Comparison between the UV and X-ray Photosensitivities of Hybrid TiO2-SiO2 Thin Layers

The photo-induced effects on sol–gel-based organo TiO2-SiO2 thin layers deposited by the dip-coating technique have been investigated using two very different light sources: A light-emitting diode (LED) emitting in the UV (at 365 nm, 3.4 eV) and an X-ray tube producing 40 keV mean-energy photons. The impact of adding a photo-initiator (2,2-dimethoxy-2-phenylacetophenone-DMPA) on the sol–gel photosensitivity is characterized namely in terms of the photo-induced refractive index measured through M-line spectroscopy. Results show that both silica-titania sol–gel films with or without the photo-initiator are photosensitive to both photon sources. The induced refractive index values reveal several features where slightly higher refractive indexes are obtained for the sol–gel containing the photo-initiator. UV and X-ray-induced polymerization degrees are discussed using Fourier-transform infrared (FTIR) spectroscopy where the densification of hybrid TiO2-SiO2 layers is related to the consumption of the CH=C groups and to the decomposition of Si-OH and Si-O-CH3 bonds. X-rays are more efficient at densifying the TiO2-SiO2 inorganic and organic network with respect to the UV photons. Hard X-ray photolithography, where no cracks or damages are observed after intense exposition, can be a promising technique to design submicronic-structure patterns on TiO2-SiO2 thin layers for the building of optical sensors.

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Effect of Dip-Coating Cycle on Some Physical Properties of Cu2NiSnS4 Thin Films for Photovoltaic Applications

10.21203/rs.3.rs-194196/v1 ◽

2021 ◽

Author(s):

Ahmed ZITI ◽

Bouchaib HARTITI ◽

Amine BELAFHAILI ◽

Hicham LABRIM ◽

Salah FADILI ◽

...

Keyword(s):

Thin Films ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Sol Gel ◽

Dip Coating ◽

Visible Spectroscopy ◽

X Ray ◽

Uv Visible ◽

The Impact ◽

Scanning Electron

Abstract Quaternary semiconductor Cu2NiSnS4 thin film was made by the sol-gel method associated to dip-coating technique on ordinary glass substrates. In this paper, we have studied the impact of dip-coating cycle at different cycles: 4, 5 and 6 on the structural, compositional, morphological, optical and electrical characteristics. CNTS thin films have been analyzed by various characterization techniques including: X-ray diffractometer (XRD), Raman measurements, scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDS), UV-visible spectroscopy and four-point probe method. XRD spectra demonstrated the formation of cubic Cu2NiSnS4 with privileged orientation at (111) plane. Crystallite size of cubic CNTS thin films increase with from 6.30 to 9.52 with dip-coating cycle augmented. Raman scattering confirmed the existence of CNTS thin films by Raman vibrational mode positioned at 332 cm− 1. EDS investigations showed near-stoichiometry of CNTS sample deposited at 5 cycles. Scanning electron microscope showed uniform surface morphologies without any crack. UV-visible spectroscopy indicated that the optical absorption values are larger than 104 cm− 1, Estimated band gap energy of CNTS absorber layers decrease from 1.64 to 1.5 eV with dip-coating cycle increased. The electrical conductivity of CNTS thin films increase from 0.19 to 4.16 (Ω cm)-1. These characteristics are suitable for solar cells applications.

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Titania-Coated Alumina Foam Photocatalyst for Memantine Degradation Derived by Replica Method and Sol-Gel Reaction

Materials ◽

10.3390/ma13010227 ◽

2020 ◽

Vol 13 (1) ◽

pp. 227 ◽

Cited By ~ 2

Author(s):

Zrinka Švagelj ◽

Vilko Mandić ◽

Lidija Ćurković ◽

Martina Biošić ◽

Irena Žmak ◽

...

Keyword(s):

Tio2 Nanoparticles ◽

Tio2 Film ◽

High Performance ◽

Light Emitting Diode ◽

Sol Gel ◽

Dip Coating ◽

Replica Method ◽

X Ray Diffraction ◽

Characterization Methods ◽

X Ray

In the present work, alumina (Al2O3) foam was prepared by the replica method where a polyurethane (PU) foam (30 pores per inch (ppi)) template was impregnated with a 60 wt.% Al2O3 suspension. Sintered Al2O3 foam was used as substrate for the deposition of sol-gel derived titania (TiO2) film using dip coating. For the preparation of TiO2 sol, titanium(IV) isopropoxide (Ti-iPrOH) was used as the precursor. The common problem of qualification and quantification of a crystalline coating on a highly porous 3D substrate with an uneven surface was addressed using a combination of different structural characterization methods. Using Powder X-ray Diffraction (PXRD) and synchrotron Grazing Incidence X-ray Diffraction (GIXRD) on bulk and powdered Al2O3 foam and TiO2-coated Al2O3 foam samples, it was determined Al2O3 foam crystallizes to corundum and coating to anatase, which was also confirmed by Fourier Transformed Infrared Spectroscopy (FTIR). Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDS) revealed the structural and microstructural properties of the substrate and coating. Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) were used to clarify the evolution of the porous microstructure. The Al2O3-TiO2 composite was evaluated as a photocatalyst candidate for the degradation of the micropollutant medication memantine. The degradation rate was monitored using a light-emitting diode (LED) lamp operating at electromagnetic (EM) wavelength of 365 nm. The photocatalytic activity of sol-gel-derived TiO2 film immobilized on the Al2O3 foam was compared with commercially available TiO2 nanoparticles, P25-Degussa, in the form of a suspension. The levels of memantine were monitored by High-Performance Liquid Chromatography–Tandem Mass Spectrometry (HPLC–MS/MS). The efficiency and rate of the memantine photodegradation by suspended TiO2 nanoparticles is higher than the TiO2-coated Al2O3 foam. But, from the practical point of view, TiO2-coated Al2O3 foam is more appropriate as a valuable photocatalytic composite material.

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Optimization of Ormosil Glasses for Luminescence Based Dissolved Oxygen Sensors

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.161.1 ◽

2010 ◽

Vol 161 ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

J. Palmeira ◽

L. Lopes ◽

A.J. Silva ◽

P.A.S. Jorge ◽

A. Oliva

Keyword(s):

Dissolved Oxygen ◽

Optical Sensors ◽

Ruthenium Complex ◽

Oxygen Sensing ◽

Sol Gel ◽

Dip Coating ◽

Oxygen Sensors ◽

Quenching Efficiency ◽

Sol Gel Films ◽

The Impact

In the recent years, sol-gel films have been intensively used in optical sensors configurations. Due to its hydrophobic nature, ormosil films have been reported to be a promising supporting matrix for oxygen sensing dyes for measurements in aqueous media. In this work, the impact of the sol-gel host fabrication parameters in the characteristics of the resulting oxygen sensing membranes is thoroughly evaluated. Different combinations of organic-inorganic precursors, with different aging times, were tested as oxygen sensors. All the solution were doped with ruthenium complex Ru(II)-tris(4,7-diphenyl-1,10-phenanthroline) to introduce oxygen sensitivity. Thin films were produced by dip coating of glass slides. The oxygen sensitive films were tested in aqueous phase in equilibrium with different oxygen gas compositions, using a phase-modulation technique. Sensor performance parameters such as Stern-Volmer constant, quenching efficiency and lifetime response are reported. The data obtained clearly indicates that increased aging times and longer organic groups produce sensors with the highest sensitivity to dissolved oxygen. From all sol-gel films produced, the BTEOS:TEOS (1:1) mixture is the most promising for sensor construction.

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High-resolution electron microscopy study of a Si-Mo x-ray mirror

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126792 ◽

1987 ◽

Vol 45 ◽

pp. 400-401

Author(s):

R. Gronsky ◽

J. Punglia

Keyword(s):

Materials Science ◽

High Resolution Electron Microscopy ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Thin Layers ◽

Light Sources ◽

X Rays ◽

Optical Elements ◽

X Ray ◽

Resolution Electron

The science of x-ray optics has undergone rapid growth in recent years, spurned by the availability of high intensity light sources with tunable optical characteristics in the XUV spectral region which includes soft x-rays and ultraviolet radiation. The development of optical elements for use with XUV radiation has followed a parallel path of development with most recent emphasis being placed upon multilayer coatings that enhance the reflectivity of x-ray mirrors and at the same time provide spectral selectivity. In their simplest form, these coatings consist of alternating thin layers of two materials with different refractive indices that yield both the desired high reflectivity and a relatively broad wavelength bandpass. Additional considerations are based on their materials science: the multilayers must have atomically smooth interfaces and be resistant to interdiffusion or chemical reaction. A summary of their preparation and utilization is given in reference 3.

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X-ray Shielding, Mechanical, Physical, and Water Absorption Properties of Wood/PVC Composites Containing Bismuth Oxide

Polymers ◽

10.3390/polym13132212 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2212

Author(s):

Worawat Poltabtim ◽

Ekachai Wimolmala ◽

Teerasak Markpin ◽

Narongrit Sombatsompop ◽

Vichai Rosarpitak ◽

...

Keyword(s):

Impact Strength ◽

Water Absorption ◽

Attenuation Coefficient ◽

Bismuth Oxide ◽

Morphological Properties ◽

Linear Attenuation Coefficient ◽

X Rays ◽

Equivalent Thickness ◽

X Ray ◽

The Impact

The potential utilization of wood/polyvinyl chloride (WPVC) composites containing an X-ray protective filler, namely bismuth oxide (Bi2O3) particles, was investigated as novel, safe, and environmentally friendly X-ray shielding materials. The wood and Bi2O3 contents used in this work varied from 20 to 40 parts per hundred parts of PVC by weight (pph) and from 0 to 25, 50, 75, and 100 pph, respectively. The study considered X-ray shielding, mechanical, density, water absorption, and morphological properties. The results showed that the overall X-ray shielding parameters, namely the linear attenuation coefficient (µ), mass attenuation coefficient (µm), and lead equivalent thickness (Pbeq), of the WPVC composites increased with increasing Bi2O3 contents but slightly decreased at higher wood contents (40 pph). Furthermore, comparative Pbeq values between the wood/PVC composites and similar commercial X-ray shielding boards indicated that the recommended Bi2O3 contents for the 20 pph (40 ph) wood/PVC composites were 35, 85, and 40 pph (40, 100, and 45 pph) for the attenuation of 60, 100, and 150-kV X-rays, respectively. In addition, the increased Bi2O3 contents in the WPVC composites enhanced the Izod impact strength, hardness (Shore D), and density, but reduced water absorption. On the other hand, the increased wood contents increased the impact strength, hardness (Shore D), and water absorption but lowered the density of the composites. The overall results suggested that the developed WPVC composites had great potential to be used as effective X-ray shielding materials with Bi2O3 acting as a suitable X-ray protective filler.

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Impact of aging on gene expression response to x-ray irradiation using mouse blood

Scientific Reports ◽

10.1038/s41598-021-89682-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Constantinos G. Broustas ◽

Axel J. Duval ◽

Sally A. Amundson

Keyword(s):

Gene Expression ◽

Differentially Expressed Genes ◽

Differentially Expressed ◽

X Rays ◽

Gene Expression Response ◽

X Ray ◽

The Impact ◽

Old Mice ◽

Radiation Biodosimetry ◽

Young Mice

AbstractAs a radiation biodosimetry tool, gene expression profiling is being developed using mouse and human peripheral blood models. The impact of dose, dose-rate, and radiation quality has been studied with the goal of predicting radiological tissue injury. In this study, we determined the impact of aging on the gene expression profile of blood from mice exposed to radiation. Young (2 mo) and old (21 mo) male mice were irradiated with 4 Gy x-rays, total RNA was isolated from whole blood 24 h later, and subjected to whole genome microarray analysis. Pathway analysis of differentially expressed genes revealed young mice responded to x-ray exposure by significantly upregulating pathways involved in apoptosis and phagocytosis, a process that eliminates apoptotic cells and preserves tissue homeostasis. In contrast, the functional annotation of senescence was overrepresented among differentially expressed genes from irradiated old mice without enrichment of phagocytosis pathways. Pathways associated with hematologic malignancies were enriched in irradiated old mice compared with irradiated young mice. The fibroblast growth factor signaling pathway was underrepresented in older mice under basal conditions. Similarly, brain-related functions were underrepresented in unirradiated old mice. Thus, age-dependent gene expression differences should be considered when developing gene signatures for use in radiation biodosimetry.

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Characterization of ordered mesoporous films on silicon (001) surface using X-ray and electron diffraction

Journal of Applied Crystallography ◽

10.1107/s0021889804031498 ◽

2005 ◽

Vol 38 (1) ◽

pp. 211-216 ◽

Cited By ~ 5

Author(s):

Pang-Hung Liu ◽

Kuei-Jung Chao ◽

Xing-Jian Guo ◽

Kuo-Ying Huang ◽

Yen-Ru Lee ◽

...

Keyword(s):

Electron Diffraction ◽

Sol Gel ◽

Dip Coating ◽

Silica Film ◽

Continuous Film ◽

X Ray ◽

Transmission Electron ◽

Ordered Mesoporous ◽

Direction Dependence

A continuous silica film with well aligned mesochannels parallel to the Si(001) surface was found to be formed through sol–gel dip-coating of a silica precursor with nonionic ethylene oxide surfactant. Two two-dimensional mesoporous structures in centered and non-centered rectangular symmetries and with the short axes of elongated ellipsoidal pores normal to the surface were observed by X-ray and electron diffraction. Detailed transmission electron microscopy investigations were employed to view the direction dependence of the channel or pore packing in the continuous film.

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Ionic conductivity in nanocrystalline Gd doped ceria

MRS Proceedings ◽

10.1557/proc-1122-o06-02 ◽

2008 ◽

Vol 1122 ◽

Cited By ~ 1

Author(s):

Gianguido Baldinozzi ◽

David Simeone ◽

Dominique Gosset ◽

Mickael Dollé ◽

Georgette Petot-Ervas

Keyword(s):

Grain Size ◽

Ionic Conductivity ◽

Sol Gel ◽

Doped Ceria ◽

Narrow Size Distribution ◽

Conductivity Measurements ◽

X Ray Diffraction ◽

X Ray ◽

Grain Sizes ◽

The Impact

AbstractWe have synthesized Gd-doped ceria polycrystalline samples (5, 10, 15 %mol), having relative densities exceeding 95% and grain sizes between 30 and 160 nm after axial hot pressing (750 °C, 250 MPa). The samples were prepared by sintering nanopowders obtained by sol-gel chemistry methods having a very narrow size distribution centered at about 16 nm. SEM and X-ray diffraction were performed to characterize the sample microstructures and to assess their structures. We report ionic conductivity measurements using impedance spectroscopy. It is important to investigate the properties of these systems with sub-micrometric grains and as a function of their composition. Therefore, samples having micrometric and nanometric grain sizes (and different Gd content) were studied. Evidence of Gd segregation near the grain boundaries is given and the impact on the ionic conductivity, as a function of the grain size and Gd composition, is discussed and compared to microcrystalline samples.

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Impact of Slope of Growing Trays on Productivity of Wheat Green Fodder by a Nutrient Film Technique System

Water ◽

10.3390/w12113009 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3009

Author(s):

Andrius Grigas ◽

Aurelija Kemzūraitė ◽

Dainius Steponavičius ◽

Aušra Steponavičienė ◽

Rolandas Domeika

Keyword(s):

Light Emitting Diode ◽

Tap Water ◽

Slope Angle ◽

Experimental Studies ◽

Matter Content ◽

Light Sources ◽

Dry Matter Content ◽

Nutrient Film Technique ◽

Indoor Lighting ◽

The Impact

Application of hydroponic systems in feed production has not been extensively studied. Therefore, there is insufficient data on the effect of the slope of hydroponic growing trays used in the nutrient film technique on wheat fodder yield and its qualitative parameters. The slope of the trays has only been studied for food crops. This study conducted experimental research using a nutrient film technique hydroponic fodder growing device to evaluate the impact of growing tray slope angle on hydroponic wheat fodder production. The slope angle of the growing trays was changed from 2.0% (1.15°) to 8.0% (4.57°) with increments of 1.5% (0.86°). This research used two different light sources for wheat sprout illumination: indoor lighting (fluorescent lamps) and light-emitting diode illumination. In addition, two nutrient solutions were used for sprout irrigation: tap water and a solution enriched with macro- and microelements. Experimental studies confirmed the hypothesis that the slope angle of growing trays significantly affects the yield of wheat fodder grown for seven days. Analyzing the results, we found that the highest yield of wheat fodder after seven days of cultivation was achieved with growing trays sloped by 6.5% and using indoor lighting. In addition, we achieved the highest wheat fodder dry matter content using a 6.5% slope angle. Experimental studies also confirmed the hypothesis that using macro- and micronutrients in the nutrient solution does not significantly affect the yield of wheat fodder grown hydroponically for seven days.

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Mode Sensitivity Exploration of Silica–Titania Waveguide for Refractive Index Sensing Applications

Sensors ◽

10.3390/s21227452 ◽

2021 ◽

Vol 21 (22) ◽

pp. 7452

Author(s):

Muhammad A. Butt ◽

Andrzej Kaźmierczak ◽

Cuma Tyszkiewicz ◽

Paweł Karasiński ◽

Ryszard Piramidowicz

Keyword(s):

Refractive Index ◽

High Performance ◽

Near Infrared ◽

Sol Gel ◽

Cost Effective ◽

Dip Coating ◽

Infrared Wavelength ◽

Refractive Index Sensing ◽

Sensing Applications ◽

Coating Method

In this paper, a novel and cost-effective photonic platform based on silica–titania material is discussed. The silica–titania thin films were grown utilizing the sol–gel dip-coating method and characterized with the help of the prism-insertion technique. Afterwards, the mode sensitivity analysis of the silica–titania ridge waveguide is investigated via the finite element method. Silica–titania waveguide systems are highly attractive due to their ease of development, low fabrication cost, low propagation losses and operation in both visible and near-infrared wavelength ranges. Finally, a ring resonator (RR) sensor device was modelled for refractive index sensing applications, offering a sensitivity of 230 nm/RIU, a figure of merit (FOM) of 418.2 RIU−1, and Q-factor of 2247.5 at the improved geometric parameters. We believe that the abovementioned integrated photonics platform is highly suitable for high-performance and economically reasonable optical sensing devices.

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