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•For the first time, we have synthesized graphene nanosheets in the presence of pomegranate juice.•Here pomegranate juice was used not only as reductant but also as capping ...agent.•FT-IR, XRD, SEM, EDS and TEM were used to characterize the samples.•According to TEM image, graphene nanosheet is individually exfoliated after stirring for 24h.•As shown in the TEM image, graphene monolayer is obtained.
For the first time, we have successfully synthesized graphene nanosheets in the presence of pomegranate juice. In this approach, pomegranate juice was used not only as reductant but also as capping agent to form graphene nanosheets. At first, the improved Hummer method to oxidize graphite for the synthesis of graphene oxide (GO) was applied, and then the as-produced graphene oxide was reduced by pomegranate juice to form graphene nanosheets. Fourier transformed infrared (FT-IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), high resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM) and raman were used to characterize the samples. The results obtained from the characterization techniques proved high purity of the final products.
In this work, Ag2CrO4 and Ag2Cr2O7 nanostructures have been sonochemically prepared using silver salicylate. The effect of preparation parameters on the morphology of the products was investigated by ...SEM images. Display omitted
► Herein, Ag2CrO4 and Ag2Cr2O7 nanostructures have been sonochemically prepared. ► The effect of preparation parameters on the morphology of the products was investigated. ► The photocatalytic activity of the as-prepared Ag2CrO4 nanoparticles was tested. ► XPS spectra indicated the high purity of Ag2Cr2O7 nanostructures obtained.
In this work, Ag2CrO4 and Ag2Cr2O7 nanostructures have been produced via a sonochemical method using silver salicylate as precursor. Besides silver salicylate, Na2CrO4 and (NH4)2Cr2O7 as starting reagents were applied. To investigate the effect of preparation parameters on the morphology and particle size of Ag2CrO4 and Ag2Cr2O7, sonication time, type of surfactant and its concentration were changed. The as-produced nanostructures were characterized by techniques like powder X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The scanning electron micrographs showed that particle-like and rod-like nanostructures of Ag2CrO4 and Ag2Cr2O7 were produced using different surfactants. To investigate the catalytic properties of Ag2CrO4 nanoparticles, photooxidation of methyl orange (MO) was performed. According to the obtained results, it was found that the methyl orange degradation was about 87.3% after 280min irradiation of visible light.
The degradation of methyl orange (MO) and neutral red (NR) was studied by the direct electrooxidation using nitrogen and sulfur co-doped graphene (NSG) supported antimony doped tin oxide (SnO2-Sb). ...Sol-gel and microwave technics were used to prepare the material (Ti/SnO2-Sb-NSG). Raman, XRD, FTIR and TGA/DSC analyses help to confirm the coating of titanium substrate with the SnO2-Sb-NSG film. Linear sweet voltammetry results show that Ti/SnO2-Sb-NSG material possesses high oxygen overvoltage. Three independent variables including electrolysis time, current density and dye concentration on the performance of the anodic oxidation system was modeled using the Box-Behnken Design. The optimum conditions for MO and NR degradation were for current density 18 mA/cm² and 58 mA/cm², electrolysis time 6 h and 6 h and dye concentration 29 mg/L and 82 mg/L, respectively. However, based on these optimums, MO was degraded at 98.71 % while NR was just degraded at 82.7%. Based on the intermediate compounds, the degradation mechanism of MO at the Ti/SnO2-Sb-NSG anode was proposed. Ti/SnO2-Sb-NSG electrode showed a higher efficient electrocatalytic performance for NR and MO degradation than that of Ti/Sb-SnO2 or Ti/Sb-SnO2-NG electrodes. Furthermore, the lifetime of Ti/SnO2-Sb-NSG was about 31.6 h while Ti/SnO2-Sb electrode was 9.0 h.
Podocytes constitute the outer layer of the renal glomerular filtration barrier. Their energy requirements strongly depend on efficient oxidative respiration, which is tightly connected with ...mitochondrial dynamics. We hypothesized that hyperglycemia modulates energy metabolism in glomeruli and podocytes and contributes to the development of diabetic kidney disease. We found that oxygen consumption rates were severely reduced in glomeruli from diabetic rats and in human podocytes that were cultured in high glucose concentration (30 mM; HG). In these models, all of the mitochondrial respiratory parameters, including basal and maximal respiration, ATP production, and spare respiratory capacity, were significantly decreased. Podocytes that were treated with HG showed a fragmented mitochondrial network, together with a decrease in expression of the mitochondrial fusion markers MFN1, MFN2, and OPA1, and an increase in the activity of the fission marker DRP1. We showed that markers of mitochondrial biogenesis, such as PGC-1α and TFAM, decreased in HG-treated podocytes. Moreover, PINK1/parkin-dependent mitophagy was inhibited in these cells. These results provide evidence that hyperglycemia impairs mitochondrial dynamics and turnover, which may underlie the remarkable deterioration of mitochondrial respiration parameters in glomeruli and podocytes.
•Impairment of mitochondrial dynamics underlies the pathogenesis of type 2 diabetes.•Mitochondrial respiration is altered in glomeruli isolated from diabetic STZ-rats.•High glucose induces mitochondrial fission and fragmentation in human podocytes.•Mitochondrial fusion, biogenesis and mitophagy are reduced in HG-treated podocytes.•HG can injure the kidney by alteration of podocytes and glomerular bioenergetics.
Quantitative structure activity relationship studies were applied on a series of 22 molecules of thiazolidine-2,4-dione, The compounds used are potent inhibitors of the 15-hydroxyprostaglandin ...dehydrogenase (15-PGDH). The present study was performed using multiple regression analysis (MLR) and artificial neural network (ANN)to predict a QSAR model using molecular descriptors. Our results suggest QSAR model based of the following descriptors: polarizability (Pol), molar volume (MV), hydration energy (HE), Surface area grid (SAG), molar weight (MW), Energy of frontier orbital’s EHOMO (The Highest Occupied Molecular Orbital) and ELUMO (The Lowest Unoccupied Molecular Orbital) and atomic net charges (qN3, qC4, qC5 and qO7) for the inhibitory activities of 15-hydroxyprostaglandin dehydrogenase. The best predictive models by MLR and ANN methods gave highly significant square correlation coefficient (R2) values of 0.9623 and 0.9963 respectively. The model also exhibited good predictive power confirmed by the high value of R2pred (0.7839and 0.6324 respectively).
Reactions between later metal salts and conjugational N-hetrocyclic sulfonate/ carboxylic acid under the presence of bipyridyl auxiliary ligands afforded a series of manganese, nickel, zinc, silver, ...cadmium coordination polymers bearing with phenyl pendant arm attached to quinoline skeletons, and they have been characterized by elements analysis, thermogravimetry, infrared spectroscopy and single-crystal X-ray diffraction studying. The series of polymers show interesting structural diversity in coordination environment, dimensions and topologies. They are all built from 2-D networks constructed from metal cluster through sulfonate or carboxylate groups, as the secondary building unit (SBU). The thermalgravimetric analyses show that they display framework stabilities in solid state. Variable-temperature magnetic susceptibility studies reveal the existence of antiferromagnetic interactions between adjacent Mn (II) ions in 1, and ferromagnetic interactions between Ni(II) ions for 2, respectively. The photo-luminescence properties of 3-5 have also been investigated systemically.
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•A series of coordination polymers based on later transition metal ions have been obtained.•They contain conjugational N-hetrocyclic sulfonate-carboxylic acid and bipyridyl auxiliary ligands.•They have been characterized systemically.•They exhibit structure diversity and interesting properties.
Due to the ions in its structure, that have a variety of important roles in bone metabolism, forsterite (FS, Mg.sub.2SiO.sub.4) is a promising candidate for orthopedic and dental applications. This ...paper studies forsterite synthesized through two methods, namely sol-gel (FSsg) and precipitation (FSpp), based on a thermodynamic approach. Therefore, the precursor gel and precipitate were analyzed through thermal gravimetric (TG), differential thermal gravimetric (DTG) and differential scanning calorimetric (DSC) analysis. The FSsg and FSpp powders were characterized by X-ray powder diffraction (XRD) and atomic force microscopy (AFM). XRD reveals that the synthesized forsterite is of high crystallinity. As is evidenced by AFM, the average size of the nanoparticles is around 40 nm for FSsg and 30 nm for FSpp. The potential reaction mechanisms for the two synthesis routes were also established. Keywords: forsterite, sol-gel, precipitation method, synthesis mechanisms, thermodynamic approach
Two new complexes of Zn(II) and Cd(II) with acetate and nicotinamide as mixed ligands were synthesized and characterized. The Zn(II) complex is mononuclear, Zn(ac)2(NA)2 (1), while the Cd(II) is a ...dinuclear one, Cd2(ac)4(NA)4.2H2O (2), where ac = acetate and NA = nicotinamide. The compounds were characterized by means of single-crystal X-ray diffraction, FTIR, 1H NMR, 13C NMR spectroscopy, thermal analysis and elemental analysis. The geometry of the metal ion is distorted tetrahedral for Zn(II) and distorted pentagonal bipyramid geometry for Cd(II). In the dinuclear complex, each metal ion is coordinated by three acetate groups, but there are two different types of coordination modes for the acetate ligands: bidentate chelating and bridging bidentate chelating.
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•Films of two glassy chalcogenide systems of Gex-Sb/As40-x-S50-Te10 were studied.•Optical constants as function of films composition are obtained in 0.25–30 μm range.•The transparent ...zone of the films is in the (0.6–2.5) μm spectral range.•The vibrational modes were determined from IR-SE, FTIR and Raman.•The stability of the films after QT was proved by AFM, SEM and SE analyses.
Thin films from two glassy systems of GexSb40-xS50Te10 and GexAs40-xS50Te10, with compositions x = 10, 20 and 27 at. %, were deposited on optical glass substrates by vacuum thermal evaporation of powdered parent chalcogenide glasses. The complex refractive index and dielectric constants of the films are determined by ellipsometry in a wide spectral range of 0.25–30 μm. In the transparent spectral region of 0.6–2.5 μm the refractive index values are within 2.9–2.3 and 3.3–2.4 for the As-contained and Sb-contained films, respectively. From the IR and Raman data analysis the basic chemical and oxygen-related impurity bonds are identified. The films durability properties were established by applying the US Military Standard quality tests. The quality-test-induced-changes in surface morphology were evaluated. The films are relatively stable after quality test treatments, which cause a small degree of densification and surface roughening for Sb-containing films and surface flattening for As-containing ones.
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