Littérature scientifique sur le sujet « Ultraviolet spectra, Photons, X-ray diffraction »
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Articles de revues sur le sujet "Ultraviolet spectra, Photons, X-ray diffraction"
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Fu, Chang Feng, Lian Fu Han, Chao Liu et Xi Ming Chen. « Structural and Optical Properties of Zn1-XCrXO Thin Films Deposited by Magnetron Sputtering ». Materials Science Forum 687 (juin 2011) : 750–55. http://dx.doi.org/10.4028/www.scientific.net/msf.687.750.
Texte intégralRésumé :
In this study, Zn1-xCrxO thin films were successfully fabricated on glass substrates by magnetron sputtering technique. The relationship between Cr doping concentration and the structural and optical characteristics of the produced samples was investigated by X-ray diffraction (XRD), optical transmittance and photoluminescence(PL). EDS results demonstrate that Cr ions are substitutionally incorporated into ZnO. XRD analysis reveals that all the prepared films with a preferential c-axis orientation exhibit the wurtzite structure of ZnO. The spectrometer transmittance data indicates that the band gap energies of the Zn1-xCrxO films are calculated by a linear fitting method. The band gap is found to be large with the increasing dopant concentration. The PL spectra suggest that all the samples have an ultraviolet emission peak centered at 370 nm. With the improved Cr-doped concentration, the peaks of ultraviolet emission have a blue shift to the region of higher photon energy, which is coincident with those values calculated by the linear fitting from the transmittance data. It is also found that the intensity of ultraviolet emission has been remarkably improved when Cr content is approximately 2.0at.%, but it is decreased when doping concentration of Cr is excessively high.
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Bulus, I., J. K. Sheyin, E. Yayock et A. S. Dalhatu. « Nd3+ CONCENTRATION DEPENDENT OPTICAL FEATURES OF GADOLINIUM BOROPHOSPHO-TELLURITE GLASSES ». Open Journal of Physical Science (ISSN : 2734-2123) 1, no 1 (10 mars 2020) : 1–10. http://dx.doi.org/10.52417/ojps.v1i1.84.
Texte intégralRésumé :
Improving the optical response of glass host with two or more strong network formers via suitable controlled of rare earth ions is the key issue in the fabrication of optical based glass for solid state lasers and light emitting devices. Hence, we report the Nd3+ concentration dependent on optical parameters such as absorption edge, optical band gap (direct and indirect) and Urbach’s energy of gadolinium borophospho-tellurite glasses with chemical composition of 10Gd2O + 30B2O3 + 20P2O5 + (40-)TeO2 + Nd2O3 (where 0.0 ≤ x ≤ 1.0 mol%). The glass samples were synthesized by convectional melt quenching method and characterized through X-Ray Diffraction (XRD) and Ultraviolet Visible Near-Infrared (UV-Vis-NIR) measurements. The amorphous nature of these glasses was confirmed by X-Ray diffraction pattern while the UV-Vis-NIR spectra revealed six absorption peaks corresponding to the transition from ground level 4I9/2 to the various excited state of Nd3+ ions. It was found that the investigated range of Nd3+ doping concentrations has a great influence on aforementioned parameters. The excellent optical features established in the present glass host suggest their potentiality for solid-state lasers and other photonic applications.
Bulus, I. | Department of Physics, School of Sciences, Kaduna State College of Education Gidan waya, Kafanchan, Nigeria
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Talib, A., M. K. Ahmad, N. Ahmad, N. Nafarizal, F. Mohamad, C. F. Soon, A. B. Suriani, M. H.Mamat, K. Murakami et M. Shimomura. « Optimum Reduced Graphene Oxide (rGO) Volume for Hydrothermal Synthesis of Titanium Dioxide (TiO2) Nanostructure Direct Growth on Fluorine-Doped Tin Oxide (FTO)/rGO Substrate ». Journal of Computational and Theoretical Nanoscience 17, no 2 (1 février 2020) : 886–92. http://dx.doi.org/10.1166/jctn.2020.8736.
Texte intégralRésumé :
Titanium dioxide or titania shows a great interest in solar cell application due to its morphology and crystalline structure. Moreover, it is an affordable compound that could make solar cells more cost economical than traditional silicon solar cells. In this study, the influence of rutile Titanium Dioxide (TiO2) deposit on reduced Graphene Oxide (rGO) as photoanode through one-step hydrothermal technique is demonstrated to synthesis rutile TiO2 nanorods (NRs) and nanoflowers (NFs) morphology in nanoscale dimension with different rGO volume for Dye-sensitized solar cells (DSSCs) application. The successful synthesis of TiO2 on FTO/rGO was confirmed using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy, ultraviolet-visible (UV-Vis) spectrophotometry and incident photon-to-current conversion efficiency (IPCE) spectra. The performance of dye-sensitized solar cells as outcome of rGO contents in solar cell was also examined. The optimal performance result in contrast with liquid electrolyte based solar cell has been approved over photovoltaic performance study in terms characteristics of open circuit voltage (Voc), short circuit current (Jsc) and solar conversion efficiency.
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Faznny, M. F., Mohamed Kamari Halimah, Amirah Abdul Latif, Farah Diana Muhammad et Laoding Hasnimulyati. « Optical Properties of La3+ NPs/Ag+ Co-Doped Zinc Borotellurite Glass ». Solid State Phenomena 290 (avril 2019) : 3–8. http://dx.doi.org/10.4028/www.scientific.net/ssp.290.3.
Texte intégralRésumé :
Lanthanum and silver co-doped zinc borotellurite glasses having chemical composition of [{[(TeO2)0.7(B2O3)0.3]0.7(ZnO)0.3}0.96 (La NPs)0.04]1-x(Ag2O)x with 0.02 ≤ x ≤ 0.10 molar fraction were fabricated via melt-quenching technique. X-ray diffraction (XRD) analysis confirmed the amorphous nature of the samples through the presence of broad hump instead of sharp peaks. Optical properties of the samples were determined through ultraviolet-visible spectroscopy (UV-Vis) in the range of 220 to 800 nm. Fundamental absorption edge observed in the optical absorption spectra shifts to longer wavelength as the concentration of silver in the glass system increases. Decreasing trend for indirect energy band gap and increasing trend of Urbach energy values with the increment of Ag content suggest the contribution of Ag to the formation of nonbridging oxygen. Enhanced optical properties of the prepared glass hints the possible application of the glass material as optical fiber in photonic field.
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Ghoshal, Sib Krishna, Nurul Syuhada Mohamad Zake, Ramli Arifin, Md Rahim Sahar, Md Supar Rohani et Khaidzir Hamzah. « Optical Properties of Oxy-Chloride Tellurite Glass : Role of Samarium Ions ». Advanced Materials Research 1107 (juin 2015) : 437–42. http://dx.doi.org/10.4028/www.scientific.net/amr.1107.437.
Texte intégralRésumé :
. Achieving tunable optical properties of inorganic glasses via optimized doping of rare earth ions is ever-demanding in photonics. Control and inhibition of luminescence quenching, nonradiative decay and multi-phonon relaxation responsible of reduction of optical performance remains challenging. Doping/co-doping of different rare earth ions, variation of modifiers and embedding metallic nanoparticles (NPs) are thought as alternative routes to enhance optical response are still underway. We examine the influence of samarium ion concentrations on the optical properties of oxy-chlorite tellurite glasses of the form (70-x)TeO2-15MgO-5Li2O-10LiCl-xSm2O3 with 0.0 x 2.5 mol% prepared using melt-quenching method. The structural and optical characterizations are performed via X-ray diffraction (XRD), Ultraviolet-Visible (UV-Vis) absorption and photoluminescence (PL) spectroscopy. The glass density increased from 4.509 - 4.770 with the increase of Sm2O3 contents from 0.0 2.5 mol %. The XRD spectra confirm the amorphous nature of the glass. The absorption spectra exhibit nine prominent peaks corresponding to the transitions from the ground to excited states and the PL spectra reveal four peaks. The optical energy band gap for direct and indirect transitions are increased and Urbach energy decreased from 3.448 - 3.497, 3.165 - 3.232 and 0.217 - 0.175, respectively with the increase of Sm3+ ion concentrations. Furthermore, the significant enhancement in UV-Vis and PL response display the strong influence of samarium ion on optical and structural properties. The mechanism responsible for enhanced optical properties are analyzed and discussed. The results suggest that our careful experimental studies may contribute towards the development of tellurite glass based solid state lasers.
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Salayová, Aneta, Zdenka Bedlovičová, Nina Daneu, Matej Baláž, Zdenka Lukáčová Bujňáková, Ľudmila Balážová et Ľudmila Tkáčiková. « Green Synthesis of Silver Nanoparticles with Antibacterial Activity Using Various Medicinal Plant Extracts : Morphology and Antibacterial Efficacy ». Nanomaterials 11, no 4 (14 avril 2021) : 1005. http://dx.doi.org/10.3390/nano11041005.
Texte intégralRésumé :
A green synthetic route for the production of silver nanoparticles (AgNPs) using five different aqueous plant extracts, namely, Berberis vulgaris, Brassica nigra, Capsella bursa-pastoris, Lavandula angustifolia and Origanum vulgare, was investigated in this study. The present work demonstrates the influence of plant extract composition (antioxidant and total phenolic content) on the size and morphology of the produced AgNPs. The biosynthetic procedure was rapid and simple and was easily monitored via colour changes and ultraviolet and visible (UV-Vis) spectroscopy. Subsequently, measurement of zeta potential (ZP), photon cross-correlation spectroscopy (PCCS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and selected area electron diffraction (SAED) analysis were employed to characterise the as-synthesised nanoparticles. The XRD investigation confirmed the presence of Ag0 in the nanoparticles, and interactions between the bioactive compounds of the plants and the produced AgNPs were evident in the FTIR spectra. TEM indicated that the nanoparticles exhibited a bimodal size distribution, with the smaller particles being spherical and the larger having a truncated octahedron shape. In addition, the antimicrobial activity of the AgNPs was tested against five bacterial strains. All synthesised nanoparticles exhibited enhanced antimicrobial activity at a precursor concentration of 5 mM compared to the control substance, gentamicin sulphate, with the best results observed for AgNPs prepared with B. nigra and L. angustifolia extracts.
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KANOUNI, F., S. AMARA, A. ASSALI, F. ARAB et Q. ZOU. « TiO2/ZnO PHOTONIC CRYSTAL PREPARED BY SPRAY PYROLYSIS METHOD : APPLICATION TO MULTICHANNEL FILTER ». Surface Review and Letters 27, no 07 (29 novembre 2019) : 1950181. http://dx.doi.org/10.1142/s0218625x19501816.
Texte intégralRésumé :
Single-layer titanium dioxide (TiO2, ZnO, double-layer TiO2/ZnO and multilayer TiO2/ZnO/TiO2/ZnO were grown on ordinary glass substrate by ultrasonic spray deposition at 300∘C. Titanium chloride, zinc acetate and deionized water were employed as precursors. The ultraviolet–visible spectrometer spectra show that the quality of optical transmittance in visible wavelength range decreases as the number of bilayers increases. The crystalline phase of the thin films was identified through X-ray diffraction method with diffraction patterns scan used at 2[Formula: see text] from 10∘ to 90∘. From the DRX results, it is found that the crystallinity is enhanced when the number of TiO2/ZnO layers increased. From the 2D/3D atomic force microscopy (AFM) analysis, it is found that the surface of the films was covered by triangle-like particles. However, bilayer and multilayer TiO2/ZnO thin films show smooth and compacted surface roughnesses compared to single-layer TiO2 and ZnO, respectively. In addition to this experimental work, a multichannel filter based on TiO2/ZnO subphotonic crystals is suggested. The transmission properties of this filter have been investigated by means of the transfer-matrix method (TMM). The idea is to import a wedge of air with an apex angle as the defect layer to disturb the original periodicity of the oxide photonic crystal and generate some new kind of multichannel filtering properties.
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Hussein, Ahang M., Elham M. A. Dannoun, Shujahadeen B. Aziz, Mohamad A. Brza, Rebar T. Abdulwahid, Sarkawt A. Hussen, Sarkawt Rostam, Dalia M. T. Mustafa et Dana S. Muhammad. « Steps Toward the Band Gap Identification in Polystyrene Based Solid Polymer Nanocomposites Integrated with Tin Titanate Nanoparticles ». Polymers 12, no 10 (10 octobre 2020) : 2320. http://dx.doi.org/10.3390/polym12102320.
Texte intégralRésumé :
In the current study, the film fabrication of polystyrene (PS) based polymer nanocomposites (NCs) with tuned refractive index and absorption edge was carried out using the solution cast method. X-ray diffraction (XRD) and ultraviolet-visible (UV-Vis) light characterization techniques were performed. The structural and optical properties of the prepared films were specified. The hump of PS decreased significantly when SnTiO3 nanoparticles (NPs) were introduced. Sharp and high intense peaks of SnTiO3 NPs at a high filler ratio were observed. The crystalline size was determined for SnTiO3 NPs from the sharp crystalline peaks using Debye-Scherrer’s equation and was found to be 25.179 nm, which is close enough to that described by the supplier. Several optical parameters, such as absorption coefficient (α), refractive index (n), and optical dielectric properties, were investigated. The absorption spectra were tuned with increasing SnTiO3NPs. Upon the addition of the NPs to the PS host polymer, the absorption edge undergoes shifting to lesser photon energy sides. The optical dielectric constant (ε′) was correlated to the refractive index. The study of the optical band gap was conducted in detail using both Tauc’s model and the optical dielectric loss (ε″) parameter. The results showed that the ε″ parameter is noteworthy to be measured in the optical band gap study of materials.
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Jark, Werner. « A high-efficiency and high-spectral-resolution EUV/soft X-ray monochromator based on off-plane diffraction ». Journal of Synchrotron Radiation 27, no 1 (1 janvier 2020) : 25–30. http://dx.doi.org/10.1107/s1600577519014462.
Texte intégralRésumé :
The most efficient diffraction at a periodic grating structure is expected to take place when the incident radiation can be considered to have been specularly reflected off the inclined part of grooves that are positioned parallel to the trajectory of the incident beam. Very encouraging results for this configuration, in which the diffraction takes place off-plane, have been reported recently for a grating to be used in a spectrometer for space science investigations. This grating provided high efficiency for a relatively large groove density and a large blaze angle. High efficiency was observed even in higher diffraction orders up to the fourth order. Here the performance parameters, especially for the combination of diffraction efficiency and achievable spectral resolution, will be discussed for a grating used in a grazing-incidence plane-grating monochromator for monochromatization of synchrotron radiation in the extreme ultraviolet (EUV) and soft X-ray range with photon energies between 30 eV and 2000 eV. It is found that the instrument can provide competitive spectral resolution in comparison with the use of in-plane diffraction. In the case of comparable spectral resolution, the off-plane diffraction is found to provide superior efficiency.
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Jark, Werner. « On the advantages of operation in second-order diffraction of blazed gratings in soft X-ray monochromators ». Journal of Synchrotron Radiation 26, no 5 (23 août 2019) : 1587–91. http://dx.doi.org/10.1107/s1600577519009421.
Texte intégralRésumé :
The fact that a diffraction grating can provide twofold-smaller bandwidth when operated in second-order diffraction is long known and applied routinely in the laboratory for spectroscopy in the visible and ultraviolet spectral range. A similar routine operation in monochromators for the soft X-ray range is not reported yet. This study will thus address the feasibility of efficient diffraction of soft X-rays in the second order at reflection gratings when operated at grazing angles of incidence. The related systematic study could make profitable use of a recently introduced simple analytical equation for the prediction of the diffraction efficiency of blazed gratings with an ideal sawtooth profile. The predictions are then verified by use of rigorous calculations. The principle finding is that, by operation of gratings with lower groove densities, and thus with higher efficiencies, in higher order diffraction, one can extend the tuning in existing instruments with mechanical/optical limitations to larger photon energies. The performance in terms of transmission and spectral resolving power can be very similar to the performance of a grating with a larger groove density, which would otherwise have to be used for accessing the same energy range. This would allow operation of a single highly efficient grating over a larger photon energy interval at a modern synchrotron radiation source, e.g. from 0.3 to 2.2 keV. Without any requirement for a sophisticated grating exchange scheme, a related instrument promises to be sufficiently stable for the needs imposed by the improvements in source point stability at diffraction-limited storage rings.
Thèses sur le sujet "Ultraviolet spectra, Photons, X-ray diffraction"
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Zhang, Zhipeng, Wenckstern Holger von, Jörg Lenzner et Marius Grundmann. « Wavelength-selective ultraviolet (Mg,Zn)O photodiodes : Tuning of parallel composition gradients with oxygen pressure ». American Institute of Physics, 2016. https://ul.qucosa.de/id/qucosa%3A23555.
Texte intégralRésumé :
We report on ultraviolet photodiodes with integrated optical filter based on the wurtzite (Mg,Zn)O
thin films. Tuning of the bandgap of filter and active layers was realized by employing a
continuous composition spread approach relying on the ablation of a single segmented target in
pulsed-laser deposition. Filter and active layers of the device were deposited on opposite sides of a
sapphire substrate with nearly parallel compositional gradients. Ensure that for each sample position
the bandgap of the filter layer blocking the high energy radiation is higher than that of the
active layer. Different oxygen pressures during the two depositions runs. The absorption edge is
tuned over 360 meV and the spectral bandwidth of photodiodes is typically 100 meV and as low as
50 meV.
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ROMANO, REBECA da S. G. « Estudo da irradiação do polipropileno para possibilitar o controle de sua degradação ambiental ». reponame:Repositório Institucional do IPEN, 2017. http://repositorio.ipen.br:8080/xmlui/handle/123456789/28012.
Texte intégralRésumé :
Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2017-11-16T17:00:32Z
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O PP é descartado em grande quantidade no meio ambiente, tendo em vista seu consumo muito elevado derivado de suas excelentes propriedades químicas e físicas, boa processabilidade e baixo custo. As radiações ionizantes, não ionizantes (UV e infravermelho), bem como o oxigênio e os poluentes podem causar a degradação do polipropileno (PP). A exposição à radiação ionizante pode causar na molécula de PP cisão de cadeia principal, reticulação e peroxidação (na presença de ar) entre outras. Este estudo tem como objetivo, o desenvolvimento de um PP oxidegradável por meio do controle da degradação induzida por radiação ionizante. As amostras foram processadas por injeção e expostas ao envelhecimento natural durante 180 dias e ao envelhecimento acelerado em estufa á 100°C por 192 dias e depois caracterizadas por avaliação visual, ensaios mecânicos, FTIR, SEM, DSC, TGA e DRX. As amostras de PP Grão 20 kGy, após o envelhecimento natural, apresentaram maior oxidação com presença de fissuras superficiais mais intensamente do que o PP d2w®. A resistência a tração do PP irradiado foi superior ao PP d2w® e os resultados do alongamento na ruptura mostraram uma diminuição intensa se compararmos o PP irradiado e o PP d2w® com o PP. Após a exposição natural espécies os índices de vinila e carbonila aumentaram ligeiramente devido as reações Norrish. O grupo carbonila promove uma oxidação contínua, junto à superfície fazendo com que o polímero diminua sua massa molar. O efeito da degradação natural foi evidente na ordem PP Grão 20 kGy > PP Grão 12,5 kGy = PP d2w® > PP. Por conseguinte, este conceito pode ser utilizado para produzir um PP com propriedades oxi-degradáveis de uma forma controlável.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
Chapitres de livres sur le sujet "Ultraviolet spectra, Photons, X-ray diffraction"
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« Green and One-Pot Synthesis of Mint Derived Carbon Quantum Dots for Metal Ion Sensing ». Dans Materials Research Foundations, 81–94. Materials Research Forum LLC, 2021. http://dx.doi.org/10.21741/9781644901250-3.
Texte intégralRésumé :
A green and simple synthesis of carbon quantum dots (CQDs) was derived from dried mint leaves by hydrothermal method. Crystalline structure of the synthesized CQDs was characterized with X-ray diffraction (XRD) method. The morphological properties of the CQDs were investigated with transmission electron microscopy (TEM). The optical behaviors of the CQDs were examined with fourier transfom infrared spectrophotometer (FT-IR), ultraviolet visible (UV-Vis) and photoluminescence spectrophotometer techniques. Crystalline structure of the CQDs was found as amorphous in nature and the average diameter of the CDs was calculated as 8.13 nm from TEM study. According to the fluorescence emission spectra of the samples, synthesized CQDs was sensitive to mainly Ag(I), Cr(III) and Fe(III) ions. Especially, Ag(I) was the most sensible compared to other metal ions. Quenching effect of the CQDs was also evaluated by using ascorbic acid to metal ions added CQDs samples. Ascorbic acid showed the quenching effect for all the metal ion added samples except Sn(II) ion.
Actes de conférences sur le sujet "Ultraviolet spectra, Photons, X-ray diffraction"
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Roy, Manosi, et Dhananjay Kumar. « Blue Shift in Ultraviolet Absorption Spectra of Oxygen Doped Titanium Nitride Thin Films ». Dans ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-24113.
Texte intégralRésumé :
Abstract The objective of this study is to investigate the effect of film thickness on the bandgap of oxygen (O2)-doped titanium nitride (TiN) thin films. To accomplish this, high-quality two-dimensional O2-doped TiN films have been prepared on single-crystal sapphire substrates using a pulsed laser deposition method. The film thicknesses were varied from 3 to 100 nm by varying the number of laser pulses, while other deposition parameters are kept constant. X-ray diffraction (XRD) patterns have shown that the films grow in (111) orientation on the sapphire substrate. The increase in the intensity of the XRD (111) peak also demonstrates a better orientational alignment of the TiN films with substrate as the film thickness increases. The x-ray rocking curve has been used to measure the full width half maxima (FWHM) for each film. The FWHM values has been found to vary from 0.07 to 0.2° as the film thickness decreases. This is taken to indicate that the grain size decreases with a decrease in film thickness. Ultraviolet visible spectroscopy measurements in the wavelength range (200–800 nm) have been performed as well, which indicates an increase in the bandgap of O2-doped TiN films with a decrease in film thickness. The decrease in the film thickness leads to a blue shift of the peak in the ultraviolet-visible absorption (UV-A) region; this blueshift is accompanied by an increase in the bandgap of O2-doped TiN from 3.2 to 3.8 eV. The change in the bandgap due to a change in film thickness has been explained using the quantum confinement effect.
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Kalniņa, Aija. « Ar divvērtīgā mangāna joniem aktivēta magnija germanāta materiāla ilgspīdošā luminiscence ». Dans LU Studentu zinātniskā konference "Mundus et". LU Akadēmiskais apgāds, 2021. http://dx.doi.org/10.22364/lu.szk.2.rk.09.
Texte intégralRésumé :
In the course of study, 10 different MgGeO3:Mn2+ samples with different manganese 2+ ion concentrations were synthesized: 0 mol%, 0.1 mol%, 0.25 mol%, 0.5 mol%, 0.75 mol%, 1 mol%, 1.5 mol%, 2 mol%, 5 mol% and 10 mol%. The samples emit a good luminescence in the red spectrum diapason and can be excited by ultraviolet radiation and X-rays. Samples can shine for up to more than 10 hours after excitation. X-ray diffraction, excitation spectra, luminescence spectra, afterglow spectra, extinction kinetics and thermostimulated luminescence were measured for samples. The obtained results provide the basis for assessing the processes taking place in the materials and the effect that the concentration of admixture ions has on the luminescence. Perhaps in the future it will be possible to use magnesium germanate in medical diagnostic equipment, yielding a further improved insight into the human body. In this case, the results of the study will be useful for medical application.
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Bhagyaraj, Sneha, et Igor Krupa. « Alginate-Mediated Synthesis of Hetero-Shaped Silver Nanoparticles and their Hydrogen Peroxide Sensing ability ». Dans Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0042.
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Silver nanoparticles have been the focus of extensive research for many decades due to their unique physical, chemical and electrical properties. Introducing new environmentally benign methods for the synthesis of silver nanoparticles is of great interest in the research community. In this work we propose a new method for the simple synthesis of stable heterostructured biopolymer (sodium alginate)-capped silver nanoparticles (Ag-NPs) based on green chemistry.The as-prepared nanoparticles were characterized using the ultraviolet–visible (UV–Vis) absorption spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and Dynamic light scattering (DLS) techniques. The results showed that the as-prepared Ag-NPs have a heterostructured morphology with particle size in the range 30 ± 18 – 60 ± 25 nm, showing a zeta potential of -62 mV. The silver nanoparticle formation was confirmed from UV-Vis spectra showing 424 nm as maximum absorption. The particle size and crystallinity of the as- synthesized nanoparticles were analyzed using TEM and XRD measurements respectively. FTIR spectra confirmed the presence of alginate as capping agent to stabilize the nanoparticles. The Ag-NPs also showed excellent sensing capability, with a linear response to hydrogen peroxide spanning a wide range of concentrations from 10-1 – 10-7 M, which indicates their high potential for water treatment applications, such as pollution detection and nanofiltration composites.