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Evaluation of hydro-chemistry in a phreatic aquifer in the Vindhyan Region, India, using entropy weighted approach and geochemical modelling

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Acta Geochimica 2023年第4期42卷 648-672页

作者： Ashutosh Mishra Aman rai Prabuddh Kumar Mishra Suresh Chand rai Department of Geography Delhi School of EconomicsUniversity of DelhiDelhi 110027India Department of Geography Shivaji CollegeUniversity of DelhiDelhi 110027India

Groundwater quality monitoring and geochemical characterization in the phreatic aquifer are critical for ensuring universal and equitable access to clean,reliable,and inexpensive drinking water for *** research was intended to investigate the hydrogeochemical attributes and mechanisms regulating the chemistry of groundwater as well as to assess spatial variation in groundwater quality in Satna district,*** accomplish this,the groundwater data comprising 13 physio-chemical parameters from thirty-eight phreatic aquifer locations were analysed for May 2020 by combining entropy-weighted water quality index(EWQI),multivariate statistics,geochemical modelling,and geographical information *** findings revealed that the groundwater is fresh and slightly *** was a significant concern as 57.89% of samples were beyond the permissible limit of the World Health *** dominance of ions were in the order of Ca^(2+)> Na^(+)> Mg^(2+)> K^(+) and HCO_(3)^(-)> SO_(4)^(2-)> Cl^-> NO_(3)^(-)> F^(-).Higher concentration of these ions is mainly concentrated in the northeast and eastern *** correlation analysis and principal component analysis(PCA) demonstrated that both natural and human factors regulate groundwater chemistry in the *** analysis of Q-mode agglomerative hierarchical clustering highlighted three significant water ***-HCO_3 was the most prevalent hydro-chemical facies in all three *** modelling through various conventional plots indicated that groundwater chemistry in the research region is influenced by the dissolution of calcite/dolomite,reverse ion exchange,and by silicate and halite *** data of the study area disclosed that 73.69% of the samples were appropriate for *** to high salinity,Magnesium(Mg^(2+)),Nitrate(NO_(3)^(-)),and Bicarbonate(HCO_(3)^(-)) concentrations,the north-central and north-eastern regions are particularly *** findings of the study m

关键词： Groundwater quality assessment EWQI Multivariate statistical analysis Geochemical modelling Hydrogeochemical processes Saturation index

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Machine auscultation: enabling machine diagnostics using convolutional neural networks and large-scale machine audio data

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Advances in Manufacturing 2019年第2期7卷 174-187页

作者： Ruo-Yu Yang Rahul rai Manufacturing and Design Lab (MAD Lab) University at Buffalo Buffalo NY USA

Acoustic signals play an essential role in machine state monitoring. Efficient processing of real-time machine acoustic signals improves production quality. However, generating semantically useful information from sound signals is an ill-defined problem that exhibits a highly non-linear relationship between sound and subjective perceptions. This paper outlines two neural network models to analyze and classify acoustic signals emanating from machines:(i) a backpropagation neural network (BPNN);and (ii) a convolutional neural network (CNN). Microphones are used to collect acoustic data for training models from a computer numeric control (CNC) lathe. Numerical experiments demonstrate that CNN performs better than the BP-NN.

关键词： Acoustic signal processing Machine performance Backpropagation neural network (BP-NN) Convolutional neural network (CNN)

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Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： Ranjeet rai R.R.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GRG HC CO and NO

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Soil organic carbon and phosphorus availability regulate abundance of culturable phosphate-solubilizing bacteria in paddy fields

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Pedosphere 2020年第3期30卷 405-413页

作者： Arvind KUMAR Lal Chand rai Molecular Biology Section Laboratory of Algal BiologyCenter of Advanced Study in BotanyBanaras Hindu UniversityVaranasi 221005India Department of Biotechnology Guru Ghasidas VishwavidyalayaBilaspur 495009India

Low availability of phosphorus(P) is a major constraint for optimal crop production, as P is mostly present in its insoluble form in soil. Therefore,phosphate-solubilizing bacteria(PSB) from paddy field soils of the Indo-Gangetic Plain, India were isolated, and their abundance was attempted to be correlated with the physicochemical characteristics of the soils. Ninety-four PSB were isolated on Pikovskaya’s agar medium, and quantitative phosphate solubilization was evaluated using NBRIP medium. The isolates solubilized P up to a concentration of 1 006 μg mL-1 from tricalcium phosphate with the secretion of organic acids. These isolates were identified by 16 S rRNA gene sequence comparison, and they belonged to Gammaproteobacteria(56 isolates),Firmicutes(28 isolates), Actinobacteria(8 isolates), and Alphaproteobacteria(2 isolates). Phylogenetic analysis confirmed the identification by clustering the isolates in the clade of the respective reference organisms. The correlation analysis between PSB abundance and physicochemical characteristics revealed that the PSB population increased with increasing levels of soil organic carbon, insoluble P, K+, and Mg2+. The promising PSB explored in this study can be further evaluated for their biofertilizer potential in the field and for their use as potent bio-inoculants.

关键词： bacterial abundance insoluble P organic acids phosphate solubilization phylogenetic analysis 16S rRNA gene

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Chemical and physical studies of metallic alloy-based old Indian coins with LIBS coupled with multivariate analysis

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Plasma Science and Technology 2023年第9期25卷 91-103页

作者： Vikas GUPTA Abhishekh Kumar rai Tejmani KUMAR Rajendhar JUNJURI G Manoj KUMAR A K rai Laser Spectroscopy Research Laboratory Department of PhysicsUniversity of AllahabadPrayagraj 211002India Department of Earth and Planetary Sciences University of AllahabadPrayagraj 211002India Advanced Centre of Research in High Energy Materials University of HyderabadHyderabad 500046 India Leibniz Institute of Photonic Technology Jena D-07745Germany

The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various *** old Indian coins in different years of circulation,(1922–1986)were selected for the *** concentrations were determined by Calibration free LIBS(CF-LIBS)*** concentration of cuprum(Cu)is negligible,and aluminum(Al)is maximum in the first five coins,and vice-versa in the remaining eight *** different multivariate methods,Principal Component Analysis(PCA)and Soft Independent Modelling of Class Analogy(SIMCA)have been used to classify and identify the *** classified all thirteen samples into four main alloy *** discernment of unknown samples to their probable class membership of alloy was performed using *** surface hardness(Brinell hardness number)is linearly correlated with the plasma temperature and LIBS intensity *** sample surface of the first and fifth coin belongs to Al-alloy,having the least surface hardness,and it became harder for Cu–Ni alloy,Ni-brass alloy,and bronze *** hardness of the surface is more for bronze sample *** is also observed that the plasma temperature increases monotonically with the Brinell hardness *** analysis provides valuable information on fabrication methodology and explains large diversification in the elementary composition of old coins.

关键词： LIBS metallic alloy stoichiometric ablation PCA SIMCA old indian coins surface hardness

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Spectroscopic investigation of light strange S=−1Λ and Σ and S=−2Ξbaryons

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Chinese Physics C 2021年第6期45卷 91-108页

作者： Chandni Menapara Ajay Kumar rai Department of Physics Sardar Vallabhbhai National Institute of TechnologySurat-395007GujaratIndia

The present study is dedicated to light-strange∧with strangeness S=−1 and isospin I=0,with S=−1 and I=1,andΞbaryon with S=−2 andI=1/*** this study,the hypercentral constituent quark model with linear confining potential has been employed along with a first order correction term to obtain the resonance masses up to approximately 4 *** calculated states include 1S-5S,1P-4P,1D-3D,1F-2F,and 1G(in a few cases)along with all possible spin-parity *** trajectories have been explored for the linearity of the calculated masses for(n,M^(2))and(J,M^(2)).Magnetic moments have been intensively studied for ground state spin 1/2 and,3/2 in addition to the configuration mixing of the first negative parity state ***,the transition magnetic moments and radiative decay widths have been presented.

关键词： mass spectra strange baryon Regge trajectory magnetic moment

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Spectroscopic study of strangeness=-3Ω^(-)baryon

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Chinese Physics C 2022年第10期46卷 43-51页

作者： Chandni Menapara Ajay Kumar rai Department of Physics Sardar Vallabhbhai National Institute of TechnologySurat-395007GujaratIndia

Ω^(-)baryon with sss quarks has been investigated through many theoretical studies so far but scarcely observed in ***,an attempt has been made to explore properties of Ω with hypercentral Constituent Quark Model(hCQM)with a linear confining *** resonance mass spectra have been obtained for 1S-4S,1P-4P,1D-3D,and *** Regge trajectory has been investigated for the linear nature based on calculated data along with the magnetic *** present work has been compared with various approaches and known experimental findings.

关键词： mass spectra strange baryon Regge trajectory magnetic moment

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Frequency dependence in the emission from subpulse drifting pulsars

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Research in Astronomy and Astrophysics 2021年第9期21卷 153-162页

作者： Xiao-Hong Han rai Yuen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesUrumqi 830011China SIfA School of PhysicsUniversity of SydneySydneyNSW 2006Australia

We investigate relations in the emission properties as revealed by drifting subpulses detected at different observing frequencies based on the method that incorporates the rotating carousels in pulsar magnetospheres of multiple emission *** emission state is associated with particular emission properties as determined by the drifting subpulses at a particular frequency,and different emission states obtained at different frequencies reveal the variation of emission properties across the emission *** method allows the determination of the essential radio emission properties such as the relative emission height,subpulse number,charge density and the plasma flow relative to corotation in an emission region for a particular *** apply the method to seven pulsars that exhibit subpulse drifting along single drift-band at 326 MHz and 1429 *** results show that drifting subpulses observed at different frequencies correspond to particular emission states suggesting that the pulsar emission properties are frequency *** show that emission follows the frequency-to-radius mapping for pulsars with obliquity angle?30°regardless of the sign and magnitude of the *** pulsars with long rotation periods in our sample,the circulation time for the plasma to revolve once around the magnetosphere relative to corotation increases as the rotation period increases at both frequencies,but exhibits irregularity for pulsars with short rotation *** results suggest that evolution of the obliquity angles in subpulse drifting pulsars is from large to small,and the emission region tends to be’thicker’in younger pulsars.

关键词： radiation mechanisms:non-thermal pulsar:general

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Promising light converting BaMoO_4:Er^(3+)-Tm^(3+)-Yb^(3+) phosphors for display and optical temperature sensing

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Journal of Rare Earths 2018年第12期36卷 1256-1263页

作者： Abhishek Kumar Soni Vineet Kumar rai Chemistry Division Bhabha Atomic Research Centre Laser and Spectroscopy Laboratory Department of Applied Physics Indian Institute of Technology (Indian School of Mines)

Er-Tm3+-Ybtri-doped BaMoOphosphors were synthesized by co-precipitation technique and characterized by X-ray diffraction analysis, absorption study and field emission scanning electron microscopy analysis. Upconversion as well as downconversion luminescence studies were performed by using near infrared(980 nm) and ultraviolet(380 nm) excitations. Energy level diagram, pump power dependence and colour coordinate study were utilized to describe the multicolor upconversion emission properties. Under single 980 nm diode laser excitation the dual mode sensing behaviour is realized via Stark sublevels and thermally coupled energy levels of the Tm3+ and Erions in the prepared tri-doped phosphors. A comparative fluorescence intensity ratio analysis for integrated emission intensities arising from the Stark sublevels {~1 G4(a)) and ~1 G4(b))} and thermally coupled energy levels {~2 Hand 4 S3/2} of the Tm3+ and Er3+ ions, respectively was carried out in the prepared tri-doped BaMoOphosphors. The maximum sensitivity for thermally coupled energy levels of the Er3+ and Stark sublevels of the Tm3+ ion was reported. The developed phosphors could be useful in the display devices and optical thermo metric applications.

关键词： Phosphor Optical temperature sensing Stark sublevels Thermally coupled energy levels Rare earths

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The hemispheric asymmetry of solar activity during the last century and the solar dynamo

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 115-126页

作者： Ashish Goel Arnab rai Choudhuri Department of Physics Indian Institute of Technology Department of Physics Indian Institute of Science

We believe the Babcock-Leighton process of poloidal field generation to be the main source of irregularity in the solar cycle. The random nature of this process may make the poloidal field in one hemisphere stronger than that in the other hemisphere at the end of a cycle. We expect this to induce an asymmetry in the next sunspot cycle. We look for evidence of this in the observational data and then model it theoretically with our dynamo code. Since actual polar field measurements exist only from the 1970s, we use the polar faculae number data recorded by Sheeley （1991, 2008） as a proxy of the polar field and estimate the hemispheric asymmetry of the polar field in different solar minima during the major part of the twentieth century. This asymmetry is found to have a reasonable correlation with the asymmetry of the next cycle. We then run our dynamo code by feeding information about this asymmetry at the successive minima and compare the results with observational data. We find that the theoretically computed asymmetries of different cycles compare favorably with the observational data, with the correlation coefficient being 0.73. Due to the coupling between the two hemispheres, any hemispheric asymmetry tends to get attenuated with time. The hemispheric asymmetry of a cycle either from observational data or from theoretical calculations statistically tends to be less than the asymmetry in the polar field （as inferred from the faculae data） in the preceding minimum. This reduction factor turns out to be 0.43 and 0.51 respectively in observational data and theoretical simulations.

关键词： Sun activity -- Sun magnetic fields -- sunspots

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