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971.
Ju‐You Lu Hong Wan Jianwei Zhang Zhixuan Wang Yang Li Yongmei Du Chunying Li Prof. Zhao‐Tie Liu Prof. Zhong‐Wen Liu Prof. Jian Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17542-17546
A palladium‐catalyzed direct C‐arylation reaction of readily available cage carboranyllithium reagents with aryl halides has been developed for the first time. This method is applicable to a wide range of aryl halide substrates including aryl iodides, aryl bromides, and heteroaromatic halides. 相似文献
972.
973.
Tetrachlorosilane was found to be a mild as well as selective catalyst for dithioacetalization of the carbonyl compounds. 相似文献
974.
This paper proposes a new formulation of regularized meshless method (RMM), which differs from the traditional RMM in that the traditional formulation generates the diagonal elements of influence matrix via null-field integral equations, while our new one directly employs the boundary integral equations at the domain point to evaluate the diagonal elements. We test the present RMM formulation to two-dimensional anisotropic potential problems in finite and infinite domains in comparison with the traditional RMM. Numerical results show that the present RMM sharply outperforms the traditional RMM in the solution of interior problems, while the latter is clearly superior for exterior problems. A rigorous theoretical analysis of circular domain case also corroborates such numerical experiment observations and is provided in the appendix of this paper. 相似文献
975.
Zhifang Xi Wei Bie Wei Chen Dong Liu Leen van Ofwegen Peter Proksch Wenhan Lin 《Helvetica chimica acta》2013,96(12):2218-2227
Six new biscembranoids, namely, sarcophytolides G–L ( 1 – 6 , resp.), together with six known analogs, were isolated from a marine soft coral Sarcophyton elegans. The structures of the new compounds were established on the basis of 1D‐ and 2D‐NMR (COSY, HSQC, HMBC, and NOESY) spectroscopic analysis together with the aid of MS, CD, and IR data. The unusual isobiscembranoid sarcophytolide G ( 1 ) was found for the first time in the genus Sarcophyton. 相似文献
976.
Sheng Yang Antonio Gaetano Ricciardulli Dr. Shaohua Liu Dr. Renhao Dong Dr. Martin R. Lohe Alfons Becker Marco A. Squillaci Prof. Paolo Samorì Prof. Klaus Müllen Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2017,56(23):6669-6675
To bridge the gap between laboratory-scale studies and commercial applications, mass production of high quality graphene is essential. A scalable exfoliation strategy towards the production of graphene sheets is presented that has excellent yield (ca. 75 %, 1–3 layers), low defect density (a C/O ratio of 21.2), great solution-processability, and outstanding electronic properties (a hole mobility of 430 cm2 V−1 s−1). By applying alternating currents, dual exfoliation at both graphite electrodes enables a high production rate exceeding 20 g h−1 in laboratory tests. As a cathode material for lithium storage, graphene-wrapped LiFePO4 particles deliver a high capacity of 167 mAh g−1 at 1 C rate after 500 cycles. 相似文献
977.
A feasible proposal is explored to remotely perform a family of multi-qubit controlled-phase gates (MQCPG), with the aid of entanglement transfer and quantum repeater. To remotely realize the gates, some local transformations, including single-qubit rotating operation, controlled-NOT gate and quantum phase gate, are employed during the realization. It turns out that MQCPG can be implemented among separate spatially agents with nearly unit fidelity and success probability. Besides, required classical information consumption of the proposed scenario is worked out. Furthermore, some attractive issues are discussed including the feature of present proposal and the experimental feasibility based on current technologies. Remarkably, it is revealed that our proposal essentially accesses to several nontrivial features lying in breaking through the limitation that error probability scales exponentially with the length of the channel in the course of the realization of the gates, and well compatibility with today’s experimental technologies. 相似文献
978.
H. M. Noor ul Huda Khan Asghar Yi Tan Shuang Shi Dachuan Jiang Shiqiang Qin Jiao Liao Shutao Wen Wei Dong Yao Liu 《Applied Physics A: Materials Science & Processing》2014,115(3):753-757
Small amounts of multicrystalline silicon were melted in an electron beam furnace in different experimental conditions in order to investigate the oxygen evaporation behavior during the electron beam melting (EBM) process. The oxygen content level before and after EBM was determined by secondary ion mass spectroscopy. The oxygen content was reduced from 6.177 to 1.629 ppmw when silicon was melted completely at 15 kW with removal efficiency up to 73.6 %. After that, it decreased continually to <0.0517 ppmw when the refining time exceeded 600 s with a removal efficiency of more than 99.08 %. During the melting process, the evaporation rate of silicon is 1.10 × 10?5 kg/s. The loss of silicon could be reduced up to 1.7 % during oxygen removal process to a desirable figure, indicating EBM is an effective method to remove oxygen from silicon and decrease the loss of silicon. 相似文献
979.
The highly enantioselective Friedel–Crafts reaction of indoles with trifluoropyruvate catalyzed by a C3-symmetric cinchonine-squaramide is reported. A wide variety of trifluoromethylated indole derivatives were obtained in high yields and with excellent enantioselectivities (99% and up to >99% ee). Moreover the C3 catalyst can be easily recovered and was used five times. 相似文献
980.
Multilayered gels play an important role in biomedical engineering as drug delivery vehicles, replacement tissues and bio-mimetic substrates for cell cultures. It has been established that the gel elasticity strongly influences the intended functionalities. In view of this, second-order elastic solutions for the stresses and displacements in cylindrical multilayered hydrogels subjected to various dilatation profiles are developed in this paper. The results emphasize the importance of nonlinearity in gel mechanics, and suggest the possibility of a rational selection of layer elasticities, layer thicknesses and dilatation profiles for improved mechanical responses such as maximum/minimum swelling and multiaxial stress states. 相似文献