scholarly journals Systematic study of favoredα-decay half-lives of closed shell odd-Aand doubly-odd nuclei related to ground and isomeric states

2016 ◽  
Vol 94 (2) ◽  
Author(s):  
Xiao-Dong Sun ◽  
Ping Guo ◽  
Xiao-Hua Li
Keyword(s):  
Systematic Study ◽  
Closed Shell ◽  
Isomeric States

Novel aromatics blended with a σ-flavor

2006 ◽  
Vol 78 (4) ◽  
pp. 685-697 ◽  
Author(s):  
Koichi Komatsu
Keyword(s):  
Molecular Orbital ◽  
Systematic Study ◽  
Structural Modification ◽  
Radical Cations ◽  
Closed Shell ◽  
Conjugated Systems ◽  
Highest Occupied Molecular Orbital ◽  
Bicyclic System ◽  
Kinetic Effects ◽  
Sulfur Containing

We present the results of our systematic study on the synthesis, structures, and electronic properties of a series of cyclic π-conjugated systems with monocyclic six- to eight-membered rings as well as polycyclic benzenoid aromatics, which are fully surrounded by rigid bicyclic σ-frameworks such as bicyclo[2.2.2]octene (BCO). The study has also been extended to sulfur-containing systems such as thiophene, 1,2- and 1,4-dithiins, and oligothiophene. Such a structural modification using bicyclic frameworks is effective in elevation of the highest occupied molecular orbital (HOMO) levels of neutral π-systems and in remarkable stabilization of the corresponding cationic systems by both σ-π conjugation and kinetic effects. This has led to various new cationic π-conjugated systems such as highly stable radical cations as well as closed-shell mono- and dications, which could have never been attained by any other conventional techniques. The properties of benzene and entirely planar cyclooctatetraene (COT) possessing a marked bond fixation caused by structural modification with a strained bicyclic system (i.e., bicyclo[2.1.1]hexene, BCH) are also described.

scholarly journals Systematic Study of Quasifission in 48Ca-induced reactions

2020 ◽  
Vol 232 ◽  
pp. 03007
Author(s):  
B. M. A. Swinton-Bland ◽  
D. J. Hinde ◽  
M. Dasgupta ◽  
D. Y. Jeung ◽  
E. Williams ◽  
...  
Keyword(s):  
Systematic Study ◽  
Fission Fragment ◽  
Closed Shell ◽  
Superheavy Elements ◽  
Heavy Nuclei ◽  
Detailed Understanding ◽  
Projectile Nucleus ◽  
The Stability ◽  
Heaviest Elements ◽  
Closed Shells

The production of superheavy elements through the fusion of two heavy nuclei is severely hindered by the quasifission process, which results in the fission of heavy systems before an equilibrated compound nucleus (CN) can be formed. The heaviest elements have been synthesised using 48Ca as the projectile nucleus. However, the use of 48Ca in the formation of new superheavy elements has been exhausted, thus a detailed understanding of the properties that made 48Ca so successful is required. Measurements of mass-angle distributions allow fission fragment mass distribution widths to be determined. The effect of the orientation of prolate deformed target nuclei is presented. Closed shells in the entrance channel are also shown to be more important than the stability of the formed CN in reducing the quasifission component, with reduced mass widths for reactions with the closed shell target nuclei 144Sm and 208Pb. Comparison to mass widths for 48Ti-induced reactions show a significant increase in the mass width compared to 48Ca-induced reactions, highlighting the difficulty faced in forming new superheavy elements using projectiles with higher atomic number than 48Ca.

scholarly journals Systematic study of the effect of short range correlations on the form factors and densities of s-p-d shell nuclei

2020 ◽  
Vol 9 ◽  
pp. 279
Author(s):  
H. C. Moustakidis ◽  
S. E. Massen
Keyword(s):  
Systematic Study ◽  
Short Range ◽  
Form Factors ◽  
Closed Shell ◽  
Open Shell ◽  
Oscillator Parameter ◽  
Charge Form ◽  
Closed Shell Nuclei ◽  
The One ◽  
Short Range Correlations

Analytical expressions of the one- and two-body terms in the cluster expansion of the charge form factors and densities of the s-p and s-d shell nuclei with N=Z are derived. They depend on the harmonic oscillator parameter 6 and the parameter β which originates from the Jastrow correlation function. These expressions are used for the systematic study of the effect of short range correlations on the form factors and densities and of the mass dependence of the parameters ò and β. These parameters have been determined by fit to the experimental charge form factors. The inclusion of the correlations reproduces the experimental charge form factors at the high momentum transfers (q > 2 fm^-1). It is found that while the parameter β is almost constant for the closed shell nuclei, 4He, 16O and 40Ca, its values are larger (less correlated systems) for the open shell nuclei, indicating a shell effect in the closed shell nuclei.

Quantitative parallel EELS spectrum imaging developed as a new tool in AEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1202-1203
Author(s):  
Gianluigi Botton ◽  
Gilles L'espérance
Keyword(s):  
Statistical Analysis ◽  
Spatial Resolution ◽  
Personal Computer ◽  
Systematic Study ◽  
Present Author ◽  
Chemical Elements ◽  
Detection Limits ◽  
Research Groups ◽  
Quantitative Performance ◽  
Spectrum Imaging

As interest for parallel EELS spectrum imaging grows in laboratories equipped with commercial spectrometers, different approaches were used in recent years by a few research groups in the development of the technique of spectrum imaging as reported in the literature. Either by controlling, with a personal computer both the microsope and the spectrometer or using more powerful workstations interfaced to conventional multichannel analysers with commercially available programs to control the microscope and the spectrometer, spectrum images can now be obtained. Work on the limits of the technique, in terms of the quantitative performance was reported, however, by the present author where a systematic study of artifacts detection limits, statistical errors as a function of desired spatial resolution and range of chemical elements to be studied in a map was carried out The aim of the present paper is to show an application of quantitative parallel EELS spectrum imaging where statistical analysis is performed at each pixel and interpretation is carried out using criteria established from the statistical analysis and variations in composition are analyzed with the help of information retreived from t/γ maps so that artifacts are avoided.

A SYSTEMATIC STUDY OF 2s2 2pk - 2s2pk+l - 2pk+2 TRANSITIONS IN MULTIPLY-CHARGED Cl IONS.

1979 ◽  
Vol 40 (C1) ◽  
pp. C1-208-C1-210 ◽  
Author(s):  
J. P. Forester ◽  
D. J. Pegg ◽  
P. M. Griffin ◽  
G. D. Alton ◽  
S. B. Elston ◽  
...  
Keyword(s):  
Systematic Study ◽  
Multiply Charged
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