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Synthesis and characterization of Eu3+-doped Er2SiO5 phosphor are reported. The samples are prepared using the modified conventional solid-state synthesis technique with variable concentrations of doping ions and their structural studies are carried out by X–ray diffraction (XRD). The information on the morphology of the samples prepared with optimized doping ion concentrations is obtained by scanning electron microscopy (SEM). A photoluminescence (PL) analysis of the phosphor samples is also done for the fixed doping ion concentrations. The identified PL emission bands are attributed to the intra 4f transitions of a Eu3+ ion, such as 5D0→7F1 at 590 nm, 5D0→7F0 at 602 and 5D0→7F2 at 613 nm. The corresponding transitions of the doping ions and the concentration quenching effect are studied in detail. The 1931 Commission Internationale de l'éclairage (CIE) (x, y) chromaticity coordinates show the spectral distribution calculated from the PL emission spectrum. A thermoluminescence (TL) glow curve analysis is performed for variable doping ion concentrations, and the corresponding trap parameters are calculated using the Computerized Glow Curve Deconvolution (CGCD) technique. Our study shows that as-prepared phosphor may be useful for display devices. [ABSTRACT FROM AUTHOR]

We present new aspects of erbium- or ytterbium-doped pure gadolinium oxide (Gd2O3:Er3+/Yb3+) as a suitable candidate for drug delivery and magnetic resonance (MR) applications. The samples were prepared using the conventional sol–gel synthesis technique. The structural studies revealed that the prepared sample was monophased and crystallizes in a cubic structure. FTIR measurements confirmed the creation of Gd2O3:Er3+/Yb3+ phosphor. SEM micrographs clearly indicated that the particles crystallized in uniform shape, exhibiting nano-rod formation, with the particle size ranging from 55 to 5 nm. TEM images revealed that Er3+- and Yb3+-co-doped Gd2O3 nanoparticles were the collection of the nano-rods 2–4 nm thick and 18–20 nm long. Also, photoluminescence analysis of the phosphor samples for variable concentrations of doping ions was presented. When doped with Er3+/Yb3+, nano-rod Gd2O3 emits intense green emission and some red emission peaks, under a 980-nm near-infrared laser. Our study shows that as-prepared samples may be useful for optical imaging systems and that nano-rod formation may be used as a major host carrier for drug delivery. [ABSTRACT FROM AUTHOR]

While several devices can monitor temperature, measuring non-volatile thermal history is far more challenging, especially for sensors placed in hazardous settings like fires and explosions. Herein, the utilisation of thermoluminescent microparticles in thermal history sensors is discussed. These transparent dielectric microparticles can store charge carriers for very extended periods due to their wide distribution of trap states. In its most basic form, an Arrhenius expression is strongly temperature-dependent for determining the population of the trap states. When exposed to high temperatures for a brief period, a particle with filled traps will preferentially lose carriers in shallow traps. To ascertain the temperature and timing of the thermal event, this depopulation creates a mark on the particle luminescence. By being exposed to deep ultraviolet, X-ray, beta, or gamma radiation, which fills the traps with charge carriers, particles are prepared many months before a test, if required. No matter if they are embedded in garbage or other inert materials, one or more particles can nevertheless be made to emit light. Laboratory tests using microheaters and high-energy explosives in the field are used to test and analyse the technology. It is demonstrated that a variety of high-explosive conditions may be used to accurately detect temperatures in the $ 200\mathrm{^\circ C} $ 200 ∘ C to $ 500\mathrm{^\circ C} $ 500 ∘ C range using thermoluminescent materials like LiF:Mg,Ti, MgB4O7:Dy,Li, and CaSO4:Ce,Tb. The article will provide the utilisation of different luminescent materials for sensing thermal history and analysing the particle luminescence mechanism through different thermal models for developing improved thermal history sensing technologies. The thermal history reconstruction techniques are also discussed to predict the thermal history. Therefore, the article will pave the way to understanding the luminescent properties of thermoluminescent microparticles for developing state-of-the-art thermal history sensors for measuring non-volatile thermal history and temperature in extreme environments such as fires and explosions. [ABSTRACT FROM AUTHOR]

The term "soft computing" refers to a system that can work with varying degrees of uncertainty and approximations in real-life complex problems using various techniques such as Fuzzy Logic, Artificial Neural Networks (ANN), Machine Learning (ML), and Genetic Algorithms (GA). Owing to the low-cost and high-performance digital processors today, the use of soft computing techniques has become more prevalent. The main focus of this paper is to study the use of soft computing in the prediction and diagnosis of heart diseases, which are considered one of the major causes of fatalities in modern-day humans. The heart is a major human organ that can be affected by various conditions such as high blood pressure, diabetes, and heart failure. The main cause of heart failure is the narrowing of the blood vessels due to excess cholesterol deposits in the coronary arteries. The objective of this study is to review and compare the various soft computing techniques that are used for the prediction, diagnosis, failure, detection, identification, and classification of heart disease. In this paper, a comprehensive list of recent soft computing techniques in heart condition monitoring is reviewed and compared with an experiment with specific applications to developing countries including South Asian countries. The relevant experimental outcomes demonstrate the benefits of soft computing in medical services with a high accuracy of 99.4% from Fuzzy Logic and Convolutional Neural Networks, with comparable results from other competing state-of-the-art soft computing models. [ABSTRACT FROM AUTHOR]

In this research paper, we found both numerical and analytical solutions for the effect of chemical reaction on unsteady, incompressible, viscous fluid flow past an exponentially accelerated vertical plate with heat absorption and variable temperature in a magnetic field. The flow problem is governed by a system of coupled non-linear partial differential equations with suitable boundary conditions. We have solved the governing equations by an efficient, accurate, powerful finite element method (FEM) as well as Laplace transform technique (LTT). The evaluation of the numerical results are performed and graphical results for the velocity, temperature and concentration profiles within the boundary layer are discussed. Also, the expressions for the skin-friction, Nusselt number and the Sherwood number coefficients have been derived and discussed through graphs and tabular forms for different values of the governing parameters.