Role of Chromium Content on the Microstructure and Mechanical Properties of Lanthana Based Ferritic ODS Steels

Ashwani Kumar,Bhagyaraj Jayabalan,Chetan Singh,Jayant Jain,Subrata Mukherjee,Krishanu Biswas,Sudhanshu S. Singh 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.4

In the current study, lanthana (La2O3) based oxide dispersion strengthened (ODS) ferritic steels (Fe–xCr–1Ti–1W–0.5L2O3,x = 14, 18, 22, and 26, in wt%) have been fabricated by mechanical alloying and spark plasma sintering. The role of chromium(Cr) content and maximum sintering temperature (1050 and 1100 °C) on the density, microstructure and mechanical propertiesof the ODS steels have been studied. TEM analysis of the alloy revealed the presence of nano-sized (2–8 nm) complexoxide particles, i.e., La–Ti–Cr–O. Mechanical properties were estimated in terms of micro-hardness, nano-hardness, Young’smodulus and compressive strength. The highest micro-hardness (988 ± 11.3 HV) and compressive strength (2322 ± 49 MPa)were exhibited by the alloy having 26 wt% Cr, sintered at 1100 °C. The contribution of dispersion strengthening towards thestrength was calculated to be the highest (~ 72%). Overall, increasing the Cr content improved both the room temperaturecompressive strength as well as the compressive fracture strain.

Survey on Content-based Image Retrieval and Texture Analysis with Applications

Ashwani Kr. Yadav,R. Roy,Vaishali,Archek Praveen Kumar 보안공학연구지원센터(IJSIP) 2014 International Journal of Signal Processing, Image Vol.7 No.6

Content-based image retrieval is a very important area of research nowadays. Content Based mage Retrieval (CBIR) is a technique which uses visual features of image such as color, shape, texture, etc. CBIR technologies provide a method to find images in large databases by using unique descriptors from a trained image. A lots of research works had been completed in the past decade to design efficient image retrieval techniques from the image or multimedia databases. Large number of retrieval techniques has been introduced, but there is no universally accepted feature extraction and retrieval technique available. In this paper, we present a study of various content-based image retrieval systems and their behaviour, texture analysis and various feature extraction with representation.

Spectroscopic Examination and Analysis of Unconfined Swirling Flames

Ashwani Gupta,Sean Archer,Kuniyuki Kitagawa 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.1

Spectroscopic techniques have been used to examine the dynamic behavior of unconfined swirling flows and flames under fuel-lean combustion conditions. Specific spectroscopic diagnostics used include 3-D stereo particle image velocimetry (PIV) for the flow field, optical emission spectroscopy for CH, OH and C2 chemiluminescence, and infrared thermometry for the temperature. The effect of the radial distribution of the combustion air swirl is examined under burning and non-burning conditions in an experimental double concentric swirl burner that simulates one swirl cup of a practical gas turbine combustor using propane as the fuel. Results show the roles of the co- and the counter-swirl distributions in a burner on the flow structure, both with and without combustion. Both the swirl distribution and combustion significantly influence the flow field, as well as the spatial distributions of CH, OH, C2, and the thermal field in flames. Combustion causes a significant increase in the velocity magnitudes and in the entrained mass flow rate for the co-swirl distribution.0

Selective fluorescence sensing of 3,5-dinitrosalicylic acid based on pyrenesulfonamide-functionalized inorganic/organic hybrid nanoparticles

Ashwani Kumar,이주영,김홍석 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.44 No.-

Pyrenesulfonamide-functionalized inorganic/organic hybrid Fe3O4@SiO2 nanoparticles were preparedfor the selective and sensitive detection of 3,5-dinitrosalicylic acid (3,5-DNSA) among a series ofaromatic carboxylic acids. The monomer fluorescence emission intensity of pyrene at 380 nm wasswitched off on interaction with 3,5-DNSA. The minimum detection limit for 3,5-DNSA was 10 nM in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES)–CH3CN (8:2; pH 7.4). The inorganic/organichybrid Fe3O4@SiO2 nanoparticles were characterized using Fourier-transform infrared spectroscopy,thermogravimetric analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and high-resolutiontransmission electron microscopy.

DEVELOPMENT OF BELT AND ROAD INITIATIVE: Assessment of Economic Implications for Regional Economies including India

Ashwani Bishnoi,Pravakar Sahoo 한국외국어대학교 인도연구소 2021 남아시아연구 Vol.27 No.1

China’s flagship project Belt and Road Initiative (BRI) launched in 2013 is meant to reshape global networks of transport infrastructure further integrating China with Asia, Europe and Africa having significant implications on trade, investment and economic and political ties of China vis-à-vis with other countries. The paper brings the present state of the project in terms of setting up of institutional capabilities and the infrastructure investment into BRI participating countries. It also highlights the impact assessment of BRI for China and draws the economic as well as strategic implications of the project on India. Overall, there has been significant increase in Chinese outward investment during the post- BRI announcement and most of the outward investment has been directed towards countries which are participating in BRI. With regard to the impact on China, it is found that the core industrial output of China has not experienced a revival post BRI announcement. On the trade front, no such evidence of increase in exports of China to the countries falling around BRI corridor is noted so far, and same for imports also from the resource seeking perspective. The possible implications for India is that the BRI project is going to put the Indian economy into a very challenging environment as both countries share the trade complementarities with the BRI participating regions.

EFFECT OF ELECTRIC FIELD, TEMPERATURE AND CORE DIMENSIONS IN III – V COMPOUND CORE – SHELL NANOWIRES

ASHWANI VERMA,Bahniman Ghosh,AKSHAY KUMAR SALIMATH 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.4

In this paper, we have used semiclassical Monte Carlo method to show the dependence of spinrelaxation length in III – V compound semiconductor core – shell nanowires on di®erent parameterssuch as lateral electric ¯eld, temperature and core dimensions. We have reported the simulationresults for electric ¯eld in the range of 0.5 – 10 kV/cm, temperature in the range of 77 – 300 K andcore length ranging from 2 nm to 8 nm. The spin relaxation mechanisms used in III – V compoundsemiconductor core – shell nanowire are D'yakonov – Perel (DP) relaxation and Elliott – Yafet (EY)relaxation. Depending upon the choice of materials for core and shell, nanowire forms two types ofband structures. We have used InSb – GaSb core – shell nanowire and InSb – GaAs core – shellnanowire and nanowire formed by swapping the core and shell materials to show all the results.

Increasing Efficiency for Energy Sustainability and Reduced Environmental Footprint

( Ashwani K Gupta ) 경남대학교 신소재연구소 2013 신소재연구 Vol.25 No.-

Increasing efficiency offers near term solution for energy sustainability and reduced environmental foot print. In power generation more than 60% of the energy is wasted so that only about 35 (characteristic) to 50% (high end) of the energy is used for chemical to electrical energy conversion. For given energy demand increase in energy conversion efficiency offers less energy use, reduced amounts of total pollutants including CO2 and increased energy sustainability. In this paper clean energy production form various kinds of fuels for sustainable energy production will be provided. Our ongoing efforts at the University of Maryland on various kinds of fuels (fossil, alternative and biomass and wastes) has allowed us to determine novel means for clean energy conversion at higher efficiency with minimal environmental footprint. It is now well understood that carbon dioxide (CO2) is a greenhouse gas that provides direct contributions to global warming of our plant. Although there are other contributors to global warming but the share of CO2 is significant. Most of the CO2 is produced from the combustion of fossil fuels and our use of fossil fuels has been increasing due to increased activity and population. The carbon during the combustion process is converted to CO2 with the subsequent release of thermal energy. In the USA most of the electricity is produced from fossil fuels, with coal being the highest. The demand for electricity continues to grow in the developed countries with significant more in some of the developing countries, such as China and India. This has resulted in dramatic increase in global ambient concentrations of CO2. Significant efforts are being pursued to curtail the emission of CO2 or capture and store it in order to maintain the ambient concentrations to some acceptable levels. The contributions to the CO2 emissions by fuel type in 2006 were 19.4% gas, 38.5% oil, and 41.7% coal. China is now the dominant emitter of CO2, having caught up with the USA in 2006 (5697 Mt for USA and 5606 MT for China), with the two countries accounting for 40.3% of the global emissions. Various goals have been proposed for the reduction guided by the desire to stabilize global CO2 concentrations at levels that would constrain the global temperature rise above pre-industrial levels to 2 degrees C. Temperature rise above this level from the climate change are projected to be severe. Clean energy harvesting from various kinds solid fuels including low grade fuels is a challenge as direct combustion of such fuels provide rather high and unacceptable levels of pollutants emission including smoke and particulates and the conversion efficiency to electric power is low. In addition all solid fuels results in fouling and deposition of the combustion chamber and heat exchange equipment resulting in decreased efficiency and performance. The health hazardous trace components and large amounts of char and tar produced results in low energy recovery efficiency. In an effort to develop clean and efficient combined heat and power system one must reform the solid fuel fuels to clean chemical energy at high efficiency. Advanced high temperature steam assisted gasification technology offers reforming of solid fuels (coal and wastes) to clean syngas fuel. In traditional gasification systems the solid fuel material is partly combusted with air under starved combustion conditions so that much of the carbon in the fuel is converted to carbon monoxide in the syngas. This process results in large amounts of char and tar and must be removed prior to the use of syngas in combustors and engines. In addition the process results in large amounts of nitrogen in the syngas so that the heating value of the syngas produced is rather low. The advanced gasification process provides enhanced reformation of solid fuel to syngas using ultra high temperature steam so that the solid biomass fuel is not combusted but rather converted to syngas with the simultaneous alleviation of nitrogen gas from the syngas. Furthermore the syngas produced is of high hydrogen content and minimum char and tar. Biomass and agricultural wastes offer much potential for its use to energy. The CO2 helps to grow biomass so that its grater use assists in both the CO2 problem and renewable energy utilization. Gasification of solid fuels is a good solution for not only the energy problem that also offers environmentally benign solution at high efficiency. In this presentation the production of clean fuels and electric power generation with specific role of renewable energy will be presented. Examples of advanced power generation will be provided that are focused on clean and efficient energy conversion with focus on efficiency and pollutants emission including CO2.

Molecular Characterization of Gastrothylax crumenifer (Platyhelminthes: Gastrothylacidae) from Goats in the Western Part of India by LSU of Nuclear Ribosomal DNA

Ashwani Kumar,Anshu Chaudhary,Chandni Verma,Hridaya Shanker Singh 대한기생충학열대의학회 2014 The Korean Journal of Parasitology Vol.52 No.6

The rumen parasite, Gastrothylax crumenifer (Platyhelminthes: Gastrothylacidae), is a highly pathogenic trematode parasite of goat (Capra hircus). It sucks blood that causes acute disease like anemia, and severe economic losses occur due to morbidity and mortality of the ruminant infected by these worms. The study of these rumen paramphistomes, their infection, and public health importance remains unclear in India especially in the western part of state Uttar Pradesh (U.P.), Meerut, India, where the goat meat consumption is very high. This paper provides the molecular characterization of G. crumenifer recovered from the rumen of Capra hircus from Meerut, U.P., India by the partial sequence of 28S rDNA. Nucleotide sequence similarity searching on BLAST of 28S rDNA from parasites showed the highest identity with those of G. crumenifer from the same host Capra hircus. This is the first report of molecular identification of G. crumenifer from this part of India.

Trends in Global Energy Use and Pinnacle Role of High Temperature Air Combustion (HiTAC)

( Ashwani K Gupta ) 경남대학교 신소재연구소 2012 신소재연구 Vol.24 No.-

The use of energy in both developing countries and developed countries continue to rise. Furthermore with the population increase and known reserves of fossil fuel resources worldwide, it is imperative that one must take strong strides for sustainable energy so that future generations can see the same or improved quality of life through efficient and cleaner use of energy. The energy use in different parts of the world varies significantly with the USA having 4.6% of the world population used about 22% of the world energy while India represented 17% of the world population and used only 5% of world energy in 2006. The use of energy is of paramount for increased GDP. The power plant efficiency can vary significantly (25 to 50%) so that much of the energy is lost in the conversion process. Improvements in energy efficiency offer significant savings in other resources. High temperature air combustion technology (HiTAC) offers significant benefits on energy savings while providing simultaneous benefits on pollution reduction, uniform thermal field in the combustion zone, low noise and improved quality of product from the process. Gains in energy efficiency from HiTAC offer significant benefits in industrial processes that are now implemented in many industrial furnaces worldwide. HiTAC has also been deployed for fuel reforming, hydrogen rich syngas production and volume distributed gas turbine combustion that show no flame color or environmentally benign green flame color instead of the more commonly observed hybrid color flame under gas turbine combustion conditions.

Analytical Design of Optimum FIR Digital Integrators

Ashwani Kumar,Balbir Kumar 대한전자공학회 1995 JTC-CSCC : Joint Technical Conference on Circuits Vol.- No.-