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231.
M Benabdeslem A Bouasla N Benslim L Bechiri S Mehdaoui O Aissaoui A Djekoun M Fromm X Portier 《Bulletin of Materials Science》2014,37(3):469-472
Incorporation of the doping element Zn in the temperature range (550–700 °C) and the impact on structural and electrical properties of CuInSe2 material are investigated. X-ray diffraction patterns showed the chalcopyrite nature of the pure and doped CuInSe2 and revealed that diffusion temperature governs particle size as well as tensile strain. The calculated lattice parameters and cell volumes revealed that Zn diffuses in CuInSe2 by substitution on Cu sites. Electrical properties of the material have been investigated using a contact-less technique based on high frequency microwave (HF). It is found that Zn atoms influence the defect equilibrium resulting in the conversion of the conduction type. The conductivity of the samples has been found increasing as the diffusion temperature increases. 相似文献
232.
Structure–Activity Relationship,Biological, and Pharmacological Characterization of the Proline Sulfonamide ACT‐462206: a Potent,Brain‐Penetrant Dual Orexin 1/Orexin 2 Receptor Antagonist
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Dr. Christoph Boss Dr. Catherine Roch‐Brisbare Dr. Michel A. Steiner Dr. Alexander Treiber Dr. Hendrik Dietrich Dr. Francois Jenck Dr. Markus von Raumer Dr. Thierry Sifferlen Dr. Christine Brotschi Dr. Bibia Heidmann Dr. Jodi T. Williams Dr. Hamed Aissaoui Dr. Romain Siegrist Dr. John Gatfield 《ChemMedChem》2014,9(11):2486-2496
The orexin system consists of two G‐protein‐coupled receptors, the orexin 1 and orexin 2 receptors, widely expressed in diverse regions of the brain, and two peptide agonists, orexin A and orexin B, which are produced in a small assembly of neurons in the lateral hypothalamus. The orexin system plays an important role in the maintenance of wakefulness. Several compounds (almorexant, SB‐649868, suvorexant) have been in advanced clinical trials for treating primary insomnia. ACT‐462206 is a new, potent, and selective dual orexin receptor antagonist (DORA) that inhibits the stimulating effects of the orexin peptides at both the orexin 1 and 2 receptors. It decreases wakefulness and increases non‐rapid eye movement (non‐REM) and REM sleep while maintaining natural sleep architectures in rat and dog electroencephalography/electromyography (EEG/EMG) experiments. ACT‐462206 shows anxiolytic‐like properties in rats without affecting cognition and motor function. It is therefore a potential candidate for the treatment of insomnia. 相似文献
233.
In steel-concrete composite beams, the shear connectors are commonly used to transfer the longitudinal shear forces across the steel-concrete interface. This paper summarizes the results of 24 push-out test specimens with a new type of shear connector called “I-shape connector”. The test specimens were designed to study the effect of the following parameters on the ultimate load capacity: the height of I-shape connector, the length of I-shape connector, the compressive strength of concrete and the number of transverse reinforcing bars. The experimental results are presented and discussed, focusing on the failure modes and load-slip behaviour. Finally, the experimental results are compared to the existing design equations to predict the ultimate load capacity of I-shape shear connectors. 相似文献
234.
D. Abdelkader N. Khemiri M. Kanzari 《Materials Science in Semiconductor Processing》2013,16(6):1997-2004
In this study, the annealing effect on structural, electrical and optical properties of CuIn2n+1S3n+2 thin films (n=0, 1, 2 and 3) are investigated. CuIn2n+1S3n+2 films were elaborated by vacuum thermal evaporation and annealed at 150 and 250 °C during 2 h in air atmosphere. XRD data analysis shows that CuInS2 and CuIn3S5 (n=0 and 1) crystallize in the chalcopyrite structure according to a preferential direction (112), CuIn5S8 and CuIn7S11 (n=2 and 3) crystallize in the cubic spinel structure with a preferential direction (311). The optical characterization allowed us to determine the optical constants (refractive indexes 2.2–3.1, optical thicknesses 250–500 nm, coefficients of absorption 105 cm?1, coefficients of extinction <1, and the values of the optical transitions 1.80–2.22 eV) of the samples of all materials. We exploited the models of Cauchy, Wemple–DiDomenico and Spitzer–Fan for the analysis of the dispersion of the refractive index and the determination of the optical and dielectric constants. 相似文献
235.
Abdelkader Boukhobza Abdennacer Bounoua Abdelmalik Taleb-Ahmed Nasreddine Taleb 《Circuits, Systems, and Signal Processing》2013,32(4):1725-1744
In this paper, we present an optimization method based on a multi-objective Genetic Algorithm (GA) for the design of linear phase filter banks for an image coding scheme. To be effective, the filter banks should satisfy a number of desirable criteria related to such a scheme. Instead of imposing the entire PR condition as in conventional designs, we introduce flexibility in the design by relaxing the Perfect Reconstruction (PR) condition and defining a PR violation measure as an objective criterion to maintain near perfect reconstruction (N-PR) filter banks. Particularly in this work, the designed filter banks are near-orthogonal. This has been made possible by minimizing the deviation from the orthogonality in the optimization process. The optimization problem is formulated as a constrained multi-objective, and a modified Nondominated Sorting Genetic Algorithm NSGAII is proposed in this work to find the Pareto optimal solutions that achieve the best compromise between the different objective criteria. The experimental results show that the filter banks designed with the proposed method outperform significantly the 9/7 filter bank of JPEG2000 in most cases. Furthermore, the filter banks are near orthogonal. This is very helpful, especially where embedded coding is required. 相似文献
236.
A. Abdelkader H. Daly Y. Saih K. Morgan M.A. Mohamed S.A. Halawy C. Hardacre 《International Journal of Hydrogen Energy》2013
Co3O4, Fe2O3 and a mixture of the two oxides Co–Fe (molar ratio of Co3O4/Fe2O3 = 0.67 and atomic ratio of Co/Fe = 1) were prepared by the calcination of cobalt oxalate and/or iron oxalate salts at 500 °C for 2 h in static air using water as a solvent/dispersing agent. The catalysts were studied in the steam reforming of ethanol to investigate the effect of the partial substitution of Co3O4 with Fe2O3 on the catalytic behaviour. The reforming activity over Fe2O3, while initially high, underwent fast deactivation. In comparison, over the Co–Fe catalyst both the H2 yield and stability were higher than that found over the pure Co3O4 or Fe2O3 catalysts. DRIFTS-MS studies under the reaction feed highlighted that the Co–Fe catalyst had increased amounts of adsorbed OH/water; similar to Fe2O3. Increasing the amount of reactive species (water/OH species) adsorbed on the Co–Fe catalyst surface is proposed to facilitate the steam reforming reaction rather than decomposition reactions reducing by-product formation and providing a higher H2 yield. 相似文献
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239.
With globalization and the emergence of the extended enterprise of interdependent organizations, there has been a steady increase in the outsourcing of parts and services. This has led firms to give more importance to the purchasing function and its associated decisions. One of those decisions which impacts all firms’ areas is the supplier selection. Since the 1950s, several works have addressed this decision by treating different aspects and instances. In this paper, we extend previous survey papers by presenting a literature review that covers the entire purchasing process, considers both parts and services outsourcing activities, and covers internet-based procurement environments such as electronic marketplaces auctions. In view of its complexity, we will focus especially on the final selection stage that consists of determining the best mixture of vendors and allocating orders among them so as to satisfy different purchasing requirements. In addition, we will concentrate mainly on works that employ operations research and computational models. Thereby, we will analyze and expose the main decision's features, and propose different classifications of the published models. 相似文献
240.
Cancer is one of the most widespread diseases in the world. Researchers thought of carrying out systems that will be the assistance tools for the decision and diagnosis to the doctors. The setting on network of such systems permits to have an application of tele-diagnosis, the goal is to bring « a second opinion » by a distant specialist to validate or invalidate the diagnosis established by the local expert, or to help this latter in making a correct diagnosis. To design such systems, several aspects are to dealt with. One of the most significant aspects is the problem of the big size of the medical images compared to the transmission flow. For that, in the case of the cerebral cancer, we propose to design a stage for extracting the lesions, its role is extracting the lesion with the respect of its size, its shape and its position. Since, the size of images to be sent decreases, because they are in two grey levels (black and white). The second goal of this stage is to simplify the image for the doctor with preserve all morphological characteristics of the lesions. For that, we can proceed by two manners, by extracting the edges of the lesion, or extracted all its areas. We use algorithms based on mathematical morphology operators, promising results were obtained, that permits to the doctor to begin the diagnosis step in a sure manner in local or distant areas. In this paper, we present mainly our tele-diagnosis system and the various algorithms used for designing the stage of lesion extraction. 相似文献