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Application of EBSD technique to ultrafine grained and nanostructured materials processed by severe plastic deformation:Sample preparation, parameters optimization and analysis

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Transactions of Nonferrous Metals Society of China 2012年第8期22卷 1801-1809页

作者：陈勇军 jarle HjELEN hans j.ROVEN 挪威科技大学材料科学与工程系特隆赫姆7491挪威

With the help of FESEM, high resolution electron backscatter diffraction can investigate the grains/subgrains as small as a few tens of nanometers with a good angular resolution （~0.5°）. Fast development of EBSD speed （up to 1100 patterns per second） contributes that the number of published articles related to EBSD has been increasing sharply year by year. This paper reviews the sample preparation, parameters optimization and analysis of EBSD technique, emphasizing on the investigation of ultrafine grained and nanostructured materials processed by severe plastic deformation （SPD）. Detailed and practical parameters of the electropolishing, silica polishing and ion milling have been summarized. It is shown that ion milling is a real universal and promising polishing method for EBSD preparation of almost all materials. There exists a maximum value of indexed points as a function of step size. The optimum step size depends on the magnification and the board resolution/electronic step size. Grains/subgrains and texture, and grain boundary structure are readily obtained by EBSD. Strain and stored energy may be analyzed by EBSD.

关键词： electron backscatter diffraction (EBSD) sample preparation parameters optimization step size severe plastic deformation (SPD)

Portal vein thrombosis and arterioportal shunts:Effects on tumor response after chemoembolization of hepatocellular carcinoma

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World journal of Gastroenterology 2011年第10期17卷 1267-1275页

作者： Thomas j Vogl Nour-Eldin Nour-Eldin Sally Emad-Eldin Nagy NN Naguib joerg Trojan hans Ackermann Omar Abdelaziz Institute for Diagnostic and Interventional Radiology Johan Wolfgang Goethe University Hospital Diagnostic and Interventional Radiology Department Cairo University Hospital

AIM: To evaluate the effect of portal vein thrombosis and arterioportal shunts on local tumor response in advanced cases of unresectable hepatocellular carcinoma treated by transarterial chemoembolization. METHODS: A retrospective study included 39 patients (mean age: 66.4 years, range: 45-79 years, SD: 7) with unresectable hepatocellular carcinoma (HCC) who were treated with repetitive transarterial chemoembolization (TACE) in the period between March 2006 and October 2009. The effect of portal vein thrombosis (PVT) (in 19 out of 39 patients), the presence of arterioportal shunt (APS) (in 7 out of 39), the underlying liver pathology,Child-Pugh score, initial tumor volume, number of tumors and tumor margin definition on imaging were correlated with the local tumor response after TACE. The initial and end therapy local tumor responses were evaluated according to the response evaluation criteria in solid tumors (RECIST) and magnetic resonance imaging volumetric measurements. RESULTS: The treatment protocols were well tolerated by all patients with no major complications. Local tumor response for all patients according to RECIST criteria were partial response in one patient (2.6%), stable disease in 34 patients (87.1%), and progressive disease in 4 patients (10.2%). The MR volumetric measurements showed that the PVT, APS, underlying liver pathology and tumor margin definition were statistically significant prognostic factors for the local tumor response (P = 0.018, P = 0.008, P = 0.034 and P = 0.001, respectively). The overall 6-, 12- and 18-mo survival rates from the initial TACE were 79.5%, 37.5% and 21%, respectively. CONCLUSION: TACE may be exploited safely for palliative tumor control in patients with advanced unresectable HCC; however, tumor response is significantly affected by the presence or absence of PVT and APS.

关键词： Hepatocellular carcinoma Transarterialchemoembolization Portal Shunt Thrombosis

DSC analyses of static and dynamic precipitation of an Al–Mg–Si–Cu aluminum alloy

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Progress in Natural Science:Materials International 2015年第2期25卷 153-158页

作者： Manping Liu Zhenjie Wu Rui Yang jiangtao Wei Yingda Yu P?l C. Skaret hans j. Roven School of Materials Science and Engineering Jiangsu Province Key Laboratory of Materials Tribology Jiangsu University Department of Materials Science and Engineering Norwegian University of Science and Technology (NTNU)

In the present investigation, both static and dynamic precipitations of an Al–Mg–Si–Cu aluminum alloy after solid-solution treatment(SST)were comparatively analyzed using differential scanning calorimetry(DSC). Dynamic aging was performed in the SST alloy through equal channel angular pressing(ECAP) at different temperatures of room temperature, 110, 170, 191 and 300 1C. For comparison, static artificial aging was conducted in the SST alloy at 191 1C with two aging times of 4 and 10 h. The DSC analyses reveal that the dynamic precipitation has occurred in the ECAPed samples, while the activation energies associated with the strengthening precipitates in the dynamic samples are considerably higher than the energies in the SST and static aged samples. The higher activation energies are probably attributed to the smaller grains and higher dislocation density developed after ECAP. The results in the present investigation allow the prediction of the type of the dynamic precipitates to influence the strength of the ultrafine grained alloy during ECAP at various temperatures.

关键词： Differential scanning calorimetry Al–Mg–Si–Cu aluminum alloy Dynamic aging Precipitation behaviors Equal channel angular pressing Severe plastic deformation

Prevalence of refractive errors in Hungary reveals three-fold increase in myopia

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International journal of Ophthalmology(English edition) 2022年第7期15卷 1174-1179页

作者： jános Németh TennóDaiki Gergely Dankovics István Barna hans Limburg Zoltán Zsolt Nagy Department of Ophthalmology Semmelweis UniversityBudapest 1085Hungary Comprehensive Health Test Program of Hungary Szentendre 2000Hungary Department of Media and Education Informatics Eötvös Loránd UniversityBudapest 1053Hungary 1st Department of Internal Medicine Semmelweis UniversityBudapest 1083Hungary Health Information Services Grootebroek 1613LCThe Netherlands

AIM:To examine the prevalence and composition of refractive errors in ***:Nationwide cross-sectional data collected between 2014 and 2019 were analysed from the Comprehensive Health Screening Program of Hungary,which provided spectacle dioptric power and autorefractometry data for 68227 people(35850 women and 32377 men).Their age distribution,18-99y,was similar to the national demographic ***:Of the total population,16.50%of the refractive errors exhibited hyperopia,40.05%emmetropia,and 43.45%*** was 3 times more frequent(58.7%)in younger ages(18-35y of age)compared to older age groups(19.4%of those 56-70y of age;P<0.001).High myopia showed a low prevalence(0.21%),and an increase parallel with ageing(r=0.716;P=0.009).CONCLUSION:Myopia is the most frequent refractive error in *** prevalence of myopia is especially increased,up to 2-3 times,in the younger age *** actions need to be taken to reduce the onset of myopia and its associated consequences.

关键词： refractive errors myopia hyperopia emmetropia Hungary

Problem Solving Solutions in Thermal Spray:HSE and Overspray

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有色金属（冶炼部分） 2008年第S1期 139-145页

作者： hans Keller joachim Beczkowiak Stefan Zimmermann Benno Gries jürgen Fischer H.C.Starck GmbH LaufenburgDeutschland H.C.Starck GmbH GoslarDeutschland

目前金属基材料的原材料成本对热喷涂涂层的经济性造成压力。特别是材料挥发和近期铼、钨、钴和镍基材料的价格增长,对各应用领域的许多涂层的经济性造成严重威胁。由于沉积效率的限制,喷涂中未沉积物问题变得越来越重要,不仅只是减少浪... 详细信息

目前金属基材料的原材料成本对热喷涂涂层的经济性造成压力。特别是材料挥发和近期铼、钨、钴和镍基材料的价格增长,对各应用领域的许多涂层的经济性造成严重威胁。由于沉积效率的限制,喷涂中未沉积物问题变得越来越重要,不仅只是减少浪费,还可以从材料自身价值角度去看。回收是解决这个问题的一个措施,特别是当废料中含有高价值金属时。欧洲执行的REACH(化学制品的注册、评估、授权)将会逐步强制淘汰标有有毒的材料和物质的使用。在热喷涂中使用这些有毒物质或使用热喷涂产品可能暂时是安全的,然而,从法律限制和从其他工业领域得到的指示表明,像WC-Co粉末这样的化学制品对人体有害。要想在将来的涂层工厂中保持竞争性,必须符合不断提高的更严格的环保和安全规程。

关键词：热喷涂粉末 WC-Co 健康和环保毒物学回收喷涂中未沉积物

Economics and Performance of 10 Gb/s Metro Transport Over Mixed Fiber Plant of G.655 NZDF and G.652.C Zero Water-Peak Fibers

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光学学报 2003年第S1期23卷 717-718页

作者： hans-jrg Thiele Santanu Das Raymond Boncek Lynn E. Nelson OFS 791 Holmdel-Keyport Road Holmdel NJ 07733OFS 19 Schoolhouse Road Somerset NJOFS 2000 Northeast Expressway Norcross GAOFS 791 Holmdel-Keyport Road Holmdel NJ 07733

Using lower-cost lasers, 30% savings are possible for 10-Gb/s uncompensated metro transmission over NZDF, compared to G.652 fiber. We present WDM transmission results for a mixed plant of NZDF rings interconnected to ... 详细信息

关键词： of or on as Economics and Performance of 10 Gb/s Metro Transport Over Mixed Fiber Plant of G.655 NZDF and G.652.C Zero Water-Peak Fibers dBm DML EML WDM

Persistent elevation of fibrosis biomarker cartilage oligomeric matrix protein following hepatitis C virus eradication

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World journal of Hepatology 2019年第3期11卷 330-334页

作者： Kristofer ANDréasson G?ran j?nsson Roger HesselstrAND hans Norrgren Section of Rheumatology Department of Clinical Sciences Lund Lund University Section of Infectious Diseases Department of Clinical Sciences Lund Lund University

Serum levels of cartilage oligomeric matrix protein(COMP) has been presented as a biomarker of liver fibrosis in several cross-sectional studies. COMP is also an essential mediator in carcinoma development and has also been associated with hepatocellular carcinoma. We present a prospective analysis of this biomarker in38 patients with chronic hepatitis C who were subject to eradication therapy with direct acting antivirals. We confirm previous studies associating COMP elevation with liver cirrhosis. We also show how viral levels are correlated with COMP at baseline. In our prospective analysis, we report that successful eradication of hepatitis C results in improvement in liver stiffness and laboratory liver function tests at 1 year follow-up. In contrast, median COMP-levels remain unchanged during the study period. We conclude that the biomarker potential of COMP in the prospective evaluation of liver diseases, remains to be elucidated.

关键词： Hepatitis C Chronic Cartilage oligomeric matrix protein Fibrosis

鄂尔多斯盆地志留-泥盆纪和侏罗纪热事件——伊利石K-Ar年龄证据

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地质学报 1996年第2期70卷 186-194页

作者：赵孟为 hans Ahrendt Klaus Wemmer hans-jürgen Behr 格丁根大学地质与岩石圈动力学研究所

利用伊利石K-Ar测年法,结合伊利石结晶度分析,首次在鄂尔多斯盆地确定出两期不同时代热事件。晚三叠世和晚二叠世<0.2μm粒级的岩石样品的K-Ar年龄(159-173Ma)反映了与燕山运动有关的伊利石化年龄,指示有一期中侏罗世的热事件;其<2μm... 详细信息

利用伊利石K-Ar测年法,结合伊利石结晶度分析,首次在鄂尔多斯盆地确定出两期不同时代热事件。晚三叠世和晚二叠世<0.2μm粒级的岩石样品的K-Ar年龄(159-173Ma)反映了与燕山运动有关的伊利石化年龄,指示有一期中侏罗世的热事件;其<2μm粒级的K-Ar年龄(210-308Ma)则被解释为碎屑物和自生伊利石的混合年龄。中寒武世<0.2μm和<2μm粒级的岩石样品K-Ar年龄(368Ma与419Ma)对应于北秦岭加里东褶皱带变质作用与最早期花岗岩侵入的时代(380-420Ma),表明在志留-泥盆纪发生了一期热事件。

关键词：伊利石 K-Ar测年法志留纪热事件鄂尔多斯盆地

Large-eddy simulation of wind-blown sand under unstable atmospheric boundary layer

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Science Bulletin 2022年第14期67卷 1421-1424,M0003页

作者： Panli He jie Zhang hans j.Herrmann Ning Huang Key Laboratory of Mechanics on Disaster and Environment in Western China Lanzhou UniversityLanzhou 730000China College of Civil Engineering and Mechanics Lanzhou UniversityLanzhou 730000China Department 403 Rocket Force University of EngineeringXi’an 710025China Laboratoire de Physique et Mécanique des Milieux Hétérogènes École Supérieure de Physique et de Chimie Industrielles de la Ville de ParisParis 75005France Departamento de Física Universidade do CearáFortaleza 60020-181Brazil

Atmospheric turbulence which induced by wind shear and/or convection is non-uniform anisotropic flows of high Reynolds and Rayleigh number[1].According to the mechanism of turbulence generation,atmospheric boundary-layer stratification can be classified into neutral,unstable(convective)and stable[2].Observations show that sandstorms and wind-blown sand mostly occur under unstable stratifications from afternoon to early evening[3].As the surface absorbs the solar radiation,the surface temperature increases and vertical convection develops,which enhances the momentum exchange between the upper and lower layers and hence increases the near surface wind speed and shear stress[4].

关键词：大涡模拟剪切应力风沙运动风沙流大气边界层输沙率线性关系对流速度