Magnetic Studies Research Articles

Synthesis of multifunctional NiFe2O4-Zns-Ag nanocomposite for sunlight driven photocatalytic dye degradation and solar cells applications: Structural, magnetic and optical properties

This article focuses on the fabrication and investigation of the novel multifunctional NiFe2O4-Zns-Ag core-bi-shell nanocomposite and their magnetic optical properties. The nanocomposite was prepared by a simple co-precipitation method and characterized using various techniques such as XRD, SEM, TEM, UV–Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR) and VSM. The results showed that the nanocomposite had a spinel cubic structure with an average crystallite size of 29 nm. The SEM and TEM images revealed that the nanocomposite had a spherical shape with an average particle size of 61 nm. The optical study demonstrated that the nanocomposite had high absorption in the visible region, indicating its potential for photocatalytic applications. The magnetic study showed that the nanocomposite was superparamagnetic in nature, which could be useful in magnetic separation processes. Furthermore, the potential application of the nanocomposite in solar cells was explored by studying its optical absorption properties. Finally, the photocatalytic activity of the nanocomposite was evaluated using two different azoic dyes under sunlight irradiation. The results showed that the nanocomposite exhibited excellent photocatalytic activity, with a degradation efficiency of 96.22 % within 90 min. Overall, this study provides insights into the potential use of NiFe2O4-Zns-Ag nanocomposite as an efficient photocatalyst for environmental remediation.

Polymeric Manganese(II) Acetate Derivatives: Syntheses, Crystal Structures and Magnetic Properties

AbstractThree novel polymeric Mn(II) acetate derivatives, identified as {[Mn2.5(OH)(CH3COO)4] ⋅ 0.5CH3OH ⋅ 0.5CH3CN}n (1), {[Mn3(CH3CO O)6] ⋅ 0.5CH3CN}n (2) and {Mn1.5K(CH3COO)4}n (3), have been successfully prepared by systematically adjusting the ratio of reactants and using the 2‐mercapto‐5‐methyl‐1,3,4‐thiadiazole (Hmmt) as the template agent. These three complexes can be regarded as the different crystalline forms of Mn(CH3COO)2 under different reaction conditions. Single‐crystal X‐ray diffraction analyses revealed that 1 and 2 feature the unique three‐dimensional (3D) framework. For 3, it displays a 2D structure, which is further assembled to form a 3D extended network via the weak hydrogen bond interactions. Magnetic studies confirmed that 1 and 2 show antiferromagnetic interactions, and 1 displays a long‐range ordering phase below the critical temperature (Tc) of 7.8 K. In addition, magnetisation data collected for 1–2 yield low magnetic entropy changes, which can be attributed to the strong antiferromagnetic interactions among the Mn(II) centres.

Effects of opium tincture on gastrointestinal function and motility in healthy volunteers: A magnetic resonance imaging study.

Opioids inhibit motility and secretion of the gut and have been used for antidiarrheal treatment for centuries. However, the underlying mechanisms of opium tincture are not evident. To investigate the effects of opium tincture on gastrointestinal motility, intestinal volumes, and water content of different gut segments assessed by magnetic resonance imaging (MRI). Twenty healthy volunteers were included in a randomized, placebo-controlled, crossover study of 9 days of treatment with 30 drops of opium tincture per day. MRI was performed on day 1 (before treatment) and day 9 (during treatment). Measurements included assessments of gastric volume, gastric emptying, gastric motility, small bowel volume, small bowel water content, small bowel motility, colon volume, colon water content, and whole gut transit. Opium tincture delayed gastric emptying by a mean difference of 5.6 min [95% CI: 1.8-9.4], p = 0.004, and increased postprandial gastric meal volume (17-21%, p = 0.02). Small bowel endpoints did not change. Opium tincture delayed whole gut transit time (p = 0.027) and increased ascending colon volume by 59 mL [95% CI: 15-103], p = 0.004, and transverse colon volume by 48 mL [95% CI: 4-92], p = 0.027. T1-relaxation time of the descending colon chyme was decreased during opium treatment, indicating dryer feces (difference: -173 ms [95% CI: -336 -11], p = 0.03). Opium tincture induced changes in the stomach and colon in healthy volunteers. An improved understanding of how opioids affect gut functions may lead to a better understanding and optimized management of diarrhea.

Observation of Néel-type magnetic skyrmion in a layered non-centrosymmetric itinerant ferromagnet CrTe1.38

Magnetic skyrmions are nanoscale vortex-like magnetization textures that hold great promise for next-generation memory and spintronic devices. While extensive research has focused on discovering such localized spin textures in bulk magnets and multilayers with heavy metals, there is a growing interest in finding them in two-dimensional (2D) magnetic materials. In this research work, we report two distinct phases of the 2D CrxTey family: non-centrosymmetric CrTe1.38 and centrosymmetric CrTe0.96, with a Curie temperature of around 200 and 300 K, respectively. Detailed magnetic study indicates a prominent out-of-plane magnetic anisotropy in CrTe1.38. In contrast, CrTe0.96 exhibits a weak uniaxial magnetic anisotropy. Lorentz transmission electron microscopy shows that the spontaneous ferromagnetic ground state of CrTe1.38 consists of Néel skyrmions, whereas CrTe0.96 exhibits Bloch domain walls, consistent with their crystalline symmetries. This research expands the quasi-2D CrxTey family and opens up new avenues for exploring non-trivial spin structures and their potential applications in spintronic devices.

Chemical assessment of three octahedral Ni(II) complexes with heterocyclic acylpyrazolone ligand: Crystal structure, DFT-NBO analysis, Hirshfeld and Magnetic study

We have synthesized three novel mononuclear Nickel(II) coordination complexes [Ni(DMBPTMP)2(EtOH)2], [Ni(PCBPMP)2(DMF)(H2O)] and [Ni(PCBPTMP)2(DMSO)2] with σ-donating acylpyarazolone ligands. All the complexes have been comprehensively characterized via FTIR, UV–Vis, TGA, and Magnetic study. Additionally, single crystal X-ray diffraction analysis was successfully used to characterize the three complexes. The findings showed that the geometry around Ni(II) is slightly distorted octahedral in [Ni(DMBPTMP)2(EtOH)2], [Ni(PCBPMP)2(DMF)(H2O)] complexes and also in the centrosymmetric [Ni(PCBPTMP)2(DMSO)2] complex. In all the complexes the metal is bischelated by two pyrazolone molecules via carbonyl and benzoyl carbonyl oxygen donors, but with a different configuration of ligands. In addition to the experimental studies and spectroscopic characteristics, DFT computational analysis and Natural bonding orbital (NBO) analysis have been performed using a B3LYP/LANL2DZ basis set for the optimization. All three Ni(II) complexes give three distinct absorption transitions which has been proved by Electronic spectral analysis. A paramagnetic nature of the complex is confirmed through magnetic study. Utilising Hirshfeld surface analysis, intermolecular interactions of complexes were evaluated.

Nuclear Magnetic Resonance-Based Comparative Studies of Centrifugation, N2 flooding, CO2 Huff-n-Puff, and Spontaneous Imbibition for Oil Recovery in Lacustrine Shale in Eastern China

Nuclear Magnetic Resonance-Based Comparative Studies of Centrifugation, N₂ flooding, CO₂ Huff-n-Puff, and Spontaneous Imbibition for Oil Recovery in Lacustrine Shale in Eastern China

Amygdala activity after subchronic escitalopram administration in healthy volunteers: A pharmaco-functional magnetic resonance imaging study.

Selective serotonin reuptake inhibitors (SSRIs) are used for the treatment of several conditions including anxiety disorders, but the basic neurobiology of serotonin function remains unclear. The amygdala and prefrontal cortex are strongly innervated by serotonergic projections and have been suggested to play an important role in anxiety expression. However, serotonergic function in behaviour and SSRI-mediated neurobiological changes remain incompletely understood. To investigate the neural correlates of subchronic antidepressant administration. We investigated whether the 2- to 3-week administration of a highly selective SSRI (escitalopram) would alter brain activation on a task robustly shown to recruit the bilateral amygdala and frontal cortices in a large healthy volunteer sample. Participants performed the task during a functional magnetic resonance imaging acquisition before (n = 96) and after subchronic escitalopram (n = 46, days of administration mean (SD) = 15.7 (2.70)) or placebo (n = 40 days of administration mean (SD) = 16.2 (2.90)) self-administration. Compared to placebo, we found an elevation in right amygdala activation to the task after escitalopram administration without significant changes in mood. This effect was not seen in the left amygdala, the dorsomedial region of interest, the subgenual anterior cingulate cortex or the right fusiform area. There were no significant changes in connectivity between the dorsomedial cortex and amygdala or the subgenual anterior cingulate cortex after escitalopram administration. To date, this most highly powered study of subchronic SSRI administration indicates that, contrary to effects often seen in patients with anxiety disorders, subchronic SSRI treatment may increase amygdala activation in healthy controls. This finding highlights important gaps in our understanding of the functional role of serotonin.

Unpleasant emotions and task-unrelated thoughts and their associations with amygdala activity during emotional distraction: A functional magnetic resonance imaging study

Previous emotion regulation studies revealed that emotional distraction decreases unpleasant emotions. This study examined whether distraction tasks decrease unpleasant task-unrelated thoughts (TUTs) and unpleasant emotions when recalling stressful daily interpersonal events. Amygdala activity was examined to assess implicit emotional changes using functional magnetic resonance imaging (fMRI). The behavioral data of 20 university students (mean age: 20.35 ± 1.42 years; range: 18–24 years) and fMRI data of 18 students were examined. As an emotion induction procedure, participants initially freely recalled memories of daily stressful interpersonal events and then responded to a series of questions about their recalled memories presented on a monitor. In the distraction experiment, the questions were re-represented as an emotional stimulation; a distraction task (nonconstant or constant finger tapping) or rest condition was then performed, and ratings were given for attentional state, thought types conceived during the tasks, and emotional state. Decreases in unpleasant emotions and TUTs were defined as distraction effects. We found that unpleasant TUTs decreased in the nonconstant relative to rest condition (p < .05). Furthermore, increased right amygdala activation positively correlated with unpleasant emotions, and bilateral amygdala activation correlated with unpleasant TUTs only in the rest condition, indicating the existence of amygdala activation associated with unpleasant emotions and thoughts. However, such associations were not under nonconstant or constant conditions, indicating distraction effects. Notably, this study showed that emotional distraction can decrease the degree of unpleasant emotions and the occurrence of unpleasant thoughts regarding common daily emotions.

The need for further alcohol control research: A response to a functional magnetic resonance imaging study on alcohol warnings by Gallopel-Morvan etal.

The need for further alcohol control research: A response to a functional magnetic resonance imaging study on alcohol warnings by Gallopel-Morvan etal.

Structural, Morphological, and Magnetic Study of CoFe2-xDyxO4 (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1) Nanoparticles Prepared by Co-precipitation

Structural, Morphological, and Magnetic Study of CoFe2-xDyxO4 (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1) Nanoparticles Prepared by Co-precipitation

A structural, magnetic and colloidal stability study of uncoated and silica coated iron oxide samples prepared in two different surfactants

The discovery of new magnetic materials of interest in the biomedicine field is a relevant topic in current research. For years, our research group has been investigating the obtaining and study of nanostructured magnetic samples that behave superparamagnetically to enable their transport in living organisms. We present here a study that summarizes the structural characteristics, magnetic behavior and stability of two Fe3O4 samples synthesized by coprecipitation that were dispersed using two different surfactants (oleylamine, OL, and oleic acid, OA), and two others prepared from the previous ones by reaction with tetraethyl orthosilicate (TEOS). The relationships between the surfactant used in the synthesis, the presence of a certain maghemite (γ-Fe2O3) content, the influence of silica shell thickness and magnetic behaviour of all samples were systematically studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), Mössbauer spectroscopy and H vs. M loops. Rietveld refinements of the XRD profiles confirmed a partial oxidation of the non-silica-coated samples and FTIR spectra of the uncoated samples showed a very strong broad metal-oxygen band and additional sets of bands from the different organic chains of the two surfactants. Individual particles with a mean diameter of 7 and 9 nm were distinguished in TEM images of uncoated magnetic samples. Mössbauer data indicated the presence of non-stoichiometric magnetite in all samples, in agreement with XRD refinements. Magnetic measurements confirmed the superparamagnetic behavior of all the samples. Highest negative zeta potential values are found for the silica covered samples in both acidic and basic medium, being Fe3O4-AO@SiO2 the best suited for the purposes of its dispersibility in future applications. Low polydispersity index (PDI) values confirmed the best stability and dispersibility of all samples investigated in tetrahydrofuran (THF).

Synthesis, general physicochemical behaviour and magnetic studies of the macrocyclic bis-pyridine derivatives [TTDPzM(py)2]·2H2O (M = MnII, CoII, NiII)

In our extensive work on phthalocyanine-like macrocycles carrying peripherally attached strongly electron-withdrawing 1,2,5-thia/selenodiazol rings we recently reported on the FeII species of formula [TTDPzFe(py)2].2H2O (TTDPz = tetrakis(thiadiazole)porphyrazinato dianion). The present work deals with the synthesis and extended physicochemical studies of the series of related macrocycles [TTDPzM(py)2].2H2O (M = MnII, CoII, NiII). The diffractograms of three solid samples of the NiII complex [TTDPzNi(py)2]·2H2O, obtained from different synthetic procedures, indicate that the species is reproducibly obtained. All three samples are isomorphous with each other as shown by their X-ray powder diffractograms. Based on the comparison of the IR spectra of [TTDPzNi(py)2].2H2O and the related desolvated [TTDPzNi], the IR absorption peaks belonging to the pyridine molecules could be identified. The systematic presence of the two water molecules in all three species suggests that forms of contact do exist in the form of hydrogen bonds between them and the S and N atoms present peripherally in the thiadiazole groups of the macrocyclic units. As regard to the elimination of water, the thermograms (in inert atmosphere in the range 25–600 °C) indicate in all cases that loss of water occurs below 100 °C but loss of pyridine occurs over a broad range 100–300 °C for the MnII and CoII species whereas for the NiII complex it takes place in the narrow range 200–220 °C. In relation to the parallel series of metallophthalocyanines, i.e. [PcM] (M = MnII, FeII, CoII), it is noted that the NiII analog has not been reported in the literature and in a direct experiment it has been proved that [PcNi] heated in pyridine is obtained unchanged, the different behavior for the NiII TTDPz derivative due to the electron withdrawing effect of the external thiadiazole substituents, which makes favorable axial pyridine coordination in the complex. Completely insoluble in water, the triad of TTDPz derivatives are extremely low-soluble in non-donor or low donor solvents. This precluded any attempt to isolate single crystals for single-crystal X-ray work. Their UV–visible spectra show essential similarities in whatever organic solvent is used with clearly positioned Soret (300–400 nm) and Q-band absorptions (630–650 nm). Variable temperature magnetic susceptibility and magnetization studies reveal that the [TTDPzM(py)2].2H2O complexes all show paramagnetism with ground state spins of 3/2 (MnII), ½ (CoII) and 1 (NiII), supported by fitting the data to spin Hamiltonian formalism, vide infra. Comparisons are made with the magnetism of [PcM] analogues with key differences noted for M = NiII.

Study of Optoelectronic, Magnetic, and Thermoelectric Properties of Sr2XOsO6 (X = Y, Lu, Sc) Double Perovskites for Spintronic and Data Storage Devices

Advancement in electronic device miniaturization coupled with the precise control over their electromagnetic and transport properties, holds great promise for realizing practical quantum computing devices. Double perovskites, known for their stability, non-toxicity, and spin-polarized characteristics, are particularly appealing for spintronics applications. In this communication, we investigate the role of 6d-electrons of Os in regulating the magnetic properties in Sr2XOsO6 (X = Y, Lu, Sc) using theoretical methods with the WIEN2k code. The computed formation energies (-3.04, -2.91, and -2.82 eV) confirm the thermodynamic stability of these compositions. Analysis of the band structures and DOS exhibit ferromagnetic semiconducting character, elucidated through exchange constants and energies. This computation highlights the essential role of basic hybridization processes, crystal field effects, and exchange energy in generating ferromagnetic character driven by electronic spin. The analysis of optical behavior against photon energy (eV) reveals the maximum absorption in the UV region. Furthermore, the calculated values of σ/τ, ke/τ, S, χ, PF, and ZT in the temperature range of 200-800 K highlight the potential of these compounds for thermoelectric applications. This comprehensive analysis underscores the suitability of Sr2XOsO6 (X = Y, Lu, Sc) for advanced electronic and spintronic technologies.

2D mechanical representation of superconducting magnets: A comparative study of plane stress and plane strain

When approaching the mechanical design of a superconducting magnet, whenever possible the starting model is a 2D approximation. If rotational symmetry (solenoid-like winding) is present, the 2D representation is unique and contains no approximations. If, on the other hand, a non-axisymmetric system is opted for, the 2D representation is not unique and there are main options available, as plane stress, plane stress with thickness, plane strain and generalized plane strain. Considering z as the direction normal to the 2D plane, the plane stress option defines a stress state in which no normal or shear stresses perpendicular to the xy plane can occur (σz=σxz=σyz=0). In this option, deformation can occur in the thickness direction of the element, which will become thinner when stretched and thicker when compressed; it is generally used for objects with limited depth (thin objects).In contrast, plane strain refers to the fact that deformation can only occur in plane, which means that no out-of-plane deformation will occur (ϵz=ϵxz=ϵyz=0). The plane strain option is generally appropriate for structures of nearly infinite length, relative to their cross section, that exhibit negligible length changes under load. The “generalized plane strain” option imposes the axial strain equal to a constant value; this condition does not reproduce the real operating condition of the magnet and is therefore excluded. The “plane stress with thickness” uses the same equations as the plane stress option but, output quantities are given per unit length defined with thickness; therefore, it is again excluded from the comparison. Superconducting magnets, such as dipoles, do not fit neatly into any of the above options: they are far from thin but deform longitudinally under load. This work reports a comparative study of plane stress and plane strain in the specific case study of a dipole magnet.

Dielectric, magnetic and impedance spectroscopic studies of 0.9 Bi2/3Cu3Ti4O12–0.1 Bi3LaTi3O12 composite synthesized by semi-wet route

Dielectric, magnetic and impedance spectroscopic studies of 0.9 Bi2/3Cu3Ti4O12–0.1 Bi3LaTi3O12 composite synthesized by semi-wet route

Large reversible magnetocaloric effect in rare-earth molybdate RE2(MoO4)3 (RE: Gd and Tb) compounds

We report on the synthesis, structural, DC magnetic susceptibility studies on Gd2(MoO4)3 and Tb2(MoO4)3 polycrystals, prepared by conventional solid-state reaction method. Temperature and magnetic field (H) dependent magnetization and heat capacity measurements have been carried out to estimate the isothermal magnetic-entropy change (−ΔSm) and adiabatic temperature change (ΔTadi) in both rare-earth molybdates. No obvious long-range magnetic ordering can be found down to 2 K in both studied compounds. The estimated maximum value of –ΔSm at 3.5 K for 70 kOe is 31.1 J kg−1 K−1 and 16.7 J kg−1 K−1 in Gd2(MoO4)3 and Tb2(MoO4)3, respectively. Further, the calculated total-adiabatic temperature change for Gd2(MoO4)3 was 12.8 K, and Tb2(MoO4)3 has shown 9.8 K. The difference in the observed magnetocaloric and adiabatic temperature responses of Tb2(MoO4)3 compared to Gd2(MoO4)3 could be attributed to the presence of orbital angular moment of Tb3+ ions and relatively low-value of magnetization. Both the systems show a large magnetocaloric effect (MCE) (−ΔSm ∼ 12 J kg−1 K−1) even in low applied H (<20 kOe) attainable by a permanent magnet. Large magnetocaloric behaviour of Gd2(MoO4)3 and Tb2(MoO4)3 systems at a moderate field change along with very low electrical conductivity and the absence of thermal and magnetic field hysteresis in magnetization make them conducive to their use as promising magnetic refrigerants in the vicinity of liquid-helium temperatures.

448 - Brain functional alterations in patients with schizophrenia with comorbid metabolic syndrome treated with risperidone or clozapine: A resting-state functional magnetic resonance imaging study of regional homogeneity

448 - Brain functional alterations in patients with schizophrenia with comorbid metabolic syndrome treated with risperidone or clozapine: A resting-state functional magnetic resonance imaging study of regional homogeneity

Design of an Objective Magnetic Lens and Study of its Magnetic and Optical Properties in the Scanning Electron Microscope

The study's objective is to investigate the optical properties of the objective magnetic lens, which is considered as the most crucial part of the electron microscope. Three models of objective lenses (Snorkel, Pinhole, Gemini), equal in geometric dimensions were taken, and their optical properties, as well as their magnetic properties. It was found that the lens (P) achieved the best results, which were studied at a continuous excitation (NI=2000 A-t) and different acceleration voltages ranging from (8-16 kV), in addition to different values for the aperture angle (α). Then, we conducted an improvement on the selected lens by changing the width of the air gap between the poles (S) and studying the properties of the lens. We obtained better results for spherical (Cs=1.62 mm) and chromatic (Cc=1.84 mm) aberrations, focal length (fₒ=2.92 mm), as well as the highest value of the magnetic field (Bz=0.38 T) at an acceleration voltage (Vr=10000 V), excitation (NI=2000 A-t), and air gap width (S=5 mm), and the diameter of the electron probe (dp=11.25 nm) at an aperture angle (α=2 mrad).

Comparison of computer-aided quantitative measurement and physician visual assessment in the evaluation of intracranial atherosclerotic stenosis: a vessel wall magnetic resonance imaging study.

Intracranial atherosclerotic stenosis is a leading cause of ischemic stroke in China. Accurate assessment of intracranial atherosclerotic stenosis through imaging techniques is crucial for guiding therapeutic interventions and prognostic stratification. Vessel wall magnetic resonance imaging (VWMRI) has emerged as a reliable method for evaluating intracranial arterial vessels. With the advancement of technology, computer-aided quantitative measurement (CAQM) is increasingly used in imaging assessment. This study aimed to compare physician visual assessment (PVA) with CAQM in the VWMRI evaluation of intracranial atherosclerotic stenosis. This retrospective cross-sectional study consecutively enrolled patients diagnosed with intracranial atherosclerotic stenosis through imaging examinations at the Fourth Affiliated Hospital of China Medical University from December 2018 to December 2023. Clinical data were collected for analysis. Two radiologists independently and separately conducted CAQM and PVA on the VWMRI images of intracranial atherosclerotic stenosis patients. The imaging features evaluated encompassed stenosis severity, vessel wall remodeling, vessel wall thickening patterns, fibrous cap characteristics, lipid core ratio, and plaque enhancement degree. The study further assessed the discrepancies and concordance between the assessment results obtained from the two methods using paired sample t-tests, Wilcoxon signed-rank tests, and Cohen's kappa coefficient analysis. This study enrolled a total of 589 patients. The PVA time was shorter than CAQM (12.02±3.63 vs. 20.48±6.50 min). However, compared with digital subtraction angiography, the CAQM had a better area under the curve (0.88) than the PVA (0.80) in assessing luminal stenosis degree. The proportions of vessel wall remodeling (227/38.5%) and plaque surface irregularity (127/21.6%) evaluated by PVA were both lower than those by CAQM (438/74.4%, 171/29.0%). Meanwhile, no statistically significant differences were found in the patterns of wall thickening (P=0.12/0.39) and the proportion of plaque lipid core (P=0.65 and P=0.27), with good agreement between the two methods (K=0.67/0.85, K=0.97/0.94). While there were no statistical differences in the assessment of plaque enhancement degree in specific arteries (middle cerebral artery and basilar artery) (n=77/36, P=0.08/0.21), an overall statistical difference was observed (n=113, P=0.03). Additionally, there was poor agreement in assessing plaque enhancement degree, with Cohen's kappa values of 0.13 (-0.05 to 0.32) and 0.16 (-0.06 to 0.39). This study revealed disparities between PVA and CAQM in the evaluation of intracranial atherosclerotic stenosis of VWMRI. CAQM is recommended for assessing stenosis degree, vessel wall remodeling, and fibrous cap characteristics. However, PVA is suggested to assess wall thickening patterns and lipid core ratio to expedite diagnosis. Further research is needed to validate CAQM's superiority in evaluating plaque enhancement degrees.

314 - The Development of Learning Materials for Preparing Virtual Patients for Magnetic Resonance Imaging Study Using Virtual Reality Technology for Students of Radiological Technology

314 - The Development of Learning Materials for Preparing Virtual Patients for Magnetic Resonance Imaging Study Using Virtual Reality Technology for Students of Radiological Technology