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91.
92.
The adsorption and surface reaction of cyanogen on clean and oxygen covered Cu(111) have been investigated. From electron energy loss measurements, thermal desorption spectroscopy and electron beam effects in Auger spectroscopy, it is proposed that cyanogen adsorbs dissociatively on Cu(111) at 300 K. The activation energy for the desorption was calculated to be 180 kJ/mol. Cyanogen adsorption onto oxygen predosed Cu(111) is inferred to produce the NCO surface species. This interpretation was aided by data of electron energy loss measurements and from HNCO adsorption onto Cu(111) at 300 K. A reaction began in the co-adsorbed layer above 400 K, yielding CO2 and N2. 相似文献
93.
94.
Let \({\mathbb{N}}\) denote the set of all nonnegative integers. Let \({k \ge 3}\) be an integer and \({A_{0} = \{a_{1}, \dots, a_{t}\} (a_{1} < \cdots < a_{t})}\) be a nonnegative set which does not contain an arithmetic progression of length k. We denote \({A = \{a_{1}, a_{2}, \ldots{}\}}\) defined by the following greedy algorithm: if \({l \ge t}\) and \({a_{1}, \dots{}, a_{l}}\) have already been defined, then \({a_{l+1}}\) is the smallest integer \({a > a_{l}}\) such that \({\{a_{1}, \dots, a_{l}\} \cup \{a\}}\) also does not contain a k-term arithmetic progression. This sequence A is called the Stanley sequence of order k generated by A0. We prove some results about various generalizations of the Stanley sequence. 相似文献
95.
Yu. N. Khaydukov B. Nagy J. -H. Kim T. Keller A. Rühm Yu. V. Nikitenko K. N. Zhernenkov J. Stahn L. F. Kiss A. Csik L. Bottyán V. L. Aksenov 《JETP Letters》2013,98(2):107-110
Here we report on a feasibility study aiming to explore the potential of Polarized Neutron Reflectometry (PNR) for detecting the inverse proximity effect in a single superconducting/ferromagnetic bilayer. Experiments, conducted on the V (40 nm)/Fe (1 nm) S/F bilayer, have shown that experimental spin asymmetry measured at T = 0.5T C is shifted towards higher Q values compared to the curve measured at T = 1.5T C . Such a shift can be described by the appearance in superconducting vanadium of magnetic sublayer with a thickness of 7 nm and a magnetization of +0.8 kG. 相似文献
96.
It is known that phosphinic acids do not undergo direct esterification under conventional conditions. However, the reaction may take place on microwave irradiation. 1‐Hydroxy‐3‐phospholene 1‐oxides, 1‐hydroxy‐phospholane 1‐oxides, and a 1‐hydroxy‐1,2,3,4,5,6‐hexahydrophosphinine 1‐oxide were esterified with n‐pentanol, i‐pentanol, n‐octanol, and i‐octanol(2‐ethylhexanol). The phosphinates prepared in 50%–94% yield are all new compounds, and a number of them are useful intermediates. 相似文献
97.
A method for engineering the global behavior of populations of rhythmic elements is presented. The framework, which is based on phase models, allows a nonlinear time-delayed global feedback signal to be constructed which produces an interaction function corresponding to the desired behavior of the system. It is shown theoretically and confirmed in numerical simulations that a polynomial, delayed feedback is a versatile tool to tune synchronization patterns. Dynamical states consisting of one to four clusters were engineered to demonstrate the application of synchronization engineering in an experimental electrochemical system. 相似文献
98.
La Cognata M Spitaleri C Mukhamedzhanov AM Irgaziev B Tribble RE Banu A Cherubini S Coc A Crucillà V Goldberg VZ Gulino M Kiss GG Lamia L Mrazek J Pizzone RG Puglia SM Rapisarda GG Romano S Sergi ML Tabacaru G Trache L Trzaska W Tumino A 《Physical review letters》2008,101(15):152501
The 18O(p,alpha)15N reaction is of primary importance in several astrophysical scenarios, including fluorine nucleosynthesis inside asymptotic giant branch stars as well as oxygen and nitrogen isotopic ratios in meteorite grains. Thus the indirect measurement of the low energy region of the 18O(p,alpha)15N reaction has been performed to reduce the nuclear uncertainty on theoretical predictions. In particular the strength of the 20 and 90 keV resonances has been deduced and the change in the reaction rate evaluated. 相似文献
99.
100.
Jójárt B Kiss R Viskolcz B Keseru GM 《Journal of chemical information and modeling》2008,48(6):1199-1210
Molecular dynamics (MD) simulations in a membrane-embedded environment were carried out on the homology model of the human histamine H4 receptor (hH4R) alone and in complex with its endogenous activator histamine and with the first reported selective hH4R antagonist JNJ7777120. During the simulation of the histamine-hH4R complex, considerable changes occurred in the hH4R structure as well as in the interaction pattern of histamine at the binding site. These changes are in agreement with experimental data published on GPCR activation. In particular, the intracellular side of TM helix VI moved significantly away from TM helices III and VII. Moreover, histamine formed an interaction with Asn147 (4.57) that was previously proved to be important in hH4R activation. Results of the MD simulations of the native hH4R and the JNJ7777120-hH4R complex suggest that these models represent an inactive conformation of hH4R. MD simulation in the presence of JNJ7777120 resulted in the movement of the intracellular side of TM helix VI in the direction of TM helix III. Snapshots of the simulations may serve as functionally relevant models in the development of novel hH4R ligands in the future. 相似文献