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21.
Near- and short-wave IR emission spectra of printed cotton/nylon blend fabrics coated with inorganic compounds in order to tune their diffuse reflectance behavior to the ones with woodland and desert backgrounds are investigated. In this regard, cotton/nylon blend fabrics printed with a four-color digital pattern were used as the substrate, and different concentrations of zirconium and cerium dioxide (ZrO2 and CeO2) with and without citric acid as a cross-linker were loaded on these fabrics using the pad-dry-cure method. The diffuse reflectance of the coated fabrics with various concentrations of nanoparticles and a cross-linker was first measured by near-infrared (NIR) diffuse reflectance spectroscopy (DRS). Then, fabrics with an optimum concentration of nanoparticles and appropriate reflectivity profiles similar to woodland and desert were investigated by field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), washing, and rubbing fastness properties. In general, NIR and short-wave infrared (SWIR) reflectance of fabrics coated with ZrO2 and CeO2 nanoparticles in range of 1% to 1.5% (w/v [%]) was suitable for matching with different environments. According to the findings obtained from the durability test, it was concluded that the washing fastness of the treated fabrics with CeO2 nanoparticles was excellent in both environments. FE-SEM images of the treated fabrics containing ZrO2 and CeO2 indicated that the presence of nanoparticles on the surface of fabrics in woodland patterns was greater than the desert ones. However, the coated fabrics with CeO2 and citric acid in the woodland pattern have shown better dispersion with a mean particle size of 30 to 60 nm. 相似文献
22.
The 1-octyl-3-methylimidazolium chloride, [C_8 mim][Cl] ionic liquid(IL) was used as a novel surfactant in n-heptane/water system. The interfacial tensions(IFT) were measured and corresponding variations were investigated. An IFT reduction of 80.8% was appropriate under the IL CMC of about 0.1 mol·L~(-1) and stronger effects were achieved when magnetite nanoparticles and salts were present profoundly under alkaline p Hs.The equilibrium IFT data were accurately simulated with the Frumkin adsorption model. Hereafter, the saturated surface concentration, equilibrium constant and interaction parameter were obtained and their variations were demonstrated. Further, emulsion stability and contact angle of oil/water interface over quartz surface were studied. The oil/water emulsion stability was hardly changed with nanoparticles; however, the stability of oil/water + IL emulsions was significantly improved. It was also revealed that the presence of sodium and calcium chloride electrolytes fortifies the IL impact, whereas sodium sulfate weakens. From dynamic IFT data and fitting with kinetic models, it was found that the IL migration toward interface follows the mixed diffusion–kinetic control model. Consequently, the IL diffusion coefficient and the appropriate activation energy were determined. 相似文献
23.
Parisa Solhi Sodeif Azadmard‐Damirchi Javad Hesari Hamed Hamishehkar 《International Journal of Dairy Technology》2020,73(1):226-233
The qualitative properties of processed cheese (PC) fortified with different levels of asparagus powder (AP) (0.5%, 1% and 1.5% wt/wt) were evaluated during storage. AP decreased the pH and lipolysis indexes and increased the phenolic content, antioxidant activity and proteolysis of the processed cheeses. AP made the structure of the cheese more elastic, increased the rigidity and decreased the spreadability compared with the control sample, which corresponded to the results obtained using dynamic oscillatory rheometry. The results showed that AP as a rich source of bioactive components could be used for the fortification of processed cheeses. 相似文献
24.
Trigeneration is efficient to supply cooling, heat, and power demands. Also, hydro (pumped) storage with zero fuel costs can increase profit when price-based scheduling problem is solved. The goal of this study is to investigate the effects of electric boiler, hydro storage, and heat storage tank on price-based scheduling problem for hybrid trigeneration (trigeneration-conventional-gas boiler) system. A heuristic algorithm is applied to a power system where in validation case, total cost reduction of 0.63% to 0.91% is reached as compared with reported in literature. The results show that the utilization of electric boiler, hydro storage, and heat storage tank leads to profit improvement by 4.58%. Also, a critical sensitivity analysis is conducted and the results show the significant effects of several factors on scheduling results. 相似文献
25.
26.
Morteza Zandrahimi Javad Vatandoost Hadi Ebrahimifar 《Journal of Materials Engineering and Performance》2012,21(10):2074-2079
Aluminum and titanium are deposited on the surface of steel by the pack cementation method to improve its hot-corrosion and high-temperature oxidation resistance. In this research, coatings of aluminum and titanium and a two-step coating of aluminum and titanium were applied on an AISI 304 stainless steel substrate. The coating layers were examined by carrying out scanning electron microscopy (SEM) and x-ray diffraction (XRD). The SEM results showed that the aluminized coating consisted of two layers with a thickness of 450???m each, the titanized coating consisted of two layers with a thickness of 100???m each, and the two-step coatings of Al and Ti consisted of three layers with a thickness of 200???m each. The XRD investigation of the coatings showed that the aluminized coating consisted of Al2O3, AlCr2, FeAl, and Fe3Al phases; the titanized layers contained TiO2, Ni3Ti, FeNi, and Fe2TiO5 phases; and the two-step coating contained AlNi, Ti3Al, and FeAl phases. The uncoated and coated specimens were subjected to isothermal oxidation at 1050?°C for 100?h. The oxidation results revealed that the application of a coating layer increased the oxidation resistance of the coated AISI 304 samples as opposed to the uncoated ones. 相似文献
27.
Farideh Namvar Suhaila Mohamed Samaneh Ghasemi Fard Javad Behravan Noordin M. Mustapha Noorjahan Banu M. Alitheen Fauziah Othman 《Food chemistry》2012
The edible red seaweed Eucheuma cottonii is abundantly cultivated for carrageenan production. This study investigated the effects of dietary E. cottonii polyphenol-rich extract (ECME) on breast cancer. In vitro assays showed that ECME was antiproliferative against oestrogen-dependent MCF-7 and oestrogen-independent MB-MDA-231 human breast-cancer cells (IC50 values of 20 and 42 μg/ml, respectively) but was non-toxic to normal cell lines. The ECME (150 and 300 mg/kg BW) was fed to female rats and, after 4 weeks, rat mammary tumour was induced using LA7 cells (inoculated subcutaneously). The ECME inhibited tumour development and erythrocyte lipid peroxidation in the cancer-induced rats, dose-dependently. It showed anti-oestrogenic effects on the rat estrous cycle and serum hormone levels. Electron microscopy and histopathology observations confirmed apoptosis in the rat mammary tumours. The polyphenol-rich ECME was tumour-suppressive via apoptosis induction, downregulating the endogenous oestrogen biosynthesis, and improving antioxidative status in the rats. 相似文献
28.
The effect of air temperature (AT) and slice thickness (ST) on the quality and drying kinetics of tomato slices were studied. The drying period of tomato slices to reach the moisture content of 15% (wb) ranged from 2.6 to 18.7 h. The water diffusivity, activation energy, and resistance to diffusion ranged from 1.4 × 10?10 to 2.8 × 10?9 m2/s, 21.25 to 23.4 kJ/mol, and from 939 to 4590 m2 s/kg, respectively. Drying had a significant effect on ascorbic acid, soluble solid, acidity, and pH (P = 0.01). The ascorbic acid degradation was greatly influenced by ST. The results show that time-temperature superposition technique (TTST) was very efficient in the modeling of the drying process. The proposed TTST provides a novel alternative in curve-fitting exercise of drying data. Neural networks also showed favorable performance in estimating the drying functions. 相似文献
29.
Javad Safaei-Ghomi Marzieh Kiani Abolfazl Ziarati Hossein Shahbazi-Alavi 《Journal of Sulfur Chemistry》2014,35(4):450-457
ZrP2O7 nanoparticles as an efficient catalyst have been used for the preparation of benzopyrano[2,3-b]pyridines from the four-component condensation reaction of salicylalde-hydes, thiols, and 2 equiv. of malononitrile under reflux conditions in ethanol in excellent yields and short reaction times. 相似文献
30.
Cox W. Miles; Fadardi Javad Salehi; Pothos Emmanuel M. 《Canadian Metallurgical Quarterly》2006,132(3):443
Decisions about using addictive substances are influenced by distractions by addiction-related stimuli, of which the user might be unaware. The addiction-Stroop task is a paradigm used to assess this distraction. The empirical evidence for the addiction-Stroop effect is critically reviewed, and meta-analyses of alcohol-related and smoking-related studies are presented. Studies finding the strongest effects were those in which participants had strong current concerns about an addictive substance or such concerns were highlighted through experimental manipulations, especially those depriving participants of the substance. Theories to account for addiction-related attentional bias are discussed, of which the motivational theory of current concerns appears to provide the most complete account of the phenomenon. Recommendations are made for maximizing the precision of the addiction-Stroop test in future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献