scholarly journals Development, Characterization and Valuable Use of Novel Dosimeter Film Based on PVA Polymer Doped Nitro Blue Tetrazolium Dye and AgNO3 for the Accurate Detection of Low X-ray Doses

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3140
Author(s):  
Saleh Alashrah ◽  
Yassine El-Ghoul ◽  
Faisal Muteb Almutairi ◽  
Mohammed Ahmed Ali Omer
Keyword(s):  
Structural Changes ◽  
Radiation Detection ◽  
Nitro Blue Tetrazolium ◽  
Diagnostic Radiology ◽  
Nanocomposite Films ◽  
X Rays ◽  
X Ray ◽  
Blue Tetrazolium ◽  
Accurate Detection ◽  
Low X

Currently, the uncontrolled exposure of individuals to X-rays during medical examinations represents a substantial danger that threatens both medical professionals and patients. Therefore, radiation dosimetry for low X-ray doses is a very important control of radiation practice in medical diagnostic radiology. In line with this, the current study proposes a valuable dosimeter-based PVA thin film doubly doped with silver nitrate salt and nitro blue tetrazolium dye. The nanocomposite film was prepared via a simple casting method and the different processing parameters were optimized. The performance of radiation detection was evaluated according to optical, chromic, chemical and structural changes after exposure to variable low X-ray doses (0, 2, 4, 10 and 20 mGy). The different film labels exhibited an excellent stability behavior in dark and light upon 30 days of storage. The UV-Vis spectrophotometric study showed a gradual increase in the maximum absorbance as a function of the dose and the corresponding response curve confirmed this linear variation (R = 0.998). A clear structural modification was recorded via X-ray diffraction (XRD) analysis revealing the increase in crystallinity with the level of the dose received by the nanocomposite films. Microscopic surface analysis via SEM assessments revealed a significant morphological change in PVA/Ag+/NBT films exposed to increased radiation doses and typical dendrites growing in needle- or tree-like microstructures appeared with a high X-ray dose. Finally, the nanocomposite films before and after irradiation were evaluated via a spectrocolorimetric study and the different CIELab coordinates, the color difference, as well as the color strength, showed a linear correlation with the intensity of the applied dose. This new dosimeter design could, therefore, provide a promising and efficient alternative for prompt and accurate detection of low X-rays doses in diagnostic radiology.

scholarly journals Synthesis and Characterization of a New Nanocomposite Film Based on Polyvinyl Alcohol Polymer and Nitro Blue Tetrazolium Dye as a Low Radiation Dosimeter in Medical Diagnostics Application

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1815
Author(s):  
Saleh Alashrah ◽  
Yassine El-Ghoul ◽  
Mohammed Ahmed Ali Omer
Keyword(s):  
Polyvinyl Alcohol ◽  
Nanocomposite Film ◽  
Radiation Detection ◽  
Medical Diagnostics ◽  
Linear Increase ◽  
Nitro Blue Tetrazolium ◽  
Diagnostic Radiology ◽  
Nanocomposite Films ◽  
X Ray ◽  
Blue Tetrazolium

Dosimetry is a field of increasing importance in diagnostic radiology. There has been a realization among healthcare professionals that the dose of radiation received by patients via modern medical X-ray examinations could induce acute damage to the skin and eyes. The present study highlights the synthesis of polyvinyl alcohol/nitro blue tetrazolium nanocomposite films (PVA/NBT) for radiation detection depending on chromic, optical, chemical and morphologic changes. First, we synthesized the nanocomposite film-based PVA doped with NBT and the different parameters of the preparation procedure were optimized. Then The films were exposed to different low X-ray doses on the scale of mGy level (0, 2, 4, 10 and 20 mGy). The sensitivity and the performance of the made composite films were evaluated via different characterization methods. Indeed, the response curve based on UV-Vis absorptions revealed a linear increase in absorbance with increased radiation doses (R = 0.998). FTIR analysis showed a clear chemical modification in recorded spectra after irradiation. X-ray diffraction assessment revealed clear structural changes in crystallinity after ionization treatment. SEM analysis showed a clear morphological modification of PVA/NBT films after irradiation. In addition, the prepared PVA/NBT films exhibited excellent pre- and post-irradiation stability in dark and light. Finally, the quantitative colorimetry study confirmed the performance of the prepared films and the different colorimetric coordinates, the total color difference (∆E) and the color strength (K/S) showed a linear increase with increasing X-ray doses. The made nanocomposite PVA/NBT film might offer promising potential for an effective highly sensitive medical dosimeter applied for very low doses in X-ray diagnostic radiology.

scholarly journals X-ray spectra and light curves of cooling novae and a nova like

2020 ◽  
Vol 499 (2) ◽  
pp. 3006-3018
Author(s):  
Bangzheng Sun ◽  
Marina Orio ◽  
Andrej Dobrotka ◽  
Gerardo Juan Manuel Luna ◽  
Sergey Shugarov ◽  
...  
Keyword(s):  
Light Curve ◽  
Accretion Rate ◽  
High Energy ◽  
Gravitational Energy ◽  
Light Curves ◽  
Clear Correlation ◽  
X Rays ◽  
High State ◽  
X Ray ◽  
Low X

ABSTRACT We present X-ray observations of novae V2491 Cyg and KT Eri about 9 yr post-outburst of the dwarf nova and post-nova candidate EY Cyg, and of a VY Scl variable. The first three objects were observed with XMM–Newton, KT Eri also with the Chandra ACIS-S camera, V794 Aql with the Chandra ACIS-S camera and High Energy Transmission Gratings. The two recent novae, similar in outburst amplitude and light curve, appear very different at quiescence. Assuming half of the gravitational energy is irradiated in X-rays, V2491 Cyg is accreting at $\dot{m}=1.4\times 10^{-9}{\!-\!}10^{-8}\,{\rm M}_\odot \,{\rm yr}^{-1}$, while for KT Eri, $\dot{m}\lt 2\times 10^{-10}{\rm M}_\odot \,{\rm yr}$. V2491 Cyg shows signatures of a magnetized WD, specifically of an intermediate polar. A periodicity of  39 min, detected in outburst, was still measured and is likely due to WD rotation. EY Cyg is accreting at $\dot{m}\sim 1.8\times 10^{-11}{\rm M}_\odot \,{\rm yr}^{-1}$, one magnitude lower than KT Eri, consistently with its U Gem outburst behaviour and its quiescent UV flux. The X-rays are modulated with the orbital period, despite the system’s low inclination, probably due to the X-ray flux of the secondary. A period of  81 min is also detected, suggesting that it may also be an intermediate polar. V794 Aql had low X-ray luminosity during an optically high state, about the same level as in a recent optically low state. Thus, we find no clear correlation between optical and X-ray luminosity: the accretion rate seems unstable and variable. The very hard X-ray spectrum indicates a massive WD.

Direct observation of various reaction pathways of arylnitrenes in different crystal environments caused by acid–base complex formation

2010 ◽  
Vol 66 (6) ◽  
pp. 647-661 ◽  
Author(s):  
Takahiro Mitsumori ◽  
Akiko Sekine ◽  
Hidehiro Uekusa ◽  
Yuji Ohashi
Keyword(s):  
Complex Formation ◽  
Structural Changes ◽  
Uv Light ◽  
Reaction Pathway ◽  
Crystal Form ◽  
X Rays ◽  
Acid Base ◽  
Base Complex ◽  
X Ray ◽  
Complex Crystals

The structures of reaction intermediates, arylnitrenes and their final products have been successfully analyzed by X-rays using acid–base complex formation. The acid–base complexes of 2-azidobenzoic acid (2a), 3-azidobenzoic acid (3a) and 4-azidobenzoic acid (4a) were made with dibenzylamine (db), N-benzyl-2-phenylethylamine (bp) and dicyclohexylamine (dc). For the complex crystals of (3a) and db (3a-db), and (4a) and db (4a-db) two forms of (I) and (II) were obtained. Eight types of complex crystals, (2a-db), (3a-db-I), (3a-db-II), (3a-dc), (4a-db-I), (4a-db-II), (4a-bp) and (4a-dc), suitable for X-ray analysis were obtained. When the crystals were irradiated with UV light at low temperatures, the reactions proceeded keeping the single-crystal form in the five crystals (2a-db), (3a-db-I), (3a-db-II), (3a-dc) and (4a-bp). Less than 25% of each azidobenzoic acids was transformed into an arylnitrene and dinitrogen. In three crystals the arylnitrenes produced gave new final products; 2,1-benzisoxazolone was observed for (2a-db) and trans-azobenzenes (i.e. dimerized nitrenes) were obtained for (3a-db-II) and (4a-bp). For (3a-db-I) and (3a-dc) the intermediate arylnitrenes were observed but did not transform to new products. All the structural changes were directly observed by X-ray analysis because the incomplete reactions occurred with retention crystallinity. The crystal environment, including the hydrogen bonding between the benzoic acid and the amine, places restrictions on the movement of the arylnitrene and influences the reaction pathway followed for conversion of the arylnitrene to its final product.

In Situ Monitoring of the Electrochemical Absorption of Deuterium into Palladium by X-Ray Diffraction using Synchrotron-Wiggler Radiation

1998 ◽  
Vol 524 ◽  
Author(s):  
D. D. Dominguez ◽  
P. L. Hagans ◽  
E. F. Skelton ◽  
S. B. Qadri ◽  
D. J. Nagel
Keyword(s):  
Structural Changes ◽  
National Laboratory ◽  
High Energy ◽  
Brookhaven National Laboratory ◽  
In Situ Monitoring ◽  
X Rays ◽  
X Ray ◽  
Β Phase ◽  
Metallic Sample

ABSTRACTWith low energy x-rays, such as those from a Cu x-ray tube, only the outer few microns of a metallic sample can be probed. This low penetrating power prohibits structural studies from being carried out on the interior of an electrode in an electrochemical cell because of absorption by the cell material, electrodes and the electrolyte. The work described in this paper circumvents this problem by utilizing high energy, high brightness x-rays produced on the superconducting wiggler beam line, X-17C, at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The penetrating power of the higher energy x-rays allowed Pd diffraction spectra to be obtained in-situ on a 1 mm diameter Pd wire cathode during electrolysis of heavy water. Moreover, the beam (28 × 28 μm in cross-section) allowed diffraction spectra to be acquired as a function of distance across the sample. Spectra were recorded in 50 μm steps from the edge of the Pd wire to its core. This was done at 2 minute intervals as a function of electrolysis time. The α-β phase transition induced in the Pd while deuterium was electrochemically absorbed was observed by monitoring the Pd-(422) diffraction peaks. Results allowed the diffusion rate and the diffusivity of deuterium atoms in the Pd wire to be determined. Other features of the structural changes associated with the absorption of deuterium into Pd are reported.

CONTINUUM X RAYS IN HIGHLY CHARGED ION-ATOM COLLISIONS

1996 ◽  
Vol 06 (03n04) ◽  
pp. 441-445
Author(s):  
K. KAWATSURA ◽  
T. HASEGAWA ◽  
N. TERAZAWA ◽  
S. ARAI ◽  
M. SATAKA ◽  
...  
Keyword(s):  
Energy Region ◽  
Heavy Ion ◽  
X Rays ◽  
X Ray ◽  
Radiative Processes ◽  
Gas Target ◽  
Electron Bremsstrahlung ◽  
Low X ◽  
Atom Collision ◽  
The Continuum

Continuous X rays produced by highly charged heavy ion-atom collisions have been studied experimentally. 2–5.5 MeV/u F, Si, S and Cl ions with zero or one electron were bombarded with a thin gas target of H 2 and He. Emitted X-ray spectra were measured by using a Si(Li) X-ray detector at 90°. The characteristic X rays and radiative electron capture X rays were observed clearly, which were superimposed on the continuum X rays. The continuum X rays can be well explained by two types of radiative processes: mainly quasi-free electron bremsstrahlung (QFEB), and partly atomic bremsstrahlung (AB). It should be noticed that QFEB is predominant at low X-ray energy region and AB at high X-ray energy region in highly charged heavy ion-atom collision process.

scholarly journals Family medicine residents’ skill levels in emergency chest X-ray interpretation

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Malak Al Shammari ◽  
Ali Hassan ◽  
Nouf AlShamlan ◽  
Sarah Alotaibi ◽  
Manar Bamashmoos ◽  
...  
Keyword(s):  
Family Medicine ◽  
Diagnostic Accuracy ◽  
General Practitioners ◽  
Diagnostic Radiology ◽  
X Rays ◽  
Diagnostic Confidence ◽  
X Ray ◽  
Chest X Ray ◽  
Radiology Residents ◽  
Family Medicine Residents

Abstract Background Family medicine physicians may encounter a wide variety of conditions, including acute and urgent cases. Considering the limited access to diagnostic investigations in primary care practice, chest X-ray remains the imaging modality of choice. The current study assessed the competency of family medicine residents in the interpretation of chest X-rays for emergency conditions and to compare it with that of diagnostic radiology residents, general practitioners, and medical interns. Methods An online survey was distributed to 600 physicians, including family medicine residents, medical interns, general practitioners, and diagnostic radiology residents. The study included some background information such as gender, years in practice, training type, interest in pulmonary medicine and diagnostic radiology, and having adequate training on the interpretation of chest X-rays. The survey had 10 chest X-ray cases with brief clinical information. Participants were asked to choose the most likely diagnosis and to rate their degree of confidence in the interpretation of the chest X-ray for each case. Results The survey was completed by 205 physicians (response rate = 34.2%). The overall diagnostic accuracy was 63.1% with a significant difference between family medicine and radiology residents (58.0% vs. 90.5%; P < 0.001). The COVID-19 pneumonia (85.4%) and pneumoperitoneum (80.5%) cases had the highest diagnostic accuracy scores. There was a significant correlation between the diagnostic confidence and accuracy (rs = 0.39; P < 0.001). Multivariable regression analysis revealed that being diagnostic radiology residents (odds ratio [OR]: 13.0; 95% confidence interval [CI]: 2.5–67.7) and having higher diagnostic confidence (OR: 2.2; 95% CI: 1.3–3.8) were the only independent predictors of achieving high diagnostic accuracy. Conclusion The competency of family medicine residents in the interpretation of chest X-ray for emergency conditions was far from optimal. The introduction of radiology training courses on emergency conditions seems imperative. Alternatively, the use of tele-radiology in primary healthcare centers should be considered.

scholarly journals HERA Phase I Limits on the Cosmic 21 cm Signal: Constraints on Astrophysics and Cosmology during the Epoch of Reionization

2022 ◽  
Vol 924 (2) ◽  
pp. 51
Author(s):  
Zara Abdurashidova ◽  
James E. Aguirre ◽  
Paul Alexander ◽  
Zaki S. Ali ◽  
Yanga Balfour ◽  
...  
Keyword(s):  
Theoretical Models ◽  
Hydrogen Gas ◽  
X Rays ◽  
X Ray ◽  
Upper Limits ◽  
Adiabatic Cooling ◽  
Radio Background ◽  
Early Galaxies ◽  
First Galaxies ◽  
Low X

Abstract Recently, the Hydrogen Epoch of Reionization Array (HERA) has produced the experiment’s first upper limits on the power spectrum of 21 cm fluctuations at z ∼ 8 and 10. Here, we use several independent theoretical models to infer constraints on the intergalactic medium (IGM) and galaxies during the epoch of reionization from these limits. We find that the IGM must have been heated above the adiabatic-cooling threshold by z ∼ 8, independent of uncertainties about IGM ionization and the radio background. Combining HERA limits with complementary observations constrains the spin temperature of the z ∼ 8 neutral IGM to 27 K 〈 T ¯ S 〉 630 K (2.3 K 〈 T ¯ S 〉 640 K) at 68% (95%) confidence. They therefore also place a lower bound on X-ray heating, a previously unconstrained aspects of early galaxies. For example, if the cosmic microwave background dominates the z ∼ 8 radio background, the new HERA limits imply that the first galaxies produced X-rays more efficiently than local ones. The z ∼ 10 limits require even earlier heating if dark-matter interactions cool the hydrogen gas. If an extra radio background is produced by galaxies, we rule out (at 95% confidence) the combination of high radio and low X-ray luminosities of L r,ν /SFR > 4 × 1024 W Hz−1 M ⊙ − 1 yr and L X /SFR < 7.6 × 1039 erg s−1 M ⊙ − 1 yr. The new HERA upper limits neither support nor disfavor a cosmological interpretation of the recent Experiment to Detect the Global EOR Signature (EDGES) measurement. The framework described here provides a foundation for the interpretation of future HERA results.

Dislocation Vector Analysis Method of Deep Dislocation Having C-Axis Segment in Diamond

2020 ◽  
Vol 1004 ◽  
pp. 519-524 ◽  
Author(s):  
Shinichi Shikata ◽  
Naoya Akashi
Keyword(s):  
Three Dimensional ◽  
Vector Analysis ◽  
X Rays ◽  
Analysis Method ◽  
Burgers Vector ◽  
X Ray ◽  
Semiconductor Crystals ◽  
Low X ◽  
X Ray Absorption ◽  
Geometrical Relationship

X-ray topography is an effective tool to investigate dislocations in semiconductor crystals. Due to low X-ray absorption coefficients of diamond, X-rays can penetrate deep into the crystal. Thus, deep three-dimensional (3D) dislocations are projected on two-dimension (2D) film, which makes dislocation analysis particularly challenging. Dislocation vectors from the films obtained using a set of the same diffraction vectors were identified using topographical and geometrical analyses. The depth and position of the dislocations in a crystal that was projected on a film were determined using geometrical relationship. The proposed analysis method was verified by analyzing several dislocations using four <404> diffraction films. The types of dislocation were identified through Burgers vector analysis.

Capillaries prepared from thin-walled heat-shrink poly(ethylene terephthalate) (PET) tubing for X-ray powder diffraction analysis

2006 ◽  
Vol 21 (4) ◽  
pp. 323-325 ◽  
Author(s):  
Joseph H. Reibenspies ◽  
Nattamai Bhuvanesh
Keyword(s):  
Ethylene Terephthalate ◽  
X Rays ◽  
X Ray ◽  
Long Wavelength ◽  
X Ray Scattering ◽  
Poly Ethylene Terephthalate ◽  
Thin Walled ◽  
Poly Ethylene ◽  
Low X ◽  
X Ray Absorption

Thin-walled heat-shrink poly(ethylene terephthalate) (PET) tubing is reported for use as an alternative for glass and Kapton® capillaries. PET tubing displays properties such as low X-ray absorption and smooth diffraction profiles. The 2.0 mm thin-walled (0.05 mm thick) and 0.5 mm thin-walled (0.02 mm thick) heat-shrink PET capillaries are 86% and 96% transparent to 1.54 Å X-rays. The low X-ray absorption and relatively smooth X-ray scattering profile of PET make it an ideal material for the home laboratory where the long wavelength, low flux, and low brilliance X-ray sources are employed. PET capillaries can be easily cut and manipulated and fixed to copper pins, which in turn can be employed in low-temperature and automated data collection routines.

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