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Progress in Natural Science:Materials International 2019年第4期29卷 457-465页

作者： Suman Sheoran Vachan singh Sitender singh Sonika Kadyan Jasbir singh Devender singh Department of Chemistry Maharshi Dayanand University Department of Physics Government College

Down-conversion properties of Eu3+doped M2Y2Si2O9(M=Ba,Ca,Mg,Sr) phosphors have been investigated in *** phosphors were synthesized via the simple,fast and cost-effective sol-gel technique at a temperature of 950℃.Color coordinates and emission color can be altered by the varying concentration of dopant ion in *** luminescence intensity was obtained when doping 0.03 mol of Eu3+*** the excitation wavelength of 395 nm,these silicates showed strong red color,pure and sharp spectral peaks in visible region due to ~5 D0→F1-3transitions of Eu3+present in the *** of reaction temperature on luminescence was also analyzed for these *** sharp peaks in the X-ray diffraction pattern indicated the high crystallinity of prepared ***2Y2Si2O9has shown an orthorhombic crystal *** FTIR results confirmed the metal-oxygen vibrational modes available in the range of 400-1600 *** electron microscopy images have revealed that the variation of alkaline earth metal provided a very different crystal *** down conversion response of these phosphor materials can provide a great significance in the application of the coming solar devices.

关键词： M2Y2Si2O9:Eu3+ Phosphor Sol-gel Lattice Solar devices

Linear Recurring Sequences and Explicit Factors of x2nd—1 in Fq[x]

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Algebra Colloquium 2020年第3期27卷 563-574页

作者： Manjit singh Deenbandhu Chhotu Ram University of Science and Technology Murthal 131039 India

Let F_(q) be a finite field of odd characteristic containing q elements,and n be a positive *** important problem in finite field theory is to factorize x^(n)-1 into the product of irreducible factors over a finite *** the realm of theoretical needs,the availability of coefficients of irreducible factors over finite fields is also very important for *** this paper,we introduce second order linear recurring sequences in F_(q) and reformulate the explicit factorization of x^(2nd)-1 over in such a way that the coefficients of its irreducible factors can be determined from these sequences when d is an odd divisor of q+1.

关键词： linear recurring sequences factorization finite fields cyclotomic factors

Studies on selected polymeric materials using the photoacoustic spectroscopic technique

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Chinese Physics B 2011年第6期20卷 453-457页

作者： Hukum singh School of Engineering and Technology ITM University

Polymethylmethacrylat-graft-polybisphenol A-carbonate （PMMA-G-PC） with 50% grafting is synthesized. The graft co-polymerization of methyhnethacrylate （0.036 mol. lit-1） onto polybisphenol-A-carbonate （0.5 g） in the presence of a redox couple formed from potassium persulphate （40 mol-lit-1） and thio-urea （30 mmol. lit-1） in aqueous nitric acid （0.18 M, 100 ml） in air at （45±2）℃ for 3.0 h. Condensation of （PMMA-G-PC） with N- [p-（carboxyl phenyl amino acetic acid）] hydrazide （PCPH） affords polybisphenol-A-carbonate-graft-polymethylmethacrylate hydrazide （PCGH）. The photoacoustic （PA） spectra of （PCGH） are recorded in a wavelength range from 200 nm to 800 nm at a modulation frequency of 22 Hz, and compared with those of pure polybisphenol-A-carbonate （PC）, （PMMA-G-PC） and （PCPH）. In the present work, a non-destructive and non-contact analytical method, namely the photoacoustic technique, is successfully implemented for optical and thermal characterization of selected polymeric materials. The indigenous PA spectrometer used in the present study consists of a 300-W xenon arc lamp, a lock-in amplifier, a chopper, a （1/8）-m monochromator controlled by computer and a home-made PA cell.

关键词： photoacoustic PCPH PCGH PMMA

Performance evaluation of nanofluid-based minimum quantity lubrication grinding of Ni-Cr alloy under the influence of CuO nanoparticles

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Advances in Manufacturing 2021年第4期9卷 580-591页

作者： Roshan Lal Virdi Sukhpal singh Chatha Hazoor singh Department of Mechanical Engineering Punjabi UniversityPatialaIndia Yadavindra College of Engineering Guru Kashi Punjabi University CampusTalwandi SaboIndia

In machining processes,researchers are actively engaged in exploring minimum quantity lubrication(MQL)as a possible alternative to traditional flood cooling owing to economic and ecological *** search for ecologically safe lubricants has attracted the attention of scientists looking to use vegetable oil as a *** nanofluid MQL technique with biodegradable oils as the base is a relatively new method with the potential to replace mineral *** the present study,the grinding of Inconel-718 alloy was investigated using nanofluid MQL(NFMQL)with biodegradable oils as the *** are composed by dispersing 0.5%(mass fraction)and 1%(mass fraction)of CuO nanoparticles in vegetable *** surface morphology,G-ratio,forces,and grinding energy were examined under pure MQL,NFMQL,and dry and flood lubrication *** experimental results indicated that the nanofluid MQL significantly improved the machining *** to the polishing and rolling effect of nanoparticles on the tool work interface,a surface finish under a 0.5%(mass fraction)nanofluid was found to be better than pure MQL-dry and flood lubrication *** NFMQL technique with 1%(mass fraction)CuO nanoparticles with palm oil as the base helped in achieving a better evacuation of chips from the grinding zone,leading to a better surface finish with a high material removal rate along with less energy consumption compared to flood and dry grinding.

关键词： Minimum quantity lubrication(MQL) Nanoparticles Grinding Vegetable oils Inconel-718 alloy

Radiating two-fluid universe coupled with rotation interacting with a scalar field

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Research in Astronomy and Astrophysics 2011年第3期11卷 271-285页

作者： Koijam Manihar singh Kangujam Priyokumar singh Thiyam Jairam singh Department of Mathematics Sambalpur University Department of Mathematics Ideal Girls College Department of Mathematics Manipur University

The solution of three new interesting studies,a rotating anisotropic twofluid universe coupled with radiation and a scalar field,are studied here,where the anisotropic pressure is generated by the presence of two non-interacting perfect fluids which are in relative motion with respect to each *** this problem,special discussion is made of the physically interesting class of models in which one fluid is a perfect comoving radiative fluid which is taken to model the cosmic microwave background and the second a perfect non-comoving fluid which will model the observed material content of the *** the different aspects of these model universes,the role of the radiation and scalar fields in defining the physical and dynamical properties of these models is specifically *** of the rotational perturbations is also made,in the course of which the amount of anisotropy induced in the pressure distribution by a small deviation from the Friedmann metric is also investigated,and it is observed that such anisotropies could grow faster than the expansion of the universe. All the models obtained in this problem are found to be theoretically satisfactory and thereby substantiate the possibilities of the existence of such astrophysical objects in this universe.

关键词： cosmic microwave background—cosmology:miscellaneous—stars:formation

Effects of Green Manures and Zinc Fertilizer Sources on DTPA-Extractable Zinc in Soil and Zinc Content in Basmati Rice Plants at Different Growth Stages

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Pedosphere 2019年第4期29卷 504-515页

作者： Amarpreet singh Yashbir singh SHIVAY Division of Agronomy ICAR-Indian Agricultural Research Institute (IARI) New Delhi 110012 (India) Division of Crop Production ICAR- Central Research Institute for Jute and Allied Fibres Barrackpore Kolkata West Bengal 700120 (India)

Rice is very sensitive to low zinc(Zn) supply in submerged paddy soils and Zn deficiency is one of the major limiting factors in determining rice production in India. A field experiment was conducted during the summer-rainy seasons of 2009 and 2010 at the research farm of the Indian Agricultural Research Institute, New Delhi, to determine the effects of summer green manure crops and Zn fertilizers on diethylenetriaminepentaacetic acid(DTPA)-extractable(available) Zn concentration in soil and total Zn content in Basmati rice cultivar Pusa Basmati 1 at periodic intervals. Summer green manure crops included Sesbania aculeata(Dhaincha),Crotalaria juncea(Sunhemp), and Vigna unguiculata(Cowpea) and the Zn fertilizers used were ethylenediaminetetraacetic acid(EDTA)-chelated Zn, ZnSO4·7H2O, ZnSO4·H2O, ZnO, and ZnSO4·7H2O + ZnO. Beneficial effects of summer green manure crops and Zn fertilizers on DTPA-extractable Zn concentration in soil and total Zn content in dry matter of Basmati rice at periodic intervals were observed, with significant increases in all the determined parameters, in comparison with those in the control(no Zn application or summer fallow). The rate of increase varied among summer green manure crops and Zn fertilizers during both years. Among the summer green manures, incorporation of S. aculeata led to a significant increase in mean Zn content in Basmati rice grain and straw when compared with C. juncea, V. unguiculata, and summer fallow treatments. Among the Zn fertilizers, significant increases in Zn content in Basmati rice dry matter and DTPA-extractable Zn concentration in soil during various growth stages of the plant were recorded with EDTA-chelated Zn application, followed by the application of ZnSO4·7H2O, ZnSO4·H2O, ZnSO4·7H2O + ZnO, ZnO,and no Zn. The highest mean Zn content in Basmati rice grain and straw was recorded with EDTA-chelated Zn application in 2009 and 2010, respectively. The application of ZnSO4·7H2O was the second best treatment af

关键词： available Zn fertilizer application plant zinc uptake rice production soil fertility summer green manure zinc deficiency zinc source zinc supply

Maxwell's equal area law for Vaidya-Bonner-de Sitter black hole under Lorentz invariance violation

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Chinese Physics C 2024年第11期48卷 231-246页

作者： Yenshembam Priyobarta singh Telem Ibungochouba singh Sapam Niranjan singh Department of Mathematics Manipur UniversityCanchipurImphal 795003ManipurIndia

In this study,we investigate the tunneling of fermions with arbitrary spin near the event horizon of a nonstationary Vaidya-Bonner-de Sitter(VBdS)black hole under Lorentz invariance violation(LIV).The modified Hawking temperature of VBdS black holes is calculated by using tortoise coordinate transformation,Feynman prescription,and Wentzel-Kramers-Brillouin *** considering the cosmological constant as a thermodynamic pressure in the extended phase space,we construct a Maxwell's equal area law under LIV and study the phase transitions of VBdS black hole in P-v,P-V,and T-S *** LIV increases the length of the liquid-gas coexistence *** thermodynamic quantities such as the entropy,heat capacity,Helmholtz free energy,internal energy,enthalpy,and Gibbs free energy of the VBdS black hole are *** quantities tend to increase under *** stability of the black hole is also discussed in the presence of LIV.

关键词： Hawking temperature Lorentz invariance violation Maxwell's equal area law Entropy

Assessing the bioremediation potential of arsenic tolerant bacterial strains in rice rhizosphere interface

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Journal of Environmental Sciences 2016年第10期28卷 112-119页

作者： Namrata singh Shubhi Srivastava Sushma Rathaur Nandita singh Eco-auditing Group CSIR-National Botanical Research Institute Lucknow 226001 India Department of Biochemistry Banaras Hindu University Varanasi 221001 India

The arsenic tolerant bacterial strains Staphylococcus arlettae （NBRIEAG-6）, Staphylococcus sp. （NBRIEAG-8） and Brevibadllus sp. （NBRIEAG-9） were tested for their roles in enhancing plant growth and induction of stress-related enzymes in rice （Oryza sativa L. cv. NDR-3Bg） plants at two different concentrations, 30 and IS mg/kg of As（V） and As（Ⅲ）, respectively. An experiment was conducted to test the effect of these strains on plant growth promotion and arsenic uptake. We found 30%-40% reduction in total As uptake in bacteria-inoculated plants, with increased plant growth parameters compared to non-inoculated plants. Moreover, the bacteria-inoculated plants showed reduced activity of total glutathione （GSH） and glutathione reductase （GR） compared to their respective controls, which suggests the bacteria-mediated reduction of oxidative stress in plants. Thus, these strains were found to be beneficial in terms of the biochemical and physiological status of the plants under arsenic stress conditions. Furthermore, one-way ANOVA and principal component analysis （PCA） on enzymatic and non-enzymatic assays also revealed clear variations. The results support the distinction between control and treatments in both shoots and roots. Therefore, this study demonstrates the potential of rhizobacteria in alleviating arsenic stress in rice plants.

关键词： Antioxidative enzymeOryza satiua L.Environmental contaminationMetalsSoil bacteria

Rayleigh-type wave propagation in incompressible visco-elastic media under initial stress

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Applied Mathematics and Mechanics(English Edition) 2018年第3期39卷 317-334页

作者： P.singh A.CHATTOPADHYAY A.K.singh Department of Applied Mathematics Indian Institute of Technology (ISM)

Propagation of Rayleigh-type surface waves in an incompressible visco-elastic material over incompressible visco-elastic semi-infinite media under the effect of initial stresses is discussed. The dispersion equation is determined to study the effect of differ- ent types of parameters such as inhomogeneity, initial stress, wave number, phase velocity, damping factor, visco-elasticity, and incompressibility on the Rayleigh-type wave prop- agation. It is found that the affecting parameters have a significant effect on the wave propagation. Cardano＇s and Ferrari＇s methods are deployed to estimate the roots of dif- ferential equations associated with layer and semi-infinite media. The MATHEMATICA software is applied to explicate the effect of these parameters graphically.

关键词： Rayleigh-type wave inhomogeneity initial stress visco-elasticity incom-pressible

Microplastics in soil: Impacts and microbial diversity and degradation

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Pedosphere 2022年第1期32卷 49-60页

作者： Paramdeep KAUR Kashmir singh Baljinder singh Department of Biotechnology Panjab UniversityChandigarh 160014India

Microplastics(MPs) are plastic particles less than 5 mm in size that have become a major environmental pollutant due to their ubiquitous and persistent nature. Microplastic contamination of the aquatic environment has received the most attention so far, whereas the current understanding of MP prevalence and its impacts in the terrestrial environment is largely limited. The MP contamination of soil can cause bioaccumulation and toxicity in terrestrial animals and plants, which can consequently affect human health. This review is aimed towards combining the available information on the occurrence, sources, and effects of MPs on the different aspects of the terrestrial environment and to highlight the limitations in our knowledge regarding the nature and impacts of MPs in soil. The review also highlights microbial degradation of MPs as an advancing research area, with numerous microorganisms being identified as capable of efficiently degrading this persistent contaminant.

关键词： bioaccumulation biodegradation environmental pollutants microplastic contamination persistent contaminate terrestrial environment