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Alireza Baghban Amin Piri Mostafa Lakzaei Mohammad Baghban 《Petroleum Science and Technology》2019,37(11):1231-1237
The increasing global energy demand and declination of oil reservoir in recent years cause the researchers attention focus on the enhancement of oil recovery approaches. One of the extensive applicable methods for enhancement of oil recovery, which has great efficiency and environmental benefits, is carbon dioxide injection. The CO2 injection has various effects on the reservoir fluid, which causes enhancement of recovery. One of these effects is extraction of lighter components of crude oil, which straightly depends on solubility of hydrocarbons in carbon dioxide. In order to better understand of this parameter, in this study, Least squares support vector machine (LSSVM) algorithm was developed as a novel predictive tool to estimate solubility of alkane in CO2 as function of carbon number of alkane, carbon dioxide density, pressure, and temperature. The predicting model outputs were compared with the extracted experimental solubility from literature statistically and graphically. The comparison showed the great ability and high accuracy of developed model in prediction of solubility. 相似文献
63.
Effect of pretreatments and drying methods on physico‐chemical,sensory characteristics and nutritional value of oyster mushroom 下载免费PDF全文
Ahmed R. M. Maray Mostafa K. Mostafa Alaa El‐Din M. A. El‐Fakhrany 《Journal of Food Processing and Preservation》2018,42(1)
This study was aimed to evaluate the effect of pretreatments and drying methods on the chemical, physico‐chemical, sensory characteristics and nutritional value of oyster mushroom. Chemical analysis of oyster mushroom (OM) showed that the values content were increased by many times when calculated on dry weight basis. Nine treatments of dried mushroom powders (DMP) were prepared using three drying methods (hot air drying, vacuum drying, and sun drying). Also, three pretreatments of each method of drying were used (untreated, blanching by steaming without or with steeped in 0.5% citric acid solution for 30 min).The results and statistical analysis revealed that, sun dried oyster mushroom samples (without pretreatments) were found to be the best. The DMP samples resulting of the sun drying had a highest physico‐chemical properties, sensory evaluation scores, and contents of the mineral elements and amino acids as compared to other pretreatments and drying methods.
Practical applications
Fresh mushrooms have high water content, high enzymatic activity and hence are highly perishable. Thus, in this study nine treatments of dried mushroom powders (DMP) were prepared using three drying methods (hot air drying, vacuum drying and sun drying).Also, three pretreatments of each method of drying were used (untreated, blanching by steaming without or with steeped in citric acid).The DMP samples (untreated) resulting of the sun drying were better than other pretreatments and drying methods regarding quality attributes. 相似文献64.
Mohammad Hosein Bina Mostafa Jamali Morteza Shamanian Hamed Sabet 《The International Journal of Advanced Manufacturing Technology》2014,75(9-12):1371-1379
In this work, the effect of weld current on joining capability of austenitic stainless steel (AISI 304) and ferritic stainless steel (AISI 430) sheets with application of resistance spot welding process was investigated. Macrostructure, microstructure, microhardness, tensile shear strength, and failure mode of welded materials were evaluated for different weld currents. The values of weld current were 2.5, 3.75, and 5 kA. It was found that when the weld current increased, the nugget size and the weld strength were increased. Two distinct failure modes including interfacial and pullout were observed during tensile shear test. Finally, an adequate weld current was obtained. 相似文献
65.
Mehraneh Ghavami Mostafa Aghbolaghy Jafar Soltan Ning Chen 《Frontiers of Chemical Science and Engineering》2020,14(6):937
Volatile organic compounds (VOCs) are among the major sources of air pollution. Catalytic ozonation is an efficient process for removing VOCs at lower reaction temperature compared to catalytic oxidation. In this study, a series of alumina supported single and mixed manganese and cobalt oxides catalysts were used for ozonation of acetone at room temperature. The influence of augmenting the single Mn and Co catalysts were investigated on the performance and structure of the catalyst. The manganese and cobalt single and mixed oxides catalysts of the formula Mn10%-CoX and Co10%-MnX (where X= 0, 2.5%, 5%, or 10%) were prepared. It was found that addition of Mn and Co at lower loading levels (2.5% or 5%) to single metal oxide catalysts enhanced the catalytic activity. The mixed oxides catalysts of (Mn10%-Co2.5%) and (Mn10%-Co5%) led to acetone conversion of about 84%. It is concluded that lower oxidation state of the secondary metal improves ozone decomposition and oxidation of acetone. 相似文献
66.
Mohammad Khajeh Mehrizi Mostafa Jokar Tayebah Sadeghyan Mohammad Erfan Azizi Mohammad Reza Rahmani 《Coloration Technology》2023,139(4):385-394
The alginate thickener is the thickener frequently used for reactive printing of textile. The thickener responds with reactive pigments and thus does not lead to the fabric composition becoming stiffer. In this study, we prepared oxidised natural guar gum with hydrogen peroxide, sodium hypochlorite and sodium hydroxide. All other polysaccharides comprise reactive hydroxyl units with a stronger reactivity that must be replaced if they are to be used in reactive printing. Guar derivatives were synthesised and verified using Fourier-transform infrared (FTIR) spectroscopy. Natural thickeners, synthetic guar gum derivatives, have been employed in textile printing technique. In comparison to other synthetic thickeners, modified environmental guar gum polymer has been shown to be an ecologically friendly and low-cost thickener. Cotton fabric printed with modified guar thickening with hydrogen peroxide has even stronger colour strength than fabric printed with sodium alginate thickener, which is highly favourable. Penetration properties, colour value, colour strength, colour fastness to washing, light and rubbing was compared with alginate thickener (readily available on the market). Guar gum thickeners showed enhanced features versus sodium alginate for reactive printing. Partially replaced guar gum is an appropriate option due to the colour and physical properties. 相似文献
67.
In this work, styrene‐maleic anhydride (St‐MA) copolymer was successfully grafted onto poly(vinyl chloride) (PVC) by means of chemical method in cyclohexanone medium. In this manner, the effects of various parameters such as total monomer content, monomers ratio, and initiator concentration on the grafting percentage (GP) and acid value (AV) were examined. The graft copolymers were characterized by Fourier‐transform infrared and nuclear magnetic resonance spectroscopy methods. Afterward, the cross‐linking reaction was carried out through MA hydrolysis and condensation reaction between maleic acid and produced diamines, by toluene diisocyanate (TDI) at the presence of hot water. The results showed that the GP and AV of PVC‐g‐(St‐MA) copolymers were considerably higher than those of PVC‐g‐MA and PVC‐g‐St with significant molecular weight. A gel content of 56% was attained with 1 phr TDI in PVC‐g‐(St‐MA) copolymer. The glass transition temperatures and mechanical properties of PVC‐g‐(St‐MA) samples were increased compared to pure PVC. Cross‐linked PVC‐g‐(St‐MA) showed improved mechanical properties than other samples, but the glass transition temperature of PVC backbone in this cross‐linked copolymer was disappeared due to its heavily dense structure. J. VINYL ADDIT. TECHNOL., 25:377–384, 2019. © 2019 Society of Plastics Engineers 相似文献
68.
SPEEK/cSMM membrane for simultaneous electricity generation and wastewater treatment in microbial fuel cell 下载免费PDF全文
69.
70.
Mojtaba Shamsipur Mostafa Najafi Mohammad-Reza Milani Hosseini 《Journal of Applied Electrochemistry》2013,43(10):1027-1033
Electrocatalytic oxidation of methanol and some other primary alcohols on a glassy carbon electrode modified with multi-walled carbon nanotubes and nano-sized nickel oxide (GCE/MWNT/NiO) was investigated by cyclic voltammetry and chronoamperometry in alkaline medium. The results were compared with those obtained on a nickel oxide-modified glassy carbon electrode (GCE/NiO). Both the electrodes were conditioned by potential cycling in the range of 0.1–0.6 V versus Ag/AgCl in a 0.10 M NaOH solution. The effects of various parameters such as scan rate, alcohol concentration, thickness of NiO film, and real surface area of the modified electrodes were also investigated and compared. It was found that the GCE/MWNT/NiO-modified electrode possesses an improved electrochemical behavior over the GC/NiO-modified electrode for methanol oxidation. 相似文献