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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

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 implem.nting 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

in silico Analysis of osr40c1 Promoter Sequence isolated from indica Variety Pokkali

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Rice science 2017年第4期24卷 228-234页

作者： W.S.i.deSiLVA m.m.n.PERERA K.L.n.S.PERERA A.m.WiCKRamASURiYA G.A.U.JAYASEKERA Department of Plant Sciences Faculty of ScienceUniversity of ColomboColombo 00300Sri Lanka Genetech molecular Diagnostics and School of Gene Technology Colombo 00800Sri Lanka

The promoter region of a drought and abscisic acid （ABA） inducible gene, osr40c1, was isolated from a salt-tolerant indica rice variety Pokkali, which is 670 bp upstream of the putative translation start codon. in silico promoter analysis of resulted sequence showed that at least 15 types of putative motifs were distributed within the sequence, including two types of common promoter elem.nts, TATA and CAAT boxes. additionally, several putative cis-acing regulatory elem.nts which may be involved in regulation of osr40c1 expression under different conditions were found in the 5′-upstream region of osr40c1. These are ABA-responsive elem.nt, light-responsive elem.nts （ATCT-motif, Box i, G-box, GT1-motif, Gap-box and Sp1）, myeloblastosis oncogene response elem.nt （CCAAT-box）, auxin responsive elem.nt （TGA-elem.nt）, gibberellin-responsive elem.nt （GARE-motif） and fungal-elicitor responsive elem.nts （Box E and Box-W1）. A putative regulatory elem.nt, required for endosperm-specific pattern of gene expression designated as Skn-1 motif, was also detected in the Pokkali osr40c1 promoter region. in conclusion, the bioinformatic analysis of osr40c1 promoter region isolated from indica rice variety Pokkali led to the identification of several important stress-responsive cis-acting regulatory elem.nts, and therefore, the isolated promoter sequence could be employed in rice genetic transformation to mediate expression of abiotic stress induced genes.

关键词： osr40c1 promoter cis-acting regulatory elem.nt rice

Effects of confinem.nt on rock mass modulus:A synthetic rock mass modelling(SRm) study

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Journal of Rock mechanics and Geotechnical Engineering 2018年第3期10卷 436-456页

作者： i.Vazaios K.Farahmand n.Vlachopoulos m.S.Diederichs Department of Geological Sciences and Geological Engineering Queen's UniversityKingston Ontario

The main objective of this paper is to examine the influence of the applied confining stress on the rock mass modulus of moderately jointed rocks（well interlocked undisturbed rock mass with blocks formed by three or less intersecting joints）. A synthetic rock mass modelling（SRm） approach is employed to determine the mechanical properties of the rock mass. in this approach, the intact body of rock is represented by the discrete elem.nt method（Dem）-Voronoi grains with the ability of simulating the initiation and propagation of microcracks within the intact part of the model. The geometry of the preexisting joints is generated by employing discrete fracture network（DFn） modelling based on field joint data collected from the Brockville Tunnel using LiDAR scanning. The geometrical characteristics of the simulated joints at a representative sample size are first validated against the field data, and then used to measure the rock quality designation（RQD）, joint spacing, areal fracture intensity（P21）, and block volumes. These geometrical quantities are used to quantitatively determine a representative range of the geological strength index（GSi）. The results show that estimating the GSi using the RQD tends to make a closer estimate of the degree of blockiness that leads to GSi values corresponding to those obtained from direct visual observations of the rock mass conditions in the field. The use of joint spacing and block volume in order to quantify the GSi value range for the studied rock mass suggests a lower range compared to that evaluated in situ. Based on numerical modelling results and laboratory data of rock testing reported in the literature, a semi-empirical equation is proposed that relates the rock mass modulus to confinem.nt as a function of the areal fracture intensity and joint stiffness.

关键词： Synthetic rock mass modelling (SRm) Discrete fracture network (DFn) Rock mass modulus Geological strength index (GSi) Confinem.nt

EPR and magnetic Susceptibility Studies of Cr^(3+) ions in the 70TeO_2·25B_2O_3·5PbO Glass matrix

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Journal of materials Science & Technology 1997年第5期13卷 374-378页

作者： Peteanu, m. Simon, V. muresan, n. Ardelean, i. Faculty of Physics Babes-Bolyai University 3400 Cluj-Napoca Romania Dept. of Physics University of Oradea 3700 Oradea Romania

By using EPR and magnetic susceptibility measurem.nts, the Cr ion distribution in the xCr2O3.(1-x)[70TeO2·25B2O3·5PbO] glasses with 0＜x≤20 mol% was studied. EPR investigation evidencedthe presence of Cr3+ ions in agreem.nt with the experimentally obtained atomic magnetic moment values. For concentrations x≤3 mol%, the isolated Cr3+ ions coexist with those coupledby dipole-dipole interactions. For x＞3 mol%, the Cr3+ ions participate in superexchange interactions and are predominantly antiferromagnetically coupled.

关键词： PbO ions in the 70TeO2 Glass matrix EPR and magnetic Susceptibility Studies of Cr Cr

Vitamin D improves inflammatory bowel disease outcomes:Basic science and clinical review

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World Journal of Gastroenterology 2014年第17期20卷 4934-4947页

作者： Krista m Reich Richard n Fedorak Karen madsen Karen i Kroeker Division of Gastroenterology University of AlbertaEdmontonAlberta T6G 2X8Canada

Vitamin D deficiency is commonly diagnosed among patients with inflammatory bowel disease (iBD). Patients with iBD are at risk of low bone density and increased fractures due to low vitamin D levels, long standing disease, and frequent steroid exposures; as a result, it is well established that vitamin D supplem.ntation in this population is important. There is increasing support for the role of vitamin D in strengthening the innate immune system by acting as an immunomodulator and reducing inflammation in experimental and human iBD. The active form of vitamin D, 1,25(OH)D3, acts on T cells to promote T helper (Th)2/regulatory T responses over Th1/Th17 responses; suppresses dendritic cell inflammatory activity; induces antibacterial activity; and regulates cytokine production in favor of an anti-inflammatory response. murine and human iBD studies support a therapeutic role of vitamin D in iBD. Risk factors for vitamin D deficiency in this population include decreased sunlight exposure, disease duration, smoking, and genetics. Vitamin D normalization is associated with reduced risk of relapse, reduced risk of iBD-related surgeries, and improvem.nt in quality of life. Vitamin D is an inexpensive supplem.nt which has been shown to improve iBD outcomes. However, further research is required to determine optimal serum vitamin D levels which will achieve beneficial immune effects, and stronger evidence is needed to support the role of vitamin D in inducing disease response and remission, as well as maintaining this improvem.nt in patients’ disease states.

关键词： Vitamin D inflammatory bowel disease immune response inflammation Cytokines Supplem.ntation

Divergent molecular and growth responses of young“Cabernet Sauvignon”(Vitis vinifera)plants to simple and mixed infections with Grapevine rupestris stem pitting-associated virus

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Horticulture Research 2020年第1期7卷 2706-2719页

作者： m.Tobar n.Fiore A.G.Pérez-Donoso R.León i.m.Rosales m.Gambardella Pontificia Universidad Católica de Chile Facultad de Agronomía e Ingeniería ForestalVicuña Mackena 4860MaculSantiago 7820436Chile Universidad de Chile Facultad de Ciencias AgronómicasAvenida Santa Rosa 11315La PintanaSantiago 8820808Chile

Grapevine rupestris stem pitting associated virus(GRSPaV)is one of the most widely distributed viruses;even so,little is known about its effect on Vitis *** provide new insights,the effects of single and mixed GRSPaV infections on the *** cultivar“Cabernet Sauvignon”were studied by evaluating growth parameters,such as measurem.nts of the total plant length,the number and distance of internodes and the number of leaves per *** addition,parameters relating to gas exchange,i.e.,the stomatal conductance,net photosynthetic rate,internal CO2 concentration and leaf transpiration,were also *** the measurem.nts were performed in one-and two-yearold plants with a single GRSPaV infection or mixed infections of GRSPaV and Grapevine fanleaf virus(GFLV).The results show that the plant phytosanitary status did not significantly alter the growth and gas exchange parameters in oneyear-old ***,in two-year-old plants,single GRSPaV infections increased shoot elongation,which was accompanied by the overexpression of genes associated with the gibberellic acid response *** gas exchange parameters of these plants were negatively affected,despite exhibiting higher LHCii gene *** with mixed infections did not have modified growth parameters,although they presented a greater reduction in the primary photosynthetic parameters evaluated with no change in LHCii *** results presented here confirm the co-evolution hypothesis for *** and GRSPaV during the early stages of plant development,and they provide new evidence about the effects of GRSPaV and GFLV co-infections on the“Cabernet Sauvignon”cultivar.

关键词： Vitis infections vinifera

Glass and cellulose acetate fibers-supported boehmite nanosheets for bacteria adsorption

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Progress in natural Science:materials international 2017年第2期27卷 268-274页

作者： n.V.Svarovskaya O.V.Bakina E.A.Glazkova A.n.Fomenko m.i.Lerner institute of Strength Physics and materials Sciences of the Siberian Branch of the Russian Academy of Sciences national Research Tomsk Polytechnic University

in this work, in situ method of producing hybrid fibrous adsorbents in which boehmite nanosheets with high sorption properties formed on the surface of hydrophilic microfibres, such as cellulose acetate and glass fibre,was described. The boehmite nanosheets were fabricated by the reaction of composite Al n/Al nanoparticles with water at 60 °C. The synthesized samples were characterized by X-ray diffractometer, scanning, transmission electron microscopy, Fourier transform infrared spectrometer(FT-iR), zeta-potential and specific surface area analyzers. The introduction of microfibres into a diluted aqueous suspension of nanopowders causes heteroadagulation of the nanoparticles and accelerates their further transformation. This effect is most substantial with the glass microfibre, which is thought to have a higher concentration of surface groups capable of generating hydrogen bonds that act as heteroadagulation and nucleation centres. The experimental results showed that the morphology of the resultant hybrid fibrous adsorbents differed accordingly: the nanosheets were attached on-edge to the glass microfibre surface, while on the surface of the cellulose acetate microfibre,they were secured in the form of spherical "nanoflowers" of agglomerated nanosheets. The effect of the morphology of hybrid fibrous adsorbents on adsorption bacteria Escherichia coli was also investigated.

关键词： nanosheets microfibres Hybrid materials Bacterial adsorption

Tb^(3+)substituted strontium hexaferrites:Structural,magnetic and optical investigation and cation distribution

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Journal of Rare Earths 2020年第4期38卷 402-410页

作者： m.A.Almessiere Y.Slimani H.Gungunes m.Sertkol m.nawaz n.A.Algarou A.Baykal i.Ercan Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of Physics Hitit University19030Cevre Yolu Bulvari-CorumTurkey Deanship of Preparatory Year Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia Department of nanomedicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441 DammamSaudi Arabia

in this study,SrFe12-xTbxO19(0.00≤x≤0.1)hexaferrites(HFs)were prepared successfully by citrate solgel approach.X-ray powder diffraction analyses affirm the hexagonal structure of *** phase starts to appear for x≥*** crystallites sizes were estimated to be in the range of 33-46 *** the products exhibit inhomogeneous distribution of grain size detected through *** analyses of magnetization versus applied magnetic field,m(H),were *** measurem.nts were done at room(300 K;RT)and low(10 K)*** different magnetic parameters including saturation magnetization ms,rem.nence mr,squareness ratio(SQR=mr/ms),coercivity Hc,and magnetic moment nB are deduced and discussed in *** both considered temperatures,m(H)results show ferrimagnetic nature for all *** is shown that the Tb substitutions significantly affect m(H)data.A significant increase in the ms,mr,and nB is observed for x=0.02 *** SQR values are around 0.5 indicating the single domain nature with uniaxial *** obtained magnetic results were investigated deeply with relation to structural and microstructural *** spectroscopy results were also *** to mossbauer results,the Tb3+ions preferentially occupy 12 k and 4f2 sites.

关键词： m-type hexaferrites Structure mossbauer spectroscopy Optical properties magnetization Rare earths