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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124556, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850820

RESUMO

For the sustainable advancement of industrial expansion that is environmentally conscious, harmful dyes must be removed from wastewater. Untreated effluents containing colors have the potential to harm the ecosystem and pose major health risks to people, animals, and aquatic life. Here, we have fabricated Ni or Fe modified with BaTiO3 materials and effectively utilized them for Reactive Red 120 (RR 120) dye degradation under UV-A light. The synthesized materials were characterized, and their structural, and photo-physical properties were reported. Phase segregation was not present in the XRD pattern, as evidenced by the absence of secondary phase peaks linked to iron, nickel, or oxides. Low metal ion concentrations may be the cause of this, and the presence of those elements was confirmed by XPS measurements. The Raman spectra of the BaTiO3/Ni and BaTiO3/Fe samples show a widened peak at 500 cm-1, which suggests that Ni or Fe are efficiently loaded onto the BaTiO3. RR 120 dye photodegradation under UV light conditions was effectively catalyzed by BaTiO3/Fe, as evidenced by its superior performance in the UV irradiation technique over both BaTiO3 and BaTiO3/Ni. Compared to bare BaTiO3, both metal-modified materials efficiently degraded the RR 120 dye. Acidic pH facilitated the degradation process, which makes sense given that the heterogeneous photo-Fenton reaction was the mechanism of degradation along with BaTiO3 sensitization. High-acidity sewage can be dangerous and carcinogenic, and conventional biological treatment methods are not appropriate for managing it. In the current investigation, it may be used to treat color effluents with extremely low pH levels. Additionally, the ability of the produced nanocomposites to inhibit the growth of twenty pathogens was examined, along with two fungi, fifteen Gram-negative Bacilli (GNB), one Gram-positive Bacilli (GPB), and two Gram-positive Cocci (GBC).


Assuntos
Compostos de Bário , Ferro , Níquel , Fotólise , Titânio , Raios Ultravioleta , Titânio/química , Titânio/farmacologia , Ferro/química , Níquel/química , Compostos de Bário/química , Rodaminas/química , Corantes/química , Análise Espectral Raman , Poluentes Químicos da Água/química , Triazinas
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123972, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38306923

RESUMO

In recent years, researchers have been actively investigating metal oxide-based materials with narrow bandgaps due to their potential applications toward wastewater treatment and oxygen evolution reactions (OER). In this study, we successfully synthesized g-C3N4 (GCN), Fe2O3, and Fe2O3/g-C3N4 (FGCN) using thermal polymerization and hydrothermal methods. We characterized the physicochemical and structural properties of these materials through various analytical techniques including XRD, FT-IR, UV-DRS, XPS, FE-SEM, and HR-TEM analyses, confirming the effective construction of the FGCN composite catalyst. We evaluated the photocatalytic activity of Fe2O3, GCN, and FGCN composite catalysts by assessing their ability to degrade rhodamine B (RhB) and crystal violet (CV) by exposing them to sunlight for 150 min. Among these catalysts, the FGCN composite demonstrated excellent photocatalytic performance, achieving 93 % and 95 % degradation of RhB and CV, respectively, under 150 min of sunlight exposure. The developed Fe2O3/g-C3N4@Nickel foam (FGCN@NF) composite catalyst exhibits remarkable OER performance, with a reduced Tafel slope of 64 mV/dec and a low overpotential of 290 mV at a current density of 10 mA/cm2 and shows excellent durable performance over a long time (15 h). Total Organic Carbon (TOC) analysis confirmed the mineralization of both dyes. The photocatalytic performance remained largely unchanged after five consecutive experiments, demonstrating excellent reusability and photostability. Trapping experiments revealed that O2●- is the main species responsible for the photocatalytic decomposition of various dyes by the FGCN composite catalyst. Therefore, the development of a versatile photo/electrocatalytic system that can efficiently promote energy conversion in environmental applications has attracted great attention.

3.
Environ Res ; 209: 112819, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35085559

RESUMO

In this work, the Ag modified ZnS nanoparticles were synthesized via the hydrothermal method, and used for photocatalytic degradation of organic dyes. Various analytical techniques were utilized to characterize the prepared ZnS and Ag incorporated ZnS nanoparticles. The vibrational and structural properties of the prepared nanoparticles were analyzed by FT-IR and XRD, which confirm the modification of Ag in the ZnS. The broadening of the hydroxyl group after incorporation of Ag in ZnS was observed in the FT-IR spectra. The additional (111), (200), and (220) planes in XRD of Ag-ZnS belong to the silver. The increased absorbance in the entire visible region facilitates the ZnS/Ag photocatalytic performance under direct sunlight. ZnS/Ag nanoparticles showed excellent photocatalytic activity toward degradation of RR 120, DB 15, and AB 1. The ZnS/Ag catalyst efficiently degrades the RR 120 under sunlight with higher pseudo-first order kinetic k = 0.0179 min-1 than the other dyes. The reusability study exhibited ZnS/Ag has highly stable and degraded more than 80% of RR 120 under sunlight irradiation after 4th cycle.


Assuntos
Nanopartículas Metálicas , Prata , Catálise , Luz , Nanopartículas Metálicas/química , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfetos , Compostos de Zinco
4.
Environ Res ; 197: 111115, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33812877

RESUMO

The current work reports the photocatalytic and antibacterial performance of tin (Sn) doped zinc oxide (ZnO) nanoparticles synthesized via ultrasonic aided co-precipitation technique. The increase of Sn concentration decreased the lattice parameter and increased the crystallite size without changing the ZnO structure. The hexagonal shaped particles and sheets obtained for 3% and 5% Sn substituted ZnO, respectively. The increase of dopant concentration reduced the reflectance and optical band gap energy of Sn doped ZnO. The vibrational band present at 1443 cm-1 confirmed the successful bond formation of Sn-O-Zn. The 5% Sn doped ZnO nanoparticles exhibited greater dye elimination rate of methylene blue compared to 3% Sn. The antibacterial activity of Sn doped ZnO showed the higher zone of inhibition about 14 mm against different pathogens. The 5% Sn doped ZnO photocatalyst improve the transfer rate of photo excite carrier and decrease the rate of recombination which greatly influence on the photocatalytic and antibacterial performance.


Assuntos
Nanopartículas , Óxido de Zinco , Antibacterianos/farmacologia , Azul de Metileno
5.
Indian J Clin Biochem ; 35(4): 488-496, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33013020

RESUMO

The study was undertaken to evaluate the therapeutic effect of mustard oil incorporated diet in streptozotocin (STZ)-induced type 1 diabetic rats. Dietary composition has shown to play a significant role in improving insulin sensitivity. Various authors have reported the hypoglycemic effect of mustard oil in experimentally induced diabetic rats. In the present study, reverse transcriptase polymerase chain reaction (RT-PCR) was done to analyze the Glut 4 expression in STZ induced diabetic rats as it is a key player in glucose homeostasis. The effect of mustard oil on serum biochemical parameter and insulin levels was also studied. Twenty-four male Wistar rats were randomly divided into three different groups with each containing eight animals. The first, second and third groups were control, diabetic control and treatment group with mustard oil respectively. All the rats in respective groups were fed for 60 days with iso-caloric mash diet containing 8% lipid. Diabetes was induced by intra-peritoneal administration of STZ (40 mg/kg body weight). A highly significant reduction in blood glucose level, with an increase in insulin activity was observed in mustard oil-treated diabetic rats when compared to control group indicating anti-hyperglycemic activity of mustard oil. Mustard oil-treated diabetic rats showed increased expression of  Glut 4 in muscle tissue when compared to diabetic control. A significant reduction in the levels of triacylglycerols, total cholesterol, VLDL and LDL and raised plasma HDL were noticed in mustard oil-treated diabetic rats when compared to diabetic control rats. Histopathological studies revealed a mild regeneration of ß cells of pancreas in mustard oil-treated diabetic rats. The results from our investigation suggest that mustard oil elicits hypoglycemic effect by increased insulin activity and up-regulation of  Glut 4 gene expression in muscle tissue of STZ-induced diabetic rats.

6.
Biophys J ; 119(8): 1481-1488, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33031739

RESUMO

Biological cells deform on a nanometer scale when their transmembrane voltage changes, an effect that has been visualized during the action potential using quantitative phase imaging. Similar changes in the optical path length have been observed in photoreceptor outer segments after a flash stimulus via phase-resolved optical coherence tomography. These optoretinograms reveal a fast, millisecond-scale contraction of the outer segments by tens of nanometers, followed by a slow (hundreds of milliseconds) elongation reaching hundreds of nanometers. Ultrafast measurements of the contractile response using line-field phase-resolved optical coherence tomography show a logarithmic increase in amplitude and a decreasing time to peak with increasing stimulus intensity. We present a model that relates the early receptor potential to these deformations based on the voltage-dependent membrane tension-the mechanism observed earlier in neurons and other electrogenic cells. The early receptor potential is caused by conformational changes in opsins after photoisomerization, resulting in the fractional shift of the charge across the disk membrane. Lateral repulsion of the ions on both sides of the membrane affects its surface tension and leads to its lateral expansion. Because the volume of the disks does not change on a millisecond timescale, their lateral expansion leads to an axial contraction of the outer segment. With increasing stimulus intensity and the resulting tension, the area expansion coefficient of the disk membrane also increases as thermally induced fluctuations are pulled flat, resisting further expansion. This leads to the logarithmic saturation observed in measurements as well as the peak shift in time. This imaging technique therefore relates the structural changes in the photoreceptor to the underlying neurological function of transducing light into electrical signals. Such label-free optical monitoring of neural activity using fast interferometry may be applicable not only to optoretinography but also to neuroscience in general.


Assuntos
Neurônios , Células Fotorreceptoras , Potenciais de Ação , Interferometria , Íons
7.
BMC Complement Altern Med ; 16: 55, 2016 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-26852336

RESUMO

BACKGROUND: Emu oil is a product of animal origin used for the treatment of inflammation, burns etc. as a part of aboriginal medicine in Australia. Crohn's disease is a common inflammatory manifestation in humans and other animal species relating to the ulceration and digestive disturbances in upper gastro-intestinal tract. Aloe vera is commonly used substance from plant sources for inflammation, wound healing and various other properties. Given the difference in the source of the substances all the while playing a similar therapeutic role in different parts of the world, the present investigation was undertaken to evaluate the protective effect of aloe vera and emu oil alone and in combination; in comparison to sulfasalazine (Allopathic drug) as an alternative for the treatment of Crohn's disease. METHODS: Wistar albino rats were divided into six groups with two sub-groups of six animals each. After pre-treating the animals with sulfasalazine, aloe vera, emu oil and their combination for five consecutive days, the animals were sub-cutaneously administered indomethacin on 4(th) and 5(th) day and each sub-group was sacrificed on day 6 and 9. After sacrifice, serum and intestine of these animals was collected. Intestine length from duodenum till caecum was measured for estimating relative organ weight and disease activity index. Part of intestine was preserved in formalin for histopathology while the rest was used for analysis of oxidative parameters and myeloperoxidase. Serum collected was used for measuring alkaline phosphatase and cholesterol. RESULTS: Assessment of the parameters in treatment groups indicated that the combination of aloe vera and emu oil resulted in better protection by suppressing the oxidative (P < 0.05) and histomorphological changes indicating a enhanced effect of these two agents which was found to be better than sulfasalazine. CONCLUSION: The combination of emu oil and aloe vera exhibited enhanced effect resulting in significant protection from indomethacin induced ulceration. This might be due to the different mechanism of anti-inflammatory effects (Salicylic acid in aloe vera and n3, n6 fatty acids acting as pseudosubstrates to cyclooxygenase enzyme) of components of the animal and plant products tested.


Assuntos
Aloe , Doença de Crohn/prevenção & controle , Óleos/uso terapêutico , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/uso terapêutico , Animais , Antioxidantes/metabolismo , Ceco/efeitos dos fármacos , Ceco/patologia , Doença de Crohn/induzido quimicamente , Doença de Crohn/patologia , Modelos Animais de Doenças , Feminino , Íleo/efeitos dos fármacos , Íleo/patologia , Indometacina , Ratos , Ratos Wistar
8.
Gastroenterology ; 102(6): 1846-53, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1587404

RESUMO

To determine the effect of mucosal sodium and mucosal ouabain on active Rb+(K+) absorption, unidirectional and net 86Rb+ fluxes were measured under voltage-clamp conditions in the distal colon of normal and sodium-depleted rats. The role of mucosal sodium (independent of serosal sodium) was evaluated in a model of Rb+(K+) absorption in which serosal ouabain markedly enhanced active Rb+(K+) absorption. In normal rats, mucosal sodium was a competitive inhibitor of Rb+(K+) absorption, and Rb+(K+) absorption consisted of a mucosal sodium-sensitive component and a mucosal sodium-insensitive component. Further, mucosal ouabain almost completely inhibited the mucosal sodium-insensitive component but did not affect the mucosal sodium-sensitive component. In sodium-depleted rats, both mucosal sodium-sensitive and mucosal sodium-insensitive fractions of Rb+(K+) absorption were also identified. Aldosterone markedly stimulated the mucosal sodium-sensitive component (1.68 +/- 0.15 vs. 0.60 +/- 0.10 muEq.h-1.cm-2) but not the sodium-insensitive component (0.88 +/- 0.09 vs. 0.64 +/- 0.06 muEq.h-1.cm-2) component of Rb+(K+) absorption; however, in contrast to normal animals, mucosal sodium in sodium-depleted animals was a noncompetitive inhibitor of Rb+(K+) absorption. The mucosal sodium-insensitive component of Rb+(K+) absorption in sodium-depleted animals was substantially inhibited by mucosal ouabain, but the mucosal sodium-sensitive component, unlike that in normal animals, was partially inhibited by mucosal ouabain. These studies indicate that the characteristics of the Rb+(K+) absorptive process in sodium-depleted animals differ significantly from those present in normal animals, suggesting that aldosterone induces an Rb+(K+) absorptive mechanism not present in normal animals.


Assuntos
Colo/metabolismo , Absorção Intestinal/efeitos dos fármacos , Ouabaína/farmacologia , Potássio/metabolismo , Sódio/farmacologia , Animais , Técnicas In Vitro , Mucosa Intestinal/metabolismo , Masculino , Ratos , Ratos Endogâmicos , Radioisótopos de Rubídio/metabolismo , Sódio/metabolismo
9.
Indian J Exp Biol ; 28(3): 295-6, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2163978

RESUMO

The effect of penicillic acid on isolated frog's heart has been studied along with ions of Na+,K+ and Ca2+. Penicillic acid has been found to inhibit the entry of these ions into cardiac tissue thereby arresting the action of the heart. The blockage can be washed away by perfusion with Ringer's solution.


Assuntos
Canais de Cálcio/efeitos dos fármacos , Caproatos/toxicidade , Coração/efeitos dos fármacos , Ácido Penicílico/toxicidade , Canais de Potássio/efeitos dos fármacos , Canais de Sódio/efeitos dos fármacos , Animais , Ranidae
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