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51.
52.
The supersymmetric solutions of PT -symmetric and Hermitian/non-Hermitian forms of quantum systems are obtained by solving the Schr?dinger equation for the
Exponential-Cosine Screened Coulomb potential. The Hamiltonian hierarchy inspired variational method is used to obtain the
approximate energy eigenvalues and corresponding wave functions.
相似文献
53.
Mehrdad Khatami Rasoul Mehnipor Mohammad Hossein Sobhani Poor Gholamreza Salehi Jouzani 《Journal of Cluster Science》2016,27(5):1601-1612
The objective of the present study was to evaluate efficiency of silver nanoparticles (Ag-NPs) biosynthesis using Descurainia sophia as a novel biological resource. The resulting synthesized Ag-NPs were characterized using UV visible spectroscopy, X-ray diffraction, transmission electron microscopy and dynamic light scattering (DLS). The UV–Vis spectra gave surface plasmon resonance at ~420 nm. TEM images revealed formation spherical shaped Ag-NPs with size ranged from to 1–35 nm. DLS confirmed uniformity of the synthesized Ag-NPs with an average size of ~30 nm. Following, the antibacterial and antifungal activities of the synthesized Ag-NPs were investigated. The concentration 25 µg/ml of the Ag-NPs showed maximum inhibitory effect on mycelium growth of Rhizoctonia solani (More than 86 % inhibition), followed by 15 µg/ml (55 % inhibition) and 10 µg/ml (63 % inhibition). The minimum inhibitory concentration and minimum bactericidal concentration of Ag-NPs against Agrobacterium tumefaciens (strain GV3850) and A, rhizogenes (strain 15843) were 4 and 8 µg/ml, respectively. The Ag-NPs were stable in vitro for 3 months without any precipitation or decrease of antifungal effects. Finally, it could be concluded that D. sophia can be used as an effective method for biosynthesis of nanoparticles, especially Ag-NPs. 相似文献
54.
Optimal economic load dispatch based on wind energy and risk constrains through an intelligent algorithm 下载免费PDF全文
This article focus on optimal economic load dispatch based on an intelligent method of shark smell optimization (SSO). In this problem, the risk constrains has been considered which has root in uncertainity and unpredictable behavior of wind power. Regarding to increasing of this clean energy in power systems and un‐dispatchable behavior of wind power, its conditional value at risk index considered in this article which consists of loss from load and "spilling" wind energy connected with unpredictable imbalances among generation and load. This problem has been considered as an optimization problem based on SSO that evaluate the balance between cost and risk. This algorithm is based on distinct shark smell abilities for localizing the prey. In sharks' movement, the concentration of the odor is an important factor to guide the shark to the prey. In other words, the shark moves in the way with higher odor concentration. This characteristic is used in the proposed SSO algorithm to find the solution of an optimization problem. Effectiveness of the proposed method has been applied over 30‐bus power system in comparison with other techniques. © 2016 Wiley Periodicals, Inc. Complexity 21: 494–506, 2016 相似文献
55.
In this study, manganese porphyrin was grafted on the surface of graphene oxide nanosheets via covalent bonding to produce a heterogeneous catalyst. The prepared nanocomposite was characterized using X-ray diffraction, UV–vis spectroscopy, scanning electron microscopy, Fourier transform infrared, and thermogravimetric analysis. Atomic absorption spectroscopy was also used to determine the amount of the loaded catalyst. The catalytic efficiency of the immobilized Mn-porphyrin was investigated for the aerobic oxidation of alkenes and saturated alkanes in acetone under mild reaction conditions. The prepared heterogenized catalyst displays superior catalytic performance as compared to the homogeneous catalyst. Moreover, the excellent turnover number (more than 31,767) achieved for the oxidation of styrene indicates the high longevity of the supported catalyst. The catalyst structure is preserved well after the oxidation reaction and is simply reused at least five times, without any significant loss of the catalytic efficiency. 相似文献
56.
Gholamreza Khayatian Marzieh Moradi Shahed Hassanpoor 《Journal of Analytical Chemistry》2018,73(5):470-478
The presented study investigates the application of MnO2/3MgO nanocomposite, as a new sorbent for solid phase extraction and determination of trace amounts of Pb2+ and Cu2+ from various samples using flame atomic absorption spectrometry. After extraction, the analytes were desorbed using 0.01 M ethylenediaminetetraacetic acid. The effects of various parameters were studied and optimized. Under optimized experimental conditions the linear dynamic ranges for Cu2+ and Pb2+ were 10?900 and 30?900 μg/L, respectively, with a preconcentration factor of 20. The detection limits of Cu2+ and Pb2+ were 4 and 11 μg/L, respectively, and relative standard deviations for eight determinations of 100 μg/L were 3.6 and 3.8% for Cu2+ and Pb2+, respectively. The method was successfully applied for determination of copper and lead in mushrooms, rice, tap water and refinery wastewater with good spike recoveries ranging between 95?106%. 相似文献
57.
Numerical Algorithms - This paper is devoted to investigate the modified extended second derivative backward differentiation formulae from second derivative general linear methods point of view.... 相似文献
58.
Microchimica Acta - The authors describe a colorimetric method for highly selective determination of cystamine using silver nanoparticles capped with thiomalic acid (TMA-AgNPs). The TMA-AgNPs... 相似文献
59.
There is a mistake in the statement and proof of Theorem 3.8 of the paper ‘Approximation of upper bound for matrix operators on the Fibonacci weighted sequence spaces’ that appeared in this journal (64 (2) (2016) 196–207). In this note, the corrected proof of the revised theorem is presented. 相似文献
60.
Gholamreza Shayeganrad 《Optics & Laser Technology》2012,44(4):987-994
The temperature distribution in the gain medium and key design parameters for an ideal-four level end-pumped solid-state laser have been analyzed depending on the crystal's length, absorption coefficient, and pump beam M2 factor. The optimum key design parameters and thermal focal lens are obtained by minimizing the root mean square of pump beam radius in the laser crystal. It is found that the focal thermal lens and key design parameters are dependent on the gain medium characteristics and pump beam properties as well. By considering the Poisson equation in cylindrical coordinate and Top-Hat pumping profile, an analytical formula has been derived to introduce the thermal focal length in the end-pumped lasers. A formula is also presented to relate the requirements of pump source to the gain medium properties for working laser at the design point. 相似文献