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Background: Pollution induced allergic rhinitis and respiratory symptoms is becoming a major health problem in the world for which still there is no safe and preventive treatment. Objectives: Conceive and evaluate the allergen preventive properties and clinical efficacy of an osmotic, polymeric, stable filmogen spray, called PCNS. Materials and Methods: Amb A 1 (ragweed), Der P 1 and 2 (dust mite), Bet v 1 (birch), Alt a 1 (Alternaria, fungus), and Fel d 1 (cat dander) allergens were exposed at a concentration of 5µg/ml (20 µl per tube) on the polymeric test product film (120 and 240µl layer) and the allergens crossing the barrier were quantified in the agar gel beneath the film. 0.40% HPMC and PBS solutions, tested identically, served as controls. Clinical efficacy of PCNS nasal spray was evaluated in patients suffering from allergic rhinitis and/or respiratory symptoms (29 in test product v/s 15 in saline controls) for 22 days. Nasal, ocular, respiratory symptoms and Rhino conjunctivitis Quality of Life Questionnaire (RQLQ) were measured. Statistical analyses: The normality of the populations was determined by the Shapiro-Wilk test, then statistical analysis was performed by two-tailed Student’s test for comparisons between two groups and the two-way ANOVA followed by the post hoc Bonferroni’s test for comparisons of multiple groups. p

Thermoluminescence (TL) and photoluminescence (PL) properties of the Gd3+ doped lanthanum zirconium phosphor (La2Zr2O7:Gd3+) are reported in this work. Gd3+ doped La2Zr2O7 (LZO) phosphor has been prepared via a high temperature solid state reaction method and it was prepared by using H3BO3 (as flux) and the preliminary materials were La2O3, ZrO2 and Gd2O3. The results of the XRD study shows that La2Zr2O7:Gd3+ phosphor has the cubic structure with 51.68 nm average crystallite size. The TL studies were carried out for the prepared phosphors using UV radiation (UV 254 nm), and a single glow peak was found in this study. Herein to extract the information about the positions of the TL emission at this work the peak shape methods are usage and the maximum peak exhibit the general order kinetics. In TL study the effect of UV exposure was investigated, it was found that it showed linearity with dose, which is helpful in TL dosimeters. The PL emission peaks of Gd -doped LZO phosphors were found to be in the region 450-650 nm, which was due to the 4f-4f transitions of Gd3+. More intense peaks at 468, 539, 589 and 627 nm were found at room temperature under excitation at 276 nm. Here the afterglow and photoluminescence behaviour of the Gd doped LZO phosphor is also reported.

Introduction: Allergic rhinitis (AR) in children is a common chronic pathology with a strong impact on patient quality of life. The main physiopathology affects the nasal cavity as a multi-factorial disease involving nasal mucosa damage, nasal inflammation with high concentrations of histamine, pro-inflammatory cytokines such as histamine, TNF-α, IL-4, IL-5, IL-6, IL-10, IL-13, and IgE antibodies on the nasal mucosa. Systemic entry of these proteins through damaged nasal mucosa maintains continued inflammatory and allergen cascades. Therefore, an ideal treatment should be multitarget in order to stop allergen exposure, inflammation, and nasal mucosa barrier degradation, but such treatments are nearly impossible to conceive. We envisaged an osmotic and protective nasal barrier film, not only capable of protecting the nasal mucosa from allergen exposure but also of trapping and neutralizing selected cytokines and cleaning the nasal surface continuously without using any harmful substance for children. Materials and Methods: We associated highly osmotic glycerol solution with specific plant polymers to conceive an osmotic but stable film. As plant polymers (tannins) can bind with selective proteins, a range of glycerol binding non-cytotoxic polymers were screened using the sandwich ELISA method to select those having binding affinity for allergen induced nasal proinflammatory cytokines. After verifying cytotoxicity and irritant potential, a 15-day observational clinical study was performed with approval from the ethics committee on 30 children aged between 4-13, suffering from allergic rhinitis. The test product (TP) was supplied in 15-ml nasal sprays and applied 2-3 times per day for a period of 15 days. Saline solution served as control (CP). The scores of nasal and ocular symptoms, effect on quality of life, eosinophil count in nasal smears, and need for antihistamine treatment was evaluated at the start, at 30 minutes and on days 2, 3 and 15 of treatment. Results: A few specific polymers were able to bind with selected cytokines and histamine at adequate filmogen concentrations. The osmotic film was stable, non-irritant and was able to clean the nasal mucosa continuously for 4-6h after each application. Clinical observations of Total Nasal Symptom Score (TNSS) grouping the scores of nasal congestion, runny nose, sneezing, and itching, revealed a strong decrease right after the 1st treatment in both groups but the reduction was much stronger and faster with the TP. The mean TNSS score reduction was 44.74% in CP vs 83.53% in the TP group after 7 days of treatment (p

Background: Pharyngitis, a common viral throat infection in children, involving inflammation, widespread local bacterial contamination and tissue destruction. When clinical signs appear, the disease already became multifactorial. In the absence of any multitarget treatment, we conceived a new generation of topical, osmotic, anti-inflammatory, throat surface cleaning polymeric film, capable of detaching and draining throat surface contaminants nearly instantly. Material and methods: A glycerol and polymer containing osmotic film was prepared. Osmotic film attracts hypotonic liquid from the throat tissue, which detach and drain throat surface contaminants and create a favorable environment for cell growth and healing. Specific pro-inflammatory cytokine and virus glycoprotein binding polymers were incorporated in the film to suppress the inflammation. An observational, randomized, placebo-controlled study was performed after the approval of ethical committee on 30 children aged between (3-15), presenting symptoms of acute pharyngitis. After randomization, test product (n=20) and saline control (n=10) solutions were applied as 3-4 throat sprays 4-5 times / day for 15-days. Change in all the key pharyngitis symptom (difficulty swallowing, throat inflammation, irritation, redness, and bacterial deposit) were evaluated employing two-tailed Student’s test for followed by the post hoc Bonferroni’s test for comparisons of multiple groups Results: Only a few specific polymers were able to bind with viral proteins and/or cytokines in adequate filmogen concentrations. Throat surface cleaning and cytokine neutralization strongly decrease all the pharyngitis symptoms and need for antibiotic therapy compared to controls (p

In this article, thermoluminescence (TL) and photoluminescence (PL) of Eu3+ doped La2Zr2O7 (LZO) phosphor with various concentrations were reported. A conventional solid-state reaction method was u...

Ravi Shrivastava,1 Remi Shrivastava,1 Bianca Johansen,1 Thibault Allain2,3 1VITROBIO Research Institute, Issoire, 63500, France; 2Laboratoire SANABEL, Paris, 75011, France; 3UMR 152 Pharma Dev, Université de Toulouse, IRD, UPS, Toulouse, FranceCorrespondence: Ravi Shrivastava Email rs@vitrobio.comBackground: Covid-19 infection starts in the nasal cavity when viral S1 and RBD proteins bind to the host cell ACE2 receptors, the virus multiplies, causes cell lysis, and enters the circulation. This triggers a strong cytokine release and inflammation of the nasal mucosa. A multitarget approach of cleaning the nasal mucosa and suppressing chances of nasal and systemic inflammation should minimize severe respiratory consequences. Unfortunately, no such treatments are yet available.Methods: We describe the conception of an osmotic polymeric film using an in vitro nasal mucosa mimicking model, containing polymers to neutralize Covid-19 specific viral S1, RBD proteins and selected proinflammatory cytokines.Results: The filmogen barrier forms a stable and osmotic film on the nasal mucosa. Hypotonic liquid exudation from the nasal surface detaches and drains the inflammatory cytokines and other contaminants towards the film where selected polymers bind and neutralize SARS-CoV-2 spike S1 and RBD protein as well as Covid-19 disease-specific key pro-inflammatory IL-6, TNF-α, IL-10, IL-13, and GM-CSF cytokines.Conclusion: Minimizing the nasal surface concentration of pro-inflammatory cytokines and viruses should help nasal mucosa repair and avoid immune stress. This nearly instant, simple, scientific, safe, and logical approach should help attenuate Covid-19 induced systemic inflammation at an early stage without being affected by viral S1 spike protein mutations.Keywords: filmogen glycerol, antiviral, anti-cytokines, anti-inflammatory, Covid-19, S1, RBD

In the present paper, we report security analysis of an effective method of scrambling i.e. XOR technique, which may be used as an important component in visual cryptography. Histogram of scrambled or encrypted images expressed that pixel values are distributed quite uniformly. This implies that nothing can be guessed about the original image using the encrypted image. For analyzing the complexity of encrypted images, information entropy, the correlation coefficient of adjacent pixels values were also calculated. Values of horizontal correlation, vertical correlation, and information entropy reflected that the complexity and randomness of pixel values are quite high for XOR cipher. Now a day’s differential attack has been very common. Keeping the same in the mind, we have calculated Unified Average Changing Intensity (UACI) and the Number of Pixels Change Rate (NPCR), to exhibit the ability of encrypted image using XOR cipher to resist the differential attack. So we can say that XOR cipher is useful for secure transmission of an image.

In the present paper, we report an effective method of multilevel scrambling followed by affine encryption, which may be used as one of the useful tools in visual cryptography. A sample image is scrambled for six times using a specific algorithm. Toner distributions of scrambled images were studied using their histograms. The results of histogram expressed that the effectiveness of scrambling increased with its increasing stages and it becomes almost ideal when the image after affine encryption is taken. In order to judge the complexity level of scrambling, horizontal & vertical correlation of adjacent pixels and Information Entropy of different scrambled images were also calculated. Values of horizontal & vertical correlation and information entropy reflected that the complexity and randomness of pixels increase with increasing stages of scrambling. It also indicated that the randomness doesn’t change much after the fifth stage of scrambling and affine encryption enhanced the level of security by a large extent.

CeO2:M (Eu3+, Er3+ and Dy3+) phosphors were synthesized by modified solid-state reaction technique at variable concentrations of Eu3+, Er3+ and Dy3+. This technique is suitable for large-scale production and it is less time-consuming. The prepared samples were characterized by X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), and Photoluminescence (PL) decay curve analysis. XRD patterns of the prepared samples confirm the cubic fluorite crystal structure of all phosphors. Crystallite size was calculated by using well known Scherer’s formula. SEM images express good surface morphology with nanoflower like shape. Comparative studies of photoluminescence decay curves of CeO2:M (Eu3+, Er3+ and Dy3+) with different concentrations of dopant have been done. Decay constants for all prepared phosphors were calculated by curve fitting technique. Samples were excited under UV radiation for few nanoseconds at room temperature. The PL decay curves were measured for 5D0→7F1 transition of CeO2:Eu3+,4S3/2→4I15/2 transition of CeO2:Er3+ and 4F9/2→6H13/2 transition of CeO2:Dy3+ phosphors. Decay curve for CeO2:Eu3+ (1.5 mol%) phosphor shows optimum concentration with higher intensity of photoluminescence signals and comparatively higher decay constants.

This paper reports the preparation of Eu 3+ doped Gadolinium oxyorthosilicate (Gd 2 SiO 5 :Eu 3+ ) phosphor with different concentration of Eu 3+ (0.1–2.5 mol%) using the modified solid state reaction method. The synthesis procedure of the Gd 2 SiO 5 :Eu 3+ phosphor using inorganic materials such as Gd 2 O 3 , silicon dioxide (SiO 2 ), europium oxide (Eu 2 O 3 ) and boric acid (H 3 BO 3 ) as flux is discussed in detail. The prepared phosphor samples were characterized by using X-Ray Diffraction (XRD), Field Emission Gun Scanning Electron Microscopy (FEGSEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), Photoluminescence (PL) and Thermoluminescence (TL). The Commission Internationale de l′Eclairage(CIE) coordinates were also calculated. The PL emission was observed in the 350–630 nm range for the Gd 2 SiO 5 :Eu 3+ phosphor. PL excitation peaks were observed at 266, 275, 312 and 395 nm while the emission peaks were observed at 380, 416, 437, 545, 579, 589, 607, 615 and 628 nm. The emission peak at 615 nm was the most intense peak for all the different Eu 3+ concentration samples. From the XRD data, using the Scherrer's formula, the average crystallite size of the Gd 2 SiO 5 :Eu 3+ phosphor was calculated to be 33 nm. TL was carried out for the phosphor after both UV and gamma irradiation. The TL response of the Gd 2 SiO 5 :Eu 3+ phosphor for the two different radiations was compared and studied in detail. It was found that the present phosphor can acts as a single host for red emission (1.5 mol%) for display devices and light emitting diode (LED) and white light emission for Eu 3+ (0.1 mol%) and it might be used as a TL dosimetric material for gamma dose detection.

Luminescence behaviour was displayed by dysprosium (Dy3+) doped BaTiO3 phosphor which was synthesized via solid state reaction method. The method is suitable for large scale production and useful for production of micron size phosphor. The sample was characterized by X-ray diffraction technique and crystallite size was calculated using Scherer’s formula. Effects of optimized concentration of Dy3+ on its thermoluminescence glow curve analysis were carried out for γ irradiation. For fixed concentration of dysprosium ions the TL glow curve was recorded using 6.7 °C s−1 heating rate. Also for variable γ dose 1–2.5 kGy and optimized concentration of dysprosium ion i.e. 4 mol% were carried out. It is found that TL glow curve shows linear response with γ dose. Kinetic parameters were calculated using computerized glow curve deconvolution technique. Photoluminescence study of Dy3+ doped BaTiO3 phosphor was carried out and it is found that the PL emission spectra in visible region had blue, green and red emission wavelength. CIE coordinate shows color rendering index and correlated color temperature for white light emission of Dy3+ doped BaTiO3 phosphor. It may be used for visible light emission in display device applications and TL dosimetric applications.

Dy3+ doped Lanthanum Aluminate phosphors are prepared for different concentrations of dopant and the luminescent properties of the phosphor are studied. High temperature modified solid-state reaction method is used for the synthesis. XRD analysis confirms the formation of LaAlO3:Dy3+ phosphor. Average crystallite size calculated is 40.085 nm.Thermoluminescence study of UV induced LaAlO3:Dy3+ phosphor is discussed in this paper. Thermoluminescence glow peak is recorded for different UV exposure time and for different concentrations of dopant. Kinetic parameters such as shape factor, activation energy, order of kinetics are calculated by using computerized glow curve deconvolution technique. Activation energy varies from 0.63 to 0.72 eV. The TL glow curve intensity varies nearly linear with increasing UV dose. Photoluminescence (PL) emission spectra are recorded for different concentrations of dopant. Highest intensity of PL emission was obtained for 1.5 mol% of Dy3+ doped LaAlO3 phosphor. The excitation spectra of Dy3+ doped LaAlO3 phosphor monitored at 550 nm shows broad band around 260 nm and a sharp peak at 394 nm. Peaks with lower intensity are obtained at 320 nm, 363 nm and 384 nm. In the Pl emission spectra, peak at 554 nm (yellow greenish) has highest intensity. Peaks with less intensity are obtained at 466 nm (blue), 645 nm (orange red) and 740 nm (brownish red). Pl intensity varies linearly with increasing concentration of dopant. CIE chromaticity coordinates are calculated for LaAlO3:Dy3+ (1.5 mol%), x = 0.3586 and y = 0.5421 which corresponds to yellow–greenish region. The prepared phosphor may find application in dosimetry and optical devices.

This paper reports synthesis of Ce3+ ions-doped Gd2SiO5 phosphor powders prepared by modified solid state reaction method, which is most suitable method for large-scale production. Starting materials used for sample preparation were Gd2O3, SiO2 and CeO2 with variable concentration of cerium (0.1 mol% to 2.5 mol%) with fixed amount of boric acid (0.05 mol%) as flux. PL excitation spectra was found at 260 nm while the emission spectra was found at 365, 378, 555, 602, 607 and 627 nm for lower Ce3+ doping concentration which are attributed to the Gd3+ ion transitions. For higher concentration of Ce3+ we get broad emission spectra from 350 to 550 nm which is characteristics of Ce3+ ion transition. Commission Internationale de l’Eclairage co-ordinate (CIE) of this phosphor is x = 0.170, y = 0.029, in the violet region for 2.5 mol% of cerium. TL glow curves were recorded for different doses of UV exposure and gamma ray dose at a heating rate of 5° C s−1. The kinetic parameters such as activation energy “E”, the order of kinetics “b”, and the frequency factor “s” of Gd2SiO5:Ce3+ have been calculated by using peak shape method. Sample shows general order kinetics for most of the peaks. The effect of Ce3+ concentration on TL intensity was also studied and found that the intensity is maximum for 0.1 mol% and then decreases with increasing concentration of Ce3+. The present phosphor can acts as a single host for violet-blue emission (2.5 mol%) for display devices as well as may be used for thermoluminescence dosimetric material under UV & gamma dose.

CeO $_{{2}}$ :Dy $^{{3+}}$ phosphors were synthesized by modified conventional solid-state reaction method. The formation of a CeO $_{{2}}$ structure is confirmed via XRD studies. The luminescence measurement upon excitation in ultraviolet and visible range shows the characteristics Dy $^{{3+}}$ excitation and emission. The occurrence of charge transfer band is explained in detail. The emission spectrum of Dy ions consists mainly of several groups of lines in the 450–625-nm region, due to the transitions from the ${}^{{4}}$ F $_{{9/2}}$ - $_{{6}}$ H $_{{15/2}}$ (blue emission) and the $^{{4}}$ F $_{{9/2}}$ - $_{{6}}$ H $_{{13/2}}$ (yellow emission) of Dy ions. The phenomena of concentration quenching are explained on the basis of electron phonon coupling and multipolar interaction. Different spectral parameters are calculated via the Judd Ofelt approach. The purity of the white light emission is also examined, and it makes Dy $^{{3+}}$ doped CeO $_{{2}}$ a promising candidate for applications in displays and optical device.

Di-barium magnesium silicate doped with Eu $^{2+}$ and Tm $^{3+}$ phosphors were prepared for different concentrations of Tm $^{3+}$ ions keeping the concentration of Eu $^{2+}$ as 0.5 mol%. Photoluminescence (PL) studies of prepared samples were carried out. Emission spectra exhibited optimum green color emission at 509 nm when Tm $^{3+}$ was 1.5 mol%. Emission is expected to arise due to the transition of Eu $^{2+}$ ions from any of the sublevels of 4d $^{6}$ 5f $^{1}$ to its ground state ( ${}^{8}$ S $_{7/2})$ . This sample with 1.5 mol% of Tm $^{3+}$ is taken for X-ray diffraction analysis. XRD pattern confirmed that the sample follows monoclinic structure with C 1 2/c 1 (15) space group. Scanning Electron Microscope image of the sample exhibited the uniform morphology with average particle size of 222.54 $\mu$ m . Thermoluminescence (TL) glow curves of the sample for different UV irradiation were also recorded which presented single broaden peak centered at about ${\hbox{91}}\ ^{\circ}$ C. Phosphorescence decay curve was indicative of presence of dual exponential decaying section with a fast decay followed by a long decaying part.

This paper reports the preparation of CaTiO3 doped with various concentrations of Dysprosium (II) using solid state reaction technique. X-ray diffraction patterns of the sample were taken. Observed XRD pattern was matched using software match2!. The pattern was matched significantly with the crystallographic open database card (COD – 96-101-1212) which is a standard card for CaTiO3. This matching exhibited that, the prepared sample is cubic in structure with space group P m − 3 m (221). Photoluminescence (PL) studies of the samples were also done. PL intensity was found increasing with increasing dopant concentration and maximum intensity was noted at 2.0 mol% concentration of Dy3+, thereafter concentration quenching occurred. Emission Peaks were centered at 483 nm (4F9/2➔6H15/2) and 576 nm (4F9/2➔6H13/2) respectively. For studying the concentration quenching, the critical distance for energy transfer and electric multipolar character were estimated. The value of multipolar character expressed that, the transition in emission spectra is a dipole – dipole (d-d) transition. Commission Internationale de l’Eclairage (CIE) coordinates was found as (0.36, 0.39), which is near to white light. Colour Correlated Temperature (CCT) was 4489 K which was indicative of cool appearance of the light emitted.

The upconversion (UC) of the rare earth doped MY2O4 (M=Ba, Sr, Ca) has been extensively investigated due to their potential applications in many fields, such as color display, high density memories, optical data storage, sensor and energy solar cell, etc. Many series of them, especially the Er3+, Yb3+ doped MY2O4 were studied in this chapter, due to the thermal and mechanical toughness, high optical transmittance from the ultraviolet to the infrared regions, and a low nonlinear refractive index compared to the other commercial laser glasses. The energy transfer (ET) mechanism of rare earth doped phosphor plays an important role in the upconversion process.

This paper reports the synthesis of ${\hbox{Gd}}_{2}{\hbox{SiO}}_{5}$ phosphor by a modified solid-state reaction method. The sample was characterized by the X-ray diffraction (XRD) technique, and the XRD spectrum matched with JCPDS card specifically appeared for ${\hbox{Gd}}_{2}{\hbox{SiO}}_{5}$ . This is a confirmation of proper preparation of the sample. Photoluminescence (PL) study of the sample was done. PL excitation spectra was found at 242, 275, 312 nm while the emission spectra was found at 380, 416, 439, 489, 545, 589, 607, 617, and 630 nm. The Commission Internationale de l'Eclairage (CIE) co-ordinate of this phosphor is ${\rm x}= 0.294$ , ${\rm y}= 0.222$ , in the purplish white color touches white line boundary. Thermoluminescence (TL) glow curves were recorded for different doses of $\gamma$ - ray exposure at a heating rate of ${\hbox{6.7}}\ ^{\circ}{\hbox{C}}{\cdot}{\hbox{s}}^{-1}$ . The kinetic parameters of ${\hbox{Gd}}_{2}{\hbox{SiO}}_{5}$ have been calculated by using peak shape method. Sample shows general order kinetics for most of the peaks. Also, the TL glow curves of the sample were measured at various delay times. With increased delay time, the intensity of the TL peak decays and the position of the peak shifts toward a higher temperature, indicating the considerable re-trapping associated with general order kinetics. The present phosphor can act as a host for purplish white color emission (touches white line) for display devices and light emitting diode (LED), as well as may be used for thermoluminescence dosimetric material under $\gamma$ dose.

Eu2+ and Tb3+ doped Ca2MgSi2O7 phosphors were synthesized by conventional solid-state reaction. The phase formation was confirmed by X-ray powder diffraction technique and refined lattice parameters were calculated by rietveld refinement process using Celref v3. The photoluminescence (PL) excitation and emission spectra were investigated. The phosphors exhibited broaden green emitting luminescence peaking at 520 nm when excited at 374 nm source. Morphological studies were carried out using Scanning electron microscopy (SEM) images of the sample with optimum PL emission. The dependence of photoluminescence intensity on co-dopant concentration and the kinetic parameters were also reported. Time resolved fluorescence spectroscopy (TRFS) is used to investigate the decay in luminescence signals with respect to time. The sample proved to be a good long lasting material, which makes it useful in emergency signs, textile printing, textile exit sign boards and electronic instrument dial pads etc.

The phosphor of BaZrO3 doped with different concentration of Eu3+ ions (0.1, 0.5, 1 mol%) was prepared by solid–state reaction method. The prepared samples were characterized by X-ray diffraction (XRD), photoluminescence (PL) and thermoluminescence (TL) techniques. Analysis of XRD data shows the formation of perovskite structure of prepared phosphor. The room temperature excitation spectra vary with the Eu3+ concentration and consist of an intense charge transfer band and weak f–f transitions. The PL emission spectra, excited at 254 nm, consist of 4f–4f emission transitions from the 5D0 excited level of the Eu3+ ions to the 7FJ (J = 0–3) levels. The dependence of luminescence intensity on the Eu3+ concentration in BaZrO3:Eu3+ was studied. The present phosphor can act as single host for intense red emission for display devices application. Commission internationale de I'Eclairage techniques gives information about correlated color temperature and prominent emissions in PL emission spectra. Detail process and possible mechanism for PL and TL are studied and discussed in this paper. For the variable concentration of Eu3+ ions on PL studies shows the PL intensity increase with increasing the concentration of dopant. In TL glow curve the optimized concentration in 1 mol% for UV irradiated sample. The kinetic parameters were calculated by computerized glow curve deconvolution (CGCD) technique.

In this review we have studied number of research papers related to white light emission from Dy3+ doped different host matrices. It is observed that most of the Dy3+doped aluminates, silicates, borates etc., emitted blue, green and red colour with specific intensities so that CIE coordinates, appeared near to white light. Correlated Colour Temperature(CCT) values of these phosphors expressed that the white light emission produced, was adaptable to human eyes. Dy3+ ions act as activator in each case. Four peaks at approximately 480,575, 670, and 757 nm could be seen in most of the Dy3+ doped phosphors. Expected transition responsible for these peaks are 4F9/2 → 6H15/2 (Blue Colour), 4F9/2 → 6H13/2 (Green-Yellow Colour), 4F9/2 → 6H11/2 (Red Colour) and 4F9/2 → 6H9/2(Brownish Red Colour). Few of the discussed phosphors exhibited long phosphorescence, starting from several minutes to few hours. Mechanism responsible for long lasting white light emission was also discussed. Five different factors, to recognize the phosphors for its suitability as commercial white light phosphor have been discussed.

Yttrium aluminum perovskite (YAP) is a promising high temperature ceramic material, known for its mechanical, structural and optical properties. YAP’s also known as an ideal host material for solid-state lasers and phosphors. In this work, Ce 3+ doped YAlO 3 phosphors were synthesized by solid state reaction method, which is very suitable technique for large scale production. A prepared phosphor was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Photoluminescence spectra and Thermoluminescence (TL) glow curve study. The starting reagents used for sample preparation are Y 2 O 3 , Al 2 O 3 and CeO 2, boric acid used as a flux. Ratio of Y:Al was 1:1 which shows perovskite structure confirmed by the X-ray diffraction (XRD) study. The entire prepared sample was studied by PL excitation and emission spectra. Prominent peak at 446 nm (blue emission) which shows broad emission spectra of photoluminescence. It proves that prepared phosphor can act as a single host for blue emission of light and can be used for display applications. Commission Internationale de I’Eclairage (CIE) techniques proves the blue emission of light ( x = .148, y = .117). TL glow curve analysis of prepared phosphor shows the prominent peak at 189 °C for the variable UV exposure time and high temperature peak shows the more stability and less fading in the prepared phosphor. Kinetic data of prepared phosphor were evaluated by peak shape method for variable UV exposure time (5–25 min).

Di-barium magnesium silicate phosphors doped with europium and dysprosium were prepared under a weak reducing atmosphere. X-ray diffraction pattern of the sample was also done that confirmed the proper preparation of the phosphor. Scanning electron microscope (SEM) images confirmed that the sample has regular surface and uniform grain size distribution. Comparative studies of phosphorescence decay of Ba2MgSi2O7:Eu2+, Dy3+ phosphors with different concentration of Dy3+ were done. The phosphor with 0.5/1.5 mol% of Eu/Dy, exhibited optimum green color afterglow properties. This emission is expected to arise due to transition of Eu2+ ions from any of the sublevels of 4f65d1 configuration to 8S7/2 level of the 4f7 configuration. For a suitable trap depth, the trap concentration is expected to be proportional to the concentration of Dy3+. These traps are responsible for holding the charge career for a reasonable time, subsequently for increasing the time of afterglow. Hence, optimum Dy3+ concentration produces the longer afterglow duration with higher intensity of luminescence signals. Trap depth were also calculated using thermoluminescence glow curve which was indicative of formation of traps suitable for long afterglow.

Tin (Sn)-doped cadmium zinc sulphide nanoparticles (CdZnS: Sn) were synthesized by the chemical bath deposition method with two different concentrations of Sn (2 and 4 mol%). X-ray diffraction (XRD) pattern reveals the formation of CdZnS nanoparticles with cubic and hexagonal structure. It was observed that the presence of Sn does not alter the structure of CdZnS. Average crystallite size was measured from XRD data by using Scherrer’s formula. From the study of absorption spectra, band-to-band absorption was obtained at 460 and 490 nm, respectively, for the Sn-doped (2 and 4 mol%) CdZnS nanoparticles. Energy bandgap for undoped and Sn-doped CdZnS varies from 3.5 to 2.9 eV with error ±0.05 eV. The presence of Sn was confirmed by energy-dispersive X-ray analysis. The effect of dopant concentration on the photoluminescence (PL) intensity has also been studied. The PL emission peak has been observed at 540, 550 and 560 nm for the Sn-doped (CdZnS, CdZnS 2 mol% and CdZnS 4 mol%), respectively, nanoparticles. XRD and PL analyses demonstrate that the Sn2+ ions uniformly substitute Cd2+ sites or interstitial sites in CdZnS lattice, which influence the optical properties. Increase in the concentration of Sn shifts the UV–vis absorption spectra and PL emission spectra towards higher wavelength side. Particle size and the crystallinity of CdZnS : Sn nanoparticles were confirmed through atomic force microscopy.

In this paper, we report the dysprosium doped di-calcium magnesium di-silicate namely Ca2MgSi2O7:xDy3+ (x = 1.0, 1.5, 2.0, 2.5 and 3.0 mol%) phosphors were prepared by traditional high temperature solid state reaction method. Phosphors with optimum photo-luminescence intensity [Ca2MgSi2O7:Dy3+ (2 %)] were characterized by X-ray diffraction (XRD) technique. The crystal structure of sintered phosphors were an akermanite type which belongs to the tetragonal crystallography with space group $$ {\text{P}}\overline{ 4 2}_{1} {\text{m}} $$ . The chemical composition of the sintered phosphor Ca2MgSi2O7:Dy3+ (2 %) was confirmed by the energy dispersive X-ray spectroscopy (EDS). Under the ultraviolet excitation, the emission spectra of Ca2MgSi2O7:xDy3+ (x = 1.0, 1.5, 2.0, 2.5 and 3.0 mol%) phosphors were composed of broad band with the characteristic emission of Dy3+ ions are peaking at 475 nm (blue), 577 nm (yellow) and 678 nm (red), originating from the transitions of 4F9/2 → 6Hj state (where j = 15/2, 13/2, 11/2). The combination of these three emissions constituted white light as indicated on the Commission Internationale de l’Eclairage chromaticity diagram. The possible mechanism of the prepared white light emitting Ca2MgSi2O7:xDy3+ (x = 1.0, 1.5, 2.0, 2.5 and 3.0 mol%) phosphors were also investigated. Investigation on decay property show that phosphor held fast and slow decay process. The peak of mechanoluminescence (ML) intensity increases linearly with increasing impact velocity of the moving piston, which suggests that this phosphor can be used as sensors to detect the stress of an object. Thus the present investigation indicates that piezo-electricity is responsible to produce ML in prepared phosphors.

In the present investigation dysprosium doped strontium aluminate phosphor was prepared by combustion synthesis method. The crystal structure of the prepared phosphor was consistent with standard monoclinic phase with a space group P21. According to the TEM analysis, the particle size was found to be in the nanometer range. The trap parameters which are mainly activation energy (E), frequency factor (s) and order of the kinetics (b) were evaluated by using the peak shape method. Under the ultraviolet (365 nm) excitation, photoluminescence (PL) spectra showed characteristic emission bands at 480 (blue), 573 (yellow) and 670 nm (red) due to 4F9/2 → 6H15/2, 4F9/2 → 6H13/2 and 4F9/2 → 6H11/2 transitions of Dy3+ ions. Combination of these three emissions constituted as white light confirmed by the Commission Internationale de L’Eclairage (CIE) chromatic coordinate diagram and possible mechanism of white light emitting SrAl2O4:Dy3+ phosphor was also investigated. The value of correlated color temperature (CCT) was found, well within the defined acceptable range (5965 K). The mechanoluminescence (ML) intensity of SrAl2O4:Dy3+ phosphor increases linearly with increasing impact velocity of the moving piston. Thus, the present investigation indicates the piezo-electricity was responsible to produce ML in prepared phosphor.

The Ca2MgSi2O7:Eu2+ and Ca2MgSi2O7:Eu2+, Dy3+ long afterglow phosphors were synthesized under a weak reducing atmosphere by the traditional high temperature solid state reaction method. The synthesized phosphors were characterized by powder X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) techniques. The luminescence properties were investigated using thermoluminescence (TL), photoluminescence (PL), long afterglow, mechanoluminescence (ML), and ML spectra techniques. The crystal structure of sintered phosphors was an akermanite type structure, which belongs to the tetragonal crystallography. TL properties of these phosphors were investigated, and the results were also compared. Under the ultraviolet excitation, the emission spectra of both prepared phosphors were composed of a broad band peaking at 535 nm, belonging to the broad emission band. When the Ca2MgSi2O7:Eu2+ phosphor is co-doped with Dy3+, the PL, afterglow and ML intensity is strongly enhanced. The decay graph indicates that both the sintered phosphors contain fast decay and slow decay process. The ML intensities of Ca2MgSi2O7:Eu2+ and Ca2MgSi2O7:Eu2+, Dy3+ phosphors were proportionally increased with the increase of impact velocity, which suggests that this phosphor can be used as sensors to detect the stress of an object.

Present paper reports the preparation of Sr 2 MgSi 2 O 7 doped with Dy 3+ ions by modified high temperature solid state reaction technique. Samples were prepared for different concentration of Dy 3+ (0.5, 1.0, 1.5, 2.0 and 2.5 mol%). Sample with optimum photoluminescence intensity was characterized by X-ray diffraction (XRD) technique. Observed XRD spectrum matched with crystallographic open database card specifically appeared for Sr 2 MgSi 2 O 7 phosphor. This is a confirmation of proper preparation of the sample. Photoluminescence studies of these samples were done. Emission spectra exhibited 5 prominent peaks at 480, 490, 575, 590 and 660 nm respectively. In this case Dy 3+ acts as an activator. Peaks centered at 480 and 490 nm are due to the transition 4 F 9/2 → 6 H 15/2 (blue color) of Dy 3+ ions occupied at different sites. Similarly 575 and 590 nm peaks are originated due to transition 4 F 9/2 → 6 H 13/2 (yellow–orange color) of Dy 3+ ions occupied at different sites. Emission at 660 nm is due to transition 4 F 9/2 → 6 H 11/2 (red color). CIE coordinates have been calculated for each sample and its value exhibited that, overall emission is near white light. In order to investigate the suitability of the samples as white color light sources for industrial uses, correlated color temperature (CCT) and color rendering index (CRI) were calculated. Values of CCT and CRI were found, well within the defined acceptable range.

Cerium-doped cadmium zinc sulfide nanoparticles (CdZnS:Ce) were synthesized by chemical bath deposition method with three different concentrations of cerium (1.2, 2.5 and 3.84 mol%). X-ray diffraction pattern revealed the formation of cadmium zinc sulfide nanoparticles with cubic and hexagonal structure. It was observed that the presence of ceria did not alter the structure of CdZnS. Average crystallite size was measured from X-ray diffraction data by using Scherrer’s formula. From the study of absorption spectra, band-to-band absorption was obtained at 455 and 470 nm, respectively, for the Ce-doped (2.5 and 3.84 mol%) CdZnS nanoparticles. Energy band gap for undoped and Ce-doped CdZnS varied from 3.45 to 3.15 eV with error ±0.05 eV. The presence of cerium was confirmed by energy-dispersive analysis of X-rays. The effect of dopant concentration on the photoluminescence intensity was also studied. The photoluminescence emission peak was observed at 520, 540 and 560 nm, respectively, for the Ce-doped (1.2, 2.5 and 3.84 mol%) CdZnS nanoparticles. X-ray diffraction and photoluminescence analysis demonstrated that the Ce3+ ions uniformly substituted Cd2+ sites or interstitial sites in CdZnS lattice, which influenced the optical properties. An increase in the concentration of cerium shifted the UV–Vis absorption spectra and photoluminescence emission spectra toward the higher wavelength side. Particle size and the crystallinity of CdZnS:Ce nanoparticles were confirmed through transmission electron microscopy and selected area electron diffraction patterns.

Di-barium magnesium silicate phosphor doped with Eu2+ and Dy3+ was prepared using a solid-state reaction technique under a reducing atmosphere. The sample underwent impulsive deformation by impact from a piston for mechanoluminescence (ML) investigations. The temporal ML characteristics of the phosphor were observed, which expressed a single sharp peak with a long decaying period. To investigate the luminescence centre responsible for the ML peak, the ML spectrum of the phosphor was also observed. The recorded ML spectrum was similar in shape and peak wavelength to the photoluminescence (PL) spectrum, which verifies the existence of a single emission centre due to the transition of Eu2+ ions, i.e. transitions from any of the sublevels of the 4f65d1 configuration to the 8S7/2 level of the 4f7 configuration. Decay rates for different impact velocities were also calculated using curve-fitting techniques. The time of the ML peak and the rate of decay did not change significantly with respect to increasing impact velocity of the load and peak ML intensity varied linearly. The mechanism of the ML emission was also discussed. Copyright © 2015 John Wiley & Sons, Ltd.

Objective: External hemorrhoids are enlarged, bulging blood vessels in and around the anus and lower rectum. They associate several pathologies such as engorged, edematous and inflamed sinusoids, with numerous proinflammatory cytokines on their surface, requiring a multi-target therapeutic approach. In the absence of any effective treatment, we assessed a newly conceived osmotically active, hypertonic, filmogen solution (Pileseptine-e) directed at attracting hypotonic liquid and helping suppress inflammation. The clinical efficacy and safety of Pileseptine-e on external hemorrhoids was evaluated in this study.Methods: A 2-week treatment + 1-week follow-up, comparative, randomized, double blind, clinical trial with Pileseptine-e (n=37, test product) versus saline spray (n=17, placebo) was performed in patients suffering from external hemorrhoids. Test and placebo products were applied as 3-4 sprays, 3-4 times per day, for 14 consecutive days. Parameters were evaluated employing a 0-4 or 0-10 scoring scale, before treatment (baseline, T0), 2h after 1st treatment, and on Days 2, 3, 8, and 14, with follow-up check on Day 21.Results: The test product induced an instant and strong outward exudation of liquid from inside the edematous hemorrhoids, thereby cleaning their surface, keeping it hydrated, and reducing pain and itching. A strong reduction in the size of hemorrhoids and rectal bleeding was also observed, which improved the quality of life of the patients considerably. The placebo product also provided noticeable symptomatic relief, but without effect on the size of hemorrhoids. No adverse effects were observed in any patient.Conclusion: Reducing edema to allow hemorrhoidal volume to regress, and to normalize the structural physiology of the anal area, is the primary prerequisite to treat external hemorrhoids. Pileseptine-e is an antiedematous, cleaning, hydrating, safe and non-irritant filmogen solution that represents great advancement in the treatment of external hemorrhoids.

Di-calcium magnesium silicate phosphor doped with Eu2+ and Dy3+ was prepared using solid state reaction technique under a reducing atmosphere. Prepared sample suffered an impulsive deformation with an impact of a piston for mechanoluminescence (ML) investigations. A temporal characteristic of ML of the phosphor was observed, which expressed single sharp peak with a long decaying section. In order to investigate about the luminescence centre responsible for ML peak, ML spectrum of the same phosphor was also observed. ML spectrum recorded shown similarity in shape as well as peak wavelength with Photoluminescence (PL) spectrum that verifies the existence of single emission centre due to the transition of Eu2+ ions i.e. transitions from any of the sublevels of 4f65d1 configuration to 8S7/2 level of the 4f7 configuration. Decay rates for different impact velocities were also calculated using curve fitting technique. Time of ML peak and rate of decay did not change largely with respect to increasing impact vel...

In this paper we have compared the average power, leakage power, leakage current and leakage voltage of a 3-T DRAM circuit. To compare the performance of 3T DRAM we use the FinFET approach and SVL technique. This is the type of gate structure which helps to reduce leakage current amount and overcomes some type other short-channel effects and enhanced electrical control over the channel conduction. SVL is the technique which used to decrease leakage during both the stand-by mode and active mode. DRAM is used in several processors for data memory purpose. In modern day personal computers DRAM is used as the main memory. The Off-state leakage current is the main reason behind power dissipation in DRAM structures. The basic advantage of using DRAM is simplicity in its structure.

Europium and dysprosium-doped calcium magnesium silicate powder with different concentrations of dysprosium were synthesized using solid-state reaction. The Fourier transform infrared (FT-IR) spectra confirmed the proper preparation of the sample. The prepared phosphors were characterized using photoluminescence excitation and emission spectra. Prominent green colour emission was obtained under ultraviolet excitation. The thermoluminescence glow curves of the samples were measured at various delay times. With increased delay time, the intensity of the thermoluminescence peak decays and the position of the thermoluminescence peak shifts towards higher temperature, indicating the considerable retrapping associated with general order kinetics.

Europium- and dysprosium-doped strontium magnesium silicate powder with different concentration ratios of dysprosium were synthesized using solid-state reaction. The XRD pattern confirmed the proper preparation of the sample. The prepared phosphors were characterized using photoluminescence excitation and emission spectra. Prominent blue color emission was obtained under ultraviolet excitation. The thermoluminescence (TL) glow curves of the sample were measured at various delay times. With increased delay time, the intensity of the TL peak decays and the position of the TL peak shifts towards a higher temperature, indicating the considerable retrapping associated with general order kinetics.

The present paper reports the general features of luminescence and various characterization techniques and mainly focused on the review of optical studies of rare earth (RE)-doped barium aluminate phosphor (BaAl2O4). The paper is a short review of various methods of preparation of this phosphor and its characterization by thermoluminescence, photoluminescence, mechanoluminescence, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, etc.; the corresponding results were compared. The RE dopants mainly include Eu, Dy, and Nd.

This paper reports thermoluminescence glow curves of Eu3+, Dy3+-doped Ba2MgSi2O7 phosphor for different UV exposure times. Kinetic data were evaluated by the peak-shape method. The glow curves shift toward higher intensity with increasing exposure time to UV at 365 nm. When the heating rate was 5 °C s−1, peaks were observed at 101.76, 109.69, 102.67, and 104.05 °C, respectively, after UV exposure for 5, 10, 15, and 20 min. The glow peaks are indicative of second-order kinetics. Different kinetic data, i.e. trap depth, order of kinetics, activation energy, and frequency factor were also calculated. To evaluate the persistence characteristics of the luminescence of the phosphor, the lifetime of the charge in the trap was calculated; it was 348, 660, 368, and 428 s for UV exposure of 5, 10, 15, and 20 min, which indicates the luminescence of the phosphor is persistent.

Objective: Cough reflex is the body’s protective mechanism to prevent entry of foreign material into the lower respiratory tract. Cough is usually caused by a primary viral infection: virus growth causes lysis of throat mucosa cells, leading to inflammation, secondary bacterial infection, accumulation of contaminants on the throat, increased mucus secretion, and coughing. To treat this multifactorial condition, an effective treatment should be multitarget, but no currently available drug fulfils this complex yet essential requirement. We developed a hypertonic, highly osmotic, filmogen liquid bandage which can mechanically clean the throat surface. A clinical trial was conducted to evaluate its efficacy and safety. Methods: A 14-day, randomized, placebo-controlled, double blind, efficacy and safety study was conducted on 37 treated vs. 17 comparator (saline solution) patients suffering from dry cough. Products were applied as spray, 3-4 times daily, for maximum 14 days, and cough-related parameters were evaluated on days 1, 2, 3, 6, 9, 12, and 14. Results: Compared to the comparator product, test product triggered an instant and strong reduction in the mean scores of dry cough severity and frequency, and consequently in throat pain, irritation, swelling, and redness, with remarkable improvement in Leicester cough questionnaire parameters. Test product proved as safe as the comparator product. Conclusions: Cleaning the throat surface and fluidizing mucus using a new generation of liquid throat bandages opens new therapeutic horizons for the treatment of severe cough.

Objective: Wet cough is one of the most common pathologies in the world affecting nearly 12% of the world population. Being a multifactorial disease, involving initially viral infection, followed by bacterial secondary superinfection, damage to the throat mucosa, production of sticky mucus, and poor local immunity, there is currently no effective drug available. We conceived VB-Gy, an osmotically active filmogen solution, capable of cleaning the infected surface of all contaminants topically present, and of preparing a favorable ground for healing. The efficacy and safety of VB-Gy is assessed through a clinical trial, vs. saline solution as comparator product. Methods: The study was a multi-centric, randomized, placebo-controlled, double-blind trial on patients suffering from wet cough. The study involved 39 in the test product group and 15 patients in the comparator group, each patient applying 3-4 sprays of investigational product 4-5 times per day, over a maximum period of 15 days. The effects on wet cough severity, frequency, chest discomfort, as well as on throat pain, irritation, requirement for antibiotics, and answers to Leicester cough questionnaire for quality of life, were evaluated. Results: Although regular and frequent use of saline solution spray helped reduce wet cough symptoms noticeably, the test product induced very fast and nearly total regression of all clinical signs without any side effects, with statistically highly significant difference compared to placebo comparator and baseline data. Conclusion: Treating wet cough requires a multi-target, cell-friendly, and safe approach to obtain not only symptomatic but also curative relief. VB-Gy is a completely new generation of nearly instant, safe, and multi-target therapeutic approach of treating various topical infections.

Objective: Internal hemorrhoids are a widespread vascular disease for which currently there is no satisfactory curative treatment available. The pathology involves the disintegration of the supporting tissue of the anal cushions, causing venous dilation, blood stagnation in the hemorrhoid, formation of edematous venous plexus covered by mucosa, and inflammation. An effective treatment must therefore be multi-target and capable of acting on all the pathology parameters simultaneously. We evaluated the clinical efficacy of a topical, osmotically active filmogen medical device (VB-Gy-ip) directed at minimizing edema, inflammation and volume of the lesions, concomitantly. Methods: The study was a multi-centric, randomized, placebo-controlled, double-blind trial on patients suffering from internal hemorrhoids. 1 to 2 ml of test product, presented as a viscous solution containing VB-Gy-ip, presented in 50 ml tubes, was applied manually into the rectum, 3 to 4 times per day, for 14 consecutive days. Xanthan gum solution was used, in identical manner, as placebo or comparator product. The effects on the hemorrhoidal size, pain intensity, rectal bleeding, prolapse, defecation discomfort, irritation and itching were quantified using a 0 (no symptoms) to 10 (severe symptoms) scoring scale. Study design included 36 test product patients versus 18 placebo patients. Product safety and acceptability were also evaluated. All patients were re-examined on Day 21 to assess the eventual reversibility of the effects observed. Results: Although regular and frequent use of xanthan gum gel helped reduce internal hemorrhoid symptoms appreciably, the test product remarkably induced very fast and statistically significant regression of all the clinical signs without any side effects. Conclusion: An ideal treatment for internal hemorrhoid should simultaneously reduce edema, pain, inflammation, and the size of the lesion without any irritation or side effects. VB-Gy-ip is a completely new class of multi-target treatment for internal hemorrhoids, representing a big hope for millions of patients suffering from this pathology.

Objective: Allergic rhinitis (AR) is oversensitivity of nasal mucosa to allergen exposure leading to IgE-mediated nasal mucosal inflammation and cellular destruction. Applying any chemical drug over the nasal mucosa may provide symptomatic relief but at the same time the presence of chemicals, such as cortisones and antihistaminic, hampers mucosa repair and, in consequence, cellular defense functions. Therefore, cleaning, avoiding allergen exposure, and protecting nasal mucosa from contact with allergens with a cell-friendly mechanical device, could be an effective remedy to treat allergic rhinitis. Methods: A double blind, randomized, placebo controlled, multicenter clinical trial was conducted in patients suffering from severe AR. 15 patients were treated with saline as comparator product (CP) versus 31 treated with the test product (TP). The test product contained a natural gum-glycerol solution (VB-Gy) which was rendered filmogen using inert natural polymers (Allercyanidin-H) and termed as VB-Gy-Allercyanidin-H formula. The products (15 ml sprays) were applied topically over the nasal mucosa, 3-4 times a day over a period of 3 weeks. Total, reflective and instantaneous nasal symptom scores for rhinorrhea, nasal discharge, sneezing, and itching, as well as ocular scores (itching, tearing, redness) and rescue medicine use scores were evaluated daily during weeks -1 to +3 employing a 0 (no symptoms) to 3 (severe symptoms) scoring scale. Rhino-conjunctivitis quality of life (RQLQ) questionnaires were completed at the start and at the end of the study. Saline solution (CP) was used identically to the TP. Mean weekly results in CP and TP groups were compared with the scores at the start of treatment (baseline) and between the two groups. Results: CP was found to reduce only slightly the symptomatic manifestation of allergic rhinitis. The mean reduction compared to baseline at the end of weeks 1, 2, and 3 was respectively 11.7%, 13.6% and 15.1% for total nasal symptom scores (rTNSS); 9.9%, 14.5%, and 15.8% for total ocular symptom scores (rTOSS); and 4.97%, 8.45%, and 10.94% for pre-dose instantaneous total ocular symptom scores (am-iTOSS, p: Not Significant: NS). During the same period, compared to CP scores, the reduction in TP group was higher by 37.7%, 58.4%, and 73.5% for rTNSS; 38.3%, 54.6%, and 64.1% for rTOSS and 29.84%, 48.91%, and 59.77% for am-iTOSS (p

The present paper reports the thermoluminescence (TL) glow curve of Eu2+-activated SrAl2O4 phosphor with different UV exposure times. Evaluation of kinetic parameters was done by the peak shape method. The recorded glow curve shifts towards lower temperatures with respect to increasing UV exposure time. The peaks were found at 146.76, 141.34 and 140.37 °C, respectively, for 5, 10 and 15 min of UV exposure using the heating rate of 3°C s−1. The glow peak shows the second-order kinetics. Different kinetic parameters, i.e. trap depth, order of kinetics, activation energy, and frequency factor are also calculated. The XRD pattern of the sample is compared with reported XRD using the software match.

The present paper reports Thermoluminescence (TL) Glow curve of Mn2+ doped CaAl2O4 phosphor with different UV exposure time. The Glow peak shows general order kinetics and evaluation of kinetic parameters was done by peak shape method. Calculations of Trap Depth were done with Chen’s different methods and order of kinetics, activation energy and frequency factor are calculated. The recorded glow curve shifts towards higher temperature with increasing intensity as a function of UV exposure time until 30 minutes where it is seen that the peak shifts towards low temperature side and intensity also decreases. The peaks were found at 345?C, 356.83?C, 358?C and 356.73?C respectively using the heating rate 6.7?C/s. The PL (photoluminescence) excitation spectra show peaks at 248 nm and 362 nm whereas emission spectra shows peaks between 364 nm and 551 nm. Sample was characterized by XRD technique.