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NLO response of derivatives of benzene, stilbene and diphenylacetylene：mP2 and DFT calculations

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Chinese Journal of Chemical Engineering 2017年第6期25卷 800-808页

作者： a.m. Elhorri m. Zouaoui-Rabah Laboratoire de microscopie Microanalyse et Spectroscopie Mol&ulaire Faculty of Sciences Djillali Liabes University of Sidi-Bel-Abbes 22000 Sidi-BeI-Abbes Algeria

mP2 method and different functionals such as m06-HF, m06-2X, CAm-B3 LYP, PBE0, B3 LYP and m06 L incorporating different XC amounts were used to calculate the static first hyperpolarizabilies β(0) of eight molecules which are derivatives of benzene, stilbene and diphenylacetylene. The values were then compared to the experimental ones. The m06-2X functional was then selected for further calculations. NBO calculations were also performed to define the intramolecular charge transfer in each molecule. TD-DFT calculations were performed taking into account the solvent effect using the IEF-PCm formalism. Some parameters characterizing the vertical transitions such as the wavelength of the maximum absorption λ_(max) were compared to the experimental ones. Finally,solvation Gibbs free enthalpy ΔG_(solv) values have also been examined in order to determine which the specific solvent for a given molecule is.

关键词： First hyperpolarizability DFT TD-DFT Push-pull molecules NBOCharge transfer

Effect of Electroplating Parameters on microstructure of Nanocrystalline Nickel Coatings

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Journal of materials Science & Technology 2010年第1期26卷 82-86页

作者： a.m. Rashidi A. Amadeh Faculty of Engineering Razi University School of metallurgy & materials Engineering University College of Engineering University of Tehran

In order to achieve the optimum conditions for electroplating nanocrystalline nickel coating from Watts-type bath, the effect of some process parameters namely, bath temperature, current density, and saccharin addition on grain size and texture coefficient （TC= I（200）/I（111）） of the deposits were investigated by X-ray diffraction （XRD）. The results showed that in a bath containing 5 g/L saccharin, by increasing the bath temperature from 45℃ to 55℃, the grain size decreased, whereas further increase of bath temperature resulted in a contrary effect. By increasing the current density from 10 to 75 mA/cm^2, both the grain size and TC decreased, while further increase in current density had no significant effect on the grain size. At a given current density, the grain size and TC decreased rapidly by increasing the saccharin content before leveling off at 3 g/L of saccharin. Finally, based on the grain refining the optimum conditions for producing nanocrystalline nickel coating from Watts-type bath have been proposed.

关键词： Electroplating Grain size Nanocrystalline Coating

Characterization and separation of pyrite from Abu Tartur black shale

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International Journal of mining Science and Technology 2015年第4期25卷 565-571页

作者： Ibrahim S.S. El Ka.m.r a.m. Guda a.m. Central metallurgical R&D Institute CMRDI Geology Dept. Faculty of Science National Research Astronomical & Geophysical Institute NRIAG

This work a.m.d for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled in Abu Tartur plateau representing the pyrite-rich black shale of the U. Cretaceous age, Sample characterization was carried out using petrographic microscope, XRD, DTA/DTG, C/S and XRF techniques. Clay minerals, silt-sized quartz, calcite, and hematite were the main minerals associating pyr- ite （5.34g）. Liberation behavior of the sample was about 80% below 5 μm. Sample processing was achieved through one-day soaking followed by classification using I inch mozley hydro-cyclone where about 35.5% by weight went to underflow and 64.5% went to overflow. The underflow product was subjected to an advanced gravity separation process using SB-40 Falcon Concentrator through a CCD statistical design prepared by Design-Expert 6.0 software proposed to opti- mize the separation process through a study for the effects of frequency （Hz） and water pressure （Psi） on both assay and recovery of the sulfur-rich heavy fraction. A heavy concentrate weighed 10.90% with inorganic sulfur content reached 11.37% （21.24% pyrite） with overall recovery （50.01%） was obtained after two cleaning at the optimum conditions.

关键词： Abu Tartur plateau Black shale Pyrite Falcon Concentrator

Effective Lower Bounds of Wrap-Around L_2-Discrepancy on Three-Level Combined Designs

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Journal of Systems Science & Complexity 2017年第6期30卷 1459-1469页

作者： ELSAWAH a.m. HU Jianwei QIN Hong Faculty of mathematics and Statistics Central China Normal University Division of Science and Technology BNU-HKBU United International College Department ofmathematics Faculty of Science Zagazig University

How to obtain an effective design is a.m.jor concern of scientific research. This topic always involves high-dimensional inputs with limited resources. The foldover is a quick and useful technique in construction of fractional designs, which typically releases aliased factors or *** paper takes the wrap-around L_2-discrepancy as the optimality measure to assess the optimal three-level combined designs. New and efficient analytical expressions and lower bounds of the wraparound L_2-discrepancy for three-level combined designs are obtained. The new lower bound is useful and sharper than the existing lower bound. Using the new analytical expression and lower bound as the benchmarks, the authors may implement an effective algorithm for constructing optimal three-level combined designs.

关键词： Combined design Foldover plan L2-discrepancy lower bound optimal combined design wrap-around

Timoshenko inclusions in elastic bodies crossing an external boundary at zero angle

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Acta.m.chanica Solida Sinica 2017年第3期30卷 327-333页

作者： a.m. Khludnev T.S. Popova Lavrentyev Institute of Hydrodynamics of R_AS Novosibirsk State University Novosibirsk 630090 Russia North-Eastern Federal University Yakutsk 677000 Russia

The paper concerns an analysis of equilibrium problems for 2D elastic bodies with a thin Timoshenko inclusion crossing an external boundary at zero angle. The inclusion is assumed to be delaminated, thus forming a crack between the inclusion and the body. We consider elastic inclusions as well as rigid inclusions. To prevent a.m.tual penetration between the crack faces, inequality type boundary conditions are imposed at the crack faces. Theorems of existence and uniqueness are established. Passages to limits are investigated as a rigidity parameter of the elastic inclusion going to infinity.

关键词： Thin Timoshenko inclusion Crack Delamination Fictitious domain method Non-penetration

Orderly decorated nanostructural photoelectrodes with uniform spherical TiO2 particles for dye-sensitized solar cells

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Frontiers of Chemical Science and Engineering 2015年第4期9卷 532-540页

作者： a.m. Bakhshayesh S.S. Azadfar Department of Research and Development SUN Nanotechnologists Company Tehran 13488-96394 Iran

This study presents a novel nanostructural electrode made of 20-nm-diameter nanoparticles, which orderly decorated with 2-μm TiO2 particles, deposited by a new gel process. The decorated electrode （DE） is better than the non-decorated electrode （NE） in both light scattering and light harvesting, as confirmed by diffuse reflectance spectroscopy. X-ray diffraction reveals that both electrodes have a.m.xture of anatase and rutile phases. The dye-sensitized solar cell based on the decorated electrode shows the highest power conversion efficiency of 7.80% as a result of less recombination demonstrated by electrochemical impedance spectroscopy. From internal power conversion efficiency measurement, the external quantum efficiency of DE cell at 530 nm is 89%, which is higher than that of NE cell （77%）.

关键词： dye-sensitized solar cell uniform particles,TiO2 gel process light harvesting

Electron Acceleration by microwave Radiation Inside a Rectangular Waveguide

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Pla.m. Science and Technology 2011年第3期13卷 357-361页

作者： B. F. mOHAmED a.m. GOUDA Pla.m. Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the fields associated with a transverse magnetic （Tm） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations for an electron are solved, which was injected initially along the propagation direction of the microwave. Expressions of the acceleration gradient and deflection angle are obtained. In principle, it is shown that the electron can be accelerated in this condition and there is no deflection when the electron is injected from the centre of the waveguide front. However, it is found that the acceleration gradient and deflection angle depend strongly on the parameters of the microwave （intensity, frequency, etc.） and the dimensions of the waveguide.

关键词： waveguide electron acceleration polarized microwave

Implementation Study of Dynamic Load Balancing Algorithm of Parallel Tree Computation on Clusters of Heterogeneous Workstation

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Journal of Donghua University(English Edition) 2005年第2期22卷 81-86页

作者： moha.m.d a.m. Ibrahim m.Saifmokbel Faculty of Engineering Department of Software Engineering Taiz University Republic of Yemen Taiz city P. O.Box:6038

The rapid growth of interconnected high performance workstations has produced a new computing paradigm called clustered of workstations computing. In these systems load balance problem is a serious impediment to achieve good performance. The main concern of this paper is the implementation of dynamic load balancing algorithm, asynchronous Round Robin (ARR), for balancing workload of parallel tree computation depth-first-search algorithm on Cluster of Heterogeneous Workstations (COW) many algorithms in artificial intelligence and other areas of computer science are based on depth first search in implicitty defined trees. For these algorithms a load-balancing scheme is required, which is able to evenly distribute parts of an irregularly shaped tree over the workstations with minimal interprocessor communication and without prior knowledge of the tree’s shape. For the (ARR) algorithm only minimal interprocessor communication is needed when necessary and it runs under the mPI (message passing interface) that allows parallel execution on heterogeneous SUN cluster of workstation platform. The program code is written in C language and executed under UNIX operating system (Solaris version).

关键词： cluster of workstations parallel tree computation dynamic load balancing performance metrics

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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