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Conformable and Caputo’s Derivatives in Generalized Viscoelastic Models

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Applied Mathematics 2023年第9期14卷 580-601页

作者： jorge Fujioka Rosalío Fernando rodrígue. Áurea Espinosa-Cerón Instituto de Física Dpto. de Sistemas Complejos Universidad Nacional Autónoma de México Ciudad de México México Facultad de Ciencias Universidad Nacional Autónoma de México Ciudad de México México

We study two generalized versions of a system of equations which describe the time evolution of the hydrodynamic fluctuations of density and velocity in a linear viscoelastic fluid. In the first of these versions, the time derivatives are replaced by conformable derivatives, and in the second version left-handed Caputo’s derivatives are used. We show that the solutions obtained with these two types of derivatives exhibit significant similarities, which is an interesting (and somewhat surprising) result, taking into account that the conformable derivatives are local operators, while Caputo’s derivatives are nonlocal operators. We also show that the solutions of the generalized systems are similar to the solutions of the original system, if the order α of the new derivatives (conformable or Caputo) is less than one. On the other hand, when α is greater than one, the solutions of the generalized systems are qualitatively different from the solutions of the original system.

关键词： Conformable Derivatives Caputo’s Derivatives Fractional Derivatives Viscoelastic Fluids Hydrodynamic Fluctuations

Effects of a poly(hydroxyalkanoate)elastomer and kraft pulp fibres on biocomposite properties and three-dimensional(3D)printability of filaments for fused deposition modelling

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Journal of Bioresources and Bioproducts 2022年第3期7卷 161-172页

作者： Sandra rodrígue.-Fabià Gary Chinga-Carrasco RISE PFI Høgskoleringen 6bTrondheim 7491Norway

Three-dimensional(3D)printing is a useful technique that allows the creation of objects with complex structures by deposition of successive layers of *** materials are often from fossil ***,efforts are being made to produce environmentally friendly materials for 3D *** addition of lignocellulosic fibres to a polymer matrix is one of the alternatives to replace,for instance,glass fibres in composites as reinforcing *** fields of biocom-posites and 3D printing open innovative application areas for pulp fibres from the pulp and paper *** this work,biocomposites of poly(lactic acid)(PLA),poly(hydroxyalkanoate)(PHA)and kraft pulp fibres were prepared in order to find a suitable formulation for filaments for 3D *** effect of two different types of kraft fibres(bleached(B)and unbleached(U))and of PHA on the mechanical and thermal properties of the biocomposites was *** addition of 30%kraft fibres to PLA resulted in an increase of the tensile modulus from 3074 to∼4800 *** the case of biocomposites containing PHA(50%PLA/20%PHA/30%kraft)the increase in modulus was more moderate(PLA+PHA+U:3838 MPa,and PLA+PHA+B:3312 MPa).The tensile strength of PLA(66 MPa)increased to 77 MPa in PLA+kraft biocomposites,while a reduc-tion in strength was observed for PLA+PHA+U(43 MPa)and PLA+PHA+B(32 MPa).Filaments prepared with PLA,PHA and bleached and unbleached pulp fibres showed similar printability of complex geometries,demonstrating that unbleached pulp fibres could also be utilized in the preparation of biocomposites with good mechanical performance and 3D printing properties.

关键词： biocomposites 3D printing Poly(lactic acid) Kraft pulp

Effect of an electron gas on a neutron-rich nuclear pasta

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Nuclear Science and Techniques 2015年第2期26卷 75-82页

作者： jorge Alberto Lopez Enrique Ramirez-Homs Department of Physics University of Texas at El Paso

We studied the role that electron gas has on the formation of nuclear structures at subsaturation densities and low temperatures(T<1 Me V).Using a classical molecular dynamics model we studied isospin symmetric and asymmetric matter at subsaturation densities and low temperatures varying the Coulomb interaction *** effect of such variation was quantified on the fragment size multiplicity,the inter-particle distance,the isospin content of the clusters,the nucleon mobility and cluster persistence,and on the nuclear structure *** found that the presence of an electron gas distributes matter more evenly,disrupts the formation of larger objects,reduces the isospin content,and modifies the nucleon average displacement,but does not affect the inter-nucleon distance in *** nuclear structures are also found to change shapes by different degrees depending on their isospin content,temperature and density.

关键词：电子气体分子动力学模型面食中子相互作用强度核结构同位旋平均位移

Calculations of Optical Rotation from Density Functional Theory

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Chinese Physics Letters 2007年第5期24卷 1207-1209页

作者： Antǒnio Canal Neto Francisco Elias jorge Departamento de Fisica Universidade Federal do Espírito Santo 29060-900 Vitória ES Brazil

Density function theory calculations of frequency-dependent optical rotations [α]ω for three rigid chiral molecules are reported. Calculations have been carried out at the sodium D line frequency, using the ADZP basis set and a wide variety of functionals. Gauge-invariant atomic orbitals are used to guarantee origin-independent values of [ω]D. In addition, study of geometry dependence of [ω]D is reported. Using the geometries optimized at the B3LYP/ADZP level, the mean absolute deviation of B3LYP/ADZP and experimental laiD values yields 60.1°/（dm g/cm^3）. According to our knowledge, this value has not been achieved until now with any other model.

关键词： MOLECULAR WAVE-FUNCTIONS BASIS-SETS MP2 HF

Marriage Market with Indifferences: A Linear Programming Approach

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Journal of the Operations Research Society of China 2023年第1期11卷 219-242页

作者： Noelia Juarez Pablo A.Neme jorge Oviedo Instituto de Matemática Aplicada San Luis IMASLRedNIEUniversidad Nacional de San Luis and CONICETD5700HHWSan LuisRepublica Argentina

We study stable and strongly stable matchings in the marriage market with indifference in their *** characterize the stable matchings as integer extreme points of a convex *** give an alternative proof for the integrity of the strongly stable matching ***,we compute men-optimal(women-optimal)stable and strongly stable matchings using linear *** preferences are strict,we find the men-optimal(women-optimal)stable matching.

关键词： Matching markets The marriage market with indifferences Optimal stable matchings Linear programming

Liquid-liquid interfacial tension of equilibrated mixtures of ionic liquids and hydrocarbons

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Science China Chemistry 2012年第8期55卷 1519-1524页

作者： rodrígue. Héctor ARCE Alberto SOTO Ana Department of Chemical Engineering University of Santiago de Compostela E-15782 Santiago de Compostela Spain

Ionic liquids are possible alternative solvents for the separation of aromatic and aliphatic hydrocarbons by liquid-liquid extrac- tion. Interfacial tension is an important property to consider in the design of liquid-liquid extraction processes. In this work, the liquid-liquid interfacial tension and the mutual solubility at 25 ℃ have been measured for a series of biphasic, equilibrated mixtures of an ionic liquid and a hydrocarbon. In particular, the ionic liquids 1-alkyl-3-methylimidazolium bis（trifluorome- thanesulfonyl）imide （with the alkyl substituent being ethyl, hexyl or decyl）, 1-ethyl-3-methylimidazolium ethylsulfate, and 1-ethyl-3-methylimidazolium methanesulfonate have been selected, as well as the hydrocarbons benzene, hexane, ethylben- zene, and octane. The selected sets of ionic liquids and hydrocarbons allow the analysis of the influence of a series of effects on the interfacial tension. For example, the interfacial tension decreases with an increase in the length of the alkyl substituent chain of the cation or with an increase of the degree of charge delocalisation in the anion of the ionic liquid. Also, the interfa- cial tension with the aromatic hydrocarbons is markedly lower than that with the aliphatic hydrocarbons. A smaller effect is caused by variation of the size of the hydrocarbon. Some of the observed trends can be explained from the mutual solubility of the hydrocarbon and the ionic liquid.

关键词： ionic liquid aromatic hydrocarbon aliphatic hydrocarbon interfacial tension liquid-liquid equilibrium

Fatigue.severity of patients with idiopathic chronic fatigue.compared to healthy subjects

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Journal of Traditional Chinese Medicine 2012年第3期32卷 355-357页

作者： Nam Hun Lee Chang gue.Son Liver and Immunology Research Center Daejeon Oriental Hospital of Daejeon University

OBJECTIVE:To analyze the fatigue.severity of patients with idiopathic chronic fatigue.ICF) and to compare the severity of this group with that of healthy ***:one hundred and nine ICF patients and 98 healthy subjects were enrolled in this *** severity was measured using the Korean-translated Chalder fatigue.severity *** subjects scored each item on a 10-point scale as a self-rating numeric scale(NRS),and additionally rated their feeling of general fatigue.by visual analogue.scale(VAS).RESULTS:The total NRS scores of patients with ICF was 53 ± 15 compared with 25 ± 14 of healthy subjects(2.4 folds for physical symptoms vs.1.7 folds for mental symptoms respectively).The VAS scores of patients with ICF were 2.7 times as high as those of healthy ***:This report is the first to compare the severity of fatigue.between ICF patients and healthy *** study contains reference data applicable for the management of this disorder in field of complementary and alternative medicine.

关键词： Fatigue.syndrome,chronic Pain measurement Quality of life

Positive interactions by cushion plants in high mountains:fact or artifact?

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Journal of Plant Ecology 2016年第2期9卷 117-123页

作者： Marco A.Molina-Montenegro Rómulo Oses Ian S.Acuña-rodrígue. Cristian Fardella Ernesto I.Badano Patricio Torres-Morales jorge Gallardo-Cerda Cristian Torres-Díaz Instituto de Ciencias Biológicas Universidad de TalcaAvda.Lircay s/nTalcaChile Centro de Estudios Avanzados en ZonasÁridas(CEAZA) Facultad de Ciencias del MarUniversidad Católica del NorteCoquimboChile División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaCamino a la Presa San José2055Colonia Lomas ta Sección CP 78216San Luis PotosíSLPMéxico 4 Instituto de Ciencias Ambientales y EvolutivasUniversidad Austral de ChileValdiviaChile Departamento Científico Instituto Antártico Chileno(INACH)Punta ArenasChile Laboratorio de Genómica y Biodiversidad(LGB) Departamento de Ciencias NaturalesUniversidad del Bío-BíoChillánChile

Positive interactions are defined as non-trophic interactions where at least one of the interacting species is benefited in terms of fitness and the other remains ***,the bidirectional feedbacks between species may be positive,neutral or ***,if facilitated species induce negative effects on their‘nurses’,the assumed definition of positive interactions could be *** We assessed if ecological interactions between cushions of Azorella madreporica and their facilitated species are ***,we tested if cover of facilitated species has any costs for cushion plants from an ecophysiological perspective,and if these costs increase with the amount of cover of facilitated *** addition,through pathway analysis and correlations,we assessed if cover and richness of facilitated species have a direct and/or indirect effect on the fitness of cushion *** Findings We found that facilitated plant species induced a significant cost for their nurses(cushion plants),and this cost increases with cover of the facilitated ***,the facilitated species exert a strong direct negative effect on the cushion’s fitness and a moderate indirect negative cost evident through the nutrient status and physiological performance of cushion *** thus contribute evidence that positive interactions between high mountain cushion plants of central Chile and their‘facilitated’species may be an artifact more than a fact,especially when bidirectional effects are considered;contrasting with the majority of studies that document only one side of the interaction.

关键词： cushion plants facilitation nurse effect positive interactions stress gradient hypothesis

Weak crossed biproducts and weak projections

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Science China Mathematics 2012年第7期55卷 1321-1352页

作者： FERNNDEZ VILABOA Jose Manuel GONZLEZ rodrígue. Ramon rodrígue. RAPOSO Ana Belen Departamento de lxebra Universidad de Santiago de Compostela Departamento de Matemtica Aplicada II Universidade de Vigo Departamento de Matemticas Universidade da Coruna

In this paper, we present the general theory and universal properties of weak crossed biproducts. We prove that every weak projection of weak bialgebras induces one of these weak crossed structures. Finally, we comput... 详细信息

关键词： braided monoidal category preunit crossed product weak Hopf algebra weak projection weakcrossed biproduct