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961.
The 3-D Look-Locker (LL) imaging method has been shown to be a highly efficient and accurate method for the volumetric mapping of the spin lattice relaxation time T(1). However, conventional 3-D LL imaging schemes are typically limited to small tip angle RF pulses (5 degrees ), thereby improving the SNR and the accuracy of the method. In phantom studies, a mean T(1) measurement accuracy of less than 2% (0.2-3.1%) using a tip angle of 10 degrees was obtained for a range of T(1) from approximately 300 to 1,700 ms with a measurement time increase of only 15%. This accuracy compares favorably with the conventional 3-D LL method that provided an accuracy between 2.2% and 7.3% using a 5 degrees flip angle. 相似文献
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Undoped Layered Perovskite Oxynitride Li2LaTa2O6N for Photocatalytic CO2 Reduction with Visible Light
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Takayoshi Oshima Tom Ichibha Ken Sinkou Qin Kanemichi Muraoka Dr. Junie Jhon M. Vequizo Keisuke Hibino Ryo Kuriki Dr. Shunsuke Yamashita Prof. Dr. Kenta Hongo Dr. Tomoki Uchiyama Prof. Dr. Kotaro Fujii Dr. Daling Lu Prof. Dr. Ryo Maezono Prof. Dr. Akira Yamakata Prof. Dr. Hideki Kato Dr. Koji Kimoto Prof. Dr. Masatomo Yashima Prof. Dr. Yoshiharu Uchimoto Prof. Dr. Masato Kakihana Prof. Dr. Osamu Ishitani Prof. Dr. Hiroshi Kageyama Prof. Dr. Kazuhiko Maeda 《Angewandte Chemie (International ed. in English)》2018,57(27):8154-8158
Oxynitrides are promising visible‐light‐responsive photocatalysts, but their structures are almost confined with three‐dimensional (3D) structures such as perovskites. A phase‐pure Li2LaTa2O6N with a layered perovskite structure was successfully prepared by thermal ammonolysis of a lithium‐rich oxide precursor. Li2LaTa2O6N exhibited high crystallinity and visible‐light absorption up to 500 nm. As opposed to well‐known 3D oxynitride perovskites, Li2LaTa2O6N supported by a binuclear RuII complex was capable of stably and selectively converting CO2 into formate under visible light (λ>400 nm). Transient absorption spectroscopy indicated that, as compared to 3D oxynitrides, Li2LaTa2O6N possesses a lower density of mid‐gap states that work as recombination centers of photogenerated electron/hole pairs, but a higher density of reactive electrons, which is responsible for the higher photocatalytic performance of this layered oxynitride. 相似文献
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For primes we obtain a simple formula for p(N) (mod ) as a weighted sum over -square affine partitions of N. When {3,5,7,11}, the weights are explicit divisor functions. The Ramanujan congruences modulo 5, 7, 11, 25, 49, and 121 follow immediately from these formulae. 相似文献
968.
Amorphous As2Se1Te2 (a-As2Se1Te2) films, into which Cu or Cd ions were doped by thermal diffusion below the glass transition temperature exhibited the increase of conductivity by several orders of magnitude. In addition, these samples exhibited enhanced photoconductivity and the activation type conduction. From the measurements of the thermoelectric power, it was found that Cu doped samples were p-type and Cd doped samples were n-type. The impurities was also studied by SIMS. 相似文献
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Petradza M Akerlof C Chapman J Errede D Ken MT Meyer DI Neal H Nitz D Thun R Tschirhart R Abachi S Derrick M Kooijman P Price LE Repond J Sugano K Cork B Blockus D Brabson B Brom JM Jung C Ogren H Rust DR Baringer P Bylsma BG DeBonte R Koltick D Low EH McIlwain RL Miller DH Ng CR Shibata EI 《Physical review D: Particles and fields》1990,42(7):2180-2186
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