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121.
Abdelkader Merakeb Frédéric Messine Mohamed Aidène 《4OR: A Quarterly Journal of Operations Research》2014,12(3):261-283
The problem we address in this paper, is the minimization of the energy consumption of an electrical vehicle achievable on a given driving cycle. This can be formulated as an optimal control problem with a discrete switch control. In this paper, we present a new formulation of this problem by taking into account the electrical and mechanical parts of the vehicle. By using prototype optimal control shooting techniques, we did not provide efficient solutions. Consequently, we focused on an operational method based on a Branch and Bound algorithm to solve this optimal switching control problem. Some numerical experiments validate our methodology. 相似文献
122.
Zahraoui Mehdi Mokhtar Adel Adjdir Mehdi Bennabi Farid Khaled Rahmani Djelad Amal Bengueddach Abdelkader Sassi Mohamed 《Research on Chemical Intermediates》2019,45(2):633-644
Research on Chemical Intermediates - In this work, the Al-magadiite is synthesized by the hydrothermal method. It is then used to prepare three copper exchanged materials using copper nitrate,... 相似文献
123.
Dr. Arina Dalaloyan Dr. Andrea Martorana Dr. Yoav Barak Diana Gataulin Prof. Eitan Reuveny Dr. Andrew Howe Prof. Michael Elbaum Dr. Shira Albeck Dr. Tamar Unger Dr. Veronica Frydman Dr. Elwy H. Abdelkader Prof. Gottfried Otting Prof. Daniella Goldfarb 《Chemphyschem》2019,20(14):1860-1868
It is an open question whether the conformations of proteins sampled in dilute solutions are the same as in the cellular environment. Here we address this question by double electron-electron resonance (DEER) distance measurements with Gd(III) spin labels to probe the conformations of calmodulin (CaM) in vitro, in cell extract, and in human HeLa cells. Using the CaM mutants N53C/T110C and T34C/T117C labeled with maleimide-DOTA-Gd(III) in the N- and C-terminal domains, we observed broad and varied interdomain distance distributions. The in vitro distance distributions of apo-CaM and holo-CaM in the presence and absence of the IQ target peptide can be described by combinations of closed, open, and collapsed conformations. In cell extract, apo- and holo-CaM bind to target proteins in a similar way as apo- and holo-CaM bind to IQ peptide in vitro. In HeLa cells, however, in the presence or absence of elevated in-cell Ca2+ levels CaM unexpectedly produced more open conformations and very broad distance distributions indicative of many different interactions with in-cell components. These results show-case the importance of in-cell analyses of protein structures. 相似文献
124.
Ricerche di Matematica - The problem of Moore–Gibson–Thompson equation with infinite memory and time delay terms is considered. Under suitable Lyapunov functionals with an appropriate... 相似文献
125.
Adel Mokhtar Zohra Aouali Kebir Medjhouda Amal Djelad Abdelkader Boudia Abdelkader Bengueddach Mohamed Sassi 《Chemical Papers》2018,72(1):39-50
In this work, the ion-exchange reaction of the sodium silicate Na-magadiite with cupric ions was studied and the mode of interaction of the intercalated Cu2+ ions with silicate sheet was investigated. To do this, Na-magadiite was first synthesized using a hydrothermal method and characterized. It is then used to prepare Cu-exchanged magadiite materials with different copper contents by an ion-exchange reaction. The solids obtained were characterized by chemical and thermogravimetric analyses, powder X-ray diffraction, UV–Visible diffuse reflectance and Fourier transform spectroscopy, scanning electron microscopy and transmission electron microscopy. The results show that magadiite has a high affinity to copper ions and that the experimental exchange rate can be easily predicted. They show also that the intercalated Cu2+ ions are non-hydrated and are in direct interactions with the terminal interlayer ≡Si–O? groups, to which they are also probably strongly linked. Furthermore, the interlayer copper oxide species phase formed are in form of small particles homogeneously dispersed. Finally, the introduction of Cu2+ ions into the interlayer space does not substantially affect the structure of the Cu-exchanged materials but rather tends to stabilize it by increasing the decomposition temperature of the silanol groups . 相似文献
126.
In this paper we investigate the existence of positive solutions of nonlocal second-order boundary value problems with integral boundary conditions. 相似文献
127.
A two-dimensional dynamic fouling model for milk fouling in a plate heat exchanger (PHE) is proposed. Emphasis is placed on fouling prediction based on the hydrodynamic and thermodynamic performances of the PHE. A 12-channel PHE with counter-current flows is used in quantification of the milk deposition developed inside the channels. The aggregation rate of unfolded protein is found to increase exponentially with increasing wall temperature and is accompanied by a substantial reduction in the heat-transfer coefficient. 相似文献
128.
Structural and electron charge density studies of a nonlinear optical compound 4,4 di-methyl amino cyano biphenyl
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The 4,4 dimethyl amino cyano biphenyl crystal(DMACB) is characterized by its nonlinear activity. The intra molecular charge transfer of this molecule results mainly from the electronic transmission of the electro-acceptor(cyano) and electro-donor(di-methyl-amino) groups. An accurate electron density distribution around the molecule has been calculated based on a high-resolution X-ray diffraction study. The data were collected at 123 K using graphite-monochromated Mo Kα radiation to sin(θ)/λ = 1.24 A 1. The integrated intensities of 13796 reflections were measured and reduced to 6501 independent reflections with I ≥ 3σ(I). The crystal structure was refined using the experimental model of Hansen and Coppens(1978). The crystal structure has been validated and deposited at the Cambridge Crystallographic Data Centre with the deposition number CCDC 876507. In this article, we present the thermal motion and the structural analysis obtained from the least-square refinement based on F2 and the electron density distribution obtained from the multipolar model. 相似文献
129.
In this paper we give some congruences on the r-derangement polynomials (defined below), Lah polynomials and some versions of Bell numbers and polynomials. 相似文献
130.
Abderrahmane Bendali Alain Huard Abdelkader Tizaoui Sébastien Tordeux Jean-Paul Vila 《Comptes Rendus Mathematique》2009,347(19-20):1147-1152
This Note presents the derivation of the 2nd-order asymptotic expansion of the eigenvalues and the eigenfunctions of the operator associated to an interior elliptic equation supplemented by a Dirichlet boundary condition on a domain consisting of two cavities linked by a hole of small size. The asymptotic expansion is carried out with respect to the size of the hole. The main feature of the method is to yield a robust numerical procedure making it possible to compute the eigenvalues without resorting to a refined mesh around the hole. To cite this article: A. Bendali et al., C. R. Acad. Sci. Paris, Ser. I 347 (2009). 相似文献