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131.
Teimoor Mohammadi Jamshid Farmani Zahra Piravi-Vanak 《Journal of the American Oil Chemists' Society》2019,96(5):555-569
The simplest and the most cost-effective way of human milk fat substitute (HMFS) production is formulating of suitable vegetable oils at proper ratios. To do this, the D-optimal mixture design was used to optimize the HMFS formulation. The design included 25 formulations made from refined palm olein (35–55%), soybean oil (5–25%), olive oil (5–20%), virgin coconut oil (5–15%), and fish oil (0–10%). Samples were produced in laboratory and characterized in terms of fatty acid and triacylglycerol (TAG) compositions, free fatty acid content, peroxide value, iodine value, and oxidative stability index (OSI). HMFS samples were also compared with Codex Alimentarius (CA) and Iran National Standards Organization (INSO) standards. Each characteristic of HMFS samples was then expressed as a function of ingredient ratio using regression models. Finally, using numerical optimization, four optimized blends (PB1-PB4) were selected, made in the laboratory (HMFS1-HMFS4), characterized, and compared with CA and INSO standards. The properties of all the optimized blends (except the palmitic acid content of HMFS2 and the monounsaturated fatty acid [MUFA] content of HMFS3) met the standards. HMFS4 showed the highest OSI in Rancimat and the lowest oxidation rate in Schaal oven tests. POL (19.53–21.73%), PPO (20.77–21.73%), OOO (9.11–11.16%), and OPO (8.84–9.46%) were the main (totally about 60%) TAG species found in HMFS samples. In conclusion, the HMFS4 formula (55% palm olein, 13.5% soybean oil, 16% refined olive oil, 15% virgin coconut oil, and 0.5% fish oil) was suggested as the best formula for HMFS production. 相似文献
132.
Fatemeh Mohammadi 《Fullerenes, Nanotubes and Carbon Nanostructures》2018,26(4):218-225
Phosphorous-doped carbon nanotubes (PCNTs) was prepared via two-step methodology employing chemical vapor deposition, by using available starting materials and catalyst. First, CNTs was produced from acetylene gas at 750 ºC and then, PCNTs have been prepared with total yield of 44% by recooking of the prepared CNT with Ph3P at 600 ºC. The product was characterized with FESEM, TEM and EDS analyses, which confirmed its nanotube shape and the presence of phosphorous atom. The high thermal stability of the product was obtained from TGA analysis, showing only 16.5% weight loss up to 890 ºC. The Raman spectrum of the product showed the ID/IG ration equal to 0.84. Moreover, the catalytic potency of the product has been examined in ORR electrochemical reaction using CV and LSV diagrams. The results confirmed appropriate catalytic activity and high stability of the product for this process. 相似文献
133.
Shahriyar Ghazanfari Holagh Maghsoud Abdollahi Haghghi Zahra Mohammadi Ata Chitsaz 《国际能源研究杂志》2020,44(13):10126-10154
Fuel cell and renewable-based poly-generation plants (PGPs) are proven as advanced technologies for multiple generation purposes. To limit the greenhouse gas emissions, an innovative PGP generating electricity, cooling, desalinated water, and hydrogen is proposed in the current study. The system consists of a solid oxide fuel cell as a prime mover integrated with a gas turbine, a biomass combustion chamber, an organic Rankine cycle, an ejector refrigeration cycle, a desalination unit, and a proton exchange membrane electrolyzer integrated with solar collectors. As the most effective tools for performance evaluation, exergoeconomic, and environmental analyses have been applied. The system produces electricity of 4.4 MW, refrigeration capacity of 0.16 MW, and desalinated water of 0.96 kg/s. The attained freshwater enters the electrolyzer during 12 daylight hours, leading to hydrogen and sanitary water generation with the values of 1.55 g/s and 0.94 kg/s, respectively. The cost per unit exergy and the total cost rate of the products are 11.28 $/GJ, 223 $/h, correspondingly. Carbon dioxide emission of the system is estimated to be 10.79 kmol/MWh. According to the evaluation, the total cost rate increases with increasing current density and fuel cell inlet temperature and decreasing fuel utilization factor. 相似文献
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Hamid Ezzatpanah Vicente M. Gómez-López Tatiana Koutchma Farnoush Lavafpour Frank Moerman Mohammad Mohammadi Dele Raheem 《Comprehensive Reviews in Food Science and Food Safety》2022,21(2):904-941
Food- and waterborne viruses, such as human norovirus, hepatitis A virus, hepatitis E virus, rotaviruses, astroviruses, adenoviruses, and enteroviruses, are major contributors to all foodborne illnesses. Their small size, structure, and ability to clump and attach to inanimate surfaces make viruses challenging to reduce or eliminate, especially in the presence of inorganic or organic soils. Besides traditional wet and dry methods of disinfection using chemicals and heat, emerging physical nonthermal decontamination techniques (irradiation, ultraviolet, pulsed light, high hydrostatic pressure, cold atmospheric plasma, and pulsed electric field), novel virucidal surfaces, and bioactive compounds are examined for their potential to inactivate viruses on the surfaces of foods or food contact surfaces (tools, equipment, hands, etc.). Every disinfection technique is discussed based on its efficiency against viruses, specific advantages and disadvantages, and limitations. Structure, genomic organization, and molecular biology of different virus strains are reviewed, as they are key in determining these techniques effectiveness in controlling all or specific foodborne viruses. Selecting suitable viral decontamination techniques requires that their antiviral mechanism of action and ability to reduce virus infectivity must be taken into consideration. Furthermore, details about critical treatments parameters essential to control foodborne viruses in a food production environment are discussed, as they are also determinative in defining best disinfection and hygiene practices preventing viral infection after consuming a food product. 相似文献
136.
Amin Pourjabari Zanyar Esmailpoor Hajilak Alireza Mohammadi Mostafa Habibi Hamed Safarpour 《Computers & Mathematics with Applications》2019,77(10):2608-2626
This article investigates the influence of porosity on free and forced vibration characteristics of a nanoshell reinforced by graphene platelets (GPL). The material properties of piece-wise graphene-reinforced composites (GPLRCs) are assumed to be graded in the thickness direction of a cylindrical nanoshell and estimated using a nanomechanical model. In addition, because of imperfection of the current structure, three kinds of porosity distributions are considered. The nanostructure is modeled using modified strain gradient theory (MSGT) which is a size-dependent theory with three length scale parameters. The novelty of the current study is to consider the effects of porosity, GPLRC and MSGT on dynamic and static behaviors of the nanostructure. Considering three length scale parameters ( , , ) in MSGT leads to a better agreement with MD simulation in comparison by other theories. Finally, effects of different factors on static and dynamic behaviors of the porous nanostructure are examined in detail. 相似文献
137.
For the first time, the solubility of β-carotene in pure and ethanol-modified subcritical water (SW) using the static method was determined. The experimental runs were performed at a temperature ranging from 298.15 to 403.15 K and 0–10% (w/w) of ethanol as a modifier at a constant pressure of 5 MPa. Samples were analyzed by UV–vis spectrophotometer. The solubility of β-carotene was found to range from 1.084 × 10−8 to 227.1 × 10−8 mol fractions in the subcritical water in above mentioned conditions. The obtained β-carotene solubility data were correlated using the linear model and modified Apelblat model. The obtained results showed the modified Apelblat model was better for estimating the solubility of β-carotene in SW. The values of the root-mean-square deviation (RMSD) between experimental and correlated data were calculated and used as the index of validity and accuracy for the model. Also, thermodynamic properties of the solution such as the Gibbs free energy of solution, enthalpy, and entropy of solution were estimated. 相似文献
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