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1.
Environ Sci Pollut Res Int ; 30(26): 69514-69532, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37138129

RESUMO

The present work focuses on the photocatalytic degradation of methylene blue (MB) on erbium ion (Er3+) doped TiO2 under visible light. Pure TiO2 nanoparticles and erbium (Er3+) doped TiO2 nanocomposite (Er3+/TiO2) NCs were synthesized using the sol-gel method. The synthesized (Er3+/TiO2) NCs were characterized using Fourier transform infrared spectroscopy (FTIR), high resolution scanning electron microscopy (HR-SEM), elementary dispersive X-ray (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectra (XPS), specific surface area (BET), zeta potential, and particle size. Different parameters were used to study their efficiency for the photoreactor (PR) and the synthesized catalyst. These parameters include pH of the feed solution, the rate of flow, the presence of an oxidizing agent (aeration pump), different ratios of nanoparticles, the amount of catalyst, and the concentrations of pollutants. An example of an organic contaminant was the dye methylene blue (MB). The result achieved using the synthesized nanoparticles (I) under ultraviolet light pure TiO2 was found to have degraded by 85%. For (Er3+/TiO2) NCs under visible light, dye removal increased with pH to a maximum of 77% degradation at pH 5. Furthermore, photocatalytic efficiency improves to 80% at 40 rpm (3 l/h) low motor speed. The degradation efficiency decreased to 70% when the MB concentration was increased from 5 to 30 mg/L. When oxygen content was increased using an air pump, and deterioration reached 85% under visible light, it improved performance.


Assuntos
Metais Terras Raras , Nanopartículas , Azul de Metileno/química , Érbio , Luz , Titânio/química , Nanopartículas/química , Catálise
2.
Environ Sci Pollut Res Int ; 29(43): 65699-65722, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35499738

RESUMO

Rapid urbanisation has had a significant negative influence on the water bodies that flow through and around urban areas. This study aims to evaluate the water quality and analyse the suitability for drinking and irrigation uses. This study envisaged assessing the water quality status of the groundwater using the pollution index of groundwater (PIG), ecological risk index (ERI) and multivariate statistical techniques, namely cluster analysis (CA) and principal component analysis (PCA), that were applied to differentiate the sources of water quality variation and determine the cause of pollution in the study area. Most groundwater is unsuitable for drinking and irrigation consumption, depending on analyses. PIG values indicated high pollution levels in the studied water body, rendering it unsuitable for any practical purpose. CA results showed the impact of surface water and treatment plant on groundwater. PCA was used to identify four important factors in the groundwater, including mineral and nutrient pollution, heavy metal pollution, organic pollution and faecal contamination. The deteriorating water quality of the groundwater was demonstrated to originate from vast sources of anthropogenic activities, especially municipal sewage discharge. Study wells had greater concentrations of Cl- and Na+ in their water because seawater flows into the aquifer system and mixes with the marine aquifer matrix. Thus, the current work reveals how to employ the PIG and multivariate statistical approaches to obtain more accessible and more meaningful information about the water quality of groundwater and to identify the sources of pollution.


Assuntos
Água Subterrânea , Metais Pesados , Poluentes Químicos da Água , Egito , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Metais Pesados/análise , Esgotos/análise , Poluentes Químicos da Água/análise , Qualidade da Água
3.
Appl Immunohistochem Mol Morphol ; 24(2): 75-87, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25710583

RESUMO

Hepatocellular carcinoma (HCC) constitutes 70.48% of all liver tumors among Egyptians with multifactorial etiology and complex pathogenesis. HCV infection is the most common risk factor of HCC in Egypt, which commonly develops on top of cirrhosis (HCC-C); however, 15% to 20% of HCC are reported to arise in noncirrhotic livers (HCC-NC). This study aimed to explore the differences in the immunohistochemical expression of p53, c-Jun, c-Myc, and p21 between HCC-C and HCC-NC to verify the underlying molecular pathways and to study their role in hepatocarcinogenesis. This study investigated 103 cases of HCC (86 cases of HCC-C and 17 cases HCC-NC including tumorous and nontumorous tissues) together with 10 cases of chronic hepatitis and 10 cases of pure cirrhosis as control groups. Zero, 100%, 100%, and 50% of chronic hepatitis cases were positive for p53, c-Jun, c-Myc, and p21, respectively. All cirrhotic cases were negative for p53 and c-Jun, whereas they were all positive for c-Myc and p21. A total of 41%, 11.65%, 86.4%, and 57.3% of HCC cases showed p53, c-Jun, c-Myc, and p21 expression, respectively. The only difference between HCC-C and HCC-NC was the H-score values of p21 expression, which were higher in HCC-C compared with HCC-NC (P=0.03). HCV-related HCC commonly develops on top of cirrhosis with a minority develops on top of noncirrhotic liver. Only p21 pathway appears to be upregulated in favor of HCC-C than HCC-NC. p53 is considered as a late-event molecular carcinogen, whereas p21 and c-Myc may serve as early-event molecular carcinogen in HCC. The oncogenic role of p21 may be related to its cytoplasmic localization and its promotion of c-Myc expression. Progressive increase in the intensity of c-Myc expression from chronic hepatitis to cirrhosis to HCC may refer to its role as a multistep regulator of hepatocarcinogenesis. The marked reduction of c-Jun in HCC may refer to its tumor suppressor activity.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Fibrose/diagnóstico , Hepacivirus/fisiologia , Hepatite C/diagnóstico , Neoplasias Hepáticas/diagnóstico , Adulto , Carcinogênese , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Diagnóstico Diferencial , Egito , Feminino , Fibrose/complicações , Fibrose/patologia , Regulação Neoplásica da Expressão Gênica , Hepatite C/complicações , Hepatite C/patologia , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
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