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911.
This Letter presents an analysis method for a delay-independent absolute stability of time-delay Lur'e systems with sector and slope restrictions. The proposed method is based on the Lyapunov functions with quadratic form of states and nonlinear functions of the systems. Several criteria are derived in terms of linear matrix inequalities (LMIs). A numerical example is illustrated to show the effectiveness of the proposed method. 相似文献
912.
913.
The syntheses of cyclophosphodiesters of 5-C-(hydroxymethyl)-hexoses and hexitols and of 6-C-(hydroxymethyl)-hexoses are reported, along with that of 6-deoxy-gluco-heptose 7-phosphate. These compounds proved to be reasonable substrate mimics and show inhibitory activity against human d-myo-inositol 3-phosphate synthase. 相似文献
914.
915.
916.
917.
Ju‐Myung Song Mohammad Luqman Joon‐Seop Kim Kwanwoo Shin 《Journal of Polymer Science.Polymer Physics》2007,45(9):1045-1052
The mechanical properties and morphology of homoblends of poly(ethyl acrylate‐co‐acrylate) (PEAA) having one ion pair per ionic monomer repeat unit and poly(ethyl acrylate‐co‐itaconate) (PEAITA) having two ion pairs were investigated. It was found that the compositional variation in the ionomer homoblends did not affect the matrix or cluster glass transition temperatures of the two ionomers of the homoblends. It was also observed that the ionomer homoblends showed two ionic plateaus and that the changes in the two ionic moduli were directly related to the relative amounts of the two ionomers. The ionic moduli calculated with the model for filler‐dispersed materials were found to fit the experimental data to a great extent. Therefore, it was suggested that the PEAITA/PEAA ionomer homoblends were filler‐containing composite materials rather than miscible blends. In the X‐ray scattering study, it was observed that the morphology of the ionomer homoblends was not affected by mixing. The results obtained in this work might be useful for the modification of the storage moduli of copolymers in a certain temperature range without the alteration of their processing temperatures. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1045–1052, 2007. 相似文献
918.
Generation of strong stationary optical and mechanical squeezing is proposed for the linear‐and‐quadratic optomechanical system, where two cavity modes induce linear and quadratic optomechanical couplings, respectively. Through the linearization treatment, linearized coupling between cavity mode and mechanical mode and the mechanical parametric amplification process are achievable and controllable by independent driving lasers. Optical and mechanical squeezing are generated following different mechanisms. Optical squeezing works in the strong coupling regime, and mechanical amplification would push the system close to instability threshold, which could deeply improve ponderomotive squeezing even significantly beyond the 3 dB squeezing limit. Mechanical squeezing is generated based on the reservoir engineering method, where parametric amplification induces the squeezing transformation of mechanical mode; and linearized coupling, which operates in the red‐sideband and weak coupling limits, induces the ground‐state cooling of transformed mechanical mode. Finally, the original mechanical mode would be squeezed, which could also exceed 3 dB limit. 相似文献
919.
Xinglong Zhou Zhen Shen Beibei Ma Zhenqiang Xia Yingying Chai Xiaojie Ju Liangyin Chu Ridong Huang Hai Chen Weimin Li Yang He 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(28):9703-9712
Confining polar water molecules to particular geometries demands sophisticated intermolecular interactions, and not many small synthetic molecules have accomplished such a task. Herein, regioisomeric acyclic Janus‐AT nucleosides ( 1 and 2 ), with a self‐complementary fused genetic alphabet and conformationally flexible side chains, have been selectively synthesized. 1 and 2 adopt disparate base‐pair motifs from the π–π stacked hydrophobic base moieties and distinct hydrogen bond (HB) interconnections from the hydrophilic sugar residues, which in turn lead to divergent, intricate intermolecular interaction networks with different capacities to confine water molecules. Under the precise control of the host framework of the N8‐regioisomer, separate ordered single‐file water wires can be locked through special three‐HB clamps into unique inter‐ and intra‐wire geometrical alignments. Localized dynamic synchronized rotations within the fixed framework coordinated by both the host hydroxy groups and guest water molecules were observed in a temperature‐induced reversible single‐crystal‐to‐single‐crystal transition (SCSCT). 相似文献
920.
Five complexes [Co3(Hpmad)6]·(4‐sb)2·(CH3COO)2·(H2O)2 ( 1 ), [Co3(Hpmad)6]·(3‐sb)2·(CH3COO)2·(H2O)0.5 ( 2 ), [Co(Hpmad)2(4‐sb)]n ( 3 ), [Co(Hpmad)2(3‐sb)]n ( 4 ) and {[Co(Hpmad)(SO4)(H2O)2]·H2O}n ( 5 ) [Hpmad is 2‐pyrimidineamidoxime, H2(4‐sb) is 4‐sulfobenzoic acid and H2(3‐sb) is 3‐sulfobenzoic acid], were prepared at room temperature. Complexes 1 – 5 were characterized by elemental analyses, single crystal X‐ray diffractions, powder X‐ray diffractions, infrared spectra, thermogravimetric analyses, fluorescence spectra and magnetic susceptibility measurements. Complexes 1 and 2 possess the linear trinuclear Co2+ structures. Complexes 3 and 4 exhibit similar one‐dimensional (1D) chains. Complex 5 comprises the 1D helical chain. The change of anion in cobalt salt from CH3COO? to Cl? to SO42? leads to the structural evolution from the linear trinuclear Co2+ structure to the 1D chain to the 1D helical chain. Complexes 1 – 5 exhibit the Hpmad‐based emissions. The magnetic properties of 1–5 were also investigated. 相似文献