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Chinese Science bulletin 1997年第16期42卷 1372-1377页

作者： Zhao, JS Zhao, b rao, b Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China Nanjing Univ Dept Earth Sci Nanjing 210008 Peoples R China

To counter the lack of consensus of opinion on mineralizations of Ta, Nb and W which have genetic relationship to fluorine-rich albite granite and the want of experimental evidence at present, some experiments reported in this study were carried out. The purpose of this study is to explain the genetic connection of Ta, Nb and W ore deposits and possible mechanism of their mineralization with the aid of the experimental results.

关键词： partition behaviour of Ta Nb and W process of crystallization differentiation of magma.

Chloride binding and time-dependent surface chloride content models for fly ash concrete

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Frontiers of Structural and Civil Engineering 2016年第1期10卷 112-120页

作者： S. MUTHULINGAM b. N. rao Department of Civil Engineering SSN College of Engineering Kalavakkam 603 110 India Structural Engineering Division Department of Civil Engineering Indian Institute of Technology Madras Chennai 600 036 India

Corrosion of embedded rebars is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. Such environments can be attributed to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. Chloride ingress into concrete, essential for inducing rebar corrosion, is a complex interaction between many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely： 1） surface chloride content under tidal exposure condition; and 2） chloride binding. First, inconsistencies in surface chloride content and chloride binding models reported in literature, due to them not being in line with past research studies, are pointed out. Secondly, to avoid such inconsistencies, surface chloride content and chloride binding models for fly ash concrete are proposed based upon the experimental work done by other researchers. It is observed that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词： binding isotherms chloride ingress concrete fly ash surface chloride content

Significance of Alloying Element Levels in Realizing the Specified Tensile Properties in 18 Wt % Nickel Maraging Steel

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Materials Sciences and Applications 2011年第8期2卷 1116-1120页

作者： Muktinutalapati nageswara rao Krishnan Sivasubramanian 不详

Among the various grades of commercially available 18 wt. % nickel maraging steels, the one with nominal 0.2% proof strength in the range 1700-1750 MPa is the most commonly used and is distinguished by an excellent combination of high strength and high fracture toughness. The main alloying elements are nickel, cobalt, molybdenum and titanium. The first three of these are present at relatively high concentrations in the chemical composition. The high cost of these metals leads to a high cost of production and this becomes a deterrent to extensive use of the steel. In the present study, an attempt was made to produce the steel by pegging the levels of these alloying elements in the lower half of the specified range. The objective was to save on the raw material cost, while still conforming to the specification. The steel so produced could not, however, attain the specified tensile properties after final heat treatment. The observed behavior is explained based on the role played by the different alloying elements in driving the precipitation hardening reaction.

关键词： 18 % Ni Maraging Steel Chemical Composition Alloying Elements Age Hardening Tensile Properties

Study on Factors Effecting Weld Pool Geometry of Pulsed Current Micro Plasma Arc Welded AISI 304L Austenitic Stainless Steel Sheets Using Statistical Approach

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Journal of Minerals and Materials Characterization and Engineering 2012年第8期11卷 790-799页

作者： Kondapalli Siva Prasad Chalamalasetti Srinivasa rao Damera nageswara rao Centurion University of Technology & Management Odissa INDIA Department of Mechanical Engineering Andhra University Visakhapatnam INDIA Department of Mechanical Engineering Anil Neerukonda Institute of Technology & Sciences Visakhapatnam INDIA

Pulsed current Micro Plasma Arc Welding is used to joint thin sheets of AISI 304L sheets, which are used in manufacturing of metallic bellows and diaphragms. In this article the effects of pulsing current parameters on weld pool geometry namely front width, back width, front height and back height of pulsed current micro plasma arc welded AISI 304L stainless steel sheets was analyzed. Four factors, five levels, central composite design was used to develop mathematical models, incorporating pulsed current parameters and weld pool geometry. The mathematical models have been developed by Response Surface Method. The adequacy of the models was checked by ANOVA technique. Variation of output responses with input process variables are discussed. by using the developed mathematical models, weld pool geometry parameters can be predicted.

关键词： Pulsed Current Micro Plasma Arc Welding Mathematical Model Aisi 304l Stainless Steel Weld Pool Geometry ANOVA

Study on Effect of Welding Speed on Micro Structure and Mechanical Properties of Pulsed Current Micro Plasma Arc Welded Inconel 625 Sheets

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Journal of Minerals and Materials Characterization and Engineering 2012年第10期11卷 1027-1033页

作者： Chalamalasetti Srinivasa rao Kondapalli Siva Prasad Damera nageswara rao Department of Mechanical Engineering Anil Neerukonda Institute of Technology & Sciences Visakhapatnam India Department of Mechanical Engineering AU College of Engineering Andhra University Visakhapatnam India Vice Chancellor Centurion University of Technology & Management Odisha India

Nickel alloys had gathered wide acceptance in the fabrication of components which require high temperature resistance and corrosion resistance, such as metallic bellows used in expansion joints used in aircraft, aerospace and petroleum industry. Micro Plasma Arc Welding (MPAW) is one of the important arc welding processes commonly using in fabric- cation of Nickel alloys. In the present paper welding of Inconel 625 sheets using pulsed current micro plasma arc weld- ing was discussed. The paper mainly focuses on studying the weld quality characteristics like weld pool geometry pa- rameters, microstructure, grain size, hardness and tensile properties of Pulsed Current Micro Plasma Arc Welded In- conel 625 sheets at different welding speeds. Results reveals that at a welding speed of 260 mm/minute better weld quality characteristics can be obtained.

关键词： Pulsed Current Micro Plasma Arc Welding Inconel 625 Grain Size Hardness Tensile Properties

Application of Hooke &Jeeves Algorithm in Optimizing Fusion Zone Grain Size and Hardness of Pulsed Current Micro Plasma Arc Welded AISI 304L Sheets

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Journal of Minerals and Materials Characterization and Engineering 2012年第9期11卷 869-875页

作者： Kondapalli Siva Prasad Chalamalasetti Srinivasa rao Damera nageswara rao Associate Professor Department of Mechanical Engineering Andhra University Visakhapatnam INDIA Department of Mechanical Engineering Anil Neerukonda Institute of Technology & Sciences Visakhapatnam INDIA Vice Chancellor Centurion University of Technology & Management Odisha INDIA

AISI 304L is an austenitic Chromium-Nickel stainless steel offering the optimum combination of corrosion resistance, strength and ductility. These attributes make it a favorite for many mechanical components. The paper focuses on developing mathematical models to predict grain size and hardness of pulsed current micro plasma arc welded AISI 304L joints. Four factors, five level, central composite rotatable design matrix is used to optimize the number of experiments. The mathematical models have been developed by Response Surface Method (RSM) and its adequacy is checked by Analysis of Variance (ANOVA) technique. by using the developed mathematical models, grain size and hardness of the weld joints can be predicted with 99% confidence level. The developed mathematical models have been optimized using Hooke and Jeeves algorithm to minimize grain size and maximize the hardness.

关键词： Pulsed Current Micro Plasma Arc Welding AISI 304L Grain Size Hardness Hooke & Jeeves Algorithm

Effect of Hydrodynamic Conditions on Corrosion Inhibition of Cu-Ni(90/10)Alloy in Seawater and Sulphide Containing Seawater Using 1,2,3-benzotriazole

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Journal of Materials Science & Technology 2014年第1期30卷 65-76页

作者： b.V.Appa rao K.Chaitanya Kumar Department of Chemistry National Institute of Technology Warangal

Electrochemical studies of the effect of hydrodynamic conditions on corrosion inhibition of Cu-Ni （90/10） alloy in synthetic seawater and sulphide containing synthetic seawater by 1,2,3-benzotriazole （bTAH） are presented. Impedance, potentiodynamic polarization and cyclic voltammetric （CV） studies are employed in the present investigation. The studies are carried out by using Cu-Ni （90/10） alloy rotating disc electrode at different rotation speeds and at different immersion periods. Reynolds numbers at each rotation speed infer that the flow of seawater is laminar. With increasing rotation speed of the electrode immersed in seawater without sulphide and bTAH, both the charge transfer resistance （Rot） and film resistance （Rf^lm） are increased. However, in the presence of sulphide ions and without bTAH, both the Rot and Rf,m are found to decrease with increasing rotation speed at identical immersion periods. Interestingly, when bTAH is added to seawater or seawater containing sulphide, both the Rot and Rf,m are increased to such a great extent that an inhibition efficiency of 99.99% is obtained. In the presence of bTAH, the phase angle bode plots are more broadened and the maximum values of phase angle are increased to a value close to 90~ as the rotation speed is increased. The bTAH film is highly protective even under hydrodynamic condition also. Potentiodynamic polarization studies infer that bTAH functions as a mixed inhibitor under hydrodynamic conditions also. CV studies reveal that the protective bTAH film is stable even at anodic potentials of ＋850 mV vs Ag/AgCI.

关键词： Cu-Ni (90/10) alloy Rotating disc electrode Seawater Corrosion inhibition Electrochemical studies 1,2,3-benzotriazole

Implications for the lithospheric structure of Cambay rift zone,western India:Inferences from a magnetotelluric study

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Geoscience Frontiers 2020年第5期11卷 1743-1754页

作者： Nagarjuna Danda C.K.rao Amit Kumar P.Rama rao P.b.V.Subba rao Dr.K.S.Krishnan Geomagnetic Research Laboratory IIGAllahabad221505India Indian Institute of Geomagnetism New PanvelNavi Mumbai410218India Department of Geophysics Andhra UniversityVisakhapatnam530003India

broad-band and long-period magnetotelluric(MT)data were acquired along an east-west trending traverse of nearly 200 km across the Kachchh,Cambay rift basins,and Aravalli-Delhi fold belt(ADFb),western *** regional strike analysis of MT data indicated an approximate N59°E geoelectric strike direction under the traverse and it is in fair agreement with the predominant geological strike in the study *** decomposed transverse electric(TE)-and transverse magnetic(TM)-data modes were inverted using a nonlinear conjugate gradient algorithm to image the electrical lithospheric structure across the Cambay rift basin and its surrounding *** studies show a thick(~1-5 km)layer of conductive Tertiary-Mesozoic sediments beneath the Kachchh and Cambay rift *** resistive blocks indicate presence of basic/ultrabasic volcanic intrusives,depleted mantle lithosphere,and different Precambrian structural *** crustal conductor delineated within the ADFb indicates the presence of fluids within the fault zones,sulfide mineralization within polyphase metamorphic rocks,and/or Aravalli-Delhi sediments/*** observed conductive anomalies beneath the Cambay rift basin indicate the presence of basaltic underplating,volatile(CO2,H2 O)enriched melts and channelization of melt fractions/fluids into crustal depths that occurred due to plume-lithosphere *** variations in electrical resistivity observed across the profile indicate that the impact of Reunion plume on lithospheric structures of the Cambay rift basin is more dominant at western continental margin of India(WCMI)and thus support the hypothesis proposed by Campbell&Griffiths about the plume-lithosphere interactions.

关键词： Cambay rift Deccan basalts Magnetotellurics Partial melt Reunion plume

Weighted Probability Density Estimator with Updated bandwidths

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Journal of Systems Science & Complexity 2024年第2期37卷 886-906页

作者： WU Yi YU Wei WANG Xuejun PRAKASA rao b L S School of big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China School of big Data and Statistics Anhui UniversityHefei 230601China CR rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a class of weighted version of probability density *** is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or *** statistical results including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are established under some mild ***,the random weighted estimator is also *** numerical simulations and a real data analysis are presented to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical simulation probability density real data analysis updated bandwidths weighted estimator

Copy-Move Forgery Verification in Images Using Local Feature Extractors and Optimized Classifiers

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big Data Mining and Analytics 2023年第3期6卷 347-360页

作者： S.b.G.Tilak babu Ch Srinivasa rao University College of Engineering JNTU KakinadaKakinada 533003India. Department of ECE JNTUK UCEVizianagaram 535003India.

Passive image forgery detection methods that identify forgeries without prior knowledge have become a key research *** copy-move forgery,the assailant intends to hide a portion of an image by pasting other portions of the same *** detection of such manipulations in images has great demand in legal evidence,forensic investigation,and many other *** paper aims to present copy-move forgery detection algorithms with the help of advanced feature descriptors,such as local ternary pattern,local phase quantization,local Gabor binary pattern histogram sequence,Weber local descriptor,and local monotonic pattern,and classifiers such as optimized support vector machine and optimized *** proposed algorithms can classify an image efficiently as either copy-move forged or authenticated,even if the test image is subjected to attacks such as JPEG compression,scaling,rotation,and brightness ***,CASIA,and MICC datasets and a combination of CoMoFoD and CASIA datasets images are used to quantify the performance of the proposed *** proposed algorithms are more efficient than state-of-the-art algorithms even though the suspected image is post-processed.

关键词： copy move forgery detection image authentication passive image forgery detection blind forgery detection