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Micro-scale Abrasion and Medium Load Multiple Scratch Tests of PVd Coatings

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材料热处理学报 2004年第05B期25卷 1199-1202页

作者： S. Poulat d.g Teer Teer Coatings Ltd Droitwich Worcestershire.U.K.Teer Coatings Ltd Droitwich Worcestershire.U.K.

Micro-scale abrasion testing is widely used to determine the abrasion resistance of thin film coatings; it is a simple technique that can easily be used as part of a quality control procedure, but it has got the disadvantage of not allowing an easy study of the wear mechanisms involved: it is difficult to estimate the load applied on each abrasive particles in the contact between the loaded ball and the specimen. The possibility of using progressive loading scratch testing, a method widely used to assess the adhesion of thin film coatings, to model the abrasive wear of coatings has been studied in the past; the use of multiple scratch tests to study the wear mechanisms corresponding to a single abrasion scratch event has also been studied in the case of bulk materials (ceramics and hard metals). Two coatings, deposited by Closed Field Unbalanced Magnetron Sputter Ion Plating (CFUBMSIP) on ASP23 powder metallurgy steel substrate are chosen to be representative of the use of protective coatings in industry: titanium nitride, which is widely used to prevent tool wear, and TCL graphit-iC?, which is widely used as a wear resistant solid lubricant coating. The two coatings are first characterised by using a standard quality control procedure: their thickness is determined by the cap grinding method, their adhesion by progressive loading scratch. Then micro-scale abrasion tests performed with a slurry at a concentration which promotes grooving wear, and medium load multiple scratch tests performed with diamond indenters are completed; the results of these tests are analysed and compared to determine if there is any correlation between the two sets of results; the multiple scratch tests wear tracks are also observed to determine the wear mechanisms involved.

关键词：微量磨损乱痕硬度试验 PVd 薄膜涂层

Fabrication and characterization of rugate structures composed of SiO_(2) and Nb_(2)O_(5)

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光学精密工程 2005年第4期13卷 505-511页

作者： R.Leitel O.Stenzel S.Wilbrandt d.gäbler V.Janicki N.Kaiser Institut für Angewandte Physik Friedrich Schiller University JenaMax-Wien-Platz 107743 JenaGermany Optical Coatings department Fraunhofer Institut für Angewandte Optik und FeinmechanikAlbert-Einstein-Str.7D-07745 JenaGermany Institute Ruder Boskovic Bijenicka 5410000 ZagrebCroatia

gradient index layers and rugate structures were fabricated on a Leybold Syrus pro deposition system by plasma-assisted coevaporation of the low index material silica and the high index material niobium *** obtain information about the compositional profiles of the produced layers,cross sectional transmission electron microscopy was used in assistance to deposition rate data recorded by two independent crystal monitors during the film *** depth dependent concentration profiles were transformed to refractive index gradients by means of effective medium *** on the refractive index gradients the corresponding samples`transmission and reflection spectra could be calculated by utilizing matrix *** relevance of the established refractive index profiles could be verified by comparison of the calculated spectra with the measured ones.

关键词： physical vapor deposition effective medium approximation rugate structure

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非平衡晶化控制水滑石晶粒尺寸

无机化学学报 2001年第6期17卷 830-834页

作者：赵芸矫庆泽李峰 Evans d.g 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

本文采用非平衡晶化法通过在晶化后期补加原料合成了一系列不同晶粒尺寸的水滑石LdH样品研究表明非平衡晶化法可在一定范围内调控LdH的粒径所合成的LdH样品组成稳定晶体结构完整。

关键词：镁铝水滑石晶粒尺寸非平衡晶化尺寸控制双金属复合氧化剂催化剂

In-vitro assessment for the control of Fusarium species using a lactic acid bacterium isolated from yellow pitahaya(Selenicereus megalanthus(K. Schum. Ex Vaupel Moran))

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Journal of Integrative Agriculture 2021年第1期20卷 159-167页

作者： Leidy J.VALENCIA-HERNANdEZ Karina LÓOPEZ-LÓPEZ Eyder d.gÓMEZ-LÓPEZ Liliana SERNACOCK Cristobal N.AgUILAR Universidad Nacional de Colombia Palmira CampusValle 763533Colombia Food Research department School of ChemistryAutonomous University of CoahuilaSaltillo CampusCoahuila 25280Mexico

The fungistatic activity of a lactic acid bacterium, which had been isolated from yellow pitahaya cultures, against fungi associated with basal rot(Fusarium oxysporum and Fusarium fujikuroi) was measured in the present study. Its activity was assessed in three fractions: fermented(S1), metabolic products(S2), and biomass(S3), using two fermentation substrates: Man Rogosa Sharpe agar(MRS) and potato dextrose agar(PdA). The bacterium was molecularly identified as Lactobacillus plantarum. S3 reduced F. fujikuroi growth by 100% over 48 h of fermentation, which occurred during the stationary phase of bacterial growth. The three fractions' fungistatic activity against F. fujikuroi depended on the substrate employed. The fermentation kinetic parameters for L. plantarum indicated that its specific growth rate was 0.46 h^–1, with 93.63% substrate consumption, 0.045 kg kg^–1 cell yield, and 0.54 kg kg^–1 product yield. The kinetic parameters calculated will allow for bacteria production scaling. These in-vitro trials reveal L. plantarum's possible application as a biocontrol agent for diseases associated with Fusarium. However, further ex-vivo and in-vivo researches are required to demonstrate its behavior in crops.

关键词： lactic acid bacteria Fusarium fungistatic activity biomass yellow pitahaya

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硼酸根插层水滑石层间组成及取向结构的控制

化学学报 2004年第13期62卷 1205-1210,J001页

作者：李素锋李殿卿史翎杨兰蒲敏 Evans d.g 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

以Mg0 .67Al0 .3 3 (OH) 2 (CO3 ) 0 .165·0 .62H2 OLdHs为前体 ,以水为分散介质 ,由离子交换法组装了硼酸根插层LdHs ,并用XRd ,FT IR ,Tg dTA ,ICP ,11BMASNMR等手段对样品进行了分析和表征 .结果表明 ,通过控制离子交换时的pH ,可... 详细信息

以Mg0 .67Al0 .3 3 (OH) 2 (CO3 ) 0 .165·0 .62H2 OLdHs为前体 ,以水为分散介质 ,由离子交换法组装了硼酸根插层LdHs ,并用XRd ,FT IR ,Tg dTA ,ICP ,11BMASNMR等手段对样品进行了分析和表征 .结果表明 ,通过控制离子交换时的pH ,可使硼酸根取代Mg Al CO3 LdHs前体层间的CO2 -3 ,且可控制离子交换程度及客体的取向 ,从而控制插层结构 .对硼酸根插层LdHs的结构进行研究发现 ,控制pH =4.5 ,层间阴离子主要是一硼酸根和离子平面与LdHs层板平行的三硼酸根 ,出于结构稳定的需要 ,CO2 -3 不能完全被置换 ;控制pH =3 .5 。

关键词：硼酸根插层水滑石层间组成取向结构离子交换硼酸 pH值阻燃剂

由Mg-Fe(Ⅱ)-Fe(Ⅲ) LdH层状前体制备MgFe_2O_4尖晶石的研究

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化学学报 2003年第1期61卷 51-57页

作者：刘俊杰李峰 EVANS d.g 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

提出了一种由层状前体合成单一晶相镁铁尖晶石的新方法,首先对Mg Fe(Ⅱ) Fe(Ⅲ)水滑石的制备进行了系统研究,成功合成了Mg2 +/Fe2 +/Fe3+摩尔比分别为 1/2/1,4/5/3,2/1/1的系列水滑石层状前体,结果表明在以上三种投料比下均可制备出晶... 详细信息

提出了一种由层状前体合成单一晶相镁铁尖晶石的新方法,首先对Mg Fe(Ⅱ) Fe(Ⅲ)水滑石的制备进行了系统研究,成功合成了Mg2 +/Fe2 +/Fe3+摩尔比分别为 1/2/1,4/5/3,2/1/1的系列水滑石层状前体,结果表明在以上三种投料比下均可制备出晶型较好的水滑石层状前体,并探讨了合成条件对晶体结构的影响规律.在此基础上,利用X射线衍射、振动样品磁强计和穆斯堡尔谱等手段研究了层状前体焙烧产物的结构、组成、磁性及微观信息,研究表明当Mg2 +/Fe2 +/Fe3+投料摩尔比为 2/1/1时。

关键词： MgFe2O4尖晶石镁铁铁水滑石共沉淀磁性铁氧体软磁材料

Candidate Eclipsing Binary Systems with aδScuti Star in Northern TESS Field

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Research in Astronomy and Astrophysics 2022年第8期22卷 34-48页

作者： F.Kahraman Aliçavuş d.gümüş Ö.Kırmızıtaş Ö.Ekinci S.Çavuş Y.T.Kaya F.Aliçavuş Çanakkale Onsekiz Mart University Faculty of Sciences and ArtsPhysics Department17100ÇanakkaleTurkey Çanakkale Onsekiz Mart University Astrophysics Research Center and Ulupnar ObservatoryTR-17100ÇanakkaleTurkey Istanbul University Institute of Graduate Studies in ScienceProgramme of Astronomy and Space Sciences34116BeyazıtIstanbulTurkey Çanakkale Onsekiz Mart University School of Graduate StudiesDepartment of PhysicsTR-17100ÇanakkaleTurkey Çanakkale Onsekiz Mart University School of Graduate StudiesDepartment of Space Sciences and TechnologiesTR-17100ÇanakkaleTurkey Çanakkale Onsekiz Mart University Faculty of Engineering Computer EngineeringTR-17100ÇanakkaleTurkey

The existence of pulsating stars in eclipsing binaries has been known for *** types of objects are extremely valuable systems for astronomical studies as they exhibit both eclipse and pulsation *** 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 *** are different types of pulsating stars existing in eclipsing *** of them is theδScuti ***,the known number ofδScuti stars in eclipsing binaries is around 90 according to the latest catalog of these *** increasing number of these kinds of variables is important to understand the stellar structure,evolution and the effect of binarity on the ***,in this study,we focus on discovering new eclipsing binaries withδScuti 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 T_(eff) values of the *** a result of these criteria,we discovered some *** orbital variations were first removed from the TESS light curves and frequency analysis was performed on the *** luminosity,and absolute and bolometric magnitudes of the targets were calculated as *** 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 *** addition,the positions of the systems in the H-R diagram were examined considering the flux density *** a consequence of the investigation,we defined 38 candidateδScuti stars and also one Maia variable in eclipsing binary systems.

关键词： (stars:)binaries:eclipsing stars:variables:delta Scuti techniques:photometric

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介孔镁铝复合氧化物的成孔机理及其结构特征

中国科学（B辑） 2002年第1期32卷 67-73页

作者：赵芸矫庆泽 d.g Evans 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

采用自行创制的成核/晶化隔离法,通过调变晶化时间制备了不同粒径的层状前体——镁铝水滑石,并将其于500℃焙烧,制得了孔径分布窄、具有介孔结构特征的镁铝复合氧化物,且该双金属复合氧化物的晶相结构是兼有MgO晶相和层状结构的复相结构.

关键词：镁铝水滑石镁铝复合氧化物介孔结构晶相结构成孔机理成核/晶化隔离法介孔材料

Cu-Ni-Mg-Al-CO_3四元水滑石的合成及结构分析

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化学学报 2003年第1期61卷 78-83页

作者：冯拥军李殿卿李春喜王子镐 EVANS d.g 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029 北京化工大学化学工程学院北京100029

以Cu(NO3)2 ·3H2 O,Ni(NO3)2 ·6H2 O,Mg(NO3)2 ·6H2 O和Al(NO3)3·9H2 O为原料,以NaOH和Na2 CO3为沉淀剂,采用成核/晶化隔离法合成了Cu Ni Mg Al CO3四元水滑石,通过XRd,FT IR,Tg dTA,ICP等手段对样品进行测试和表征,并且对水滑石结... 详细信息

以Cu(NO3)2 ·3H2 O,Ni(NO3)2 ·6H2 O,Mg(NO3)2 ·6H2 O和Al(NO3)3·9H2 O为原料,以NaOH和Na2 CO3为沉淀剂,采用成核/晶化隔离法合成了Cu Ni Mg Al CO3四元水滑石,通过XRd,FT IR,Tg dTA,ICP等手段对样品进行测试和表征,并且对水滑石结构的层板和层间阴离子相互作用进行分析和讨论.结果表明,控制Cu2 +离子与其它二价金属离子的配比,可制备晶体结构规整的M(II)4 M(III)2 (OH)12 CO3·4H2 O型水滑石;Cu2 +离子的引入导致了明显的Jahn Teller效应;且随Mg2 +量的增加,使得这种效应更加显著,另一方面Mg2 +量的增加有利于Cu Ni Mg Al CO3四元水滑石晶体在a方向上生长。

关键词： Cu-Ni-Mg-Al-CO3四元水滑石铜镍合成结构分析 Jahn-Teller效应催化剂前驱体镁铝