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排序方式: 共有138条查询结果,搜索用时 31 毫秒
81.
The Shape invariant method has the algebraic structure and its algebras are infinite-dimensional. These algebras are converted
into finite-dimensional under conditions. Based on the property of this method we obtain the algebraic structure of some physical
potentials in the s-wave Klein-Gordon equation with scalar and vector potential which satisfy the Shape invariant condition. 相似文献
82.
In this paper we study the quantum phase properties of “nonlinear coherent states” and “solvable quantum systems with discrete spectra” using the Pegg-Barnett formalism in a unified approach. The presented procedure will then be applied to few special solvable quantum systems with known discrete spectrum as well as to some new classes of nonlinear oscillators with particular nonlinearity functions. Finally the associated phase distributions and their nonclasscial properties such as the squeezing in number and phase operators have been investigated, numerically. 相似文献
83.
Hatami Mehdi Rahnama Nima Karimi-Maleh Hassan Djafarzadeh Nader Qandalee Mohammad Setva Reza Karimi Fatemeh Durán-Valle Carlos J. López-Coca Ignacio M. Sharifi Alireza 《Cellulose (London, England)》2022,29(12):6677-6696
Cellulose - In this research, a new generation of ternary nanocomposites based on poly(ethylene terephthalate) (PET), phosphorylated chitosan and surface modified alumina nanoparticles were... 相似文献
84.
This paper deals with adaptive estimation of the unknown parameters and states of a pendulum-driven spherical robot (PDSR), which is a nonlinear in parameters (NLP) chaotic system with parametric uncertainties. Firstly, the mathematical model of the robot is deduced by applying the Newton–Euler methodology for a system of rigid bodies. Then, based on the speed gradient (SG) algorithm, the states and unknown parameters of the robot are estimated online for different step length gains and initial conditions. The estimated parameters are updated adaptively according to the error between estimated and true state values. Since the errors of the estimated states and parameters as well as the convergence rates depend significantly on the value of step length gain, this gain should be chosen optimally. Hence, a heuristic fuzzy logic controller is employed to adjust the gain adaptively. Simulation results indicate that the proposed approach is highly encouraging for identification of this NLP chaotic system even if the initial conditions change and the uncertainties increase; therefore, it is reliable to be implemented on a real robot. 相似文献
85.
Microchimica Acta - We have developed a simple and sensitive method for the determination of propranolol in plasma samples. It is based on stir-bar sorptive extraction and HPLC with fluorescence... 相似文献
86.
Electrostatic Assembly/Disassembly of Nanoscaled Colloidosomes for Light‐Triggered Cargo Release
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Song Li Basem A. Moosa Jonas G. Croissant Prof. Niveen M. Khashab 《Angewandte Chemie (International ed. in English)》2015,54(23):6804-6808
Colloidosome capsules possess the potential for the encapsulation and release of molecular and macromolecular cargos. However, the stabilization of the colloidosome shell usually requires an additional covalent crosslinking which irreversibly seals the capsules, and greatly limits their applications in large‐cargos release. Herein we report nanoscaled colloidosomes designed by the electrostatic assembly of organosilica nanoparticles (NPs) with oppositely charged surfaces (rather than covalent bonds), arising from different contents of a bridged nitrophenylene‐alkoxysilane [NB; 3‐nitro‐N‐(3‐(triethoxysilyl)propyl)‐4‐(((3‐(triethoxysilyl)propyl)‐amino)methyl)benzamid] derivative in the silica. The surface charge of the positively charged NPs was reversed by light irradiation because of a photoreaction in the NB moieties, which impacted the electrostatic interactions between NPs and disassembled the colloidosome nanosystems. This design was successfully applied for the encapsulation and light‐triggered release of cargos. 相似文献
87.
Mahmood Tajbakhsh Moosa Ghaemi Siavosh Sarabi Mitra Ghassemzadeh Majid M. Heravi 《Monatshefte für Chemie / Chemical Monthly》2000,131(11):1213-1216
Summary. N-Methyl piperidinium chlorochromate adsorbed on alumina oxidizes a wide variety of benzylic alcohols to the corresponding
carbonyl compounds.
Received May 18, 2000. Accepted (revised) July 4, 2000 相似文献
88.
Fischer-Tropsch synthesis over ruthenium-promoted Co/Al2O3 catalyst with different reduction procedures
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Ali Karimi Ali Nakhaei Pour Farshad Torabi Behnam Hatami Ahmad Tavasoli Mohammad Reza Alaei Mohammad Irani 《天然气化学杂志》2010,19(5):503-508
The effect of reduction procedure on catalyst properties, activity and products selectivity of ruthenium-promoted Co/γ-Al2O3 catalyst in Fischer-Tropsch synthesis (FTS) was investigated. Catalyst samples were reduced with different reduction gas compositions and passivated before being characterized by TPR and XRD techniques. Different activity and product selectivity analyses were also performed. These results showed that the catalyst dispersion, particle size, and the degree of reduction changed with different reduction gas compositions, which were resulted from the water partial pressures in reduction process that give varying degrees of interaction with the support. It has been suggested that the FTS activity of cobalt catalyst was directly dependent on the catalyst reducibility. A reduction gas with a molar ratio of H2/He = 1 was used to prevent the formation of Co-support compound during catalyst reduction. 相似文献
89.
M.R. Setare O. Hatami 《理论物理通讯》2009,51(6):1000-1002
Based on the shape invariance property we obtain exact solutions of the three-dimensional relativistic Klein Gordon equation for a charged particle moving in the presence of a certain varying magnetic field, and we also show its non-relativistic limit. 相似文献
90.
The correspondence between definable connected groupoids in a theory T and internal generalised imaginary sorts of T, established by Hrushovski in [“Groupoids, imaginaries and internal covers,” Turkish Journal of Mathematics, 2012], is here extended in two ways: First, it is shown that the correspondence is in fact an equivalence of categories, with respect to appropriate notions of morphism. Secondly, the equivalence of categories is shown to vary uniformly in definable families, with respect to an appropriate relativisation of these categories. Some elaborations on Hrushovki's original constructions are also included. 相似文献