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31.
Mokhtar Guissous Yveline Le Dréau Hasna Boulkhroune Toufik Madani Jacques Artaud 《Journal of the American Oil Chemists' Society》2018,95(3):267-281
Differences in triacylglycerol, fatty acid, squalene, and tocopherol compositions were demonstrated between 8 varieties of virgin olive oils (Aberkane, Aguenaou, Aharoun, Aimel, Bouchouk Guergour, Bouichret, Chemlal, and Sigoise) from Petite Kabylie area, north eastern Algeria. Fatty acid and triacylglycerol morphotypes characterized each variety. A principal component analysis, based on triacylglycerol, fatty acid, and squalene compositions, differentiates between varieties. Minor fatty acids and squalene, usually not taken into account individually in authentication studies, are strongly involved in this differentiation, whereas the discriminant power of tocopherols is weak. Soft Independent Modeling of Class Analogy classification using chemical compositions as variables showed a high potential to authenticate the varietal origin of Algerian virgin olive oils. 相似文献
32.
33.
The dependence of the attenuation of both gamma rays and neutrons on lead concentration in leaded-natural rubber composites incorporated with paraffin wax and boron carbide as radiation shields was investigated. Moreover, the dc conductivity and swelling characteristics of the rubber vulcanizates and the effect of aging on them were studied. It was found that samples of 18 mm thickness incorporated with 20 phr of B4C and 60 phr of paraffin wax can reduce the fast neutron beams by about 50%. For slow neutrons, the reduction was about 46%. The attenuated γ-dose increased exponentially with increasing lead content. 相似文献
34.
Rizwan Ul Haq Zakia Hamouch S.T. Hussain Toufik Mekkaoui 《International Journal of Hydrogen Energy》2017,42(24):15925-15932
Main objective of this frame work is to establish the modeling and simulation of mix convection flow along a vertically heated sheet filled with water. Two important mechanisms: magneto-hydrodynamics and porous medium are also considered within the restricted domain of the fluid flow. Temperature is controlled with the wall temperature and then mathematical model is constructed in the form of PDEs. To determine the similarity solution results are obtained via two different techniques. Numerically solutions are obtained with the help of shooting technique and then validate with the help of optimal homotopy analysis method (OHAM). Obtained analytical and numerical results are validated graphically. Effect of emerging parameters are plotted for velocity and temperature profiles. It is found that for mixed convection parameter velocity profile depicts the increasing behavior for various values of power index m. However, for velocity profile shows the decreasing behavior with respect the parameter m. Temperature distribution in the restricted domain depicts the decreasing behavior for both m and . 相似文献
35.
Philippe Stempflé Toufik Djilali Richard Kouitat Njiwa Marthe Rousseau Evelyne Lopez Xavier Bourrat 《Tribology Letters》2009,35(2):97-104
Sheet nacre is a natural biocomposite with a multiscale structure including a mineral phase of calcium carbonate (97 wt.%)
and two organic matrices (3 wt.%). The mineral phase is constituted by an arrangement of CaCO3 biocrystal nanograins (ca 40 nm in size) drowned in an “intracrystalline” organic matrix (4 nm thick) in order to form a
microsized flat organomineral aragonite platelet. These platelets are themselves surrounded by an “intercrystalline” organic
matrix (40 nm thick) building up a very tough materials. This microarchitecture referred to as “bricks and mortar” nacre structure,
is mainly studied for the creation of new organic/inorganic hybrid materials. Currently, only little is known about the nacre
mechanical behaviour under dynamical loading and more particularly under tribological conditions which involve shocks and
thermal effects simultaneously. This paper brings out the thermal-induced damage mechanisms effect on the wear of sheet nacre
by the assessment of the thermal component of the friction with a scanning thermal microscope. Results reveal that the mean
contact pressure is the main driving force involved in the degradation of the organic constituents. For the lowest mean contact
pressure (<0.4 MPa), wear is rather weak because the friction-induced thermal component is not sufficient for degrading the
organic matrices. In contrast, beyond 0.4 MPa, the friction-induced contact temperature rises up over the melting point of
the organic matrices, and may even reach the temperature of the aragonite–calcite phase transformation increasing dramatically
the wear of sheet nacre. 相似文献
36.
This study reveals that the nanosilica hydrosols with higher specific surface areas had faster pozzolanic reactivity, especially at early ages; moreover, the results are indicative of the accelerating influence of nanosilicas and silica fume on the hydration of cement. Faster initial and final setting times observed for cement pastes containing nanosilicas are consequence of these mechanisms. However, less hydration degree of cement compared to the plain paste was observed at age of 7 days and after. This can be attributed to the entrapment of some of mix water in the aggregates of nanosilicas formed in cement paste environment, making less water available for the progress of cement hydration. The same mechanism is believed to be responsible for the reduction of flowability of cement pastes. 相似文献
37.
In the present investigation, at first, the surface of zinc oxide (ZnO) nanoparticles was treated with a silane coupling agent
of γ-methacryloxypropyltrimethoxy silane (KH570), which introduces organic functional groups on the surface of ZnO nanoparticles.
Secondly, optically active poly(amide–imide) (PAI) was synthesized via solution polycondensation of N,N′-(pyromellitoyl)-bis-phenylalanine diacid chloride 1 (M-1) with 4,4′-diaminodiphenylsulfone 2 (M-2). The polycondensation of diacid chloride with aromatic diamine was carried out with N,N-dimethylacetamide/triethylamine systems. Finally PAI/ZnO nanocomposites (NCs) containing 4, 8, and 12% of nanoparticles were
successfully fabricated through ultrasonic irradiation technique. The obtained NCs were characterized by Fourier transform-infrared
(FT-IR) spectroscopy, thermogravimetry analysis, X-ray powder diffraction, UV–Vis spectroscopy, scanning electron microscopy
(SEM), field emission-scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The FT-IR spectroscopy
indicated that the silane coupling agent was anchored on the surface of ZnO nanoparticles. SEM, FE-SEM, and TEM images were
showed ZnO nanoparticles were dispersed homogeneously in PAI matrix. 相似文献
38.
Hashem Asgharnejad Ehsan Khorshidi Nazloo Maryam Madani Larijani Nima Hajinajaf Hamidreza Rashidi 《Comprehensive Reviews in Food Science and Food Safety》2021,20(5):4779-4815
Food processing is among the greatest water-consuming industries with a significant role in the implementation of sustainable development goals. Water-consuming industries such as food processing have become a threat to limited freshwater resources, and numerous attempts are being carried out in order to develop and apply novel approaches for water management in these industries. Studies have shown the positive impact of the new methods of process integration (e.g., water pinch, mathematical optimization, etc.) in maximizing water reuse and recycle. Applying these methods in food processing industries not only significantly supported water consumption minimization but also contributed to environmental protection by reducing wastewater generation. The methods can also increase the productivity of these industries and direct them to sustainable production. This interconnection led to a new subcategory in nexus studies known as water-food-environment nexus. The nexus assures sustainable food production with minimum freshwater consumption and minimizes the environmental destructions caused by untreated wastewater discharge. The aim of this study was to provide a thorough review of water-food-environment nexus application in food processing industries and explore the nexus from different aspects. The current study explored the process of food industries in different sectors regarding water consumption and wastewater generation, both qualitatively and quantitatively. The most recent wastewater treatment methods carried out in different food processing sectors were also reviewed. This review provided a comprehensive literature for choosing the optimum scenario of water and wastewater management in food processing industries. 相似文献
39.
M. Madani 《Bulletin of Materials Science》2010,33(1):65-73
Methyl methacrylate (MMA) monomer was grafted onto low density polyethylene by the direct method of radiation grafting. The
effect of cohesive energy density of different organic solvents on the degree of grafting was investigated. It was found that
the extent of grafting depends largely on the kind of solvent, in which the highest degree of grafting was achieved in the
presence of dioxane, whereas the lowest degree of grafting occurred in the presence of methanol. This behaviour was attributed
to the solubility parameters of the solvent, monomer and polymer. The change in structure of the LDPE graft copolymer films
was characterized by scanning electron microscopy, X-ray diffraction, UV/vis absorption and thermogravimetric analysis. The
X-ray diffraction results showed a decrease in the crystallinity of LDPE graft copolymer matrix at high degree of grafting.
Studies were made on the UV-absorption edge, and indirect allowed transitions with their optical energy gaps are determined.
At the same time the Urbach energy was evaluated. The activation energy of the thermal decomposition was calculated according
to Horowitz and Metzger method. 相似文献
40.
Minh Tam Hoang Amandeep Singh Pannu Yang Yang Sepideh Madani Paul Shaw Prashant Sonar Tuquabo Tesfamichael Hongxia Wang 《纳微快报(英文)》2022,(4):277-288
The remarkable evolution of metal halide perovskites in the past dec-ade makes them promise for next-generation optoelectronic material.In particular,nanocrysta... 相似文献