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structural,magnetic,and acidic properties of cobalt ferrite nanoparticles synthesised by wet chemical methods

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Journal of Advanced Ceramics 2015年第3期4卷 199-205页

作者： Manju KURIAN smitha THANKACHAN Divya s.nair Aswathy E.K. Aswathy bAbU Arathy THoMAs binu KRIsHNA K.T. Department of Chemistry Mar Athanasius CollegeKothamangalam-686666India Department of Physics Mar Athanasius CollegeKothamangalam-686666India

A detailed investigation on the effect of preparation method on the structural,magnetic,and acidic properties of cobalt ferrite nanoparticles prepared by sol-gel and co-precipitation is *** acid and ethylene glycol were used as gelling agents,while sodium hydroxide and aqueous ammonia were used as precipitating *** resulting ferrites were calcined at 450℃ and 750℃.sharper X-ray diffraction(XRD)peaks were observed for the samples calcined at 750℃,indicating greater crystallinity of the samples calcined at higher *** crystallite sizes fell in the ranges of 7.1-21.1 nm and 30.4-42.1 nm for the samples calcined at 450℃ and 750℃,*** infrared spectra revealed two main absorption bands,the high frequency bandν1 around 600 cm^(-1) and the low frequency bandν2 around 400 cm^(-1) arising from stretching vibrations of the oxygen bond with the metal in the tetrahedral(A)and octahedral(b)sites in the spinel *** of particles was observed in the scanning electron microscopy(sEM)*** parameters of CoFe_(2)o_(4) nanoparticles greatly depended on calcination temperature and preparation *** temperature programmed desorption(TPD)measurements indicated that weak acid sites predominate medium strength sites,while the number of strong acid sites is the *** acidity decreased for the samples calcined at higher *** results underline the effect of preparation conditions on the morphology,crystallite size,and magnetic properties of nano ferrites.

关键词： nano ferrites sol-gel technique co-precipitation magnetic property surface acidity

stock Prediction based on Technical Indicators Using Deep Learning Model

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Computers, Materials & Continua 2022年第1期70卷 287-304页

作者： Manish Agrawal Piyush Kumar shukla Rajit nair Anand Nayyar Mehedi Masud Department of Computer science&Engineering University Institute of TechnologyRajiv Gandhi Proudyogiki VishwavidyalayaBhopal-462033Madhya PradeshIndia Faculty of Department of Computer science&Engineering University Institute of TechnologyRajiv Gandhi Proudyogiki VishwavidyalayaBhopal-462033Madhya PradeshIndia Faculty of Department of Computer science&Engineering School of Engineering and TechnologyJagran Lakecity UniversityBhopal462026Madhya PradeshIndia Graduate school Duy Tan UniversityDa Nang550000Vietnam Faculty of Information Technology Duy Tan UniversityDa Nang550000Vietnam Department of Computer science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia

stock market trends forecast is one of the most current topics and a significant research challenge due to its dynamic and unstable *** stock data is usually non-stationary,and attributes are non-correlative to each *** traditional stock Technical Indicators(sTIs)may incorrectly predict the stockmarket *** study the stock market characteristics using sTIs and make efficient trading decisions,a robust model is *** paper aims to build up an Evolutionary Deep Learning Model(EDLM)to identify stock trends’prices by using *** proposed model has implemented the Deep Learning(DL)model to establish the concept of *** analysis of the dataset of three most popular banking organizations obtained from the live stock market based on the National stock exchange(NsE)-India,a Long short Term Memory(LsTM)is *** datasets encompassed the trading days from the 17^(th) of Nov 2008 to the 15^(th) of Nov *** work also conducted exhaustive experiments to study the correlation of various sTIs with stock price *** model built with an EDLM has shown significant improvements over two benchmark ML models and a deep learning *** proposed model aids investors in making profitable investment decisions as it presents trend-based forecasting and has achieved a prediction accuracy of 63.59%,56.25%,and 57.95%on the datasets of HDFC,Yes bank,and sbI,*** indicate that the proposed EDLA with a combination of sTIs can often provide improved results than the other state-of-the-art algorithms.

关键词： Long short term memory evolutionary deep learning model national stock exchange stock technical indicators predictive modelling prediction accuracy

Computational study on flow through truncated conical plug nozzle with base bleed

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Propulsion and Power Research 2019年第2期8卷 108-120页

作者： Prasanth P.nair Abhilash suryan Heuy Dong Kim Department of Mechanical Engineering College of Engineering TrivandrumTrivandrum 695016India Department of Mechanical Engineering Andong National UniversityAndong 760749Republic of Korea

Conical plug nozzle and truncated conical plug nozzle are advanced rocket nozzles suitable for use as altitude compensating *** this study flow through the conical plug and truncated conical plug nozzles are numerically simulated to first validate with experimental data and then to compare the performance when a base bleed is *** numerical analysis has considered two-dimensional axisymmetric ***-averaged Navierstokes equations are solved with two equation shear stress transport k-ω turbulence *** the validation of the plug nozzle,flow features and wall pressure along the length of the nozzle is taken for different nozzle pressure *** the validation of truncated plug nozzle,flow features and base pressures at various nozzle pressure ratios are *** base bleed is taken as 2%of the inlet mass flow *** comparison of results shows that the introduction of base bleed helps to compensate for the loss of thrust due to conical plug nozzle truncation.

关键词： Plug nozzle Aerospike nozzle Advanced rocket nozzle Reynolds-averaged Navier-stokes(RANs) base pressure Coefficient of thrust base bleed secondary flow

basement tectonics and flexural subsidence along western continental margin of India

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Geoscience Frontiers 2017年第5期8卷 1009-1024页

作者： D.K.Pandey Nisha nair Anju Pandey G. sriram Esso-National Centre for Antarctic and ocean Research Goa India

The Paleocene-recent post-rift subsidence history recorded in the Mumbai offshore basin off western continental margin of India is examined. Results obtained through 2-D flexural backstripping modelling of new seismic data reveal considerable thermo-tectonic subsidence over last ca. 56 Myr. Reverse postrift subsidence modelling with variable β stretching factor predicts residual topography of ca. 2000 m to the west of shelf Margin basin and fails to restore late Paleocene horizon and the underlying igneous basement to the sea level. This potentially implies that:(1) either the igneous basement formed during the late Cretaceous was emplaced under open marine environs; or(2) a laterally varying cumulative subsidence occurred within Mumbai offshore basin(Mob) during ca. 68 to ca. 56 Ma. Pre-depositional topographic variations at ca. 56 Ma across the basin could be attributed to the extensional processes such as varied lower crustal underplating along Western Continental Margin of India(WCMI). Investigations about basement tectonics after unroofing of sediments since late Paleocene from this region support a transitional and heavily stretched nature of crust with high to very high β factors. Computations of past sediment accumulation rates show that the basin sedimentation peaked during late Miocene concurrently with uplift of Himalayan-Tibetan Plateau and intensification of Indian monsoon system. Results from basin subsidence modelling presented here may have significant implications for further studies attempting to explore tectono-climatic interactions in Asia.

关键词： Continental rifting subsidence Mumbai offshore basin backstripping Arabian sea Laxmi basin

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optical parameters induced by phase transformation in RF magnetron sputtered Tio2 nanostructured thin films

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Progress in Natural science:Materials International 2014年第3期24卷 218-225页

作者： Prabitha b.nair V.b.Justinvictor Georgi P.Daniel K.Joy K.C.James Raju David Devraj Kumar P.V.Thomas Thin Film Lab Post Graduate and Research Department of Physics Mar Ivanios College school of Physics University of Hyderabad Central University P. O. College of Education Florida Atlantic University

Pure Tio2 thin films were deposited onto quartz substrates using a ceramic Tio2 target at an elevated substrate temperature of 573 K by RF magnetron sputtering, and an analysis of structural, optical and photoluminescence characteristics of the films upon phase transformation is reported in this paper. structural investigations using X-ray diffraction revealed that the as-deposited film was amorphous in nature. Thermal annealing for 2 h at 873 K in air resulted in the formation of anatase phase, and a phase transformation to rutile was observed at 1073 *** increase in grain size and an improvement in crystallinity were also observed on annealing. Rod- like rutile crystallites were observed in the sEM images of the film annealed at 1273 K. As-deposited films and films annealed up to 1073 K were highly transparent in the visible region with a transparency 480%. optical band gap of the films decreased upon thermal annealing which is attributed to phase transformation from amorphous to anatase and then to rutile. optical parameters such as refractive index, optical conductivity and optical dielectric constant increased with increase in annealing temperature. since rutile is the optically active phase, the superior refractive index of the film annealed at 1073 K along with its high transparency in visible region suggests the application of this film in antireflective coatings. Photoluminescence emission of maximum intensity was observed for the film annealed at 873 K, which exhibits anatase phase. Intense blue emission observed in this film makes it suitable for use in optoelectronic display devices.

关键词： RF magnetron sputtering Tio2thin films Dislocation density optical conductivity Photoluminescence

Improving the photocatalytic performance of Tio2 via hybridizing with graphene

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Journal of semiconductors 2017年第6期38卷 24-31页

作者： K s Divya Athulya K Madhu T U Umadevi T suprabha P.Radhakrishnan nair suresh Mathew school of Chemical sciences Mahatma Gandhi University Kottayam 686 560 Kerala India Advanced Molecular Materials Research Centre Mahatma Gandhi University Kottayam 686 560 Kerala India

In this paper an improvement in the photocatalytic performance of Tio2 was carried out via hybridizing with ***-Tio2（GR-Tio2/nanocomposites with different weight addition ratios of graphene oxide（Go）have been prepared via a facile microwave irradiation of Go and tetrabutyl titanate in isopropyl *** spectroscopy（Rs）,X-ray diffraction（XRD）,scanning electron microscopy（sEM）,transmission electron microscopy（TEM）,UV–visible spectroscopy（UV–vis）,Fourier transform infrared spectra（FTIR）,energy dispersive X-ray spectroscopy（EDX）and photoluminescence spectra（PL）are employed to determine the properties of the *** irradiation can heat the reactant to a higher temperature in a short time,simultaneously Go is reduced to graphene and Tio2 nanoparticles grown on the surface of ***-Tio2 nanocomposites synthesized via this approach have efficient electron conductivity in GR,resulting in a reduced electron–hole recombination *** the synthesized nanocomposites,GT-8wt% exhibited the best photocatalytic activity toward photocatalytic degradation of *** current work provides a new insight for the fabrication of GR-Tio2 nanocomposites within a short reaction time and also explains the mechanism of photocatalysis employing radical and hole scavengers.

关键词： graphene (GR) tetrabutyl titanate (TbT) GR-Tio2 nanocomposites methylene blue photocatalysis

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Algorithm-improved high-speed and non-invasive confocal Raman imaging of 2D materials

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National science Review 2020年第3期7卷 620-628页

作者： sachin nair Jun Gao Qirong Yao Michael H.G.Duits Cees otto Frieder Mugele Physics of Complex Fluids MESA+Institute for NanotechnologyUniversity of Twente Physics of Interfaces and Nanomaterials MESA+ Institute for NanotechnologyUniversity of Twente Medical Cell bio Physics Tech Med Centre University of Twente

Confocal Raman microscopy is important for characterizing 2 D materials, but its low throughput significantly hinders its applications. For metastable materials such as graphene oxide(Go), the low throughput is aggravated by the requirement of extremely low laser dose to avoid sample damage. Here we introduce algorithm-improved confocal Raman microscopy(ai-CRM), which increases the Raman scanning rate by one to two orders of magnitude with respect to state-of-the-art works for a variety of 2 D materials. Meanwhile, Go can be imaged at a laser dose that is two to three orders of magnitude lower than previously reported, such that laser-induced variations of the material properties can be avoided. ai-CRM also enables fast and spatially resolved quantitative analysis, and is readily extended to 3 D mapping of composite materials. since ai-CRM is based on general mathematical principles, it is cost-effective, facile to implement and universally applicable to other hyperspectral imaging methods.

关键词： 2D materials graphene graphene oxide confocal Raman microscopy algorithm

Wage Implication of Trade Liberalization in bolivia

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Wage Implication of Trade Liberalization in Bolivia

作者： Neila nair soliz Perez 浙江工商大学

学位级别：硕士

The purpose of this paper is to research about the relationship between wage and trade after the liberalization in the country of *** are many theories and economist explain how this trade will influence wage in Latin *** variables in order to use in this paper will be the trade balance,unemployment rate,the index of education of bolivia and a variable of the industry the Foreign Direct *** is a brief introduction about some facts and literature review of that influence of the ***,there is a part of theorical research about the effect of trade on wage in the short and long ***,the need to have stylized facts is essential in order to mix with the theory,that is the reason to mention information about trade and the change of wage in ***,the use of empirical results is convenient for the purpose of prove the relationship between the variables *** one is made by the program of stata and with specific data from official websites.

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spontaneous distal ureteric rupture: A rare case report and review of literature

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Asian Journal of Urology 2020年第1期7卷 61-63页

作者： Li sian Low shiva Madhwan nair Urology Department Waikato HospitalHamiltonWaikatoNew Zealand

spontaneous rupture of the ureter is a very interesting and unusual phenomenon which normally occurs due to ureteral *** present a case of spontaneous rupture of the distal ureter,secondary to a ureteric *** patient p... 详细信息

关键词： spontaneous Distal ureteric calculi Ureteric rupture