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941.
942.
《Applied Mathematical Modelling》2014,38(5-6):1685-1697
This paper is concerned with the problem of output feedback stabilization for a class of discrete-time systems with sector nonlinearities and imperfect measurements. A unified control law model is proposed to take the network-induced delay, random packet dropout and measurement quantization into consideration simultaneously. By choosing appropriate Lyapunov functional, a new stability condition, which is dependent on multiple network status, is established for the resulting closed-loop system. Based on the result, a design criterion for the static output feedback controller is formulated in the form of nonconvex matrix inequalities, and the cone complementary linearization (CCL) procedure is exploited to solve the nonconvex feasibility problem. Incidentally, a less conservative synthesis method is also developed for the state feedback stabilization purpose. Finally, two illustrative examples are provided to illustrate the effectiveness and applicability of the proposed design method. 相似文献
943.
Abstract The main purpose of this article is to prove a collection of new nxea point theorems for (ws)-compact and so-called 1-set weakly contractive operators under Leray- Schauder boundary condition. We also introduce the concept of semi-closed operator at the origin and obtain a series of new fixed point theorems for such class of operators. As consequences, we get new fixed point existence for (ws)-compact (in particular nonexpansive) self mappings unbounded closed convex subset of Banach spaces. The main condition in our results is formulated in terms of axiomatic measures of weak noncompactness. Later on, we give an application to generalized Hammerstein type integral equations. 相似文献
944.
In this paper, using the context of complete partial metric spaces, some common fixed point results of maps that satisfy the generalized(φ, ψ)-weak contractive conditions are obtained. Our results generalize, extend, unify, enrich and complement many existing results in the literature. Example are given showing the validaty of our results. 相似文献
945.
In the present work, the blend of poly(butylene succinate) (PBS) and bisphenol A (BPA) was prepared by solution mixing, and the intermolecular interactions between the two components were characterized by a combination of nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR). The results showed that intermolecular hydrogen-bonding forms between the carbonyl group of PBS and phenol hydroxyl of BPA. With the increase of BPA content, more hydrogen bonds were formed. The effect of hydrogen bonding on the crystallization behavior of PBS was investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The results showed that the overall isothermal crystallization kinetics and the spherulite growth rate of PBS decrease with the increase of BPA content, while the PBS spherulite size increases with BPA content. 相似文献
946.
A new Cd(II) complex [Cd(C12H6OaN2)(Phen)ffH2O)]'3H2O with 2,2"-bipyridine- 3,3"-dicarboxylic acid as a ligand has been synthesized. Crystal data for the title complex are as follows: monoclinic, space group P2dn, a = 12.8458(5), b = 17.9131(7), c = 15.2960(6) A, β = 111.7430(10)°, V = 3269.3(2) A3, Dc = 1.581 g/cm3, Z = 4,/a(MoKa) = 0.731 mm-1, F(000) = 1580, the R = 0.0244 and wR = 0.0605. In the title complex, the central Cd(ll) ion is located in a distorted octahedral coordination environment. The electrochemical and fluorescent properties of the title complex were studied. The results show that the electron transfer of the title complex is irreversible in the electrode reaction and it has a broad emission peak in the range of 470-508 nm with the excitation wavelength of 488 nm. 相似文献
947.
The compound N-phenyl-N-[(o-nitrophenylacetyl)oxy]benzamide (C21HI6N2Os, Mr = 376) has been synthesized by the reaction of N-hydroxy-N-phenylbenzamide with 2-(2-nitro- phenyl)acetyl chloride in dichlorom-ethane and its structure Was characterized by 1H NMR, 13C NMR, IR, H RMS(ESI) and single-crystal X-ray diffraction. The crystal of the title compound belongs to monoclinic, space group C2/c with a = 32.30(2), b = 8.400(5), c = 15.099(9) A, fl = 114.256(10)°, V = 3735(4) A3, Z = 8, D, = 1.339 g/cm3, F(000) = 1568, p = 0.097 mm-1, the final R = 0.0506 and wR = 0.1176 for 2318 observed reflections (1 〉 2a(/)). The title molecule contains three branched chains with its center placed at the midpoint of N. The phenyl ring (C(1)'-C(6)) makes a dihedral angle of 70.3(1)° with the phenyl ring (C(10)-C(15)) of benzoyl group, and 14.3(1)° with the phenyl ring (C(16) - C(21)), Hydrogen bonds C(5)-H(5)...O(1) and C(12)-H(12)...O(3) together with it-Jr stacking interactions contribute to the stability of the structure. 相似文献
948.
A new Co(ll) polymer [Co(tdc)(l,4-bimb)]n 1 (H2tdc = thiophene-2,3-dicarboxy- lic acid, 1,4-bimb -- 1,4-bis(imidazol-1 '-yl)butane) was synthesized under hydrothermal conditions The compound crystallizes in the monoclinic system, space group C2/c with a = 15.643(9), b = 8.839(5), c=12.952(7) A, β = 105.964(6)°, V= 1721.8(16) A3, Z = 4, Mr = 419.32, Dc= 1.618 Mg/m3,μ = 1.149 mm-1, F(000) = 860, the final R = 0.0243 and wR =0.0613 for 1460 observed reflections with I 〉 2σ(I). The compound presents a three-dimensional (3D) network extended by both tdc2- anions and 1,4-bimb ligands in which the tdc2- anions employ a chelating coordination mode. From the topology point of view, the structure could be described as a 3D 4-connected 65.8 CdSO4-type net. Infrared spectroscopy, elemental analyses, thermogravimetric analysis and powder X-ray diffraction properties of 1 are also investigated. 相似文献
949.
Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is one of the most significant targets for a large family of in- hibitors that may be used as herbicide, bactericide, fungicide, or photosensitizing activator to treat cancer through photodynamic therapy (PDT). Molecular docking and CoMFA were combined in a multistep framework with the ultimate goal of identifying important factor contributing to the activity of PPO inhibitors. As a continuation of the previous research work on the development of new PPO inhibitors, the bioassay results indicated that good PPO in- hibitors were discovered in all of the three chemical series with ICs0 values ranging from 0.010 to 0.061 pmol·L ^-1. Using the crystal structure of tobacco mitochondrial PPO (mtPPO) as template, all the compounds were docked into the enzyme active site. The docking pose of each compound was subsequently used in a receptor-based alignment, leading to the development of a significant CoMFA model with r^2 value of 0.98 and q^2 (cross validation r^2) value of 0.63. This novel multistep framework gives insight into the and it can be extended to other classes of PPO inhibitors. In be particularly applicable in virtual screening procedures. structural characteristics for the binding of inhibitors, addition, the simplicity of the proposed approach may 相似文献
950.
A kind of octanol-modifded silica nanoparticle was fabricated and employed as a framework to form‘‘soggy sand’’electrolyte along with 1-butyl-3-methylimidazolium tetrafluoroborate.‘‘Soggy sand’’and poly(vinylidene fluoride-hexafluoropropylene)composite electrolyte membranes were electrospun for the frst time.The properties of this membrane electrolyte have been evaluated by the mechanical test and electrochemical test.The Young’s modulus increased by 275%from 6.8 MPa to 25.5 MPa and the electrical conductivity increased to 7.6 10à5S/cm at 290.15 K when compared to pristine P(VdF-HFP)membrane electrolyte.The conductivity is 3.1 10à4S/cm at 323.15 K. 相似文献