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121.
Massimiliano Berti Riccardo Montalto 《Journal of Fixed Point Theory and Applications》2017,19(1):129-156
We present the result and the ideas of the recent paper (Berti and Montalto, Quasi-periodic standing wave solutions of gravity-capillary water waves, http://arxiv.org/abs/1602.02411, 2016) concerning the existence of Cantor families of small-amplitude time quasi-periodic standing wave solutions (i.e. periodic and even in the space variable x) of a 2-dimensional ocean, with infinite depth, in irrotational regime, under the action of gravity and surface tension at the free boundary. These quasi-periodic solutions are linearly stable. 相似文献
122.
This paper concerns reaction–diffusion systems consisting of three or four equations, which come out of reversible chemistry. We introduce different scalings for those systems, which make sense in various situations (species with very different concentrations or very different diffusion rates, chemical reactions with very different rates, etc.). We show how recently introduced mathematical tools allow to prove that the formal asymptotics associated to those scalings indeed hold at the rigorous level. 相似文献
123.
124.
Dietrich PM Horlacher T Girard-Lauriault PL Gross T Lippitz A Min H Wirth T Castelli R Seeberger PH Unger WE 《Langmuir : the ACS journal of surfaces and colloids》2011,27(8):4808-4815
Carbohydrate films on gold based on dimannoside thiols (DMT) were prepared, and a complementary surface chemical analysis was performed in detail by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), near-edge X-ray absorption fine structure (NEXAFS), FT-IR, and contact angle measurements in order to verify formation of ω-carbohydrate-functionalized alkylthiol films. XPS (C 1s, O 1s, and S 2p) reveals information on carbohydrate specific alkoxy (C-O) and acetal moieties (O-C-O) as well as thiolate species attached to gold. Angle-resolved synchrotron XPS was used for chemical speciation at ultimate surface sensitivity. Angle-resolved XPS analysis suggests the presence of an excess top layer composed of unbound sulfur components combined with alkyl moieties. Further support for DMT attachment on Au is given by ToF-SIMS and FT-IR analysis. Carbon and oxygen K-edge NEXAFS spectra were interpreted by applying the building block model supported by comparison to data of 1-undecanethiol, poly(vinyl alcohol), and polyoxymethylene. No linear dichroism effect was observed in the angle-resolved C K-edge NEXAFS. 相似文献
125.
Falconi M Oteri F Di Palma F Pandey S Battistoni A Desideri A 《Journal of computer-aided molecular design》2011,25(2):181-194
Comparative homology modelling techniques have been used to model the protein ZnuA from Salmonella enterica serovar Typhimurium using the 3D structure of the homologous protein from Escherichia coli. These two-domain proteins bind one Zn2+ atom, with high affinity, in the inter-domain cleft and possess a histidine-rich loop in the N-terminal domain. Alternative
structures of the ZnuA histidine-rich loop, never resolved by the X-ray diffraction method, have been modelled. A model of
the apo form, one with the histidine-rich loop deleted and two alternative structures with a second zinc ion bound to the
histidine-rich loop, have been generated. In all the modelled proteins, investigated through molecular dynamics simulation,
the histidine-rich loop is highly mobile and its fluctuations are correlated to the ligand stability observed in the zinc
sites. Based on the plasticity of the histidine-rich loop and its significant effects on protein mobility a possible role
in the capture and/or transfer of the zinc ions has been suggested. 相似文献
126.
Riccardo?A.?Siliprandi Stefano?Zanini Elisa?Grimoldi Francesco?S.?Fumagalli Ruggero?BarniEmail author Claudia?Riccardi 《Plasma Chemistry and Plasma Processing》2011,31(2):353-372
An atmospheric pressure dielectric barrier plasma discharge has been used to study a thin film deposition process. The DBD
device is enclosed in a vacuum chamber and one of the electrodes is a rotating cylinder. Thus, this device is able to simulate
continuous processing in arbitrary deposition condition of pressure and atmosphere composition. A deposition process of thin
organosilicon films has been studied reproducing a nitrogen atmosphere with small admixtures of hexamethyldisiloxane (HMDSO)
vapours. The plasma discharge has been characterized with optical emission spectroscopy and voltage-current measurements.
Thin films chemical composition and morphology have been characterized with FTIR spectroscopy, atomic force microscopy (AFM)
and contact angle measurements. A strong dependency of deposit character from the HMDSO concentration has been found and then
compared with the same dependency of a typical low pressure plasma enhanced chemical vapour deposition process. 相似文献
127.
128.
Di Santo G Blankenburg S Castellarin-Cudia C Fanetti M Borghetti P Sangaletti L Floreano L Verdini A Magnano E Bondino F Pignedoli CA Nguyen MT Gaspari R Passerone D Goldoni A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(51):14354-14359
Scratching the surface: Formation of a monolayer of 2H-tetraphenylporphyrins (2H-TPP) on Ag(111), either by sublimation of a multilayer in the range 525-600?K or by annealing (at the same temperature) a monolayer deposited at room temperature, induces a chemical modification of the molecules. Rotation of the phenyl rings into a flat conformation is observed and tentatively explained, by using DFT calculations, as a peculiar reaction due to molecular dehydrogenation. 相似文献
129.
Bruna P Baldi G Pineda E Serrano J Suck JB Crespo D Monaco G 《The Journal of chemical physics》2011,135(10):101101
Using high resolution inelastic x-ray scattering we studied the collective dynamics of the Pd(77)Si(16.5)Cu(6.5) metallic glass, focusing on the energy-momentum region where the boson peak appears. The dispersion relation and the width of the acoustic excitations are determined showing how the longitudinal acoustic modes maintain their dispersive character for frequencies well above the boson peak frequencies. Moreover, we prove that close to these frequencies there is a softening of the apparent sound speed indicating a failure of the Debye continuum approximation at the boson peak frequencies and challenging previous results on other metallic glasses. 相似文献
130.
Amorati R Attanasi OA Favi G Menichetti S Pedulli GF Viglianisi C 《Organic & biomolecular chemistry》2011,9(5):1352-1355
Hydrogenated cardanol and cardols, contained in industrial grade cardanol oil and obtained by distillation of the raw "cashew nut shell liquid" (CNSL), are easily transformed into efficient 4-thiaflavane antioxidants bearing a long alkyl chain on A ring and a catechol group on B ring. 相似文献