High energy (p, 2p) reactions and proton binding energies

1958 ◽  
Vol 7 ◽  
pp. 10-23 ◽  
Author(s):  
H. Tyrén ◽  
Peter Hillman ◽  
Th.A.J. Maris
2011 ◽  
Vol 306-307 ◽  
pp. 251-254 ◽  
Author(s):  
Shreyas S. Pitale ◽  
L.L. Noto ◽  
I.M. Nagpure ◽  
O.M. Ntwaeaborwa ◽  
J.J. Terblans ◽  
...  

Zn3Ta2O8 is a promising host for low voltage cathodoluminescence (CL) applications. Surface chemical stability during low voltage electron beam excitation is a prime concern for phosphors to be used in various new generation information displays. Photoluminescence (PL) and CL characteristics of the Zn3Ta2O8 host doped with Pr3+ are presented. The phosphors were synthesized via solid-state reaction route at 1100°C. Red CL or PL with a maximum at 611 nm, attributed to the 1D2-3H4 transition of the Pr3+ ion, was observed at room temperature under high energy electron (2 keV, 12 μA) or a monochromatic xenon lamp (257 nm) irradiation. Electron stimulated chemical changes on the surface of the Zn3Ta2O8:Pr3+ phosphor during an electron beam exposure from 0-350 C/cm2 was monitored using Auger electron spectroscopy. The CL exhibited only a 20% loss in the original intensity during the continuous electron beam exposure. X-ray photoelectron spectroscopy (XPS) was used to estimate the redox states of the chemical constituents and a comparison of binding energies was made with the standard Ta2O5 and ZnO compounds. A correlation between the structural configuration of Zn3Ta2O8 and the XPS data is also established.


1964 ◽  
Vol 13 (10) ◽  
pp. 341-343 ◽  
Author(s):  
U. Amaldi ◽  
G. Campos Venuti ◽  
G. Cortellessa ◽  
C. Fronterotta ◽  
A. Reale ◽  
...  

Computation ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 91
Author(s):  
Konstantin P. Katin ◽  
Valeriy B. Merinov ◽  
Alexey I. Kochaev ◽  
Savas Kaya ◽  
Mikhail M. Maslov

We combined ab initio molecular dynamics with the intrinsic reaction coordinate in order to investigate the mechanisms of stability and pyrolysis of N4 ÷ N120 fullerene-like nitrogen cages. The stability of the cages was evaluated in terms of the activation barriers and the activation Gibbs energies of their thermal-induced breaking. We found that binding energies, bond lengths, and quantum-mechanical descriptors failed to predict the stability of the cages. However, we derived a simple topological rule that adjacent hexagons on the cage surface resulted in its instability. For this reason, the number of stable nitrogen cages is significantly restricted in comparison with their carbon counterparts. As a rule, smaller clusters are more stable, whereas the earlier proposed large cages collapse at room temperature. The most stable all-nitrogen cages are the N4 and N6 clusters, which can form the van der Waals crystals with densities of 1.23 and 1.36 g/cm3, respectively. The examination of their band structures and densities of electronic states shows that they are both insulators. Their power and sensitivity are not inferior to the modern advanced high-energy nanosystems.


2012 ◽  
Vol 545 ◽  
pp. 148-152
Author(s):  
Jaafar Mohd Hilmi ◽  
Rusdi Roshidah ◽  
Mohamed Nor Sabirin ◽  
Rosiyah Yahya ◽  
Norlida Kamarulzaman

One of the aspects most intensively researched in the continuing improvisation of lithium battery is the search for high capacity, high energy density and high performance cathode materials. Substitution of the electroactive elements with heteroatoms is one of the promising methods. In this study, a potential cathode material with a layered structure was successfully synthesized via a sol-gel method. As a comparison, the well-known LiMn1/3Co1/3Ni1/3O2(LiMn0.333Co0.333Ni0.333O2) was also synthesized using exactly the same method and conditions. Both materials were characterized using simultaneous thermogravimetric analysis (STA), X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM) and X-ray photoelectron spectroscopy (XPS). The stoichiometries of the compounds were also confirmed through energy-dispersive X-ray spectroscopy (EDX) measurement. XRD results show that both compounds are single phase and impurity-free with well-ordered hexagonal layered structure characteristics of R-3m space group. Both compounds also show similar morphologies with well-formed crystals and clean surfaces as depicted by the SEM images. XPS measurement reveals that the introduction of chromium into LiMn1/3Co1/3Ni1/3O2results in a considerable change in the chemical environment as observed by significant changes in the binding energies (BE) of manganese, cobalt and nickel respectively.


The variation method is employed to calculate the binding energy of the triton assuming charge-independent, two-body, Yukawa shape interactions between nucleons in which tensor forces are included. More complete trial wave functions are used than employed hitherto in such calculations, and it is found that an interaction of Yukawa shape with constants adjusted to fit the observed data on the binding energy, quadrupole moment and magnetic moment of the deuteron, the low-energy and high-energy scattering of neutrons by protons, the photodisintegration of the deuteron and the coherent scattering of slow neutrons gives an approximately correct binding energy for the triton. Calculations are also carried out with interactions of the same type but with different constants. The exchange character of the forces remains unimportant. It is confirmed that the difference in the binding energies of 3 H and 3 He can be ascribed to the effect of Coulomb repulsion between the protons in the latter nucleus. The wave functions found are used to compute the magnetic moments of the two nuclei but do not contain sufficient admixture of P component to explain the observed values.


2017 ◽  
Vol 16 (08) ◽  
pp. 1750072
Author(s):  
Qiang Cao ◽  
Ji Jun Xiao ◽  
Pei Gao ◽  
Shen Shen Li ◽  
Feng Zhao ◽  
...  

Molecular dynamics (MD) simulations were carried out to study the polymer-bonded explosives (PBXs) where the explosive base was the well-known high energy co-crystal compound, 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexazaisowurtzitane/2,4,6-trinitrotoluene (CL-20/TNT), and the polymer binders were fluorine rubber (F[Formula: see text], fluorine resin (F[Formula: see text], polyvinyl acetate (PVAc) and polystyrene (PS), respectively. The binding energies, pair correlation functions (PCFs) and mechanical properties of the PBXs were reported. According to our theoretical results of binding energies, the compatibility of the PBXs is predicted to be in the following order: CL-20/TNT/PVAc[Formula: see text] CL-20/TNT/F[Formula: see text] [Formula: see text] CL-20/TNT/PS [Formula: see text] CL-20/TNT/F[Formula: see text]. The binding energies of the PBXs on three crystalline surfaces, (100), (001), (010), of the CL-20/TNT co-crystal were also compared: CL-20/TNT(100)[Formula: see text]CL-20/TNT(001)[Formula: see text]CL-20/TNT(010) for F[Formula: see text], F[Formula: see text], and PS; CL-20/TNT(001)[Formula: see text]CL-20/TNT(100)[Formula: see text]CL-20/TNT(010) for PVAc. The PCF analysis reveals that there exist H-bonds between H and O, F, and N atoms on all three interfaces and among all H-bonds, N H-bond has the fewest number. For the CL-20/TNT co-crystal, the moduli can be reduced by adding a small amount of the polymer binders but the ductility can be prolonged only by F[Formula: see text] and F[Formula: see text].


2000 ◽  
Vol 609 ◽  
Author(s):  
Shuran Sheng ◽  
Edward Sacher ◽  
Arthur Yelon

ABSTRACTLight- and annealing-induced structural changes in undoped hydrogenated amorphous silicon (a-Si:H), pure amorphous silicon (a-Si) and crystalline silicon (c-Si) have been investigated in detail by X-ray photoemission spectroscopy (XPS). Both the Si2s and Si2p peaks in a-Si:H films were found to shift simultaneously to lower binding energies by the same amount with illumination time, and nearly reach saturation at about 0.06 eV after one hour of light-soaking at the intensity used. In contrast to the metastable changes in electronic properties [Staebler-Wronski effect (SWE)], the light-induced shifts in both peaks are unstable even at room temperature and can be reversed by annealing with a lower activation energy than that for the SWE. The absence of metastable XPS changes in pure a-Si and c-Si suggests that hydrogen is actively involved in the light-induced structural changes. Furthermore, visible light exposure produces XPS changes in a-Si:H less effectively than X-ray irradiation, despite its much higher incident intensity, indicating a high-energy photon irradiation effect. Our present results suggest that essentially the whole Si network structure is affected by light-soaking or X-ray irradiation, and becomes more stable after repeated irradiation-annealing training. These structural changes may be an independent metastable phenomenon or a precursor process of the SWE.


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