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81.
We show how to construct semi-invariants and integrals of the full symmetric \({\mathfrak{sl}_n}\) Toda lattice for all n. Using the Toda equations for the Lax eigenvector matrix we prove the existence of semi-invariants which are homogeneous coordinates in the corresponding projective spaces. Then we use these semi-invariants to construct the integrals. The existence of additional integrals which constitute a full set of independent non-involutive integrals was known but the chopping and Kostant procedures have crucial computational complexities already for low-rank Lax matrices and are practically not applicable for higher ranks. Our new approach solves this problem and results in simple explicit formulae for the full set of independent semi-invariants and integrals expressed in terms of the Lax matrix and its eigenvectors, and of eigenvalue matrices for the full symmetric \({\mathfrak{sl}_n}\) Toda lattice. 相似文献
82.
Y Miao H Qin R Fu M Sharma TV Can I Hung S Luca PL Gor'kov WW Brey TA Cross 《Angewandte Chemie (International ed. in English)》2012,51(33):8383-8386
Validation: Membrane protein structures are sensitive to the environment used for structural characterization. NMR spectra of the full-length M2 proton channel from influenza?A were measured directly in E.?coli membranes and compared to spectra of the protein in synthetic lipid bilayers. The results demonstrate that these bilayers provide a native-like membrane environment. 相似文献
83.
K. A. Bugaev A. I. Ivanytskyi E. G. Nikonov V. K. Petrov A. S. Sorin G. M. Zinovjev 《Physics of Atomic Nuclei》2012,75(6):707-709
We discuss some ideas resulting from a phenomenological relation recently declared between the tension of string connecting the static quark-antiquark pair and surface tension of corresponding cylindrical bag. This relation analysis leads to the temperature of vanishing surface tension coefficient of the QGP bags at zero baryonic charge density as T ?? = 152.9 ± 4.5 MeV. We develop the view point that this temperature value is not a fortuitous coincidence with the temperature of (partial) chiral symmetry restoration as seen in the lattice QCD simulations. Besides, we argue that T ?? defines the QCD (tri)critical endpoint temperature and claim that a negative value of surface tension coefficient recently discovered is not a sole result but is quite familiar for ordinary liquids at the supercritical temperatures. 相似文献
84.
T Blochowicz S Schramm S Lusceac M Vogel B Stühn P Gutfreund B Frick 《Physical review letters》2012,109(3):035702
We study dynamically highly asymmetric binary mixtures comprised of small methyl tetrahydrofuran (MTHF) molecules and polystyrene. Combined use of dielectric spectroscopy, ^{2}H nuclear magnetic resonance, incoherent quasielastic neutron scattering, and depolarized dynamic light scattering allows us to selectively probe the dynamics of the components in a broad dynamic range. It turns out that the mixtures exhibit two glass transitions in a wide concentration range although being fully miscible on a macroscopic scale. In between both glass transition temperatures, the dynamics of the small molecules show strong confinement effects, e.g., a crossover from Vogel-Fulcher to Arrhenius behavior of the time constants. Moreover, the dynamical behavior of small molecules close to the slow matrix is consistent with mode coupling theory predictions for a type-A glass transition, which was expected from recent theoretical and simulation studies in comparable systems. 相似文献
85.
Stereoselective functionalization of pyrrolidinone moiety towards the synthesis of salinosporamide A
Julien Barbion Geoffroy Sorin Mohamed Selkti Esther Kellenberger Rachid Baati Stefano Santoro Fahmi Himo Ange Pancrazi Marie-Isabelle Lannou Janick Ardisson 《Tetrahedron》2012,68(32):6504-6512
An important feature of the synthesis of salinosporamide A, a potent proteasome inhibitor, is the establishment of the quaternary stereocenter at C3. A new route has been developed based on the methylation of a functionalized pyrrolidinone. Direct methylation reaction led to the unwanted diastereomer; however, by means of a Corey–Chaykovsky reaction followed by LiAlH4 epoxide opening, the desired alcohol was obtained. The pyrrolidinone was elaborated through a key allylation reaction between a tertiary allyltitanium reagent and an aldehyde bearing a spiroketal moiety in α-position. 相似文献
86.
Anicuta Stoica-Guzun Marta Stroescu Iuliana Jipa Loredana Dobre Sorin Jinga Traian Zaharescu 《Macromolecular Symposia》2012,315(1):198-204
The development of biodegradable packaging materials, especially from renewable resources is a constant preoccupation of nowadays, because of the environmental problems caused by synthetic polymers. The combination of cellulose with other polymeric materials could be an ecologic alternative and a way to use renewable resources for food packaging. Bacterial cellulose which is produced by microbial fermentation is also a promising material which can be used not only in biomedical application, but also as food packaging material. In this research different composite films between poly(vinyl alcohol)-bacterial cellulose (PVA-BC) were obtained by casting method. The obtained films were UV irradiated for different periods of times from 1 to 10 hours, using a mercury lamp, Philips TUV-30, emitting light mainly at 254 nm. Changes in FT-IR spectra before and after UV irradiation and the modification of transparency and of the swelling characteristics of the films were observed. As it was expected the composites materials are sensitive at UV exposure. 相似文献
87.
Sorin G. Gal 《Results in Mathematics》2012,61(3-4):347-353
In this paper we obtain the differentiated generalized Voronovskaja’s theorem in complex setting with upper and exact quantitative estimates. The results extend that obtained in the real case on [0, 1] in Gonska and Ra?a (Mat Vesnik 61:53–60, 2009) and generalize those obtained in the complex case in Gal (Results Math 53:257–268, 2009). 相似文献
88.
89.
In the frame of industrial risk and propulsive application, the detonability study of JP10–air mixtures was performed. The
simulation and measurements of detonation parameters were performed for THDCPD-exo/air mixtures at various initial pressure
(1 bar < P
0 < 3 bar) and equivalence ratio (0.8 < Φ < 1.6) in a heated tube (T
0 ~ 375 K). Numerical simulations of the detonation were performed with the STANJAN code and a detailed kinetic scheme of the
combustion of THDCPD. The experimental study deals with the measurements of detonation velocity and cell size λ. The measured
velocity is in a good agreement with the calculated theoretical values. The cell size measurements show a minimum value for
Φ ~ 1.2 at every level of initial pressure studied and the calculated induction length L
i corresponds to cell size value with a coefficient k = λ/L
i = 24 at P
0 = 1 bar. Based on the comparison between the results obtained during this study and those available in the literature on
the critical initiation energy E
c, critical tube diameter d
c and deflagration to detonation transition length L
DDT, we can conclude that the detonability of THDCPD–air mixtures corresponds to that of hydrocarbon–air mixtures.
This paper is based on the work presented at the 33rd International Pyrotechnics Seminar, IPS 2006, Fort Collins, July 16–21, 2006. 相似文献
This paper is based on the work presented at the 33rd International Pyrotechnics Seminar, IPS 2006, Fort Collins, July 16–21, 2006. 相似文献
90.
We prove that a sum of free non-covariant duality-symmetric actions does not allow consistent, continuous and local self-interactions that deform the gauge transformations. For instance, non-abelian deformations are not allowed, even in 4 dimensions where Yang–Mills type interactions of 1-forms are allowed in the non-manifestly duality-symmetric formulation. This suggests that non-abelian duality should require to leave the standard formalism of perturbative local field theories. The analyticity of self-interactions for a single duality-symmetric gauge field in four dimensions is also analyzed. 相似文献