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1.
Medicina (Kaunas) ; 59(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36984628

RESUMO

Background and Objectives: Quality assurance is an integral part of brachytherapy. Traditionally, radiographic films have been used for source position verification, however, in many clinics, computerized tomography simulators have replaced conventional simulators, and computerized radiography systems have replaced radiographic film processing units. With these advances, the problem of controlling source position verification without traditional radiographic films and conventional simulators has appeared. Materials and Methods: In this study, we investigated an alternative method for source position verification for brachytherapy applications. Source positions were evaluated using Gafchromic™ RTQA2 and EBT3 film and visually compared to exposed RTQA radiochromic film when using a Nucletron Oldelft Simulix HP conventional simulator and a Gammamed 12-i brachytherapy device for performance evaluation. Gafchromic film autoradiography was performed with a linear accelerator (LINAC) on-board imager (OBI). Radiochromic films are very suitable for evaluation by visual inspection with a LINAC OBI. Results: The results showed that this type of low-cost, easy-to-find material can be used for verification purposes under clinical conditions. Conclusions: It can be concluded that source-position quality assurance may be performed through a LINAC OBI device.


Assuntos
Braquiterapia , Dosimetria Fotográfica , Humanos , Dosagem Radioterapêutica , Dosimetria Fotográfica/métodos , Braquiterapia/métodos , Tomografia Computadorizada por Raios X
2.
Medicina (Kaunas) ; 59(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36837529

RESUMO

Background: During mammography, a lead-acrylic protective screen is recommended to reduce radiation exposure to the unexposed breast. Objectives: This research study aimed to construct an Indium-(III)-oxide-rich tellurite-glass screen (TZI8) and compare its performance to that of lead acrylic. Materials and Methods: A three-layer heterogeneous-breast phantom was developed, using the MCNPX (version 2.7.0) Monte Carlo code. An MCNPX-simulation geometry was designed and implemented, using the lead-acrylic and TZI8 shielding screens between the right and left breast. Next, the reliability of the phantom and the variations in absorption between the lead-acrylic and TZI8 glass were investigated. Results: The findings show that the TZI8-protective-glass screen offers significantly greater radioprotection than the lead-acrylic material. The quantity of total dose absorbed in the unexposed breast was much lower for TZI8 than for lead-based acrylic. The TZI8-glass screen gives about 60% more radioprotection than the lead-acrylic screen. Conclusion: Considering the toxic lead in the structure that may be hazardous to the human tissues, the TZI8-glass screen may be used in mammography examination to provide greater radioprotection than the lead-acrylic screen, in order to greatly reduce the dose to the unexposed breast.


Assuntos
Mama , Índio , Humanos , Reprodutibilidade dos Testes , Mamografia , Simulação por Computador
3.
Molecules ; 27(16)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36014341

RESUMO

Tannery industries are one of the extensive industrial activities which are the major source of chromium contamination in the environment. Chromium contamination has been an increasing threat to the environment and human health. Therefore, the removal of chromium ions is necessary to save human society. This study is oriented toward the preparation of a new triazole Schiff base derivatives for the remediation of chromium ions. 4,4'-((1E)-1,2-bis ((1H-1,2,4-triazol-3-yl) imino)ethane-1,2-diyl) diphenol was prepared by the interaction between 3-Amino-1H-1,2,4-triazole and 4,4'-Dihydroxybenzil. Then, the produced Schiff base underwent a phosphorylation reaction to produce the adsorbent (TIHP), which confirmed its structure via the different tools FTIR, TGA, 1HNMR, 13CNMR, GC-MS, and Phosphorus-31 nuclear magnetic resonance (31P-NMR). The newly synthesized adsorbent (TIHP) was used to remove chromium oxyanions (Cr(VI)) from an aqueous solution. The batch technique was used to test many controlling factors, including the pH of the working aqueous solution, the amount of adsorbent dose, the initial concentration of Cr(VI), the interaction time, and the temperature. The desorption behaviour of Cr(VI) changes when it is exposed to the suggested foreign ions. The maximum adsorption capacity for Cr(VI) adsorption on the new adsorbent was 307.07 mg/g at room temperature. Freundlich's isotherm model fits the adsorption isotherms perfectly. The kinetic results were well-constrained by the pseudo-second-order equation. The thermodynamic studies establish that the adsorption type was exothermic and naturally spontaneous.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Cromo/química , Humanos , Concentração de Íons de Hidrogênio , Íons , Cinética , Bases de Schiff , Triazóis , Águas Residuárias , Poluentes Químicos da Água/química , Purificação da Água/métodos
4.
Artigo em Inglês | MEDLINE | ID: mdl-26191984

RESUMO

In the present study 49 representative sites have been selected for the collection of water samples from central water supplies with different geographical locations in the region of Kavala, Northern Greece. Ten physicochemical parameters (pH, electric conductivity, nitrate, chloride, sodium, potassium, total alkalinity, total hardness, bicarbonate and calcium) were analyzed monthly, in the period from January 2010 to December 2010. Chemometric methods were used for monitoring data mining and interpretation (cluster analysis, principal components analysis and source apportioning by principal components regression). The clustering of the chemical indicators delivers two major clusters related to the water hardness and the mineral components (impacted by sea, bedrock and acidity factors). The sampling locations are separated into three major clusters corresponding to the spatial distribution of the sites - coastal, lowland and semi-mountainous. The principal components analysis reveals two latent factors responsible for the data structures, which are also an indication for the sources determining the groundwater quality of the region (conditionally named "mineral" factor and "water hardness" factor). By the apportionment approach it is shown what the contribution is of each of the identified sources to the formation of the total concentration of each one of the chemical parameters. The mean values of the studied physicochemical parameters were found to be within the limits given in the 98/83/EC Directive. The water samples are appropriate for human consumption. The results of this study provide an overview of the hydrogeological profile of water supply system for the studied area.


Assuntos
Cloretos/análise , Água Subterrânea/análise , Água Subterrânea/química , Nitratos/análise , Poluentes Químicos da Água/análise , Água/análise , Água/química , Monitoramento Ambiental/métodos , Grécia , Humanos , Análise de Componente Principal , Qualidade da Água , Abastecimento de Água
5.
Heliyon ; 10(4): e25932, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38370260

RESUMO

In this study, it was aimed to evaluate the effect of ethanol extract of Annona Muricata (AM) leaves in the prevention of brain damage caused by ionizing radiation (IR). This study was conducted in the Experimental Animal Research Unit of a university with 28 adults female Wistar Albino rats. The experimental groups were as follows: Control group (n = 8), AM group (n = 6), IR group (n = 8), AM + IR group (n = 6). In the IR group, astrocyte hypertrophy, microglial reaction and inflammatory reaction levels were significantly higher than the control and AM groups (P < 0.001). Edema was significantly higher in the IR group compared to the control group (P=0.001). The MDA of the IR group was significantly higher compared to the control group and AM group (P=0.031, P=0.006, respectively). The MDA of the AM + IR group was significantly higher than the AM group (P=0.039). Our findings show that histomorphology and oxidant damage caused by IR can be ameliorated using AM, as demonstrated by the comparison of the controls to AM + IR recipients, which showed similar histomorphology and oxidant damage levels.

6.
Sci Rep ; 14(1): 524, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177202

RESUMO

The treatment of tuberculosis is still a challenging process due to the widespread of pathogen strains resistant to antibacterial drugs, as well as the undesirable effects of anti-tuberculosis therapy. Hence, the development of safe and effective new anti-antitubercular agents, in addition to suitable nanocarrier systems, has become of utmost importance and necessity. Our research aims to develop liposomal vesicles that contain newly synthesized compounds with antimycobacterial action. The compound being studied is a derivative of imidazo-tetrazine named 3-(3,5-dimethylpyrazole-1-yl)-6-(isopropylthio) imidazo [1,2-b] [1,2,4,5] tetrazine compound. Several factors that affect liposomal characteristics were studied. The maximum encapsulation efficiency was 53.62 ± 0.09. The selected liposomal formulation T8* possessed a mean particle size of about 205.3 ± 3.94 nm with PDI 0.282, and zeta potential was + 36.37 ± 0.49 mv. The results of the in vitro release study indicated that the solubility of compound I was increased by its incorporation in liposomes. The free compound and liposomal preparation showed antimycobacterial activity against Mycobacterium tuberculosis H37Rv (ATCC 27294) at MIC value 0.94-1.88 µg/ml. We predict that the liposomes may be a good candidate for delivering new antitubercular drugs.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Lipossomos/farmacologia , Antituberculosos/farmacologia , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Testes de Sensibilidade Microbiana
7.
Heliyon ; 9(8): e18912, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37600407

RESUMO

WO3 effects on neutron and ionizing radiation defending factors of ternary tellurite-based glass blocks with molecular formula 80TeO2 -(20-x)WO3 - xK2O; x = 0-20 mol% (denoted as TKW-glass) has been reported via Phy-X theoretical calculations and Geant4 simulation code. Correlations between shielding factors and kinetics properties of the investigated glasses at different photon energy have been examined. The highest values of mass (MAC) attenuation coefficient were noted at 15 keV of the examined TKW-glass materials with the values of 38.408, 44.388, 49.855, 54.872, 59.492 cm2/g for TKW-0, TKW-5, TKW-10, TKW-15, and TKW-20, respectively. Generally, these values of the TKW-glasses obey the sequence: (TKW-0)MAC< (TKW-5)MAC < (TKW-10)MAC < (TKW-15)MAC < (TKW-20)MAC. The highest mean free path (MFP) values of TKW-glasses were registered at 15 MeV with the values of 6.101, 5.591, 5.097, 4.647, and 4.302 cm for TKW-0, TKW-5, TKW-10, TKW-15, and TKW-20, respectively. The two parameters half value layer (HVL) and MFP follow the pattern: (TKW-0)HVL, MFP > (TKW-5)HVL,MFP > (TKW-10)HVL,MFP > (TKW-15)HVL,MFP > (TKW-20)HVL,MFP. The maximum values of effective atomic number (EAN) took place at gamma energy of 15 keV corresponding to 44.35, 48.86, 52.63, 55.83, and 58.58 for TKW-0, TKW-5, TKW-10, TKW-15, and TKW-20, respectively. The trend of the buildup factors was similar for all of the glass specimens. The fast neutron removal cross-section (ΣR) enhanced as WO3 content increased in the specimens. Thus, the peaked value of ΣR is 0.1059 cm-1 was noted in the TKW-20 sample. Mechanical properties, neutron and γ-rays protection parameters were observed to improve with enhanced WO3 mol% in the TKW-glasses. The current results bear their utilization for neutron and gamma protection purposes.

8.
Heliyon ; 9(7): e17838, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37456003

RESUMO

We report the functional assessment of tungsten (VI) oxide on gamma-ray attenuation properties of 60Sb2O3-(40-x)NaPO3-xWO3 antimony glasses. The elemental mass-fractions and glass-densities of each glass sample are specified separately for the MCNPX Monte Carlo code. In addition to fundamental gamma absorption properties, Transmission Factors throughout a broad radioisotope energy range were measured. According to findings, holmium (Ho) incorporation into the glass structure resulted in a net increase of 0.3406 g/cm3, whereas cerium (Ce) addition resulted in a net increase of 0.2047 g/cm3. The 40% WO3 reinforced S7 sample was found to have the greatest LAC value, even though seven glass samples exhibited identical behavior. The S2 sample had the lowest HVL values among the glass groups evaluated in this work, computed in the energy range of 0.015-15 MeV. The lowest EBF and EABF values were reported for 40% WO3 reinforced S7 sample with the highest LAC and density values. According to the findings of this research, WO3 will likely make a significant contribution to the gamma ray absorption properties of antimony glasses, which are employed for optical and structural modification. Therefore, it can be concluded that WO3 may be treated monotonically and can be employed successfully in circumstances where gamma-ray absorption characteristics, optical properties, and structural qualities need to be enhanced.

9.
PLoS One ; 18(8): e0287422, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37535632

RESUMO

The utilization of phosphorite deposits as an industrial resource is of paramount importance, and its sustainability largely depends on ensuring safe and responsible practices. This study aims to evaluate the suitability of phosphorite deposits for industrial applications such as the production of phosphoric acid and phosphatic fertilizers. To achieve this goal, the study meticulously examines the geochemical characteristics of the deposits, investigates the distribution of natural Radioactivity within them, and assesses the potential radiological risk associated with their use. The phosphorites are massive and collected from different beds within the Duwi Formation at the Hamadat mining area. They are grain-supported and composed of phosphatic pellets, bioclasts (bones), non-phosphatic minerals, and cement. Geochemically, phosphorites contain high concentrations of P2O5 (23.59-28.36 wt.%) and CaO (40.85-44.35 wt.%), with low amounts of Al2O3 (0.23-0.51 wt.%), TiO2 (0.01-0.03 wt.%), Fe2O3 (1.14-2.28 wt.%), Na2O (0.37-1.19 wt.%), K2O (0.03-0.12 wt.%), and MnO (0.08-0.18 wt.%), suggesting the low contribution of the detrital material during their deposition. Moreover, they belong to contain enhanced U concentration (55-128 ppm). They are also enriched with Sr, Ba, Cr, V, and Zn and depleted in Th, Zr, and Rb, which strongly supports the low detrital input during the formation of the Hamadat phosphorites. The high Radioactivity of the studied phosphorites is probably due to the widespread occurrence of phosphatic components (e.g., apatite) that accommodate U in high concentrations. Gamma spectrometry based on NaI (Tl) crystal 3×3 has been used to measure occurring radionuclides in the phosphorite samples. The results indicate that the radioactive concentrations' average values of 226Ra, 232Th, and 40K are 184.18±9.19, 125.82±6.29, and 63.82±3.19 Bq Kg-1, respectively. Additionally, evaluations have been made of the radiological hazards. The calculated risk indicators exceeded the recommended national and world averages. The data obtained will serve as a reference for follow-up studies to evaluate the effectiveness of the Radioactivity of phosphatic materials collected from the Hamdat mine area.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Tório/análise , Radioisótopos de Potássio/análise , Monitoramento de Radiação/métodos , Compostos Férricos/análise
10.
Front Public Health ; 11: 1171209, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064659

RESUMO

Introduction: A lead-acrylic protective screen is suggested to reduce radiation exposure to the unexposed breast during mammography. The presence of toxic lead in its structure may harm the tissues with which it comes in contact. This study aimed to design a CdO-rich quaternary tellurite glass screen (C40) and evaluate its efficiency compared to the Lead-Acrylic protective screen. Methods: A three-layer advanced heterogeneous breast phantom designed in MCNPX (version 2.7.0) general-purpose Monte Carlo code. Lead acrylic and C40 shielding screens were modeled in the MCNPX and installed between the right and left breast. The reliability of the absorption differences between the lead acrylic and C40 glass were assessed. Results and discussion: The results showed that C40 protective glass screen has much superior protection properties compared to the lead acrylic protective screen. The amount of total dose absorbed in the unexposed breast for C40 was found to be much less than that for lead-based acrylic. The protection provided by the C40 glass screen is 35-38% superior to that of the Lead-Acrylic screen. The C40 offer the opportunity to avoid the toxic Pb in the structure of Lead-Acrylic material and may be utilized for mammography to offer superior radioprotection to Lead-Acrylic and significantly lower the dose amount in the unexposed breast. It can be concluded that transparent glass screens may be utilized for radiation protection purposes in critical diagnostic radiology applications through mammography.


Assuntos
Proteção Radiológica , Proteção Radiológica/métodos , Doses de Radiação , Método de Monte Carlo , Benchmarking , Reprodutibilidade dos Testes , Mamografia/métodos
11.
Materials (Basel) ; 16(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37109873

RESUMO

Solar cells in superstrate arrangement need a protective cover glass as one of its main components. The effectiveness of these cells is determined by the cover glass's low weight, radiation resistance, optical clarity, and structural integrity. Damage to the cell covers brought on by exposure to UV irradiation and energetic radiation is thought to be the root cause of the ongoing issue of a reduction in the amount of electricity that can be generated by solar panels installed on spacecraft. Lead-free glasses made of xBi2O3-(40 - x)CaO-60P2O5 (x = 5, 10, 15, 20, 25, and 30 mol%) were created using the usual approach of melting at a high temperature. The amorphous nature of the glass samples was confirmed using X-ray diffraction. At energies of 81, 238, 356, 662, 911, 1173, 1332, and 2614 keV, the impact of various chemical compositions on gamma shielding in a phospho-bismuth glass structure was measured. The evaluation of gamma shielding revealed that the results of the mass attenuation coefficient of glasses increase as the Bi2O3 content increases but decrease as the photon energy increases. As a result of the study conducted on the radiation-deflecting properties of ternary glass, a lead-free low-melting phosphate glass that exhibited outstanding overall performance was developed, and the optimal composition of a glass sample was identified. The 60P2O5-30Bi2O3-10CaO glass combination is a viable option for use in radiation shielding that does not include lead.

12.
Heliyon ; 9(3): e14274, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36950638

RESUMO

This study's primary objective is to provide the preliminary findings of novel research on the design of Indium (III) oxide-reinforced glass container that were thoroughly developed for the purpose of a nuclear material container for transportation and waste management applications. The shielding characteristics of an Indium (III) oxide-reinforced glass container with a certain elemental composition against the 60Co radioisotope was thoroughly evaluated. The energy deposition in the air surrounding the designed portable glass containers is measured using MCNPX general-purpose Monte Carlo code. Simulation studies were carried out using Lenovo-P620 workstation and the number of tracks was defined as 108 in each simulation phase. According to results, the indium oxide-doped C6 (TZI8) container exhibits superior protective properties compared to other conventional container materials such as 0.5Bitumen-0.5 Cement, Pb Glass composite, Steel-Magnetite concrete. In addition to its superiority in terms of nuclear safety, it is proposed that the source's simultaneous observation and monitoring, as well as the C6 (TZI8) glass structure's transparency, be underlined as significant advantages. High-density glasses, which may replace undesirable materials such as concrete and lead, provide several advantages in terms of production ease, non-toxic properties, and resource monitoring. In conclusion, the use of Indium (III) oxide-reinforced glass with its high transparency and outstanding protection properties may be a substantial choice in places where concrete is required to ensure the safety of nuclear materials.

13.
Heliyon ; 9(4): e14881, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37025762

RESUMO

We report the critical optical properties such as Average Visible Transmittance (AVT), colour, Color Rendering Index (CRI), and Correlated Color Temperature (CCT) of a multicomponent glass system with a nominal composition of 50TeO2-30B2O3-(20-x)Li2O-xCeO2 (x = 0,0.5,1,2,3,4,5,10,15,20 mol%). Various advanced theoretical approaches as well as calculations are utilized in terms of determining the optical properties of studied glasses. The maximum transmittance and AVT values of the glass system exceeded 80% and 79.59%, respectively. The colour coordinates are found extremely near to D65 and the achromatic point without CeO2 contribution. According to our results, the current system has a promising ability to be utilized for coloured window applications in terms of both AVT and colour with 2% CeO2 doping. Our results showed that, the CeO2 additive is able to move the glass colour straight into the red spectrum by shifting the transmittance spectrum to the long-wavelength portion of the visible spectrum. With 10% CeO2 doping, opacity in the visible area and permeability in the NIR region are obtained, and the CCT value changes from 5002 K to 2560 K. It can be concluded that a filter system with modifiable NIR or red optical characteristics may be produced through the CeO2 alterations in borotellurite glass systems.

14.
Heliyon ; 9(11): e21678, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027855

RESUMO

The Pseudomonas aeruginosa OG1 strain was used in the bacterial synthesis of MgSe compound nanoparticles. The obtained samples were subsequently shaped into nanocrystalline MgSe films, and their optical, structural, morphological, and electrical properties were assessed on glass and p-Si substrates. Structural and morphological characterizations showed that the fabricated thin film samples have a polycrystalline structure with high quality and uniform grain sizes. The MgSe films produced on glass substrates exhibit a direct spectral band gap of 2.53 eV, according to optical measurements. The Ag/MgSe/p-Si layered diode structure was fabricated using the produced MgSe nanoparticles and then characterized by electrical properties. Electrical measurements were carried out under these two conditions to assess the effects of dark and illumination conditions on the band dynamics of the heterostructure devices. Under illumination, the barrier height decreased while the interface density states distribution increased. These measurements showed that using bacterial-assisted grown MgSe nanocrystalline films, the developed Ag/MgSe/p-Si device structure exhibited a remarkable photoresponse and stable rectifying property. Green synthesis methods for the production of these nanocrystalline materials have the potential to offer low-cost alternatives for photosensitive applications.

15.
Front Public Health ; 11: 1136864, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36935709

RESUMO

Introduction: We report the breast and chest radiation dose assessment for mammographic examinations using a three-layer heterogeneous breast phantom through the MCNPX Monte Carlo code. Methods: A three-layer heterogeneous phantom along with compression plates and X-ray source are modeled. The validation of the simulation code is obtained using the data of AAPM TG-195 report. Deposited energy amount as a function of increasing source energy is calculated over a wide energy range. The behavioral changes in X-ray absorption as well as transmission are examined using the F6 Tally Mesh extension of MCNPX code. Moreover, deposited energy amount is calculated for modeled body phantom in the same energy range. Results and discussions: The diverse distribution of glands has a significant impact on the quantity of energy received by the various breast layers. In layers with a low glandular ratio, low-energy primary X-ray penetrability is highest. In response to an increase in energy, the absorption in layers with a low glandular ratio decreased. This results in the X-rays releasing their energy in the bottom layers. Additionally, the increase in energy increases the quantity of energy absorbed by the tissues around the breast.


Assuntos
Mamografia , Método de Monte Carlo , Mamografia/métodos , Doses de Radiação , Radiografia
16.
Nanomaterials (Basel) ; 13(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36770498

RESUMO

The main objective of this work is to recycle unwanted industrial waste in order to produce innovative nanocomposites with improved mechanical, tribological, and thermal properties for use in various industrial purposes. In this context, powder metallurgy (PM) technique was used to fabricate iron (Fe)/copper (Cu)/niobium carbide (NbC)/granite nanocomposites having outstanding mechanical, wear and thermal properties. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) examinations were used to investigate the particle size, crystal size, and phase composition of the milled samples. Additionally, it was investigated how different volume percentages of the NbC and granite affected the sintered specimens in terms of density, microstructure, mechanical and wear properties, and coefficient of thermal expansion (CTE). According to the findings, the milled powders included particles that were around 55 nm in size and clearly contained agglomerates. The results showed that the addition of 4 vol.% NbC and 8 vol.% granite nanoparticles caused a reduction in the Fe-Cu alloy matrix particle sizes up to 47.8 nm and served as a barrier to the migration of dislocations. In addition, the successive increase in the hybrid concentrations led to a significant decrease in the crystal size of the samples prepared as follows: 29.73, 27.58, 22.69, 19.95 and 15.8 nm. Furthermore, compared with the base Fe-Cu alloy, the nanocomposite having 12 vol.% of hybrid reinforcement demonstrated a significant improvement in the microhardness, ultimate strength, Young's modulus, longitudinal modulus, shear modulus, bulk modulus, CTE and wear rate by 94.3, 96.4, 61.1, 78.2, 57.1, 73.6, 25.6 and 61.9%, respectively. This indicates that both NbC and granite can actually act as excellent reinforcements in the Fe alloy.

17.
Heliyon ; 9(9): e19745, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809960

RESUMO

Magnesium ferrite (MgFe2O4) and polyethylene glycol (PEG) are materials known for their versatility in various applications. This study presents a comprehensive comparative analysis of the electrical conductivity and dielectric relaxation of nanostructured MgFe2O4 and its composites with PEG. Through experimentation, it was observed that incorporating PEG into MgFe2O4 did not lead to a high relative observed decrease or increase in electrical conductivity at room temperature. The study revealed that the composites maintained stable electrical behavior at room temperature, with a dielectric constant value of around 9 and a loss tangent value of around 0.1 at high frequency (around 7 MHz). The electron-hole hopping mechanism was identified as the underlying cause for the strong dielectric dispersion with frequency. The low dielectric loss and conductivity of the MgFe2O4 and PEG/ferrite composites make them promising candidates for high-frequency switching applications and microelectronic devices, particularly in scenarios where negligible eddy currents are essential. Additionally, complex impedance data analysis demonstrated that the capacitive and resistive properties of the composites are primarily attributed to grain boundary processes. This study provides a comprehensive analysis of the electrical and dielectric properties of MgFe2O4 and PEG composites and highlights their potential for many applications in materials science, particularly in electrical and electronic devices.

18.
Front Immunol ; 14: 1087397, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020549

RESUMO

The goal of the current study was to investigate the hormonal modulatory efficiency of hesperidin, through its regulatory potential of immunological, inflammatory, and/or antioxidant changes in on hyperthyroidism modeled adult female albino rats. Both normal and hyperthyroidism modeled rats (140-160g) were randomly divided into four groups (10 animals each) as follows: 1) healthy animals were daily ingested with saline for six weeks, and served as control group, 2) healthy animals were intraperitoneally injected with hesperidin (50 mg/kg/day) for a similar period, 3) hyperthyroidism-modeled animals without any treatment acted as positive control, and 4) hyperthyroidism-modeled animals were treated intraperitoneally with hesperidin for a similar period. The findings showed that hesperidin significantly modulated hyperthyroidism deteriorations, this was evidenced by a remarkable decline in serum T4, FT4, T3, FT3, TNF-α, IL1ß-, IL4-, IL-6, and IL-10 levels, with a minor increase in TSH and significant raise in CD4+ level. Similarly, valuable improvement was observed in the oxidative status; serum SOD, GPx, CAT, and GSH levels were dramatically enhanced, associated with remarkable drop in MDA and NO levels. Also, hesperidin demonstrated nephro-hepatoprotective and anti-atherogenic potential, this was achieved from the notable reduction in ALAT and ASAT activities as well as urea, creatinine, cholesterol, and triglyceride close to the corresponding values of healthy group. These findings were supported by histological and immunohistochemical ones that showed a notable decrease in the expression of the calcitonin antibody. In conclusion, hesperidin possesses anti-hyperthyroidism, immunoinflammatory regulatory, and antioxidant activities that evidenced from the improvement of physio-architecture of the thyroid gland, reduction of inflammation and restoration of the impaired oxidative stress. This effect might be mechanized through immunological, inflammatory, apoptotic, and/or antioxidant modulatory pathways.


Assuntos
Hesperidina , Hipertireoidismo , Animais , Feminino , Antioxidantes/farmacologia , Hesperidina/farmacologia , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Ratos
19.
Materials (Basel) ; 15(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36143691

RESUMO

This study aimed to investigate the interaction parameters of antioxidant molecules in some spices and vegetables with gamma radiation. At first, mass attenuation coefficients (MACs, cm2/g) of gingerol, rosmarinic acid, quercetin, curcumin, eugenol, piperine, allicin, and capsaicin molecules were determined at the photon energies (13-1332 keV) emitted from the radioactive isotopes Am-241, Ba-133, Co-60, and Cs-137 with the help of the EpiXS and WinXCOM programs. The smallest and largest MAC values were found as 1.20 and 8.48 cm2/g at 13 keV and 0.059 and 0.058 cm2/g at 1332 keV for eugenol and allicin, respectively. It was observed that both results support each other. Using the MAC values, the effective atomic number and electron density (Zeff and Neff) values of the molecules were derived. The Zeff values for gingerol and allicin were obtained in the range of 5.79-3.40 and 13.85-4.53, respectively. The variation of the buildup factors of antioxidants in the range of 0.015-15 MeV depending on the chemical composition and penetration depth were also examined. It was noticed that the photon accumulation was the lowest in allicin and the highest in gingerol and eugenol. The results obtained from this study will make an essential contribution to dose calculations in food irradiation studies.

20.
Materials (Basel) ; 15(12)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35744128

RESUMO

Natural radioactivity, radiological hazard, and petrological studies of Homrit Waggat granitic rocks, Central Eastern Desert, Egypt were performed in order to assess their suitability as ornamental stone. On the basis of mineralogical and geochemical compositions, Homrit Waggat granitic rocks can be subdivided into two subclasses. The first class comprises granodiorite and tonalite (I-type) and is ascribed to volcanic arc, whereas the second one includes alkali-feldspar granite, syenogranite, and albitized granite with high-K calc alkaline character, which is related to post-orogenic granites. 238U, 226Ra, 232Th, and 40K activities of natural radionuclides occurring in the examined rocks were measured radiometrically using sodium iodide detector. Furthermore, assessment of the hazard indices-such as: annual effective dose (AED) with mean values (0.11, 0.09, 0.07, 0.05, and 0.03, standard value = 0.07); gamma radiation index (Iγ) with mean values (0.6, 0.5, 0.4, 0.3, and 0.14, standard value = 0.5); internal (Hin) with mean values (0.6, 0.5, 0.4, 0.3, and 0.2, standard value = 1.0); external (Hex) index (0.5, 0.4, 0.3, 0.24, and 0.12, standard value = 1.0); absorbed gamma dose rate (D) with mean values (86.4, 75.9, 53.5, 43.6, and 20.8, standard value = 57); and radium equivalent activity (Raeq) with mean values (180, 154, 106.6, 90.1, and 42.7, standard value = 370)-were evaluated with the knowledge of the natural radionuclides. The result of these indices falls within the acceptable worldwide limits. Therefore, we suggest that these rocks are safe to be used in industrial applications.

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