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金属间化合物和低孔隙率TiC烧结体在热压下界面的扩散、挤压和反应行为(英文)

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稀有金属材料与工程 2012年第2期41卷 203-207页

作者：巫红燕高明霞 oliveira filipe J 朱丹潘颐 Vieira Joaquim M 浙江大学硅材料国家重点实验室 University of Aveiro Aveiro3810-193Portugal

分别以Fe40Al、Ni3Al和TiAl(NbCr)金属间化合物为基体,在一定的压力和温度下,使其和低孔隙率TiC粉体烧结体有效结合。采用扫描电镜及能谱仪等对其界面的组织结构进行分析。结果表明,所有金属间化合物均与TiC烧结体形成了冶金结合的界面... 详细信息

分别以Fe40Al、Ni3Al和TiAl(NbCr)金属间化合物为基体,在一定的压力和温度下,使其和低孔隙率TiC粉体烧结体有效结合。采用扫描电镜及能谱仪等对其界面的组织结构进行分析。结果表明,所有金属间化合物均与TiC烧结体形成了冶金结合的界面。TiC烧结体在高温保压过程中有微量分解,扩散进入了Fe40Al和Ni3Al基体表层,降低了其熔点,从而使其成为可流动状态,被挤压进入TiC烧结体的孔隙。但TiAl(NbCr)合金未能进入TiC烧结体孔隙,而是在与TiC的界面处形成了一层Ti含量高于基体约10at%的反应层。

关键词：双结构材料连接微观结构金属间化合物 TiC

Antiglycation and antioxidant activities of the crude extract and saponin fraction of Tribulus terrestris before and after microcapsule release

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Journal of Integrative Medicine 2022年第2期20卷 153-162页

作者： Célia Cristina Malaguti Figueiredo Amanda da Costa Gomes filipe oliveira Granero Joao Luiz Bronzel Junior Luciana Pereira Silva Valdecir Farias Ximenes Regildo Márcio Goncalves da Silva Institute of Chemistry São Paulo State UniversityAraraquaraSão Paulo 14800-060Brazil Educational Foundation of the City of Assis AssisSão Paulo 19807-130Brazil Department of Chemistry School of SciencesSão Paulo State UniversityBauruSão Paulo 17033-360Brazil Department of Biotechnology School of SciencesHumanities and LanguagesSão Paulo State UniversityAssisSão Paulo 19806-900Brazil

Objective:The present study investigated antiglycation and antioxidant activities of crude dry extract and saponin fraction of Tribulus *** also developed a method of microencapsulation and evaluated antiglycation and antioxidant activities of crude dry extract and saponin fraction before and after microcapsule ***:Antiglycation activity was determined by relative electrophoretic mobility(REM),free amino groups and inhibition of advanced glycation end-product(AGE)*** activity was determined by 2,2-diphenyl-1-picrylhydrazyl(DPPH),ferric ion-reducing antioxidant power(FRAP),nitric oxide(NO)and thiobarbituric acid reactive species(TBARS)*** were prepared using maltodextrin as wall material and freeze-drying as encapsulation *** characterization of microcapsules was evaluated by scanning electron microscopy,and encapsulation efficiency and microcapsule release were determined by total saponins *** and antioxidant assays were performed using crude dry extract and saponin fraction of *** before and after ***:Saponin fraction showed an increase of 32.8%total ***-performance liquid chromatography-mass spectrometry analysis showed the presence of saponins in the obtained *** evaluation by REM demonstrated that samples before and after release presented antiglycation activity similar to bovine serum albumin treated with ***,samples inhibited AGE formation,highlighting treatment with saponin fraction after release(89.89%).Antioxidant tests demonstrated antioxidant activity of the *** dry extract before encapsulation presented the highest activities in DPPH(92.00%)and TBARS(32.49%)*** fraction before encapsulation in FRAP test(499μmol Trolox equivalent per gram of dry sample)and NO test(15.13μmol nitrite formed per gram of extract)presented the highest ***:This study presen

关键词： Glycation Microencapsulation Oxidative stress Saponins Tribulus terrestris

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Pathogenesis and clinical management of arboviral diseases

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World Journal of Virology 2025年第1期14卷 9-50页

作者： Victoria Cenci Dietrich Juan Marcos Caram Costa Marina Maria Gomes Leite oliveira Carlos Eduardo oliveira Aguiar Luis Guilherme de oliveira Silva Marcel Silva Luz Fabian Fellipe Bueno Lemos Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

Arboviral diseases are viral infections transmitted to humans through the bites of arthropods,such as mosquitoes,often causing a variety of pathologies associated with high levels of morbidity and *** the past decades,these infections have proven to be a significant challenge to health systems worldwide,particularly following the considerable geographic expansion of the dengue virus(DENV)and its most recent outbreak in Latin America as well as the difficult-tocontrol outbreaks of yellow fever virus(YFV),chikungunya virus(CHIKV),and Zika virus(ZIKV),leaving behind a substantial portion of the population with complications related to these ***,the world is experiencing a period of intense globalization,which,combined with global warming,directly contributes to wider dissemination of arbovirus vectors across the ***,all continents remain on high alert for potential new ***,this review aims to provide a comprehensive understanding of the pathogenesis of the four main arboviruses today(DENV,ZIKV,YFV,and CHIKV)discussing their viral characteristics,immune responses,and mechanisms of viral evasion,as well as important clinical aspects for patient *** includes associated symptoms,laboratory tests,treatments,existing or developing vaccines and the main associated complications,thus integrating a broad historical,scientific and clinical approach.

关键词： Arboviruses Arbovirus infections Dengue Zika virus Yellow fever Chikungunya virus Clinical diagnosis Pathogenesis Flavivirus Togaviridae infections

Creeping fat and gut microbiota in Crohn’s disease

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World Journal of Gastroenterology 2025年第1期31卷 16-23页

作者： Ana EV Quaglio Daniéla O Magro Marcello Imbrizi Ellen CS De oliveira Luiz C Di Stasi Ligia Y Sassaki Verum Ingredients Botucatu Technology ParkBotucatu 18605-525São PauloBrazil Department of Surgery Faculty of Medical SciencesState University of CampinasCampinas 13083-970São PauloBrazil Department of Gastroenterology Faculty of Medical SciencesUniversity of CampinasCampinas 13083-970São PauloBrazil Department of Internal Medicine Medical SchoolSão Paulo State UniversityBotucatu 18618-686São PauloBrazil Department of Biophysics and Pharmacology Institute of BiosciencesSão Paulo State UniversityBotucatu 18618-689São PauloBrazil

In this article,we explored the role of adipose tissue,especially mesenteric adipose tissue and creeping fat,and its association with the gut microbiota in the pathophysiology and progression of Crohn’s disease(CD).CD is a form of inflammatory bowel disease characterized by chronic inflammation of the gastrointestinal tract,influenced by genetic predisposition,gut microbiota dysbiosis,and environmental *** microbiota plays a crucial role in modulating immune response and intestinal inflammation and is associated with the onset and progression of ***,visceral adipose tissue,particularly creeping fat,a mesenteric adipose tissue characterized by hypertrophy and fibrosis,has been implicated in CD pathogenesis,inflammation,and *** bacteria from the gut microbiota may translocate into mesenteric adipose tissue,contributing to the formation of creeping fat and influencing CD *** creeping fat may be a protective barrier against bacterial invasion,its expansion can damage adjacent tissues,leading to *** gut microbiota through interventions such as fecal microbiota transplantation,probiotics,and prebiotics has shown potential in managing ***,more research is needed to clarify the mechanisms linking gut dysbiosis,creeping fat,and CD progression and develop targeted therapies for microbiota modulation and fat-related complications in patients with CD.

关键词： Creeping fat Mesenteric adipose tissue Gut microbiota Crohn’s disease Inflammatory bowel disease

The Recompositions of Buus＇（1547）RicercariFrom His Libro primo.., in Manuscript P-Cug MM 242 and the Didactic Processes of the Friars of the Santa Cruz Monastery in Coimbra.

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History Research 2013年第6期3卷 423-440页

作者： filipe Mesquita de oliveira Universidade de l~vora l~vora Portugal

The purpose of this articleis to address the presence of seven recomposed ricercari by Jacques Buus in the Music Manuscript 242 from the Library of the University of Coimbra in Portugal （P-Cug MM 242）. These recompositions, probably copied in the third quarter of the 16th century, were made after the previously copied Buus＇s ricercari in Music Manuscript 48 （P-Cug MM 48） of the same library, which were based on the Libro primo de ricercari a quattrovoci, published in Venice in 1547 by Antonio Gardane. In this paper, the author intend to focus in two main aspects of the research done on this subject. The first topic concerns the score-format of both manuscripts 48 ＆ 242, which testify the instrumental activity in mid-sixteenth century Portugal. The author will demonstrate that this format served once, in the Santa Cruz Monastery in Coimbra, as a didactic tool in the teaching of counterpoint through the music of a northern European master such as Jacques Buus. The copies in the manuscripts were never intended to be used as a performing support--they contain many errors of vertical coordination between the voices that make the performance impossible. The second topic focuses on Buus＇ recomposed ricercari, which were the object of many cuts, brief recomposed bridges, newly inserted sections, and written glosa figurations. Through these recompositions, the author will describe the theoretic assimilation of formal processes, of style, mode, counterpoint and performing practice. The achievement of this paper is to offer historic musicology researchers a new perspective about the enormous influence that Buus＇ ricercari from his Libro primo.., had in the learning processes of music composition and in the development of didactic and performing practices in the Santa Cruz Monastery in Coimbra, during the mid-sixteenth century.

关键词： Jacques Buus P-Cug MM 242 Ricercare Portuguese instrumental music from the 16h century Scoreformat manuscripts

Influence of PVD-duplex-treated, Bionic Surface Structures on the Wetting Behavior for Sheet-Bulk Metal Forming Tools

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Journal of Bionic Engineering 2017年第3期14卷 520-531页

作者： Wolfgang Tiilmann Dominic Stangier Nelson filipe Lopes Dias Institute of Materials Engineering TU Dortmund 44227 Dortmund Germany Leonhard-Euler-Strafle 2

Bionic surface structures, inspired by the flora, were developed for Sheet-Bulk Metal Forming （SBMF） in order to locally control the friction condition by adjusting the wetting behavior. Five bionic structures were micromilled on ASP 2023 in annealed as well as hardened and tempered conditions. Subsequently, the structured surfaces were plasma-nitrided and coated with a CrA1N thin film. The influence of the treatment method on the structural geometry was investigated with the aid of a scanning electron microscope and 3D-profilometer. The wetting behaviors of water and deep drawing oil （Berufluid ST6007） on bionic surfaces were evaluated using contact angle measurements. The resulting micro-milled structures exhibit an almost identical shape as their bionic models. However, the roughness of the structured surfaces is influenced by the microstructure. The combination of plasma-nitriding and Physical Vapor Deposition （PVD） leads to an increase in roughness. All bionic struc- tures possess higher contact angles than that of the unstructured surfaces when wetted by water. This can be explained by the fact that the structural elevations block the spreading. When the bionic surfaces are wetted by deep drawing oil, the lubricant spreads in the structural cavities, leading to smaller contact angles. Furthermore, the anisotropy of the structure has an influence on the wetting behavior.

关键词： bionic structures sheet-bulk metal forming CrA1N PVD-duplex treatment wetting behavior

Analysis of alternative parameters of dynamic resistance measurement in high voltage circuit breakers

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High Voltage 2019年第3期4卷 197-202页

作者： Herbet filipe dos Santos Sousa Adriano Costa de oliveira George Victor Rocha Xavier Henrique Nunes de Santana Edson Guedes da Costa Tarso Vilela Ferreira Federal University of Campina Grande Campina GrandeBrazil Federal University of Sergipe AracajuBrazil

Throughout its lifetime,high-voltage circuit breaker(HVCB)contacts suffer from inevitable degradation processes,especially during the formation of electric *** degraded contacts can reduce the current interruption capacity and increase the chances of operational faults,which might lead to considerable financial ***,the use of efficient evaluating techniques is a key factor to achieve systems *** dynamic resistance measurement(DRM)is a technique that can be used to evaluate the degradation level of HVCB'*** stands out from the usual technique,static resistance measurement,by allowing the assessment of both the main contacts and the arcing contacts(ACs).Usually,the mean resistance or the area under the DRM curve is used to estimate the AC ***,DRM is a non-standardised technique and there are no specified parameters to evaluate the real wear ***,an analysis of alternative parameters extractible from the DRM technique is presented in this study,such as amplitude and variance of the DRM *** results attest the possible use of more than one parameter for the continuous evaluation of HVCB ACs,characterising the DRM as a more complete and precise diagnosis tool.

关键词： resistance parameters dynamic

Fragility Assessment of Pre-Northridge Steel Moment Frames Using Finite-Length Plastic Hinge Elements and Concentrated Plasticity Fracture Elements

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Computer Modeling in Engineering & Sciences 2019年第9期120卷 657-676页

作者： filipe L.A.Ribeiro Andre RBarbosa Luis CNeves National Laboratory of Civil Engineering(LNEC)&CERIS-Civil Engineering Research and Innovation for Sustainability DECivilUniversity of LisbonLisbonPortugal School of Civil and Construction Engineering Oregon State UniversityOregonUSA and University of BristolBristolUK Resilience Engineering Research Group University of NottinghamNottinghamUK.

Although pre-Northridge earthquake steel moment resisting frame buildings have been shown to be susceptible to brittle connection failures,they still represent a large fraction of the existing steel buildings in the United States of *** this study,the performance of the 3-and 9-story Los Angeles pre-Northridge SAC buildings are analyzed considering ductile and brittle beam-column connection failures,and their *** paper contributes to understanding the influence of uncertainty associated with connections brittle fracture on building interstory deformation capacity and its impact on bias and variability of fragility functions and loss *** results show that considering brittle connections leads to significantly l arger d rift demands a nd t o h igher r epair costs,particularly under intense ground *** fragility curve parameters are derived that account for the effect of the uncertainty of the strength and deformation capacity of brittle connections.

关键词： Brittle fracture finite-length p lastic h inge f ragility c urves r epair c ost ratio welded-flange connections

Evolution of the ring-like vortices and spike structure in transitional boundary layers

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 514-520页

作者： oliveira Maria Department of Mathematics University of Texas at Arlington Arlington Texas 76010 USA

At the late stage of transitional boundary layers, the nonlinear evolution of the ring-like vortices and spike structures and their effects on the surrounding flow were studied by means of direct numerical simulation with high order accuracy. A spatial transition of the flat-plate boundary layers in the compressible flow was conducted. Detailed numerical results with high resolution clearly represented the typical vortex structures, such as ring-like vortices and so on, and induced ejection and sweep events. It was verified that the formation of spike structures in transitional boundary layers had close relationship with ring-like vortices. Especially, compared to the newly observed positive spike structure in the experiments, the same structure was found in the present numerical simulations, and the mechanism was also studied and analyzed.

关键词： boundary layer transition ring-like vortices spike structure direct numerical simulation

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