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The Interface Stress Field in the Elastic System Consisting of the Hollow Cylinder and Surrounding Elastic Medium Under 3d Non-Axisymmetric Forced Vibration

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Computers, Materials & Continua 2018年第1期54卷 61-81页

作者： Surkay d.Akbarov Mahir A.Mehdiyev Yildiz Technical University Faculty of Mechanical EngineeringDepartment of Mechanical EngineeringYildiz Campus34349 BesiktasIstanbulTurkey Institute of Mathematics and Mechanics of National Academy of Sciences of Azerbaijan 37041 BakuAzerbaijan Azerbaijan State University of Economics(UNEC) Department of Mathematics1001BakuAzerbaijan

The paper develops and employs analytical-numerical solution method for the study of the time-harmonic dynamic stress field in the system consisting of the hollow cylinder and surrounding elastic medium under the non-axisymmetric forced vibration of this *** is assumed that in the interior of the hollow cylinder the point-located with respect to the cylinder axis,non-axisymmetric with respect to the circumferential direction and uniformly distributed time-harmonic forces *** boundary value problem is solved by employing of the exponential Fourier transformation with respect to the axial coordinate and by employing of the Fourier series expansion of these *** results on the frequency response of the interface normal stresses are presented and discussed.

关键词： Interface stress field frequency response hollow cylinder elastic medium forced vibration

Generalized Multiobjective Symmetric duality under Second-Order(F, α, ρ, d)-Convexity

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Acta Mathematicae Applicatae Sinica 2015年第2期31卷 529-542页

作者： S.K.Gupta d.dangar department of Mathematics Indian Institute of Technology Roorkee department of Mathematics and Humanities IT Nirma University

In this paper, we first formulate a second-order multiobjective symmetric primal-dual pair over arbitrary cones by introducing two different functions f ： R^n × R^m → Rk and g ： R^n × R^m → R^l in each k-objectives as well as l-constraints. Further, appropriate duality relations are established under second-order（F, α, ρ, d）-convexity assumptions. A nontrivial example which is second-order（F, α, ρ, d）-convex but not secondorder convex/F-convex is also illustrated. Moreover, a second-order minimax mixed integer dual programs is formulated and a duality theorem is established using second-order（F, α, ρ, d）-convexity assumptions. A self duality theorem is also obtained by assuming the functions involved to be skew-symmetric.

关键词： multiobjective symmetric duality second-order(F α ρ d)-convex duality theorems minimax self duality

Experimental evaluation and simulation of volumetric shrinkage and warpage on polymeric composite reinforced with short natural fibers

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Frontiers of Mechanical Engineering 2015年第3期10卷 287-293页

作者： Jonnathan d. SANTOS Jorge I. FAJARdO Alvaro R. CUJI Jaime A. garcia Luis E. GARZON Luis M. LOPEZ department of Mechanical Engineering Universidad Polit6cnicaSalesiana Elia Liut Ecuador department of Mechanical Engineering Universidad PontificiaBolivariana Medellin Columbia

A polymeric natural fiber-reinforced composite is developed by extrusion and injection molding process. The shrinkage and warpage of high-density polyethylene reinforced with short natural fibers of Guadua angustifolia Kunth are analyzed by experimental measure- ments and computer simulations. Autodesk Moldflow and Solid Works are employed to simulate both volumetric shrinkage and warpage of injected parts at different configurations： 0wt.%, 20wt.%, 30wt.% and 40 wt.% reinforcing on shrinkage and warpage behavior of polymer composite. Become evident the restrictive effect of reinforcing on the volumetric shrinkage and warpage of injected parts. The results indicate that volumetric shrinkage of natural composite is reduced up to 58% with fiber increasing, whereas the warpage shows a reduction form 79% to 86% with major fiber content. These results suggest that it is a highly beneficial use of natural fibers to improve the assembly properties of polymeric natural fiber-reinforced composites.

关键词： biocomposite natural fiber shrinkage,simulation warpage

Modified combustion synthesis of g-LiAlO_2 using metal oxides

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Transactions of Nonferrous Metals Society of China 2018年第9期28卷 1793-1800页

作者： daniel CRUZ H.B.ortiz-OLIVEROS L.M.PéREZ-díAZ R.M.FLORES-ESPINOSA G.ROSANO-ORTEGA Facultad de Ingeniería Química Benemérita Universidad Autónoma de Puebla14 Sur y San ClaudioCiudad UniversitariaC.P.72570Cd.PueblaMéxico Instituto Nacional de Investigaciones Nucleares Dirección de Investigación TecnológicaApartado Postal 18-102711801 MéxicoDFMéxico Universidad Popular Autónoma del Estado de Puebla 21 Sur no.1103Colonia SantiagoC.P.72410PueblaMéxico

An alternative solution for the direct formation of?-LiAlO2 was presented by a modified combustion method,to apply it to rather simple systems,utilizing non-oxidizer compounds such as Al2O3 and LiOH,and urea as ***2 was prepared via non-stoichiometric 1:1,1.5:1 and 2:1 of Li/Al molar ratios at 900 and 1000°C for 5 *** and structural characterization ofγ-LiAlO2 was ***,the effect of different Li/Al molar ratios on material morphology and its stability before high gamma radiation gradients was *** results showed that the crystal structures of the obtained powders wereγ-LiAlO2 and?-LiAlO2,depending on the Li/Al molar *** results obtained demonstrate that?-LiAlO2 microbricks,polyhedral and laminar shapes can be successfully synthesized with the proposed method and without any subsequent ***,gamma irradiation showed that the?-LiAlO2 obtained does not decompose,forming only small amounts of *** can be established that the irradiation produces consolidation,which is not favourable for an efficient extraction of ***,it could be demonstrated that nitrate precursors are not necessary in the combustion method to produceγ-LiAlO2 with high purity.

关键词： urea oxide combustion lithium aluminate ceramic

discoloration on Methylene Blue Solutions by direct and Catalytic Ozonation

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Journal of Materials Science and Chemical Engineering 2013年第5期1卷 33-38页

作者： Antonio d. Rodriguez-Lopez Jose garcia-Garrido Cynthia Perez-Ramiro Esperanza M. garcia-Castello Grupo de Tecnologías de Control de Aguas y Residuos (TECAR) Universitat Politècnica de València Camino de Vera Valencia Spain Grupo de Tecnologías de Control de Aguas y Residuos (TECAR) Universitat Politècnica de ValènciaCamino de Vera Valencia Spain Institute of Food Engineering for development Universitat Politècnica de València Camino de Vera Valencia Spain

during textile manufacturing, huge amounts of wastewaters characterized by removed impurities and high concentrations of dye are produced. These wastewaters cause several problems when they are discharged to the environment. The use of ozone in wastewater treatment results of interest. In this work we propose to assess the discoloration rate of different synthetic wastewaters as a function of pH, dye concentration (methylene blue (MB)) and reaction time. A comparison of discoloration rate between conventional ozonation and catalytic ozonation salts of copper, zinc, silver and nickel was also performed. For the optimization of the ozonation process of colored solutions, it was used a central composite experimental design with five replicates of the center point resulting to evaluate the influence of the independent variables at different ranges of pH, [MB] and time. In the catalyst-assisted ozonation, [MB], pH and the reaction time were fixed to 100 mg/L, 5.5 and 15 min, respectively. The optimized experimental conditions to provide maximum discoloration were pH=3.3;[MB]=8.6 mg/L and time=74.3 min. Regarding the catalyst-assisted ozonation, it was found that CuSO4 catalyst gave better color reduction if compared with other catalysts assayed.

关键词： Textile Wastewater Methylene Blue discoloration Ozonation Catalytic

Fracture energy evaluation on 7075-T651 aluminum alloy welds determined by instrumented impact pendulum

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Transactions of Nonferrous Metals Society of China 2016年第4期26卷 974-983页

作者： R.R.AMBRIZ d.JARAMILLO C.garcia F.F.CURIEL Instituto Politécnico Nacional CIITEC-IPN Cerrada de Cecati S/N Col.Sta.Catarina C.P 02250AzcapotzalcaDFMexico Mechanical and Aerospace Engineering Carleton University1125 Colonel By DriveOttawaONK1S 5B6Canada Universidad Autónoma de Coahuila(UAdeC) Facultad de MetalurgiaCarr 57Km 5MonclovaCoahuilaMexico

By using an instrumented impact pendulum, the force versus time curves of 7075-T651 aluminum welds were obtained from standard Charpy-V samples. Considering the force-time curves and constant impact velocity, the fracture energies for different zones were quantified. A fracture energy improvement for the HAZ(33.6 J) was observed in comparison with the weld metal(7.88 J), and base metal(5.37 J and 7.37 J for longitudinal and transverse directions, respectively). This toughness increment was attributed to the microstructural transformation caused by the thermodynamic instability of η′ precipitates during the welding. Fracture energy for weld metal was higher than that for base metal, probably due to pores created during solidification. Regarding the dynamic yielding force obtained from the force-time curves, an approximation to the dynamic yield strength for weld, HAZ and base metal was determined. Fracture surfaces revealed an intergranular failure for base metal in longitudinal direction, whereas a predominately brittle failure(cleavage) with some insights of ductile characteristics was observed for the transverse direction. In contrast, a ductile failure was observed for weld metal and HAZ.

关键词： 7075-T651 welded joint instrumented Charpy pendulum force-time curve fracture energy dynamic yield strength

Effect of Organic Fertilizer doses on the Plant Growth,Essential Oil Production and Chemical Substances of ＂Carqueja＂ over Two Harvest Moments

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Journal of Agricultural Science and Technology(B) 2017年第2期7卷 114-124页

作者： daniel garcia Paulo Sérgio Siberti da Silva Marcos Roberto Furlan Monica Tiho Chisaki Isobe Marcia ortiz May Marques Lin Chau Ming Horticulture department Faculty of Agronomic Sciences (FCA) Sao Paulo State University "J~lio de Mesquita Filho"18.610-307 Botucatu Sao Paulo Brazil Agronomy department Cantareira Faculty (FIC) 03.020-000 Sao Paulo Brazil Agronomy department University of Mato Grosso State 78.200-000 Caceres Mato Grosso Brazil Natural Products department Agronomic Institute of Campinas (IA C) 13.001-970 Campinas Sao Paulo Brazil

This study aimed to investigate, for the first time, the plant growth, essential oil content and their chemical substances ofBaccharis trimera （Less.） dC., the first Brazilian variety of medicinal plant, in response to five doses of organic fertilizer （0, 10, 20,30, 40 and 50 ton/ha） over two harvest moments-120 d and 242 d after transplanting （dAT）. The work was carried out fromFebruary to October 2011 at the experimental farm of the Sao Paulo State University ＂Julio de Mesquita Filho＂（UNESP）, *** seedlings of B. trimera var. CPQBA-1 were respectively transplanted into experiment plots under six treatments： 0, 10, 20, 30,40 and 50 ton/ha of organic fertilizer. Each treatment had four replications and each plot consisted of 12 plants. Then they wereharvested at 120 dAT and 242 dAT, and the essential oil were extracted by hydrodistillation and analyzed by gas *** results were subjected to analysis of variance and the means were analysed using Tukey＇s test （5%） followed by a regressionanalysis. The fertilizer dose significantly influenced the height of the plants in the second harvest, while the higher dose of organicfertilizer positively impacted the essential oil content in the first harvest. Also, the level of organic fertilizer was directly correlatedwith the production of dry matter during the regrowth. Twenty-seven substances were identified in the essential oil samples, and themajor components were： bicyclogermacrene, trans-caryophyllene, germacrene-d, spathulenol and caryophyllene oxide. Thesefindings suggest that to obtain higher yields of dry matter ofB. trimera, it should be harvested around 242 dAT and organic fertilizershould be applied approximately to 50 ton/ha. Furthermore, higher doses of organic fertilizer and harvest at 120 dAT is able toincrease the essential oil content.

关键词： Baccharis trimera, Brazilian medicinal plant, dry matter, chemical substances, bicyclogermacrene.

Machine learning assisted design of shape-programmable 3d kirigami metamaterials

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npj Computational Materials 2022年第1期8卷 1817-1828页

作者： Nicolas A.Alderete Nibir Pathak Horacio d.Espinosa Theoretical and Applied Mechanics Northwestern UniversityEvanstonIL60208USA department of Mechanical Engineering Northwestern UniversityEvanstonIL60208USA

Kirigami-engineering has become an avenue for realizing multifunctional metamaterials that tap into the instability landscape of planar surfaces embedded with ***,it has been shown that two-dimensional Kirigami motifs can unfurl a rich space of out-of-plane deformations,which are programmable and controllable across spatial *** Kirigami’s versatility,arriving at a cut layout that yields the desired functionality remains a ***,we introduce a comprehensive machine learning framework to shed light on the Kirigami design space and to rationally guide the design and control of Kirigami-based materials from the meta-atom to the metamaterial *** employ a combination of clustering,tandem neural networks,and symbolic regression analyses to obtain Kirigami that fulfills specific design constraints and inform on their control and *** systematic approach is experimentally demonstrated by examining a variety of applications at different hierarchical levels,effectively providing a tool for the discovery of shape-shifting Kirigami metamaterials.

关键词： shape hierarchical shifting

Survivin activity in normal human osteoblasts and osteosarcoma cells

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中国口腔颌面外科杂志 2010年第3期8卷 241-249页

作者： Jan ortiz Maria Gabriela Marquez Henry M. Goldman School of dental Medicine Boston University

PURPOSE: This study was designed to investigate and compare in vitro survivin activity in normal human osteoblast and MG-63 osteosarcoma cell cultures with and without vitamin d3. METHOdS: Normal human alveolar bone explants were recovered from extraction sites of non-carious teeth of 9 healthy donors and cultured to the 2nd passage. MG-63 osteosarcoma cells were obtained from ATCC. To compare the survivin activities in these two types of cells and to determine the effect of vitamin d3 on survivin expression and associated activities of cell proliferation and differentiation, levels of survivin, osteocalcin and alkaline phosphatase were measured at 7-20 day cultures with and without vitamin d3 in both cultures of normal osteoblasts and osteosarcoma cells. Matched pair t-test and two sample independent t-test were applied for statistical analysis of the data. P values of 0.05 or less were considered statistically significant. RESULTS: A significantly higher level of survivin was detected in normal osteoblasts compared to osteosarcoma cells at 7 days without vitamin d3 treatment (Pdecreased after vitamin d3 treatment at 7 days (Pdays of culture (P=NS), compared to that in normal osteoblast culture without vitamin d3 treatment. Vitamin d3 had no effect on survivin expression in osteosarcoma cells at 7 or 20 days (P=NS). CONCLUSIONS: Expression of survivin in cultured normal human osteoblasts and osteosarcoma cells was positively identified. There is a positive correlation between higher expression of survivin and less differentiated osteoblasts that still retain their proliferative ability. Vitamin d3 has significant negative effect on expression of survivin in normal human osteoblasts but not on that in osteosarcoma cells.

关键词： Survivin Osteoblasts Osteosarcoma Apoptosis