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Characterization of Compactness of Rust Layers on Weathering Steels by an Adsorption/Dehydration Test of Ethanol

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Acta Metallurgica Sinica(English Letters) 2020年第6期33卷 846-856页

作者： Lujun Zhou Shanwu Yang Yi Dong Wenhua Zhang Jianwen Ding Guoliang Liu Chengjia Shang Raja devesh kumar Misra Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Department of Metallurgical Materials and Biomedical EngineeringUniversity of Texas at El PasoEl Paso.TX 79968 USA

A new method for evaluating the compactness of rust layers on steels has been proposed in the present study. The method includes adsorption and dehydration process of anhydrous ethanol. The protective ability of rust layers can be qualitatively reflected by the adsorption/dehydration rates. The specific surface area and porosity of rust layers can be calculated by a quantitative model. The results from the present method are consistent with electrochemical tests, N2 adsorption and X-ray diffraction analysis. The method characterizes the compactness of rust layers rather than that of corrosion products removed from the metal surfaces, which is generally practiced in classic N2 adsorption method. Furthermore, the method can reflect the compactness of inner rust layers, to which N2 adsorption is unavailable. The method provides a new approach for the study of rust layers.

关键词： Weathering steel Rust layers Ethanol adsorption/dehydration Specific surface area

Hydrogen trapping and electrochemical corrosion behavior of V–N microalloyed X80 pipeline steels consisting of acicular ferrite and polygonal ferrite

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Journal of Iron and Steel Research International 2022年第10期29卷 1683-1693页

作者： Ming-ming Wang Xiu-hua Gao Li-ying Song Cheng-lin Zhu Lin-xiu Du Raja devesh kumar Misra State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina Laboratory for Excellence in Advanced Steel Research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl PasoTX79968USA

Hydrogen trapping behavior of V–N microalloyed X80 pipeline steels was studied by means of hydrogen permeation and hydrogen induced cracking(HIC)*** addition,the electrochemical performance of the steels in 3.5 wt.%NaCl solution was *** indicated that the microstructure of experimental steels mainly consisted of acicular ferrite and polygonal ferrite(PF).When the fraction of PF was 9.1%and 30.4%,hydrogen effective diffusion coefficient was 1.624×10^(−6) and 3.121×10^(−6) cm^(2)/s,*** pipeline steels were not susceptible to *** potential hydrogen traps distributed in homogeneous dispersion were conducive to high HIC *** increasing the fraction of PF from 9.1%to 30.4%,the corrosion current density increased from 5.39×10^(−6) to 9.49×10^(−6) A cm^(−2),the corrosion potential decreased from−0.48 to−0.57 V,and the charge transfer resistance decreased from 2301 to 2068Ωcm^(2),*** fraction of PF was disadvantageous for corrosion resistance because of galvanic corrosion.

关键词： Pipeline steel V-N microalloying Hydrogen induced cracking susceptibility Hydrogen permeation Electrochemical corrosion

Microstructural Evolution and Properties of a High Strength Steel with Different Direct Quenching Processes

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Journal of Iron and Steel Research International 2015年第4期22卷 344-351页

作者： Feng LU Chao WANG Long L Zhao-dong WANG Guo-dong WANG Raja devesh kumar MISRA State Key Laboratory of Rolling and Automation Northeastern University Department of Metallurgical and Materials Engineering University of Texas at El Paso

A high strength low alloy steel with low carbon equivalent was selected for simulating online direct quench- ing and coiling （DQ-C） process. The influence of stop quenching temperature on mechanical properties and micro- structures was studied and compared with normal direct quenching and tempering （DQ-T） process. The study con- firmed that required mechanical properties were obtained for both the processes. Properties of the experimental steel with DQ-C process could reach the same level as that of DQ-T process in general. In the DQ-C process, strength de- creased with increase in stop quenching temperature. Martensite was obtained and experienced an aging process at stop quenching temperature below Mi. On fast cooling below Mi, martensite was partially transformed and carbon partitioning occurred during slow cooling. The reduction in solid solution carbon and increased amount of retained austenite led to lower strength compared with the DQ-T process. DQ-C process was more favorable for microalloy carbide precipitation. However, impact toughness under different cooling conditions was adequate because of low car- bon equivalent and refined microstructure.

关键词： high strength steel direct quenching slow cooling carbon partitioning precipitation

Hot Deformation Behavior and Microstructural Characteristics of Ti–46Al–8Nb Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第9期31卷 933-944页

作者： Tian-Rui Li Guo-Huai Liu Mang Xu Tian-Liang Fu Yong Tian Ra-Ja devesh kumar Misra Zhao-DongWang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Laboratory for Excellence in Advanced Steel Research Department of MetallurgicalMaterials and BiomedicalEngineeringUniversity of Texas at E1 PasoE1 PasoTX 79968-0521USA

Hot deformation behavior, microstructural evolution and flow softening mechanism were investigated in Ti-46A1-8Nb alloy via isothermal compression approach. The true stress-strain curves exhibited typical work hardening and flow softening, in which the dependence of the peak stress on temperature and strain rate was obtained by hyperbolic sine equation with Zener-Hollomon （Z） parameter, and the activation energy was calculated to be 446.9 kJ/mol. The microstructural analysis shows that the alternate dark and light deformed ribbons of Al-rich and Nb-rich regions appeared and were associated with local flow involving solute segregation. The Al segregation promoted flow softening mainly arising from the recrystaUization of V phase with low stacking fault energy. The coarse recrystallized 7 and several massive phase were observed at grain boundaries. While in the case of Nb segregation, t/B2 phase harmonized bending of lamellae, combined with the growth of recrystallized γ grains and α ＋ β ＋ γ→α＋ γ transition under conditions of temperature and stress, leading to the breakdown of α2/γ lamellar colony. During the hot compression process, gliding and dissociation of dislocations occurred in γ phase that acted as the main softening mechanism, leading to extensive γ twins and cross twins in α/γ lamellae and at grain boundaries. In general, homogeneous microstructure during the hot defor- mation process can be obtained in TiAl alloy with high Nb addition and low Al segregation. The deformation substructures intrinsically promote the formability of Ti--46Al-8Nb alloy.

关键词： Titanium aluminides Deformation behavior Activation energy Dynamic recrystallization Local flow softening

Critical Review on Balanites aegyptiaca Delile:Phytoconstituents,Pharmacological Properties and Nanointerventions

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Chinese Journal of Integrative Medicine 2024年第7期30卷 653-663页

作者： Surendra kumar Gautam Rakesh kumar Paul devesh M.Sawant Amita Sarwal Kaisar Raza Department of Pharmacy School of Chemical Sciences and PharmacyCentral University of RajasthanBandarsindriAjmerRajasthan305817India University Institute of Pharmaceutical Sciences Panjab UniversityChandigarh160014India

Balanites aegyptiaca Delile(BA)is an enduring xerophytic woody and spinous flowering tree and is commonly known as desert date or Ingudi(Hingot).It belongs to the family Zygophyllaceae,which is specific to be drought areas of Nigeria,Africa,South Asia and India(Rajasthan).In Ayurveda,this traditional medicinal plant is reported for the management of jaundice,syphilis,yellow fever,metabolic disorders,liver,and spleen *** main aim of the review is to compile its medicinal uses and further advancements to showcase the promises inherited in various parts of the plant for the benefit of *** per the literature survey,various researchers have focused on the detailed investigation of BA including the phytopharmacological evidence,chemical constituents,nano-formulations,commercialized products,and clinical *** remarkable scaffolds and isolated compounds like diosgenin,yamogenin,balanitin1/2,balanitin 3,bal4/5,bal6/7,rutin-3-glycosides,3,7-diglycosides,(3,12,14,16)–(12-hydroxycholest-5-ene-3,16-diyl-bis)-D-glucopyranoside and balanitoside have been ***,this traditional plant has been scientifically proven by in vitro and in *** on the complete review of this plant,most of the compounds have been isolated from the fruit and kernel ***,based on the literature,a histogram was developed for pharmacological activity in which antidiabetic study was found to be more compared to other pharmacological *** a spinous desert dates,this plant needs to be explored more to bring out newer phytochemicals in the management of various diseases.

关键词： Delile desert date phytochemicals nano-phytopharmaceutical pharmacological activities traditional medicine

Advancements in three-dimensional titanium alloy mesh scaffolds fabricated by electron beam melting for biomedical devices: mechanical and biological aspects

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Science China Materials 2018年第4期61卷 455-474页

作者： Krishna Chaitanya Nune Shujun Li R. devesh kumar Misra Biomaterials Science and Engineering Laboratory Metallurgical Materials and Biomedical Engineering Department University of Texas at El Paso TX 79968 USA Institute of Metals Research Chinese Academy of Sciences Shenyang 11016 China

We elucidate here the process-structure-property relationships in three-dimensional（3 D） implantable titanium alloy biomaterials processed by electron beam melting（EBM） that is based on the principle of additive manufacturing. The conventional methods for processing of biomedical devices including freeze casting and sintering are limited because of the difficulties in adaptation at the host site and difference in the micro/macrostructure, mechanical, and physical properties with the host tissue. In this regard, EBM has a unique advantage of processing patient-specific complex designs, which can be either obtained from the computed tomography（CT） scan of the defect site or through a computeraided design（CAD） program. This review introduces and summarizes the evolution and underlying reasons that have motivated 3 D printing of scaffolds for tissue *** overview comprises of two parts for obtaining ultimate functionalities. The first part focuses on obtaining the ultimate functionalities in terms of mechanical properties of 3 D titanium alloy scaffolds fabricated by EBM with different characteristics based on design, unit cell, processing parameters, scan speed, porosity, and heat treatment. The second part focuses on the advancement of enhancing biological responses of these 3 D scaffolds and the influence of surface modification on cell-material interactions. The overview concludes with a discussion on the clinical trials of these 3 D porous scaffolds illustrating their potential in meeting the current needs of the biomedical industry.

关键词： Electron beam melting 3D printing tissue engineering mechanical properties biocompatibility

Stumbling Blocks in Cloud Computing Adoption Pathway： A Charter

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Computer Technology and Application 2013年第12期4卷 635-642页

作者： devesh kumar Harsh Vardhan Samalia Piyush Verma Hergovind Singh Faculty of Management Sciences & Liberal Arts Shoolini University Solan 173229India Rajiv Gandhi Indian Institute of Management Shillong 793014 India L.M. Thapar School of Management Thapar University Patiala 147004 India Maulana Azad National Institute of Technology Bhopa1462051 India

Cloud computing is currently an embryonic domain in the area of information technology that possesses the power of transforming the way information technology （IT） services are delivered and maintained in the business world. Pay as per the usage kind of cost structure coupled with delivery of computing services through internet makes cloud computing an exciting and potential growth oriented information technology model compared with conventional computing services delivery models. Various additional features like scalability, flexibility and easy deployment process creates a window for the organizations even relatively smaller in size to get benefitted by the highly advanced ＆ modern technologies without incurring substantial cost. In spite of so many benefits of this new delivery model, concerns are beginning to grow about how safe an environment it is. Despite of all the hype surrounding the cloud, enterprise customers are still reluctant to deploy their business in the cloud. Security is one of the major issues which reduces the growth of cloud computing and complications with data privacy and data protection continue to plague the market. Other related concerns associated with the adoption of cloud computing include trust on service providers, loss of control and compliance issues. This paper is an attempt to explore security ＆ trust issues linked with cloud computing adoption in the Small and Medium Enterprises （SME） sector.

关键词： Cloud computing privacy security and SME.

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一位印度青年眼中的印度制造 011

Investigating Approaches of Data Integrity Preservation for Secure Data Aggregation in Wireless Sensor Networks

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作者： devesh kumar 柳森

devesh　kumar，印度“85后”，来自印度北部Uttar　Pradesh州的Baddi市，一座距离印度首都新德里5英里的高科技城市。在印度国内完成基础教育至高等教育后，主修财务、审计、公司法的他，取得了印度的注册会计师资格。2014年9月，Deves...

devesh　kumar，印度“85后”，来自印度北部Uttar　Pradesh州的Baddi市，一座距离印度首都新德里5英里的高科技城市。在印度国内完成基础教育至高等教育后，主修财务、审计、公司法的他，取得了印度的注册会计师资格。2014年9月，devesh因所供事的跨国公司的“全球财务运营领?

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Journal of Information Security 2014年第1期5卷 1-11页

作者： Vivaksha Jariwala Vishal Singh Prafulla kumar devesh C. Jinwala Department of Computer Engineering C. K. Pithawalla College of Engineering and Technology Surat India Department of Electronics and Information Technology Ministry of Communications and Information Technology India S. V. National Institute of Technology Ichchanath Surat India

Wireless Sensor Networks (WSNs) typically use in-network processing to reduce the communication overhead. Due to the fusion of data items sourced at different nodes into a single one during in-network processing, the sanctity of the aggregated data needs to be ensured. Especially, the data integrity of the aggregated result is critical as any malicious update to it can jeopardize not one, but many sensor readings. In this paper, we analyse three different approaches to providing integrity support for SDA in WSNs. The first one is traditional MAC, in which each leaf node and intermediate node share a key with parent (symmetric key). The second is aggregate MAC (AMAC), in which a base station shares a unique key with all the other sensor nodes. The third is homomorphic MAC (Homo MAC) that is purely symmetric key-based approach. These approaches exhibit diverse trade-off in resource consumption and security assumptions. Adding together to that, we also propose a probabilistic and improved variant of homomorphic MAC that improves the security strength for secure data aggregation in WSNs. We carry out simulations in TinyOS environment to experimentally evaluate the impact of each of these on the resource consumption in WSNs.

关键词： In-Network Processing Integrity Message Authentication Code Secure Data Aggregation Wireless Sensor Networks