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991.
Da Yan He Zhan Jiang Li Zhong Jun Li Yun Qi Liu Dong Xu Qiu Meng Shen Cai 《合成通讯》2013,43(18):2653-2658
Cabohydrates reacting with acetone in the presence of molecular sieve and p—toluene sulfonic acid provided a simple, convenient, high yield and good selective process for preparation of isopropylidene carbohydrates. 相似文献
992.
Yi Song Jiang-Li Ni Zhang-Yin Wang Yan Lu Lian-Fang Han 《International Journal of Theoretical Physics》2017,56(10):3175-3187
We present a new scheme for deterministically realizing the mutual interchange of quantum information between two distant parties via selected quantum states as the shared entangled resource. We first show the symmetric bidirectional remote state preparation (BRSP), where two single-qubit quantum states will be simultaneously exchanged in a deterministic manner provided that each of the users performs single-qubit von Neumann measurements with proper measurement bases as well as appropriate unitary operations, depending essentially on the outcomes of the prior measurements. Then we consider to extend the symmetric protocol to an asymmetric case, in which BRSP of a general single-qubit state and an arbitrary two-qubit state is investigated successfully. The necessary quantum operations and the employed quantum resources are feasible according to the present technology, resulting in that this protocol may be realizable in the realm of current physical experiment. 相似文献
993.
Lie Shen Du Xu Yukun Jian Wenlian Qiu Qipeng Guo 《Journal of Macromolecular Science: Physics》2017,56(4):254-261
The mutual diffusion process and interphase development taking place at the interface between disks of polystyrene (PS) and carbon black filled polystyrene (CB-PS) in the molten state were investigated by a small-amplitude, oscillatory shear, rheological technique. The rheological method was employed to probe the thermorheological complexity of these polymer disks. It was found that the dynamic complex shear modulus, G*(t), increased with the time of contact in two time regimes at a fixed frequency. The time of transition between the two regimes was observed to be close to the time needed for the transition from the Rouse mode to the reptation mode. The results showed that the content of the carbon black and the temperature affected the slope of the G*(t) – t curve. Scanning electron microscopy revealed the interface disappeared when the diffusion process was complete. 相似文献
994.
995.
Simple scaling laws for the design parameters of plasma wakefield accelerators were obtained using a theoretical model, which were confirmed via particle simulation studies. It was found that the acceleration length was given by Δx=0.804λp/(1−βg), where λp is the plasma wavelength and βgc the propagation velocity of the ion cavity. The acceleration energy can also be given by ΔE=(γm−1)mc2=2.645mc2/(1−βg), where m is the electron rest mass. As expected, the acceleration length and energy increase drastically as βg approached unity. These simple scaling laws can be very instrumental in the design of better-performing plasma wakefield accelerators. 相似文献
996.
Using the classical Mie scattering theory,we compute the energy density of an arbitrary partial wave(e.g.,the nth order) and then determine that the interaction between an incident planar wave and a sphere of radius a is the one between the sphere and those partial waves the order of which satisfies n≤ka.We also provide a simple expression to describe the diffracted wave in which the angle-dependent functions are employed.The difference between the accurate and the approximate expressions is demonstrated by numerical calculation. 相似文献
997.
Indothiazinone is a natural 3-acylindole alkaloid, isolated from a culture of myxobacterial strain. It was found to possess antibacterial activity against yeast and filamentous fungi. Indothiazinone is also structurally related with a mammalian endogenous aryl hydrocarbon receptor ligand, (2-(1′H-indole-3′-carbonyl)thiazol-4-carboxylic acid methyl ester (ITE). In this article, the synthesis of indothiazinone has been disclosed for the first time. Key feature includes direct and selective 3-acylation of indole in the presence of Lewis acid. In addition, an efficient preparation of N-substituted indothiazinone derivatives has been demonstrated. 相似文献
998.
Liu Changqi Huo Dongying Yang Xu Ma Zhanwen Zhou Jianjin Han Chao Bai Xiaohou Wu Kang Zhang Yu Wang Junrun Yao Zeen Wei Zheng 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):1091-1099
Journal of Radioanalytical and Nuclear Chemistry - A Frisch-grid Ionization Chamber (FGIC) for the measurement of low activity of alpha-particle emitters has been built. The design and performance... 相似文献
999.
Silylated 2,4-enynyl amides can be synthesized by the reaction of 3-(trimethylsilyl)-2-propynylidenetriphenylarsorane, generated in situ from the corresponding arsonium salt and n-butyllithium, with α-bromoacetamides in 40–59% yields (two steps) and with high stereoselectivity. 相似文献