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1.
Environ Pollut ; 334: 122059, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37390913

RESUMEN

A ternary hetero-junction was prepared by anchoring ZnO@CoFe2O4 (ZCF) on activated carbon (AC) and employed as a UV-assisted peroxymonosulfate (PMS) activator to boost the degradation of diazinon (DZN) pesticide. The structure, morphology, and optical properties of the ZCFAC hetero-junction were characterized through a series of techniques. The highest degradation efficiency of DZN (100% in 90 min) was achieved by the PMS-mediated ZCFAC/UV system, superior to other single or binary catalytic systems due to the strong synergistic effect between ZCFAC, PMS, and UV. The operating reaction conditions, synergistic effects, and the possible pathways of DZN degradation were investigated and discussed. Optical analysis showed that the band-gap energy of the ZCFAC hetero-junction not only enhanced the absorption of UV light but also reduced the recombination of photo-induced electron/hole pairs. Both radical and non-radical species (HO•, SO4•-, O2•-, 1O2, and h+) took part in the photo-degradation of DZN, assessed by scavenging tests. It was found that AC as a carrier not only improved the catalytic activity of CF and ZnO nanoparticles and conferred high stability for the catalyst but also played a crucial role in accelerating the catalytic PMS activation mechanism. Moreover, the PMS-mediated ZCFAC/UV system showed good reusability, universality, and practical applicability potential. Overall, this work explored an efficient strategy for the best use of hetero-structure photo-catalysts towards PMS activation to achieve high performance in decontaminating organic compounds.


Asunto(s)
Plaguicidas , Óxido de Zinc , Carbón Orgánico , Compuestos Orgánicos , Diazinón , Peróxidos/química
2.
Nanotechnology ; 34(27)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-36996779

RESUMEN

Infectious diseases such as novel coronavirus (SARS-CoV-2), Influenza, HIV, Ebola, etc kill many people around the world every year (SARS-CoV-2 in 2019, Ebola in 2013, HIV in 1980, Influenza in 1918). For example, SARS-CoV-2 has plagued higher than 317 000 000 people around the world from December 2019 to January 13, 2022. Some infectious diseases do not yet have not a proper vaccine, drug, therapeutic, and/or detection method, which makes rapid identification and definitive treatments the main challenges. Different device techniques have been used to detect infectious diseases. However, in recent years, magnetic materials have emerged as active sensors/biosensors for detecting viral, bacterial, and plasmids agents. In this review, the recent applications of magnetic materials in biosensors for infectious viruses detection have been discussed. Also, this work addresses the future trends and perspectives of magnetic biosensors.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Enfermedades Transmisibles , Ebolavirus , Infecciones por VIH , Fiebre Hemorrágica Ebola , Gripe Humana , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , Fenómenos Magnéticos
3.
Chemosphere ; 287(Pt 3): 132273, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34563773

RESUMEN

In this research, the potential of bismuth chromate (BCO), a new bismuth-based semiconductor belongs to the family of Bi2XO6 (X = Mo, W, or Cr), was introduced by a novel 1D/2D structure consist of BCO nanobelts and N2-freezed ultra-wrinkled graphitic carbon nitride (N-CN) nanosheets. To enhance intimate contact between BCO and N-CN (BCO/N-CN composite), surface oxygen vacancy (VO) was created as an efficient electron transfer highway using a simple alkaline-treatment-assisted method. Various characterization techniques, including XRD, FT-IR, EPR, FE-SEM, TEM, BET, DRS, PL, EIS, and photocurrent transient analyses were conducted to elucidate the physicochemical aspects of catalysts. The synthesized catalysts were subjected to levofloxacin (LVFX) photodegradation and optimum conditions were found under LED irradiation. Under optimum conditions, about 92.5% of LVFX was catalytically degraded over VO-rich BCO/N-CN heterojunction after 120 min of reaction, which was 2.3 folds higher than that of VO-free composite. The obtained heterojunction maintained superior performance after five consecutive runs with no noticeable changes in the XRD and FT-IR patterns, demonstrating the high stability of synthesized nanocomposite. Thus, the proposed interfacial engineering in this study opens new insight for ameliorating the insufficient interfacial contact between components of heterojunctions. This study not only presents a new bismuth-based photocatalyst for antibiotic degradation but also sheds light on the charge migration behavior in favor of efficient Z-type heterojunction.


Asunto(s)
Bismuto , Oxígeno , Antibacterianos , Semiconductores , Espectroscopía Infrarroja por Transformada de Fourier
4.
BMC Infect Dis ; 21(1): 1185, 2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34823478

RESUMEN

BACKGROUND: The first confirmed cases of COVID-19 in Iran were reported in Qom city. Subsequently, the neighboring provinces and gradually all 31 provinces of Iran were involved. This study aimed to investigate the case fatility rate, basic reproductive number in different period of epidemic, projection of daily and cumulative incidence cases and also spatiotemporal mapping of SARS-CoV-2 in Alborz province, Iran. METHODS: A confirmed case of COVID-19 infection was defined as a case with a positive result of viral nucleic acid testing in respiratory specimens. Serial interval (SI) was fitted by gamma distribution and considered the likelihood-based R0 using a branching process with Poisson likelihood. Seven days average of cases, deaths, doubling times and CFRs used to draw smooth charts. kernel density tool in Arc GIS (Esri) software has been employed to compute hot spot area of the study site. RESULTS: The maximum-likelihood value of R0 was 2.88 (95%, CI: 2.57-3.23) in the early 14 days of epidemic. The case fatility rate for Alborz province (Iran) on March 10, was 8.33% (95%, CI:6.3-11), and by April 20, it had an increasing trend and reached 12.9% (95%,CI:11.5-14.4). The doubling time has been increasing from about two days and then reached about 97 days on April 20, 2020, which shows the slowdown in the spread rate of the disease. Also, from March 26 to April 2, 2020 the whole Geographical area of Karj city was almost affected by SARS-CoV-2. CONCLUSIONS: The R0 of COVID-19 in Alborz province was substantially high at the beginning of the epidemic, but with preventive measures and public education and GIS based monitoring of the cases,it has been reduced to 1.19 within two months. This reduction highpoints the attainment of preventive measures in place, however we must be ready for any second epidemic waves during the next months.


Asunto(s)
COVID-19 , Epidemias , Sistemas de Información Geográfica , Humanos , Irán/epidemiología , Funciones de Verosimilitud , SARS-CoV-2
5.
Diabetol Metab Syndr ; 12: 57, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32641974

RESUMEN

BACKGROUND: Diabetes mellitus (DM) and cardiovascular disease (CVD) are present in a large number of patients with novel Coronavirus disease 2019 (COVID-19). We aimed to determine the risk and predictors of in-hospital mortality from COVID-19 in patients with DM and CVD. METHODS: This retrospective cohort study included hospitalized patients aged ≥ 18 years with confirmed COVID-19 in Alborz province, Iran, from 20 February 2020 to 25 March 2020. Data on demographic, clinical and outcome (in-hospital mortality) data were obtained from electronic medical records. Self-reported comorbidities were classified into the following groups: "DM" (having DM with or without other comorbidities), "only DM" (having DM without other comorbidities), "CVD" (having CVD with or without other comorbidities), "only CVD" (having CVD without other comorbidities), and "having any comorbidity". Multivariate logistic regression models were fitted to quantify the risk and predictors of in-hospital mortality from COVID-19 in patients with these comorbidities. RESULTS: Among 2957 patients with COVID-19, 2656 were discharged as cured, and 301 died. In multivariate model, DM (OR: 1.62 (95% CI 1.14-2.30)) and only DM (1.69 (1.05-2.74)) increased the risk of death from COVID-19; but, both CVD and only CVD showed non-significant associations (p > 0.05). Moreover, "having any comorbidities" increased the risk of in-hospital mortality from COVID-19 (OR: 2.66 (95% CI 2.09-3.40)). Significant predictors of mortality from COVID-19 in patients with DM were lymphocyte count, creatinine and C-reactive protein (CRP) level (all P-values < 0.05). CONCLUSIONS: Our findings suggest that diabetic patients have an increased risk of in-hospital mortality following COVID-19; also, lymphocyte count, creatinine and CRP concentrations could be considered as significant predictors for the death of COVID-19 in these patients.

6.
Immunopharmacol Immunotoxicol ; 42(1): 1-8, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31793820

RESUMEN

Inflammation is a physiological process essential for maintaining homeostatic mechanisms in human, but however, exaggerated inflammatory responses are closely related to many chronic diseases. Cadmium (Cd) is a heavy metal with high toxicity when present in food, water and air has the potential of eliciting inflammatory reactions, with a major health risk to human. This review aimed to elucidate on the major routes of Cd exposure, the main organs affected by the exposure, the degree of toxicity as well as the roles of the toxic effects on the immune system which results to inflammatory responses. Immune modulation by Cd may cause serious adverse health effects in humans. Various studies have highlighted the ability of Cd as an environmental pollutant involved in the modulation of the innate, adaptive and mucosal immune responses in relations to the release of chemokine, gene expression, and susceptibility to microbial infections.


Asunto(s)
Inmunidad Adaptativa/efectos de los fármacos , Cadmio/toxicidad , Contaminantes Ambientales/toxicidad , Inmunidad Innata/efectos de los fármacos , Inmunidad Mucosa/efectos de los fármacos , Infecciones , Animales , Quimiocinas/inmunología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Infecciones/inducido químicamente , Infecciones/inmunología , Infecciones/patología , Inflamación/inducido químicamente , Inflamación/inmunología , Inflamación/patología
7.
J Environ Manage ; 250: 109472, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31521031

RESUMEN

In the present study, ZnO nanoparticles were anchored on a magnetic core/shell structure (SiO2@Fe3O4) to perpetrate ZnO@SiO2@Fe3O4 and then coupled with UV light as a heterogeneous nanocatalyst for activating peroxymonosulfate (PMS) into diazinon (DZ) degradation. Several techniques like XRD (X-ray diffraction), BET (Brunaeur, Emmett and Teller), TEM (Transmission electron microscope), FESEM (Field emission-scanning electron microscope) coupled with EDS (Energy Dispersive X-ray Spectrometer), PL (photoluminescence), VSM (Vibrating Sample Magnetometer) and UV-vis diffuse reflectance spectroscopy (DRS) were applied for identification of catalyst features. A possible mechanism for PMS activation and DZ degradation was proposed in details. The effect of solution pH, various concentrations of catalyst, PMS and DZ, quenching agents, different chemical oxidants and co-existing anions was assessed as operating factors to determine the optimum conditions. PMS decomposed effectively in coupling with ZnO@SiO2@Fe3O4 and UV. At optimal conditions, over 95 and 56% of DZ and TOC were removed during 60 min reaction, respectively. The complete degradation of DZ was confirmed using its absorption peak in UV-vis spectra analysis over 60 min treatment. A wide variety of free radicals was identified during quenching tests. HO• and h+ played a pivotal role in the degradation process of DZ. Decreasing the degradation efficiency in the presence of anions was as Cl- > CO32- > NO3- > PO43- > SO42- > HCO3-. A negligible amount of leaching Fe (<0.2 mg/L) was found for ZnO@SiO2@Fe3O4, indicating that the catalyst possesses a high stability in oxidation systems. In addition, a significant potential was achieved in reusing of catalyst within five consecutive runs. In conclusion, ZnO@SiO2@Fe3O4/PMS/UV hybrid system can be utilized as a promising advanced oxidation process into efficient degradation of pesticides, thanks to easy recovery, high catalytic activity, co-production of different reactive species and high durability and recyclability potential.


Asunto(s)
Diazinón , Plaguicidas , Óxido de Zinc , Peróxidos , Dióxido de Silicio
8.
MethodsX ; 6: 1716-1727, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31384570

RESUMEN

Nitrate is one of the most important contaminants that can release into the environment predominantly as a result of anthropogenic processes. Excessive intake of nitrates may increase the risk of certain types of cancer. The aim of this study was to investigate the concentration of nitrate in drinking water and its health to people in Iran. This cross-sectional study has performed in 2019. Nitrate concentrations in drinking water supplies were obtained from peer-reviewed publications. Monte Carlo stimulations and mathematical models were used to determine the excess cancer risk. Risk level for assessing the carcinogen risk was 10-5 (1 per 100,000 persons). Nitrate concentrations and cancer risk related to nitrate were classified by GIS software. According to the obtained results, the drinking water supplies of Tehran, Mashhad (Khorasan Razavi), Zahedan (Sistan and Baluchestan), Shiraz (Fars), Qom, Ardabil and Ahwaz (Khuzestan) have higher nitrate concentrations than the limit recommended by WHO and Institute of Standards and industrial Research of Iran (ISIRI). The estimated cancer risks for the provinces of Tehran, Mashhad (Khorasan Razavi), Zahedan (Sistan and Baluchestan), Shiraz (Fars), Qom, Ardabil and Ahwaz (Khuzestan) were in the no negligible range set by the Health Canada and WHO. The majority of Iran provinces that have impermissible level of nitrate in drinking water supplies had a significant association between cancer prevalence and nitrate exposure. •The findings demonstrated that carcinogen risk values of nitrate exposure through drinking water was 0.001%.•Results showed that Tehran, Mashhad (Khorasan Razavi), Zahedan (Sistan and Baluchestan), Shiraz (Fars), Qom, Ardabil and Ahwaz (Khuzestan) are more exposed to additional cancer risk related to nitrosamine.•The results of this study is considered as the comprehensive report that indicate the association between gastrointestinal cancer and nitrate exposure through drinking water.

9.
MethodsX ; 6: 1101-1113, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31193382

RESUMEN

Response surface methodology (RSM) was applied to find the optimum parameters for COD and TOC removal from saline wastewaters using electrochemical oxidation process. The independent variables considered were reaction time, pH, salt concentration, and voltage. Optimization of parameters was performed by analysis of variance (ANOVA). Quadratic regression equation was suggested as a model for prediction of chemical oxygen demand (COD) and total organic carbon (TOC) removal efficiency. The results indicated that the COD and TOC removal efficiencies at the optimal conditions of pH 7.69, reaction time of 30.71 min, salt content of 30. 94 g/L and voltage of 7.41 V were 91.78% and 68.49%, respectively. In terms of COD and TOC removal efficiency, the coefficients of determination were found to be 0.95 and 0.94, respectively. This study suggests that electro-oxidation is an effective process in decreasing COD and TOC from saline wastewaters. Further, RSM was a suitable technique for optimization of the variables involved in COD and TOC removal through electro-oxidation process. •The findings demonstrate that response surface methodology is a good tool for the optimization of parameters of the experimental data.•A quadratic model was suggested as a good model for COD and TOC removal prediction.•The findings proved good agreement between the experimental data and the predicted equation.

10.
Chemosphere ; 232: 140-151, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31152898

RESUMEN

Catalytic oxidative degradation of acetaminophen (ACT) was evaluated using magnetic mesoporous carbon (MNPs@C) coupled with UV light and peroxymonosulfate (PMS). The performance of hybrid system (i.e., MNPs@C/UV/PMS) was assessed as a function of some operational factors (e.g., reaction time and different concentrations of catalyst, PMS and ACT) in a batch system. MNPs@C represented a high magnetic response and was easily recovered from aqueous solution via an external magnet. A significant synergistic effect was observed among the applied techniques in MNPs@C/UV/PMS system for ACT degradation. After 40 min reaction, the removal efficiencies of 97.4 and 63.5% were obtained for ACT and TOC, respectively. Both adsorption and oxidation mechanisms were responsible simultaneously for ACT removal in MNPs@C/UV/PMS system. Under optimum conditions, the removal rates of ACT and TOC were reduced slightly to 91.7 and 49.4% after five consecutive catalyst uses, which indicates the excellent reusing potential of MNPs@C. In addition, a high stability was detected for as-prepared catalyst during recycling tests, since the quantity of leached Fe was <0.2 mg/L. Methanol and tert-butyl alcohol showed a strong quenching effect on the performance of MNPs@C/UV/PMS system, demonstrating the dominant role of SO4•- and HO radicals in ACT degradation process. MNPs@C in comparison with ferrous ions, as a homogeneous catalyst, showed a better performance in the activation of PMS and ACT degradation. Integration of MNPs@C, UV and PMS exhibited an excellent performance into ACT removal over 40 min reaction, which can be utilized as an effective and promising technique for the efficient decontamination of polluted waters.


Asunto(s)
Acetaminofén/química , Peróxidos/química , Procesos Fotoquímicos , Carbono/química , Catálisis , Hierro , Magnetismo , Imanes , Oxidación-Reducción , Reciclaje
11.
Int J Biol Macromol ; 131: 633-645, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30857962

RESUMEN

Magnetic separation of toxic dyes has become a potential and effective method in wastewater treatments. In present research, a facile in situ one step co-precipitation synthetic approach is used to develop water-dispersible Fe3O4/Chitosan/Glutaraldehyde nanocomposites (MCS-GA) as an efficient adsorbent for the removal of Crystal Violet (CV) from aqueous solution. The physicochemical properties of the MCS-GA were investigated using FTIR, SEM, TEM, XRD, BET, and VSM techniques. 5-level and 3-factors central composite design (CCD) combined with the response surface methodology (RSM) was applied to investigate the statistical relationships between independent variables i.e. initial pH, adsorbent dosage, initial dye concentration and adsorption process as response. The optimal values of the parameters for the best efficiency (99.99%) were as follows: pH of 11, the initial dye concentration of 60 mg L-1 and MCS-GA dosage of 0.817 g L-1, respectively. The adsorption equilibrium and kinetic data were fitted with the Langmuir monolayer isotherm model (qmax: 105.467 mg g-1, R2: 0.996) and pseudo-second order kinetics (R2: 0.960). Thermodynamic parameters (R2 > 0.941, ΔH°: 690.609-896.006 kJ mol-1, ΔG°: -1.6849 to -13.4872 kJ mol-1, ΔS°: 0.168-0.232 kJ mol-1 K-1) also indicated CV adsorption is feasible, spontaneous and endothermic in nature. Overall, taking into account the excellent efficiency, good regeneration and acceptable performance in real terms, MCS-GA can be introduced as a promising absorbent for dyes removal from the textile wastewater.


Asunto(s)
Cationes/química , Quitosano/química , Colorantes/química , Glutaral/química , Nanopartículas de Magnetita/química , Adsorción , Violeta de Genciana , Concentración de Iones de Hidrógeno , Cinética , Proyectos de Investigación , Temperatura , Termodinámica , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
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