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51.
We study the Klein-Gordon oscillator in commutative, noncommutative space, and phase space with psudoharmonic potential under magnetic field hence the other choice is studying the Klein-Gordon equation oscillator in the absence of magnetic field. In this work, we obtain energy spectrum and wave function in different situations by NU method so we show our results in tables. 相似文献
52.
This paper proposes a tunable zeroth-order resonator on a composite right/left-handed transmission line consisting of a transversely magnetized ferrite substrate periodically loaded by microstrip inductors. Based on the propagation theory of edge guided modes, the analysis procedure of this structure is introduced. The numerical results demonstrate the tunability of the resonant frequency by changing the DC bias magnetic field applied to the ferrite. In contrast to previous work, the proposed structure is easy to design and fabricate and does not require a chip component. 相似文献
53.
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
54.
We present the notion of weakly metrically regular functions on manifolds. Then, a sufficient condition for a real valued function defined on a complete Riemannian manifold to be weakly metrically regular is obtained, and two optimization problems on Riemannian manifolds are considered. Moreover, we present a generalization of the Palais–Smale condition for lower semicontinuous functions defined on manifolds. Then, we use this notion to obtain necessary conditions of optimality for a general minimization problem on complete Riemannian manifolds. 相似文献
55.
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
56.
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
57.
Mehrnoush Tamimi Majid M. Heravi Masoud Mirzaei Vahideh Zadsirjan Nahid Lotfian Hossein Eshtiagh‐Hosseini 《应用有机金属化学》2019,33(9)
A facile, efficient and eco‐friendly catalytic protocol was developed for the synthesis of medicinally important pyran‐annulated heterocycles via multicomponent reaction (MCR). Cyclocondensation of differently substituted aromatic aldehydes, malononitrile/ethyl cyanoacetate and various β‐dicarbonyl compounds in the presence of Ag3[PMo12O40]?nH2O as heterogeneous catalyst, in EtOH–H2O, afforded diverse pyran‐fused chromene analogues. The merits observed for this approach were it being conducted via MCR, using commercially available or easily accessible starting materials in the presence of a green and easily separable heterogeneous and reusable catalyst, and affording high yields of desired products in very short reaction times with high purity in one‐pot fashion, thus providing a superior alternative approach for the synthesis of pyran‐annulated heterocycles. 相似文献
58.
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
59.
Jafar Akbari Akbar Heydari Leila Ma’mani Seyed Hassan Hosseini 《Comptes Rendus Chimie》2010,13(5):544-547
An efficient and practical protocol for the chemoselective N-Boc protection of various structurally different aryl, aliphatic and heterocyclic amines was carried out with (Boc)2O using protic 1, 1, 3, 3-tetra-methylguanidinium acetate (10 mol%) as recyclable catalyst under solvent free condition at ambient temperature. No competitive side reactions (isocyanate, urea and N, N-di-Boc) were observed. α-Amino alcohols afforded the N-Boc-derivative without oxazolidinone formation. 相似文献
60.
Javad Azizian Ali A. Mohammadi Ilyar Bidar Peiman Mirzaei 《Monatshefte für Chemie / Chemical Monthly》2008,139(7):805-808
A simple, efficient, and practical procedure for the Pechmann condensation using KAl(SO4)2 · 12H2O (alum) as a non-toxic, reusable, inexpensive, and easily available catalyst is described under solvent-free condition at
65°C. These improved reaction conditions allow the preparation of a wide variety of some new substituted coumarins in high
yields (86–96%) and purity under mild reaction conditions. Compared to the classical Pechmann condensation, this new method consistently has the advantage of high yields.
Correspondence: Ali A. Mohammadi, Department of Chemistry, Shahid Beheshti University, P.O. Box 19839-4716, Tehran, Iran. 相似文献