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Isochrone fitting of Galactic Globular Clusters—Ⅵ.High-latitude Clusters NGC 5024 (M53),NGC 5053,NGC 5272 (M3),NGC 5466,and NGC7099 (M30)

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Research in Astronomy and Astrophysics 2024年第6期24卷 170-190页

作者： G.A.Gontcharov S.S.Savchenko A.A.Marchuk C.J.Bonatto O.S.Ryutina M.Yu.Khovritchev v.B.Il'in A.v.Mosenkov D.M.Poliakov A.A.Smirnov Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1St.Petersburg 196140Russia Saint Petersburg State University Universitetskij pr.28St.Petersburg 198504Russia Special Astrophysical Observatory Russian Academy of Sciences369167 Nizhnij ArkhyzRussia Departamento de Astronomia Instituto de FísicaUFRGSAv.Bento Gonçalves9500Porto AlegreRSBrazil Saint Petersburg University of Aerospace Instrumentation Bol.Morskaya ul.67ASt.Petersburg 190000Russia Department of Physics and Astronomy Brigham Young UniversityN283 ESCProvoUT 84602USA

We fit various color–magnitude diagrams(CMDs) of the high-latitude Galactic globular clusters NGC 5024(M53),NGC 5053,NGC 5272(M3),NGC 5466,and NGC 7099(M30) by isochrones from the Dartmouth Stellar Evolution Database and Bag of Stellar Tracks and Isochrones for α–enrichment [α/fe] = +*** the CMDs,we use data sets from Hubble Space Telescope,Gaia,and other sources utilizing,at least,25 photometric filters for each *** obtain the following characteristics with their statistical uncertainties for NGC 5024,NGC 5053,NGC 5272,NGC 5466,and NGC 7099,respectively:metallicities [fe/H] =-1.93 ± 0.02,-2.08 ± 0.03,-1.60 ± 0.02,-1.95 ± 0.02,and-2.07 ± 0.04 dex with their systematic uncertainty 0.1 dex;ages 13.00 ± 0.11,12.70 ± 0.11,11.63 ± 0.07,12.15 ± 0.11,and 12.80 ± 0.17 Gyr with their systematic uncertainty 0.8 Gyr;distances(systematic uncertainty added) 18.22 ± 0.06 ± 0.60,16.99 ± 0.06 ± 0.56,10.08 ± 0.04 ± 0.33,15.59 ±0.03 ± 0.51,and 8.29 ± 0.03 ± 0.27 kpc;reddenings E(B-v) = 0.023 ± 0.004,0.017 ± 0.004,0.023 ± 0.004,0.023 ± 0.003,and 0.045 ± 0.002 mag with their systematic uncertainty 0.01 mag;extinctions Av= 0.08 ± 0.01,0.06 ± 0.01,0.08 ± 0.01,0.08 ± 0.01,and 0.16 ± 0.01 mag with their systematic uncertainty 0.03 mag,which suggest the total Galactic extinction Av= 0.08 across the whole Galactic dust to extragalactic objects at the North Galactic *** horizontal branch morphology difference of these clusters is explained by their different metallicity,age,mass-loss efficiency,and loss of low-mass members in the evolution of the core-collapse cluster NGC 7099 and loose clusters NGC 5053 and NGC 5466.

关键词： (stars:)Hertzsprung Russell and C-M diagrams (ISM:)dust extinction (Galaxy:)globular clusters:general (Galaxy:)globular clusters:individual(NGC 5024,NGC 5053,NGC 5272,NGC 5466,NGC7099)

Improving weld formability by a novel dual-rotation bobbin tool friction stir welding

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Journal of Materials Science & Technology 2018年第1期34卷 135-139页

作者： f.f.Wang W.Y.Li J.Shen Q.Wen J.f.dos santos State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding Technologies Northwestern Polytechnical University Helmholtz-Zentrum Geesthacht Institute of Materials Research Materials Mechanics China Academy of Launch vehicle Technology Beijing Institute of Astronautical Systems Engineering

A novel dual-rotation bobbin tool friction stir welding （DBT-fSW） was developed, in which the upper shoulder （US） and lower shoulder （LS） have different rotational speeds. This process was tried to weld 3.2 mm thick alunlinum-lithium alloy sheets. The metallographic analysis and torque measurement were carried out to characterize the weld formabiliW. Experimental results show that compared to conven- tional bobbin tool friction stir welding, the DBT-fSW has an excellent process stability, and can produce the defect-free joints in a wider range of welding parameters. These can be attributed to the significant improvement of material flow caused by the formation of a staggered layer structure and the unbalanced force between the US and LS during the DBT-fSW process.

关键词： Bobbin tool friction stir welding Dual rotation Material flow Microstructure Microhardness

Observation about the Classical Electromagnetic Gauge Transformation and Its Quantum Correspondence

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Journal of Modern Physics 2024年第4期15卷 474-479页

作者： Gustavo v. López Jorge A. Lizarraga Departamento de física Universidad de Guadalajara Guadalajara Mexico

Using the Landau and symmetric gauges for the vector potential of a constant magnetic field and the quantum problem of a charged particle moving on a flat surface, we show the classical electromagnetic gauge transformation does not correspond to a one-dimensional unitary group transformation U(1) of the wave function for the quantum case. In addition, with the re-examination of the relation between the magnetic field B and its vector potential A, we found that, in order to have a consistent formulation of the dynamics of the charged particle with both expressions, we must have that B=∇×A if and only if B≠0.

关键词： Gauge Transformation Harmonic Oscillator Quantum Hall Effect Electromagnetic Potentials

Effect of high anodic polarization on the passive layer properties of superduplex stainless steel friction stir welds at different chloride electrolyte pH values and temperatures

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 710-721页

作者： L.A.Santa-Cruz G.Machado A.A.vicente T.f.C.Hermenegildo T.f.A.santos Department of Mechanical Engineering Universidade Federal de PernambucoAv.da Arquiteturas/n50740-550RecifePEBrazil Center of Nanotechnology Centro de Tecnologias Estratégicas do NordesteCETENERecifePEBrazil Department of Chemical Engineering Universidade de Sao PauloSao PauloSPBrazil

The conditions used for friction stir welding of duplex stainless steels determine the resulting mechanical and corrosion performance of the *** study investigates the corrosion resistance of UNS S32750 and S32760 superduplex stainless steels(SDSSs)joined by friction stir welding,employing cyclic polarization,Mott–Schottky,and microscopy techniques for *** microscopy images indicated the presence of a deleterious intermetallic phase after electrolytic etching of S32760,as well as decreased corrosion *** presence of molybdenum in the steels promoted better passive behavior at low *** Mott–Schottky curves revealed p-n heterojunction behavior of the passive *** acquired after the polarization test by scanning electron microscopy showed higher passivation propensity with increases of temperature and pH.

关键词： superduplex stainless steel friction stir welding corrosion resistance cyclic polarization Mott–Schottky

vapor phase methylation of phenol on fe-substituted ZrO_2 catalyst

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Chinese Journal of Catalysis 2016年第11期37卷 1991-1996页

作者： Celia f.Braganza A.v.Salker 果阿大学化学系

fe-doped ZrO2 compounds were prepared by a co-precipitation *** compounds were characterized by X-ray diffraction,N2 adsorption-desorption,ultraviolet diffuse reflectance infrared fourier transform spectroscopy,scanning electron microscopy-energy-dispersive X-ray spectroscopy,transmission electron microscopy,NH3 temperature-programmed desorption,X-ray photoelectron spectroscopy,and in situ fourier transform infrared *** incorporation of fe into ZrO2 lattice favored and effectively stabilized the formation of purely ZrO2 tetragonal ***,the catalytic activity of the fe-doped ZrO2 compounds was evaluated toward vapor phase methylation of *** catalytic activity was governed by fe content and related to the Lewis acidity of the prepared catalyst.

关键词： Zirconia Iron doped Methylation Phenol Xylenol

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

The Use of Secondary Grape Biomass in Beef Cattle Nutrition on Carcass Characteristics, Quality and Shelf Life of Meat

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food and Nutrition Sciences 2024年第6期15卷 447-469页

作者： vitor L. Molosse Guilherme L. Deolindo Rafael v. P. Lago Bruna Klein Claiton A. Zotti Marcelo vedovato Marcylene v. da Silveira Priscila M. Copetti Maria R. C. Schetinger Juscivete f. favero Eliana L. fiorentin Aleksandro S. da Silva Universidade do Estado de Santa Catarina (UDESC) Chapec Brazil Department of Animal Science UDESC Chapec Brazil Department of Animal Science Universidade do Oeste de Santa Catarina Xanxere Brazil Dean Lee Research and Extension Center Louisiana State University Alexandria LA USA Department of Biochemistry Universidade Federal de Santa Maria Santa Maria Brazil Department of Medicina veterinria UNOCHAPEC Chapec Brasil

We determined whether the inclusion of 100 g/kg dry matter of grape pomace silage (GPS) and grape pomace bran (GPB) as substitutes for other traditional fiber sources in the diet of steers (Charolais x Nellore) would improve carcass characteristics, meat quality and composition, and shelf life. Twenty-four animals (248 ± 19.32 kg of initial body weight) were fed a high concentrate diet for 121 days. Carcass characteristics were measured, and the longissimus dorsi muscle was analyzed for fatty acid (fA) profile and composition. The meat was sliced and stored in air-permeable packages for 10 days. On each sampling day (d 1, 3, 7, and 10), oxidative stability, bacterial load, lipid and protein oxidation, and staining were analyzed. The experimental diets influenced the pH of cold carcasses only. The GPS group had a higher pH than the control. The GPS and GPB groups showed improved oxidant status (i.e., lower lipid peroxidation and concentrations of reactive oxygen species were in the meat of both groups than in control). On the first day of storage, the antioxidant enzyme glutathione S-transferase activity was more significant in the meat of the GPS and GPB groups than in the control. The bacterial loads in the meat were attenuated by GPS inclusion;there were lower total coliform counts and a trend toward lower counts for enterobacteria in the control group. The diets altered the fA profile of the meat;i.e., the GPB diet allowed for a more significant amount of the n-6 omegas in the meat, while the GPS diet showed a tendency for a more significant amount of n-6 and 9 omegas. Both diets (GPS and GPB) increased the amounts of long-chain fAs. The GPS diet decreased saturated fA levels. We conclude that the dietary treatments GPS and GPB are a promising alternative to maintain meat quality standards throughout in real-world retail conditions. These treatments gave rise to an improvement in the nutritional value of the meat due to the more significant amounts of fAs that im

关键词： Animal Nutrition Antioxidant Biomass Grape Meat Quality Microbiology Residue

Atrial fibrillation in the elderly

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Journal of Geriatric Cardiology 2012年第2期9卷 91-100页

作者： Roberto A. franken Ronaldo f. Rosa Silvio CM santos Department of Internal Medicine Santa Casa Sao Paulo Medical School R.Dr.Franco da Rocha 163/52 Sao Paulo 050l 5-040 Brazil Brazilian Society of Cardiology Rua Padre bartolomeu Tadei 18 Santos 11035-150 Brazil

This review discusses atrial fibrillation according to the guidelines of Brazilian Society of Cardiac Arrhythmias and the Brazilian Cardiogeriatrics Guidelines. We stress the thromboembolic burden of atrial fibrillation and discuss how to prevent it as well as the best way to conduct cases of atrial fibrillatios in the elderly, reverting the arrhythmia to sinus rhythm, or the option of heart rate control. The new methods to treat atrial fibrillation, such as radiofrequency ablation, new oral direct thrombin inhibitors and Xa factor inhibitors, as well as new antiarrhythmic drugs, are depicted.

关键词： Atrial fibrillation Heart failure Thrombo-embolism Treatment Prevention

Spouting behavior of binary particle mixtures of different densities: fluid dynamics and particle segregation

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Particuology 2019年第1期17卷 58-66页

作者： K.G. santos R.C. Santana D.L. Souza v.v. Murata M.A.S. Barrozo federal University ofTriangulo Mineiro Chemical Engineering DepartmentUniverdecidade CampusUberabaMGBrazil federal University of Uberlandia Chemical Engineering SchoolUberlandiaMG. Brazil

Numerous industrial applications of spouted beds involve a mixture of granular particles, where differences in particle size, density, and shape can cause particle segregation, affecting the quality of flow and decreasing product homogeneity. The aim of this study was to investigate the particle segregation and fluid dynamics of a conical spouted bed operating with a binary mixture of particles of different densities. Using glass beads and polyethylene particles with a diameter of 4 mm, we determined the effects of the mass fraction of denser particles and static bed height on the minimum spouting condition and mixture index. The pressure drop and airflow in the minimum spouting condition increased with an increase in bed height or jetsam concentration. Regarding particle segregation, the jetsam particles tended to concentrate near the bottom, at the spout–annulus interface because they have a shorter trajectory than the lighter particles in the fountain region. Jetsam-rich mixtures with high initial static bed heights exhibited more efficient particle mixing, excluding those at the bottom of the bed.

关键词： Density Segregation Spouted bed Binary mixtures