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生物医用Ti6Al4V/xTiN复合材料的腐蚀与腐蚀磨损行为

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Transactions of.Nonf.rrous Metals Society of.China 2022年第2期32卷 540-558页

作者： J.CHÁVEZ O.JIMÉNEZ D.BRAVO-BARCENAS L.OLMOS f.alvarado-hernÁndez M.A.GONZÁLEZ A.BEDOLLA-JACUINDE M.f.ORES Departamento de Ingeniería Mecánica Eléctrica CUCEIUniversidad de GuadalajaraBlvd.Marcelino García Barragán#1421GuadalajaraC.P.44430México Departamento de Ingeniería de Proyectos CUCEIUniversidad de GuadalajaraJoséGuadalupe Zuno#48Los BelenesZapopanC.P.45150México Departamento de Ingeniería de Proyectos CUCEIUniversidad de Guadalajara-CONACyTBlvd.Marcelino García Barragán#1421GuadalajaraC.P.44430México Instituto de Investigaciones en Ciencias de la Tierra INICITUniversidad Michoacana de San Nicolás de HidalgoAv.Francisco J.Mujica S/NCiudad UniversitariaMoreliaMichoacánC.P.58030México Unidad Académica de Ingeniería I Universidad Autónoma de ZacatecasAv.López Valverde 801ZacatecasZacatecasC.P.98060México Instituto de Investigaciones Metalúrgicas IIMMUniversidad Michoacana de San Nicolás de HidalgoEdificio‘‘U-5’’Ciudad UniversitariaMoreliaMichoacánC.P.58030México

用固相烧结法制备Ti6Al4V/xTiN(x=0,5,10,15,体积分数,%)复合材料,研究材料的腐蚀与腐蚀磨损行为及其与显微组织和显微硬度的关系。采用37℃和模拟体液模拟人体环境。结果表明,当TiN含量为15%时,氮(N)固溶到钛(Ti)晶格中使α-Ti稳定化,... 详细信息

用固相烧结法制备Ti6Al4V/xTiN(x=0,5,10,15,体积分数,%)复合材料,研究材料的腐蚀与腐蚀磨损行为及其与显微组织和显微硬度的关系。采用37℃和模拟体液模拟人体环境。结果表明,当TiN含量为15%时,氮(N)固溶到钛(Ti)晶格中使α-Ti稳定化,该显微组织的改变使Ti64基体的硬化效应达到58%。随着TiN颗粒的加入,复合材料的腐蚀电位变得更高,而腐蚀电流密度受残余孔隙率的影响而增大,使材料的耐腐蚀性降低。然而,含15%TiN样品的钝化行为减弱。复合材料的非钝化行为导致其在腐蚀磨损测试过程中电位降低。此外,固溶强化使复合材料的磨损率降低88%。研究结果有利于理解材料的成分和烧结参数与提高腐蚀磨损性能之间的关系。

关键词： Ti64合金复合材料粉末冶金显微组织腐蚀腐蚀磨损

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机械球磨制备Ni_2f.Sb合金的烧结动力学（英文）

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Transactions of.Nonf.rrous Metals Society of.China 2016年第8期26卷 2126-2135页

作者： f.alvarado-hernández O.JIMéNEZ G.GONZALEZ-CASTANEDA V.BALTAZAR-hernández J.CABEZAS-VILLA M.ALBITER H.VERGARA-hernández L.OLMOS Unidad Académica de Ingeniería I Universidad Autónoma de ZacatecasJardín Juárez 147 Centro Histórico Zacatecas Zacatecas C. P. 98000 México Departamento de Ingeniería de Proyectos CUCEI Universidad de GuadalajaraBlvd. Marcelino García Barragán 1421 Olímpica Guadalajara Jalisco C. P. 44430 Mexico INICIT Universidad Michoacana de San Nicolás de HidalgoFco. J. Mujica S/N C.U. Morelia Michoacán C. P. 58060 México División de Estudios de Posgrado e Investigación TecNM/Instituto Tecnológico de MoreliaAv. Tecnológico # 1500 Colonia Lomas de Santiaguito Morelia Michoacán C. P. 58120 México

采用粉末冶金工艺制备Ni2f.Sb三元形状记忆合金。利用膨胀实验研究合金的烧结动力学；采用XRD和SEM分别考察粉末样品和烧结样品的显微组织和形貌；测定烧结样品表面的显微硬度。结果表明：研磨时间对粉末样品的形状、晶粒尺寸和晶体结... 详细信息

采用粉末冶金工艺制备Ni2f.Sb三元形状记忆合金。利用膨胀实验研究合金的烧结动力学；采用XRD和SEM分别考察粉末样品和烧结样品的显微组织和形貌；测定烧结样品表面的显微硬度。结果表明：研磨时间对粉末样品的形状、晶粒尺寸和晶体结构的均匀性具有显著影响。经较长时间研磨的样品具有较高的相对密度和较均匀的元素分布，且为L21和马氏体相，这些性能使合金具有形状记忆功能。在温度为750~1273K条件下，合金的激活能为109~283kJ/mol，这表明烧结过程主要由体积扩散控制。增加研磨时间和加热速率，合金的显微硬度得到提高。

关键词： Ni基形状记忆合金机械球磨固态烧结显微硬度

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The signif.cance of.U-Pb zircon ages in zoned plutons:the case of.the f.amenco pluton, Coastal Range batholith, northern Chile

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Geoscience f.ontiers 2019年第3期10卷 1073-1099页

作者： Natalia Rodríguez Juan Díaz-alvarado Carlos f.rnández Paulina f.entes Christoph Breitkreuz Colombo Celso Gaeta Tassinari Departamento de Geología Universidad de Atacama Departamento de Ciencias de la Tierra Universidad de Huelva Institut f.r Geologie TU Bergakademie Freiberg High Resolution Geochronological Laboratory University of.S?o Paulo

Compositionally zoned plutons, both layered and concentrically arranged, provide granitic exposures where the mechanisms and timing of.the magmatic emplacement processes can be studied. The importance of.in-situ geochemical dif.erentiation and the magma replenishment rates are revealed by geochemistry and f.eld relations, together with the increasingly accurate U-Pb geochronology, which has promoted the knowledge about the pluton incremental assembly *** f.amenco pluton, located in the Coastal Range of.northern Chile, is part of.the Upper Triassic to Early Cretaceous Andean intrusives f.rmed in the western active margin of.South America, and present a normal zoned structure with maf.c magmatic f.cies(mostly gabbros and Qtz-diorites) close to the contacts with the host metasediments, and tonalites, granodiorites and granites in the inner areas. A combined study of.the f.eld relations, geochemistry and zircon geochronology of.the magmatic f.cies was applied to determine the emplacement sequence of.the f.amenco pluton, revealing three distinguishable domains separated by metasedimentary septa. The SW area is constituted by mostly homogeneous leucocratic granodiorites that yielded an age of.213 Ma as the best estimation f.r their emplacement age. Distinctive geochemical characteristics, such as the absence of.an Eu anomaly, the depletion in HREE, or the highest Sr, Sr/Y and Ce/Yb values among the granodioritic f.cies of.the pluton,involve lower T and/or higher P conditions at the magmatic source according to experimental *** conditions were established during an early stage of.the Andean magmatic arc building that is f.rstly def.ned here as Upper Triassic. The NW and E domains of.the pluton were sequentially emplaced between 194 Ma and 186 Ma and both the f.eld relations and the detailed geochronological results suggest that the maf.c f.cies intruded latter in the emplacement sequence. To the NW, Qtz-dioritic and gabbroic externally emplaced pulses ga

关键词： Zircon U-Pb geochronology Zoned plutons Andean magmatic arc Sequential emplacement Individual and statistical zircon ages

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Perf.rmance Comparison among Trained Judges and Panels f.r the Evaluation of.“Cuajada” Type f.esh Cheese in Two Regions f.om Oaxaca in México

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f.od and Nutrition Sciences 2011年第10期2卷 1166-1179页

作者： Lorena Guadalupe Ramón Canul Emmanuel de Jesús Ramírez Rivera Rodrigo Santiago Cabrera f.tima Karina Delgado Vidal José Manuel Juárez Barrientos María hernández Cervantes Juliana López Velázquez Tania Gómez alvarado 不详

f.ur “cuajada” type f.esh cheeses were evaluated by two trained panels in dif.erent regions f.om Oaxaca in Mexico (Instituto Tecnológico de Comitancillo (ITC) and Universidad del Mar (UMAR)). Each panel was integrated by six judges. Analysis of.variance (ANOVA) in conjunction with principal component analysis (PCA) and the Rv coef.icient were used to identif. similarities and consensus among trained judges and panels. The ANOVA results revealed that the judges f.om ITC perf.rmed signif.cantly better (P f.ect in discrimination. The PCA determined some similarities in the position of.cheeses in the sensory space, while Rv revealed that judges and panels were consensual. In conclusion, statistical resources determined that both panels were discriminating and that similarities in the positioning of.cheeses in the sensory space were f.und.

关键词： Af. ANOVA Cuajada Type f.esh Cheese PCA Training Panelists

f.ur New Species and Additional Distributions of.<i>Elaphoglossum</i>Section <i>Elaphoglossum</i>(Dryopteridaceae) f.om the Neotropics

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American Journal of.Plant Sciences 2017年第6期8卷 1234-1247页

作者： Alexander f.ancisco Rojas-alvarado Universidad Nacional de Costa Rica Heredia Costa Rica

f.ur new species of.Elaphoglossum sect. Elaphoglossum are described: E. Amparoanum A. Rojas, E. Chocoense A. Rojas, E. f.yorum A. Rojas and E. Luciae A. Rojas. The f.rst species is related to E. Variolatum Mickel, but dif.ers f.om it by having rhizome scales bicolorous and long ciliate margin. The second species is dif.erent to E. moranii Mickel by having narrower rhizome, shorter stipe, elliptic blade, attenuate blade base, shorter f.rtile f.onds with blackish costa and present at lower altitudinal distribution. Af.er that, the third species dif.ers f.om E. lingua (C. Presl) Brack. by pale rhizome scales with long ciliate margin, shorter f.onds and blade scales denser and lighter. f.nally, the f.urth species is related to E. atrosquamatum Mickel, but with relative longer f.onds and broader blade. The geographical distributions of.E. guatemalense (Klotzsch) T. Moore, E. longicrure Christ, E. minutum (Pohl ex f.e) T. Moore and E. nicaragüense A. Rojas are expanded.

关键词： Dryopteridaceae Elaphoglossum f.rns New Records New Species Section Elaphoglossum Taxonomy

Biomagnetic Validation to Skin Level f.r Blood Pressure Curves and Venous

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Open Journal of.Applied Sciences 2012年第3期2卷 128-134页

作者： T. Cordova-f.aga f.ancisco Gómez-Aguilar T. Bravo-Arellano M. A. hernández-Gonzalez S. Solorio-Meza H. A. Perez-Olivas M. Sosa-Aquino J. J. Bernal-alvarado C. R. Contreras-Gaytan Departamento de Ingeniería f.sica—DCI Universidad de Guanajuato campus León Loma del Bosque León México f.cultad de Ingeniería en Computación y Electrónica Universidad De La Salle Bajío Campus Campestre Lomas del Campestre León México Unidad de Investigaciones Médicas Los Paraísos León México

An analysis of.the reproducibility f.om signal record bioelectric heart activity is presented. The measurements were carried out with a recently patented medical device, which one is able to record the curves of.pressure arterial and venous as those obtained using the gold standard technique in these evaluations, the cardiac catheterization technique. The measurements were carried out 15 health subjects and patients;each one was measured 5 times in order to have auto-correlations and correlations of.these records. Analysis indicates correlations f.om 0.9 to 1 as long as p values were below 0.05. It is indicated an excellent reproducibility of.evaluated patients.

关键词： Bioelectric Heart Activity Curves of Pressure Arterial and Venous Correlation Coef.icient Statistical Analysis

DNA Barcodes in f.g Cultivars (f.cus carica L.) Using ITS Regions of.Ribosomal DNA, the psbA-trnH Spacer and the matK Coding Sequence

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American Journal of.Plant Sciences 2015年第1期6卷 95-102页

作者： Carlos Castro Alejandro hernandez Luis alvarado Dora f.ores Agribiotecnología de Costa Rica S.A. Alajuela Costa Rica Instituto Tecnológico de Costa Rica (ITCR) Cartago Costa Rica

Molecular markers provide a usef.l method f.r genotype characterization and allow a high precision determination of.the genetic relationship between cultivars and varieties. A system based on DNA sequences—which is known as DNA barcoding—will choose one or several standard loci which can be sequenced and compared to dif.erentiate between species. In this research, the ITS, matK, and trnH-psbA sequences were evaluated f.r the molecular identif.cation of.seven f. carica genotypes, generating complete sequences f.r the f.rst two loci, but unable to produce bidirectional sequences by using the trnH-psbA sequence. The ITS sequence presented the highest variation rates, while the phylogeny constructed with the matK sequence obtained the highest percentage of.solved monophyletic groups. Through Pearson’s correlation analysis, it was possible to determine the existence of.a signif.cant correlation between the ITS region and psbA-trnH, and the matK and psbA-trnH sequences, but not between ITS and matK. The phylogenies constructed with the ITS + matK barcodes and ITS + matK + psbA-trnH presented the highest percentage f.r resolution. However, considering the cost ef.iciency and the f.cilitated recovery by using PCR, the matK + ITS combination is recommended.

关键词： f.cus carica DNA Barcodes ITS psbA-trnH matK

高血压患者血管紧张素Ⅱ1型受体自身抗体检出率及其与血压和药物的关系

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中华高血压杂志(中英文) 2021年第8期29卷 798-798页

作者： Philogene MC Han D alvarado f.f.darko NS Zonderman AB Evans MK Crews DC 袁源郑武洪

本研究旨在探究成年高血压患者血管紧张素Ⅱ1型受体自身抗体(antibodies against angiotensinⅡtype 1 receptor,AT1RAb)的检出率,并阐明有AT1RAb个体和无AT1RAb个体中降压药种类与血压的关系。方法:参与者为全生命周期多样化社区健康衰... 详细信息

本研究旨在探究成年高血压患者血管紧张素Ⅱ1型受体自身抗体(antibodies against angiotensinⅡtype 1 receptor,AT1RAb)的检出率,并阐明有AT1RAb个体和无AT1RAb个体中降压药种类与血压的关系。方法:参与者为全生命周期多样化社区健康衰老(healthy aging in neighborhoods of.diversity across the lif. span,HANDLS)研究中的高血压患者,采用酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)法检测血清AT1RAb(阳性定义为≥17U/mL)。测量血压,

关键词：高血压患者检出率

Levels of.TNf.α,IL-1β,TGf.β,and IL-6 in patients with chronic hepatitis C virus inf.ction and hyperinsulinemia

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Open Journal of.Immunology 2013年第1期3卷 17-23页

作者： Luis A.Salazar Xochitl Garcia-Samper Susana Alcazar-Leyva Patricia Gorocica Eduarda Ceron María Cristina Negrete-Garcia Luis f.Montano Noe alvarado-Vásquez Department of.Cell and Tissue Biology Faculty of MedicineNational Autonomous University of MexicoMexico CityMexico Department of.Gastroenterology H.R.“Lic.Adolfo López Mateos”Institute of Security and Social Services for State WorkersMexico CityMexico Institute of.Scientif.c Research“Hans Selye” QueretaroMexico Department of.Biochemistry National Institute of Respiratory Diseases“Ismael Cosio Villegas”Mexico CityMexico

Background: Previous evidences support to inf.ammatory process associated with the IR those important f.ctors in the development of.f.brosis and hepatic damage in patients with HCV inf.ction. Objectives: Determine the presence of.immunological or histological dif.erentces between hyperinsulinemic and non-hyperinsulinemic chronic HCV-inf.cted patients with at least 10 years of.evolution. Material and Methods: The body mass index, Child-Puigh score, liver f.nction tests, and biochemical prof.le were evaluated in 30 control, 40 chronic HCV-inf.cted patients with hyperinsulinemia, and in 40 normoinsulinemic chronic HCV-inf.cted patients with at least 10 years of.evolution. In addition, HCV genotype and viral load were established with the Amplicor System. In addition, nitrites in plasma, and TNf.α, IL-1β, TGf.β, IL-6, and insulin levels were determined. Results: No dif.erences were f.und in BMI, Child-Pugh “A” scores, ALT, viral load, or genotype between the hyperinsulinemic (>25 IU/ml) and normoinsulinemic ( Hyperinsulinemia patients had a higher HOMA- IR value (13.6) than normoinsulinemia patients (3.4), and none had a glycemia > 126 mg/dl. Cy- tokines concentration did not show dif.erences with respect to controls. Nitrites showed a slight increase only in patients with HCV inf.ction. Conclusions: Absence of.changes in the proinf.ammatory cytokines concentration or in some inf.ammation markers in chronic HCV patients with hyperinsulinemia suggests that long-term insulin levels, in presence of.HCV, cannot explain by themselves the hepatic alterations observed in the patient with HCV inf.ction, the presence of.others elements (alcoholism, cirrhosis, etc.) is necessary to onset hepatic damage in these patients.

关键词： Hepatitis C Inf.ammation Hyperinsulinemia Nitric Oxide Type 2 Diabetes Mellitus