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Acta Metallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli M.A. Ghebouli M. Fatmi n. Bouarissa M. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids Materials Department of Physics Faculty of Science University of Setif department of Physics University Center Research Unit on Emerging Materials Ferhat Abbas University of Setif department of Physics Faculty of Sciences King Khalid University Central Metallurgical Research and development Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the M2XC phases depending on the type of M transition metal （M are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are performed using the pseudo-potential plane-wave approach in both the local density and generalized gradient approximations. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic parameters, debye tem- perature, sound velocities and their pressure dependence have been investigated. In agreement with experimental and previous theoretical findings, it is found that the compressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and M elements on the machinability indices of the material have been examined. The electronic properties have been discussed in terms of chemical bonding showing that bonding is due to Md-Cp and Md-Xp hybridizations. M-C bonds are stiffer than M-X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the M-X and M-C bonds increases with increasing the number of VEC.

关键词： M2XC phases ab initio Pressure effect Band structures

Pioglitazone:A review of analytical methods

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Journal of Pharmaceutical Analysis 2014年第5期4卷 295-302页

作者： n.Satheeshkumar S.Shantikumar R.Srinivas department of Pharmaceutical Analysis National Institute of Pharmaceutical Education and ResearchHyderabad (NIPER-H)BalanagarHyderabad 500037India national Center for Mass Spectrometry Indian Institute of Chemical TechnologyTarnakaHyderabad 500607India

Pioglitazone is an oral anti-hyperglycemic agent. It is used for the treatment of diabetes mellitus type 2. It selectively stimulates nuclear receptor peroxisome proliferator-activated receptor gamma （PPAR-gamma）. It was the tenth-best-selling drug in the U.S. in 2008. This article examines published analytical methods reported so far in the literature for the determination of pioglitazone in biological samples and pharmaceutical formulations. They include various techniques like electrochemical methods, spectrophotometry, capillary electrophoresis, high-performance liquid chromatography, liquid chromatography-electrospray ionization-tandem mass spectrometry and high-performance thin layer chromatography.

关键词： Pioglitazone Analytical methods diabetes mellitus type 2

Role of innovative 3d printing models in the management of hepatobiliary malignancies

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World Journal of Hepatology 2019年第7期11卷 574-585页

作者： Peter Bangeas Vassilios Tsioukas Vasileios n Papadopoulos Georgios Tsoulfas department of Surgery Aristotle University of ThessalonikiThessaloniki 54124Greece department of School of Rural and Surveying Engineering Aristotle University of ThessalonikiThessaloniki 54124Greece

Three-dimensional (3d) printing has recently emerged as a new technique in various liver-related surgical fields. There are currently only a few systematic reviews that summarize the evidence of its impact. In order to construct a systematic literature review of the applications and effects of 3d printing in liver surgery, we searched the PubMed, Embase and Sciencedirect databases for relevant titles, according to the PRISMA statement guidelines. We retrieved 162 titles, of which 32 met the inclusion criteria and are reported. The leading application of 3d printing in liver surgery is for preoperative planning. 3d printing techniques seem to be beneficial for preoperative planning and educational tools, despite their cost and time requirements, but this conclusion must be confirmed by additional randomized controlled trials.

关键词： Three-dimensional printing Three-dimensional models Liver Surgery Hepatic phantom models

Analysis of Job Satisfaction of University Professors from nine Chinese Universities

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Frontiers of Education in China 2010年第3期5卷 430-449页

作者： Ping du Manhong Lai Leslie n.K.Lo Faculty of Education Beijing Normal UniversityBeijing 100875China The department of Educational Administration and Policy The Chinese University of Hong KongHong KongChina

Research on work life and job satisfaction of university professors is becoming an important research issue in the field of higher education. This study used questionnaires administered to 1 770 teachers from different levels, types, and academic fields of Chinese universities to investigate job satisfaction among university professors and the relationship between job satisfaction of university professors and the organizational characteristics of the university. The job satisfaction of Chinese university professors includes six dimensions: career development and school management, teaching and research services, salary, benefits and logistical services, professional reputation, teaching and research facilities, and the work itself. The overall job satisfaction levels are close to average, with salary and benefits receiving the lowest level of satisfaction. The organizational characteristics of universities, such as school type, school level, academic field, organizational climate, evaluation orientation, and school management, all have significant effects on the overall job satisfaction of university professors. The organizational climate and school level affect all six dimensions of job satisfaction among university professors.

关键词： job satisfaction university professors organizational characteristics organizational climate

Metabolites and bioactivities of Rhizophoraceae mangroves

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natural Products and Bioprospecting 2013年第5期3卷 207-232页

作者： Murukesh nEBULA H.S.HARISAnKAR n.CHAndRAMOHAnAKUMAR department of Chemical Oceanography School of Marine SciencesCochin University of Science and TechnologyFine Arts AvenueKochi 682016KeralaIndia Inter University Center for development of Marine Biotechnology School of Marine SciencesCochin University of Science and TechnologyFine Arts AvenueKochi 682016KeralaIndia

This review examines the chemical compositions and bioactivities of mangrove plants belonging to the Rhizophoraceae *** Rhizophoraceae family of true mangrove plants is the most common and is also widely distributed *** consists of 24 species across four *** the 24 species,12 species remain unexamined for their phytochemical *** have been 268 metabolites reported from 16 *** key phytochemical constituents identified across the family are the diterpenoids and *** major diterpenoids include pimaranes,beyeranes,kaurenes,dolabranes and labdanes whereas the significant triterpenoids are lupanes,dammaranes and ***,dolabranes and labdanes are considered to be the chemotaxonomic markers of the genera Bruguiera,Ceriops and Rhizophora respectively.

关键词： Rhizophoraceae Bruguiera Rhizophora terpenoids Ceriops

A mathematical analysis of time dependent flow on a rotating cone in a rheological fluid

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Propulsion and Power Research 2017年第3期6卷 233-241页

作者： S.Saleem S.nadeem n.Sandeep department of Sciences and Humanities National University of Computers and Emerging SciencesLahorePakistan department of Mathematics Quaid-I-Azam University45320Islamabad 44000Pakistan Fluid dynamics division VIT UniversityVellore 632014India

In the present study we have explored the time dependent combined convectional flow on a rotating cone in a rotating Jeffrey fluid with the combined effects of heat and mass *** governing equations of motion,energy and mass transfer for unsteady flow are presented and simplified using similar *** reduced coupled nonlinear differential equations are solved analytically with the help of strong analytical technique homotopy analysis *** heat transfer analysis for prescribed wall temperature is *** results for nusselt number and Sherwood number have computed and *** physical features of pertinent parameters are discussed by plotting the graphs of velocity,heat transfer,concentration,skin friction,nusselt number and Sherwood number.

关键词： Combined convection Rotating cone Heat transfer Mass transfer Jeffrey fluid

Optimization of aerodynamic efficiency for twist morphing MAV wing

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Chinese Journal of Aeronautics 2014年第3期27卷 475-487页

作者： n.I.Ismail A.H.Zulkifli M.Z.Abdullah M.Hisyam Basri norazharuddin Shah Abdullah Faculty of Mechanical Engineering Universiti Teknologi MARA Shah Alam 40450 Malaysia School of Mechanical Engineering Universiti Sains Malaysia Engineering Campus Nibong Tebal 14300 Malaysia School of Materials and Mineral Resources Engineering Universiti Sains Malaysia Engineering Campus Nibong Tebal 14300Malaysia

Twist morphing （TM） is a practical control technique in micro air vehicle （MAV） flight. However, TM wing has a lower aerodynamic efficiency （CL/Cd） compared to membrane and rigid wing. This is due to massive drag penalty created on TM wing, which had overwhelmed the succes- sive increase in its lift generation. Therefore, further CL/Cdmax optimization on TM wing is needed to obtain the optimal condition for the morphing wing configuration. In this paper, two-way fluid- structure interaction （FSI） simulation and wind tunnel testing method are used to solve and study the basic wing aerodynamic performance over （non-optimal） TM, membrane and rigid wings. Then, a multifidelity data metamodel based design optimization （MBdO） process is adopted based on the Ansys-designXplorer frameworks. In the adaptive MBdO process, Kriging metamodel is used to construct the final multifidelity CL/Cd responses by utilizing 23 multi-fidelity sample points from the FSI simulation and experimental data. The optimization results show that the optimal TM wing configuration is able to produce better CL/Cdmax magnitude by at least 2% than the non-optimal TM wings. The flow structure formation reveals that low TV strength on the optimal TM wing induces low Cd generation which in turn improves its overall CL/Cdmax performance.

关键词： Aerodynamics Fluid structure interaction Micro air vehicle Optimization Twist morphing

Estimative of real number of infections by COVId-19 in Brazil and possible scenarios

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Infectious disease Modelling 2020年第1期5卷 720-736页

作者： H.P.C.Cintra F.n.Fontinele Physics Institute University of BrasiliaBrasiliaBrazil

This paper attempts to provide methods to estimate the real scenario of the novel coronavirus pandemic in Brazil,specifically in the states of Sao Paulo,Pernambuco,Espirito Santo,Amazonas and the Federal *** the use of a SEIRd mathematical model with age division,we predict the infection and death curves,stating the peak date for Brazil and above *** also carry out a prediction for the ICU demand in these states and for how severe possible collapse in the local health system would ***,we establish some future scenarios including the relaxation on social isolation and the introduction of vaccines and other efficient therapeutic treatments against the virus.

关键词： COVId-19 SEIRd Undernotification Brazil

Observation of dipolar transport in one-dimensional photonic lattices

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Science Bulletin 2017年第5期62卷 339-344页

作者： Camilo Cantillano Luis Morales-Inostroza Bastián Real Santiago Rojas-Rojas Aldo delgado Alexander Szameit Rodrigo A.Vicencio departamento de Física MSI-Nucleus on Advanced Opticsand Center for Optics and Photonics(CEFOP)Facultad de CienciasUniversidad de ChileSantiagoChile Center for Optics and Photonics and MSI-nucleus on Advanced Optics Universidad de ConcepciónCasilla 160-C ConcepcionChile Institute for Physics University of RostockD-18059 RostockGermany

We experimentally study the transport properties of dipolar and fundamental modes on one dimensional(1d) coupled waveguide arrays. By carefully modulating a wide optical beam, we are able to effectively excite dipolar or fundamental modes to study discrete diffraction(single-site excitation) and gaussian beam propagation(multi-site excitation plus a phase gradient). We observe that dipolar modes experience a larger spreading area due to an effective larger coupling constant, which is found to be more than two times larger than the one for fundamental modes. Additionally, we study the effect of non-diagonal disorder and find that while fundamental modes are already trapped on a weakly disorder array, dipoles are still able to propagate across the system.

关键词： Photonic lattices Waveguide arrays Wave propagation Integrated optics

Computational aerodynamic analysis on perimeter reinforced(PR)-compliant wing

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Chinese Journal of Aeronautics 2013年第5期26卷 1093-1105页

作者： n.I.Ismail A.H.Zulkifli M.Z.Abdullah M.Hisyam Basri norazharuddin Shah Abdullah Faculty of Mechanical Engineering Universiti Teknologi MARA40450 Shah AlamSelangorMalaysia School of Mechanical Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia School of Materials and Mineral Resources Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia

Abstract Implementing the morphing technique on a micro air vehicle （MAV） wing is a very chal- lenging task, due to the MAWs wing size limitation and the complex morphing mechanism. As a result, understanding aerodynamic characteristics and flow configurations, subject to wing structure deformation of a morphing wing MAV has remained obstructed. Thus, this paper presents the investigation of structural deformation, aerodynamics performance and flow formation on a pro- posed twist morphing MAV wing design named perimeter reinforced （PR）-compliant wing. The numerical simulation of two-way fluid structure interaction （FSI） investigation consist of a quasi- static aeroelastic structural analysis coupled with 3d incompressible Reynolds-averaged navier- Stokes and shear-stress-transport （RAnS-SST） solver utilized throughout this study. Verification of numerical method on a rigid rectangular wing achieves a good correlation with available exper- imental results. A comparative aeroelastic study between PR-compliant to PR and rigid wing per- formance is organized to elucidate the morphing wing performances. Structural deformation results show that PR-compliant wing is able to alter the wing＇s geometric twist characteristic, which has directly influenced both the overall aerodynamic performance and flow structure behavior. despite the superior lift performance result, PR-compliant wing also suffers from massive drag penalty, which has consequently affected the wing efficiency in general. Based on vortices investigation, the results reveal the connection between these aerodynamic performances with vortices formation on PR-comoliant wing.

关键词： Aerodynamics Aeroelasticity Fluid structure interaction Micro air vehicle (MAV) Morphing wing