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Experimental Studies on the Self-Shielding Effect in Fissile Fuel Breeding Measurement in Thorium Oxide Pellets Irradiated with 14 Mev Neutrons

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Plasma Science and Technology 2013年第2期15卷 166-170页

作者： Mitul ABHANGI Nupur JAIN Rajnikant MAkWANA Sudhirsinh vALA Shrichand JAkHAR T. k. BASU C. v. S. rao Fusion Neutronics Laboratory Institute for Plasma ResearchBhat Gandhinagar-382428Gujarat India School of Nuclear Energy Pandit Deendayal Petroleum UniversityGandhinagarGujarat 382007 India

The 14 Mev neutrons produced in the D-T fusion reactions have the potential of breeding Uranium-233 fissile fuel from fertile material Thorium-232. In order to estimate the amount of U-233 produced, experiments are carried out by irradiating thorium dioxide pellets with neutrons produced from a 14 Mev neutron generator. The objective of the present work is to measure the reaction rates of 232Th ＋ in --＊ 233Th --＊ 2a^Pa --＊ 2a3U in different pellet thicknesses to study the self-shielding effects and adopt a procedure for correction. An appropriate assembly consisting of high-density polyethylene is designed and fabricated to slow down the high-energy neutrons, in which Thorium pellets are irradiated. The amount of fissile fuel （~3~U） produced is estimated by measuring the 312 kev gammas emitted by Protactinium-233 （half-life of 27 days）. A calibrated High Purity Germanium （HPGe） detector is used to measure the gamma ray spectrum. The amount of 233U produced by Th232 （n, ~） is calculated using MCNP code. The self-shielding effect is evaluated by calculating the reaction rates for different foil thickness. MCNP calculation results are compared with the experimental values and appropriate correction factors are estimated for self-shielding of neutrons and absorption of gamma rays.

关键词： 233U breeding fissile fuel MCNP 14 Mev neutron source

New Archaeological sites in the Gulf of Cambay,India

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Episodes 2003年第1期26卷 16-18页

作者： kathiroli, S. Badrinarayanan, S. rao, D.v. Sasisekaran, B. Sivakolundu, k.M. National Institute of Ocean Technol. Chennai India

India, with a coastline of over 7,500 km, is known to have engaged in maritime trade from the second half of the first millennium BC. Geophysical surveys conducted off the coast of Bombay, Laccadives, Tranquebar, kutch, Cambay, kaveripattinam and visakapatnam have recorded shipwrecks, submerged cities, ports and channels. It is highly probable that the shelf off the Andhra, kerala, Gujarat and Tamil Nadu coasts, if properly surveyed, will yield not only vestiges of prehistoric man and his tools but also submerged river channels and ports. A preliminary survey of the Gulf of Cambay with side-scan sonar soundings and a sub-bottom profiler revealed unnatural features. Further exploration through dredging brought to light artefacts that bore testimony to human activity.

关键词：考古遗址坎贝湾印度海岸线海上贸易人类活动

Stress corrosion cracking behaviour of 7xxx aluminum alloys: A literature review

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Transactions of Nonferrous Metals Society of China 2016年第6期26卷 1447-1471页

作者： A.C.UMAMAHESHWER rao v.vASU M.GOvINDARAJU k.v.SAI SRINADH Department of Mechanical Engineering National Institute of Technology WarangalWarangal 506004India Nonferrous Materials Technology Development Centre Hyderabad-500058500005India

Stress corrosion cracking （SCC） is degradation of mechanical properties under the combined action of stress and corrosive environment of the susceptible material. Out of eight series of aluminium alloys, 2xxx, 5xxx and 7xxx aluminium alloys are susceptible to SCC. Among them, 7xxx series aluminium alloys have specific application in aerospace, military and structural industries due to superior mechanical properties. In these high strength 7xxx aluminium alloys, SCC plays a vital factor of consideration, as these failures are catastrophic during the service. The understanding of SCC behaviour possesses critical challenge for this alloy. The main aim of this review paper is to understand the effect of constituent alloying elements on the response of microstructural variation in various heat-treated conditions on SCC behavior. Further, review was made for improving the SCC resistance using thermomechanical treatments and by surface modifications of 7xxx alloys. Apart from a brief review on SCC of 7xxx alloys, this paper presents the effect of stress and pre-strain, effect of constituent alloying elements in the alloy, and the effect of environments on SCC behaviour. In addition, the SCC behaviours of weldments, 7xxx metal matrix composites and also laser surface modifications were also reviewed.

关键词： 7xxx aluminum alloy stress corrosion cracking heat treatment microstructure corrosive environment thermomechanical treatment

Consequence of reinforced SiC particles and post process artificial ageing on microstructure and mechanical properties of friction stir processed AA7075

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Defence Technology（防务技术） 2020年第5期16卷 1039-1050页

作者： H.A.Deore A.Bhardwaj A.G.rao J.Mishra v.D.Hiwarkar Department of Metallurgical and Materials Engineering Defence Institute of Advanced TechnologyPune411025India Naval Material Research Laboratory(NMRL) Defence Research Development OrganizationMinistry of DefenceAmbarnath414006India

Friction stir processing and post process artificial ageing was successfully carried out on AA7075 with and without reinforcement of SiC particles producing defect free processed zone with uniform distribution of filler *** of SiC particle reinforcement and artificial ageing times on the microstructural modifications was characterized using optical and electron microscopy,electron backscattered diffraction and X-Ray ***,impact and wear tests were carried out to investigate mechanical behaviour before and after *** of SiC particles during FSP and subsequent age hardening treatment brought about nearly twofold increase in hardness and impact toughness values by the combined effect of grain refinement,Zener pinning,dispersion strengthening and precipitation *** improvement in wear resistance in terms of wear loss was also observed after processing compared to the reference material *** surface of post FSP age hardened AA7075 alloy exhibited features of ductile fracture during Charpy impact test.

关键词： Friction stir processing EBSD Impact toughness Post process age hardening Zener pinning

Design of Multi-valued Logic Circuit Using Carbon Nano Tube Field Transistors

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Computers, Materials & Continua 2022年第12期73卷 5283-5298页

作者： S.v.Ratankumar L.koteswara rao M.kiran kumar Department of Electronics and Communication Engineering Koneru Lakshmaiah Education FoundationAziz NagarHyderabad500075TelanganaIndia Department of Electronics and Communication Engineering RGM College of Engineering and TechnologyNandyal518501Andhra PradeshIndia Department of Electrical and Electronics Engineering Koneru Lakshmaiah Education FoundationVaddeswaramGuntur522502Andhra PradeshIndia

The design of a three-input logic circuit using carbon nanotube field effect transistors(CNTFETs)is *** logic must be an exact replacement for dual logic since it performs straightforwardly in digital devices,which is why this design is so popular,and it also reduces chip area,both of which are examples of circuit *** proposed module we have investigated is a triple-logic-based one,based on advanced technology CNTFETs and an emphasis on minimizing delay times at various values,as well as comparisons of the design working with various load *** the proposed design with the existing design,the delay times was reduced from 66.32 to 16.41 ps,i.e.,a 75.26%***,the power dissipation was not optimized,and increased by 1.44%compared to the existing *** number of transistors was also reduced,and the product of power and delay(P∗D)achieved a value of 0.0498053 *** improvement at 1 v was also achieved.A load capacitance(fF)was measured at different values,and the average delay measured for different values of capacitance had a maximum of 83.60 ps and a minimum of 22.54 ps,with a range of 61.06 *** power dissipations ranged from a minimum of 3.38μW to a maximum of 6.49μ*** on these results,the use of this CNTFET half-adder design in multiple Boolean circuits will be a useful addition to circuit design.

关键词： Carbon nanotube field effect transistor(CNTFET) multivalued logic(MvL) ternary adder Hewlett simulation program with integrated circuit emphasis(HSPICE) chirality(nm) adder

Evaluation of Large Amplitude Free vibration Behavior of Moderately Thick Square Plates Using Coupled Displacememt Field Method

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仪器仪表学报 2013年第S1期34卷 171-177页

作者： k.Meera Saheb C.Shasikanth G.venkateswara rao v.Suresh Babu Department of Mechanical Engineering University college of engineering Department of Mechanical Engineering MallaReddy College of Engineering Hyderabad Department of Mechanical Engineering vardhaman college of engineering Shamshabad Department of Mechanical Engineering

A simple and efficient coupled displacement field method is developed to study the large amplitude free vibration behavior of the moderately thick square plates.A single term trigonometric admissible displacement field is assumed for one of the variables,say,the total rotations(in both X,Y directions).Making use of the coupling equation,the spatial variation for the lateral displacement field is derived in terms of the total *** coupled displacement field method makes the energy formulation to contain half the number of unknown independent coefficients,in the case of a square plate,contrary to the conventional RayleighRitz *** lesser number of undetermined coefficients significantly simplifies the vibration *** expressions for the linear and nonlinear fundamental frequency parameters for the all edges simply supported moderately thick square plates are *** numerical results obtained from the present formulation are in very good agreement with those obtained from the existing literature.

关键词： vibration behavior coupled displacement field thick square plates

Petrogenesis of carbonatitic lamproitic dykes from Sidhi gneissic complex,Central India

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Geoscience Frontiers 2018年第2期9卷 531-547页

作者： M.Satyanarayanan D.v.Subba rao M.L.Renjith S.P.Singh E.v.S.S.k.Babu M.M.korakoppa CSIR-National Geophysical Research Institute Hyderabad 500007India Geological Survey of India Hyderabad 500068India Department of Geology Bundelkhand UniversityJhansi 284128India NCEGR Geological Survey of IndiaBengaluru 560070India

Petrographic, mineral chemical and whole-rock geochemical characteristics of two newly discovered lamproitic dykes(Dyke 1 and Dyke 2) from the Sidhi Gneissic Complex(SGC), Central India are presented here. Both these dykes have almost similar sequence of mineral-textural patterns indicative of:(1) an early cumulate forming event in a deeper magma chamber where megacrystic/large size phenocrysts of phlogopites have crystallized along with subordinate amount of olivine and clinopyroxene;(2) crystallization at shallow crustal levels promoted fine-grained phlogopite, k-feldspar, calcite and Fe-Ti oxides in the groundmass;(3) dyke emplacement related quench texture(plumose k-feldspar, acicular phlogopites) and finally(4) post emplacement autometasomatism by hydrothermal fluids which percolated as micro-veins and altered the mafic phases. Phlogopite phenocrysts often display resorption textures together with growth zoning indicating that during their crystallization equilibrium at the crystal-melt interface fluctuated multiple times probably due to incremental addition or chaotic dynamic self mixing of the lamproitic magma. Carbonate aggregates as late stage melt segregation are common in both these dykes, however their micro-xenolithic forms suggest that assimilation with a plutonic carbonatite body also played a key role in enhancing the carbonatitic nature of these dykes. Geochemically both dykes are ultrapotassic(k_2 O/Na_2 O: 3.0-9.4) with low CaO, Al_2 O_3 and Na_2 O content and high SiO_2(53.3-55.6 wt.%)and k_2 O/Al_2 O_3 ratio(0.51-0.89) characterizing them as high-silica lamproites. Inspite of these similarities, many other features indicate that both these dykes have evolved independently from two distinct magmas. In dyke 1, phlogopite composition has evolved towards the minette trend(Al-enrichment) from a differentiated parental magma having low MgO, Ni and Cr content; whereas in dyke 2, phlogopite composition shows an evolutionary affinity towards the lamproit

关键词： Lamproite Phlogopite Carbonate aggregates Metasomatized mantle Sidhi Gneissic Complex Central India

Arsenic Removal from Contaminated Water by various Physicochemical Processes

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Arsenic Removal from Contaminated Water by Various Physicoch...

Deep convolutional neural network models for weed detection in polyhouse grown bell peppers

作者： Pandu ranga rao Nzanthung Ngullie A.k.Golder Pranab kumar Ghosh the Department of Civil Engineering Indian Institute of Technology the Department of Chemical Engineering Indian Institute of Technology

Efficiency of ion exchange, electro membrane, and electrochemical ion-exchange(EIX) processes on arsenic removal were evaluated in laboratory. Batch studies were performed with chloride(IRA410) as well as hydroxyl(modified IRA410) exchangeable forms of anion exchange resins(AER), whereas, column study was done with only hydroxyl exchangeable AER to evaluate its performance on arsenic removal. A plate and frame type electrolytic cell with ruthenium dioxide coated titanium plates(RuO/Ti) as anode, and stainless steel plates as cathode, was fabricated to do experiment to evaluate the performance on arsenic removal by electro membrane as well as EIX processes. Though, As(v) removal was significant during batch kinetic study, As(III) removal was poor by both the AER. Breakthrough curves were developed by passing As(v) contaminated water at a flow rate of 5 ml/min through 3 different bed depths of 5 cm, 7.5 cm, and 10 cm of modified IRA410 columns having 1 cm internal diameter. The columns could efficiently remove from 500 μg/l of As(v) contaminated water to below 10 μg/l. In electro membrane process, effects of electrolyte concentration, effects of applied voltage, and initial concentration of As(v) were evaluated. EIX process was found to be inefficient in removing As(v) from contaminated water.

关键词： Arsenic ion-exchange EIX BDST

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Artificial Intelligence in Agriculture 2022年第1期6卷 47-54页

作者： A.Subeesh S.Bhole k.Singh N.S.Chandel Y.A.Rajwade k.v.R.rao S.P.kumar D.Jat ICAR-Central Institute of Agricultural Engineering(CIAE) BhopalMadhya PradeshIndia

Conventional weed management approaches are inefficient and non-suitable for integration with smart agricultural *** identification and classification of weeds can play a vital role in weed management contributing to better crop *** and smart spot-spraying system's efficiency relies on the accuracy of the computer vision based detectors for autonomous weed *** the present study,feasibility of deep learning based techniques(Alexnet,GoogLeNet,Inceptionv3,Xception)were evaluated in weed identification from RGB images of bell pepper *** models were trained with different values of epochs(10,20,30),batch sizes(16,32),and hyperparameters were tuned to get optimal *** overall accuracy of the selected models varied from 94.5 to 97.7%.Among the models,Inceptionv3 exhibited superior performance at 30-epoch and 16-batch size with a 97.7%accuracy,98.5%precision,and 97.8%*** this Inception3 model,the type 1 error was obtained as 1.4%and type II error was 0.9%.The effectiveness of the deep learning model presents a clear path towards integrating them with image-based herbicide applicators for precise weed management.

关键词： Bell pepper Computer vision Convolutional neural networks Deep learning Weed identification