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排序方式: 共有278条查询结果,搜索用时 46 毫秒
71.
Li Zixiang Dey Nilanjan Ashour Amira S. Tang Qiuhua 《Neural computing & applications》2018,30(9):2685-2696
Neural Computing and Applications - Robotics are extensively utilized in modern industry to replace human labor and achieve high automation and flexibility. In order to produce large-size products,... 相似文献
72.
73.
Mette Korshøj Jørgen H. Skotte Caroline S. Christiansen Pelle Mortensen Jesper Kristiansen Christiana Hanisch 《Ergonomics》2014,57(2):247-253
The validity of inclinometer measurements by ActiGraph GT3X+ (AG) accelerometer, when analysed with the Acti4 customised software, was examined by comparison of inclinometer measurements with a reference system (TrakStar) in a protocol with standardised arm movements and simulated working tasks. The sensors were placed at the upper arm (distal to the deltoid insertion) and at the spine (level of T1-T2) on eight participants. Root mean square errors (RMSEs) values of inclination between the two systems were low for the slow- and medium-speed standardised arm movements and in simulated working tasks. Fast arm movements caused the inclination estimated by the AG to deviate from the reference measurements (RMSE values up to ~10°). Furthermore, it was found that AG positioned at the upper arm provided inclination data without bias compared to the reference system. These findings indicate that the AG provides valid estimates of arm and upper body inclination in working participants. 相似文献
74.
Eser Ayanoglu Simeon Popov J. M. Kornprobst Amira Aboud-Bichara Carl Djerassi 《Lipids》1983,18(11):830-836
The phospholipids of the demospongeHigginsia tethyoides are shown to have at least 16 long-chain α-methoxy acids, which represent a new class of fatty acids. Among them are the
saturated α-methoxy acids containing 19–24 carbon atoms. The monounsaturated compounds are 2-OMe-Δ17-24:1, 2-OMe-Δ18-25:1, 2-OMeΔ19-26:1 and 2-OMe-Δ21-28:1. The major diunsatured ones were shown to be 2-OMe-Δ5, 19-26:2 and 2-OMe-Δ7, 21-28:2. Small amounts of 2-OMe-23∶1, 2-OMe-26∶3; 2-OMe-27∶1 and 2-OMe-28∶3 were also encountered. Structures of the minor monounsaturated
compounds were tentatively assigned as 2-methoxy-16-tricosenoic acid and 2-methoxy-20-heptacosenoic acids. The double bonds
of the fatty acids show all-cis configuration. Circular dichroism measurements indicate an R-configuration for the α-methoxy acids. The major component of
the total phospholipid acid mixture is 5,9,23-triacontatrienoic acid. Possible biosynthetic routes to these unusual phospholipid
acids are discussed. The major phospholipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine. The
distribution of fatty acids among the phospholipids was also investigated. 相似文献
75.
Al‐Sayed Al‐Sherbini Mostafa M. H. Khalil Hanaa Hussein El‐Sayed Amira Fawzy Soliman 《Journal of Food Processing and Preservation》2018,42(1)
Gold nanoparticles (AuNPs) as preservatives add with variable concentrations to corn oil to may improve the shelf life. AuNPs was prepared by pyrolysis in oleic acid then sample was characterized by transmission electron microscope and UV spectroscopy. Rancidity analyses and microbiological properties were performed through storage periods. The results showed that AuNPs decreases total bacterial count and chemical analyses except iodine value but shelf life increases compared to control sample.
Practical applications
It is of interest to know that, gold nanoparticles not only have the antibacterial function, but also have good safe guarantee in human edible and touchable fields. It is nontoxic, odorless, and safe having passed the FDA attestation in the United States. The future prospective of these nanomaterials give a wide range of chances for the development of innovative products and applications in the food system. 相似文献76.
77.
Emna Behija Saafi Amira El Arem Manel Issaoui Mohamed Hammami & Lotfi Achour 《International Journal of Food Science & Technology》2009,44(11):2314-2319
Fruits of date palm ( Phoenix dactylifera L.) are consumed throughout the world and are a vital component of the diet in most Arabian countries. This study has been carried out to evaluate the total phenolic content and the antioxidant activity of four date palm fruit varieties grown in Tunisia. All measurements were made at the 'tamar' stage-the final stage of fruit ripeness. The date varieties were found to be rich in total phenolic ranging from 209.42 mg of equivalent gallic acid/100 g fresh weight in Kentichi to 447.73 mg equivalent gallic acid/100 g fresh weight in Allig. The date varieties studied were characterised by a high antioxidant activity ranging from 866.82 for the Deglet Nour to 1148.11 μmol Equivalent Trolox/100 g fresh weight for Khouet Kenta by the ABTS method. In fact, the DPPH method revealed that Allig having the lowest antioxidant activity (0.72) followed by Deglet Nour (1.53), Kentichi (1.68) and Khouet Kenta variety (1.96). This study suggest that Tunisian date palm fruit may serve as a good source of natural antioxidants and could potentially be considered as a functional food ingredient. 相似文献
78.
Olumuyiwa S. Falade Oluwatoyin O. Adepoju Olanrewaja Owoyomi & Steve R. Adewusi 《International Journal of Food Science & Technology》2008,43(1):24-29
Two essential amino acids (methionine and tryptophan); anti‐nutritional factors (tannin and trypsin inhibitor) and toxic elements (Pb, Cd, Ni, As, Hg and Cr) were determined spectrophotometrically from five edible wild mushrooms. The tryptophan content was between 1.00 and 1.82 g (100 g)?1 but methionine was low at 0.26–1.38 g (100 g)?1. Tannin content was high (30.3–40.0 mg g?1) but trypsin inhibitor was low (22.0–39.5 TIU g?1). Trace elements analysis reviled Pb (0.34–5.06 mg kg?1) to be the highest of all the trace elements. Cd was (0.06–1.70 mg kg?1), Ni (0.26–2.08 mg kg?1), As (0.17–0.92 mg kg?1), Hg (0.01–0.05 mg kg?1) and Cr (0.04–0.22 mg kg?1). These mushrooms are nutritious but must be well processed to eliminate or at least reduce the levels of tannin and Pb to improve their nutritional values. 相似文献
79.
Mahmoud Rahmati Saeid Rajabzadeh Amira Abdelrasoul Yuki Kawabata Tomohisa Yoshioka Hideto Matsuyama Toraj Mohammadi 《应用聚合物科学杂志》2021,138(44):51304
Recently, nano-filtration membranes are made by the reaction between a reactive functional group on the surface of a tight ultrafiltration membrane and a charged branched polymer. This reaction makes the selective layer of the nanofiltration membrane, which plays an essential role in membrane performance. A molecular dynamics simulation with a reactive force field was used to investigate the reaction of carboxylated polyethersulfone as the functional group of the ultrafiltration membrane with polyethyleneimine. Experimental elucidation of the reaction between the PEI amine and carboxyl groups is challenging, and an MD simulation was thus employed. Furthermore, the simulation results show that the PEI and carboxylated polyethersulfone polymers react with each other in a temperature-dependent manner. While no reaction occurs at 298 K, carboxylated polyethersulfone and PEI begin to react when the temperature is increased from 298 to 323 K. Furthermore, a reversible reaction was observed with a subsequent increase in temperature to 353 K. 相似文献
80.