scholarly journals Drieschner: Voraussage - Wahrscheinlichkeit - Objekt/CNRS: Théorie de l'information/Güttinger u. Eikemeier: Structural Stability in Physics/Blatt, Weisskopf: Theoretical Nuclear Physics/Grosse: Freie Elektronen in Festkörpern/Agarwal: X-Ray Spectroscopy -

1980 ◽  
Vol 36 (3) ◽  
pp. 81-83
Author(s):  
G. Ludwig ◽  
G. Hellbardt ◽  
H. Haken ◽  
H. Rechenberg ◽  
I. Peschel ◽  
...  
Keyword(s):  
Structural Stability ◽  
Nuclear Physics ◽  
X Ray ◽  
Théorie De L'information

scholarly journals Urca nuclide production in Type-I X-ray bursts and implications for nuclear physics studies

2020 ◽  
Vol 500 (3) ◽  
pp. 2958-2968
Author(s):  
Grant Merz ◽  
Zach Meisel
Keyword(s):  
Light Curve ◽  
Nuclear Reaction ◽  
Nuclear Physics ◽  
Thermal Structure ◽  
Reaction Rates ◽  
High Mass ◽  
Type I ◽  
Model Calculations ◽  
X Ray ◽  
Lower Temperature

ABSTRACT The thermal structure of accreting neutron stars is affected by the presence of urca nuclei in the neutron star crust. Nuclear isobars harbouring urca nuclides can be produced in the ashes of Type I X-ray bursts, but the details of their production have not yet been explored. Using the code MESA, we investigate urca nuclide production in a one-dimensional model of Type I X-ray bursts using astrophysical conditions thought to resemble the source GS 1826-24. We find that high-mass (A ≥ 55) urca nuclei are primarily produced late in the X-ray burst, during hydrogen-burning freeze-out that corresponds to the tail of the burst light curve. The ∼0.4–0.6 GK temperature relevant for the nucleosynthesis of these urca nuclides is much lower than the ∼1 GK temperature most relevant for X-ray burst light curve impacts by nuclear reaction rates involving high-mass nuclides. The latter temperature is often assumed for nuclear physics studies. Therefore, our findings alter the excitation energy range of interest in compound nuclei for nuclear physics studies of urca nuclide production. We demonstrate that for some cases this will need to be considered in planning for nuclear physics experiments. Additionally, we show that the lower temperature range for urca nuclide production explains why variations of some nuclear reaction rates in model calculations impacts the burst light curve but not local features of the burst ashes.

Structural Stability of CdSe Nanocrystallite Dispersions

1995 ◽  
Vol 400 ◽  
Author(s):  
H. Mattoussi ◽  
C.B. Murray ◽  
M.G. Bawendi ◽  
R. Ober
Keyword(s):  
Thermodynamic Properties ◽  
Structural Stability ◽  
Particle Interactions ◽  
X Ray ◽  
X Ray Scattering ◽  
Crystallite Surface ◽  
Ray Scattering

AbstractX-ray scattering at small angles (SAXS) is used to study the structure and the thermodynamic properties of dispersions of CdSe nanocrystallite particles. In particular, this study allowed us to probe the inter particle interactions, and their dependence on several relevant parameters, such as the nature and size of the capping units attached to the crystallite surface and solvent.

scholarly journals The Structural Stability of Soft Magnetic Fe-Co-Zr-W-B Metallic Glasses Investigated by the in-situ X-ray Diffraction

2014 ◽  
Vol 126 (1) ◽  
pp. 66-67
Author(s):  
S. Michalik ◽  
J. Bednarcik ◽  
P. Pawlik ◽  
R. Matija ◽  
P. Sovak
Keyword(s):  
Structural Stability ◽  
Metallic Glasses ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
X Ray

Nature of the clay - cation bond affects soil structure as verified by X-ray computed tomography

Soil Research ◽  
2012 ◽  
Vol 50 (8) ◽  
pp. 638 ◽  
Author(s):  
Alla Marchuk ◽  
Pichu Rengasamy ◽  
Ann McNeill ◽  
Anupama Kumar
Keyword(s):  
Computed Tomography ◽  
Hydraulic Conductivity ◽  
Zeta Potential ◽  
Structural Stability ◽  
Structural Parameters ◽  
Pore Connectivity ◽  
X Ray ◽  
Clay Dispersion ◽  
X Ray Computed ◽  
Cation Ratio

Non-destructive X-ray computed tomography (µCT) scanning was used to characterise changes in pore architecture as influenced by the proportion of cations (Na, K, Mg, or Ca) bonded to soil particles. These observed changes were correlated with measured saturated hydraulic conductivity, clay dispersion, and zeta potential, as well as cation ratio of structural stability (CROSS) and exchangeable cation ratio. Pore architectural parameters such as total porosity, closed porosity, and pore connectivity, as characterised from µCT scans, were influenced by the valence of the cation and the extent it dominated in the soil. Soils with a dominance of Ca or Mg exhibited a well-developed pore structure and pore interconnectedness, whereas in soil dominated by Na or K there were a large number of isolated pore clusters surrounded by solid matrix where the pores were filled with dispersed clay particles. Saturated hydraulic conductivities of cationic soils dominated by a single cation were dependent on the observed pore structural parameters, and were significantly correlated with active porosity (R2 = 0.76) and pore connectivity (R2 = 0.97). Hydraulic conductivity of cation-treated soils decreased in the order Ca > Mg > K > Na, while clay dispersion, as measured by turbidity and the negative charge of the dispersed clays from these soils, measured as zeta potential, decreased in the order Na > K > Mg > Ca. The results of the study confirm that structural changes during soil–water interaction depend on the ionicity of clay–cation bonding. All of the structural parameters studied were highly correlated with the ionicity indices of dominant cations. The degree of ionicity of an individual cation also explains the different effects caused by cations within a monovalent or divalent category. While sodium adsorption ratio as a measure of soil structural stability is only applicable to sodium-dominant soils, CROSS derived from the ionicity of clay–cation bonds is better suited to soils containing multiple cations in various proportions.

X-RAY TOMOGRAPHY STUDIES OF PREHISTORIC CERAMIC ARTIFACTS

2014 ◽  
Vol 27 ◽  
pp. 1460135
Author(s):  
CARMEN PAVEL ◽  
FLORIN CONSTANTIN ◽  
COSMIN IOAN SUCIU ◽  
ROXANA BUGOI
Keyword(s):  
Computed Tomography ◽  
Cultural Heritage ◽  
Nuclear Physics ◽  
Structural Information ◽  
Ct Scans ◽  
Visual Examination ◽  
X Ray ◽  
X Ray Computed ◽  
Internal Configuration ◽  
Non Destructive

X-ray Computed Tomography (CT) is a powerful non-destructive technique that can yield interesting structural information not discernible through visual examination only. This paper presents the results of the CT scans of four objects belonging to the Romanian cultural heritage attributed to the Vinča, Cucuteni and Cruceni-Belegiš cultures. The study was performed with an X-ray tomographic device developed at the Department for Applied Nuclear Physics from Horia Hulubei National Institute for Nuclear Physics and Engineering in Măgurele, Romania. This apparatus was specially designed for archaeometric studies of low-Z artifacts: ceramic, wood, bone. The tomographic investigations revealed the internal configuration of the objects and provided information about the degree to which the previous manipulations affected the archaeological items. Based on the X-ray images resulting from the CT scans, hints about the techniques used in the manufacturing of the artifacts were obtained, as well as some indications useful for conservation/restoration purposes.

scholarly journals Potentialities of the future technical improvements in the search of rare nuclear decays by bolometers

2018 ◽  
Vol 33 (09) ◽  
pp. 1843003 ◽  
Author(s):  
Fabio Bellini
Keyword(s):  
Nuclear Physics ◽  
Detection Efficiency ◽  
Neutrinoless Double Beta Decay ◽  
Double Beta Decay ◽  
Particle Identification ◽  
X Ray ◽  
High Detection ◽  
High Detection Efficiency ◽  
Hybrid Devices ◽  
Excellent Energy Resolution

Bolometers are cryogenic calorimeters which feature excellent energy resolution, low energy threshold, high detection efficiency, flexibility in choice of materials, particle identification capability if operated as hybrid devices. After 30 years of rapid progresses, they represent nowadays a leading technology in several fields: particle and nuclear physics, X-ray astrophysics, cosmology. However, further and substantial developments are required to increase the sensitivity to the levels envisioned by future researches. A review of the challenges to be addressed and potentialities of bolometers in the search for rare nuclear decays is given, with particular emphasis to the neutrinoless double beta decay physics case.

Structural Stability of Soybean Lipoxygenase-1 in Solution as Probed by Small Angle X-ray Scattering

2005 ◽  
Vol 349 (1) ◽  
pp. 143-152 ◽  
Author(s):  
Enrico Dainese ◽  
Annalaura Sabatucci ◽  
Guus van Zadelhoff ◽  
Clotilde Beatrice Angelucci ◽  
Patrice Vachette ◽  
...  
Keyword(s):  
Structural Stability ◽  
Small Angle ◽  
Soybean Lipoxygenase ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

Microdose X-ray imaging systems of the budker institute of nuclear physics and the fields of their optimal use

2015 ◽  
Vol 51 (1) ◽  
pp. 64-71 ◽  
Author(s):  
E. A. Babichev ◽  
S. E. Baru ◽  
V. V. Leonov ◽  
V. V. Porosev ◽  
G. A. Savinov
Keyword(s):  
Nuclear Physics ◽  
Imaging Systems ◽  
Budker Institute ◽  
X Ray ◽  
X Ray Imaging
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