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3d flow Past Transonic Turbine Cascade SE 1050-Experiment and Numerical Simulations

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journal of Thermal Science 2013年第4期22卷 311-319页

作者： d.imurda j.fürst M.Luxa Institute of Thermomechanics AS CR v.v.i.Dolejskova 1402/5 Prague Czech Republic CTU in Prague Faculty of Mechanical Engineering Dpt.of Technical MathematicsKarlovo Náměstí 13 Prague Czech Republic

This paper is concerned with experimental and numerical research on 3d flow past prismatic turbine cascade SE1050 （known in QNET network as open test case SE1050）. The primary goal was to assess the influence of the inlet velocity profile on the flow structures in the interblade channel and on the flow field parameters at the cascade exit and to compare these findings to results of numerical simulations. Investigations of 3d flow past the cascade with non-uniform inlet velocity profile were carried out both experimentally and numerically at subsonic （M2 = 0.8） and at transonic （M2 = 1.2） regime at design angle of incidence. Experimental data was obtained using a traversing device with a five-hole conical probe. Numerically, the 3d flow was simulated by open source code OpenfOAM and in-house code. Analyses of experimental data and Cfd simulations have revealed the development of distinctive vortex structures resulting from non-uniform inlet velocity profile. Origin of these structures results in increased loss of kinetic energy and spanwise shift of kinetic energy loss coefficient distribution. differences found between the subsonic and the transonic case confirm earlier findings available in the literature. Results of Cfd and experiments agree reasonably well.

关键词： blade cascade vortex structures transonic flow Cfd

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水泥碳汇核算及其对中国碳中和的贡献

中国科学：地球科学 2024年第6期54卷 2086-2097页

作者：马铭婧黄子王娇月牛乐张文凤徐晓伟郗凤明刘竹中国科学院沈阳应用生态研究所沈阳110016 中国科学院大学北京100049 清华大学地球系统科学系北京100084 department of Engineering Science University of OxfordOxfordOX13UK

水泥是全球用量最高、用途最广的建筑材料之一,同时水泥生产也是人为活动碳排放的重要来源之一.水泥材料中的碱性化合物能缓慢吸收周围环境中的CO_(2)发生碳化反应,形成特殊的碳汇效应.中国是水泥生产与消费大国,科学系统核算中国水泥... 详细信息

水泥是全球用量最高、用途最广的建筑材料之一,同时水泥生产也是人为活动碳排放的重要来源之一.水泥材料中的碱性化合物能缓慢吸收周围环境中的CO_(2)发生碳化反应,形成特殊的碳汇效应.中国是水泥生产与消费大国,科学系统核算中国水泥碳汇量并明确其对碳中和的贡献值得深入探讨.通过构建水泥全生命周期碳汇核算综合分析模型,发现1930~2021年中国水泥碳汇量不断增长,到2021年高达426.77Mt CO_(2)(95%置信区间CI:317.67~874.33Mt CO_(2)),相当于中国年陆地碳汇的8.10%~45.40%,全球陆地碳汇的2.51%~4.54%,是全球碳循环中不可忽视的重要因素.在此期间,水泥的累积碳吸收量约为7.06Gt CO_(2)(95%CI:5.22~9.44Gt CO_(2)),抵消了同期水泥工业过程排放(13.91Gt CO_(2), 95%CI:12.44~17.00Gt CO_(2))的50.7%.其中,水泥砂浆对碳吸收贡献最大,占总量的65.64%.从生命周期的角度看,使用阶段的水泥材料碳吸收量占比最高(90.03%).水泥碳汇核算模型不仅提高了水泥行业碳核算的准确性,而且为中国乃至全球碳中和评估提供了科学依据.水泥材料及其废弃物的未来吸收潜力巨大,应进一步加强水泥材料的生态效益,加速水泥及其废弃物的CO_(2)封存技术研发和产业化进程,助力中国早日实现碳中和目标.

关键词：水泥碳汇生命周期评价碳减排碳中和

MICROSTRUCTURE ANALYSIS ANd MEchaNICAL PROPERTIES Of Zn-Al ALLOY ROd PROdUCEd BY HEATEd MOLd CONTINUOUS CASTING

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 241-248页

作者： Y.ma Y.Hao f.Y.Yan H.j.Liu State Key Laboratory of Advanced Nonferrous materials Lanzhou University of Science & Technology Lanzhou 730050 ChinaState Key Laboratory of Advanced Nonferrous Materials Lanzhou University of Science & Technology Lanzhou 730050 ChinaState Key Laboratory of Advanced Nonferrous Materials Lanzhou University of Science & Technology Lanzhou 730050 ChinaSchool of Mechano-Electronic EngineeringHua Qian University Quanzhou 362011China

The new technology of continuous casting by heated mold was used to produce directional solidification ZA alloy lines to eliminate the inter defects of these lines and increase their mechanical properties. The results are as follows: (1) The microstruc-ture of the ZA alloy lines is the parallel directional dendritic columnar crystal. Every dendritic crystal of eutectic alloy ZA5 was composed of many layer eutectic β and η phases. The micro structure of hypereutectic ZA alloys is primary dendritic crystal and interdendritic eutectic structure. The primary phase of ZA8 and ZA12 is β, among them, but the primary phase of ZA22 and ZA27 is a. (2) Through the test to the as-cast ZA alloy lines made in continuous casting by heated mold, it is found that the tensile strength and hardness increase greatly, but the elongation decreases. With the increase of aluminum amount from ZA 5 to ZA 12, ZA22 and ZA27, the tensile strength increases gradually. ZA27 has the best comprehensive mechanical properties in these four kinds of ZA alloys. (3) Heat treatment can decrease the dendritic segregation and improve the elongation of ZA alloy, but make their strength decrease slightly.

关键词： zinc-aluminum alloy heated mold continuous casting mechanical properties heat treatment

Investigation of Chemical Properties by NMR during the Laboratory Aging of Asphalt

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武汉理工大学学报 2010年第17期32卷 43-46页

作者： ma L X WU S P HUANG j f School of Transportation Wuhan University of TechnologyWuhan 430063China Key Laboratory of Silicate materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Communications Planning and design Institute of Hubei Province Wuhan 430051China

In this work,the chemical properties of asphalt were evaluated during the laboratory aging. The rolling thin film oven (RTfO),termed as short-term aging,and pressurized aging vessel (PAV),termed as long-term aging. Tests were used to simulate the laboratory aging of this asphalt. The performance characteristics of asphalt depends the chemical composition of asphalt. NMR spectroscopy enables etailed information about the Carbon-and-hydrogen types of asphalt without separating it into different components. Carbon and proton NMR measurements of asphalt showed that isomerization was the main chemical reactions of hydrocarbon groups following aging. The Corbett fractionation procedure was used to separate fresh and aged asphalts into four generic fractions,namely; asphaltenes,aromatics,resins and saturates were applied to evaluate the chemical changes that occurred during the aging processes.

关键词： asphalt ageing chemical characteristics NMR

Erratum to:Cadmium nanoclusters in a protein matrix:Synthesis,characterization,and application in targeted drug delivery and cellular imaging

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Nano Research 2024年第6期17卷 5755-5755页

作者： Morteza Sarparast Abolhassan Noori Hoda Ilkhani S.Zahra Bathaie maher f.El-Kady Lisa j.Wang Huong Pham Kristofer L.marsh Richard B.Kaner Mir f.Mousavi department of Chemistry Tarbiat Modares UniversityTehran 14115-175Iran department of Clinical Biochemistry Faculty of Medical SciencesTarbiat Modares UniversityTehran 14115-111Iran department of Chemistry and Biochemistry University of CaliforniaLos AngelesLos AngelesCA 90095USA department of Chemistry Faculty of ScienceCairo UniversityGiza 12613Egypt California NanoSystems Institute University of CaliforniaLos AngelesLos AngelesCA 90095USA

The Electronic Supplementary material available online erroneously only contains the first six pages of the entire supplementary material *** will find the entire supplementary material file online linked to this publisher’s *** publisher apologizes to the authors and readers for this *** Supplementary material:Supplementary material(detailed description on procedures,and further characterizations,including synthesis,optimization,and characterization of CdNCs,HA-CdNCs,and dOX-HA-CdNCs;calculating quantum yield;a jellium model for assigning the most valid number of the atoms in the NCs;drug loading and release;cellular uptake and cytotoxicity)is available in the online version of this article at https://***/10.1007/s12274-016-1201-z.

关键词： characterization matrix calculating

自主机器人使能技术在制造业中的应用（英文）

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期 403-431页

作者： ERd?S Gábor ABAI Kristóf BEREGI Richárd CSEMPESZ jános CSERTEG Tamás GOdó Gábor HAjóS Mátyás HáY Borbála HORVáTH dániel HORVáTH Gergely jUNIKI ádám KEMéNY Zsolt KOVáCS András NACSA jános PANITI Imre PEdONE Gianfranco TAKáCS Emma TIPARY Bence ZAHORáN László VáNCZA józsef 匈牙利研究网络计算机科学与控制研究所布达佩斯经济与技术大学制造科学与技术系 EPIC非盈利创新实验室厄特沃什·罗兰大学

自主制造系统的研究既受益于信息物理融合系统这一新技术的推动，也响应工业实际需求的号召。目前，先进的传感器技术、数字孪生、人工智能和新型通信技术可以支持半结构化工业环境中的自主操作，可实现对生产过程的实时监控、情况识别... 详细信息

自主制造系统的研究既受益于信息物理融合系统这一新技术的推动，也响应工业实际需求的号召。目前，先进的传感器技术、数字孪生、人工智能和新型通信技术可以支持半结构化工业环境中的自主操作，可实现对生产过程的实时监控、情况识别和预测、自动和自适应（重新）规划、团队合作，以及通过学习提高性能。本文总结了实现自主工业机器人技术的主要需求，提出了实现此类系统的通用工作流程，并介绍了HUN-REN SZTAKI最近在装配、焊接、打磨、拾取和放置以及机械加工等多个应用领域的广泛实践。这些解决方案的共同点是以通用的数字孪生概念为核心。最后，本文提出实现工业自主机器人解决方案的一般建议，并讨论了未来要研究的一些开放性问题。

关键词：工业机器人自动化数字孪生使能技术

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)

Evolution of heart transplant donor characteristics in the 21st century: A United States single center’s experience

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World journal of Transplantation 2024年第3期14卷 22-29页

作者： Alexander M Spring Christiana Gjelaj Shivank madan Snehal R Patel Omar Saeed Sandhya Murthy Yogita Rochlani daniel B Sims Sasha Vukelic Stephen j forest jamil f Borgi daniel j Goldstein Ulrich P jorde Montefiore-Einstein Center for Heart and Vascular Care Montefiore Medical CenterAlbert Einstein College of MedicineBronxNY 10467United States division of Cardiothoracic Surgery Tulane UniversityNew OrleansLA 70112United States

despite a record setting number of heart transplants performed annually,the national donor shortage continues to plague transplant teams across the United *** we describe the barriers to adaptation of numerous“non-traditional”orthotopic heart transplant donor characteristics including donors with hepatitis C virus,those meeting criteria for donation after cardiac death,donors with coronavirus disease 19 infection,donors with the human immunodeficiency virus,and grafts with left ventricular systolic *** center’s objective was to increase our transplant volume by expanding our donor pool from“traditional”donors to these“non-traditional”*** detail how medical advances such as certain laboratory studies,pharmacologic interventions,and organ care systems have allowed our center to expand the donor pool thereby increasing transplantation volume without adverse effects on outcomes.

关键词： Orthotopic heart transplantation Hepatitis C virus COVId-19 Left ventricular systolic dysfunction Human immunodeficiency virus donation after cardiac death

Recurrent gene flow between Neanderthals and modern humans over the past 200,000 years

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四川生理科学杂志 2024年第7期46卷 1621-1621页

作者： Liming Li Troy j. Comi Rob f. Bierman joshua M. Akey department of Medical Genetics and developmental Biology School of Medicine The Key Laboratory of Developmental Genes and Human Diseases Ministry of Education Southeast University Nanjing 210009 China. The Lewis-Sigler Institute for Integrative Genomics Princeton University Princeton NJ 08540 USA.

Although it is well known that the ancestors of modern humans and Neanderthals admixed,the effects of gene flow on the Neanderthal genome are not well *** develop methods to estimate the amount of human-introgressed s... 详细信息

关键词： flow modern apply