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1.
Radiat Prot Dosimetry ; 199(20): 2506-2512, 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38126858

Zinc ferrite (ZnFe2O4) nanoparticles were synthesised via solution combustion method using urea as a fuel. The synthesised samples were characterised with various techniques. The cubic structure with Fd-3 m space group is confirmed by Powder X-ray Diffraction and Bragg's reflection. The crystallite size estimated from Scherrer's method was found to be 40 nm. The agglomerated irregular shape and sized surface morphology was confirmed by Scanning Electron Microscopy image. The direct energy band gap determined from Wood and Tauc's relation was found to be 5.25 eV. Using a NaI (Tl) detector and multi-channel analyser, the described sample was examined for X-ray and gamma ray shielding characteristics in the energy range of 0.081-1.332 MeV. The measured shielding values are in good agreement with the theory, however below 356 keV, there is a little variation of up to 10%. The current work offers up new possibilities for using this simple, affordable, effective and low temperature approach to create nanomaterials for X-ray and gamma ray shielding.


Nanoparticles , Zinc , Gamma Rays , X-Rays
2.
Radiat Prot Dosimetry ; 199(20): 2513-2519, 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38126859

In the current study, CeO2: Ag (0 and 11 mol) nanoparticles (NPs) were synthesized by solution combustion method using Aloevera extract as reducing agent. As-obtained NPs were characterized by standard techniques. Bragg's reflections confirm the formation of a single-phase cubic structure of CeO2:Ag NPs. Crystalline size is calculated using both the W-H plot and Scherrer's equation. Crystallite size found to decrease with increase in the dopant concentration. EDAX pattern confirmed the presence of Ce, O and Ag. Direct energy band calculated using Wood and Tauc's was found to be in the range of 2.9-2.2 eV for 0 and 11 mol, respectively. Fourier transformation infrared spectroscopy (FTIR) analysis confirmed the presence of the functional groups. Total shielding efficiency (SET) will give the best representation of EMI shielding properties. SET values calculated for a wide range of wavelengths are found to be as follows: near infrared (1.65 × 102 dB), mid infrared (9.78 × 101 dB) and far infrared (6.32 × 101 dB), followed by microwave region (MW) (6.46 × 101 dB), ultra-high frequency (UHF) (7.31 × 101 dB), very high frequency (VHF) (8.27 × 101 dB), high frequency (HF) (9.26 × 101 dB), medium frequency (MF) (1.02 × 102 dB), low frequency (LW) (1.12 × 102 dB), very low frequency (VLF) (1.22 × 102 dB), ultra-low frequency (ULF) (1.42 × 102 dB) and extremely low frequency (ELF) (1.52 × 102 dB). SET values of CeO2:Ag NPs are compared with other traditional materials and nanocomposites and found to be potential use in EMI shielding applications.


Nanocomposites , Nanoparticles , Protective Devices , Microwaves
3.
Radiat Prot Dosimetry ; 199(20): 2499-2505, 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38126863

Cerium oxide (CeO2) nanoparticles (NPs) exhibit a variety of properties, which have prompted researchers to explore CeO2 NPs in various applications such as biomedical, electrochemical, gas sensing and display applications. CeO2 NPs capabilities were impacted by the type of synthesis mechanism. CeO2 NPs were synthesized by solution combustion method using neem leaves extract as a reducing agent. The synthesized sample is characterized with different techniques. The Bragg reflections confirm the formation of cubic spinel structure. The surface morphology consists of agglomerated NPs. The direct energy band gap was found to be 2.9 eV. X-ray radiation absorption properties were studied within 1 keV-100GeV range. The results indicate that CeO2 NPs found to be potential in radiation applications.


Nanoparticles , X-Rays , Gamma Rays , Radiography
4.
Radiat Prot Dosimetry ; 199(20): 2455-2463, 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38126857

CeO2-NPs (nanoparticles) exhibit a variety of properties, which have prompted researchers to explore various applications, such as gas sensing, biomedical, Electromagnetic Interference (EMI) shielding, etc. Zn-doped CeO2-NPs with concentrations ranging from 7 to 11 mol were synthesised using Aloe vera extract as a reducing agent by the solution combustion method. As obtained, NPs were characterised by standard techniques. Braggs reflections confirm the formation of a single-phase cubic structure of CeO2Zn NPs. Crystalline size is calculated using both the W-H plot and the Scherrer equation, which were found to be 12 and 9 nm, respectively. The Energy-dispersive X-ray analysis (EDAX) pattern confirmed the presence of Ce, O and Zn. The direct energy band values are found to be decreasing from 3 to 2.87 eV with an increase in the doping concentration of Zn from 7 to 11 mol. Total shielding efficiency (SET) will give the best representation of shielding properties. The SEt values of CeO2Zn NPs are compared to those of other conventional materials and NP materials, finding significant applications in EMI shielding.


Electromagnetic Phenomena , Nanoparticles , Electromagnetic Radiation , Zinc
5.
Radiat Prot Dosimetry ; 199(20): 2520-2530, 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38126862

We investigated different decay modes such as heavy particle radioactivity (HPR), spontaneous fission (SF), alpha decay and beta-decay in superheavy (SH) region 104 ≤ Z ≤ 126. In HPR, different emissions from Zmin = 28 to maximum heavy particle (HP) emission up to Zmax = Z - 82 were considered. In the evaluation of Q-values, mass excess Weizsäcker-Skyrme 4+radial basis function (WS4+RBF) values were taken into account. The half-lives of cluster decay determined using modified generalised liquid drop model (MGLDM) and Coulomb and proximity potential model (CPPM) were in close agreement with the experimental results. The MGLDM produce less deviation compared with CPPM. The role of asymmetry effect, relative neutron excess, pairing effect and Coulomb effect on half-lives were studied. A band of neutron numbers from 193 to 200 shows extra stability against HPR. The HPR of 86Kr, 94Zr, 91Y and 96Mo is observed in the superheavy elements Z = 118, 122-124 and 126. The dominant decay mode identified is compared with SF, alpha and beta± decay, the majority of decay chains end with the lead nuclei, which is also evident in supernova and galaxy spectrum. This study could be useful in nuclear astrophysics.


Radioactivity , Neutrons , Azithromycin , Cell Nucleus , Half-Life
6.
Radiat Prot Dosimetry ; 199(20): 2428-2437, 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38126861

Over a century, shielding harmful electromagnetic radiations (EMR) and finding a suitable material, which can replace lead has become the major interest of researchers in this field. Herein, calcium-iron-chromium oxide nanocomposites with the different atomic ratios are synthesized using the solution combustion method. The as-obtained nanoparticles (NPs) are subjected to several structural and surface characteristics such as powder X-ray diffraction, scanning electron microscopy, elemental diffraction X-ray analysis, Fourier Transform Infrared Spectroscopy and UV-visible spectroscopy analysis were performed to confirm the successful synthesis. Furthermore, the EMR shielding of as-procured NPs is investigated and observed that the obtained NPs show good shielding properties.


Calcium , Nanocomposites , Iron , Electromagnetic Phenomena , Chromium , Electromagnetic Radiation
7.
Radiat Prot Dosimetry ; 199(20): 2447-2454, 2023 Dec 21.
Article En | MEDLINE | ID: mdl-38126870

The current study proposes an empirical formula for absorption buildup factors as a function of target thickness. The present formula produces absorption buildup factors of compounds and mixtures with simple inputs of linear attenuation coefficient (µ), tenth value layer (TVL) and half value layer (HVL) of interacting target for the atomic number region 29 < Z < 92 for the energies 0.2 MeV < E < 1.5 MeV. This method is used to compute the energy absorption buildup factors using HVL and TVL.

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