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1.
Luminescence ; 35(4): 525-533, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31883298

RESUMO

Lithium borate (LB) glasses doped with dysprosium oxide (Dy2 O3 ) have been prepared by utilizing the conventional melt-quench technique. The prepared glass samples were exposed to 60 Co to check their dosimetric features and kinetic parameters. These features involve glow curves, annealing, fading, reproducibility, minimum detectable dose (MDD), and effective atomic number (Zeff ). Kinetic parameters including the frequency factors and activation energy were also determined using three methods (glow curve analysis, initial rise, and peak shape method) and were thoroughly interpreted. In addition, the incorporation of Dy impurities into LB enhanced the thermoluminescence sensitivity ~170 times. The glow from LB:Dy appeared as a single prominent peak at 190°C. The best annealing proceeding was obtained at 300°C for 30 min. Signal stability was reported for a period of 1 and 3 months with a reduction of 26% and 31%, respectively. The proposed glass samples showed promising dosimeter properties that can be recommended for personal radiation monitoring.


Assuntos
Boratos/química , Disprósio/química , Compostos de Lítio/química , Dosimetria Termoluminescente , Vidro/química , Cinética
2.
Luminescence ; 30(8): 1330-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25828828

RESUMO

We report the impact of dysprosium (Dy(3+)) dopant and magnesium oxide (MgO) modifier on the thermoluminescent properties of lithium borate (LB) glass via two procedures. The thermoluminescence (TL) glow curves reveal a single prominent peak at 190 °C for 0.5 mol% of Dy(3+). An increase in MgO contents by 10 mol% enhances the TL intensity by a factor of 1.5 times without causing any shift in the maximum temperature. This enhancement is attributed to the occurrence of extra electron traps created via magnesium and the energy transfer to trivalent Dy(3+) ions. Good linearity in the range of 0.01-4 Gy with a linear correlation coefficient of 0.998, fading as low as 21% over a period of 3 months, excellent reproducibility without oven annealing and tissue equivalent effective atomic numbers ~8.71 are achieved. The trap parameters, including geometric factor (µg), activation energy (E) and frequency factor (s) associated with LMB:Dy are also determined. These favorable TL characteristics of prepared glasses may contribute towards the development of Li2O-MgO-B2O3 radiation dosimeters.


Assuntos
Boratos/química , Disprósio/química , Vidro/química , Lítio/química , Compostos de Magnésio/química
3.
Radiography (Lond) ; 30(2): 567-573, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38286039

RESUMO

INTRODUCTION: Infection prevention and control (IPC) is crucial in safeguarding patient safety and minimizing the risk of healthcare-associated infections. AIM: The study investigated infection prevention and control measures for diagnostic imaging departments at governmental hospitals in the Gaza Strip, Palestine. METHODS: The study design was a cross-sectional analytical study. The sample included all radiographers (81) and radiologists (40) working at Al Shifa Medical Complex and European Gaza Hospital (EGH). Data was collected using an interview questionnaire (121) and an observation checklist. Data analysis was conducted using SPSS 26, and the result was significant (P < 0.05). RESULTS: Only 27.3 % of the participants revealed the availability of training courses for IPC. More than half of the participants received their last training sessions one year ago, and most of them attended five basic in-service training sessions related to IPC. Radiologists' and medical radiographers' knowledge and practice scores regarding IPC measures were 85.3 % and 61.7 %, respectively, and there were statistically significant differences between the participants' practice domain and their years of experience (p-value .014). There is inadequate hand hygiene among radiographers in the radiology department, and only 29 % of the staff washed their hands immediately upon arrival at the unit. The total score of the Hand Hygiene Self-Assessment Framework domains is almost equal at the two hospitals (280/500). The total score of the eight domains of the IPC Assessment Framework is 568.5/800 for Al Shifa Hospital and 516/800 for EGH, which indicates an intermediate IPC level. CONCLUSION: Efforts are needed to enhance the scope and quality of implementation and to concentrate on creating long-term plans to sustain and promote the existing IPC program activities. IMPLICATIONS FOR PRACTICE: Regular assessments should be conducted to monitor progress, identify gaps, and guide quality improvement efforts. Assessment feedback should be used to develop targeted interventions and continuously enhance IPC measures.


Assuntos
Hospitais Públicos , Controle de Infecções , Humanos , Estudos Transversais , Controle de Infecções/métodos , Oriente Médio , Diagnóstico por Imagem
4.
Sci Rep ; 14(1): 17700, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085245

RESUMO

The current study uses zinc oxide doping nanoparticles to investigate the radiation shielding properties of bismuth borate glass. Fourier transform infrared (FTIR) and X-ray diffraction (XRD) examined the structural characteristics of the current samples. In contrast, the optical properties were determined based on the absorption spectrum for current samples. Appraisal studies are carried out depending on the simulation capabilities of Phy-X/PSD software in conjunction with MCNP5 to achieve this goal. In addition, the neutron and charged particle shielding properties were evaluated theoretically. All glasses are amorphous, as confirmed by the XRD data, and the FTIR data showed several vibration bands and functional groups. The density showed rising from 5.981 to 6.433 g/cm3 with adding ZnO. The band gap values reduced from 2.831 to 2.091 eV for direct and 3.024 to 2.218 eV for indirect with adding ZnO. The investigations' findings demonstrate a strong agreement between the theoretical and simulation-derived estimates of the mass attenuation coefficient. The relative difference of MAC results lie in the range 0.106-2.941% for BBZ0, 0.105-4.348% for BBZ1, 0.105-3.398% for BBZ2, and 0.105-2.032% for BBZ3. The study's findings are valuable insights from thoroughly examining these parameters, which can potentially improve the radiation protection abilities of Bi2O3-B2O3-ZnO glasses. This study represents a significant step in developing more efficient and safer materials for gamma radiation shielding applications.

5.
Heliyon ; 9(7): e18309, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539187

RESUMO

The successful application of glass-based materials in a wide range of scientific fields depends on the associated physical, optical, thermal, and mechanical properties. This article investigate the structural, Physical, thermal, optical, and mechanical properties of Dy2O3, Y2O3 co-activated telluro-borate glass developed using the melt-quenching method. The glassy quality and the elements component of the specimens were observed using XRD and EDX analyses. The addition of Y2O3 rise the glass density from 2.956 to 3.303 g/cm3 the refractive index from 2.5 to 2.7. These changes are due to the increase in polarizability and non-bridging oxygen (NBO). The photoluminescence (PL) spectra revealed a broad peak at 550 nm and additional weak emission peaks at 573 and 664 nm, respectively. While the observed broader peak can be linked to the convolution of Bi3+ ions transitions corresponding to the non-centrosymmetric site respectively, the weak emission bands are due to 4F9/2 â†’ 6H13/2 and 4F9/2 â†’ 6H11/2 Dy3+ transitions. Hence, the low symmetrical features of both Bi3+ and Dy3+ ions were confirmed. The increase in the Vickers hardness of the glass from 536.7 to 1366.9 indicates the influence of Y2O3 addition on the mechanical properties of the glasses. The findings help to improve our understanding of the behaviour of the glass composition and its prospective applications in disciplines such as photonic, and laser optics.

6.
Appl Radiat Isot ; 189: 110408, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36029638

RESUMO

In the current study, we fabricated a series of boro-tellurite glass samples with a composition 10SrO-10Al2O3-10MoO3-(70-x)B2O3-xTeO2, where (x = 0, 17.5, 35, 52.5, and 70 mol%) via an ordinary melt-quench method. The glass structure was explored by X-ray diffraction (XRD), physical and structural properties. XRD results affirm the existence of two broad peaks, proving the amorphous state of the current glasses. The acquired results exhibit a linear relationship between the density, Poisson's ratio, and the addition of TeO2 amounts. The addition of TeO2 to the glass system shows a rise in glass stability and a reduction in packing density. Additionally, the values of mass attenuation coefficient (MAC) were determined experimentally within five energies (0.184, 0.280, 0.661, 0.710, and 0.810 MeV) from two radiation sources (166Ho and 137Cs). The (MAC)exp results were compared with XCOM values, and the compared values showed excellent compatibility. From the experimental results, many radiation shielding features involving half-value layer (HVL), mean free path (MFP), tenth value layer (TVL), and radiation protection efficiency (RPE) were computed. From the obtained results, it can be concluded that the TeSB4 sample has the highest stability and absorption for radiation, indicating the ability to use it as a radiation shielding substance.


Assuntos
Proteção Radiológica , Vidro/química , Proteção Radiológica/métodos , Difração de Raios X
7.
Nanomaterials (Basel) ; 12(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36234618

RESUMO

New series of YBCO ceramics samples doping with different oxides such as SiO2, WO3, Al2O3, and TiO2 were fabricated to study the ionizing radiation shielding properties. The structure and morphology were explored by X-ray diffraction (XRD) and scanning electron microscope (SEM). The shielding properties were investigated experimentally and theoretically to check the validity of the results. The investigated radiation shielding properties include the proton, neutron, and gamma-ray. The XRD results show the orthorhombic structure for all ceramics without any additional peaks related to WO3, SiO2, TiO2, and Al2O3. At the same time, the SEM results appear to have a significant differentiation in the granular behavior of all ceramics surfaces. The incorporation of WO3 to YBCO enhanced the ceramic density, whereas the addition of different oxides reduced the density for ceramic samples. This variation in density changed the radiation shielding results. The sample containing WO3 (YBCO-W) gives us better results in radiation shielding properties for gamma and neutron; the sample having Al2O3 (YBCO-Al) is superior in shielding results for charged particles. Finally, the possibility to use YBCO with various oxides in different ionizing radiation shielding fields can be concluded.

8.
Appl Radiat Isot ; 173: 109720, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33894469

RESUMO

The present work novelty pointed to fabricate new clay bricks doped with heavy minerals to be used in the building materials as a candidate for radiation shielding. The bricks were manufactured as (y)Iron mineral+ (1-y)clay, where y = 0, 0.1, 0.2 and 0.3 fractional weight. The prepared bricks' chemical composition and density were introduced to the MCNP-5 code to assess the prepared bricks' protection capacity. The simulated linear attenuation coefficient (LAC) was confirmed by comparing the simulated results with those calculated by the Phy-X/PSD program. We found that the simulated and calculated LAC were close together. The diff (%) between the MCNP-5 and Phy-X/PSD is in the range ±2% for all the fabricated bricks. The maximum LAC values occurred at 0.015 MeV, varied between 21.540 and 39.553 cm-1 for bricks N0 and N30. The lowest LAC achieved at 15 MeV varied between 0.068 and 0.090 cm-1. Bricks without heavy mineral addition have the lowest LAC values at all energies, ranging from 21.540 cm-1 to 0.068 cm-1, while bricks with 30 wt% heavy minerals have the highest LAC. The half-value layer (HVL) values decreased gradually with increasing the mineral ratio in the fabricated bricks. The thinner brick HVL achieved for the sample N 30 with 30 wt % heavy mineral, growing from 0.017 to 7.675 cm. The effective atomic number (Zeff) was reported, and we found that the minimum Zeff values equal to 14.006, 14.865, 15.705, and 16.394 for bricks N 0, N 10, N 20, N 30, respectively.


Assuntos
Argila , Raios gama , Minerais/química , Proteção Radiológica/instrumentação , Método de Monte Carlo
9.
Appl Radiat Isot ; 118: 375-381, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27894049

RESUMO

The effect of sodium as a co-dopant on the thermoluminescence (TL) properties of copper-doped zinc lithium borate (ZLB: Cu) subjected to Co-60 gamma radiation is reported in this study. TL intensity is enhanced with the introduction of sodium in ZLB: Cu. The obtained glow curve is simple with a single peak. The annealing procedure and the best heating rate for the proposed thermoluminescent dosimeter (TLD) are established, and the phosphor is reusable. The TL response within the dose range of 0.5-1000Gy is investigated. The results show that the thermal fading behaviour is improved significantly.

10.
Appl Radiat Isot ; 91: 126-30, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24929526

RESUMO

Lithium potassium borate (LKB) glasses co-doped with TiO2 and MgO were prepared using the melt quenching technique. The glasses were cut into transparent chips and exposed to gamma rays of (60)Co to study their thermoluminescence (TL) properties. The TL glow curve of the Ti-doped material featured a single prominent peak at 230 °C. Additional incorporation of MgO as a co-activator enhanced the TL intensity threefold. LKB:Ti,Mg is a low-Z material (Z(eff)=8.89) with slow signal fading. Its radiation sensitivity is 12 times lower that the sensitivity of TLD-100. The dose response is linear at doses up to 10(3) Gy. The trap parameters, such as the kinetics order, activation energy, and frequency factor, which are related to the glow peak, were determined using TolAnal software.

11.
Appl Radiat Isot ; 90: 258-60, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24858954

RESUMO

Radiation effects of photon irradiation in pure Photonic Crystal Fibres (PCF) and Flat fibres (FF) are still much less investigated in thermoluminescense dosimetry (TLD). We have reported the TL response of PCF and FF subjected to 6 MV photon irradiation. The proposed dosimeter shows good linearity at doses ranging from 1 to 4 Gy. The small size of these detectors points to its use as a dosimeter at megavoltage energies, where better tissue-equivalence and the Bragg-Gray cavity theory prevails.


Assuntos
Fibras Ópticas , Fótons , Doses de Radiação , Dióxido de Silício/química , Dióxido de Silício/efeitos da radiação , Dosimetria Termoluminescente/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Dosagem Radioterapêutica
12.
Appl Radiat Isot ; 78: 21-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23644162

RESUMO

New glasses Li2CO3-K2CO3-H3BO3 (LKB) co-doped with CuO and MgO, or with TiO2 and MgO, were synthesized by the chemical quenching technique. The thermoluminescence (TL) responses of LKB:Cu,Mg and LKB:Ti,Mg irradiated with 6 MV photons or 6 MeV electrons were compared in the dose range 0.5-4.0 Gy. The standard commercial dosimeter LiF:Mg,Ti (TLD-100) was used to calibrate the TL reader and as a reference in comparison of the TL properties of the new materials. The dependence of the responses of the new materials on (60)Co dose is linear in the range of 1-1000 Gy. The TL yields of both of the co-doped glasses and TLD-100 are greater for electron irradiation than for photon irradiation. The TL sensitivity of LKB:Ti,Mg is 1.3 times higher than the sensitivity of LKB:Cu,Mg and 12 times less than the sensitivity of TLD-100. The new TL dosimetric materials have low effective atomic numbers, good linearity of the dose responses, excellent signal reproducibility, and a simple glow curve structure. This combination of properties makes them suitable for radiation dosimetry.


Assuntos
Compostos de Lítio/química , Compostos de Lítio/efeitos da radiação , Metais/química , Metais/efeitos da radiação , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/métodos , Relação Dose-Resposta à Radiação , Elétrons , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Fótons , Doses de Radiação
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