scholarly journals Attenuation parameters of polyvinyl alcohol-tungsten oxide composites at the photon energies 5.895, 6.490, 59.54 and 662 keV

2020 ◽  
Vol 26 (2) ◽  
pp. 77-85
Author(s):  
M V Muthamma ◽  
Bubbly S Gudennavar ◽  
Shivappa B Gudennavar
Keyword(s):  
Polyvinyl Alcohol ◽  
Direct Method ◽  
Composite Films ◽  
Effective Atomic Number ◽  
X Ray Diffraction ◽  
X Ray ◽  
Noticeable Increase ◽  
Conductivity Property ◽  
Solution Cast ◽  
Γ Ray

AbstractThe growing demand for lightweight, non-toxic and effective X- and γ-ray shielding materials in various fields has led to the exploration of various polymer composites for shielding applications. In this study, tungsten filled polyvinyl alcohol (PVA) composites of varying WO3 concentrations (0 - 50 wt%) were prepared by solution cast technique. The structural, morphological, and thermal properties of the prepared composite films were studied using X-ray diffraction technique (XRD), Scanning electron microscopy (SEM) and Thermogravimetric analysis (TGA). The AC conductivity studies showed the low conductivity property of the composites. The X-ray (5.895 and 6.490 keV) and γ-ray (59.54 and 662 keV) attenuation studies performed using CdTe and NaI(Tl) detector spectrometers revealed a noticeable increase in shielding efficiency with increase in filler wt%. The effective atomic number (Zeff) calculated by the direct method agreed with the values obtained using Auto-Zeff software. The % heaviness showed that tungsten filled polyvinyl alcohol composites are lighter than traditional shielding materials.

Induced Alignment of a Solution-Cast Discotic Hexabenzocoronene Derivative for Electronic Devices Investigated by Surface X-ray Diffraction

2003 ◽  
Vol 125 (8) ◽  
pp. 2252-2258 ◽  
Author(s):  
Oliver Bunk ◽  
Martin M. Nielsen ◽  
Theis I. Sølling ◽  
Anick M. van de Craats ◽  
Natalie Stutzmann
Keyword(s):  
Electronic Devices ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solution Cast

scholarly journals The Effect of Polyvinyl Alcohol Concentration on the Growth Kinetics of KTiOPO4 Nanoparticles Synthesized by the Co-precipitation Method

2020 ◽  
Vol 1 (4) ◽  
pp. 187-193
Author(s):  
Elaheh Gharibshahian
Keyword(s):  
Polyvinyl Alcohol ◽  
Shape Control ◽  
Second Harmonic ◽  
Precipitation Method ◽  
Capping Agent ◽  
X Ray Diffraction ◽  
X Ray ◽  
Size And Shape ◽  
Diffraction Patterns ◽  
Co Precipitation

KTiOPO4 nanoparticles are known as the best candidate to utilize for second-harmonic generation in multiphoton microscopes and bio labels. Size and shape are important and effective parameters to control the properties of nanoparticles. In this paper, we will investigate the role of capping agent concentration on the size and shape control of KTP nanoparticles. We synthesized KTP nanoparticles by the co-precipitation method. Polyvinyl alcohol with different mole ratios to titanium ion (1:3, 1:2, 1:1) was used as a capping agent. Products were examined by X-ray diffraction patterns and scanning electron microscopy analyses. X-ray diffraction patterns confirmed the formation of the KTP structure. The biggest (56.36nm) and smallest (39.42nm) grain size were obtained by 1:3 and 1:1 mole ratios of capping agent, respectively. Dumbly, spherical and polyhedral forms of KTP nanoparticles were observed by the change in capping agent mole ratio. The narrowest size distribution of KTiOPO4 nanoparticles was obtained at 1:1 mole ratio of capping agent. Doi: 10.28991/HIJ-2020-01-04-06 Full Text: PDF

scholarly journals Preparation and Assessment of Heat-Treated α-Chitin Nanowhiskers Reinforced Poly(viny alcohol) Film for Packaging Application

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1883 ◽  
Author(s):  
Chao Peng ◽  
Guangxue Chen
Keyword(s):  
Heat Treatment ◽  
Composite Films ◽  
Barrier Properties ◽  
Mechanical Tests ◽  
Light Transmittance ◽  
Poly Vinyl Alcohol ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Chitin Nanowhiskers

In this study, poly(vinyl alcohol) (PVA) composite films enhanced by α-chitin nanowhiskers (ChWs) were prepared through heat treatment. The obtained membranes were assessed by means of FTIR spectroscopy, X-ray diffraction, thermogravimetric analysis, regular light transmittance, mechanical tests, permeability and water absorption. The influence of the nano-component and heat treatment on the mechanical, thermal and water-resistant properties of the composite membrane were analyzed. From the results of the work, the produced films with excellent barrier properties and inexpensive raw processed materials have great prospects in packaging applications.

scholarly journals Preparation and characterization of polyani-line/polyvinyl alcohol nanocomposite by laser irradiation

2017 ◽  
Vol 6 (4) ◽  
pp. 77
Author(s):  
N A M Shahin ◽  
S Abd El Mongy ◽  
R Kamal ◽  
A B El- Bially ◽  
A A Shabaka ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Relaxation Time ◽  
Polyvinyl Alcohol ◽  
Laser Irradiation ◽  
Imaginary Part ◽  
Electronic Transition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Amorphous Nature

Polyaniline (PANI) - Polyvinyl alcohol (PVA) nanocomposite were prepared using laser irradiation method. X-ray diffraction results showed that, (PANI/PVA) nanocomposite exhibited amorphous nature of polymer. The electronic transition will be studied using Ultraviolet-Visible spectrometer (UV-Vis). The real part of dielectric constant (έ) and imaginary part (ε") were studied. Also, the relaxation time was calculated.

Interfacial Characterization of Mosi2+ X Sic Composite Thin Films on Molybdenum Substrates

1996 ◽  
Vol 458 ◽  
Author(s):  
S. Govindarajan ◽  
J. J. Moore ◽  
T. R. Ohno ◽  
J. Disam
Keyword(s):  
Composite Film ◽  
Composite Films ◽  
Carbon Diffusion ◽  
Detailed Examination ◽  
X Ray Diffraction ◽  
Diffusion Anneal ◽  
Temperature Oxidation ◽  
X Ray ◽  
Diffusion Barrier Layer

ABSTRACTA novel coating architecture is being examined for enhancing the high temperature, oxidation resistance of molybdenum. The coating incorporates a thin, composite film of MoSi2+1.96 mole fraction SiC in order to match the coefficients of thermal expansion between the molybdenum substrate and the coating. Since the as-deposited composite film is amorphous in nature, a diffusion anneal treatment is carried out at 1000°C to achieve crystallization of the film. In this paper, a detailed examination of the Mo-MoSi2+1.96 SiC interface will be presented. The microstructural features of the composite films will be discussed based on electron microscopy, auger electron spectroscopy (AES), and X-ray diffraction analysis. Finally, a novel diffusion barrier layer for minimizing silicon and carbon diffusion from the coating to the substrate will be discussed.

Study of the structure and thermal characteristics of nanocomposites based on polyvinyl alcohol and intercalated montmorillonite

2019 ◽  
pp. 089270571987919
Author(s):  
Volodymyr Krasinskyi ◽  
Ivan Gajdos ◽  
Oleh Suberlyak ◽  
Viktoria Antoniuk ◽  
Tomasz Jachowicz
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Acrylic Acid ◽  
Polyvinyl Alcohol ◽  
Thermal Characteristics ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
The Degree Of Crystallinity

The structure and thermal characteristics of nanocomposites based on polyvinyl alcohol (PVA) and montmorillonite (MMT) intercalated with polyvinylpyrrolidone were investigated by X-ray diffraction analysis and differential scanning calorimetry. The modification of PVA with intercalated MMT reduces the degree of crystallinity of the resulting nanocomposites but significantly increases their thermal stability. Under ultrasound, the intercalated MMT was completely distributed in a PVA solution and formed a monocrystalline structure. Films based on PVA with modified MMT were cross-linked at 110°C in the presence of 5 wt% acrylic acid and 0.5 wt% Ferrous(II) sulfate as an initiator. The formed films have a homogeneous cross-linked structure.

scholarly journals Effect of the Organobentonite Filler on Structure and Properties of Composites Based on Hydroxyethyl Cellulose

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Olga V. Alekseeva ◽  
Anna N. Rodionova ◽  
Nadezhda A. Bagrovskaya ◽  
Alexander V. Agafonov ◽  
Andrew V. Noskov
Keyword(s):  
Tensile Properties ◽  
Composite Films ◽  
Nitrogen Adsorption ◽  
Hydroxyethyl Cellulose ◽  
X Ray Diffraction ◽  
Ir Spectrometry ◽  
X Ray ◽  
Mechanical Dispersion ◽  
Filling Agent ◽  
Adsorption Desorption

Organobentonite powder was synthesized and characterized using laser diffraction, X-ray diffraction, low-temperature nitrogen adsorption-desorption technique, and dynamic light scattering. Obtained powder was found as material with mesopores. The organobentonite particles were larger than pure bentonite one. Hydroxyethyl cellulose (HEC) was filled with organobentonite particles by mechanical dispersion, and produced composite films were researched by the number of methods. New data relating to structure, tensile properties, and antimicrobial activity of HEC/organobentonite composites were obtained. Using results of X-ray diffraction, the reflections assigned to crystal filler in polymer material were proved. Concentration effect of the filling agent on tensile properties of composite film was revealed. Data of infrared (IR) spectrometry indicated a decrease in the density of hydrogen-bond net in HEC/organobentonite composite as compared with pristine HEC. Using microbiological tests, it was found that the HEC/organobentonite films exhibited bacteriostatic action against S. aureus and fungistatic action against molds.

Preparation and photoelectrochemical performance of nano Bi2S3–TiO2 composites

2018 ◽  
Vol 11 (03) ◽  
pp. 1850055 ◽  
Author(s):  
Senlin Li ◽  
Jinliang Huang ◽  
Xiangmei Ning ◽  
Yongchao Chen ◽  
Qingkui Shi
Keyword(s):  
Solvothermal Method ◽  
Composite Films ◽  
Great Influence ◽  
Photocurrent Density ◽  
Tetrabutyl Titanate ◽  
X Ray Diffraction ◽  
Photoelectrochemical Performance ◽  
X Ray ◽  
External Bias ◽  
Transmission Electron

TiO2 nanorod (NR) arrays were prepared on FTO by the simple hydrothermal synthesizing method. On this basis, a layer of Bi2S3 quantum dots (QDs) was covered on the surface of TiO2 NRs array by solvothermal method, by which the Nano Bi2S3/TiO2 NRs composites films were obtained. The phase structure, morphologies, optical absorptions and photoelectrochemical (PEC) properties of the as-prepared materials were characterized by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Ultraviolet–visible spectroscopy (UV-Vis), Photoluminescence (PL) and electrochemical workstation. The results indicate that the concentration of tetrabutyl titanate (TBT) has a great influence on the morphology of the film, with the increase of TBT content, the array of TiO2 NRs changed from loose to tight, and the thin films were cracked when the TBT volume is up to 0.7[Formula: see text]mL; The absorption of the TiO2 NRs array film to the visible light is enhanced significantly when sensitized with Bi2S3 and the absorption wavelength is increased from 400[Formula: see text]nm to 800[Formula: see text]nm. Compared with the pure TiO2, the fluorescence intensity of the TiO2/Bi2S3 NRs is weakened, and there is no obvious fluorescence diffraction peak. Under the irradiation of standard (AM1.5[Formula: see text]G 100[Formula: see text]mW/cm[Formula: see text], the photocurrent density of the composite film increased significantly. When the external bias voltage is 1.2[Formula: see text]V, the current density of the composite films is five times of that of the pure TiO2.

scholarly journals Preparation of N-Doped TiO2-ZrO2Composite Films under Electric Field and Heat Treatment and Assessment of Their Removal of Methylene Blue from Solution

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Lefu Mei ◽  
Ranfang Zuo ◽  
Jing Xie ◽  
Libing Liao ◽  
Hao Ding
Keyword(s):  
Methylene Blue ◽  
Electric Field ◽  
Visible Light ◽  
Composite Film ◽  
Photoelectron Spectroscopy ◽  
Composite Films ◽  
Partial Replacement ◽  
Cutoff Wavelength ◽  
X Ray Diffraction ◽  
X Ray

TiO2-ZrO2composite film with the grain size of 50 nm was synthesized by electric field and heat (EF&H) treatments. Portions of O atoms in the TiO2network structure were replaced by N atoms as revealed by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses, suggesting formation of a nonstoichiometric compoundTiO2-xNxon the composite film. The UV-Vis spectra of the film suggested that the visible light with wavelength of 550 nm could be absorbed for the N-doped composite film after EF&H treatment in comparison to a cutoff wavelength of 400 nm for the composite film without EF treatment. Photocatalytic experiments showed that the degradation rate of methylene blue by N-doped composite films increased significantly under visible light irradiation. The partial replacement of O by doped N played a very important role in narrowing the band gap and improving the visible light photocatalytic reactivity.

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