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Journal of Materials Science & Technology 2018年第1期34卷 119-127页

作者： Alessandro Barbini Jan Carstensen jorge f.dos santos Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics Solid-State Joining Processes (WMP)

friction stir welding （fSW） and stationary shoulder friction stir welding （SSfSW） were carried out for the butt joining of dissimilar AA2024-T3 and AA7050-T7651 aluminium alloys with thicknesses of 2 mm. A comparison between the two processes was performed by varying the welding speed while keeping the rotational speed constant, Through the analysis of the force and torque produced during welding and a simple analytical model, it was possible to show that in SSfSW there is more effective coupling with the tool and the heat produced is more efficiently distributed. This process decreases both the welding area and the diffusion at the interface of the two alloys compared with fSW. The minimum microhardness occurred at the advancing side （AS） at the interface between the thermo-mechanically affected zone （TMAZ） and the stir zone （SZ） in both processes, although the decrease was more gradual in SSfSW. This interface is also where all specimens failed for both welding technologies. An increase in tensile strength was measured in SSfSW compared with standard fSW. furthermore, it was possible to establish the mechanical performance of the material in the fracture zone using digital image correlation.

关键词： Stationary shoulder friction stir welding friction stir welding Dissimilar welded joints Process analysis Microstructure analysis Mechanical behaviour

Assessing the Bonding Interface Characteristics and Mechanical Properties of Bobbin Tool friction Stir Welded Dissimilar Aluminum Alloy Joints

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Acta Metallurgica Sinica(English Letters) 2021年第1期34卷 125-134页

作者： Quan Wen Wenya Li Vivek Patel Luciano Bergmann Benjamin Klusemann jorge f.dos santos State Key Laboratory of Solidifi cation Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China Institute of Materials Research Materials MechanicsSolid-State Joining ProcessesHelmholtz-Zentrum GeesthachtMax-Planck-Straße 121502 GeesthachtGermany Institute of Product and Process Innovation Leuphana University of LüneburgUniversitätsallee 121335 LüneburgGermany

This study focuses on the bonding interface characteristics and mechanical properties of the bobbin tool friction stir welded dissimilar AA6056 and AA2219 aluminum alloy joints using diff erent welding *** arise solely in the stir zone at the AA2219 side.A distinct boundary with limited material mixing develops at the middle section of the bonding interface,while excellent material mixing with an irregularly jagged pattern forms at the top and bottom sections of the bonding *** the welding speed,the material mixing is rarely changed at the middle section in comparison with the bottom ***,a small diff erence between Guinier–Preston dissolution and Q phase precipitation leads to rare change of hardness in the heat aff ected zone(HAZ)at the AA6056 *** increased hardness of the HAZ at the AA2219 side is attributed to avoidance of the dissolution ofθ’’phase precipitates.A maximum tensile strength of 181 MPa is obtained at 300 mm *** occur at the AA6056 side near the top and bottom surfaces and at the bonding interface in the middle section of the *** regions close to the top and bottom surfaces of the joints show a better ductility.

关键词： Bobbin tool friction stir welding Dissimilar aluminum alloy Bonding interface Precipitation Mechanical property

Application of novel constrained friction processing method to produce fine grained biomedical Mg-Zn-Ca alloy

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Journal of Magnesium and Alloys 2024年第2期12卷 516-529页

作者： Ting Chen Banglong fu Junjun Shen Uceu f.H.R.Suhuddin Björn Wiese Yuanding Huang Min Wang jorge f.dos santos Jean Pierre Bergmann Benjamin Klusemann Solid State Materials Processing Institute of Material MechanicsHelmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany functional Magnesium Materials Institute of Metallic BiomaterialsHelmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiao Tong UniversityDongchuan Road 800Shanghai 200240China Applied Materials and Manufacturing Energy and Environment DivisionPacific Northwest National LaboratoryPO Box 999RichlandWA 99352USA Production Technology Group Technisiche Universität IlmenauGustav-Kirchhoff-Platz 2Ilmenau 98693Germany Institute for Production Technology and Systems Leuphana University of LüneburgUniversitätsallee 1Lüneburg 21335Germany

In order to obtain Mg alloys with fine microstructures and high mechanical performances,a novel friction-based processing method,name as“constrained friction processing(CfP)”,was *** CfP,defect-free Mg-Zn-Ca rods with greatly refined grains and high mechanical properties were *** to the previous as-cast microstructure,the grain size was reduced from more than 1 mm to around 4μm within 3 s by a single process *** compressive yield strength was increased by 350%while the ultimate compressive strength by 53%.According to the established material flow behaviors by“tracer material”,the plastic material was transported by shear *** the base material to the rod,the material experienced three stages,*** by the tool,upward flow with additional tilt,followed by upward *** microstructural evolution was revealed by“stop-action”*** microstructural development at regions adjacent to the rod is mainly controlled by twinning,dynamic recrystallization(DRX)as well as particle stimulated nucleation,while that within the rod is related to DRX combined with grain growth.

关键词： Constrained friction processing Magnesium alloys Microstructure Mechanical properties Grain refinement Plastic deformation

Integrating Project Management, Software Development, and Knowledge Management Models: A Case Study in a Public ICT Services Organization

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Social Networking 2023年第1期12卷 1-27页

作者： jorge Luiz dos santos Renelson Ribeiro Sampaio SERPRO Servi&#231 o federal de Processamento de Dados Salvador Brazil SENAI CIMATEC University Center Salvador Brazil

In project-based organizations knowledge is a critical resource used to develop and deliver products and services with a high level of quality. Therefore, a systematic and sustainable process is necessary to coordinate knowledge management, project management and product lifecycle. This scenario predominates in companies focused on the creation and maintenance of information systems. This article presents an exploratory study based on a framework that integrates cognitive, managerial, and operational processes in a public Brazilian organization that provides services in the area of information and communications technology, focusing on the construction and maintenance of information systems. Those processes are operationalized by three management models considering knowledge, project, and software development processes. Our proposal aims to understand the relationships between those three management models and their influence on the software development process in the organization under study. Our premise is based on the principle that cognitive management, project management, and software development management must be integrated to fulfill the demands of product development and service provision. The research data was composed of registers of working hours spent on software development and maintenance projects involving 244 people allocated to 5064 projects in the period from 2007 to 2013. The study resulted in the identification of the relationships among the three management models adopted by the organization, with emphasis on knowledge management activities, which were not directly identified, making it difficult to account for and measure them. We established a set of activities connected to each one of the knowledge management model phases. Since those activities were not visible before, our approach contributed to build a systematic process to register and relate activities linked to the dimensions of cognitive processes, project management, and software con

关键词： Knowledge Management Knowledge Sharing Integrated Management Project Teams Software Development

Interpreting Nestedness and Modularity Structures in Affiliation Networks: An Application in Knowledge Networks formed by Software Project Teams

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Social Networking 2021年第1期10卷 1-18页

作者： jorge Luiz dos santos Renelson Ribeiro Sampaio federal Data Processing Service-Serpro Salvador Brazil University Center Senai Cimatec Salvador Brazil

An understanding of the knowledge creation and diffusion process in the organizational context is extremely relevant. Because from this understanding, organizations can restructure processes, reorient teams and implement methodologies to assist in the construction of an evolutionary process of knowledge creation and diffusion aimed at sustainable growth and innovation. The theory of complex social networks has been applied in several fields to help understand organizational cognitive processes. However, these approaches still insipiently consider the analysis of the nestedness and modularity of the studied networks. In this article, we presented an approach that sought to identify patterns of nestedness and modularity in networks of affiliation of people in projects in the organizational context. The study sought to identify these patterns in affiliation networks in a public organization providing information technology services in the period from 2006 to 2013. The detection of these patterns was performed using the NODf (Nestedness metric based on Overlap and Decreasing fill) algorithm described by f="#ref1">[1]. The nestedness and modularity metrics can influence patterns of knowledge creation and diffusion in formal and informal networks constituted for the execution of projects in organizations. This study showed that the network structures of the organization during the study period presented a high degree of nestedness, and it was possible to identify combined structures of nestedness and modularity.

关键词： Social Network Analysis Affiliation Networks Modularity Nestedness

Temporal Analysis of the Diffusion of Knowledge in Networks of Software Maintenance and Development Project Team

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Social Networking 2019年第3期8卷 122-146页

作者： jorge Luiz dos santos Renelson Ribeiro Sampaio Computational Modelling and Industrial Technology SENAI CIMATEC University Campus Salvador Brazil

Different approaches have been established for applications of social and complex networks involving biological systems, passing through collaborative systems in knowledge networks and organizational systems. In this latter application, we highlight the studies focused on the diffusion of information and knowledge in networks. However, most of the time, the propagation of information in these networks and the resulting process of creation and diffusion of knowledge, have been studied from static perspectives. Additionally, the very concept of diffusion inevitably implies the inclusion of the temporal dimension, due to that it is an essentially dynamic process. Although static analysis provides an important perspective in structural terms, the behavioral view that reflects the evolution of the relationships of the members of these networks over time is best described by temporal networks. Thus, it is possible to analyze both the information flow and the structural changes that occur over time, which influences the dynamics of the creation and diffusion of knowledge. This article describes the computational modeling used to elucidate the creation and diffusion of knowledge in temporal networks formed to execute software maintenance and construction projects, for the period between 2007 and 2013, in the SERVIÇO fEDERAL DE PROCESSAMENTO DE DAdos (fEDERAL DATA PROCESSING SERVICE-SERPRO)—a public organization that provides information and communication technology services. The methodological approach adopted for the study was based on techniques for analyzing social and complex networks and on the complementary extensions that address temporal modeling of these networks. We present an exploratory longitudinal study that enabled a dynamic and structural analysis of the knowledge networks formed by members of software maintenance and development project teams between 2007 and 2013. The study enabled identification of knowledge categories throughout this period, in addi

关键词： Knowledge Diffusion Complex Networks Social Networks Temporal Networks

Harmonia axyridis Pallas(Coleoptera:Coccinellidae):Biological aspects and thermal requirements

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Advances in Entomology 2014年第1期2卷 42-46页

作者： Tatiana de Oliveira Ramos Terezinha Monteiro dos santos-Cividanes francisco jorge Cividanes Lais da Conceicao dos santos Department of Plant Health Faculdade de Ciencias Agrarias e VeterinariasUniversidade Estadual PaulistaJaboticabalBrazil Agencia Paulista de Tecnologia dos Agronegocios(APTA) Regional Centro LesteRibeirao PretoBrazil

The aim of this study was to determine the biological aspects and thermal requirements of Harmonia axyridis Pallas (Coleoptera: Coccinellidae) fed daily with Anagasta kuehniella (Zeller) (Lep-idoptera: Pyralidae) eggs. Under laboratory conditions, the experiment was carried out in acclimatized chambers set to 18°C, 21°C, 24°C, 27°C, and 30°C. Larvae of H. axyridis were separated, kept in a glass tube, and fed with A. kuehniella eggs. The Asiatic lady beetle adults were separated into 20 couples and kept in plastic cups receiving the same food as the larvae. The length of the larval, pupal, and total biological cycle (from egg to adult) stages declined significantly from 18°C to 27°C, but was stable between 27°C and 30°C. Survival was similar for larvae from the first to the fourth stadium when kept at 18°C, 21°C, and 24°C with a higher total biological cycle survival at 27°C. H. axyridis males presented higher longevity at 18°C and 21°C in comparison to females that had a longer life and a higher fecundity at 24°C and 27°C, respectively. The lower thermal limit for biological cycle development was 12.4°C, and the thermal constant was 243.9 degree-days.

关键词： Anagasta kuehniella Biological Control Degree-Days

Three-Dimensional Shear Wave Velocity Structure of the Northeastern Brazilian Lithosphere

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International Journal of Geosciences 2016年第6期7卷 849-872页

作者： jorge Luis de Souza Newton Pereira dos santos Carlos da Silva Vilar Coordena?ao de Geofísica MCTI/Observatório Nacional Rio de Janeiro Brazil Departamento de física da Terra e do Meio Ambiente Universidade Federal da Bahia (UFBA) Brazil

A large number of Rayleigh wave dispersion curves recorded at twenty three seismic stations was used to investigate the 3-D shear wave velocity structure of the northeastern Brazilian lithosphere. A simple procedure to generate a three-dimensional image of Mohorovicic;discontinuity was applied in northeastern Brazil and the Moho 3-D image was in agreement with several isolated crustal thicknesses obtained with different geophysical methods. A detailed 3-D S wave velocity model is proposed for the region. In the crust, our model is more realist than CRUST2.0 global model, because it shows more details either laterally or in depth than global model, i.e., clear lateral variation and gradual increase of S wave velocity in depth. Down to 100 km depth, the 3-D S wave velocity model in northeastern Brazil is dominated by low velocities and this is consistent either with heat flow measurements or with measurements of the flexural strength of the lithosphere developed in the South American continent. Our 3-D S wave velocity model was also used to obtain the lithosphere thickness in each cell of the northeastern Brazil and the results were consistent with global studies about the Lithosphere-Asthenosphere Boundary worldwide.

关键词： Rayleigh Waves Group-Velocity Tomography Three-Dimensional Shear Wave Velocity Lithosphere Spatial Resolution Northeastern Brazil

All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.S.Gomes f.E.jorge A.Canal Neto Departamento de fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties

New Insights into Aluminum Tolerance in Rice： The ASR5 Protein Binds the STAR1 Promoter and Other Aluminum-Responsive Genes

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Molecular Plant 2014年第4期7卷 709-721页

作者： Rafael Augusto Arenhart Yang Bai Luiz felipe Valter de Oliveira Lauro Bucker Neto Mariana Schunemann felipe dos santos Maraschin jorge Mariath Adriano Silverio Gilberto Sachetto-Martins Rogerio Margis Zhi-Yong Wang Marcia Margis-Pinheiro Programa de Pos-Graduacao em Genetica e Biologia Molecular Avenida Bento Goncalves 9500 Departamento de Genetica sala 207 predio 43312 Universidade Federal do Rio Grande do Sul 91501-970 Porto Alegre Brasil Department of Plant Biology Carnegie Institution for Science Stanford CA 94305 USA School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China Departamento de Botanica Universidade Federal do Rio Grande do Sul Porto Alegre Brasil Departamento de Genetica Universidade Federal do Rio de Janeiro Porto Alegre Brasil Centro de Biotecnologia Universidade Federal do Rio Grande do Sul Porto Alegre Brasil

Aluminum （AI） toxicity in plants is one of the primary constraints in crop production. Al3＋, the most toxic form of Al, is released into soil under acidic conditions and causes extensive damage to plants, especially in the roots. In rice, Al tolerance requires the ASR5 gene, but the molecular function of ASR5 has remained unknown. Here, we perform genome-wide analyses to identify ASR5-dependent Al-responsive genes in rice. Based on ASRS_RNAi silencing in plants, a global transcriptome analysis identified a total of 961 genes that were responsive to Al treatment in wildtype rice roots. Of these genes, 909 did not respond to Al in the ASR5_RNAi plants, indicating a central role for ASR5 in Al-responsive gene expression. Under normal conditions, without Al treatment, the ASR5 RNAi plants expressed 1.756 genes differentially compared to the wild-type plants, and 446 of these genes responded to AI treatment in the wild-type plants. Chromatin immunoprecipitation followed by deep sequencing identified 104 putative target genes that were directly regulated by ASR5 binding to their promoters, including the STAR1 gene, which encodes an ABC transporter required for AI tolerance. Motif analysis of the binding peak sequences revealed the binding motif for ASR5, which was confirmed via in vitro DNA-binding assays using the STAR1 promoter. These results demonstrate that ASR5 acts as a key transcription factor that is essential for AI-responsive gene expression and Al tolerance in rice.

关键词： Aluminum ChlP-Seq RNA-Seq rice ASR.