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Subpulse Drifting of PSR j1110–5637

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Research in Astronomy and Astrophysics 2022年第6期22卷 109-117页

作者： S.j.Dang L.H.Shang L.Lin Q.j.Zhi R.S.Zhao C.B.Wu Z.Y.You A.j.Dong j.T.Bai X.Xu D.D.Zhang H.Yang Q.W.Lin School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China School of Physics Science and Technology Xinjiang UniversityUrumqi 830011China

We report a detailed study of polarization characteristics and subpulse drifting in PSR j1110-5637 with the observations of the Parkes 64 m radio telescope at 1369 *** observations revealed that the trailing component of the pulse profile has obvious subpulse drifting,while the leading component has no subpulse *** the two-dimensional fluctuation spectrum(2DFS),we detected three distinct emission modes in the trailing component(modes A,B and C).The emission in mode A is chaotic and indistinguishable,while modes B and C have obvious subpulse *** vertical modulation periods P3of modes B and C are around the mean values of 12 P and 8 P,*** subpulse drifting of PSR j1110-5637 will expand the pulsar sample with multiple subpulse drifting rates,and this will help future systematic studies on the physical origin of the subpulse drifting phenomenon.

关键词： (stars:)pulsars general-(stars:)pulsars individual(PSR j1110-5637)-Stars

General aspects on structural integrity

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Chinese journal of Aeronautics 2019年第1期32卷 114-132页

作者： j.j.XIONG R.A.SHENOI School of Transportation Science and Engineering Beihang University Faculty of Engineering and Environment University of Southampton

This paper seeks to mark the fruitful collaborative research between scholars in the University of Southampton and Beihang University for last 25 years on structural integrity. Their efforts addressed some important issues in structural integrity such as fatigue and fracture behavior,fatigue load spectra, fatigue and fracture lifetimes, reliability-based service period, adhesively bonded composite patch repairs, Plain Woven Fabric(PWF) composites and composite *** advances in engineering approaches, experimental methods, numerical algorithms and understanding of failure mechanisms relating to structural integrity are highlighted. Probable limits(or drawbacks) are also discussed. This review provides an insight into the general aspects on structural integrity and constitutes a basis for pointers to the further works on structural integrity.

关键词： Composites Fatigue Fracture Reliability Repair Structural integrity

Land-use change and windstorms legacies drove the recolonization dynamics of laurel forests in Tenerife, Canary islands

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Forest Ecosystems 2023年第1期10卷 113-124页

作者： Vicente Rozas Maria A.Garcia-Lopez jose M.Olano Gabriel Sanguesa-Barreda Miguel Garcia-hidalgo Susana Gomez-Gonzalez Roberto Lopez-Rubio jose M.Fernandez-Palacios Ignacio Garcia-Gonzalez Laura Lozano-Lopez Paula Garcia-Gonzalez Ana I.Garcia-Cervigon EiFAB-iuFOR Universidad de ValladolidCampus Duques de Soria42004SoriaSpain Departamento de Biologia-IVAGRO Universidad de CadizCampus Rio San Pedro11510Puerto RealSpain Center for Climate and Resilience Research(CR)2 Blanco Encalada 20028370449SantiagoChile Area de Biodiversidad y Conservacion Universidad Rey Juan Carlosc/Tulipan s/n28933MostolesSpain Grupo de Ecologia y Biogeografia Insular Universidad de La Laguna38206La LagunaTenerifeSpain BIOAPLIC Departamento de BotanicaEscola Politecnica Superior de EnxenariaCampus TerraUniversidade de Santiago de CompostelaLugo27002Spain

Laurel forests are quite relevant for biodiversity conservation and are among the island ecosystems most severely damaged by human *** the past,Canary laurel forests have been greatly altered by logging,livestock and *** remains of laurel forests are currently protected in the Canary Islands(Spain).However,we miss basic information needed for their restoration and adaptive management,such as tree longevity,growth potential and responsiveness to natural and anthropogenic *** dendrochronological methods,we studied how forest dynamic is related to land-use change and windstorms in two well-preserved laurel forests on Tenerife *** cores were collected from over 80 trees per stand at three stands per *** used ring-width series to estimate tree ages and calculate annual basal area increments(BAI),cumulative diameter increases,and changes indicative of released and suppressed *** tree species were found in all stands,with Laurus novocanariensis,Ilex canariensis and Morella faya being the most common *** some individuals were over 100 years old,61.8%-88.9% of the trees per stand established between 1940 and 1970,coinciding with a post-war period of land abandonment,rural exodus and the onset of a tourism *** trees have shown growth rates larger than 1 cm diameter per year and most species have had increasing BAI trends over the past *** growth releases occurred after windstorms at both sites,but the effects of windstorms were site-dependent,with the 1958 storm affecting mainly the eastern tip of the island(Anaga massif)and the 1991 storm the western tip(Teno massif).Given the great ability of laurel forest trees to establish after land use cessation and to increase growth after local disturbances such as windstorms,passive restoration may be sufficient to regenerate this habitat in currently degraded areas.

关键词： Canary islands Dendroecology Disturbance Forest structure Macaronesia Management cessation Tree rings

Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research International 2022年第5期29卷 819-835页

作者： j.L.Guo T.j.Chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were *** results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more *** softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface *** vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing *** is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is *** behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

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厄瓜多尔安巴托法院

设计 2017年第8期30卷 30-31页

作者： jacob sebastián crespo(图)

这是厄瓜多尔国家政府司法系统重组的一部分，建设新法院的宗旨是“保证所有公民都有及时的、高效、质量的途径接近正义。”项目是紧急委托建设，这就意味着设计项目的时间被大幅度减少，并且需要对于常规的设计流程进行重新规划。每个... 详细信息

这是厄瓜多尔国家政府司法系统重组的一部分，建设新法院的宗旨是“保证所有公民都有及时的、高效、质量的途径接近正义。”项目是紧急委托建设，这就意味着设计项目的时间被大幅度减少，并且需要对于常规的设计流程进行重新规划。每个建筑都是由独立的承包商完成，并和设计团队没有任何关联。

关键词：厄瓜多尔法院设计项目系统重组设计流程承包商

A study on distributive and modular lattice ordered fuzzy soft group and its duality

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Applied Mathematics(A journal of Chinese Universities) 2016年第4期31卷 491-502页

作者： j Arockia Reeta j Vimala Department of Mathematics Alagappa University

Soft set theory has a rich potential application in several fields. A soft group is a parameterized family of subgroups and a fuzzy soft group is a parameterized family of fuzzy subgroups. The concept of fuzzy soft group is the generalization of soft group. Abdulkadir Aygunoglu and Halis Aygun introduced the notion of fuzzy soft groups in 2009[1]. In this paper, the concept of lattice ordered fuzzy soft groups and its duality has been introduced. Then distributive and modular lattice ordered fuzzy soft groups are analysed. The objective of this paper is to study the lattice theory over the collection of fuzzy soft group in a parametric manner. Some pertinent properties have been analysed and hence established duality principle.

关键词： Fuzzy soft set fuzzy soft group lattice ordered fuzzy soft groups distributive lattice orderedfuzzy soft groups modular lattice ordered fuzzy soft groups.

Influence of Early Life Stress on Alcohol and Crack Dependents

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Open journal of Nursing 2020年第5期10卷 490-512页

作者： Elton Brás Camargo júnior Maria Neyrian de Fátima Fernandes Larissa Bessani hidalgo Gimenez jaqueline Rodrigues Stefanini Ana Carolina Guidorizzi Zanetti Edilaine Cristina da Silva Gherardi-Donato Department of Psychiatric Nursing and Human Sciences College of Nursing University of São Paulo Ribeirão Preto Brazil Department of Nursing University of Rio Verde Rio Verde Brazil Department of Nursing Coordination University Federal of Maranhão Imperatriz Brazil Department of Nursing Coordination Faculdade Unida of Campinas (FACUNICAMPS) Gôiania Brazil

Background: Early life stress is a significant public health problem associated with increased rates of psychiatric disorders, especially those related to drug abuse. Objective: To identify the prevalence of early life stress in drug users, to compare the intensity of trauma in alcohol and crack users, and to relate the power of injury to the severity of drug dependence. Method: Cross-sectional analytical study with a sample of 105 alcohol and crack users treated by an outpatient service. The instruments for data collection were sociodemographic data questionnaire, the Mini-International Neuropsychiatric Interview, and the Severity of Dependence Scale. The categorical variables association was analyzed using the Chi-squared test, considering p Results: High prevalence of early stress and severity of dependence were identified, with higher rates among crack users. The early stress revealed in the Alcohol group high rates of emotional (88.7%) and physical (94.3%) neglect and in the Crack group significant frequency of physical (61.5%) emotional abuse (51.9%), sexual (46.2%), and emotional (78.8%) and physical (90.4%) neglect. Crack users are 2.6 times more likely to have been emotionally abused, and 2.1 times more likely to have been sexually abused during childhood when compared to the alcohol group. Conclusion: Early stress was prevalent with significant intensity in drug users, and evaluation of this problem is essential for a better understanding of these disorders.

关键词： Childhood Trauma Adverse Childhood Experiences Child Abuse Early Life Stress Substance Abuse Crack Alcohol

Accuracy details in realistic CFD modeling of an industrial centrifugal pump in direct and reverse modes

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journal of Thermal Science 2010年第6期19卷 491-499页

作者： j.C. Páscoa F. j. Silva j.S. Pinheiro D.j. Martins Department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EFAFLU Bombas e Ventiladores S.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subject to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. Conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using Spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. Further computations are presented for the pump working in reverse turbine mode (PAT). Detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling Spalart-Allmaras PAT

Effects of the Reversely Rotating Assisted Shoulder on Microstructures During the Reverse Dual-rotation Friction Stir Welding

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journal of Materials Science & Technology 2015年第4期31卷 375-383页

作者： j.Q.Li H.j.Liu State Key Laboratory of Advanced Welding and joining Harbin Institute of Technology Capital Aerospace Machinery Company

The reverse dual-rotation friction stir welding(RDR-FSW) has the capability to adjust the heat generation because of the separately designed tool shoulder and tool *** welding torque exerted on the workpiece by the reversely rotating shoulder is opposite to that exerted by the rotating tool pin,so the total welding torque is reduced,which is beneficial to reducing the clamping requirement of *** the present paper,a RDR-FSW joint was welded in a condition similar to the optimal welding condition of conventional FSW,and microstructures in various zones were investigated by comparison,aiming to highlight effects of the reversely rotating assisted *** to the heat conduction of the middle cylinder and the bottom end cover on which the assisted shoulder was machined,the thermal effect of RDR-FSW was smaller than that of the conventional ***,the effect of assisted shoulder on the plastic flow or deformation of material or was constrained in a thin layer near the weld top surface,and thus the flow of material especially along the thickness direction was clearly decreased in the *** the heat-affected zone(HAZ),the precipitate coarsening was the main evolution and was completed through the dissolution of small precipitates and the continuous growth of large *** contrast,the dissolution degree of precipitates increased significantly in the thermomechanically affected zone(TMAZ),and a small amount of original meta-stable precipitates transformed to block-shaped stable *** evolutions in the shoulder affected zone(SAZ)and the weld nugget zone were similar,*** majority of original meta-stable precipitates dissolved into the matrix and the remainder transformed to stable precipitates,though the dissolution degree was greater in the *** with the conventional FSW joint,the coarsening degrees of precipitates in the HAZ and TMAZ of RDR-FSW joint were much smaller,as well as the dissolution degrees of p

关键词： Friction stir welding Reverse dual-rotation fricti