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71.
Emad Karrar Isam A. Mohamed Ahmed Muhammad Faisal Manzoor Frederick Sarpong Wei Wei Xingguo Wang 《European Journal of Lipid Science and Technology》2021,123(3):2000104
Cucurbitaceae family seeds are mostly discarded as agro-industrial wastes. Gurum (Citrullus lanatus var. colocynthoide) is an underutilized wild cucurbit plant, closely related to desert watermelon, which is grown abundantly in some African countries. Gurum seeds can play a significant role in health and nutrition due to their high oil content. This review describes the nutritional composition of gurum seeds and their oil profile. Gurum seeds are a good source of oil (27–35.5%), fiber (26–31%), crude protein (15–18%), and carbohydrates (14–17%). Gurum seeds oil is extracted by supercritical CO2 (SFE), screw press, and solvent extraction techniques. The gurum seeds oil is composed of unsaturated fatty acids with a high proportion of linoleic acid (C18:2) and oleic acid (C18:1). Gurum seeds oil contains various bioactive compounds, such as tocopherols, phytosterols, and polyphenols. It is reported that solvent extraction gives a higher yield than the screw press and SFE, but the SFE is preferred due to safety issues. More studies are required for producing better quality gurum seeds oil by using novel extraction techniques that can increase oil yield. 相似文献
72.
Zaki I. Zaki Mohsen Al-qahtani Saad H. Alotaibi Mohamed H. El-Sadek Hesham Ahmed Yasser M. Z. Ahmed 《International Journal of Applied Ceramic Technology》2021,18(5):1502-1509
Composites of NbC/ZrO2 reinforced with different weight ratios of Cr metal were prepared by dynamic compaction combustion from a blend of Nb2O5–Zr–Cr powders. Factors controlling the synthesis process, the microstructure, and the mechanical properties of the samples, such as Cr wt% and the compression loads were studied. The samples were characterized by XRD, SEM, porosity, and hardness measurements. The porosity value of the sample with no additives was high and reached 31.6 vol%. A sudden decrease in the sample porosity to 2.4 vol % was noticed for the sample containing 3.0 wt% of Cr. A high-density sample with less than 2.0 vol % porosity and maximum hardness of 1038 HV was produced using 5.0 wt% Cr under 300 MPa compression load. Detailed thermodynamic calculations for the effect of Cr additives on the physicochemical properties of the system were introduced. 相似文献
73.
Elbasuney Sherif Hamed Abdelaziz Yehia M. Ramzy Hesham Abdelgawad Ahmed Gobara Mohamed Mokhtar Mohamed 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(9):3665-3676
Journal of Inorganic and Organometallic Polymers and Materials - Surface oxygen of oxide catalyst has low coordination number; they are negatively charged. Surface oxygen can act active site for... 相似文献
74.
V. Devadoss M. Noel K. Jayaraman C. Ahmed Basha 《Journal of Applied Electrochemistry》2003,33(3-4):319-323
The redox behaviour of Mn3+/Mn2+, Co3+/Co2+ and Ce4+/Ce3+ mediators commonly used in indirect oxidation of organic compounds were evaluated in methane sulfonic acid on a glassy carbon working electrode employing cyclic voltammetry. Manganic methanesulfonate exhibits higher instability in dilute methanesulfonic acid. The solid MnO2 formed during disproportionation on the glassy carbon electrode further affects the reproducibility. Cobaltic methanesulfonate formation occurs only at oxygen evolution region rendering the overall oxidation process less efficient. Ceric methane sulfonate formation is highly efficient over a wide acid concentration range. Ceric methanesulfonate can also be employed over a wide temperature range to oxidize different aromatic compounds. 相似文献
75.
A. H. M. Ahmed H. F. W. Taylor 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1969,19(9):245-246
The stability relationships of xonotlite, foshagite and hillebrandite relative to kilchoanite and calcio-chondrodite have been studied under saturated steam pressures at 180° and 250°. Kilchoanite was unstable relative to xonotlite plus hillebrandite at 180°, or to foshagite plus hillebrandite at 250°; calcio-chondrodite was unstable relative to hillebrandite plus some more lime-rich phase, possibly Ca(OH)2, at both temperatures. Foshagite was stable relative to xonotlite plus hillebrandite at 250°, but unstable relative to these phases at 180°. 相似文献
76.
A. H. Moinuddin Ahmed Lesley S. Dent Glasser 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1973,23(6):457-463
α-BaO.Al2O3.4H2O has been synthesised and studied by infrared, X-ray and thermal analytical techniques. The compound of approximate formula BaO.Al2O3.0.5H2O, described in Part III, forms as a dehydration product, and appears to be identical with the compound β-BAH2 described by other workers. A possible explanation for the discrepancy in water content is discussed. 相似文献
77.
Members of health social networks may be susceptible to privacy leaks by the amount of information they leave behind. The threat to privacy increases when members of these networks reuse their pseudonyms in other social networks. The risk of re‐identifying users from such networks requires quantitative estimates to evaluate its magnitude. The estimates will enable managers and members of health social communities to take corrective measures. We introduce a new re‐identification attack, the social network attack, that takes advantage of the fact that users reuse their pseudonyms. To demonstrate the attack, we establish links between MedHelp and Twitter (two popular social networks) based on matching pseudonyms. We used Bayesian networks to model the re‐identification risk and used stylometric techniques to identify the strength of the links. On the basis of our model 7‐11. 8% of the MedHelp members in the sample population who reused their pseudonyms in Twitter were re‐identifiable compared with 1% who did not. The risk estimates were measured at the 5% risk threshold. Our model was able to re‐identify users with a sensitivity of 41% and specificity of 96%. The potential for re‐identification increases as more data is accumulated from these profiles, which makes the threat of re‐identification more serious. 相似文献
78.
Xu Zhou YanTao Zhou KenLi Li Ahmed Sallam Keqin Li 《The Journal of supercomputing》2014,69(2):976-1005
The tile assembly model is a novel biological computing model where information is encoded in DNA tiles. It is an efficient way to solve NP-complete problems due to its scalability and parallelism. In this paper, we apply the tile assembly model to solve the minimum and exact set cover problems, which are well-known NP-complete problems. To solve the minimum set cover problem, we design a MinSetCover system composed of three parts, i.e., the seed configuration subsystem, the nondeterministic choice subsystem, and the detection subsystem. Moreover, we improve the MinSetCover system and propose a MinExactSetCover system for solving the problem of exact cover by 3-sets. Finally we analyze the computation complexity and perform a simulation experiment to verify the effectiveness and correctness of the proposed systems. 相似文献
79.
Ahmed A. Busnaina 《The Journal of Adhesion》1995,51(1):167-180
Recent progress in particle capture and rebound and its effect on the adhesion force is reviewed in this paper. Particles rebound when the incident velocity is greater than a characteristic critical velocity. Lower impaction velocity particles experience elastic and plastic deformation. Recent models for particle rebound and capture are discussed and evaluated in terms of their restrictive assumptions and results. Recent experimental data of particle rebound and capture is also discussed, as is the hydrodynamic removal of captured particles. The removal of particles occurs when the applied hydrodynamic removal force overcomes the adhesion force. The effect of adhesion-induced deformation on the removal of particles is introduced and discussed. 相似文献
80.
Rates of natural convection mass transfer were determined at vertical cones by measuring the limiting current of the cathodic deposition of copper from acidified copper sulphate solution. Variables studied were cone position (upward or downward apex), apex angle of the cone and copper sulphate concentration. For vertical cones with upward pointing apex the data were represented in the range 4.9×1010<(Sc Gr)<9×1011 by the equation: $$Sh = 0.128 (Sc Gr)^{0.33}$$ For vertical cones with downward pointing apex the data fit the equation: $$Sh = 0.877 (Sc Gr)^{0.25}$$ 相似文献