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981.
Chunbo Lai Chanjuan Xi Yuping Feng 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):449-455
Alkyllithium reacts with chlorophosphate to generate the α -lithio- alkylidenediphosphonate, which further reacts with halogen reagents to afford corresponding α -halogenated alkylidenediphosphonates. 相似文献
982.
983.
Philip J. Parsons Stephen P.G. RushtonRaghava R. Panta Adrian J. MurrayMartyn P. Coles Jason Lai 《Tetrahedron》2011,67(52):10267-10273
New approaches to the synthesis of kainic acid and its analogues are presented. Two distinctly different approaches are described; the former utilised an intermolecular nitrile oxide addition to a homochiral substrate to furnish epikainate models and the second utilised amino acid chemistry to secure kainic acid. 相似文献
984.
985.
In this paper we give a formula for the number of representations of some square-free integers by certain ternary quadratic
forms and estimate the lower bound of the 2-power appearing in this number.
Supported by NSFC and RFDP. 相似文献
986.
A series of conjugated/non-conjugated copolymers and their corresponding oligomers were prepared and their optical and physical properties were investigated for understanding the merit of blocking the conjugated chromophores with non-conjugated spacers. It was found that compared to the oligomers, copolymers have the advantages of amorphous nature, high thermal stability, and good thin film processability without sacrificing the quantum efficiency and purity of the emission color. Furthermore, based on the optical data of these copolymers and oligomers, the conjugation length of the polyoctylthiophene was estimated to be extended over 23-31 octylthiophene rings. 相似文献
987.
988.
Ranbo Yu Zhenmin Li Dan Wang Xiaoyong Lai Chaojian Xing Xianran Xing 《Solid State Sciences》2009,11(12):2056-2059
By using simple mixed solvents, the morphologies of hematite (α-Fe2O3) particles could be manipulated, and the spherical, mulberry-like, nanospherical and top-like products could be controllably obtained. The as-obtained products were characterized by X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometer. The results indicated that the morphology manipulation could be achieved by systematically adjusting the polarity of the mixed solvent via the ratio control. And the magnetic properties of the products were critically affected by their grain size and assembly morphologies. 相似文献
989.
990.
A feasible scheme for constructing quantum logic gates is proposed on the basis of quantum switches in cavity QED. It is shown that the light field which is fed into the cavity due to the passage of an atom in a certain state can be used to manipulate the conditioned quantum logical gate. In our scheme, the quantum information is encoded in the states of Rydberg atoms and the cavity mode is not used as logical qubits or as a communicating “bus”; thus, the effect of atomic spontaneous emission can be neglected and the strict requirements for the cavity can be relaxed. 相似文献