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81.
Charles E. Starrett Romain Perriot Nathaniel R. Shaffer Tammie Nelson Lee A. Collins Chris Ticknor 《等离子体物理论文集》2020,60(3):e201900123
A new Sesame-type table for the electrical conductivity of aluminium is described. The table is based on density functional theory calculations and ranges from 10−3 to 1 times solid density (2.7 g/cm3), and from 10−2 to 103 eV in temperature. The table is compared with other those of simulations and to experiments and is generally in good agreement. The high-temperature, classical limit of the conductivity is recovered for the highest temperatures and lowest densities. The table is critically evaluated, and directions for improvements are discussed. 相似文献
82.
83.
Romain Lecaque Samuel Grésillon Nicolas Barbey Romain Peretti Jean-Claude Rivoal Claude Boccara 《Optics Communications》2006,262(1):125-128
A new THz imaging system based on a local illumination by a near-field source is presented. Model object is imaged, and sub-wavelength spatial resolution is demonstrated for the first time to our knowledge with this configuration. The contrast and the resolution are confirmed by a theoretical study based on the diffraction in near-field zone. 相似文献
84.
Emmanuel Moulay Romain Bourdais Wilfrid Perruquetti 《Nonlinear Analysis: Hybrid Systems》2007,1(4):482-490
In this paper, we study the stabilization of general nonlinear switched systems by using control Lyapunov functions. The concept of control Lyapunov function for nonlinear control systems is generalized to switched control systems. The first part of our contribution provides a necessary and sufficient condition of stabilization. The main idea is to use a common control Lyapunov function; this is achieved with the converse Lyapunov theorem dedicated to switched systems. In the second part, an explicit construction of a common control Lyapunov function is addressed with respect to a finite family of switched systems. The approach uses a family of control Lyapunov functions attached to the subsystems. 相似文献
85.
Jacques Dauxois Guy Martial Nkiet Yves Romain 《Annals of the Institute of Statistical Mathematics》2004,56(2):279-304
We introduce the Linear Relative Canonical Analysis (LRCA) of Euclidean random variables. Then similar properties than for
usual linear Canonical Analysis are obtained. Furthermore, we develop an asymptotic study of LRCA and apply the obtained results
to tests for lack of relative linear association, dimensionality and invariance. 相似文献
86.
Infrared and Raman spectra of the BaF(HF2) crystal and its 10 and 50% deuterated derivatives at 300 and 90 K have been investigated in the 4000 to 20 cm−1 range. An assignment of internal and lattice vibrations has been proposed. Vibrational spectra are consistent with a centrosymmetric P21/m space group and Z=2. They show that the (FHF)− ion is not centrosymmetrical, in spite of a short F…F distance; a force field calculation has been performed in order to determine the F---H and H…F distances, which are equal to 1.08 and 1.20 Å, respectively, in agreement with the 1H and 19F NMR data. The ν3(H)/ν3(D) isotope frequency ratio indicates a negative or zero isotope effect on the F…F distance, which is observed for the first time for a strong asymmetric hydrogen bond. 相似文献
87.
The Raman spectra of AlCl(3)-LiCl-dimethylsulfone mixtures with different molar compositions have been recorded as a solid (300 K) and as a melt (400 K). In any case, only AlCl(4)(-) ion lines at 120, 179, and 347 cm(-)(1) were observed; we were unable to detect any other chloroaluminate species. Furthermore, some bands assigned to the Al[(CH(3))(2)SO(2)](3)(3+) octahedral coordination compound are evidence for a high AlCl(3) content. 相似文献
88.
Romain Barbe 《Tetrahedron》2007,63(10):2199-2207
The design of a new biomimetic foldamer, relying on the weak amine-carbonyl interaction for secondary structure formation, is presented. The efficient synthesis of a triply protected monomer starting from glycidol was developed. This monomer contains a dioxolane-protected keto group that will allow liberation of the ketone functionality in the backbone once construction of the oligomeric backbone is complete. This monomer contains two additional orthogonal protecting groups at its two termini, the Fmoc and the TBDMS groups. The Fmoc group in particular permits oligomerisation towards the N terminus as seen in Fmoc solid phase peptide synthesis. Construction and full characterisation of a ketone-protected dimer, trimer and tetramer are reported. 相似文献
89.
A general synthetic strategy for the preparation of polyazamacrocycles containing long aliphatic chains is reported. These compounds are 22- or 24-membered hexaazamacrocycles incorporating two diethylenetriamine subunits (H2NCH2CH2NHCH2CH2NH2) linked together either by two CH2CH2OCH2CH2 (see 4–6 ), two tetramethylene (see 7 ), or two pentamethylene (see 8 ) fragments. Whereas for compound 4 , one of the centrally located amine functionalities of the triamine subunit bears a hexadecyl chain, for compound 5 , two of such chains are centrally attached to both subunits. In macrocycles 6–8 , all six amino functionalities bear hexadecyl chains. Compounds 4–8 are potential candidates for the construction of selective chemical sensors such as specific electrodes for adenosine mono-, di-, and tri-phosphate. They may also be used for nucleoside polyphosphates extraction and/or transport. 相似文献
90.
The retention behaviour of the three positional isomers of monosubstituted sulfobutyl ether-beta-cyclodextrin was investigated on a porous graphitic carbon (PGC) column. The influence of the mobile phase composition (nature and concentration of organic and electronic modifiers) was studied as well as the effect of column temperature. These hydrophilic and anionic analytes were highly retained on the PGC stationary phase compared to octadecyl bonded phases. The retention is mainly governed by a reversed-phase mechanism with electronic interaction playing a secondary role. An increase in solute retention and efficiency with temperature was observed. Successful isocratic separation with satisfactory baseline resolution of the three isomers of monosubstituted sulfobutyl ether-beta-cyclodextrin was achieved at 75 degrees C on a Hypercarb column by using ammonium acetate as electronic modifier in water-acetonitrile (83:17). The chromatographic methodology developed can be easily used for relative quantification of each isomer within a mixture and can be applied for semi-preparative purification of each one. The evaporative light scattering detector allows the detection of these non UV-visible absorbing molecules. 相似文献