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Effects of Sn addition on the microstructure and mechanical properties of extruded Mg-Bi binary alloy

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Journal of Magnesium and Alloys 2022年第3期10卷 920-931页

作者： Sang-Cheol Jin Jong un Lee Jongbin Go Hui Yu Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566South Korea Department of Materials Science and Engineering Kyoto UniversityYoshida-honmachiSakyo-kuKyoto606-8501Japan School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China

We investigated the effects of Sn addition on the microstructural characteristics and mechanical properties of an extruded Mg-Bi binary alloy by comparing Mg-5 Bi(B5)and Mg-5 Bi-4 Sn(BT54).Both the extruded alloys exhibit a partially recrystallized grain structure with a strong extrusion fiber texture and numerous Mg3Bi2 ***,the addition of Sn significantly decreases the average grain size of the extruded alloy from 123.9 to 75.2μ*** Sn solute atoms inhibit the activity of dislocation slip,which reduces the internal strain energy accumulated in the dynamically recrystallized(DRXed)grains during ***,this reduced strain energy leads to the decrease in the DRXed grain size owing to weakened grain growth during natural *** extruded BT54 alloy exhibits higher tensile strength and ductility than the extruded B5 *** improvement in the strength by the Sn addition is attributed to the combined effects of grain refinement,Sn solute atoms,and increased dislocation *** formation of{10-11}and{10-11}-{10-12}twins during tension is suppressed by the grain refinement,thereby improving the tensile elongation considerably.

关键词： Mg±Bi alloy Extrusion Dynamic recrystallization Microstructure Mechanical properties.

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低氮改造后次高压锅炉炉管失效分析

中国特种设备安全 2024年第7期40卷 44-48页

作者：张鑫陈志刚孙春生天津市特种设备监督检验技术研究院天津300192

随着国家对大气污染综合治理的力度越来越大,天津市内的锅炉基本完成低氮改造。目前低氮改造的方式有分级燃烧、预混燃烧和燃气再循环燃烧等。在对某台经过低氮改造的燃气次高压锅炉进行内部检验时,发现其炉管上部普遍存在氧化皮,通过... 详细信息

随着国家对大气污染综合治理的力度越来越大,天津市内的锅炉基本完成低氮改造。目前低氮改造的方式有分级燃烧、预混燃烧和燃气再循环燃烧等。在对某台经过低氮改造的燃气次高压锅炉进行内部检验时,发现其炉管上部普遍存在氧化皮,通过金相检测、硬度检测和壁厚检测等方法对炉管进行检测,并且进行失效分析,提出相应的改进措施。

关键词：次高压锅炉炉管低氮改造表面燃烧

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Nonylphenol in bivalves and sediments in the northeast coast of China

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Journal of Environmental Sciences 2010年第11期22卷 1735-1740页

作者： Juan Wang Won-joon shim un-hynk Yim Narayanan Kannan Donghao Li Key Laboratory of Nature Resources of Changbai Mountain and Functional Molecular Ministry of Education of China Yanbian University Yanji 133002 China. Oil and POPs Research Group Korea Ocean Research and Development Institute Geoje-shi 656-834 Korea

To understand nonylphenol （NP） contamination in the northeast coastal environment in China, NP was determined in 19 sediment and 20 bivalve samples collected during November 2005. NP was identified in all sediment samples in the range of 8.8 to 1.0 × 10^3 ng/g dw （dry weight）, with an average of 0.12 × 10^3 ng/g dw. Most of the bivalve samples （oysters and mussels） contained detectable amounts of NP that ranged from ND （not detected） to 7.6 × 10^3 ng/g dw, with an average value of 0.79 × 10^3 ng/g dw. These results indicated that NP is ubiquitous in sediments and bivalves from the northeast coast of China, and are even present in bivalves sold as seafood. Serious contamination with NP was recorded off the coast of Bohai Strait and in semi-enclosed coastal environment such as Jiaozhou Bay and Liaodong Bay. Possible environmental and human health implications were understood in this study.

关键词： nonylphenol Yellow Sea Bohai Sea sediment bivalve

Transmural dispersion of repolarization：a complementary index for cardiac inhomogeneity

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Journal of Geriatric Cardiology 2016年第1期13卷 99-100页

作者： Mehmet Dogan Omer Yiginer Gokhan Degirmencioglu Haluk un Ankara Mevki Military Hospital Department of Cardiology Ankara Turkey Gulhane Military Medical Academy Haydarpasa Training Hospital Department of Cardiology Istanbul Turkey

We read the article written by Nuis, et al. The authors investigated the effects of transcatheter aortic valve implantation （TAVI） on corrected QT dispersion （cQTD） in severe aortic stenosis patients. They concluded that, 40% of patients had defective cQTD recovery at six months after the procedure and this was associated with increased late mortality risk. We would like to contribute to the study from a different methodological perspective.

关键词： QT dispersion Repolarization Transcatheter aortic valve implantation

Gastric heterotopia of colon found cancer workup in liver abscess:A case report

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World Journal of Clinical Cases 2022年第15期10卷 5012-5017页

作者： Jun Gi Park Jeong Ill Suh Yeo un Kim Department of Internal Medicine College of MedicineDongguk UniversityGyeongju 38067South Korea

BACKGROunD Recently reported cases of pyogenic liver abscess associated with colonic cancer in the absence of underlying disease,have included a small number of cases of gastric heterotopia(GHT).GHT is a congenital anomaly composed of ectopic gastric mucosa and can occur anywhere in the gastrointestinal tract but is more frequently encountered in the cervical ***,it is rarely observed in ***,most reported cases of GHT of the colon involved the rectum,and GHT involving the colon proximal to the rectum is *** SUMMARY An 83-year-old male patient presented with fever and a diagnosis of pyogenic liver *** was performed for colon cancer workup and revealed a 1.0 cm sized polyp at the transverse *** polyp was removed by endoscopic mucosal resection by monopolar electrocauterization using a *** examination revealed *** administering intravenous antibiotics,the patient recovered *** GHT in the colon could affect the development of pyogenic liver abscess by enabling hematogenous propagation of Klebsiella pneumoniae through mucosal ***,more study is needed due to the lack of cases.

关键词： Gastric heterotopia Colon Liver abscess Case report

Upconversion optical nanomaterials applied for photocatalysis and photovoltaics:Recent advances and perspectives

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Frontiers of Materials Science 2019年第4期13卷 335-341页

作者： Timur sh.ATABAEV Anara MOLKENOVA Department of Chemistry School of Science and TechnologyNazarbayev UniversityNur-Sultan 010000Kazakhstan

Upconversion(UC)lanthanide nanomaterials have attracted enormous attention in the last two decades thanks to their unique ability to convert low-energy infrared photons into high-energy *** this mini-review,we briefly discussed the recent achievements related to the direct utilization of UC optical nanomaterials for photocatalysis and photovoltaic *** particular,selected examples of UCcontaining devices/nanocomposites with improved performance were *** addition,we outlined some challenges and future trends associated with the widespread usage of UC nanomaterials.

关键词： upconversion process nanoparticle luminescence photocatalysis photovoltaics

REFLEXIVITY OF POWERS OF THE MULTIPLICATION OPERATOR ON SPECIAL FunCTION SPACES

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Acta Mathematica Scientia 2012年第6期32卷 2279-2284页

作者： B. Yousefi sh. Khoshdel Department of Mathematics Payame Noor UniversityP.O.Box 19395-3697TehranIran

In this paper we present sufficient conditions for reflexivity of any powers of the multiplication operator acting on Banach spaces of formal Laurent series.

关键词： reflexive operator Banaeh space of Laurent series associated with a sequenceβ bounded point evaluation

Dry Sliding Oxidative Wear in Plain Carbon Dual Phase Steel

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Journal of Iron and Steel Research International 2007年第4期14卷 43-48页

作者： V Abouei H Saghafian sh Kheirandish Department of Metallurgy and Materials Engineering Iran University of Science and TechnologyNarmak 16844TehranIran

To investigate the tribological potential of the dual phase （DP） steel as a wear resistant material, the wear and the friction characteristics of this steel, which consists of hard martensite islands embedded in a ductile ferrite matrix, have been investigated and compared with those observed in plain carbon hardened （H） steel that has the same carbon content of 0.2%. Dry sliding wear tests have been carried out using a pin-on-disk wear testing machine at different normal loads of 21.3 N, 28. 5 N, 35.7 N, and 42.6 N and at a constant sliding velocity of 1.20 m/s. The analysis of surface and wear debris of samples showed that the wear mechanism was mainly mild oxidative. The friction and the wear rate of the H steel and the DP Steel have been explained with respect to the microstructure and the wear mechanism.

关键词： dual phase steel wear microstructure heat treatment

Optimum Environmental Load Design Criterion for Marine Structures Based on Investment and Benefit Analysis

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China Ocean Engineering 1998年第2期13卷 235-242页

作者： Zhang, sh Yu, YF Li, BX Ocean univ Qingdao Qingdao 266003 Peoples R China

Marine structures operating in natural ocean environment are subjected to various stochastic loads. For design of the marine structures, the most important task is to determine environmental load design criterion. This paper presents a method to determine the optimum environmental load design criterion for marine structures. This method is based on the investment and benefit analysis and it can reach the design purpose of decreasing total costs during the service life of the structures and increasing economic benefits.

关键词： marine structures investment-benefit analysis optimum environmental load design criterion