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271.
White JB Beckford J Yadegarynia S Ngo N Lialiutska T d'Alarcao M 《Food chemistry》2012,131(4):1453-1459
A common feature of both apoptosis and inflammation is the activation of caspases. Caspases are aspartate-directed cysteine proteases that have numerous cellular targets. It has been discovered that several flavonoids are inhibitors of caspases. Flavonoids are members of a family of polyphenolic compounds from plants that have many biological properties, one of which is the ability to induce cell death. Some flavonoids are selective inhibitors of particular caspases. Since some of the inhibitory flavonoids are nevertheless cytotoxic, these results suggest that flavonoid-induced cell death may be occurring through a non-classical apoptosis pathway that is not dependent on caspase activity. 相似文献
272.
Seyed Mohammad Taghi Gharibzahedi Seyed Mohammad MousaviManouchehr Hamedi Mehran Ghasemlou 《Food Hydrocolloids》2012,26(1):293-301
The effect of Arabic gum content (5-10% w/w) and walnut-oil concentration (3-6% w/w) on properties of prepared walnut oil/water emulsion, including turbidity loss rate, density, size index, particle size and stability, was investigated using response surface methodology (RSM). For each response, a second-order polynomial model with high coefficient of determination (R2) values ranging from 0.907 to 0.989 was developed using multiple linear regression analysis. The lack of significant difference between the experimental and predicted values proved the adequacy of response surface equations for describing the physical changes of emulsions. An increase of Arabic gum content in range and initial concentration of walnut oil were associated with high emulsion stability and minimum droplet size. It can be concluded that RSM can determine the most suitable formulation (3% w/w walnut oil and 9.62% w/w Arabic gum) to achieve the highest stability in a developed beverage emulsion based on walnut oil. 相似文献
273.
Amir Hosein Saeedi Dehaghani Bahareh Keshavarz Seyed Ali Mousavi Dehghani 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(11):1360-1371
The purpose of this study is to explore the impact of additives on the displacement of the onset point of asphaltene precipitation in crude oil using the interfacial tension measurement method, based on the examined oil has been taken from Iran reservoirs. The experimental results suggest that the addition of surfactants of dodecyl benzene sulfonic acid (DBSA) and coconut diethanolamide (CDEA) to the oil has triggered the onset of asphaltene precipitation. These findings imply that CDEA has a more effective role in preventing asphaltene precipitation. Also, it was observed that increasing the concentration of the surfactants has led to obtaining greater results. Finally, critical micelle concentration was calculated to be 5000 and 4700 ppm in the cases of CDEA and DBSA, respectively. 相似文献
274.
There is a great variety of two‐phase models in numerical simulations. The performance of each model complicates the numerical simulation of boiling. The challenge of the right choice of heat and mass transfer models makes this type of problem more complicated. In this research work, the volume of the fluid two‐phase model has been used to simulate the film boiling of saturated liquid. The geo‐reconstruction method also reconstructs the interface of two phases. The models of the sharp interface, Lee and Tanasawa have been employed among the available models for calculating the phase change rate and the source terms of the equations. The Numerical solver of the phase‐change is verified through the Stefan one‐dimensional vaporizing problem. Correct empirical coefficients used in both Lee and Tanasawa models are presented. Bubble detachment time, flow pattern, the periodic Nusselt number, and the bubble form have been investigated in all three phase change models. Two Berenson and Klimenko experimental correlations have been used for verification of Nusselt number derived from simulations. The Nusselt number shows a proper fit with the Klimenko's Nusselt number. Obtained Nusselt number demonstrates the Lee model is more precise than other phase change models in simulating of film boiling on the flat plate. 相似文献
275.
Improving energy productivity of sunflower production using data envelopment analysis (DEA) approach 总被引:1,自引:0,他引:1
Avval SH Rafiee S Jafari A Mohammadi A 《Journal of the science of food and agriculture》2011,91(10):1885-1892
BACKGROUND: Efficient use of energy in agriculture is one of the conditions for sustainable agricultural production. This study applies the data envelopment analysis (DEA) approach to the data of 95 randomly selected farms to investigate the technical and scale efficiencies of farmers with respect to energy use for sunflower production in Golestan province, Iran. The study also helps to identify the wasteful usage and the optimum level of energy from different inputs. RESULTS: According to the results of DEA models, about 36% of farmers were found to be technically efficient and the mean efficiency of sunflower producers was found to be 0.87 and 0.96 under the constant and variable returns to scale assumptions respectively. The optimum energy requirement was calculated as 8448.3 MJ ha?1; accordingly, a potential reduction of 10.8% (1020.3 MJ ha?1) in total energy input could be achieved by raising the performance of farmers to the highest level. CONCLUSION: Applying a better machinery management technique and conservation tillage methods, application of fertilisers by performance monitoring and utilisation of alternative sources of energy such as compost and chopped residues may be the pathways for improving energy productivity and reducing the environmental footprint. Copyright © 2011 Society of Chemical Industry 相似文献
276.
Seyed Ahmad Hani Tabaie Zavareh Fatemeh Ardestani 《International Journal of Dairy Technology》2020,73(3):585-593
The effect of a chitosan coating and Mentha aquatica L. essence on Iranian white cheese was investigated. Results showed 100% inhibition of Escherichia coli growth using 1.5% essence after 10 days. After 15 days of incubation, the Staphylococcus aureus population was reduced by 44.2%, 70.0%, and 88.5% using 0.5, 1.0 and 1.5% essence, respectively. After 15 days, Listeria monocytogenes growth was inhibited by 63.84%, 70.12%, and 85.9% using 0.5, 1.0, and 1.5% essence, respectively. Inhibition zone diameter studies also confirmed the antibacterial effects of applied coating against all the above‐mentioned bacteria in Iranian white cheese. 相似文献
277.
Seyed Mohammad Bagher Hashemi 《International Journal of Food Science & Technology》2018,53(3):564-570
The effects of pulsed and continuous ultrasound treatment on microbiological and physiological quality of Mirabelle plum fruit were investigated. Freshly harvested Mirabelle plum was treated with 30‐kHz pulsed and continuous ultrasound at 20 °C for 0, 15, 30, 45 and 60 min and subsequently stored at 4 °C for 10 days. The total count of bacteria, total fungi, decay index, titratable acidity (TA), total soluble solids (TSS), colour, texture, ascorbic acid content and total phenolics was measured. The results showed that pulsed and continuous ultrasonic treatment significantly (P < 0.05) reduced the number of microorganisms and improved the quality of Mirabelle plums during storage. Increasing pretreatment time enhanced the positive effects of pulsed and continuous ultrasound. Also, in terms of the total count of bacteria, total fungi, titratable acidity and total phenolics, the pulsed and continuous ultrasound did not show a significant difference (P < 0.05). However, pulsed ultrasound was better compared to continuous mode in preservation of TSS, colour, texture and ascorbic acid content of the fruit during storage. Our results demonstrated that pulsed ultrasound is an appropriate method for improving safety and maintaining the quality of Mirabelle plum fruit. 相似文献
278.
Trichloroethylene adsorption by fibrous and granular activated carbons: aqueous phase, gas phase, and water vapor adsorption studies 总被引:2,自引:0,他引:2
The important adsorption components involved in the removal of trichloroethylene (TCE) by fibrous and granular activated carbons from aqueous solutions were systematically examined. Namely, adsorption of TCE itself (i.e., TCE vapor isotherms), water molecules (i.e., water vapor isotherms), and TCE in water (i.e., TCE aqueous phase isotherms) were studied, side-by-side, using 20 well-characterized surface-modified activated carbons. The results showed that TCE molecular size and geometry, activated carbon surface hydrophilicity, pore volume, and pore size distribution in micropores control adsorption of TCE at relatively dilute aqueous solutions. TCE adsorption increased as the carbon surface hydrophilicity decreased and the pore volume in micropores of less than 10 A, especially in the 5-8 A range, increased. TCE molecules appeared to access deep regions of carbon micropores due to their flat geometry. The results indicated that characteristics of both adsorbate (i.e., the molecular structure, size, and geometry) and activated carbon (surface hydrophilicity, pore volume, and pore size distribution of micropores) control adsorption of synthetic organic compounds from water and wastewaters. The important micropore size region for a target compound adsorption depends on its size and geometry. 相似文献
279.
Mahmoud Omid Mahmoud SoltaniMohammad Hadi Dehrouyeh Seyed Saeid MohtasebiHojat Ahmadi 《Journal of food engineering》2013
The main purpose of this research was design and development of an intelligent system based on combined fuzzy logic and machine vision techniques for grading of egg using parameters such as defects and size of eggs. The detected defects were internal blood spots, cracks and breakages of eggshell. The Hue-Saturation-Value (HSV) color space was found useful in obtaining visual features during Image Processing (IP) stage. The fuzzy inference system (FIS) was designed based on triangular and trapezoidal membership functions, fuzzy rules with logical operator of AND inference system of Mamdani and method of center average for defuzzifier. The evaluation results of IP algorithms showed that use of IP technique has good performance for defects and size detection. The Correct Classification rate (CCR) was 95% for size detection, 94.5% for crack detection and 98% for breakage detection. The overall accuracy FIS model in grading of the eggs was 95.4. 相似文献
280.
Encapsulation of Zataria multiflora Bioss. Essential Oil into Nanoliposomes and in Vitro Antibacterial Activity Against Escherichia coli O157:H7 下载免费PDF全文