrocytes. Analysis of genes specific for factors related to the cartilage extracellular matrix (ECM), cartilage destruction, and cartilage protection was performed at Day 2. Furthermore, evaluation of heat stress tolerance, and heat shock protein 70 (HSP70) mRNA expression and protein synthesis was performed at Day 2 and 3, respectively. Results: Cell proliferation was more at 37°C than at 32°C and 41°C. Cell viability and the number of TUNEL-positive cells were not affected until Day 8 and 3, respectively. The expression of the ECM-related genes was up-regulated at higher temperature. The expression of MMP13, a type II collagen destructive enzyme, and that of TIMP1 and TIMP2, which are MMP inhibitors, were up-regulated at higher temperatures. Finally, the chondrocytes cultured at 41°C may acquire heat stress tolerance, in part, due to the up-regulation of HSP70, and may inhibit apoptosis induced by various stresses, which is observed in OA. Conclusions: The thermal environment affects articular chondrocyte metabolism, and a heat stimulus of approximately 41°C could enhance chondrocyte anabolism and induce heat stress tolerance. 相似文献
534.
The diffusion coefficient of nickel in cold-worked carbon steel was determined with the diffusion couple method in the temperature range between 320 and 450 °C. Diffusion couple was prepared by electro-less nickel plating on the surface of a 20% cold-worked carbon steel. The growth in width of the interdiffusion zone was proportional to the square root of diffusion time to 12,000 h. The diffusion coefficient (DNi) of nickel in cold-worked carbon steel was determined by extrapolating the concentration-dependent interdiffusion coefficient to 0% of nickel. The temperature dependence of DNi is expressed by DNi = (4.5 + 5.7/?2.5) × 10?11 exp (?146 ± 4 kJ mol?1/RT) m2s?1. The value of DNi at 320 °C is four orders of magnitude higher than the lattice diffusion coefficient of nickel in iron. The activation energy 146 kJ mol?1 is 54% of the activation energy 270.4 kJ mol?1 for lattice diffusion of nickel in the ferromagnetic state iron. 相似文献
535.
Choi SK Olsen SL Adachi I Aihara H Aulchenko V Aushev T Aziz T Bakich AM Balagura V Bedny I Bitenc U Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Dalseno J Danilov M Dash M Eidelman S Gabyshev N Golob B Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou WS Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Kah DH Kang JH Katayama N Kawai H Kawasaki T Kichimi H Kim HO Kim SK Kim YJ 《Physical review letters》2008,100(14):142001
A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider. 相似文献
536.
Nakahama Y Sumisawa K Adachi I Aihara H Aushev T Bakich AM Balagura V Barberio E Bedny I Belous K Bitenc U Bondar A Bozek A Bracko M Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Cho IS Choi Y Dalseno J Dash M Drutskoy A Eidelman S Gabyshev N Golob B Ha H Haba J Hara K Hara T Hayasaka K Hazumi M Heffernan D Hoshi Y Hsiung YB Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Kah DH Kaji H Kang JH Katayama N Kawai H Kawasaki T Kichimi H Kim HJ Kim HO 《Physical review letters》2008,100(12):121601
We report a measurement of the CP-violating parameters in B;{0}-->K_{S}{0}K_{S}{0} decays based on a data sample of 657x10{6} BB[over ] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e;{+}e{-} collider. In this Letter, one neutral B meson is fully reconstructed in the B;{0}-->K_{S}{0}K_{S}{0} decay mode, and the flavor of the accompanying B meson is identified by its decay products. The CP-violating parameters are measured from the asymmetry in the distributions of the proper-time interval between the two B decays: S_K_{S}{0}K_{S}{0}}=-0.38_{-0.77}{+0.69}(stat)+/-0.09(syst) and A_{K_{S}{0}K_{S}{0}}=-0.38+/-0.38(stat)+/-0.05(syst). 相似文献