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Hot Corrosion Behavior of Friction Welded AIsI 4140 and AIsI 304 in K_2sO-60% NaCl Mixture

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Journal of Materials science & Technology 2012年第10期28卷 895-904页

作者： N.Arivazhagan K.senthilkumaran s.narayanan K.Devendranath Ramkumar s.surendra s.Prakash school of Mechanical and Building sciences VIT University Department of Metallurgical and Materials Engineering Indian Institute of Technology Roorkee

Understanding the behavior of weldment at elevated temperatures and especially the corrosion behavior has become an object of scientific investigation recently. Investigation has been carried out on friction welded AIsI 4140 and AIsI 304 in molten salt of K2sO4-60% NaCI environment at 550, 600 and 650 ℃ under cyclic condition. The resulted oxide scales in the weldment have been characterized systematically by surface analytical techniques. From the results of the experiments~ it is observed that the scale thickness on low alloy steel side was higher than that on stainless steel side. Furthermore, weld interface has been found to be more susceptible to degradation than base metals due to inter diffusion of element across the interface and the formation of intermetallic compound. The influences of welding parameters and the temperature of exposure on the hot corrosion behavior of the weldment were discussed in this paper.

关键词： Friction Welding Dissimilar metals Hot corrosion

Design of internal model control based fractional order PID controller

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控制理论与应用（英文版） 2012年第3期10卷 297-302页

作者： T.VINOPRABA N.sIVAKUMARAN s.narayanan T.K.RADHAKRIsHNAN Department of Instrumentation and Control Engineering National Institute of TechnologyTiruchirappalli 620015India Department of Chemical Engineering National Institute of TechnologyTiruchirappalli 620015India

This article presents a design of the internal model control （IMC） based single degree of freedom （sDF） fractional order （FO） PID controller with a desired bandwidth specification for a class of fractional order system （FOs）. The drawbacks of the sDF FO-IMC are eliminated with the help of the two-degree of freedom （TDF） FO PID controller. The robust stability and robust performance of the designed controller are analyzed using an example.

关键词： Fractional order PID controller Fractional order systems Model based control Robust control

Triton X-100辅助合成多级孔道结构ZsM-5沸石催化剂(英文)

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催化学报 2014年第11期35卷 1892-1899页

作者： s.narayanan J.Judith Vijaya s.sivasanker sihai Yang L.John Kennedy Catalysis & Nanomaterials Research Laboratory Department of Chemistry Loyola College (Autonomous) National Centre for Catalysis Research Indian Institute of Technology school of Chemistry University of Nottingham University Park Materials Division School of Advanced Sciences Vellore Institute of Technology (VIT) University

ZsM-5 zeolite with a hexagonal cubic morphology was synthesized by a hydrothermal method using Triton X-100, a nonionic surfactant. The samples prepared with and without the surfactant were characterized by X-ray diffraction(XRD), Fourier transform infrared spectroscopy, N2 adsorption, high resolution transmission electron microscopy(TEM), high resolution scanning electron mi-croscopy, energy dispersive X-ray analysis, and NH3 temperature-programmed desorption. The XRD patterns confirmed the formation of a pure ZsM-5 crystalline phase without secondary phases. TEM images revealed that the hexagonal cubes were made of peanut-shaped nanoparticles with *** catalytic activity of the zeolite samples was evaluated using the selective oxidation of benzyl alcohol with tertiary-butyl hydrogen peroxide as the oxidant at 90 °C. The surfactant-assisted prep-aration yielded a zeolite that gave a higher conversion than the one prepared in the absence of the surfactant. The catalyst was retrieved and reused four times without significant loss in activity and selectivity.

关键词： ZsM-5催化剂 Triton 水热法合成 X-100 非离子表面活性剂 ZsM-5沸石高分辨透射电子显微镜傅立叶变换红外光谱

经Opuntia dilenii haw植物提取液绿色合成制备的纳米铝酸锌的催化性质(英文)

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催化学报 2013年第10期34卷 1951-1958页

作者： C.Ragupathi J.Judith Vijaya s.narayanan L.John Kennedy seeram Ramakrishna Catalysis and Nanomaterials Research Laboratory Department of ChemistryLoyola College Materials Division School of Advanced SciencesVellore Institute of Technology University Centre for Nanofibres and Nanotechnology National University of Singapore

Various nanosized zinc aluminate(ZnAl2O4) samples were prepared by a conventional and a mi- crowave method both with and without using Opuntia dilenii haw plant extract,and were charac- terized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),high resolution scanning electron microscopy(HRsEM),energy dispersion scanning(EDX),temperature dependent conductance measurements, thermoelectric power measurements, ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy,and photoluminescence *** formation of a pure ZnAl2O4 phase was confirmed by XRD and FT-IR.A change in morphology from nanosized plates to nanosized sheets with,respectively,the conventional and microwave heating methods was clearly shown by ***-Vis diffusion reflectance spectroscopy measured the band gaps of ZnAl2O4 nanosized plates and nanosized sheets as 3.5 and 3.9 eV,*** synthesized ZnAl2O4 was single crystalline and has three photoluminescence emissions at 482,528,and 540 ***2O4 nanosized sheets prepared by the microwave method showed higher catalytic activity for the oxida- tion of benzyl alcohol(85% conversion) than ZnAl2O4 nanosized plates prepared by the convention- al method(60% conversion).

关键词： Green synthesis Zinc aluminate spinel Microwave Optical property

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发掘在中国采购的潜力

商学院 2006年第7期 69-70页

作者：何杰明 Ananth s.narayanan 麦肯锡北京分公司麦肯锡芝加哥分公司

很多美国公司将采购活动转移到了廉价商品的来源地中国，但他们尚未充分发掘中国在采购方面所具有的潜力。尽管面临员工高流失率等种种困难，美国公司普遍计划加大在中国的采购力度。最近，我们访问了39家在中国设有采购办事处的美国公... 详细信息

很多美国公司将采购活动转移到了廉价商品的来源地中国，但他们尚未充分发掘中国在采购方面所具有的潜力。尽管面临员工高流失率等种种困难，美国公司普遍计划加大在中国的采购力度。最近，我们访问了39家在中国设有采购办事处的美国公司。据受访者估计，尽管有很多商品可以在中国采购，但他们仅从中国采购了其中的30％，而3年后这个比例将上升到50％。此外，受访者公司估计从中国采购产生的开支节省只实现了1／4的水平，而3年后这个比例可能上升为40％。

关键词：采购活动中国潜力发掘美国公司廉价商品受访者来源地采购方流失率

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发达国家与发展中国家稻米政策比较

中国稻米 2004年第5期10卷 47-48页

作者：林海庞乾林阮刘青 A.Eulati s.narayanan 中国水稻研究所杭州310006

世界各国政府都十分重视对大米行业的宏观调控.无论是发展中国家还是发达国家,为了保障粮食安全,对实行大米贸易自由化都非常谨慎.稻米在许多国家被认为是战略物资.但是,发达国家与发展中国家采取的政策在根本上有所不同.前者主要通过... 详细信息

世界各国政府都十分重视对大米行业的宏观调控.无论是发展中国家还是发达国家,为了保障粮食安全,对实行大米贸易自由化都非常谨慎.稻米在许多国家被认为是战略物资.但是,发达国家与发展中国家采取的政策在根本上有所不同.前者主要通过提高生产者价格来维持农民较高的收入,而后者趋于通过调节稻米生产税来确保广大贫穷消费者获得便宜的大米.

关键词：发达国家发展中国家稻米政策政府宏观调控

DNA测序、PCR-ssCP和phaB间接药敏实验检测结核分枝杆菌利福平耐药性的比较

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国际结核病与肺部疾病杂志 2003年第4期 125-132页

作者： C.Mani N.selvakumar V.Kumar s.narayanan P.R.narayanan 李传友 Tuberculosis Research Centre Chetput Chennai India

地点:印度Chennai结核病研究中心。目的:利用表型和基因型方法快速鉴定耐多药结核分枝杆菌。设计:对两种基因型分析方法,即 DNA测序法和聚合酶链反应-单链构象多态性(PCR-ssCP)法和一种表型分析方法,即噬菌体生物增殖法(phaB)进行了实... 详细信息

地点:印度Chennai结核病研究中心。目的:利用表型和基因型方法快速鉴定耐多药结核分枝杆菌。设计:对两种基因型分析方法,即 DNA测序法和聚合酶链反应-单链构象多态性(PCR-ssCP)法和一种表型分析方法,即噬菌体生物增殖法(phaB)进行了实验室内的标准化,并利用这三种方法测定101株RFPr和100株RFPs临床分离结核分枝杆菌的利福平耐药性。结果和结论:将三种方法的检测结果与常规间接药敏实验进行比较。DNA测序法的灵敏度和特异度分别为97％和100％,PCR-ssCP法为76％和100％,而phaB实验为97％和84％。DNA测序法的灵敏度和特异度高于其它两种方法。

关键词：结核分枝杆菌利福平耐药性 DNA测序 PCR-ssCP PhaB实验

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物料的加温与表面活性剂对磨矿效率的影响

河北冶金 1984年第4期 57-61页

作者： s.narayanan N.Raghunathan U.B.Nayak A.K.Lahiri 张学敏

表面活性剂在改善赤铁矿磨矿效率中的作用已进行了研究,研究中磨矿效率用破碎比度量。已发现,磨矿前的干燥可改善磨矿效率。加入表面活性剂对赤铁矿的硬度、显微硬度、破碎强度和湿磨效率的影响试验结果表明,分散剂比絮凝剂效果好,每种... 详细信息

表面活性剂在改善赤铁矿磨矿效率中的作用已进行了研究,研究中磨矿效率用破碎比度量。已发现,磨矿前的干燥可改善磨矿效率。加入表面活性剂对赤铁矿的硬度、显微硬度、破碎强度和湿磨效率的影响试验结果表明,分散剂比絮凝剂效果好,每种分散剂都具有使磨矿效率达最大值的监界浓度。

关键词：破碎比赤铁矿铁矿物磨矿效率水泥外加剂表面活性剂破碎强度物料

Multifunctional applications of gadolinium-doped cerium oxide(Ce1-xGdxO2-?) ceramics:A review

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Journal of Rare Earths 2024年第10期42卷 1817-1834页

作者： subhadip Das Rakesh Bhaskar Kannan Badri narayanan Department of Ceramic Engineering National Institute of Technology Rourkela school of Chemical Engineering Yeungnam University

Cerium oxide（CeO2）,or ceria,and its doped derivatives have been extensively studied for several decades and are well-known oxides valued for their unique structural properties and wide range of *** materials play a crucial role in sustainable development within *** modification through de fect e ngineering of the highly stable cubic fluorite phase enhances the versatility of this doped ceria to a new *** the numerous dopants of the CeO2matrix,ceria doped with gadolinium（Gd）,known as Ce1-xGdxO2-?（CGO）,is gaining popularity due to its *** introduction of defect-induced vacancies in the oxygen sublattice（V_o） and a change in the average valence of cerium(Ce3+/Ce4+) are primarily responsible for the improved performance compared to pristine *** materials are currently undergoing intensive research for potential use as electrolytes in intermediate-temperature solid oxide fuel cells（IT-sOFCs） and dense oxygen-permeable membranes（OPMs）.Additionally,they are being commercially utilized for power generation and oxygen *** materials are also attracting significant attention in various fields such as optics,photocatalysis,electrostriction,spintronics,gas sensing,electrocatalysis,and biomedical *** review paper aims to compile the latest contributions to CGO materials and comprehensively cover their various application *** crystal structure,defect equilibrium in Gd3+-doped CeO2,the origin of multifunctionality,and the prospects of these materials are also exclusively discussed.

关键词： Rare earths Photo/electrocatalysts Gas sensors spintronics Biomedicine