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21.
The characterization of virgin olive oils from six Tunisian cultivars, namely Chétoui, Ain Jarboua, Jarboui, Regregui, Rekhami and Neb Jmel, grown in Nebeur (a region of the Kef) was carried out. These cultivars dominate their natural habitats, but with the exception of the Chétoui cultivar they are only scattered throughout the nation. Several analytical parameters were evaluated; these include quality index, fatty acid composition, chlorophylls, carotenoids, sterols, α‐tocopherol and phenolic compounds. Their relationship with oxidative stability was also tested. The main phenols found were tyrosol, hydroxytyrosol, the dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol, oleuropein aglycon and pinoresinol. These phenolic compounds, the colorimetric total phenol content and o‐diphenols showed significant correlations with oxidative stability. Furthermore, most of the analytical parameters of the oils that were determined in this study were greatly influenced by genetic factors (cultivar).  相似文献   
22.
Three dinuclear coordination complexes generated from 1-n-butyl-2-((5-methyl-1H-pyrazole-3-yl)methyl)-1H-benzimidazole ( L ), have been synthesized and characterized spectroscopically and structurally by single crystal X-ray diffraction analysis. Reaction with iron(II) chloride and then copper(II) nitrate led to a co-crystal containing 78 % of [Cu(NO3)(μ-Cl)( L’ )]2 ( C1 ) and 22 % of [Cu(NO3)(μ-NO3)( L’ )]2 ( C2 ), where L was oxidized to a new ligand L . A mechanism is provided. Reaction with copper chloride led to the dinuclear complex [Cu(Cl)(μ-Cl)( L) ]2 ( C3 ). The presence of N−H⋅⋅⋅O and C−H⋅⋅⋅O intermolecular interactions in the crystal structure of C1 and C2 , and C−H⋅⋅⋅N and C−H⋅⋅⋅Cl hydrogen bonding in the crystal structure of C3 led to supramolecular structures that were confirmed by Hirshfeld surface analysis. The ligands and their complexes were tested for free radical scavenging activity and ferric reducing antioxidant power. The complex C1 / C2 shows remarkable antioxidant activities as compared to the ligand L and reference compounds.  相似文献   
23.
24.
Fibre Bragg grating compression-tuned over 110 nm   总被引:2,自引:0,他引:2  
A fibre Bragg grating with a tuning range covering beyond the C- and L-bands has been realised, which represents the broadest tuning range reported of any Bragg grating. The device exhibits constant spectral response and polarisation mode dispersion within these bands.  相似文献   
25.
Feldspar/titanium dioxide/chitosan hybrid, a photoactive biocompatible adsorbent for anionic dyes, was synthesized, characterized, and successfully tested. The adsorbent characterization, pH role, adsorbent dose effect, equilibrium data, kinetic plats, and thermodynamic parameters are reported. The point of zero charge for the hybrid was measured to be 8.3, and the most favorable pH range for the adsorption process was found to be below this pH value. The adsorption equilibrium study demonstrated that the Freundlich model was best fitted to the experimental data. Without UV light exposure, the prepared adsorbent adsorbed 72 mg of Acid Black 1 (AB1)/g of sorbent (86% removal) from a 100‐mL solution with an initial dye concentration of 50 mg/L, whereas UV irradiation resulted in an increase in the elimination of AB1 dye (97% removal). The kinetic data was depicted well by the pseudo‐second‐order model. The thermodynamic parameters indicated that the reaction between the hybrid and the dye was exothermic and also spontaneous at lower temperatures. In the batch desorption process, several aqueous solutions adjusted to different pH values were tested, and the best desorption performance (90% desorption) was achieved at pH 11. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40247.  相似文献   
26.
Illinois Institute of Technology started a bachelor of science degree program in architectural engineering in the fall of 1995. The program's curriculum requires the students to take 136 semester credit hours during a period of eight semesters, with the option for specialization in one of the three main areas of architectural engineering. To share the experience worldwide with schools that intend to offer similar bachelor degrees, this paper presents the architectural engineering curriculum at Illinois Institute of Technology. It discusses the objectives of the curriculum, the constraints upon its structure, as well as the challenges that face the establishment of an architectural engineering program.  相似文献   
27.
Journal of Inorganic and Organometallic Polymers and Materials - The discharge of industrial waste comprising organic pollutants into aquatic environment induces numerous health risks. Crosslinked...  相似文献   
28.
Active Fiber Bragg Grating Hydrogen Sensors for All-Temperature Operation   总被引:1,自引:0,他引:1  
The use of liquid hydrogen as a fuel requires low-cost multipoint sensing of hydrogen gas for leak detection and location well below the 4% explosion limit of hydrogen. Herein is presented a multipoint in-fiber hydrogen sensor capable of hydrogen detection below 0.5% concentration with a response time of less than 10 s. Our solution entails use of a fiber Bragg grating (FBG) coated with a layer of hydrogen-absorbing palladium which, in turn, induces strain in the FBG in the presence of hydrogen. Infrared power laser light is used to induce heating in the palladium coating which dramatically decreases sensor response time and increases the sensor's sensitivity at low temperatures. This technology promises an inexpensive fiber solution for a multipoint hydrogen detection array with only one fiber feed-through  相似文献   
29.
ABSTRACT

This paper deals with partial information stochastic optimal control problem for general controlled mean-field systems driven by Teugels martingales associated with some Lévy process having moments of all orders, and an independent Brownian motion. The coefficients of the system depend on the state of the solution process as well as of its probability law and the control variable. We establish a set of necessary conditions in the form of Pontryagin maximum principle for the optimal control. We also give additional conditions, under which the necessary optimality conditions turn out to be sufficient. The proof of our result is based on the derivative with respect to the probability law by applying Lions derivatives and a corresponding Itô formula. As an application, conditional mean-variance portfolio selection problem in incomplete market, where the system is governed by some Gamma process is studied to illustrate our theoretical results.  相似文献   
30.
Due to their advantages, facial recognition systems are among the most widely used biometric systems in recent years. However, their drawback is that they can easily be deceived by using 3D masks, which are replicas of real faces. To confirm this fact, we have tested the vulnerability to 3D masks attacks of the already approved Legendre moments invariants (LMI)-based face recognition method. This has been achieved by using the 3D mask attack database (3DMAD), which consists of real faces and faces with 3D masks. The obtained spoof false acceptance rate (SFAR) was close to 65%, which proves that this recognition system is vulnerable to 3D masks attacks. This is generally the case of other face recognition systems, with no anti-spoofing provision. In this paper, a face recognition method is proposed to prevent hackers from deceiving face recognition systems by using 3D masks of people belonging to the system database. This method combines the LMI and the linear discriminant analysis for characteristic features extraction, and the maximum likelihood for classification. With a 97.6% recognition rate and a SFAR equal to 0.83%, the results obtained may be considered as very satisfactory. These results, while obtained with a lower computational time, compare favorably with those of the state-of-the-art method that uses the same 3DMAD database.  相似文献   
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