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1.
Heliyon ; 9(6): e16461, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37292306

RESUMO

In this research, Fe3O4@HZSM-5 magnetic nanocomposite was synthesized via a coprecipitation method for metronidazole (MNZ) degradation from aqueous solutions under ultrasonic irradiation which showed superb sonocatalytic activity. The synthesized magnetite nanocomposite was characterized by using field-emission scanning electron microscope-energy dispersive X-ray Spectroscopy, (FESEM-EDS), Line Scan, Dot Mapping, X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and Brunauer-Emmett-Teller (BET). To investigate the sonocatalytic activity of the Fe3O4@HZSM-5 magnetite nanocomposite, the sonocatalytic removal conditions were optimized by evaluating the influences of operating parameters like the dosage of catalyst, reaction time, pH, the concentration of H2O2, MNZ concentration, and pH on the MNZ removal. The MNZ maximum removal efficiency and TOC at reaction time 40 min, catalyst dose 0.4 g/L, H2O2 concentration 1 mM, MNZ initial concentration 25 mg/L, and pH 7 were achieved at 98% and 81%, respectively. Additionally, the MNZ removal efficiency in the real wastewater sample under optimal conditions was obtained at 83%. The achieved results showed that using Langmuir-Hinshelwood kinetic model KL-H = 0.40 L mg-1, KC = 1.38 mg/L min) can describe the kinetic removal of the process. The radical scavenger tests indicated that the major reactive oxygen species were formed by hydroxyl radicals in the Sono-Fenton-like process. Evaluation of the nanocomposite reusability showed an 85% reduction in the MNZ removal efficiency after seven cycles. Based on the results, it can be concluded that Fe3O4@HZSM-5 were synthesized as magnetic heterogeneous nano-catalysts to effectively degrade MNZ, and the observed stability and recyclability demonstrated that Fe3O4@HZSM-5 was promising for the treatment of wastewater contaminated with antibiotics.

2.
Am J Neurodegener Dis ; 12(2): 42-84, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213710

RESUMO

OBJECTIVE: Magnetic resonance imaging (MRI) of the brain or spine examines the findings as well as the time interval between the onset of symptoms and other adverse effects in coronavirus disease that first appeared in 2019 (COVID-19) patients. The goal of this study is to look at studies that use neuroimaging to look at neurological and neuroradiological symptoms in COVID-19 patients. METHODS: We try to put together all of the research on how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes neurological symptoms and cognitive-behavioral changes and give a full picture. RESULTS: We have categorized neuroimaging findings into subtitles such as: headache and dizziness; cerebrovascular complications after stroke; Intracerebral Hemorrhage (ICH); Cerebral Microbleeds (CMBs); encephalopathy; meningitis; encephalitis and myelitis; altered mental status (AMS) and delirium; seizure; neuropsychiatric symptoms; Guillain-Barre Syndrome (GBS) and its variants; smell and taste disorders; peripheral neuropathy; Mild Cognitive Impairment (MCI); and myopathy and myositis. CONCLUSION: In this review study, we talked about some MRI findings that show how COVID-19 affects the nervous system based on what we found.

3.
Am J Nucl Med Mol Imaging ; 12(3): 99-105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874294

RESUMO

We performed this study to evaluate the correlation between Body Mass Index (BMI) and Exposure Rate (ER) of hyperthyroid patients treated with iodine-131 so that in case of any relationship, we can improve the prescribed dose for the treatment of hyperthyroid patients and its side effects on the body and the environment. In this analytical and cross-sectional study, 30 patients with hyperthyroidism treated with liquid iodine-131 were randomly selected. We recorded demographic indicators (age, height, and weight) and ER. Patients were treated with the activity of 8-29 mCi (mean 14.4 mCi) oral I-131. The external radiation of patients was measured from a distance of one meter parallel to the patient's thyroid gland at intervals of 6 to 24 hours post-iodine-131 administration. ER measurements and other acquired data were statistically analyzed by R software and its methods. Data were normalized using the Shapiro method, and due to the non-normality of the data in the correlation test, the Spearman method was used. The measurements of this study represent two main findings: 1. There is a significant relationship between ER and iodine-131 activity because the observed significance level (P-value =0.002) is smaller than the predicted error value (0.01). 2. There is no significant relationship between ER and BMI because the observed significance level (P-value =0.082) is greater than the predicted error value (0.05). The present study's findings show a negative relationship between BMI and ER. Still, since the P-value is more than 0.05, this relationship is not statistically significant.

4.
MethodsX ; 7: 101118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204655

RESUMO

Azo dyes are the largest group of synthetic organic dyes which containing the linkage C-N[bond, double bond]N-C and used in various industries such as textile industries leather articles, and some foods. Azo dyes are resistant compounds against the biodegradation processes. The purpose of this research was hybrid UV/COP advanced oxidation process using ZnO as a catalyst immobilized on a stone surface for degradation of acid red 18 (AR18) Dye. In the hybrid process using some parameters such as the dye initial concentration, pH, contact time and catalyst concentration, the process efficiency was investigated. In order to the dye removal, the sole ozonation process (SOP), catalytic ozonation process (COP) and photocatalytic process (UV/ZnO) were used. The ZnO nanoparticles were characterized by XRD, SEM and TEM analyses.  The maximum dye removal was achieved 97% at the dye initial concentration 25 mg/L, catalyst concentration 3 g/L, contact time 40 min and pH 5. As a real sample, the Yazdbaf textile factory wastewater was selected. After that, the physicochemical quality was evaluated. As well as, in the optimal conditions, the AR18 dye removal efficiency was achieved 65%. The kinetic results demonstrated that the degradation reaction was fitted by pseudo-first-order kinetic. The UV/COP hybrid process had high efficiency for removal of resistant dyes from the textile wastewater. Advantages of this technique were as follows:•ZnO nanoparticles were synthesized as catalyst by thermal method and were immobilized on the stones.•pH changes had no significant effect on the removal efficiency.•In the kinetic studies, the decomposition reaction followed pseudo-first order kinetic.

5.
MethodsX ; 7: 74-81, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31908987

RESUMO

Herein, magnetically separable CuFe2O4@methyl cellulose (MC) as a novel magnetic nanobiocomposite photocatalyst was synthesized with a facile, rapid, green, and new microwave-assisted method. After that, CuFe2O4@MC was characterized with FESEM, EDS, FT-IR, XRD, TGA, and VSM techniques. To measure CuFe2O4@MC photocatalytic activity, ciprofloxacin (CIP) removal ability of CuFe2O4@MC was investigated under the conditions such as initial CIP concentrations (3, 5, 7, and 9 mg/L), pHs (3, 7, and 11), photocatalyst loadings (0.025, 0.05, 0.1, 0.2, 0.3, and 0.4 g), and irradiation time (15, 30, 45, 60, 75, and 90 min). Kinetic process was evaluated with the pseudo-first order and the Langmuir-Hinshelwood models. CIP concentration was measured with high performance liquid chromatography (HPLC). The maximum CIP removal efficiency in the optimal conditions which contained pH = 7, CIP initial concentration of 3 mg/L, photocatalyst loading of 0.2 g, and at irradiation time 90 min was achieved 72.87 % and 80.74 % from real and synthetic samples, respectively. Also, COD removal efficiency in the optimal conditions was achieved 68.26 %. Furthermore, the CuFe2O4@MC reusability and chemical stability were examined and 73.78 % of CIP was degraded after the fourth cycle. Advantages of this technique were as follows: •CuFe2O4@MC as a new nanobiomagnetic photocatalyst was synthesized with a facile, fast, and green method and were characterized with FESEM, EDS, FT-IR, XRD, TGA, and VSM techniques.•Ferromagnetic property and pure-phase spinel ferrites of CuFe2O4@MC were confirmed and significant photocatalytic activity of CuFe2O4@MC was observed.•Easily gathering, reusability and good chemical stability were interests of this nanobiomagnetic photocatalyst.

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