检索结果-南通市图书馆

Comparative case study of two methods to assess the eruptive potential of selected active regions

Research in Astronomy and Astrophysics 2021年第12期21卷 471-487页

作者： Francesca Zuccarello Ilaria Ermolli Marianna B.Korsós Fabrizio Giorgi salvo l.guglielmino Robertus Erdélyi Paolo Romano Dipartimento di Fisica e Astronomia"Ettore Majorana" Universitàdi CataniaVia S.Sofia 78195123 CataniaItaly INAF Osservatorio Astrofisico di Catania Via S.Sofia 781-95123 CataniaItaly INAF Osservatorio Astronomico di Roma Via Frascati 331-00078 Monte Porzio CatoneItaly Department of Physics Aberystwyth UniversityCeredigionCymruSY233BZUK Department of Astronomy E?tv?s Loránd UniversityPazmany P.setany 1/ABudapestH-l 117Hungary Solar Physics&Space Plasma Research Center(SP2RC) School of Mathematics and StatisticsUniversity of SheffieldHicks BuildingHounsfield RoadS37RHUK Gyula Bay Zoltán Solar Observatory(GSO) Hungarian Solar Physics Foundation(HSPF)etofi ter 3.GyulaH-5700Hungary

Solar eruptive events,like flares and coronal mass ejections,are characterized by the rapid release of energy that can give rise to emission of radiation across the entire electromagnetic spectrum and to an abrupt significant increase in the kinetic energy of *** energetic phenomena can have important effects on the space weather conditions and therefore it is necessary to understand their origin,in particular,what is the eruptive potential of an active region(AR).In these case studies,we compare two distinct methods that were used in previous works to investigate the variations of some characteristic physical parameters during the pre-flare states of flaring *** methods consider:i)the magnetic flux evolution and magnetic helicity accumulation,and ii)the fractal and multi-fractal properties of flux concentrations in *** comparative analysis is based on time series of photospheric data obtained by the Solar Dynamics Observatory between March 2011 and June *** selected two distinct samples of ARs:one is distinguished by the occurrence of more energetic M-and X-class flare events,that may have a rapid effect on not just the near-Earth space,but also on the terrestrial environment;the second is characterized by no-flares or having just a few C-and B-class *** found that the two tested methods complement each other in their ability to assess the eruptive potentials of ARs and could be employed to identify ARs prone to flaring *** on the presented case study,we suggest that using a combination of different methods may aid to identify more reliably the eruptive potentials of ARs and help to better understand the pre-flare states.

关键词： Sun:magnetic fields Sun:photosphere Sun:sunspots Sun:flares Sun:activity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

In situ microtomography investigation of microstructural evolution in Al-Cu alloys during holding in semi-solid state

引用

中国有色金属学会会刊：英文版 2010年第S3期20卷 734-738页

作者： S.TERZI l.salvo M.SUERY A.DAHlE E.BOllER Australian Research Council Centre of Excellence for Design in light Metals Materials EngineeringThe University of QueenslandBrisbane Queensland 4072Australia Université de Grenoble Science et Ingénierie des Matériaux et ProcédésGénie Physique et Mécanique des MatériauxUMR CNRS 5266Grenoble INPUniversité Joseph FourrierBP4638402 Saint-Martin d'Hères CedexFrance European Synchrotron Radiation Facility 6 rue Jules HorowitzBP22038043 Grenoble CedexFrance

The aim of this paper is to report the results of experiments carried out on Al-Cu alloys with different Cu contents,studying the microstructure evolution during holding in the semi-solid *** 3-D microstructure was observed by in situ X-ray microtomography carried out at ESRF Grenoble,*** variation of the solid-liquid interface area per unit volume during holding was *** addition,local observations show that two coarsening mechanisms of the solid particles occur simultaneously:dissolution of small particles to the benefit of larger ones by an Ostwald-type mechanism and the growth of necks between solid particles due to *** observations confirm that in situ X-ray tomography is a very powerful tool to study the microstructure evolution in the semi-solid state and the influencing mechanisms in real-time.

关键词： Al-Cu alloys microtomography remelting microstructure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Targeting Wnt signaling at the neuroimmune interface for dopaminergic neuroprotectionJrepair in Parkinson＇s disease

引用

Journal of Molecular Cell Biology 2014年第1期8卷 13-26页

作者： Francesca l'Episcopo Cataldo Tirolo salvo Caniglia Nuccio Testa Maria Concetta Moral~ Maria Francesca Serapide: Stefano Pluchino Bianca Marchetti OASI Institute for Research and Care on Mental Retardation and Brain Aging (IRCCS) Neuropharmacology Section Via Conte Ruggero 73 94018 Troina Italy Department of Physiolocal Sciences Medical School University of Catania Viale A. Doria 6 95125 Catania Italy Department of Clinical Neurosciences John van Geest Centre for Brain Repair and Wellcome Trust-Medical Research Counci~ Stem Celt Institute University ofCambridge Cambridge CB20PY UK Department of Clinical and Molecular Biomedicine Pharmacology Section Medical School University of Catania Viale A. Doria 6 95125 Catania Italy

During the past three decades, the Wingless-type MMTV integration site （Wnt） signaling cascade has emerged as an essential system regulating multiple processes in developing and adult brain. Accumulating evidence points to a dysregulation of Wnt signaling in major neurodegenerative pathologies including Parkinson＇s disease （PD）, a common neurodegenerative disorder characterized by the pro- gressive loss of midbrain dopaminergic （mDA） neurons and deregulated activation of astrocytes and microglia. This review highlights the emerging link between Wnt signaling and key inflammatory pathways during mDA neuron damage/repair in PD progression. In particular, we summarize recent evidence documenting that aging and neurotoxicant exposure strongly antagonize Wnt/β-catenin signaling in mDA neurons and subventricular zone （SVZ） neuroprogenitors via astrocyte-microglial interactions. Dysregulation of the crosstalk between Wnt/β-catenin signaling and anti-oxidant/anti-inflammatory pathways delineate novel mechanisms driving the decline of SVZ plasticity with age and the limited nigrostriatal dopaminergic self-repair in PD. These findings hold a promise in devetoping therapies that target Wnt/β-catenin signaling to enhance endogenous restoration and neuronal outcome in age-dependent diseases, such as PD.

关键词： Wnt/β-catenin signaling Parkinson's disease neuroinflammation dopaminergic neurons neurogenesis neurodegeneration neuroprotection

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Improvements in tribological and anticorrosion performance of porous Ti–6Al–4V via PEO coating

引用

Friction 2021年第5期9卷 1303-1318页

作者： C.Garcia-Cabezón M.l.Rodríguez-Méndez V.AmigóBorrás R.Bayón C.salvo-Comino C.Garcia-Hernandez F.Martin-Pedrosa Materials Engineering E.I.I.Universidad de ValladolidValladolid 47011Spain BioecoUVA Research Institute Universidad de ValladolidValladolid 47011Spain Group UVASENS Escuela de Ingenierías IndustrialesUniversidad de ValladolidValladolid 47011Spain Instituto de Tecnología de Materials Univesitat Politécnica de ValenciaValencia 46022Spain Tribology Unit Fundación IK4-TeknikerEibar 20600Spain

Medical implants manufactured using biomaterial Ti–6Al–4V exhibit some *** higher elastic modulus than that of natural bone can cause stress shielding *** can be avoided using Ti–6Al–4V with pores in the implant ***,poor corrosion and tribocorrosion behaviors are yielded because of the large area exposed to the *** mitigate both issues,coating technologies can be *** plasma electrolytic oxidation(PEO)process is a cost‐effective process that has been used successfully in nonporous Ti *** this study,two PEO coatings with different amounts of Ca/P are ***,reports regarding their application in porous materials are *** effects of PEO treatments on corrosion and tribocorrosion in Ti–6Al–4V powder metallurgy are analyzed *** porous materials provide an efficient surface for PEO coatings,as demonstrated via scanning electron microscopy(SEM)and atomic force microscopy(AFM),and the porosity of the substrates improved the adherence of the *** corrosion resistance measured via electrochemical impedance spectroscopy confirmed the beneficial effect of the coatings,particularly for long exposure *** lower roughness,small pore size,and more compact film observed in the PEO–Ca/P sample resulted in favorable tribological and corrosion properties.

关键词： Ti‐based alloys corrosion tribocorrosion surface modification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Updating the orbital ephemeris of the dipping source XB 1254–690 and the distance to the source

引用

Research in Astronomy and Astrophysics 2017年第10期17卷 97-108页

作者： Angelo F.Gambino Rosario Iaria Tiziana Di salvo Marco Matranga luciano Burderi Fabio Pintore Alessandro Riggio Andrea Sanna Universita degli Studi di Palermo Dipartimento di Fisica e Chimica Universita degli Studi di Cagliari Dipartimento di Fisica INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica - Milano

XB 1254-690 is a dipping low mass X-ray binary system hosting a neutron star and showing type I X-ray bursts. We aim at obtaining a more accurate orbital ephemeris and at constraining the orbital period derivative of the system for the first time. In addition, we want to better constrain the distance to the source in order to locate the system in a well defined evolutive scenario. We apply, for the first time, an orbital timing technique to XB 1254-690, using the arrival times of the dips present in the light curves that have been collected during 26 yr of X-ray pointed observations acquired from different space missions. We estimate the dip arrival times using a statistical method that weights the count-rate inside the dip with respect to the level of persistent emission outside the dip. We fit the obtained delays as a function of the orbital cycles both with a linear and a quadratic function. We infer the orbital ephemeris of XB 1254-690, improving the accuracy of the orbital period with respect to previous estimates. We infer a mass of M2 = 0.42 ± 0.04 M for the donor star, in agreement with estimations already present in literature, assuming that the star is in thermal equilibrium while it transfers part of its mass via the inner lagrangian point, and assuming a neutron star mass of 1.4 Mo. Using these assumptions, we also constrain the distance to the source, finding a value of 7.6±0.8 kpc. Finally, we discuss the evolution of the system, suggesting that it is compatible with a conservative mass transfer driven by magnetic braking.

关键词： stars: neutron -- stars: individual (XB 1254-690) -- X-rays: binaries -- X-rays: stars --Astrometry and celestial mechanics: ephemerides

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

低相位噪声倍频微波源

引用

宇航计测技术 1985年第S1期 80-85页

作者： J.T.Haynes H.salvo 杨容芳

使用高次泛音体声波谐振器(HBAR),可能研制出直接工作在微波频率的低相位噪声倍频微波源。最近,已研制出一个l波段的低噪声源,它能提供约以5MHz为间隔的信号,并能得到与低频石英晶体稳定和倍频的微波源相同的相位噪声抑制度,高次泛音体... 详细信息

使用高次泛音体声波谐振器(HBAR),可能研制出直接工作在微波频率的低相位噪声倍频微波源。最近,已研制出一个l波段的低噪声源,它能提供约以5MHz为间隔的信号,并能得到与低频石英晶体稳定和倍频的微波源相同的相位噪声抑制度,高次泛音体声波谐振器(HBAR)直接倍频到微波源需要少量硬件,以达到用任何其它方法得到倍频微波源所具有的相同的相位噪声抑制度。稳定的工作是通过利用钇铝石榴石(YAG)、蓝宝石、铌酸锂式铝酸锂等晶体的高次泛音谐振来达到的。它们的固有损耗表明,其潜在Q值近似为石英晶体的十倍。已制成的这种谐振器的频率高达10GHz。对1.5GHz频段的压缩模式,已在几个样品中得到50,000以上的有载Q值。这些谐振器由其晶片上渡漠换能器组成。单纯的反射被限制在换能器之下区域内。晶体牢牢地被装在外壳中,以尽量减小外部振动对频率稳定度的影响。测量振动灵敏度的情况在一篇参考文献中简述。此倍频微波源包括一个用自动频率控制(AFC)回路稳定的低噪声压控振荡器(VCO)。在自动频率控制(AFC)鉴频器中,高次泛音体声波谐振器是决定频率的元件。测量的相位噪声与估计的性能很一致。本文提供了噪声特性的详细情况。用附加的数字控制电路将压控振荡器予调到高次泛音体声波谐振器(HBAR)的任一次响应上,可以很容易地实现倍频。因此,用最少的硬件得到了低相位噪声用电子方法控制的倍频源。

关键词：低相位噪声调幅噪声压控振荡器倍频源体声波谐振器微波源泛音奏法

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Meta分析方法系统性分析腹腔镜疝修补术的选择——TEP与TAPP

引用

中华疝和腹壁外科杂志（电子版） 2013年第4期7卷 79-80页

作者： Bracale U Melillo P Pignata G Di salvo E Rovani M Merola G Pecchia l Surg Endosc 陈大伟上海交通大学医学院附属新华医院崇明分院普外科 202150

腹股沟疝修补术是最常见的手术之一。一个好的疝修补术应该是操作简单、手术时间短、安全。手术结果必须是创伤小、疼痛轻以及复发率低口j。腹腔镜疝修补术和传统的开放式疝修补术（openherniarepair，OHR）相比，术后疼痛轻、对患者限... 详细信息

腹股沟疝修补术是最常见的手术之一。一个好的疝修补术应该是操作简单、手术时间短、安全。手术结果必须是创伤小、疼痛轻以及复发率低口j。腹腔镜疝修补术和传统的开放式疝修补术（openherniarepair，OHR）相比，术后疼痛轻、对患者限制少。目前，在临床上使用最多的腹腔镜疝修补术方法分别是：经腹腔腹膜前疝修补（transabdominalpreperitoneal，TAPP）和完全腹膜外疝修补（totallyextraperitonealherniarepair，TEP）。本文运用随机对照法研究资料，分析TEP与TAPP孰优孰劣。

关键词：腹腔镜疝修补术 Meta分析方法 TAPP TEP 系统性分析腹股沟疝修补术手术时间术后疼痛

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

latest results from GRAAl collaboration

引用

Chinese Physics C 2009年第12期33卷 1249-1253页

作者： V. Vegna V. Bellini J.P. Bouquet l. Casano A. D'Angelo J.P. Didelez R. Di salvo A. Fantini D. Franco G. Gervino F. Ghio G. Giardina B. Girolami A. Giusa M. Guidal E. Hourany A.S. Ignatov R. Kunnel A. lapik A. lleres P. levi Sandri F. Mammoliti G. Mandaglio M. Manganaro M. Moricciani A.N. Mushkarenkov V.G. Nedorezov C. Randieri D. Rebreyend N.V. Rudnev G. Russo C. Schaerf M.l. Sperduto M.C. Sutera A.Turinge Dip. di Fisica Università degli Studi di Roma 'Tor Vergata' via della Ricerca Scientifica 1 I-00133 Roma Italy INFN - Sezione di Roma 'Tor Vergata' via della Ricerca Scientifica 1 I-00133 Roma Italy Dip. di Fisica e Astronomia Università di Catania via Santa Sofia 44 I-95123 Catania Italy INFN - Sezione di Catania via Santa Sofia 44 I-95123 Catania Italy lPSC Universit Joseph Fourier Grenoble 1 CNRS/IN2P3 Institut National Polytechnique de Grenoble 53 Avenue des Martyres 38026 Grenoble France IPNO Universit de Paris-Sud 11 CNRS/IN2P3 15 rue Georges Clemenceau 91406 Orsay France Dip. di Fisica Sperimentale Università di Torino via P.Giuria I-00125 Torino Italy INFN - Sezione di Torino via P.Giuria I-00125 Torino Italy Istituto Superiore di Sanità viale Regina Elena 299 I-00161 Roma Italy INFN - Sezione di Roma piazzale Aldo Moro 2 I-00185 Roma Italy Dip. di Fisica Universitàdi Messina salita Sperone 31 I-98166 Messina Italy Institute for Nuclear Research RAS 117312 Moscow Russia INFN - laboratori Nazionali di Frascati via E.Fermi 40 I-00044 Frascati Italy INFN - Sezione di Catania via Santa Sofia 44 I-95123 Catania Italy

The GRAAl experimental set-up consists of a polarized and tagged photon beam that covers an energy range from a minimum of 600 MeV up to a maximum of 1500 MeV, of a liquid Hydrogen or Deuterium target and of the 4π lagrange detector optimized for photon detection. It allows the study of pseudo-scalar and vector meson photoproduCtion on the nucleon in the energy range corresponding to the second and the third resonance regions. In the following, the ∑ beam asymmetries in η and π0 photoproduction on quasi-free nucleon are shown. Also single and double polarization observables in K＋A photoproduction on free proton are shown; they are important to confirm the role of new or poorly known resonances in the 1900 MeV mass region.

关键词： polarized photon meson photoproduction polarization observables

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

踝关节创伤后关节炎的相关危险因素:一项随访18年的回顾性研究

引用

中国矫形外科杂志 2012年第18期20卷 1652-1652页

作者： lübbeke A salvo D Stern R Hoffmeyer P Holzer N Assal M. 于涛俞光荣同济大学附属同济医院骨科

踝关节创伤后关节炎十分常见，其发生率比髋膝关节高得多，而目前对其危险因素评估的长期随访研究报道很少。作者对1988年1月-1997年12月的373例进行切开复位内固定的踝关节骨折进行了回顾性研究，并进行统计学分析。Pilon骨折、距骨骨... 详细信息

踝关节创伤后关节炎十分常见，其发生率比髋膝关节高得多，而目前对其危险因素评估的长期随访研究报道很少。作者对1988年1月-1997年12月的373例进行切开复位内固定的踝关节骨折进行了回顾性研究，并进行统计学分析。Pilon骨折、距骨骨折及年龄〈18岁者未纳入研究。

关键词：相关危险因素踝关节骨折随访研究关节炎创伤后切开复位内固定 Pilon骨折统计学分析

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dense matter with eXTP

引用

Science China(Physics,Mechanics & Astronomy) 2019年第2期62卷 28-44页

作者： Anna l.Watts WenFei Yu Juri Poutanen Shu Zhang Sudip Bhattacharyya Slavko Bogdanov long Ji Alessandro Patruno Thomas E.Riley Pavel Bakala Altan Baykal Federico Bernardini Ignazio Bombaci Edward Brown Yuri Cavecchi Deepto Chakrabarty Jér?me Chenevez Nathalie Degenaar Melania Del Santo Tiziana Di salvo Victor Doroshenko Maurizio Falanga Robert D.Ferdman Marco Feroci Angelo F.Gambino MingYu Ge Svenja K.Greif Sebastien Guillot Can Gungor Dieter H.Hartmann Kai Hebeler Alexander Heger Jeroen Homan Rosario Iaria Jean in 't Zand Oleg Kargaltsev Aleksi KurkelaTheoretical Physics Department CERN XiaoYu lai Ang li XiangDong li ZhaoSheng li Manuel linares FangJun lu Simin Mahmoodifar Mariano Méndez M.Coleman Miller Sharon Morsink Joonas N?ttil? Andrea Possenti Chanda Prescod-Weinstein Jinlu Qu Alessandro Riggio Tuomo Salmi Andrea Sanna Andrea Santangelo Hendrik Schatz Achim Schwenk liMing Song Eva?rámková Benjamin Stappers Holger Stiele Tod Strohmayer Ingo Tews laura Tolos Gabriel T?r?k David Tsang Martin Urbanec Andrea Vacchi RenXin Xu YuPeng Xu Silvia Zane GuoBao Zhang ShuangNan Zhang WenDa Zhang ShiJie Zheng Xia Zhou Anton Pannekoek Institute for Astronomy University of Amsterdam Shanghai Astronomical Observatory Tuorla Observatory Department of Physics and Astronomy University of Turku Nordita KTH Royal Institute of Technology and Stockholm University Institute of High Energy Physics Chinese Academy Sciences Tata Institute of Fundamental Research Columbia Astrophysics laboratory Columbia University Institut für Astronomie und Astrophysik Tübingen Universit?t Tübingen leiden Observatory Leiden University Research Center for Computational Physics and Data Processing Silesian University in Opava Physics Department Middle East Technical University INAF Osservatorio Astronomico di Roma New York University Abu Dhabi Dipartimento di Fisica Enrico Fermi University of Pisa INFN Italian National Institute for Nuclear Physics Department of Physics and Astronomy Michigan State University Department of Astrophysical Sciences Princeton University Mathematical Sciences and STAG Research Centre University of Southampton MIT Kavli Institute for Astrophysics and Space Research DTU Space Technical University of Denmark INAF/IASF Palermo via Ugo La Malfa 153 Universita degli Studi di Palermo Dipartimento di Fisica e Chimica International Space Science Institute (ISSI) Faculty of Science University of East Anglia INAF Istituto di Astrofisica e Planetologie Spaziali Institut für Kernphysik Technische Universit?t Darmstadt ExtreMe Matter Institute EMMI GSI Helmholtzzentrum für Schwerionenforschung GmbH Instituto de Astrof'?sica Pontificia Universidad Católica de Chile Department of Physics & Astronomy Kinard Lab of Physics Clemson University School of Physics and Astronomy Monash University SRON Netherlands Institute for Space Research Department of Physics The George Washington University Faculty of Science and Technology University of Stavanger School of Physics and Mechanical & Electrical Engineering Hubei University of Education Department of Astronomy Xiamen University (Haiyun Campus) School of Astronomy and Space

In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry(eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy Physics of the Chinese Academy of Sciences, the eXTP mission is expected to be launched in the mid 2020 s.

关键词： neutron X-rays dense matter equation of state

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：