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241.
Online automatic transient isotachophoresis concentration of DNA-aptamer and its thrombin complex by using one kind of pseudo-terminating electrolyte buffer in a cross-channel poly(methyl methacrylate) microchip is reported. Sample injection, transient concentration and separation were done continuously and controlled by a sequential voltage switching program, time-consuming steps and complicated chip design were not required. Peak resolution between DNA-aptamer and its thrombin complex was influenced by this novel pseudo-terminating electrolyte buffer, which was prepared by the addition of chemical component with slow mobility into the same buffer as leading electrolyte buffer. 1100-fold signal enhancement of thrombin complex was achieved by this transient isotachophoresis on a standard cross-form microchip. The concentration effect or standing time of transient isotachophoresis was proved to be influenced by the concentration of leading electrolyte ion and the concentration of pseudo-terminating electrolyte buffer ion (glycine). The transient concentration was followed by on-chip nondenaturing gel electrophoresis in methylcellulose solution for the size-based separation. The detection limit, taken as the lowest thrombin concentration at threefold S/N, was determined to be 0.5 amol in mass by this method. 相似文献
242.
Iwabuchi M Nakao M Adachi I Arinstein K Aulchenko V Aushev T Bakich AM Balagura V Barberio E Bay A Belous K Bhardwaj V Bitenc U Bozek A Bracko M Browder TE Chen A Chen WT Cheon BG Cho IS Choi Y Dalseno J Dash M Drutskoy A Eidelman S Fujikawa M Gabyshev N Ha H Haba J Hayasaka K Hazumi M Heffernan D Horii Y Hoshi Y Hou WS Hyun HJ Inami K Ishikawa A Ishino H Itoh R Iwasaki M Kah DH Kaji H Kang JH Kawai H Kawasaki T Kichimi H Kim HJ Kim HO Kim YI Kim YJ Kinoshita K Korpar S Krizan P Krokovny P 《Physical review letters》2008,101(4):041601
We report on a search for the doubly Cabibbo suppressed decay B+-->D*+pi0, based on a data sample of 657x10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no significant signal and set an upper limit of B(B+-->D*+pi0)<3.6x10(-6) at the 90% confidence level. This limit can be used to constrain the ratio between suppressed and favored B-->D*pi decay amplitudes, r<0.051, at the 90% confidence level. 相似文献
243.
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
244.
Natsuo Nagamura Prof. Hisahiro Sasabe Hiroki Sato Nozomi Ito Shoki Abe Dr. Yoshihito Sukegawa Prof. Daisuke Yokoyama Prof. Hironori Kaji Prof. Junji Kido 《Chemistry (Weinheim an der Bergstrasse, Germany)》2023,29(1):e202202636
Using a tailored high triplet energy hole transport layer (HTL) is a suitable way to improve the efficiency and extend the lifetime of organic light-emitting devices (OLEDs), which can use all molecular excitons of singlets and triplets. In this study, dibenzofuran (DBF)-end-capped and spirobifluorene (SBF) core-based HTLs referred as TDBFSBF1 and TDBFSBF2 were effectively developed. TDBFSBF1 exhibited a high glass transition temperature of 178 °C and triplet energy of 2.5 eV. Moreover, a high external quantum efficiency of 22.0 %, long operational lifetime at 50 % of the initial luminance of 89,000 h, and low driving voltage at 1000 cd m−2 of 2.95 V were achieved in green phosphorescent OLEDs using TDBFSBF1 . Further, a high-hole mobility μh value of 1.9×10−3 cm2 V−1 s−1 was recorded in TDBFSBF2 . A multiscale simulation successfully reproduced the experimental μh values and indicated that the reorganization energy was the primary factor in determining the mobility differences among these SBF core based HTLs. 相似文献