scholarly journals ELECTRON-STIMULATED DESORPTION OF LITHIUM ATOMS ADSORBED ON THE SURFACE OF GOLD-LITHIUM INTERMETALLIC

Author(s):  
Юрий Александрович Кузнецов ◽  
Михаил Николаевич Лапушкин

Получена тонкая пленка интерметаллида LiAu при комнатной температуре при напылении атомов Li на слой адсорбированного золота на поверхности вольфрама. Исследованы процессы электронно-стимулированной десорбции (ЭСД) атомов Li с поверхности LiAu. Показано, что ЭСД атомов Li может наблюлаться только в том случае, когда напылено не менее одного монослоя атомов Li и с Au . Зависимость выхода ЭСД атомов Li от количества напыленного Li и Au имеет максимум при напылении двух монослоев атомов Li на Au. Полученные результаты свидетельствуют о формировании LiAu различной стехиометрии: от LiAu с дефицитом атомов лития до LiAu при напылении двух монослоев атомов Li. В энергетическом распределении по кинетическим энергиям десорбирующихся атомов Li обнаружено два пика: высокоэнергетический и низкоэнергетический. Первый из них связан с десорбцией атомов Li из LiAu, а второй в десорбцией атомов Li из верхнего монослоя атомов Li. A thin film of the intermetallic compound LiAu was obtained at room temperature by deposition Li atoms onto a layer of adsorbed gold on the tungsten surface. The processes of electron-stimulated desorption of Li atoms from the surface are investigated. It is shown that electron-stimulated desorption of Li atoms can be observed only in the case when at least one monolayer of Li and Au atoms is deposited. The dependence of the electron-stimulated desorption yield of Li atoms on the amount of deposited has a maximum when two monolayers of atoms Li are deposited on Au . The results obtained indicate the LiAu formation of various stoichiometry: from with a deficit of lithium atoms to the deposition of two monolayers of atoms. In the kinetic energy distribution of desorbed Li atoms, two peaks were found: high-energy and low-energy. The first of them is associated with the desorption of Li atoms from LiAu, and the second with the desorption of Li atoms from the upper monolayer of Li atoms.

2019 ◽  
Vol 61 (8) ◽  
pp. 1526
Author(s):  
Ю.А. Кузнецов ◽  
М.Н. Лапушкин ◽  
Е.В. Рутьков ◽  
Н.Р. Галль

Electron stimulated desorption (ESD) of neutral atomic Cs from graphene on Ir has been studied for two cases: when Cs intercalation does present and when it does not take place. Two peaks have been found at desorbed atom energy distribution: high-energy (HE) at the energy of 0.36 eV and low-energy (LE) one at the energy of 0.13 eV. HE peak has been observed for both cases, we attribute it with excitation of 2s carbon core level. LE peak was observed only when intercalation does not take place; we attribute it with excitation of 4f and 5p core levels of Ir. A model is put forward to describe atomic Cs ESD; we proposed that graphene on Ir acts as dielectric in the processes discussed above.


Author(s):  
Юрий Александрович Кузнецов ◽  
Михаил Николаевич Лапушкин

Создан ультратонкий слой интерметаллида KAu при комнатной температуре при напылении атомов калия на слой адсорбированного золота на поверхности вольфрама. Исследованы процессы электронно-стимулированной десорбции атомов K с поверхности KAu. Найдены квазирезонансные пики в зависимости выхода ЭСД от энергии возбуждения при 64 и 82 эВ, которые соответствуют возбуждению остовных уровней Au 5р и Au 5р. Полученные результаты свидетельствуют о формировании KAu различной стехиометрии: от KAu до KAu. Показано, что интерметаллид KAu, полученный при комнатной температуре, как полученный ранее KAu при 1000K, является полупроводником. Предложена модель электронно-стимулированной десорбции атомов K в системе K/KAu/Au/W. An ultrathin intermetallic layer KAuwas created at room temperature by depositing potassium atoms on adsorbed gold layer on the tungsten surface. The processes of electron-stimulated desorption of K atoms from the KAu surface are investigated. Quasi-resonance peaks are found in the dependence of the ESD yield on the excitation energy at 64 and 82 eV, which correspond to the excitation of the core levels Au 5p and Au 5p. The obtained results indicate the formation KAu of different stoichiometry: from KAu to KAu . It is shown that the intermetallic compound KAu created at room temperature is a semiconductor, as it was previously obtained at 1000 K. A model of electron-stimulated desorption of K atoms in the K / KAu / Au / W system is proposed.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
H. K. Lin ◽  
C. W. Huang ◽  
Y. H. Lin ◽  
W. S. Chuang ◽  
J. C. Huang

AbstractAg50Cu50 films were deposited on glass substrates by a sputtering system. Effects of accumulated energy on nanoparticle formation in pulse-laser dewetting of AgCu films were investigated. The results showed that the properties of the dewetted films were found to be dependent on the magnitude of the energy accumulated in the film. For a low energy accumulation, the two distinct nanoparticles had rice-shaped/Ag60Cu40 and hemispherical/Ag80Cu20. Moreover, the absorption spectra contained two peaks at 700 nm and 500 nm, respectively. By contrast, for a high energy accumulation, the nanoparticles had a consistent composition of Ag60Cu40, a mean diameter of 100 nm and a peak absorption wavelength of 550 nm. Overall, the results suggest that a higher Ag content of the induced nanoparticles causes a blue shift of the absorption spectrum, while a smaller particle size induces a red shift.


2007 ◽  
Vol 22 (9) ◽  
pp. 2582-2589 ◽  
Author(s):  
M. Cai ◽  
S.C. Langford ◽  
J.T. Dickinson ◽  
L.E. Levine

The evolution of the kinetic energy distribution of photoelectrons from a cube-oriented aluminum sample during tensile deformation was probed with a retarding field energy analyzer. Because of the anisotropy of the aluminum work function, the electron-energy distribution is altered as the area fractions of the major surface planes change during deformation. In cube-textured aluminum, deformation reduces the {100} area fraction and the relatively low energy electrons from these surfaces. Conversely, the {110} and {111} area fractions and the relatively high energy electrons from these surfaces both increase. These changes are quantitatively consistent with texture analysis by electron backscattered diffraction (EBSD). They reflect deformation-induced production of {111} surfaces by slip and the exposure of {110} surfaces by grain rotation. Photoelectron kinetic energy measurements supplement EBSD measurements and are readily acquired in real-time.


DYNA ◽  
2020 ◽  
Vol 87 (215) ◽  
pp. 174-179
Author(s):  
Freddy Fuentes Robayo ◽  
Rafael Maria Gutierrez Salamanca

This paper presents the performance of a 3GEM in terms of identification of high and low beta energy radiation sources through the energy distribution of the main beta radiation sources used for industrial application 90Sr and 204Tl. We compare the beta radiation theoretical energy loss into the drift zone with experimental energy distribution at different 3GEM voltages. The experimental results show that the Most Probable Value (MPV) of the fitted Landau distribution obtained from 90Sr and 204Tl obtained a degree of error lower than 14% in comparison to the theoretical calculation. Additionally, high energy beta radiation source (90Sr) is identified in comparison to low energy (204Tl) - taking into account the MPV and sigma values from the fitted Landau distribution. These results are essential to design and implement a new application that utilizes the performance and special characteristics of the 3GEM for beta radiation detection and identification.


Author(s):  
Michael C. Reade ◽  
Peter D. Thomas

Bullets and other projectiles cause ballistic trauma. Explosions wound by the effect of a blast pressure wave, penetrating fragments propelled by the explosion, the mass movement of gas interacting with the casualty or the environment, and miscellaneous effects. Most blast casualties surviving to hospital care will not have significant pressure wave injury, but some will. Blast fragmentation most commonly resembles other types of low energy transfer ballistic trauma.. The effect of bullets depends on the kinetic energy transferred and the nature of the tissues struck, with energy transfer partly determined by bullet design. Low energy transfer bullets wound by crushing and laceration, limited to the tissues struck. High energy bullets may impart kinetic energy to surrounding tissues, causing a temporary cavity which sucks in debris and damages tissues sometimes well beyond the bullet track. Predicting the extent of devitalization can be difficult at the time of initial inspection. Wound contamination, particularly with soil, may modify the usual conservative approach to initial debridement.


2015 ◽  
Vol 7 (48) ◽  
pp. 26381-26386 ◽  
Author(s):  
Chang Won Ahn ◽  
Gantsooj Amarsanaa ◽  
Sung Sik Won ◽  
Song A Chae ◽  
Dae Su Lee ◽  
...  

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