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81.
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
82.
Simple, reproducible preparative methods are described for the production of the title compounds from diacetone glucose. 相似文献
83.
84.
Summary We describe the simplest system which shows stochastic resonance. A linear(ized) theory for white and (almost) arbitrarily
coloured noise is presented. The presented new system has new, unique properties which originate from itsnon-dynamical character; for example, the strength and phase shift of periodic response of the system is independent of the frequency.
Experiments have been carried out with the following noise processes: (physical) white noise, (physical) Lorentzian noise
and (physical) 1/f noise. With a small extension of the system, its linear-response regime can be significantly increased. As the system is
similar to some simple models of neurones, the new results might have not only physical but also biological importance.
Paper presented at the International Workshop “Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena”, Elba, 5–10 June 1994. 相似文献
85.
Multiphoton ionisation of different order was measured from the energy levels of the atoms He, excited in a low current glow discharge. 相似文献
86.
The general intensity dependence of the five-photon ionization probability of triplet metastable helium was measured. 相似文献
87.
Dynamic and stepwise purity test techniques were compared, and it was established that in dynamic measurement the sample in many cases can not be considered to be in a state of equilibrium from the thermodynamic aspect. The problems of the measuring time and the accuracy of the results are discussed for the two-peak method, applicable for the processing of data obtained by the stepwise technique. It was established that the two-peak method can be improved. By using several peaks, the accuracy of the results and measuring time can be optimized. 相似文献
88.
J. Kiss 《Helvetica chimica acta》1967,50(5):1423-1430
In the sulfatide fraction of beef spinal-cord, isolated according to the method of BLIX [9] and LEES [14], there are also sulfatides present derived from 2S, 3R-1, 3-dihydroxy-2-amino-octadecane. 相似文献
89.
An experimentally accessible algorithm for changing the time scale associated with a dynamical variable is proposed. In general, a differential controller can be applied to (a) identify the essential species in oscillatory systems and (b) explore their role in the feedback loops. Here, we report on classifying electrochemical oscillators by changing the time scale over which the electrode potential varies; the type of different electrochemical oscillators is identified based on whether the controlled modification of pseudo-capacitance induces or suppresses current oscillations. 相似文献
90.
Szilágyi I Kele Z Labádi I Hernadi K Pálinkó I Kiss T 《Rapid communications in mass spectrometry : RCM》2005,19(19):2878-2882