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In this study, the Yttrium Stabilized Zirconia (YSZ) thin films were deposited on the sapphire substrate (Al2O3) by dip-coating method using simple ethanol-based YSZ suspension. The layer thickness of YSZ films were varied by sintering at 1300°C. Phase change and structural evolution in YSZ films were observed by conducting X-ray diffraction (XRD) analyses. The microstructures and the surface morphology of the deposited films were examined using Atomic Force Microscope (AFM) and Field Emission Scanning Electron Microscope (FESEM). The XRD pattern revealed a phase change from cubic to monoclinic with an increase in YSZ layer thickness. The crystallite size was varied in the range of 9.68–42.98 nm with the changes in the layer thickness. Meanwhile, the AFM image analyses showed a layer thickness-dependent variation in the grain size (205.83–373.77 nm) and the RMS surface roughness (16.72–36.44 nm). The FESEM images of the achieved film exhibited the occurrence of a dense morphology. It was concluded that by controlling the layer thickness of the deposited films, their improved structure and morphology can be achieved.

The impact of low energy ions beam (700 keV A r 2 + and 300 keV H e 1 + ) irradiation on the modified structures, optical and photovoltaic attributes of the TiO2/TiO2-Graphene (TGr) thin films was reported for the first time. These TiO2/TGr thin films were deposited on the ITO substrate using the doctor blade method. The unexposed (pristine) and ions beam irradiated thin films were characterized using XRD, FE-SEM, UV–Vis spectroscopy and solar simulator to determine the interaction mechanism between the low energy ions beam and thin films useful for the perovskite solar cells. The XRD analyses of the TiO2/TGr thin films revealed an insignificant impact of the low energy ions beam irradiation, indicating an excellent structural stability of the grown films. The FESEM analyses of the irradiated thin films supported the XRD results, reaffirming an insignificant change in the particle size distribution. The figure of merit (FOM) of the low energy ions beam irradiated TGr thin films was amplified by a factor of 10 as obtained from the electrical conductivity measurement. It was shown that the stability and FOM of the TGr thin film can be improved via the low energy ions beam exposure, enabling it a better candidate as electron transport layer for the development of perovskite solar cells.

Europium-doped magnesium–zinc–sulfophosphate glasses of molar composition (65 − x) P2O5–20MgO–15ZnSO4–xEu2O3 (x = 0.0, 0.5, 1.0, 1.5 and 2.0) were prepared via melt-quenching method. The synthesized glasses were characterized at room temperature to determine the relationship between Racah and mechanical properties. The FTIR spectra of glasses in the range of 4000–400 cm−1 revealed the presence of characteristic functional groups. The Young’s, shear and bulk moduli of glasses were observed to enhance with the increase in Eu3+ contents. The ratio increased from 0.710 to 0.747 which confirms the increase in the degree of centrality of the glasses. Racah parameters evaluated from first three major absorption bands were reduced from 72.3906 to 60.1111 cm−1 with the increase in Europium contents, thus signifying the weakening in f–f electrons repulsion. Crystal field parameters decrease from 42.2445 to 35.2397 cm−1 denoting strong covalent character of ligand bond of the synthesized glass system. The synthesized glasses have potential for the development of hard surface engineering.

Magnesium-zinc-sulfophosphate glasses with various concentration of Silver nanoparticles (AgNPs) compose of 63.5P2O5–20MgO –15ZnSO4–1.5Eu2O3 –yAgNps (y = 0.0, 0.1, 0.3, 0.5, 0.7,0.9 and 1.1 g in excess) were prepared via melt-quenching method. As-Quenched glasses were then characterized to establish the relationship between optical and mechanical characteristics. Densities were found to increase from 3.0720 to 4.3304 g.cm-3 with increase in AgNPs embedding levels, suggesting the network shrinkages and enhanced compactness. The Young’s, shear and bulk modulus of glasses were observed to enhance with the increase in AgNPs contents. The Poisson’s ratio value increased from (0.0978 to 0.1416) while values of both Vickers hardness (from 0.0658 to 0. 0.0682 GPa) as well as (from 0.8350 to 0.8916) were increased. This necessitate the evaluation of ultrasonic properties and mechanical properties of the synthesized glasses and further analysed by various analytical tools. The studied glass may be useful for the development of hard surface engineering.

A series of Sm3+-doped magnesium borate glasses were prepared using the melt quenching and characterized to determine the effects of various Sm3+ contents on their optical traits. The absorption and luminescence spectra of the glasses revealed ten and four significant peaks, respectively. In addition, the experimental results on the optical properties were validated using the Judd-Ofelt (J−O) analyses. The obtained J−O intensity parameters (Ωλ with λ = 2, 4, 6) confirmed the structural changes in the host network due to the Sm3+ doping. The value of Ω2 for the studied glasses indicated the covalent and asymmetric nature of the Sm3+− O2 linkages. The achieved J−O radiative parameters (quality factor, branching ratio and stimulated emission cross-section) were highest for the glass made with 0.5 mol% of Sm3+, demonstrating its lasing potency. The proposed glass compositions may be beneficial for the photonic devices.

This paper reports the luminescence potential of the dysprosium ion (Dy3+)-doped (varying contents from 0.1 to 1.0 mol%) magnesium borate glasses prepared by the melt-quenching method. As-quenched samples were characterized systematically to determine the effects of various Dy3+ contents on their structure, physical and optical traits. The Judd−Ofelt (J−O) intensity parameters (Ω2, Ω4, Ω6) and radiative properties of the best sample (with 0.7 mol% of Dy3+ doping) was evaluated to complement the experimental optical data. The studied glasses revealed three luminescence emission peaks at 382 nm (4F9/2→6H15/2, intense Blue), 572 nm (4F9/2→6H15/2, intense Yellow) and 661 nm (4F9/2→6H11/2, weak Red) under the excitation wavelength of 347 nm. The emission intensity was first increased up to the Dy3+ content of 0.7 mol% and then quenched. The observed luminescence intensity quenching was due to the resonant energy transfer from the excited state to the neighbouring ground state of Dy3+. The obtained high value of Ω2 signified the strong degree of covalency between the Dy3+ and ligand environment. The optimum glass sample (with 0.7 mol% of Dy3+) showed higher values of the branching ratio and stimulated emission cross-cross section for the 4F9/2→6H15/2 (yellow) emission transition, indicating its potential as bright yellow luminescent material and high gain visible laser applications.

Some composites of barium ferrites activated with the neodymium ions (Nd3+) of composition (20)BaO:(80-x)γ-Fe2O3:(x)Nd2O3 (x = 0, 1 and 2 mol%) were synthesized using the modified mechanical alloying for the first time. The influence of varying Nd3+ concentrations on the morphologies, microstructures, and magnetic characteristics of these composites were evaluated. In addition, the microwave (MW) reflection loss, complex relative permittivity, and permeability of the studied composites in the frequency range of 8.2–12.4 GHz were analysed using the Nicholson-Ross-Weir (NRW) method. The inclusion of Nd3+ in the proposed composites was discerned to influence the permittivity, permeability and reflection loss significantly in the MW X-band region.

A series of bio-silica incorporated barium-ferrite-composites with the composition of (x)Bio-SiO2:(80-x)γ-Fe2O3:(20)BaO, where x = 0, 1, 2, and 3 wt% were prepared using the modified solid-state reaction method. The influence of different bio-silica (extricated from sintered rice husk) contents on the surface morphologies, structures, and magnetic characteristics of these composites were assessed. The relative complex permittivity and permeability were resolved using the Nicholson-Ross-Weir strategy in the frequency range of 8–13 GHz. Meanwhile, the reflection loss was estimated through the transmission/reflection line theory to assess the MW absorption properties of the composites. Incorporation of the bio-silica in the barium ferrite composites generated a new hexagonal phase (Ba3Fe32O51) and a tetragonal phase (BaFeSi4O10) which led to a decrease in the saturation magnetization and significant shift in the MW frequency absorption peak positions.

Enhancing the optical performance of rare earth doped binary inorganic glasses is an ever-demanding quest. Samarium (Sm3+) doped zinc tellurite glasses containing Manganese (Mn) nanoparticles (NPs) with composition (59-x)TeO2-20ZnCl2-10ZnO-10Li2O-1Sm2O3-(x)Mn3O4, where x = 0 to 0.06 mol% are prepared by melt quenching technique. The role played by Mn NPs in enhancing the optical behaviors are analyzed and discussed. The XRD patterns confirm the amorphous nature of the glass. The UV-Vis-NIR spectra reveal seven prominent absorption bands of Sm3+ ions. The photoluminescence spectra display four peaks corresponding to 4G5/2→6H5/2, 4G5/2 →6H7/2, 4G5/2→6H9/2 and 4G5/2 →6H11/2 transitions. An enhancement in the luminescence intensity is observed up to 0.05 mol% concentration of NPs and the intensity quenches beyond it. The enhancement is attributed to local electric field effect of NPs in the proximity of Sm3+ ion. Our results on improved optical response via precise control of NPs contents may be useful for the development of solid state lasers and amplifiers.

Customisation of the lasing characteristics of rare-earth ions activating various materials for practical applications requires fundamental knowledge of the structure and dielectric correlation. Based on these factors, a new series of glass ceramics of composition (40-x)P2O5 –30B2O3 –30ZnSO4 –xHo2O3 (x = 0.0, 0.4, 0.5, and 0.6 mol%) were prepared using the melt-quenching method. As-prepared samples were characterised using various techniques to determine the effect of holmium ion (Ho3+) doping on their structure and dielectric traits. XRD patterns of as-quenched samples confirmed their glass-ceramic characteristics. Holmium ion concentration-dependent Raman and FTIR analyses revealed the structural enhancement in the glass ceramics. The presence of Zn, S, B, P, O, and Ho in the glass ceramics was disclosed by the XPS spectra, and the ratio of the bridging to non-bridging oxygen atoms was evaluated by analysing the O1s peaks. The recorded room temperature complex impedance spectra of the samples in the range of 10 3 – 10 5 Hz were influenced by the predominant glassy and dormant crystalline structures. The UV–Vis–NIR data (in the range of 206–310 nm) and the impedance spectra (3 × 10 12 –3 × 10 14 nm) were analysed to evaluate the dielectric features of the samples. The considerable increase in the frequency-dependent AC conductivity and its slight reduction with Ho3+ incorporation was ascribed to the dopant ion-induced formation of quasi-molecular complexes (such as bridging oxygen and ligands) in the host network. A correlation between the structure and dielectric attributes of the titled glass ceramics was established. In short, the Ho3+-incorporated customised structures and dielectric properties of the newly proposed glass-ceramic composition were affirmed to be prospective for sundry applications.

Rare earth ions-doped oxide glasses with improved traits are needed for sundry applications. Based on this fact, physiochemical and magnetic characteristics of Er3+ -doped lead–tellurite glasses embedded with gold nanoshapes (Au-NSPs) were customized via preparation and characterization. Glasses of composition 78.95TeO2–15PbO–5PbCl2–1Er2O3–0.05AuCl3 were made using conventional melt-quenching techniques at varying (1, 6, 16, and 24 h) heat treatment durations (HTDs) to optimize their morphology, structure, chemical, and magnetic properties. Structure analysis verified the amorphous nature of the as-quenched samples and the homogeneous distribution of Au-NSPs within a network matrix with an average diameter ranged from 1.32 to 7.12 nm. Significant chemical functional groups of the glasses were detected at 360 and 598 cm‒1, attributed to the number of non-bridging oxygen (NBO) in glass and the conversion of TeO4 tbp into TeO3 polyhedra through TeO3+1. The magnetic behavior of the glasses was due to the diffusion-limited growth of Au-NSPs as evidenced from the ESR and VSM results. Saturation magnetization and magnetic coercivity were in the range of 4.61 × 10–2 to 10.614 × 102 emu/g) and 1441.60 to 1992.20 Oe, respectively. The variations of g-factor, resonant magnetic field, and peak-to-peak line-width of the glasses were established to be promising for various functional applications especially for biomedical devices as antiviral screen protectors.

The effects of silver nanoparticles (Ag NPs) embedment on the physical and structural characteristics of the holmium ions (Ho3+) activated phosphate-based glass-ceramics were assessed. Two series of such glass-ceramics were prepared using the melt-quenching and characterized. In the first series, the Ag NPs were nucleated from the incorporated AgCl via the redox process. In the second series, the pure Ag nanopowder was directly added. The overall properties of these glass-ceramics were strongly sensitive to the cooling procedure and NPs addition strategies, leading to different density and refractive index modifications in the two series. The recorded O1s XPS peaks were exploited to determine the bridging to non-bridging oxygen ratios in the studied glass-ceramics network that enabled to unfold the differences in the observed inferences. A compelling correlation among various attributes in the achieved glass-ceramics was established. Briefly, the overall traits of the proposed glass-ceramics were tailored by regulating the preparation conditions.

This article reports the influence of titania (TiO2) and TiO2-graphene (TGr) as electron transport layer (ETL) on the performance of polyethylene oxide (PEO) based perovskite solar cell (PSC). Compared to most commonly used ETLs, graphene based ETLs showed immense promise towards scalable fabrication and higher carrier injection of PSC. Driven by this idea, PEO layer was introduced in TiO2 and TGr based PSC to inspect the feasibility of achieving notably high fill factor. As-grown nanocomposites were analyzed using varied analytical tools to determine the effect of graphene inclusion on their morphology, optical and electrical properties. An increase in the absorption bandwidth and red-shift in the absorption peak was observed from UV-VIS spectra indicating band gap narrowing. By exploiting TGr nanocomposite in perovskite solar cells as electron collection layer, a remarkable fill factor of 44% has been achieved. In short, present disclosure may contribute towards the development of ETL in high performing PEO based perovskite solar cell (PSC).

Microwave (MW) frequency based wireless communications and electronic devices became prospective due to several ramifications. To meet this need, a series of neodymium ions (Nd3+) substituted barium ferrite composites with composition (20)BaO:(80–x)Fe2O3:(x)Nd2O3 (0 ≤ x ≤ 3 mol%) was prepared at 1100 °C using solid-state reaction method. We evaluated the effect of various Nd3+ ions contents on the surface morphology, structure, and magnetic properties of the as-synthesized barium ferrite composites. Meanwhile, microwave reflection loss, complex permittivity and permeability were determined using the transmission/reflection line method in the X-band (8–12 GHz). SEM image of the composites shows that the surface morphology consists of rough and porous microstructures. XRD patterns of the un-doped composites reveal the existence of BaFe12O19 (hexagonal) and Fe21.333O32 (tetragonal) crystalline phases. Furthermore, a new hexagonal crystalline phase of Ba6Nd2Fe4O15 with the crystallite sizes between 15 and 67 nm is observed due to Nd3+ ions substitution in the composite. The saturation magnetization of the composite containing 2 mol% of Nd3+ does not exhibit any significant alteration compared to the one devoid of Nd3+. The complex relative permitivity and permeability of the achieved composites enriched in Ba6Nd2Fe4O15 and BaFe2O4 phases disclose significant MW frequency dependence. The composites also display selective MW absorption in the X-band which could be useful for diverse applications.

The quest for optimized rare earth glass host is ever-increasing. Multi-component telluro-borate glass matrices are excellent rare earth host due to their unique spectroscopic traits. Inspired by this idea, a series of (70-y)B2O3–15BaSO4–15TeO2–ySm2O3 glasses were fabricated using melt-quenching method. The measured spectroscopic features were complemented by Judd–Ofelt (JO) analysis. The absorption spectra of as-quenched samples revealed nine bands in the ultraviolet–near-infrared regions. The photoluminescence (PL) emission spectra displayed four emission channels: moderate green, orange, moderate red, and a weak red emission of Sm3+ transitions. The observed quenching in the PL intensity of the glasses prepared with y > 1.0 mol% was attributed to the binary cross-relaxation mechanisms. The calculated JO intensity parameters Ω2, Ω4, and Ω6 were ranged from 1.48 to 4.20 (× 10−20 cm2), 2.31–4.31 (× 10−20 cm2) and 1.15–1.99 (× 10−20 cm2), respectively. Moreover, the small values of Ω2 disclosed the weak covalent nature of network co-ordination in the neighborhood of Sm3+ sites. The 4G5/2 to 6H7/2 transition of Sm3+ disclosed the highest branching ratio (68.8%), emission cross section (75.90 × 10−23 cm2), gain bandwidth (167.69 × 10−29 cm3), and optical gain (172.01 × 10−26 cm2 s−1) for BSTBSm0.5 glass. Briefly, the proposed glass composition may be a potential host for visible waveguide laser application.

We explored the feasibility of using Dy2O3 doped lithium magnesium borate (LMB) glass based thermoluminescence dosimeter (TLD) for high dose dosimetry in the range 1–100 Gy. Such glass system having composition (in mol%) of (70−z) B2O3–20Li2O–10MgO− zDy2O3 (where 0.05 ≤ z ≤ 0.7 mol%) were prepared via melt-quenching method and subsequently characterized. Radioactive cobalt (Co-60) source was used for irradiations. The optimum dysprosium (Dy3+) content, annealing characteristics, optimum heating rate, sensitivity, thermal fading, reproducibility, TL glow curve and dose response linearity were determined. XRD pattern confirmed the amorphous nature of the synthesized glasses. DTA analysis authenticated a good glass forming ability and thermal stability of the studied glasses. EDX spectra verified the precise elemental traces in the sample ead to determine the effective atomic number (Zeff) of the studied samples. The optimum pre-annealing temperature and time was correspondingly discerned to be 200 °C and 60 min. Furthermore, glass doped with 0.1 mol% of Dy2O3 revealed optimal TLD reading through simple glow curve with minimal fading, high sensitivity and good reproducibility, good linearity with linear regression coefficient of 0.999 and 0.996 in the dose range of 1–10 Gy and 10–100 Gy, respectively. In short, the achieved TLD was established to be a good candidate for accurate radiation detection in photon beam in the 1–100 Gy range.

Improvement of elastic and optical properties of rare earth ions doped glasses via the amalgamation of synthetic glass formers with natural mineral modifier became a new strategy to achieve novel glass based optical devices. Inspired by this idea, we prepared some new types of CeO2 doped boro-tellurite-dolomite (BTD) glasses of composition (35-x)B2O3–30TeO2-20Dp-15Dm-xCeO2 (where 0 ≤ x ≤ 2.0 mol%, Dm: dolomite marble and Dp: dolomite pebble) by standard melt-quenching method and characterized. The role of changing CeO2 concentration on the structural, elastic and optical traits of the proposed glasses was examined. Also, direct and indirect band gap energies, Urbach energies and refractive indices of glasses were evaluated using Tauc, absorption spectrum fitting (ASF) and derivation of absorption spectrum fitting (DASF) methods. Amorphous nature of the as-quenched samples was verified from XRD pattern and SEM image showed the homogeneous disordered surface. EDX spectra disclosed the right elemental traces in the prepared glasses. The N4 ratio calculated from the FTIR spectra revealed that the inclusion of CeO2 into the BTD network indeed favoured the conversion of BO3 to BO4 structural units. Besides, the ultrasonic velocities and elastic moduli were reduced with the increase in CeO2 contents. Complete absence of any peak in the optical absorption spectra validated the existence of Ce4+ within glasses. Moreover, the absorption coefficient of prepared glasses was significantly enhanced and the absorption edge was red shifted (from 400 nm to 500 nm) with the increase in CeO2 doping. Proposed glass compositions may be beneficial for future research and development on optical filter in photonic devices.

In the present work, three optically transparent tungsten niobate tellurite glasses with compositions of (90-x)TeO2-10Nb2O5-xWO3 (x = 0, 6, 12 mol%) were synthesized by conventional melt quenching technique. For all these three glass samples, the structural and the compositional dependence of different physical parameters such as density, molar volume and ionic packing density have been analyzed. It been observed that the amorphous nature of the samples has been confirm by X-ray diffraction analysis. The physical properties of the glasses were evaluated and the change in density ( ), molar volume ( ) and ionic packing density ( ) in these glasses indicates the effect of WO3 different content registered on the glasses structure. The highest refractive indexes value 2.171 at 632.8 nm was measured for 78TeO2–10Nb2O5–12WO3 glass. It is found that the addition of WO3 concentration to TeO2-Nb2O5 glass system increase the value of density, molar volume as well as ionic packing density. The refractive index value of the glass increase with tendency for small optical energy band gap.

Honey is a nutritious natural sweetener from honey bee-collected nectar from a variety of flowers. The health benefits and high value of honey, however, have motivated fraudulent acts of honey adulteration by either a direct or secondary inclusion of cheaper sweeteners. Therefore, stringent quality controls must be in place to ensure authenticity of honeys while safeguarding the wellbeing of consumers. To detect adulterants in honey, researchers are continually exploring rapid, sensitive and efficient recognition systems using chemometric-integrated spectroscopic techniques. These techniques have garnered significant attention of researchers for use in categorizing and detecting honey, as well as the incorporated adulterants. This paper provides an all-inclusive overview on the challenges for effective detection and quantification of a wide-ranging sugary adulterants in honey, worldwide. The advantages and drawbacks of diversified analytical techniques including nuclear magnetic resonance spectroscopy, infrared and Raman spectroscopy, sensor-based methods and chromatography with different sample pre-treatments for distinguishing the adulterants in honey are also discussed. This article also compares and deliberates on the performance among the reported techniques to detect adulterants in honey, specifically highlighting the concepts used for detection, along with the modifications that were made which led to their success and failure.

Detector efficiency calibration is mandatory for accurate measurement of induced activity in irradiated samples and for safe operation of the reactor with minimal uncertainty. This paper reported the efficiency calibration of vertically dIpstick High Purity Germanium detector, installed at the Centre for Energy Research and Training, Ahmadu Bello University Zaria for the purpose of large sample Neutron Activation Analysis (NAA) using Nigeria research reactor-1 (NIRR-1). The performance of the detector was evaluated for the radioisotope activity measurements during the reactor operation for large samples neutron activation analysis. The detector performance in terms of radioisotopes detection ability was inspected using the standard conventional and semi-empirical approaches. The full energy peak efficiencies were determined at the corresponding energies for three different geometries (source to detector distance of 1, 5 and 10 cm). The semi-empirical approach produced better and precise results that logically rhymed with theory than the traditional approach. Besides that, a consistency in the nature of the graphs and values were evidenced. The determined efficiencies and their corresponding energies revealed encouraging outcome and ensured the successful NAA for large samples of different material compositions.

Long exposure to radiation from fluoroscopy-guided interventions (FGIs) can be detrimental to both patients and radiologists. The effective doses received by the interventional radiology staff after performing 230 FGIs in a year were assessed by using double dosimetry and five various algorithms. The Shapiro–Wilk test revealed normally-distributed data (p < 0.01), while the significant correlation coefficients between the effective doses ranged between 0.88 and 1.00. As for the Bland–Altman analysis, both Niklason and Boetticher algorithms strongly supported the absence of statistical significance between the estimated effective doses. This portrays that the occupational doses received by the interventional radiology staff during FGIs fall within the acceptable limit regardless of the varied algorithms applied. In short, the Niklason and Boetticher algorithms appeared to be the more interchangeable ones for effective evaluation of doses. This is in view of their strong mutual correlations and excellent agreement.

Erbium ions (Er3+) doped zinc phosphate glass system with varying contents of natural ferrite (Fe3O4) nanoparticles were prepared using melt quenching method. The glass is characterized by x-ray diffraction (XRD) and UV-VIS NIR spectrometer. It is observed that the amorphous nature of the glass is confirmed by x-ray diffraction. The absorption spectra of the glass are recorded in the UV-Visible in the range of 400-1600 nm. The UV-VIS NIR spectra reveal ten absorption peaks centered at 376, 406, 420, 486, 522, 546, 652, 798, 976 and 1534 nm, correspond to the transitions from the ground state 4I15/2 to higher 4I13/2, 4I11/2, 4I9/2, 4F9/2, 4S3/2, 2H11/2, 4F7/2, 4F3/2, 2H9/2, 4G11/2 levels, respectively. Effects of natural ferrite oxide nanoparticles on the absorption and emission properties of the synthesized glasses were analyzed via Judd-Ofelt (J-O) theory. The J-O intensity-parameters (W2, W4, W6) analysis demonstrate a significant increase of spectroscopic quality factors.Keywords: Fe3O4 NPs, Absorption, Judd-Ofelt.

We used inductively coupled plasma-optical emission spectrometry (ICP-OES) and laser-induced breakdown spectroscopy (LIBS) united partial least square regression (PLSR) with reference to ICP-OES outcome for the evaluation of Ca, Mg and Na contents in 30 stingless bees’ honeys. The PLSR calibration models were constructed using 25 honeys. Coefficient of determinations (standard error of cross validation) for the calibration and the cross validation assessments of the three individual PLSR models targeted in favour of Ca, Mg and Na were respectively over 0.923 (25.6 mg/kg), 0.950 (15.1 mg/kg), and 0.909 (30.5 mg/kg). Five independent samples were used as validation dataset for testing the legitimacy and repeatability of the proposed strategy. Constructed models predicted the concentrations of Ca, Mg and Na with corresponding averaged percentage errors (relative standard deviations) of 6.71% (4.56%), 27.22% (6.14%) and 6.48% (5.47%). The proposed strategy was shown to be efficient for the stingless bees’ honeys elemental compositions analyses.

Numerous studies have shown the interesting properties of trivalent lanthanide ions when doped in different types of glasses. This article examines the physical, structural and optical properties of series of strontium magnesium borate glasses doped with dysprosium ion (Dy3+) and synthesized using the melt-quenching technique. Physical and optical properties such as density, molar volume, ion concentration, molar refractivity, polaron radius, reflection loss, inter-nuclear distance and molar polarizability for each concentration of the dopant were calculated and reported. The results revealed diverse variations in density with other measured parameters. The amorphous behaviour of the glass samples was confirmed by X-ray diffraction spectroscopy. FTIR spectra measurements revealed the presence of various functional groups and their associated assignments. Optical properties of the activated glass samples with different concentrations of Dy3+ were determined by measuring the absorption and luminescence spectra in the visible region. The UV–Vis–NIR spectrophotometer analysis indicated the presence of eight inhomogeneous transition bands in various positions and intensities with hypersensitive transition at 1260 nm (6H15/2 → 6F11/2). The experimental oscillator strength (fexp) for each calculated absorption band showed higher magnitudes at hypersensitive transition. The optical energy band gap in the current work showed a decrease in values with increasing ion concentrations. The luminescence spectra of the prepared glass phosphors showed three unique transitions at 4F9/2 → 6H15/2 (490 nm), 4F9/2 → 6H13/2 (585 nm) and 4F9/2 → 6H11/2 (689 nm).

The new-fangled outbreak of the coronavirus (CoV) has carried consideration to an old viral enemy since December 2019. This has generated higher anxieties towards the present protection measures and medical facilities to grip such a risk. Wuhan-originated nCoV has appeared as a global public health emergency. CoV causes diarrhoea and upper respiratory diseases in animals, with an incubation period of 2–14 days. It is transmitted by the droplets of cough or sneeze from infected persons. Thus, people are directed to elude community places and near contact with the infected peoples (so-called quarantine). Repeated washing of hands, social distancing, and not touching anything (people, face, or frequently used surfaces) are taken as the key measures to fight against this deadly virus. Currently, the vaccine for COVID-19 is not developed. This chapter abridges the emerging evidence for understanding the virion structure of CoV, epidemiology of COVID-19, its diagnosis, prevention of the transmission, and treatment using nanotechnology. The main erudition facts from the continuing efforts to prevent this pandemic besides the necessity to capitalize in the health schemes are summarized.

Ascertaining plasmonic interaction induced by silver (Ag) and gold (Au) nanoparticles (NPs) in the amorphous system can open a new direction in photonics. In this outlook, various contents of Ag and Au NPs were incorporated into neodymium ions (Nd3+)-doped zinc-sulfate-magnesium-phosphate glasses via the melt-quenching method. The impact of Ag–Au plasmonic coupling on the structures and spectroscopic traits of the prepared glasses were evaluated. As-quenched samples were analyzed using XRD, HRTEM, Raman, absorption and photoluminescence (PL) spectrometer. The Judd-Ofelt (JO) theory was used to evaluate the spectroscopic quality and stimulated emission cross-section of the glasses. HRTEM micrographs verified the existence of Au and Ag NPs in the glass matrix with a mean size ranged 4.47–7.03 nm. The observed thirteen absorption bands centered around 326, 352, 430, 459, 473, 512, 52, 581, 627, 681, 744, 801, and 875 nm were corresponding to electronic transitions from the ground state (4I9/2) to the excited states of 4D7/2, 2D1/2+4D3/2+4D5/2, 2P1/2, 4G11/2, 2D3/2+2P3/2+2G9/2, 4G9/2+2K13/2, 4G7/2, 4G5/2+2G7/2, 2H11/2, 4F9/2, 4F7/2+4S3/2, 4F5/2+2H9/2 and 4F3/2 in Nd3+. Two surface plasmon resonance (SPR) bands assigned to Ag and Au NPs were probed at 442 nm and 503 nm. The addition of Au NPs causes the SPR band of Ag NPs to be red-shifted. The NIR PL bands at 878 nm, 1050 nm and 1322 nm were due to the 4F3/2 → 4I9/2, 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 transitions, respectively. The PMZ1.5Nd0.5Ag0·1Au glass disclosed the highest bandwidth gain of 6.92, 17.05 and 9.10 ( × 10−23 cm3) corresponding to the 4F3/2 → 4I9/2, 4F3/2 → 4I11/2 and 4F3/2 → 4I13/2 transitions. It was shown that the PL intensity of the studied glasses could be modified by varying Ag and Au NPs contents. The Ag–Au NPs plasmonic coupling inclusion inside the glass can be beneficial to develop versatile optical materials.

Gold (Au) nanoparticles (NPs) incorporated in magnesium zinc sulfo-phosphate glass with the molar composition of (58.5P_2O_5–20MgO–20ZnSO_4–1.5Nd_2O_3–xAu NPs (where x = 0.0, 0.1, 0.2, 0.3, and 0.4 mol%) were prepared via melt quench technique. The effect of Au NPs as incorporated in Nd^3+ doped glasses were studied using X‒ray diffraction (XRD), High Resolution-Transmission Electron Microscope (HR‒TEM), UV‒Visible-NIR absorption spectrometer and photoluminescence spectrometer. The amorphous nature of glass is confirmed via XRD measurements and existence of Au NPs inside the glass is reveal by HR-EM. The typical absorption bands of Nd^3+ are attained which positioned around 352, 430, 459, 474, 512, 525, 581, 626, 682, 744, 801and 875 nm. Up-conversion (UC) photoluminescence (PL) demonstrated six prominent emission bands located around 420, 445, 460, 484, 515 and 545 nm corresponding transition 2P_1/2--> 4I_9/2, 2D_5/2-->4I_11/2, 2P_1/2-->4I_11/2, 2D_5/2-->4I_13/2, 2K_15/2,4G_7/2-->4I_11/2,4I_9/2 and 2D_5/2-->4I_15/2 respectively. Glass containing 0.1 mol% of Au NPs shows utmost PL enhancement and the emission decrease beyond 0.1 mol% of Au NPs depicts re-absorption of SPR and increase of non-radiative channel. The improvement of PL intensity attributed to local field effect of Au NPs that altered the environment in proximity Nd^3+ ions. The proposed glass could be potential for improvement of solid state laser design.

Presence of rich bioactive compounds (polyphenol, cinnamaldehyde and flavanols) in cinnamon make them greatly beneficial for biomedicinal and food applications. Considering such prospects, we prepared decahedral cinnamon nanoparticles (DCNPs) in pure honey via pulse laser ablation in liquid (PLAL) technique at varied laser ablation energy (LAE, 0–180 mJ) and characterized. LAE dependent structure and morphology of such DCNPs were determined. DCNPs grown at LAE of 90 mJ manifested the best size distribution with average diameter of 17.08 ± 4.71 nm. Furthermore, bactericidal traits of these DCNPs against Escherichia coli (EC) and Bacillus subtilis (BS) bacterial strains were assessed using agar well diffusion and optical density analyses. The DCNPs assisted inhibition zone diameter-antibiotic tested against such bacterial strains was remarkably enlarged. The proposed DCNPs were shown to be effective for the development of future nanomedicine.

Effects of silver (Ag) nanoparticles (NPs) on the physical and optical properties of erbium ions (Er3+) doped magnesium zinc sulfophosphate glasses of composition (59.5-x)P2O5-20.0MgO-20.0ZnSO4-0.5Er2O3-xAgCl (where x ≤ 1.5 mol%) were examined. Transparent bubble free glasses were prepared using melt quenching method. As-quenched samples were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), ultraviolet-visible (UV–Vis) absorption and photoluminescence (PL) spectroscopy to determine the feasibility of achieving their improved optical properties useful for photonic devices. Furthermore, Judd-Ofelt intensity and radiative parameters were evaluated to complement the experimental observations. XRD patterns of as-quenched samples confirmed their amorphous nature. TEM images of glasses revealed the nucleation of Ag NPs with average size of 10 nm. UV–Vis spectra of glasses exhibited nine absorption bands assigned to 4f-4f transitions of Er3+ ions. An enhancement in the PL emission intensities corresponding to the 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions by a factor of 6 and 5 were achieved. Such enhancement was attributed to the local field effect (LFE) stimulated by the surface plasmon resonance (SPR) of Ag NPs alongside energy transfer mechanism among Er3+ ions and Ag NPs.

We report the influence of silver (Ag) and titania (TiO2) nanoparticles (ATNPs) co-embedment on the photoluminescence (PL) properties of dysprosium ions (Dy3+) doped zinc-magnesium tellurite glass system prepared using conventional melt quenching method. Both up- and down- converted PL spectra of glasses revealed three emission bands located at 482 (blue: 4F9/2 → 6H15/2), 574 (yellow: 4F9/2 → 6H13/2) and 664 nm (weak red: 4F9/2 → 6H11/2), where the band intensities were enhanced with the inclusion of ATNPs. Glasses with 0.2 mol% of ANPs and up to 0.3 mol% of TNPs disclosed highest PL intensity enhancement, which was majorly attributed to the ATNPs mediated localized surface plasmon resonance (LSPR) and large field enhancement (called hot spot) effects in the proximity of Dy3+ ions. Absorption spectra of glasses displayed two plasmon bands characteristics of each type of nanoparticle. It was inferred that the superposition of localized SP modes from ATNPs could generate new hybridized modes (strong local field in the vicinity of Dy3+ ions) shifted with respect to the single type of NPs resonance. HRTEM images showed the existence of both Ag and titania NPs inside the glass matrix. Glasses containing ATNPs exhibited anatase phase with (103) and (112) nanocrystalline lattice plane orientation. Proposed glass system may be useful for the development of solid state laser and photonic devices.

Intense visible emissions from dysprosium (Dy3+) ions doped glasses became prospective for diverse technological applications. In this paper, physical, optical and structural properties of magnesium borate glasses doped with varied concentrations of Dy2O3 were examined. Such glasses were synthesised by melt quenching method and characterized at room temperature using several analytical techniques. Luminescence and absorption spectra (in the visible region) of as-quenched samples were used to evaluate the physical and optical properties. XRD pattern confims the amorphous state of as-quenched samples. The Fourier transform infrared (FTIR) spectra of glasses reveal various bonding vibrations assigned to different functional groups. UV-vis-NIR spectra disclose eight absorption bands accompanied by a band for hypersensitive transition positioned at 1260 nm (6H15/2 → 6F11/2). The values of direct and indirect optical energy band gap of the studied glasses are decreased with the increase of Dy3+ ion contents. The photoluminescence spectra of all glasses under the excitation of 380 nm display two prominent emission bands centred at 497 nm (4F9/2 → 6H15/2, blue) and 587 nm (4F9/2 → 6H13/2, green). The achieved intense luminescence from the proposed glass composition may be beneficial for solid-state laser applications.

In defining the finiteness or infiniteness conditions of discrete spectrum of the Schrodinger operators, a fundamental understanding on $$n(1, F(\cdot ))$$ is crucial, where n(1, F) is the number of eigenvalues of the Fredholm operator F to the right of 1. Driven by this idea, this paper provided the invertibility condition for some class of operators. A sufficient condition for finiteness of the discrete spectrum involving the self-adjoint operator acting on Hilbert space was achieved. A relation was established between the eigenvalue 1 of the self-adjoint Fredholm operator valued function $$F(\cdot )$$ defined in the interval of (a, b) and discontinuous points of the function $$n(1, F(\cdot ))$$ . Besides, the obtained relation allowed us to define the finiteness of the numbers $$z\in (a,b)$$ for which 1 is an eigenvalue of F(z) even if $$F(\cdot )$$ is not defined at a and b. Results were validated through some examples.

Considering the biomedical and biocatalytic effectiveness of cinnamon nanoparticles (CNPs), we prepared them in methanol media using green pulsed laser ablation in liquid (PLAL) technique. A Q-switched pulsed Nd:YAG laser of wavelength 532 nm was used. These colloidal CNPs were characterized at room temperature using TEM, EDX, UV–Vis absorption, PL emission and FTIR-ATR measurements. The influence of varying laser ablation energy (LAE) on the structure, morphology and optical properties were determined. TEM images manifested the nucleation of highly spherical (mean diameter 19.43 nm), stable and pure CNPs with excellent absorption and emission behavior. EDX spectra divulged the appropriate elemental traces in the CNPs. Absorption spectra of CNPs revealed an intense UV peak centered at 321 nm. FTIR-ATR spectra disclosed the covering of CNPs by plant secondary metabolites and released protein molecule. PL emission spectra of as-synthesized CNPs under 350 nm excitations displayed a prominent peak in the range of 436–431 nm accompanied by a blue shift with increasing LAE. Furthermore, the PL intensity was gradually enhanced with the increase in LAE, demonstrating the formation of large number of luminescent centers by CNPs. Such distinctive features of CNPs were attributed to the synergy between methanol as liquid growth media and fundamental wavelength of laser. It was established that the achieved spherical CNPs in methanol suspension could be beneficial for antioxidant purposes.

Glasses with composition (59.5-x)P2O5–20.0MgO-20.0ZnSO4–0.5Dy2O3-xAgCl (0.0≤x≤ 0.5 mol%) were prepared by melt-quenching method and characterized thoroughly. The role of silver nanoparticles (Ag NPs) inclusion on the spectroscopic and the physical properties of the synthesized glasses were determined. Judd-Ofelt (J-O) theory was used to complement the experimental optical data. TEM images confirmed the existence of Ag NPs of average size ≈4.5 nm. The absorption spectra showed eleven bands aroused from the ground state (6I15/2) to various excited states transitions of dysprosium (Dy3+) ion. The surface plasmon resonance (SPR) peak of Ag NPs was probed around 446 nm. The calculated J-O parameter (Ω2) for the glass without Ag NPs incorporation was the highest, indicating the strong metal-ligand covalence bond. Irrespective of Ag NPs contents, the emission spectra of the studied glasses revealed two intense photoluminescence bands centered at 480 nm (blue: 4F9/2→6H15/2) and 574 nm (yellow: 4F9/2→6H13/2) accompanied by two very weak red bands positioned at 662 and 752 nm. The luminescence intensity of both blue and yellow band was enhanced by a factor of 2 and it was 1.5 fold for the red bands. This enrichment in the luminescence intensity was attributed to the Ag NPs mediated SPR effect and subsequent energy transfer from the Ag NPs to the nearsighted Dy3+ ions.

The current paper illustrates glow curve analysis of newly developed Borate glass dosimeters. A series of dosimetric properties including dose response for photons and electrons, energy response, optical fading, and precision were determined. Glow curve deconvolution based on the general order kinetics equation was applied to extract the trapping parameters. Excellent fitting was obtained with the superposition of three-second order glow peaks. The quality of fitting was monitored through the r2 value which is always in excess of 0.9998. Thermoluminescence (TL) measurements showed that the material exhibits good linear dose–response over the delivered range of absorbed dose from 0.5 to 4 Gy for photons and electrons irradiation with low energy dependence. The material exhibits large signal loss when exposed to direct sunlight and moderate signal loss when exposed to fluorescent light. Therefore, it is recommended to use the current dosimeters indoor and to avoid prolonged direct exposure to fluorescent light. This combination of properties makes the material suitable for radiation dosimetry. Keywords: Dosimeter, Analysis, Boron

Nanobioceramics with enhanced mechanical and degradable properties are demanding for bone tissue engineering purposes. We report the influence of partial replacement of ZnO by tricalcium phosphate (TCP) on the improved structure, degradation and mechanical properties of sol-gel grown MgO-ZnO-TCP nanobioceramics. Sample containing 40 mol% of TCP revealed homogenous distribution of fine agglomerates composed of ellipsoidal plates-like particles of average diameter ≈25.42 nm and length ≈80.93 nm. Immersion test is performed to determine the degradation characteristics of the as-prepared samples. Sample containing 40 mol% of TCP presented the lowest degradation rate and delayed loss of the compressive strength. It is established that the proposed MgO-ZnO-TCP nanobioceramic composition with good mechanical properties and corrosion resistance are prospective for biodegradable implants.

Basic understanding on the spectroscopic behaviour of holmium ion (Ho3+) doped in magnesium zinc sulfophosphate glass host is essential for the development of inexpensive and eye–safe infrared solid state laser. To achieve this goal, six such glass samples were prepared using melt quenching method at varying Ho3+ ions contents. FTIR and Raman spectra were recorded to determine the structural properties of the synthesized glasses. Samples were characterized using UV–Vis–NIR absorption and photoluminescence (PL) spectroscopy to determine the Ho3+ ions concentration dependent spectral properties. The absorption spectra of the studied glasses revealed seven peaks which were allocated to the transition from the ground state (5I8) to the excited states (3H6, 5G5, 5G6, 3K8, 5F3, 5F4+5S2, 5F5, 5I6, and 5I7) of Ho3+ ion. Judd–Ofelt (J–O) intensity parameters (Ω2, Ω4, and Ω6) and radiative parameters such as transition probabilities, fluorescence branching ratio, and radiative lifetime were calculated from the measured optical spectra. The nephelauxetic ratio shows negative value signifying ionic bond between REI and the ligand. The value of J–O parameters Ω2, Ω4, Ω6 and spectroscopic quality factor were varied in the range of (4.10 − 8.05) ×10−20 cm2, (1.96−2.77) ×10−20 cm2, (1.95−2.31) ×10−20 cm2 and (1.01 − 1.25), respectively. The small of Ω2 indicated high symmetry around Ho3+ ions while the large value of Ω4 and Ω6 signified the occurrence of high rigidity of the glasses. PL emission spectra of the synthesized glasses disclosed two significant bands assigned to 5F4 → 5I8 (green) and 5F5 → 5I8 (red) transitions. The stimulated emission cross–section for the green and red luminescence was ranged respectively between (8.60 − 10.79) ×10−21 cm2 and (9.35 − 11.62) ×10−21 cm2. The proposed glasses was established to be beneficial for solid state laser application.

Silver (Ag) and Titania (TiO2) nanoparticles (ATNPs) co−embedded and dysprosium (Dy3+) ions doped magnesium−zinc−tellurite glasses were synthesized via melt quenching method. As−prepared samples were characterized using various analytical tools. Nanoparticles concentration dependent spectroscopic properties of the prepared glasses were evaluated using Judd−Ofelt (J−O) analysis. XRD pattern verified the amorphous nature of as−quenched samples. The UV–Vis spectra revealed six absorption bands centred at 1690, 1283, 1097, 904, 800 and 755 nm, assigned to the transitions from the ground level to different excited levels of Dy3+ ions. The photoluminescence (PL) emission spectra of the glass system displayed three emission bands positioned at 482 (blue: 4F9/2 → 6H15/2), 574 (yellow: 4F9/2 → 6H13/2) and 664 nm (weak red: 4F9/2 → 6H11/2). For all the bands, the PL intensities of the studied glasses were more pronounced than singly embedded sample (either ANPs or TNPs). Furthermore, the enhancement in the PL peak intensity due to the inclusion of metallic NPs was attributed to the surface plasmon resonance mediated local field effect in the proximity of Dy3+ ions. Ligand bonding of Dy3+ showed the ionic nature of the prepared glasses. The absorption and emission spectral data were used to evaluate the J−O intensity parameters (Ωλ (λ = 2, 4, 6)) and radiative properties. Values of Ωλ (λ = 2, 4, 6) for glass with 0.1 mol% of TNPs exhibited the trend of Ω2>Ω6>Ω4 while all other glasses revealed Ω2>Ω4>Ω6. It was demonstrated that by combining two types of NPs (Ag and TiO2) hot spot with intense electromagnetic field could be created in the neighbourhood of Dy3+ ion to achieve enhanced optical attributes of the proposed glasses. The attainment of large quality factors and quantum efficiency (≈100%) in the ATNPs co−embedded glasses were established to be beneficial for the development of solid state lasers and other photonic devices.

To minimize the signal degradation, many electronic devices require efficient microwave absorbers with very low reflection-losses within the X-band. We prepared a series of trivalent neodymium-ion (Nd 3+ ) substituted barium-natural ferrite using a modified solid-state reaction method. The effect of the Nd 3+ -ion content on the structure, surface morphology, magnetic properties, and microwave reflection loss was studied. The composites were characterized using X-ray diffraction, a vibrating sample magnetometer, scanning electron microscopy, and a vector network analyzer. The XRD patterns of the sample without Nd 3+ reveal the presence of BaFe 12 O 19 (hexagonal) and BaFe 2 O 4 (rhombohedral) phases. Furthermore, a new hexagonal crystal phase of Ba 6 Nd 2 Fe 4 O 15 appeared after substituting Nd 3+ . The average size of the prepared barium-natural ferrite particles was estimated to be between 0.4 and 0.8 μm. Both saturation magnetization and microwave reflection losses of these barium-ferrites were significantly reduced by increasing the Nd 3+ content.

We report the ubiquitous radiographic characteristics of optically stimulated luminescence dosimeters (OSLD) so called nanoDot OSLDs (Landauer Inc., Glendwood, IL). The X-ray irradiations were performed in free air ambiance to inspect the repeatability, the reproducibility, the signal depletion, the element correction factors (ECFs), the dose response and the energy dependence. Repeatability of multiple readouts after single irradiation to 10 mGy revealed a coefficient of variation below 3%, while the reproducibility in repeated irradiation-readout-annealing cycles was above 2%. The OSL signal depletion for three nanoDots with simultaneous irradiation to 20 mGy and sequential readouts of 25 times displayed a consistent signal reduction ≈0.5% per readout with R2 values over 0.98. ECFs for individual OSLDs were varied from 0.97 to 1.03. In the entire dose range under 80 kV, a good linearity with an R2 exceeding 0.99 was achieved. Besides, the percentage difference between OSLD and ion-chamber dose was less than 5%, which was superior to TLD. The X-ray photon irradiated energy response factors (between 0.76 and 1.12) in the range of 40–150 kV (26.1–61.2 keV) exhibited significant energy dependence. Indeed, the nanoDot OSLDs disclosed good repeatability, reproducibility and linearity. The OSLDs measured doses were closer to ion-chamber doses than that of TLD. It can be further improved up to ≈3% by applying the individual dosimeter ECF. On top, the energy dependent uncertainties can be minimized using the energy correction factors. It is established that the studied nanoDot OSLDs are prospective for measuring entrance dose in general radiographic practices.

The performance of optically stimulated luminescence dosimeters (OSLDs, Al2O3:C) was evaluated in terms of the operational quantity of HP(10) in Co-60 external beam teletherapy unit. The reproducibility, signal depletion, and dose linearity of each dosimeter was investigated. For ten repeated readouts, each dosimeter exposed to 50mSv was found to be reproducible below 1.9 ± 3% from the mean value, indicating good reader stability. Meanwhile, an average signal reduction of 0.5% per readout was found. The dose response revealed a good linearity within the dose range of 5-50mSv having nearly perfect regression line with R2 equals 0.9992. The accuracy of the measured doses were evaluated in terms of operational quantity HP(10), wherein the trumpet curve method was used respecting the 1990 International Commission on Radiological Protection (ICRP) standard. The accuracy of the overall measurements from all dosimeters was discerned to be within the trumpet curve and devoid of outlier. It is established that the achieved OSL Al2O3:C dosimeters are greatly reliable for equivalent dose assessment.

Efficient up-converted lasing materials are required for high performing, durable and low cost photonic devices. Rare earth ions doped glass systems with modified optical properties may meet this need. In this view, erbium (Er3+) ions doped zinc-magnesium-tellurite glass system of composition (75-x)TeO2–15ZnO–10MgO–xEr2O3 (0.5 ≤ x ≤ 2.0 mol%) was prepared via melt-quenching method. Optical behavior of such glasses was determined as a function of changing Er2O3 content to examine the feasibility of achieving up-converted lasing media. Judd-Ofelt (J-O) intensity (Ω2, Ω4, Ω6) and radiative parameters were evaluated. Glass hardness was increased linearly with increasing Er3+ ions concentration. The emission spectra revealed three peaks around 470 nm, 500 nm and 550 nm. Effect of Er2O3 content on the 4I13/2 → 4I15/2 transition was quantified in terms of fluorescence intensity and lifetime. The width of the near-infrared fluorescence band (1.53 μm) was broadened from 58.77 to 60.01 nm with the increase of Er2O3 content from 0.5 to 2.0 mol%. The proposed glass compositions were demonstrated to be potential for solid-state lasers, near infrared sensors, and other optical devices.