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Candidate Eclipsing Binary Systems with a δ Scuti Star in Northern TESS field

Research in Astronomy and Astrophysics 2022年第8期22卷 36-50页

作者： f.Kahraman Ali?avu? D.Gümü? ?.K?rm?z?ta? ?.Ekinci S.?avu? Y.T.Kaya f.Ali?avu? ?anakkale Onsekiz Mart University Faculty of Sciences and Arts Physics Department ?anakkale Onsekiz Mart University Astrophysics Research Center and Ulupnar Observatory Istanbul University Institute of Graduate Studies in Science Programme of Astronomy and Space Sciences ?anakkale Onsekiz Mart University School of Graduate Studies Department of Physics ?anakkale Onsekiz Mart University School of Graduate Studies Department of Space Sciences and Technologies ?anakkale Onsekiz Mart University Faculty of Engineering Computer Engineering

The existence of pulsating stars in eclipsing binaries has been known for decades. These types of objects are extremely valuable systems for astronomical studies as they exhibit both eclipse and pulsation variations. The eclipsing binaries are the only way to directly measure the mass and radius of stars with a good accuracy(≤1%),while the pulsations are a unique way to probe the stellar interior via oscillation frequencies. There are different types of pulsating stars existing in eclipsing binaries. One of them is the δ Scuti variables. Currently, the known number of δ Scuti stars in eclipsing binaries is around 90 according to the latest catalog of these variables. An increasing number of these kinds of variables is important to understand the stellar structure, evolution and the effect of binarity on the pulsations. Therefore, in this study, we focus on discovering new eclipsing binaries with δ Scuti component(s). We searched within the northern Transiting Exoplanet Survey Satellite(TESS) field with a visual inspection by following some criteria such as light curve shape, the existence of pulsation like variations in the out-of-eclipse light curve and the Teffvalues of the targets. As a result of these criteria, we discovered some targets. The orbital variations were first removed from the TESS light curves and frequency analysis was performed on the residuals. The luminosity, and absolute and bolometric magnitudes of the targets were calculated as well. To find how much of these parameters represent the primary(more luminous) binary component, we also computed the flux density ratio of the systems by utilizing the area of the eclipses. In addition, the positions of the systems in the H-R diagram were examined considering the flux density ratios. As a consequence of the investigation, we defined 38 candidate δ Scuti stars and also one Maia variable in eclipsing binary systems.

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Research advances on internal processes affecting tropical cyclone intensity change from 2018–2022

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Tropical Cyclone Research and Review 2023年第1期12卷 10-29页

作者： Xiaomin Chen Christopher M.Rozoff Robert f.Rogers Kristen l.Corbosiero Dandan Tao Jian-feng Gu falko Judt Eric A.Hendricks Yuqing Wang Michael M.Bell Daniel P.Stern Kate D.Musgrave John A.Knaff John Kaplan NOAA/OAR/Atlantic Oceanographic and Meteorological laboratory MiamiUSA University of Alabama in Huntsville HuntsvilleUSA National Center for Atmospheric Research BoulderUSA University at Albany/State University of New York AlbanyUSA University of Bergen BergenNorway Nanjing University NanjingChina University of Reading ReadingUK University of Hawaii at Manoa HonoluluUSA Colorado State University Fort CollinsUSA University Corporation for Atmospheric Research MontereyUSA NOAA Center for Satellite Applications and Research Fort CollinsUSA Department of Atmospheric and Earth Science University of Alabama in HuntsvilleHuntsvilleUSA

This contribution summarizes the significant progress in a variety of topic areas related to internal tropical cyclone(TC)intensity change processes over 2018–2022 from the WMO Tenth International Workshop on Tropical Cyclones(IWTC-10).These topic areas include surface and boundary layer processes;TC internal structure and microphysical processes;and,radiation interactions with *** studies better frame the uncertainty in the surface drag and enthalpy coefficients at high wind *** parameters greatly impact TC intensity and it is therefore important that more direct measurements of these boundary layer parameters are *** significant scientific strides have been made in TC boundary *** advancements have been achieved through improved coupled models,large-eddy simulations,theoretical advance-ments,and detailed *** is now clear that the research field needs to better represent the eddy viscosity throughout the depth of the boundary ***,detailed study of coherent structures in TC boundary layers will likely be a propitious direction for the research ***,in-depth observational field campaigns and assiduous data analysis have made significant headway into verifying theory and modeling studies of intensification processes related to TC vortex alignment,efficient latent heating distributions,and overall 3D *** efforts have also been made to better understand the intricate roles radiative processes play in TC evolution and intensity ***,some promising progress has been made in the development of time-dependent theories of TC intensification and the predictability of internal TC intensity ***,there have been well-earned gains in the understanding of intensity change processes intrinsic to the TC system,but the journey is not *** paper highlights some of the most relevant and important research areas that are still shedding new light into internal fa

关键词： Tropical cyclone Intensity Internal dynamics Boundary-layer processes Observations Predictability

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Tensile and cyclic deformation response of friction-stir-welded dissimilar aluminum alloy joints:Strain localization effect

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Journal of Materials Science & Technology 2021年第14期73卷 91-100页

作者： P.l.Niu W.Y.li D.l.Chen State Key laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi'an710072.China Department of Mechanical and Industrial Engineering Ryerson University350 Victoria StreetTorontoOntarioM5B2K3Canada

Cyclic deformation behavior of friction-stir-welded dissimilar AA2024-T351 to AA7075-T65 aluminum alloy joints was evaluated via stepwise tests at different strain rates,along with transmission electron microscopy examinations to characterize the precipitates required to assess internal *** backscatter diffraction was employed to observe the inhomogeneous microstructures of the fSWed *** localization appeared in the heat affected zone(HAZ)of AA2024 *** cyclic deformation of 500 cycles at a total strain amplitude of 0.5%,the strength of the dissimilar joints resumed basically to that of AA2024 base *** the AA2024 HAZ was obviously hardened,which should be attributed to the introduced dislocations during cyclic deformation *** hardening capacity of the joints increased with decreasing strain rate.

关键词： friction stir welding Dissimilar aluminum alloys Strain localization Cyclic hardening Slip irreversibility

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Spatiotemporal spectrum and momentum flux of the stratospheric gravity waves generated by a typhoon

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Science China Earth Sciences 2013年第5期56卷 54-62页

作者： CHEN Dan CHEN ZeYu lü DaRen Key laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences College of Atmospheric Sciences Nanjing University of Information Science & Technology

The simulation results of Typhoon Matsa (2005) by using the Weather Research and forecasting (WRf) model show that pronounced stratospheric gravity waves (GWs) are generated in the vicinity of the typhoon. Using the model output, we investigate the spatial structures and the temporal variations of the GWs through a three dimensional (3-d) spectral analysis, i.e. the spectrum with respect to two horizontal wavenumbers and frequency. We further derive the momentum flux carried by the GWs. Spectral investigation results show that the power spectral density (PSD) of the GWs exhibits a single-peaked spectrum, which consists primarily of a distinct spectrum at horizontal wavelength of ~1000km, time period of 12-18h, and vertical wavelength of 7-9km. This spectrum is different from the spectra of GWs generated by deep convections disclosed by the previous researches. Both the PSD and momentum flux spectrum are prominent in positive k h portion, which is consistent with the fact that the GWs propagate in the upstream of mean flow. large momentum flux is found to be associated with the GWs, and the net zonal momentum flux is 0.7845×10 3 Pa at 20km height, which can account for ~26% of the momentum flux that is required in driving the QBO phenomenon.

关键词：动量通量平流层台风引力波时空频谱分析模型显示时间变化

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骨形态发生蛋白7通过下调Ajuba减轻糖尿病肾病大鼠肾纤维化

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中国病理生理杂志 2024年第1期40卷 110-117页

作者：冯昭卫代云莉梁丹李志阳王一凡吕厚星陈佳佳陈圣杰郭兵肖瑛贵州省常见慢性疾病发病机制及药物研究重点实验室贵州贵阳550025 贵州医科大学病理生理学教研室贵州贵阳550025

目的:探讨在糖尿病肾病(DKD)大鼠模型中,骨形态发生蛋白7(BMP7)是否通过下调Ajuba水平,降低Yes相关蛋白1(YAP1)的表达,进而减轻细胞外基质(ECM)沉积从而减轻DKD大鼠肾组织纤维化程度。方法:18只SD大鼠随机分为正常对照组(NC组)、糖尿病... 详细信息

目的:探讨在糖尿病肾病(DKD)大鼠模型中,骨形态发生蛋白7(BMP7)是否通过下调Ajuba水平,降低Yes相关蛋白1(YAP1)的表达,进而减轻细胞外基质(ECM)沉积从而减轻DKD大鼠肾组织纤维化程度。方法:18只SD大鼠随机分为正常对照组(NC组)、糖尿病组(DM组)和DM+过表达BMP7腺相关病毒组(DM+rAAVBMP7组),每组6只。采用尾静脉注射55 mg/kg链脲佐菌素(STZ)建立DM大鼠模型。NRK-52E细胞分为正常糖组、高糖(HG)组和HG+rhBMP7组。HE和天狼星红染色观察大鼠肾皮质病理形态学变化;免疫组织化学染色检测肾皮质Ajuba、YAP1的表达部位;Western blot法检测大鼠肾皮质及NRK-52E细胞中BMP7、Ajuba和YAP1、Ⅲ型胶原(Col-Ⅲ)和纤维连接蛋白(fN)的蛋白表达水平;RT-qPCR检测大鼠肾皮质Ajuba和YAP1 mRNA的表达水平。结果:生化指标检测显示DM组大鼠血糖、血肌酐、甘油三酯、总胆固醇及24 h尿蛋白水平较NC组显著升高(Plot结果显示DM组或HG组中fN、Col-Ⅲ、Ajuba和YAP1的蛋白水平上调(P<0.05),但在DM+rAAV-BMP7组中上述蛋白表达水平又显著降低(P<0.05);RT-qPCR结果显示DM组Ajuba、YAP1的mRNA水平较NC组显著上升(P<0.05),DM+rAAV-BMP7组Ajuba、YAP1的mRNA水平较DM组又显著降低(P<0.05)。结论:过表达BMP7可减轻DKD大鼠的肾纤维化,其机制可能与下调Ajuba,减少YAP1的表达,从而抑制了ECM的沉积有关。

关键词：糖尿病肾病骨形态发生蛋白7 Ajuba Yes相关蛋白1 肾纤维化

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Precision bending of high-quality components for volume applications

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Transactions of Nonferrous Metals Society of China 2010年第11期20卷 2100-2110页

作者： T.WElO f.WIDERE Department of Engineering Design and Materials Norwegian University of Science and Technology(NTNU)

Recent new technology developments were presented in the field of industrial bending operations,including flexible stretch forming and 3D rotary stretch *** were made to give an overview of different mechanisms that influence dimensional accuracy,including local cross-sectional deformations such as suck-in and volume conservation effects,along with global deformations such as *** analytical model was developed to determine the particular influence of different material,geometry and process parameters on dimensional variability of bent *** results were discussed in terms of overall process capability(Cp) and associated process *** results show that different governing mechanisms prevail in various bending operations,meaning that attention has to be placed on controlling those process parameters that really are important to part quality in each specific *** strategies may be defined for reducing *** alternative may be to design more robust process and tool technology that reduce the effect of upstream parameters on dimensional variability of the formed *** results show that optimal tool design and technology may in specific cases improve the dimensional accuracy of a formed *** on the findings discussed herein,it is concluded that advances in industrial bending operations require focus on improving the understanding of mechanical mechanisms,including models and parameter development,new technology developments,including process,tool,measurement and control capabilities,and process discipline at the shop floor,combined with a basic philosophy of controlling process parameters rather than part attributes.

关键词：精密弯曲工艺参数控制应用元件品质尺寸精度拉伸成形回弹变形

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Seasonal variations of PM10 -- Trace elements, PAHs and levoglucosan: Rural sugarcane growing area versus coastal urban area in Southeastern florida, USA. Part II: Elemental concentrations

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Particuology 2019年第5期17卷 99-108页

作者： Orhan Sevim oglu Wolfgang f. Rogge Department of Environmental Engineering Cebze Technical University Cebze Kocaeli 41400 Turkey School of Engineering and Sierra Nevada Research Institute University of California Merced. 5200 North Lake Road Merced CA 95343 USA

The largest sugarcane-growing area in the United States is in South florida. An estimated 7 million tons of dry sugarcane leafy biomass is removed from the fields before harvest by burning the leaves off the sugarcane stalks. Preharvest sugarcane leaf foliage burning is a major source of airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), biogenic trace elements such as K, volatile hydrocarbons and other pollutants. In one harvesting period, approximately 22 million tons of C02, a greenhouse gas, is released, 7 million tons from leaf foliage preharvest burning alone and 15 million tons from burning sugarcane bagasse in the sugar mills for power generation. In this study, PMio was collected from Belle Glade, close to the sugarcane-growing area, and from Delray Beach, an urbanized area along the East Coast of florida. The PM samples were analyzed for trace elements and close to organic compounds. To elucidate the importance of preharvest sugarcane biomass smoke emissions on air quality, 39 trace elements, 18 PAHs, and levoglucosan were selected to apportion ambient PM constituents. Al, Ca and to a great extend also Mg are the major soil-related trace elements and key markers for fugitive soil dust emissions. Similarly, sea salt aerosol blown from the Atlantic Ocean into florida added appreciably to PMio trace elements concentration, especially Na and Cl. Approximately half of the sea salt aerosol (PMjo -portion) by mass is removed from the atmosphere during the transport of ocean air from Delray Beach to Belle Glade. Ambient acid displacement reactions caused a substantial portion of the Cl (30%) to be liberated from the sea salt aerosol to the atmosphere during transport as gaseous HC1. The PAH concentrations at Belle Glade were high when the biomass combustion markers levoglucosan and Ilso showed the highest concentrations. This indicates that during the sugarcane harvest season, when leaf foliage is burned off just before harvest, most of

关键词： Urban versus rural Trace elements Sugarcane burning Rare earth elements Sea salt aerosol Potassium levoglucosan PAHs

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Three-dimensional simulation of long-wavelength free-electron lasers with helical wiggler and ion-channel guiding

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Chinese Physics B 2013年第7期22卷 183-191页

作者： f. Jafari Bahman B. Maraghechi Department of Physics Amirkabir University of Technology

A three-dimensional simulation of a steady-state amplifier model of a long-wavelength free-electron laser （fEl） with realizable helical wiggler and ion-channel guiding is presented. The set of coupled nonlinear differential equations for electron orbits and fields of TE 11 mode in a cylindrical waveguide are solved numerically by the Runge–Kutta algorithm with averages calculated by the Gaussian quadrature technique. Self-fields and space-charge effects are neglected, and the electron beam is assumed to be cold and slippage is ignored. The parameters correspond to the Compton regime. Evolution of the radiation power and growth rate along the wiggler is studied. Ion-channel density is chosen to obtain optimum efficiency. Simulations are preformed for the fEl operating in the neighborhood of 35 GHz and 16.5 GHz for the electron beam energies of 250 keV and 400 keV, respectively. The result of the saturated efficiency was found to be in good agreement with the simple estimation based on the phase-trapping model.

关键词： free-electron laser helical wiggler ion-channel guiding

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An Alternative to free Entropy for free Group factors

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Acta Mathematica Sinica,English Series 2003年第3期19卷 419-472页

作者： MichalDOST/~l DonHADWIN Mexicka4 Praha10CZ-10100CzechRepublic DepartmentofMathematics UniversityofNewHampshireDurhamNH03824-3591USA

In this paper we define a very simple invariant η(V^-) for a k-tuple V^-of unitaries in a finite factor von Neumann algebra, and we show how this invariant can replace free entropy in many of the important applications. We also introduce a notion of metric free entropy and some related *** include proofs, using η, of the theorems of liming Ge and of D. Voiculescu, respectively, on the primeness of and on the absence of Cartan snbalgebras in the noncommutative free group factors.

关键词： free entropy Metric free entropy free group factor 46l54

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Discriminated Dimensional Analysis Versus Classical Dimensional Analysis and Applications to Heat Transfer and fluid Dynamics

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Chinese Journal of Chemical Engineering 2007年第5期15卷 626-631页

作者： f. Alhama C.N. Madrid Department of Applied Physics Technical University of Cartagena Campus Muralla del Mar Cartagena 30203 Spain

与古典维的分析相对照，区别了维的分析假设空间坐标是独立于对方的在尺寸上并且允许在维的基础要过去常的几何数量的另外的类型，例如表面和角度。作为后果，区别了维的分析导致维的组的一个更低的数字，它使答案更精确。而且，这些区... 详细信息

与古典维的分析相对照，区别了维的分析假设空间坐标是独立于对方的在尺寸上并且允许在维的基础要过去常的几何数量的另外的类型，例如表面和角度。作为后果，区别了维的分析导致维的组的一个更低的数字，它使答案更精确。而且，这些区别的组以力量和精力平衡有一个清楚的物理意思。纸介绍这种技术并且为主要数量和热转移和液体流动地的物理参数提供维的方程。二应用被介绍表明这个方法的效率。

关键词：因次分析方法传统方法传热力学流体力学

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