The “accumulation effect” of positrons in the stack of foils, detected by measurements of the positron implantation profile

2013 ◽  
Vol 114 (22) ◽  
pp. 224901 ◽  
Author(s):  
Jerzy Dryzek ◽  
Krzysztof Siemek
Keyword(s):  
Accumulation Effect ◽  
Implantation Profile

scholarly journals The detection of reverse accumulation effect in the positron annihilation profile of stack of aluminum and silver foils

Nukleonika ◽  
2015 ◽  
Vol 60 (4) ◽  
pp. 713-716 ◽  
Author(s):  
Jerzy Dryzek ◽  
Krzysztof Siemek
Keyword(s):  
Absorption Coefficient ◽  
Positron Annihilation ◽  
Linear Absorption Coefficient ◽  
Linear Absorption ◽  
Theoretical Profile ◽  
Accumulation Effect ◽  
The Subject ◽  
Implantation Profile ◽  
Good Agreement

Abstract The implantation profile of positrons emitted from 22Na into a stack of aluminum and silver foils is the subject of the presented report. The characteristic dimple in the profile behind the Ag foil was detected. This effect arises from the differences in the linear absorption coefficient of aluminum and silver. The good agreement between the theoretical profile obtained within the multiscattering model and experimental one was achieved. The observed phenomenon can affect the positron annihilation characteristics measured for the inhomogeneous samples.

Isolation of Pediococcus Strain from Nuruk and Anti-Lipid Accumulation Effect of Ornithine-Containing Makgeolli on 3T3-L1 Cells

2015 ◽  
Vol 44 (9) ◽  
pp. 1264-1269
Author(s):  
Jin-Seon Yook ◽  
Suk-Heung Oh ◽  
Su-Gon Kim ◽  
Jo-Seph Lee ◽  
Eun-Gyung Mun ◽  
...  
Keyword(s):  
Lipid Accumulation ◽  
Accumulation Effect

Modeling temperature rise in multi-track reciprocating frictional sliding

2021 ◽  
pp. 135065012098823
Author(s):  
Thierry A Blanchet
Keyword(s):  
Temperature Rise ◽  
Peclet Number ◽  
Maximum Temperature ◽  
Uniform Heat Flux ◽  
Heat Accumulation ◽  
Stroke Length ◽  
Péclet Number ◽  
Maximum Temperature Rise ◽  
Rectangular Patch ◽  
Accumulation Effect

As in various manufacturing processes, in sliding tests with scanning motions to extend the sliding distance over fresh countersurface, temperature rise during any pass is bolstered by heating during prior passes over neighboring tracks, providing a “heat accumulation effect” with persisting temperature rises contributing to an overall temperature rise of the current pass. Conduction modeling is developed for surface temperature rise as a function of numerous inputs: power and size of heat source; speed and stroke length, and track increment of scanning motion; and countersurface thermal properties. Analysis focused on mid-stroke location for passes of a square uniform heat flux sufficiently far into the rectangular patch being scanned from the first pass at its edge that steady heat accumulation effect response is adopted, focusing on maximum temperature rise experienced across the pass' track. The model is non-dimensionalized to broaden the applicability of the output of its runs. Focusing on practical “high” scanning speeds, represented non-dimensionally by Peclet number (in excess of 40), applicability is further broadened by multiplying non-dimensional maximum temperature rise by the square root of Peclet number as model output. Additionally, investigating model runs at various non-dimensional speed (Peclet number) and reciprocation period values, it appears these do not act as independent inputs, but instead with their product (non-dimensional stroke length) as a single independent input. Modified maximum temperature rise output appears to be a function of only two inputs, increasing with decreasing non-dimensional values of stroke length and scanning increment, with outputs of models runs summarized compactly in a simple chart.

scholarly journals The Accumulation Effect

2005 ◽  
Vol 26 (2) ◽  
pp. 35-52 ◽  
Author(s):  
Raivo Palmaru
Keyword(s):  
Public Opinion ◽  
Political Parties ◽  
Local Elections ◽  
Political Preferences ◽  
Public Opinion Surveys ◽  
Accumulation Effect ◽  
General Elections ◽  
The Media ◽  
Election Results ◽  
Prevailing View

Abstract Although numerous studies over the past 20 years have revealed a clear connection between content analysis statistics and the results of public opinion surveys, the media’s “minimal effects” hypothesis still remains the overwhelmingly prevailing view. Among other things, it is not clear which of the two influences the other: Do people’s political preferences influence the media or do the media influence people’s preferences? In order to test this, the results of the 1999 and 2003 general elections and the 2002 local elections in Estonia, as well as the results of current public opinion surveys, were compared to the coverage given to the campaigning parties in the largest Estonian newspapers. The analysis showed that the coverage of political parties in the print media, as determined by the frequency of valuative notations, described the election results to a great extent. It is noteworthy that a change in media content was followed by a change in public opinion. At the same time, an accumulation effect became obvious: The voters’ preferences for political parties accumulated diachronically during the course of several weeks based on the information that was available to them.

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