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521.
522.
Angelo Marcello Tarantino Andrea Nobili 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2007,92(3):659-678
The equilibrium problem of nonlinear, isotropic and hyperelastic square membranes, stretched by a double symmetric system
of dead loads, is investigated. Depending on the form of the stored energy function, the problem considered may admit asymmetric
solutions in addition to the expected symmetric solutions. For compressible materials, the mathematical condition allowing
the computation of these asymmetric solutions is given. Moreover, explicit expressions for evaluating critical loads and bifurcation
points are derived. Results and basic relations obtained for general isotropic materials are then specialized for a compressible
Mooney–Rivlin material and a broad numerical analysis is performed. The qualitatively more interesting branches of asymmetric
equilibrium are shown and the influence of the material parameters is discussed. Finally, using the energy criterion, some
stability considerations are made. 相似文献
523.
John Tomkinson Mauro Bacci Marcello Picollo Daniele Colognesi 《Vibrational Spectroscopy》2009,50(2):268-276
We report the neutron vibrational spectra of indigo and its model compounds thioindigo and isatin. The neutron data extend the low energy range of the vibrational spectra of these molecules. The assignments, made with the help of ab-initio calculations, give convincing fits between the observed and scaled calculated results, and correct errors in the published literature. The indigo eigenvectors are described in terms of those of its model compound isatin. Finally, candidate modes, that could be used to study indigoids in matices (e.g. ‘Maya Blue’), are selected. 相似文献
524.
S. Abd El-Samad R. Bilger K. -Th. Brinkmann H. Clement M. Dietrich E. Doroshkevich S. Dshemuchadse K. Ehrhardt A. Erhardt W. Eyrich A. Filippi H. Freiesleben M. Fritsch R. Geyer A. Gillitzer J. Hauffe D. Hesselbarth R. Jaekel B. Jakob L. Karsch K. Kilian J. Kress E. Kuhlmann S. Marcello S. Marwinski R. Meier K. M?ller H. P. Morsch L. Naumann J. Ritman E. Roderburg P. Sch?nmeier M. Schulte-Wissermann W. Schroeder F. Stinzing G. Y. Sun J. W?chter G. J. Wagner M. Wagner U. Weidlich A. Wilms S. Wirth G. Zhang P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2009,42(2):159-161
Data accumulated recently for the exclusive measurement of the pp $ \rightarrow$ pp $ \pi^{+}_{}$ $ \pi^{-}_{}$ reaction at a beam energy of 0.793GeV using the COSY-TOF spectrometer have been analyzed with respect to possible events from the pp $ \rightarrow$ nn $ \pi^{+}_{}$ $ \pi^{+}_{}$ reaction channel. The latter is expected to be the only $ \pi$ $ \pi$ production channel, which contains no major contributions from resonance excitation close to threshold and hence should be a good testing ground for chiral dynamics in the $ \pi$ $ \pi$ production process. No single event has been found, which meets all conditions for being a candidate for the pp $ \rightarrow$ nn $ \pi^{+}_{}$ $ \pi^{+}_{}$ reaction. This gives an upper limit for the cross-section of 0.16μb (90% C.L.), which is more than an order of magnitude smaller than the cross-sections of the other two-pion production channels at the same incident energy. 相似文献
525.
为了描述对称空间中的无规运动,建立了群流形中的扩散方程,给出了紧致黎曼空间中扩散方程的一种具体形式,并进一步讨论了紧致黎曼空间中量子扩散运动. 相似文献
526.
Isabella Camurati Giuseppe Gioia Fabrizio Piemontesi Stefano Tartarini Alessandra Bonazza Annamaria Farotti Marcello Colonnesi 《Macromolecular Symposia》2009,282(1):101-110
Summary: The aim of this work was to study the comonomer distribution and the chemical composition distribution generated by different Ziegler-Natta (ZN) systems (different internal donors, ID, dicyclopentadienyl-dimethoxy silane, D donor, as the external donor) and to define the potentialities of different IDs to produce improved heterophasic copolymers (HECO). A methodology to quantify the amount of ethylene-propylene copolymer (EP) portion in ZN-HECO and ethylene content of the EP portion by 13C-NMR was established. By using this method, it was possible to analyze the composition of ZN-HECO obtaining results comparable to those obtained with a more complex fractionation technique. 相似文献
527.
Andre H. St.Amant Fengying Huang Jia Lin Keith Rickert Vaheh Oganesyan Daniel Lemen Shenlan Mao Jay Harper Marcello Marelli Herren Wu Changshou Gao Javier ReaddeAlaniz R. James Christie 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(25):8577-8581
Here, we describe a diene‐containing noncanonical amino acid (ncAA) capable of undergoing fast and selective normal electron‐demand Diels–Alder (DA) reactions following its incorporation into antibodies. A cyclopentadiene derivative of lysine (CpHK) served as the reactive handle for DA transformations and the substrate for genetic incorporation. CpHK incorporated into antibodies with high efficiency and was available for maleimide conjugation or self‐reaction depending on position in the amino acid sequence. CpHK at position K274 reacted with the maleimide drug‐linker AZ1508 at a rate of ≈79 m ?1 s?1 to produce functional antibody–drug conjugates (ADCs) in a one‐step process. Incorporation of CpHK at position S239 resulted in dimerization, which covalently linked antibody heavy chains together. The diene ncAA described here is capable of producing therapeutic protein conjugates with clinically validated and widely available maleimide compounds, while also enabling proximity‐based stapling through a DA dimerization reaction. 相似文献
528.
Giovanna Guidoboni Marcello Guidorzi Mariarosaria Padula 《Journal of Mathematical Fluid Mechanics》2012,14(1):1-32
We prove a continuous dependence theorem for weak solutions of equations governing a fluid–structure interaction problem in
two spatial dimensions. The proof is based on a priori estimates which, in particular, convey uniqueness of weak solutions. The estimates are obtained using Eulerian coordinates,
without remapping the problem into a fixed domain. 相似文献
529.
Numerical calculation of FSS/RSS transition in highly overexpanded rocket nozzle flows 总被引:1,自引:0,他引:1
Turbulent flow separation in over-expanded rocket nozzles is investigated numerically in a sub-scale parabolic nozzle fed
with cold nitrogen. Depending upon the feeding to ambient pressure ratio either a free shock separation or a restricted shock
separation is computed, with a significant hysteresis between these two flow regimes. This hysteresis was also found in experimental
tests with the same nozzle geometry. The present study is mainly focused on the transition between the two shock separation
patterns. The analysis of the numerical solutions aims to provide clues for the explanation of the hysteresis cycle. 相似文献
530.
Campione M Sassella A Moret M Papagni A Trabattoni S Resel R Lengyel O Marcon V Raos G 《Journal of the American Chemical Society》2006,128(41):13378-13387
Hot-wall epitaxy and molecular-beam epitaxy have been employed for growing quaterthiophene thin films on the (010) cleavage face of potassium hydrogen phthalate, and the results are compared in terms of film properties and growth mode. Even if there is no geometrical match between substrate and overlayer lattices, these films are epitaxially oriented. To investigate the physical rationale for this strong orientation effect, optical microscopy, atomic force microscopy, and X-ray diffraction are employed. A clear correlation between the morphology of the thin films and the crystallographic orientation is found. The results are also validated by surface potential calculations, which demonstrate the primary role played by the corrugation of the substrate surface. 相似文献