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31.
The essential oil and methanol extract of Satureja hortensis were tested for antifungal activity against Aspergillus flavus in vitro on Petri plates and liquid culture, and under storage conditions. The oil showed strong antifungal activity based on the inhibition zone and minimal inhibitory concentration values against the pathogen on Petri plates assays. The very low concentrations of them also reduced wet and dry mycelium weight of pathogen fungus in liquid culture. When the oils at 25, 12.5 and 6.25 microl/mL concentrations were applied to lemon fruits before seven days of pathogen inoculation on storage conditions, the decay on fruits caused by the pathogen could be prevented completely. The results in this study showed that the essential oil of S. hortensis had strong antifungal activity against pathogen fungi tested. So, the essential oil of S. hortensis could be used for management of this pathogen as a potential source of sustainable eco-friendly botanical fungicides.  相似文献   
32.
In this study, grape pomace (mixture of grape seeds and skins) powder (GPP), obtained from grape processing, was used at different concentrations [10.0 (GPP10), 20.0 (GPP10) and 30.0 (GPP10) g/100 g] in white chocolate formulation for the partial replacement of sucrose. The results indicated that GPP addition at a higher concentration (>10.0 g/100 g) significantly affected the particle size, moisture content, texture and flow behaviour of white chocolate samples (P < 0.05). However, using GPP at a concentration of 10.0 g/100 g had advantages for physicochemical and flow properties. As expected, under simulated in vitro digestion conditions, the bioaccessibility of total phenolic compounds in saliva, gastric juice and intestinal juice for GPP10 samples was significantly higher than the control (P < 0.05). In conclusion, results of the study showed that it was possible to partially replace the sucrose with GPP at a concentration of 10.0 g/100 g in white chocolate formulations.  相似文献   
33.
In this study, grape pomace (GP), a by-product consisting of grape skins and seeds rich in dietary fibres and polyphenols, was used in wafer sheets at different concentrations [5.00 (GP5), 10.0 (GP10), and 15.0 g 100 g−1 (GP15)] for the partial replacement of wheat flour (WF) and improve the functionality of wafer sheets. The GP inclusion at concentrations higher than 5.00 g 100 g−1 significantly affected the texture of sheets as well as the flow behaviour of batters, resulting in softer sheets and more viscous batters (P < 0.05). Moisture contents did not significantly change after GP addition (P > 0.05). After the addition of GP, the L* values decreased and the a* values increased, making the wafers darker (P < 0.05). Moreover, under simulated in vitro digestion conditions, the bioaccessibility of total phenolic compounds in saliva, gastric juice, and intestinal juice was significantly higher than control even at the lowest GP concentration (P < 0.05). Regarding sensory properties, only smoothness and crispness were significantly affected by GP addition, and samples were found to be crisper with higher concentrations of GP. In conclusion, it is possible to partially replace the WF in wafers with GP at a concentration of 5.00 g 100 g−1 to develop a product with higher functionality and nutrient content.  相似文献   
34.
This study is to perform the comprehensive investigation of PVC based ionic plasticized membrane (IPM) production by using room temperature ionic liquid (RTIL)‐based additives and the membrane application of selective Cr(VI) removal. Some significant parameters related to membrane structures that are membrane thickness, plasticizer rate, and type, RTILs rate, and type, the average molecular weight of PVC were studied to define the excellent polymeric membrane film composition. After that, the PVC based polymeric film used in the Cr(VI) transport and initial mass transfer coefficient (Jo) were about 3.57 × 10?7 mol s?1 m?2 by decyl substituted RTIL as an additive. Also, optimized membrane transport process has been considered as selective enough for Cr(VI) in the presence of the other heavy metal ions. Surface characterizations of the membranes have been performed to clarify the structural and the morphological assessment of IPMs at initial and end of Cr(VI) transport by SEM‐EDX, AFM, contact angle measurement and found a good relationship between the molecular structure of RTIL additive and membrane morphology. As we know that lots of researchers are still trying to find environmentally friendly, inexpensive and straightforward processes to remove toxic substances from industrial effluents or natural sources. At that point, our results can open a gate for cheap, novel and environmentally friendly Cr(VI) removal by PVC based membrane. J. VINYL ADDIT. TECHNOL., 25:E107–E119, 2019. © 2018 Society of Plastics Engineers  相似文献   
35.
Journal of Mechanical Science and Technology - The energy demand of world is increasing worldwide because of increasing population and developing technology. The use of environmentally friendly...  相似文献   
36.
This paper describes a simple and fast process for the fabrication of flexible and textile‐based supercapacitors. Symmetric electrodes made up of binder‐free ternary composites of manganese oxide (MnO2) nanoparticles, single walled carbon nanotubes (SWNT) and a conducting polymer (either polyaniline (PANI) or poly(3,4‐ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT:PSS)) were layer‐by‐layer deposited onto cotton substrates by dip coating method. Solid‐state supercapacitor devices were assembled using a gel electrolyte. Specific capacitances of 294 F/g and 246 F/g were obtained for MnO2/SWNT/PANI and MnO2/SWNT/PEDOT:PSS ternary nanocomposite supercapacitors, respectively. Power densities for these supercapacitors were 746.5 W/kg and 640.5 W/kg for MnO2/SWNT/PANI and MnO2/SWNT/PEDOT:PSS, respectively. Good capacity retention (more than 70%) upon cycling over 1000 times was achieved for both electrode compositions. Supercapacitors demonstrated in this work would be well suited as disposable power sources for wearable and intelligent textiles. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
37.
Clean Technologies and Environmental Policy - The United Nations 2030 agenda states various sustainable development goals (SDGs) to counter climate change affecting individuals' health and...  相似文献   
38.
A theoretical methodology was developed to find total equivalent temperature difference (TETD) values for multilayer flat roofs and walls of buildings. The TETD values based on time lag and decrement factor are estimated using measured hourly solar radiation on a horizontal surface and outside air temperatures. The time lag and decrement factor are obtained numerically using periodic solution of one-dimensional transient heat transfer problem for the building structures. The problem is initially formulated using a differential equation and the appropriate initial and boundary conditions. It is then converted into dimensionless form and solved by application of complex finite Fourier transform (CFFT). The solution is used to find hourly variation of temperature inside the structure, the heat gain to the building through the structure, the highest and lowest temperatures at the inner and outer surfaces of the roofs and walls, and the time periods involved in reaching these temperatures. Sol-air temperatures for different directions as well as time lag and decrement factor are obtained, and these are used to determine the TETD values of the structures.  相似文献   
39.
Corrosion fatigue (CF) behavior of AISI 316L was investigated in a 3 pct NaCl aqueous solution at an R = ? 1 stress ratio and a frequency of 60?Hz at room temperature. The test scale specimen was 7 cm2. The passive (0 mVRef), pitting (120?mVRef), and cathodic (? 1400?mVRef) polarization potentials were statically applied and recorded during CF tests until the samples were broken. The shaft material surface was treated with a ball burnishing (BB) process. By the results, the fatigue behavior of AISI 316L was affected by polarization potential and surface treatment. Under 0?mV potential charged tests for 5?×?105 cycles, BB treatment raised the CF strength of the shaft material from about 448 to 702?MPa with a percent 57 increase. Fractographic observations revealed that corrosion pits occurred during the experiments where anodic potential was applied and that transgranular surface fractures occurred in all cases.  相似文献   
40.
Nano-silica particles were deposited on acid-etched hydrophilic aluminum (Al) substrates by immersion in well-dispersed nano-silica aqueous suspension and tetramethylamonium hydroxide, followed by a heat treatment. The surface was then further treated by a reaction with fluorosilane. The hydrophobicity, surface morphology, and mechanical properties of the coated Al substrates were investigated, along with their electrochemical properties over time of exposure to two NaCl solutions (0.3% and 3% by weight). All the coated Al surfaces exhibited a water contact angle of 155–158°, i.e., superhydrophobicity. The use of nano-silica suspension significantly enhanced the hydrophobicity of the coated Al. Artificial neural networks were used to provide quantitative understanding in how the microstructure of the treated Al surface contributed to its superhydrophobicity and electrochemical properties. When Ra, total (nano-roughness + micro-roughness) exceeds 450 nm, WCA is greater than 154°, independent of the nano/micro-roughness ratio (RRNM). FESEM and AFM images of these surfaces suggest that a rough two-length-scale hierarchical structure coupled with the low surface energy of fluorosilane topcoat led to the superhydrophobicity of the formed coatings. The coating prepared with the 0.2% nano-silica suspension (vs. other concentrations) featured the highest Young's modulus and the best corrosion protection to the Al substrate in both NaCl solutions.  相似文献   
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