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41.
Qamrul Hasan Ansari Siegfried Schaible Jen-Chih Yao 《Journal of Global Optimization》2002,22(1-4):3-16
In this paper, we introduce the system of generalized vector equilibrium problems which includes as special cases the system of generalized implicit vector variational inequality problems, the system of generalized vector variational and variational-like inequality problems and the system of vector equilibrium problems. By using a maximal element theorem, we establish existence results for a solution of these systems. As an application, we derive existence results for a solution of a more general Nash equilibrium problem for vector-valued functions. 相似文献
42.
Javad Mashreghi Julian Ransford Thomas Ransford 《Journal of Functional Analysis》2018,274(11):3254-3262
We show that every linear functional on the Dirichlet space that is non-zero on nowhere-vanishing functions is necessarily a multiple of a point evaluation. Continuity of the functional is not assumed. As an application, we obtain a characterization of weighted composition operators on the Dirichlet space as being exactly those linear maps that send nowhere-vanishing functions to nowhere-vanishing functions.We also investigate possible extensions to weighted Dirichlet spaces with superharmonic weights. As part of our investigation, we are led to determine which of these spaces contain functions that map the unit disk onto the whole complex plane. 相似文献
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45.
L.-C. Ceng S. Al-Homidan Q.H. Ansari J.-C. Yao 《Journal of Computational and Applied Mathematics》2009
In this paper, we propose an iterative scheme for finding a common element of the set of solutions of an equilibrium problem and the set of fixed points of a strict pseudo-contraction mapping in the setting of real Hilbert spaces. We establish some weak and strong convergence theorems of the sequences generated by our proposed scheme. Our results combine the ideas of Marino and Xu’s result [G. Marino, H.K. Xu, Weak and strong convergence theorems for strict pseudo-contractions in Hilbert spaces, J. Math. Anal. Appl. 329 (2007) 336–346], and Takahashi and Takahashi’s result [S. Takahashi, W. Takahashi, Viscosity approximation methods for equilibrium problems and fixed point problems in Hilbert spaces, J. Math. Anal. Appl. 331 (2007) 506–515]. In particular, necessary and sufficient conditions for strong convergence of our iterative scheme are obtained. 相似文献
46.
Seyyed Javad Sabounchei Khadijeh Badpa Mehdi Bayat Roya Karamian Fatemeh Ghasemlou Robert W. Gable Parviz Gohari Derakhshandeh Kristof Van Hecke 《应用有机金属化学》2019,33(3)
The reaction of α‐keto‐stabilized diphosphine ylides [Ph2P(CH2)nPPh2═C(H)C(O)C6H4‐p‐CN] (n = 1 (Y1); n = 2 (Y2)) with dibromo(1,5‐cyclooctadiene) palladium(II)/platinum(II) complexes, [Pd/PtBr2(cod)], in equimolar ratio gave the new cyclometalated Pd(II) and Pt(II) complexes [Br2Pd(κ2‐Y1)] ( 1 ), [Br2Pt(κ2‐Y1)] ( 2 ), [Br2Pd(κ2‐Y2)] ( 3 ) and [Br2Pt(κ2‐Y2)] ( 4 ). These compounds were screened in a search for novel antibacterial agents and characterized successfully using Fourier transfer infrared and NMR (1H, 13C and 31P) spectroscopic methods. Also, the structures of complexes 1 and 2 were characterized using X‐ray crystallography. The results showed that the P,C‐chelated complexes 1 and 2 have structures consisting of five‐membered rings, while 3 and 4 have six‐membered rings, formed by coordination of the ligand through the phosphine group and the ylidic carbon atom to the metal centre. Also, a theoretical study of the structures of complexes 1 – 4 was conducted at the BP86/def2‐SVP level of theory. The nature of metal–ligand bonds in the complexes was investigated using energy decomposition analyses (EDA) and extended transition state combined with natural orbitals for chemical valence analyses. The results of EDA confirmed that the main portions of ΔEint, about 57–58%, in the complexes are allocated to ΔEelstat. 相似文献
47.
Saeed Bahadorikhalili Samira Ansari Haleh Hamedifar Leila Ma'mani Mohsen Babaei Rahim Eqra Mohammad Mahdavi 《应用有机金属化学》2019,33(4)
In this paper, a novel catalyst is introduced based on the immobilization of palladium on modified magnetic graphene oxide nanoparticles. The catalyst is characterized by several methods, including transmission electron microscopy, scanning electron microscopy, X‐ray fluorescence, vibrating‐sample magnetometer, Fourier transform‐infrared and dynamic light scattering (DLS) analysis. The activity of the catalyst was investigated in the synthesis of 4(3H)‐quinazolinones via Pd‐catalyzed carbonylation‐cyclization of N‐(2‐bromoaryl) benzimidamides by Mo (CO)6. The Mo (CO)6 is used as a carbon monoxide source for performing the reaction under mild conditions. The catalyst showed good reusability, and no change in activity was observed after 10 cycles of recovery. 相似文献
48.
Novel functionalized graphene adsorbent was prepared and characterized using different techniques. The prepared adsorbent was applied for the removal of cadmium ions from aqueous solution. A response surface methodology was used to evaluate the simple and combined effects of the various parameters, including adsorbent dosage, pH, and initial concentration. Under the optimal conditions, the cadmium removal performance of 70% was achieved. A good agreement between experimental and predicted data in this study was observed. The experimental results revealed of cadmium adsorption with high linearity follow Langmuir isotherm model with maximum adsorption capacity of 502 mg g?1, and the adsorption data fitted well into pseudo‐second order model. Thermodynamic studies showed that adsorption process has exothermic and spontaneous nature. The recommended optimum conditions are: cadmium concentration of 970 mg L?1, adsorbent dosage of 1 g L?1, pH of 6.18, and T = 25 °C. The magnetic recovery of the adsorbent was performed using a magnetic surfactant to form a noncovalent magnetic functionalized graphene. After magnetic recovery of the adsorbent both components (adsorbent and magnetic surfactant) were recycled by tuning the surface charges through changing the pH of the solution. Desorption behavior studied using HNO3 solution indicated that the adsorbent had the potential for reusability. 相似文献
49.
We present novel inorganic–organic hybrid catalyst to accomplish domino multi‐component reaction (MCR) for synthesis of 3‐amino‐2′‐oxospiro[benzo[c]pyrano[3,2‐a]phenazine‐1,3′‐indoline]‐2‐carbonitrile/carboxylate derivatives. This methodology offers remarkable development by easy production of H3PMo12O40/Hyd‐SBA‐15 in regard to solving the problem of using harsh catalysts, also it demonstrates to be impressive and environmentally friendly in term of low reaction times and high yields. 相似文献
50.
Synthesis,characterization, dielectric and rectification properties of PANI/Nd2O3:Al2O3 nanocomposites 下载免费PDF全文
Juhi Nishat Ansari Syed Khasim Ameena Parveen Omar A Al‐Hartomy Ziad Khattari Nacer Badi Aashis. S. Roy 《先进技术聚合物》2016,27(8):1064-1071
Polyaniline–Nd2O3:Al2O3 nanocomposites were prepared by in situ oxidative polymerization method using different weight percentages of oxide powders. The prepared nanocomposites were characterized by Fourier transform infrared spectroscopy and X‐ray diffraction for molecular and crystal structures. Scanning electron microscopy and transmission electron microscopy images show the tubular structure of polyaniline nanocomposite with embedded metal oxides. The electrical conductivity of the nanocomposites increases with increase in temperature as well as with concentration of Nd2O3:Al2O3 particles in polyaniline. This is because of the hopping of charge polarons and extended chain length of the nanocomposites as evidenced by the negative thermal coefficient (NTC) characteristic. A high NTC value of 2.67 was found in nanocomposites with 15 wt% of oxide particles. These nanocomposites show low dielectric constant and dielectric loss; the electrical conductivity is higher than 0.3 S/cm as confirmed by Cole–Cole plot that indicates a decrease in both grain resistance and bulk resistance of the nanocomposites. The current–voltage and capacitance–voltage measurements were also carried out. The carrier mobility μ values of pure polyaniline and nanocomposites were found to be 4.27 × 10?3 and 1.45 × 10–2 H.M?1, respectively. A significant enhancement in carrier mobility was observed in comparison with the literature. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献