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Relativistic Variation of black Hole Temperature with Respect to Velocity in XRbs and AGN

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International Journal of Astronomy and Astrophysics 2017年第1期7卷 1-10页

作者： Dipo mahto Alok Ranjan Krishna Murari Singh Department of physics Marwari College T. M. B. University Bhagalpur India Department of physics T. M. B. University Bhagalpur India

Stephen Hawking gave a formula for the temperature of black holes as given by . Some of the black holes have their spinning velocity from 50% to 99% of the velocity of light. Due to this velocity, the mass of black holes will vary which cause the variation in the temperature of black holes. In the present research article, we have applied the variation of mass with velocity to obtain the rate of change in temperature of the black holes with respect to velocity. We have also calculated their values for super dense stars like black holes existing in XRbs and AGN and concluded that for super dense stars like black holes of lower velocity as well as the velocity comparable to the velocity of light, the rate of change in temperature with respect to velocity is directly proportional to their velocities. This work will help us to find out the variation in temperature of different black holes spinning with different velocity percentage related to light speed and can be used as the references for other research works.

关键词： Hawking Temperature black Holes XRbs AGN

Effect of Thickness of SnO_2:F over Layer on Certain physical properties of ZnO:Al Thin Films for Opto-electronic Applications

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Journal of Materials Science & Technology 2012年第11期28卷 999-1003页

作者： p. Ravikumar K. Ravichandran b. Sakthivel p.G and Research Department of physics AVVM Sri Pushpam College (Autonomous)

bilayered FTO/AZO （fluorine doped tin oxide/aluminium doped zinc oxide） films were fabricated using a simple, cost effective spray pyrolysis technique. X-ray diffraction （XRD） profiles of bilayered films showed that in the case of lower thickness FTO over layers, （002） plane of ZnO phase had the highest intensity, whereas the predominance was changed in favour of （200） plane of SnO2 phase for higher thickness FTO over layer. UV studies showed that bilayered FTO/AZO films exhibited a sharp absorption edge as that of AZO film. The decrease in the photoluminescence （pL） peak at 420 nm with increasing FTO over layer thickness indicated a reduction in the zinc vacancies which caused a reduction in the sheet resistance （Rsh）. Electrical studies revealed that, eventhough the Rsh value （916Ω/□） of bilayered FTO （313 nm）/AZO （314 nm） film was found to be higher than that of FTO single layer film （72Ω/□）, it was much lower than that of AZO single layer film （5661Ω/□））. The atomic force microscopy （AFM） images reflect the characteristic features of both zinc oxide and tin oxide films.

关键词： ZnO thin films Sn02 Semiconductor materials Optical properties Electricalproperties Atomic force microscopy (AFM)

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A novel approach to correlate heat transfer and pressure fluctuation in gas-solid spouted bed

作者： (美)b.p.·齐格勒(b.p. Zeigler)

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particuology 2019年第1期17卷 26-34页

作者： p.K. Mollick p.S. Goswamib M. Krishnana p.K. Vijayanc A.b. panditd Mechanical Metallurgy Division Bhabha Atomic Research CentreMumbai 400085India Deptartmenr of Chemical Engineering Indian Institute ofTechnology-BombayMumbai 400076India Reactor Engineering Division Bhabha Atomic Research CentreMumbai 400085India Deptartment of Chemical Engineering Institute of Chemical TechnologyMumbai 400019India

Statistical analysis of pressure fluctuations in spouted beds has been used as a well-established diagnostic tool to determine bed and flow characteristics because of its smooth operation. However, in many recent and conventional applications of spouted beds such as drying, coal gasification, catalytic conversion, biomass treatment, and chemical vapor deposition, direct estimation of the heat transfer rate from the solid bed to the gas or vice versa has proven to be difficult. A variance and spectral analysis of pressure fluctuation is extended here to characterize the heat transfer phenomena in a spouted bed. In the present study, zirconia and alumina were used as the bed materials, and argon and nitrogen were used as the spouting gases. Experiments were conducted at various heating rates for different superficial gas velocities for a range of temperatures up to 300 °C. Significant changes in the gas density and viscosity with different extents of heat transfer were observed to affect the momentum diffusivity and gas–particle interaction, which in turn led to local pressure fluctuations, causing the bed to behave differently. In the present work, a novel approach is proposed to establish a link between local pressure fluctuation and the extent of heat transfer in the bed. This method shows potential for correlation of the statistics of pressure fluctuation with the thermal properties of individual solids and gases. Thus, the technique can be extended to many industrial applications for the indirect estimation of the extent of heat transfer and prediction of unknown thermal properties of products in solids or gases.

关键词： Spouted bed Heat transfer pressure fluctuation Statistical analysis power spectral density analysis Thermal properties

Influence of Annealing on physical properties of CdO Thin Films prepared by SILAR Method

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Journal of Materials Science & Technology 2013年第1期29卷 17-21页

作者： b.Gokul p.Matheswaran R.Sathyamoorthy pG and Research Department of physics Kongunadu Arts and Science College (Autonomous)

Cadmium oxide （CdO） thin films were prepared by successive ionic layer adsorption and reaction （SILAR） method and annealed at 250-450 ℃ for 2 h. The prepared films were characterized by X-ray diffraction （XRD）, optical spectroscopy, scanning electron microscopy （SEM） and Hall effect measurement. The XRD analysis reveals that the films were polycrystalline with cubic structure. both crystallinity and the grain size were found to increase with increasing annealing temperature. SEM analysis shows the porous nature of the surface with spherical nanoclusters. Energy dispersive spectroscopic analysis （EDS） confirmed the presence of Cd and O elements without any additional impurities. The films exhibited maximum transmittance （82%-86%） in infra-red （IR） region. Transmittance was found to decrease with increasing annealing temperature （Eg） was in the range of 2.24-2.44 eV. Hall effect measurement shows an and the estimated band gap energy ncrease in carrier concentration and a decrease in resistivity with increasing annealing temperature. The carrier concentration （N） and resistivity （p） of about 1.26 × 1022 cm-3 and 8.71 × 10 3 Ω cm are achieved for the film annealed at 450 ℃ for 2 h.

关键词： Annealing porous structure Hall effect Electrical resistivity

performance analysis of new word weighting procedures for opinion mining

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Frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1186-1198页

作者： G.R.bRINDHA p.SWAMINATHAN b.SANTHI School of Computing SASTRA University

The proliferation of forums and blogs leads to challenges and opportunities for processing large amounts of information. The information shared on various topics often contains opinionated words which are qualitative in nature. These qualitative words need statistical computations to convert them into useful quantitative data. This data should be processed properly since it expresses opinions. Each of these opinion bearing words differs based on the significant meaning it conveys. To process the linguistic meaning of words into data and to enhance opinion mining analysis, we propose a novel weighting scheme, referred to as inferred word weighting(IWW). IWW is computed based on the significance of the word in the document(SWD) and the significance of the word in the expression(SWE) to enhance their performance. The proposed weighting methods give an analytic view and provide appropriate weights to the words compared to existing methods. In addition to the new weighting methods, another type of checking is done on the performance of text classification by including stop-words. Generally, stop-words are removed in text processing. When this new concept of including stop-words is applied to the proposed and existing weighting methods, two facts are observed:(1) Classification performance is enhanced;(2) The outcome difference between inclusion and exclusion of stop-words is smaller in the proposed methods, and larger in existing methods. The inferences provided by these observations are discussed. Experimental results of the benchmark data sets show the potential enhancement in terms of classification accuracy.

关键词： Inferred word weight Opinion mining Supervised classification Support vector machine(SVM) Machine learning

A new thermodynamically stable Nb_(2)Ni intermetallic compound phase revealed by peritectoid transition within binary Nb-Ni alloy system

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Journal of Materials Science & Technology 2022年第5期100卷 246-253页

作者： J.F.Zhao H.p.Wang b.Wei School of physical Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

A new intermetallic compound of thermodynamically stable Nb_(2)Ni phase is discovered within Nb-Ni binary system,refreshing the current situation that there are only three stable intermediate phases of Nb_(7)Ni_(6),NbNi_(3) and NbNi_(8).The new stable phase is generated from the peritectoid transition:(Nb)+Nb_(7)Ni_(6)→Nb_(2)Ni,and the transformation temperature is 1533 *** refreshes the current equilibrium Nb-Ni binary phase *** is confirmed by transmission electron microscopy and the annealing experiments,which is determined to be the FCC structure(pearson:cF96,space grope:Fd-3m O2,a=11.888A).Furthermore,the equilibrium properties of Nb_(2)Ni phase are produced by density functional theory,including the formation energy,cohesive energy,bulk modulus and lattice constant.

关键词： Intermetallic compound peritectoid transition Transmission electron microscopy Density functional theory Nb alloy

Stochastic Energy Management of Microgrid with Nodal pricing

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Journal of Modern power Systems and Clean Energy 2020年第1期8卷 102-110页

作者： Dhanapala prudhviraj p.b.S.Kiran Naran M.pindoriya IEEE Department of Electrical Engineering Indian Institute of Technology GandhinagarPalaj 382355GandhinagarIndia

This paper develops a stochastic framework for the energy management of a microgrid to minimize the energy cost from the *** considers the uncertainties in solar photovoltaic(pV)generation,load demand,and electricity ***,the opportunity of flexible load demand,i.e.,the effect of demand response(DR),on the test system is *** uncertainties are modeled by using Monte Carlo simulations and the generated scenarios are reduced to improve the computational *** general,microgrid scheduling is implemented by using substation(source node)price as a reference,but that reference price is not the same at all ***,this paper develops the nodal price based energy management in a microgrid to improve the scheduling *** stochastic energy management framework is formulated as a mixed integer non-linear programming(MINLp).Four case studies are simulated for a modified 15-node radial distribution network integrated with solar pV and battery energy storage system(bESS)to validate the effectiveness of the energy management framework for a microgrid with nodal pricing.

关键词： battery energy storage system(bESS) demand response(DR) distributed generation microgrid mixed integer non-linear programming(MINLp) scheduling stochastic optimization

Antral exfoliative cytology for the detection of Helicobacter pylori in the stomach

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World Journal of Gastroenterology 2005年第18期11卷 2784-2788页

作者： Claudio A.R. Gomes Jr Wilson R. Catapani Ana M.A.A. Mader Angelo Locatelli Claudilene b.p. Silva Jaques Waisberg Department of Gastroenterology Surgery and pathology ABC Faculty of Medicine Avenida Príncipe de Gales 821 Santo André S■o Paulo Brazil

AIM: To evaluate the efficacy of antral exfoliative cytology method in the diagnosis of Helicobacter pylori (H pylori)infection in the ***: Fifty patients were submitted to upper digestivetract endoscopy due to complaints of dyspepsia. Thematerial for exfoliative cytology was obtained by extensive brushing of the gastric antral mucosa and papanicolaou stain was used to identify the bacteria. The authors also performed gastric biopsies to collect material for urease tests and histologic studies, with hematoxylin-eosin and fucsin stains in order to identify the microorganism. The gold standard used to detect the presence of H pylori was an analysis of the combined results from the gastric biopsies by urease test and histological method. RESULTS: Antral exfoliative cytology method exhibited 90.3% sensitivity, 66.6% specificity, accuracy of 81.6%, positive predictive value of 82.3% and negative predictive value of 80.0%, in this population with a prevalence of 63.3%.CONCLUSION: Antral exfoliative cytology was demonstrated to be a sensitive, accurate and easy to perform method for investigating H pylori infection in the stomach.

关键词： H pylori Exfoliative cytology Stomach