Investigation of optical and structural properties of scheelite-type barium tungstate ceramic

Abstract-The manuscript presents the optical and structural behaviour of Barium tungstate synthesized by solid state reaction route. The structuralcharacterization was studied via X-ray diffraction and microstructural analysis. The X-ray diffraction study reveals a scheelite phase with tetragonal symmetry. The optical behaviour was analysed by UV-visible spectroscopy and photoluminescence. The UV-visible shows an absorbance peak in the UV rangewith an optical band gap of 4.85eV. A broad peak around 433 nm is obtained from the photoluminescence study.

Keywords: A. Ceramics, B. X-ray diffraction, C. scheelite. D. photoluminescence study.Barium tungstate.

Review on Structural and Optical Properties of Rare Earth Modified Barium Tungstate Ceramic

Rare earth doped Barium Tungstate (BaWO4) materials were studied due to high special level structure and luminescence properties, and have been widely used in solid-state lasers, medical diagnosis infrared anti-counterfeiting and optical fiber communication. The selection of rare earth ions and matrix materialhas great influence on the up-conversion of the luminescence performance. This paper reviewed on the structural and optical properties of RE doped BaWO4(RE: Dysprosium(Dy), Erbium (Er), Samarium (Sm), Europium(Eu),Holmium(Ho), Praseodymium(Pr), Ytterbium(Yb) and processing method. In this review, the Judd–Ofelt intensity parameters, Ω2 and Ω4 were obtained from the fluorescence emission spectra. The hypersensitive nature of the transition is confirmed from the higher value of the Ω2. The lower symmetry of RE3+coordination environment and the covalent character of RE–O bond are also confirmed from the higher value of Ω2. By using the calculated J O intensity parameters, the variousradiative and laser parameters of the excited level are determined.

Structural and Electrical Properties of La doped BFO-STO based Solid Solutions

The polycrystalline sample of (1-x)[Bi(1-y)LayFeO3]-x[SrTiO3] (x=0.5, y=0.5) was prepared by using the conventional solid-state reaction technique and sintered at high temperature(11700C).Structural analysis of the materialwith room temperature X-ray diffraction data confirmed the formation of compound in the rhombohedral crystal system. The surface morphology recorded by scanning electron microscopy (SEM) reveals a polycrystalline nature of sample with uniform distribution of grains. The homogeneous mixing of the components was confirmed by energy dispersive spectroscopy of X-ray (EDAX). Dielectric and complex impedance spectroscopic studies were carried out in a wide frequency (i.e.102–106Hz) and temperature (30–4500C) range. Dielectric studies indicate a ferroelectric–paraelectric phase transition at 3250C in the material.Complex impedance spectra confirm the significant contribution of grain to electrical response of the material. With rise of temperature, the bulk resistance of the compound decreases like thatof a semiconductor, which shows a negative temperature coefficient of resistance (NTCR) behavior.The nature of frequency dependence of ac conductivity of the sample follows the Jonscher ’spower law, and calculated dc conductivity follows Arrhenius behavior.

Study of Fission Fragment Mass Distribution of 252Cf

Study of fission is very interesting and it has always its own place in the science. When a compoundnucleus under goes decay by fission the two heavy fragment called as the fission fragment moves in the opposite direction in the center of mass. A study has been done for the mass distribution of the 252Cf source and found that the mass distribution can be symmetric or asymmetric depend on the excitation energy.

Development of a Prototype for ion beam diagnostic

Simulation of an electrostatic mirror

A review for the neutron production using ion beam from accelerator

Study of Potential Surface for U+U to understand Ternary process

Ternary decay a review in nuclear reaction

Smart materials: Properties and Applications

Study of Energy Loss for Some Metal Foils (A Possible Source for Secondary Electron)

The secondary electron are very important for many devices like scanning electron microscope, tunneling microscope etc. Not only in material science but also it plays a very important role in the nuclear physics. Especially for the development of many experimental setup or triggering devices. In Present report a study has done for the emission of secondary electron using metal films and identified a possible candidate which can be used as potential source of a secondary electrons.

Effect of Entrance channel to the cross section

The cross section measurement is one of the important quantity in nuclear physics in fact in almost all the experiment people measured the cross section. According Bohr the formation of a compound nucleus is independent of entrance channel i.e. the formation and the decay of the compound nucleus is independent phenomena. But whether that is applicable to a loosely bound case where the projectile is a loosely bound nucleus. A calculation has been done using a loosely bound nuclei and compared with the Bohr compound nucleus hypothesis and found that for loosely bound nuclei the situation is different.

A review of Scintillators

In the present day when anyone visits a medical for checkup, doctors immediately refer him/her for diagnosis. Out of many diagnosis medical imaging like X-Ray, CT, PET and MRI are the important ones. In one line the quality of photograph is important which depends on the associated Scintillators including the electronics driver. In the present paper a reviews of properties of a Scintillators has been discussed.

Investigation of the Phase Formation Mechanism of SrBi2Ta2O9 Ferroelectric Ceramic Prepared through Mixed-oxide Route

Analysis of Frequency and Temperature Dependent Dielectric and Conductivity Study of SrBi2Ta2O9 Ceramic

Study of Various Rare Earth Doped SrBi2Ta2O9 Ceramic for Device

Investigations on structure, dielectric and ferroelectric properties of SrBi2Ta2O9 ceramic via A-site defect engineering

Investigation of Dielectric, Ferroelectric and Conduction Behavior of Dy3+ Substituted SrBi2 Ta2 O9 Bismuth Layer Structured Ceramics

The present manuscript explores the impact of Dy doping in the Tantalum based bismuth layer structured ferroelectrics with chemical composition of Sr(Bi1-xDyx)2Ta2O9 (where x = 0.00, 0.025, 0.05, 0.075 and 0.10) prepared by mixed oxide process. Xray diffraction study of all the ceramics implement orthorhombic phase without any secondary phase. The polycrystalline nature and grain distribution in the materials is studied from scanning electron microscope study. The temperature dependent dielectric performance of Dy doped SBT ceramics at selected frequencies indicates diffuse order phase transitions with reduction in transition temperature (Tc) and relative permittivity with doping level. The residual polarization and coercive field reduce with doping. The conduction mechanism was analyzed using the frequency and temperature domain impedance spectroscopy for all composition. The electrical contribution from both grains and grain boundary in the doped ceramics in the reported temperatures is confirmed from the Nyquist plots and the non-Debye type of relaxation mechanism is manifested from the depressed semicircles in all of them. The ac conductivities variation with frequencies at the studied temperatures follow Jonscher’s power law and the fitting parameters suggests that the conduction mechanism obey the correlated barrier-hopping model

Survey on the Biomedical Text Summarization Techniques with an Emphasis on Databases, Techniques, Semantic Approaches, Classification Techniques, and Similarity Measures

Abstract: Biomedical text summarization (BTS) is proving to be an emerging area of work and research with the need for sustainable healthcare applications such as evidence-based medicine practice (EBM) and telemedicine which help effectively support healthcare needs of the society. However, with the rapid growth in the biomedical literature and the diversities in its structure and resources, it is becoming challenging to carry out effective text summarization for better insights. The goal of this work is to conduct a comprehensive systematic literature review of significant and high-impact literary work in BTS with a deep understanding of its major artifacts such as databases, semantic similarity measures, and semantic enrichment approaches. In the systematic literature review conducted, we applied search filters to find high-impact literature in the biomedical text summarization domain from IEEE, SCOPUS, Elsevier, EBSCO, and PubMed databases. The systematic literature review (SLR) yielded 81 works; those were analyzed for qualitative study. The in-depth study of the literature shows the relevance and efficacy of the deep learning (DL) approach, context aware feature extraction techniques, and their relevance in BTS. Biomedical question answering
(BQA) system is one of the most popular applications of text summarizations for building self-sufficient healthcare systems and are pointing to future research directions. The review culminates in realization of a proposed framework for the BQA system MEDIQA with design of better heuristics
for content screening, document screening, and relevance ranking. The presented framework provides an evidence-based biomedical question answering model and text summarizer that can lead to real-time evidence-based clinical support system to healthcare practitioners.

Abstract: Biomedical text summarization (BTS) is proving to be an emerging area of work and research with the need for sustainable healthcare applications such as evidence-based medicine practice (EBM) and telemedicine which help effectively support healthcare needs of the society. However, with the rapid growth in the biomedical literature and the diversities in its structure and resources, it is becoming challenging to carry out effective text summarization for better insights. The goal of this work is to conduct a comprehensive systematic literature review of significant and high-impact literary work in BTS with a deep understanding of its major artifacts such as databases, semantic similarity measures, and semantic enrichment approaches. In the systematic literature review conducted, we applied search filters to find high-impact literature in the biomedical text summarization domain from IEEE, SCOPUS, Elsevier, EBSCO, and PubMed databases. The systematic literature review (SLR) yielded 81 works; those were analyzed for qualitative study. The in-depth study of the literature shows the relevance and efficacy of the deep learning (DL) approach, context aware feature extraction techniques, and their relevance in BTS. Biomedical question answering
(BQA) system is one of the most popular applications of text summarizations for building self-sufficient healthcare systems and are pointing to future research directions. The review culminates in realization of a proposed framework for the BQA system MEDIQA with design of better heuristics
for content screening, document screening, and relevance ranking. The presented framework provides an evidence-based biomedical question answering model and text summarizer that can lead to real-time evidence-based clinical support system to healthcare practitioners.