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X-ray diffraction analysis by rietveld refinement of FeAl alloys doped with terbium and its correlation with magnetostriction

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journal of rare Earths 2023年第8期41卷 1217-1224,I0004页

作者： j.S.Uribe-chavira G.Herrera-Pérez c.r.Santillán.r.dr.guez r.j.Sáenz-Hernández j.A.Matutes-Aquino M.c.Grijalva-castillo Materials Physics Department Centro de Investigación en Materiales AvanzadosS.C.Miguel de Cervantes 120Chihuahua31136ChihMexico cOnAcYT–centro de Investigación en Materiales Avanzados S.C.Miguel de Cervantes 120Chihuahua31136ChihMexico

Fe_(81)Al_(19) polycrystalline alloys doped with Tb(0-0.25 at%) were obtained by arc *** introduction of Tb favors the formation of columnar grains in the micro structure of the alloys,which develops a texture in the [100]crystal *** examination shows that the alloys are composed in great proportion by the disordered body-centered cubic(bcc),A2 phase and by a small proportion of the ordered bcc,B2 *** a consequence of doping with Tb,the lattice parameter increases,so the calculated apparent crystallite size increases,indicating a decrease in dislocation density and therefore in *** change in the magnetostriction with the magnetic field,dλ_(T)/dH,is directly related to strain anisotropy that can favor the iron easy magnetization axis on the [100] *** increase in total magnetostriction is found in the doped alloys with a maximum of 90 × 10^(-6) at 300 K for the alloy containing 0.027 at% *** enhancement is a threefold value of the undoped alloy,which is attributed to the smaller maximum strain value and the preferential orientation formation by the columnar grains.

关键词： FeAl alloy Magnetostriction rietveld refinement Microstrains Preferred orientation rare earths

Effect of cerium/lanthanum addition on microstructure and mechanical properties of Al7075 alloy via mechanical alloying and sintering

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journal of rare Earths 2016年第4期34卷 420-427页

作者： r.Pérez-Bustamante A.reyna-cruz D.c.Acosta-Pena c.r.Santillán.r.dr.guez j.A.Matutes-Aquino F.Pérez-Bustamante M.c.Maldonado-Orozco j.Aguilar-Santillán r.Martínez-Sánchez research center in Advanced Materials(cIMA V) National Laboratory of NanotechnologyMiguel de Cervantes No.120C.P.31109ChihuahuaChih.Mexico Faculty of Engineering Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31 125ChihuahuaChih.Mexico Faculty of chemical Sciences Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31125ChihuahuaChih.Mexico Materials&Tools LLc 4118 E Washington CtGilbertAZUSA 85234

The effect of the Al-6ce-3La（AcL） on the microstructural behavior of the Al7075 was investigated. Materials were synthesized by mechanical alloying with variation in the AcL content and milling time. Products were characterized and studied in the as-milled condition and mechanically evaluated after sintering. The synergetic effect of milling time and AcL content in the modified materials led to a reduction in the particle size. results from electron microscopy showed a homogeneous dispersion of ce/La phases up to 20 wt.% of AcL content after 10 h of milling. Mechanical evaluation under compressive test showed an improved performance for those alloys reinforced with 0.2 wt.% and 0.5 wt.% of AcL.

关键词： mechanical alloying rare earths aluminum microstructure sintering

Soil conservation Measures in rainfed Olive Orchards in South-Eastern Spain: Impacts of Plant Strips on Soil Water Dynamics

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Pedosphere 2009年第4期19卷 453-464页

作者： V. H. DUrn ZUAZO c. r. rOdríguez PLEguezUELO L. ArrOYO PAnADErO A. MArTínEZ rAYA j. r. FrAncIA MArTínEZ B. crcELES rOdríguez Instituto de Investigación y Formación Agraria y Pesquera IFAPA Centro Camino de Purchil

Sloping and mountainous olive production systems are widespread, occupying large parts of the Mediterranean landscape prone to water erosion. Soil erosion, runoff, and soil water content patterns over a three-year period were monitored in erosion plots on a mountainside with rainfed olive （Olea europaea cv. Picual） trees under： 1） non-tillage with barley strips of 4 m width （BS）; 2） non-tillage with native vegetation strips of 4 m width （nVS）; and 3） non-tillage without plant strips （nT）. The erosion plots, located in Lanjaron （Granada, south-eastern Spain）, on a 30% slope, were 192 m2 in area. For assessing soil water dynamics in real-time and near-continuous soil water content measurements, multisensor capacitance probes were installed in the middle of plant strips and beneath the olive tree at five soil depths （10, 20, 30, 50, and 100 cm）. The highest erosion and runoff rates were measured under nT, with a mean of 17.3 Mg ha-1 year-1 and 140.0 mm year-1, respectively, over the entire study period. The BS and nVS with respect to the nT reduced erosion by 71% and 59% and runoff by 95% and 94%, respectively. In general, greater available soil water content was found under BS than nVS and nT, especially beneath the olive tree canopies. These results supported the recommendation of non-tillage with barley strips in order to reduce erosion and to preserve soil water for trees in traditional mountainous olive-producing areas, where orchards cover vast tracts of land.

关键词： farming systems native plants runoff soil erosion

A Maschke Type Theorem for Weak Hopf Algebras

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Acta Mathematica Sinica,English Series 2008年第12期24卷 2065-2080页

作者： j.n.ALOnSOLVArEZ j.M.FErnnDEZVILABOA r.GOnZLEZrOdríguez A.B.rOdríguezrAPOSO Departamento de Matemáticas Universidad de Vigo. Lagoas-Marcosende Vigo. E-36200 Spain Departamento de lxebra. Universidad de Santiago de compostela Santiago de Compostela. E-15771 Spain Departamento de Matemdtica Aplicada Ⅱ. Universidad de Vigo. Lagoas-Marcosende Vigo. E-36310 Spain Departamento delxebra Universidad de Santiago de CompostelaSantiago de Compostela E-15771 Spain

In this paper, we give a necessary and sufficient condition for a comodule algebra over a weak Hopf algebra to have a total integral, thus extending the classical theory developed by Doi in the Hopf algebra setting. Also, from these results, we deduce a version of Maschke＇s Theorem for （H, B）-Hopf modules associated with a weak Hopf algebra H and a right H-comodule algebra B.

关键词： Monoidal category weak Hopf algebra Hopf modules Maschke Theorem

Influence of ZnO nanoparticles on the microstructure of a cocrFeMoni matrix via powder metallurgy

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International journal of Minerals,Metallurgy and Materials 2019年第11期26卷 1467-1476页

作者： c.D.Gómez-Esparza A.Duarte-Moller c.López-Díaz de León r.Martínez-Sánchez j.F.Hernández-Paz c.A.rodríguez-González centro de investigación en materiales avanzados(cimav) laboratorio nacional de nanotecnologíamiguel de cervantes no.120chihuahua 31136chi8.mexico facultad de ingeniería civil mecánica e industrialuniversidad de la salle bajíoav.universidad 602león 37150gto.mexico instituto de ingeniería y tecnología universidad autónoma de ciudad juárez(uacj)av.del charro 450 nortec4.juárez 32310chi8.mexico

In the last decade,extensive research has been carried out on the microstructural behavior of high-entropy alloys(HEA),for which the in-situ formation of nanoparticles has been ***,studies of the incorporation of nanoparticles in HEA have been rarely *** this work,the addition of zinc oxide nanoparticles(ZnO nP)as reinforcement in a cocrFeMoni high-entropy alloy matrix,as well as the morphological,structural,and microstructural evolution of composites synthesized via powder metallurgy,were *** electron microscopy and X-ray diffraction analysis were performed in order to study the microstructural and phase characterization of the *** sintering,it was found that the ZnO nP addition(0.5 wt%,1 wt%and 2 wt%)had a significant influence on the microstructure and hardness of the cocrFeMoni high-entropy *** bonding among metal particles was promoted with the additions of Zn O nP.A reduction in porosity as a function of ZnO nP content was also *** microhardness results showed that the composite reached its highest reinforcement in bulk samples with 1 wt%ZnO nP(HV 870),which represented a 20%improvement over the unreinforced HEA matrix.

关键词： high-entropy alloy mechanical alloying nanoparticles composites

near shore seismic movements induced by seaquakes using the boundary element method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 571-585页

作者： Alejandro rodríguez-castellanos Manuel carbajal-romero norberto Flores-Guzmán j.Efraín.r.dr.guez-Sánchez Andriy Kryvko instituto mexicano del petróleo eje central lázaro cárdenas 152Gustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalupalmEdif.5Av.Instituto Politécnico Nacional S/NCol.LindavistaGustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalunidad profesional azcapotzalcoDistrito FederalMéxico centro de investigación en matemáticas jalisco s/nmineral de valencianaguanajuatoMéxico

This study quantifies seismic amplifications in near-shore arising from seaquakes. Within the Boundary Element Method, boundary elements are used to irradiate waves and force densities obtained for each element. Huygens′ Principle is implemented since the diffracted waves are constructed at the boundary from which they are radiated, which is equivalent to Somigliana′s theorem. Application of boundary conditions leads to a system of integral equations of the Fredholm type of second kind and zero order. Several numerical configurations are analyzed： The first is used to verify the present formulation with ideal sea floor configurations to estimate seismic amplifications. With the formulation verified, simple slope configurations are studied to estimate spectra of seismic motions. It is found that P-waves can produce seismic amplifications from 1.2 to 3.9 times the amplitude of the incident wave. SV-waves can generate seismic amplifications up to 4.5 times the incident wave. Another relevant finding is that the highest amplifications are at the shore compared to the ones at the sea floor.

关键词： seismic amplifications seaquake earthquake elastic waves boundary element method near shore cities

Long-term follow-up study of gastroduodenal lesions after radioembolization of hepatic tumors

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World journal of Gastroenterology 2013年第19期19卷 2935-2940页

作者： Iago rodríguez-Lago cristina carretero Maite Herráiz josé c Subtil Maite Betés Macarena rodríguez-Fraile jesús j Sola josé I Bilbao Miguel Muoz-navas Bruno Sangro Endoscopy Unit Department of GastroenterologyUniversity of Navarra Clinic31008 PamplonaNavarraSpain Department of nuclear Medicine University of Navarra Clinic31008 PamplonaNavarraSpain Department of Pathology University of Navarra Clinic31008 PamplonaNavarraSpain Department of radiology University of Navarra Clinic31008 PamplonaNavarraSpain Liver Unit University of Navarra Clinic31008 PamplonaNavarraSpain national Biomedical research centre network for Hepatic and Digestive Diseases 08036 BarcelonaCataluaSpain

AIM:To evaluate the long-term natural history of the gastroduodenal lesions secondary to extrahepatic embolization with Ytrium 90(90 Y) ***:From September 2003 to january 2012,379 procedures of liver radioembolization(rE) using resin microspheres loaded with 90 Y were performed in our *** have retrospectively compiled the data from 379 rE procedures performed in our *** report a comprehensive clinical,analytical,endoscopic and histologic long-term follow-up of a series of patients who developed gastroduodenal lesions after the ***:Six patients(1.5%) developed gastrointestinal symptoms and had gastrointestinal lesions as shown by upper endoscopy in the next 12 wk after *** mean time between rE and the appearance of symptoms was 5 *** one patient required endoscopic and surgical *** incidence of gastrointestinal ulcerations was 3.75%(3/80) when only planar images were used for the pre-treatment *** was reduced to 1%(3/299) when singlephoton emission computed tomography(SPEcT) images were also *** symptoms that lasted for a longer time were nausea and vomiting,until 25 mo after the ***:All patients were free from severe symptoms at the end of *** routine use of SPEcT has decreased the incidence of gastrointestinal lesions due to unintended deployment of 90 Y particles.

关键词： radioembolization Liver neoplasms Gastroduodenal ulcer Single-photon emission computed tomography Liver

Prognostic value of ^(13)c-phenylalanine breath test on predicting survival in patients with chronic liver failure

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World journal of Gastroenterology 2007年第34期13卷 4579-4585页

作者： I Gallardo-Wong S Morán G rodríguez-Leal B castaeda-romero r Mera j Poo M Uribe M Dehesa Laboratory of Gastrohepatology research CMN Siglo ⅩⅩI Mexican Institute of Social Security Mexico Gastroenterology Departament CMN Siglo ⅩⅩI Mexican Institute of Social Security Mexico Department of Pathology Louisiana State University Health Sciences Center New Orleans Louisiana United States Hospital Médica Sur Mexico

AIM: To evaluate the prognostic value of percentage of 13c-phenylalanine oxidation (13c-PheOx) obtained by 13c-phenylalanine breath test (13c-PheBT) on the survival of patients with chronic liver failure. METHODS: The hepatic function was determined by standard liver blood tests and the percentage of 13c-PheOx in 118 chronic liver failure patients. The follow-up period was of 64 mo. Survival analysis was performed by the Kaplan-Meier method and variables that were significant (P n univariate analysis and subsequently introduced in a multivariate analysis according to the hazard model proposed by cox. rESULTS: Forty-one patients died due to progressive liver failure during the follow-up period. The probability of survival at 12, 24, 36, 48 and 64 mo was 0.88, 0.78, 0.66, 0.57 and 0.19, respectively. Multivariate analysis demonstrated that child-Pugh classes, age, creatinine and the percentage of 13c-PheOx (Hr 0.338, 95% cI: 0.150-0.762, P = 0.009) were independent predictors of survival. When child-Pugh classes were replaced by all the parameters of the score, only albumin, bilirubin, creatinine, age and the percentage of 13c-PheOx (Hr 0.449, 95% cI: 0.206-0.979, P = 0.034) were found to be independent predictors of ***: Percentage of 13c-PheOx obtained by 13c-PheBT is a strong predictor of survival in patients with chronic liver disease.

关键词： ^13c-phenylalanine breath test Liver cirrhosis chronic liver failure Survival

cytogenetical changes among Polyembryonic(PEm)and non-PEm Maize Plants

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Phyton-International journal of Experimental Botany 2021年第1期90卷 87-97页

作者： A.A.román-calzoncit F.ramírez-Godina j.Sánchez-Laureano A.c.Flores-Gallegos j.Espinoza-Velázquez r.rodríguez-Herrera School of chemistry Universidad Autónoma de Coahuila.Blvd.V.Carranza e Ing.JoséCárdenas V.s/n.Col.República Ote.C.P.25280.SaltilloCoahuilaMéxico Plant Breeding Department Universidad Autónoma Agraria Antonio NarroBlvd.Antonio Narro 1923BuenavistaSaltilloMéxico

Polyembryony in maize(PEm)contributes to improving the nutritional properties of the grain,as well as an increase in yield,since it generates multiple plants per seed,opening the possibility of developing new ***,it is unknown whether polyembryony in maize is the product of chromosomal *** on the above,in this research a cytogenetic study was proposed to verify if chromosomal abnormalities are related to the maize *** a meiotic study,maize genotypes with variable proportions of polyembryony(PEm),from the UA-IMM-BAP population and non-PEm(monoembryonic)maize were used,while for a mitosis analysis,30 families of maternal half-siblings(MHS)from two different populations with high polyembryony,denominated as BHP(brachytic,high polyembryony)and nHP(normal height,high polyembryony)were *** these genotypes were planted in the Buenavista Agricultural Experimental Station-UAAAn at Saltillo,coahuila,*** frequency of PEm was estimated in all *** was found that the polyembryony occurs at frequencies from 34 to 66%in the D-02,BHP group,and from 13 to 21%in the segregating groups of the G3-0202 and *** squash technique was used for both cytogenetic *** meiotic irregularities in maize chromosomes were detected,such as irregular association of 10%of chromosomes in metaphase 1,and agglomeration of chromatin in 100%of the *** addition,pollen viability was estimated by the staining technique with 1%acetocarmine dye,and it was found that the polyembryonic ones have pollen viability of 100%.In meiosis in prophase,I sub-phase diakinesis,ten pairs of bivalents were confirmed,confirming 2n=20,both in non-PEm and PEm maize,corroborating mating,and balanced segregation,without the presence of univalent or *** the chromosomal count carried out in cells in mitosis,only in the BHP-200 polyembryonic family was registered two out of twenty triploid *** condition of ploidy is atypical in

关键词： Zea mays irregular meiosis mitosis chromosomes chromatin polyploidy