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171.
(‐)‐Epigallocatechin‐3‐gallate decreases colonic inflammation and permeability in a mouse model of colitis,but reduces macronutrient digestion and exacerbates weight loss
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172.
Our previous exciting results on graphene (G)-conducting polymer (polyaniline (PANI) and polyethylenedioxythiophene (PEDOT)) supercapacitors have prompted the investigation of G-substituted conducting polymer nanocomposites used as electrode materials in supercapacitors. The solubility of ortho-substituted PANI derivatives in a few common solvents has allowed the fabrication of stretchable films by the casting technique. The G-poly (o-anisidine) (G-POA) nanocomposites were synthesized with different weight ratios of G to o-anisidine by chemical methods, and characterized by various techniques, such as, scanning electron microscopy, transmission electron microscopy, UV–visible spectroscopy, Raman spectroscopy, thermogravimetric analysis and cyclic voltammetry. The electrical conductivity and specific capacitance obtained for the G-POA nanocomposites were found to be dependent on the weight ratios of G to o-anisidine. The specific capacitance and the charging–discharging behavior of the POA and G-POA supercapacitors were investigated in a 2 M H2SO4, 0.2 M LiClO4 and 1 M 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6) ionic liquid. The specific capacitance of 380 F g−1 was calculated for the 1:1 weight ratio of G to o-anisidine based G-POA supercapacitor in 2 M H2SO4. The presence of the electron-donating group (–OCH3) in the o-anisidine allows the electrons through the lone pair of nitrogen atoms to enhance the electronic charge transport inside the G-POA supercapacitor electrodes. However, the G-POA-based supercapacitors showed a 27% decrease in the specific capacitance in H2SO4 and 16% decrease in the ionic liquid (BMIM-PF6) after 1000 cycles of charging and discharging. The higher stability and rate capability of the G-POA based supercapacitor in an ionic liquid (BMIM-PF6) as compared to an aqueous electrolytic supercapacitor opens the door for the fabrication of stable supercapacitors for practical applications. 相似文献
173.
Thermal energy storage technologies and systems for concentrating solar power plants 总被引:1,自引:0,他引:1
Sarada Kuravi Jamie Trahan D. Yogi GoswamiMuhammad M. Rahman Elias K. Stefanakos 《Progress in Energy and Combustion Science》2013
This paper presents a review of thermal energy storage system design methodologies and the factors to be considered at different hierarchical levels for concentrating solar power (CSP) plants. Thermal energy storage forms a key component of a power plant for improvement of its dispatchability. Though there have been many reviews of storage media, there are not many that focus on storage system design along with its integration into the power plant. This paper discusses the thermal energy storage system designs presented in the literature along with thermal and exergy efficiency analyses of various thermal energy storage systems integrated into the power plant. Economic aspects of these systems and the relevant publications in literature are also summarized in this effort. 相似文献
174.
Nayereh Soltani Elias Saion Mohd Zobir Hussein Maryam Erfani Alam Abedini Ghazaleh Bahmanrokh Manizheh Navasery Parisa Vaziri 《International journal of molecular sciences》2012,13(10):12242-12258
ZnS and CdS nanoparticles were prepared by a simple microwave irradiation method under mild conditions. The obtained nanoparticles were characterized by XRD, TEM and EDX. The results indicated that high purity of nanosized ZnS and CdS was successfully obtained with cubic and hexagonal crystalline structures, respectively. The band gap energies of ZnS and CdS nanoparticles were estimated using UV-visible absorption spectra to be about 4.22 and 2.64 eV, respectively. Photocatalytic degradation of methylene blue was carried out using physical mixtures of ZnS and CdS nanoparticles under a 500-W halogen lamp of visible light irradiation. The residual concentration of methylene blue solution was monitored using UV-visible absorption spectrometry. From the study of the variation in composition of ZnS:CdS, a composition of 1:4 (by weight) was found to be very efficient for degradation of methylene blue. In this case the degradation efficiency of the photocatalyst nanoparticles after 6 h irradiation time was about 73% with a reaction rate of 3.61 × 10−3 min−1. Higher degradation efficiency and reaction rate were achieved by increasing the amount of photocatalyst and initial pH of the solution. 相似文献
175.
Physicochemical,crystallinity, pasting and thermal properties of heat‐moisture‐treated pinhão starch
Vnia Zanella Pinto Nathan Levien Vanier Bruna Klein Elessandra da Rosa Zavareze Moacir Cardoso Elias Luiz Carlos Gutkoski Elizabete Helbig Alvaro Renato Guerra Dias 《Starch - St?rke》2012,64(11):855-863
The effect of heat‐moisture treatment (HMT) on the properties of pinhão starches under different moisture and heat conditions was investigated. The starches were adjusted to 15, 20 and 25% moisture levels and heated to 100, 110 and 120°C for 1 h. The X‐ray diffractograms, swelling power, solubility, gel hardness, pasting properties and thermal properties of the native and HMT pinhão starches were evaluated. Compared to native starch, there was an increase in the X‐ray intensity and gel hardness of HMT starches, with the exception of the 25% moisture‐treated and 120°C heat‐treated starch. HMT reduced the swelling power and solubility of the pinhão starches when compared to native starch. There was an increase in the pasting temperature, final viscosity and setback and a decrease in the peak viscosity and breakdown of HMT pinhão starches compared to native starch. HMT increases the gelatinisation temperature of native pinhão starch and reduces gelatinisation enthalpy. 相似文献
176.
Elessandra da Rosa Zavareze Vânia Zanella PintoBruna Klein Shanise Lisie Mello El HalalMoacir Cardoso Elias Carlos Prentice-HernándezAlvaro Renato Guerra Dias 《Food chemistry》2012,132(1):344-350
This study investigated the effects of sodium hypochlorite oxidation and a heat-moisture treatment of potato starch on the physicochemical, pasting and textural properties of potato starches in addition to the water vapour permeability (WVP) and mechanical properties of potato starch films produced from these starches. The carbonyl contents, carboxyl contents, swelling power, solubility, pasting properties and gel texture of the native, oxidised and heat-moisture treated (HMT) starches were evaluated. The films made of native, oxidised and HMT starches were characterised by thickness, water solubility, colour, opacity, mechanical properties and WVP. The oxidised and HMT starches had lower viscosity and swelling power compared to the native starch. The films produced from oxidised potato starch had decreased solubility, elongation and WVP values in addition to increased tensile strength compared to the native starch films. The HMT starch increased the tensile strength and WVP of the starch films compared to the native starch. 相似文献
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João Renato de Jesus Junqueira Jefferson Luiz Gomes Corrêa Kamilla Soares de Mendonça Ronaldo Elias de Mello Júnior Amanda Umbelina de Souza 《Food and Bioprocess Technology》2018,11(10):1863-1875
Pulsed vacuum osmotic dehydration (PVOD) is a widely used technique for reducing moisture content and water activity in biological products. This study aimed to analyze the effect of vacuum application (VA) on PVOD of beetroot, carrot, and eggplant slices, with respect to chemical (moisture, water activity, specific pigments, polyphenols, and sodium content), optical (color), mechanical (shrinkage, maximum stress, and elasticity), and structural (microstructure) properties. PVOD was conducted at three different vacuum pressures (0, 40, and 80 kPa, for 10 min), during a total process time of 300 min. Osmotic processing was performed at 35 °C by using a ternary osmotic solution [40% sucrose +?10% sodium chloride (w/w)]. Eggplant and carrot samples were more sensitive to VA, compared to beetroot. This was related to their porous and less compact structure. In general, VA reduced the moisture content and water activity and preserved the carotenoid content. VA caused loss of betalain and phenolic acid, favored sodium uptake, and induced significant changes in the optical, mechanical, and structural properties, compared to the osmotic processing conducted at atmospheric pressure. 相似文献