G-value determination for 20 MeV protons

1977 ◽  
Vol 22 (3) ◽  
pp. 522-525 ◽  
Author(s):  
H Liesem
Keyword(s):  
Value Determination ◽  
G Value ◽  
Mev Protons

scholarly journals A closer look at IRSL SAR fading data and their implication for luminescence dating

2020 ◽  
Author(s):  
Annette Kadereit ◽  
Sebastian Kreutzer ◽  
Christoph Schmidt ◽  
Regina DeWitt
Keyword(s):  
Delay Time ◽  
Luminescence Dating ◽  
Measured Signal ◽  
Time Interval ◽  
Signal Loss ◽  
Post Irradiation ◽  
Delay Times ◽  
Value Determination ◽  
G Value ◽  
Signal Fading

Abstract. Feldspar, used for infrared stimulated luminescence (IRSL) dating, is known as a dosimeter which might not completely retain the environmental dose over time, therefore leading to age underestimation. The dose leakage is believed to be caused by non-thermal (anomalous) charge redistribution in the crystal and reflected in an IRSL signal which diminishes with time accordingly. After laboratory irradiation, this signal decline may be monitored by successive IRSL readouts following increasing delay times. Hence, tests of anomalous signal fading are integral steps of IRSL dating procedures applied to feldspar and feldspar-bearing polyminerals. In these measurements IR-stimulation is in most cases preceded by thermal pretreatment (preheating) of the sample. Per common practise, preheating is performed immediately after laboratory irradiation to avoid unwanted electron redistribution assumed to occur if preheating is performed immediately before the delayed IRSL-readout. Here we compile a series of single aliquot regeneration (SAR) measurements questioning this practice. As a result, the fading measurements may possibly reveal post-irradiation afterglow. The results also suggest that data curves resembling anomalous fading may be caused by insufficient control of the readout temperature waning with increasing delay time. The unwanted effects are observed best for IRSL at room-temperature and on luminescence readers with an out-of-date steering software, but they are relevant also for IRSL at elevated temperature and on modern readers, likely including novel post-IR IRSL (pIRIR) protocols. For temperatures as homogeneous as possible during IRSL readout of the (fading) dose, we recommend preheating immediately prior to (delayed) IRSL-readout in order to avoid measurement artefacts either resembling entirely anomalous fading of the IRSL-signal or increasing the true values. It should be noticed that multifold SAR protocol and measurement parameters, like e.g. the type of luminescence reader or the use of N2 flow, may further modify the course of the data values and therefore the amount of the measured signal loss in a particular time interval after laboratory irradiation. Furthermore, calculations of signal fading (g-value) should consider only IRSL-readout after a minimum delay time after laboratory irradiation to avoid including possible post-irradiation afterglow in g-value determination. The measurements compiled in the present study were performed on polymineral fine grains extracted from loess-borne samples from southern Germany and a limnic sample from Mexico. Therefore, the observations are assumed to be not only of local or regional interest but they appear to be of general relevance to SAR fading tests. However, with respect to the likely varying temperatures during IRSL readout of the fading dose administered in the laboratory, the observations are at least partly owed to the promptly measured test dose for normalizing the preceding (fading) dose. This is in contrast to classical multiple aliquot additive (MAA) measurements in which preheating may be replaced by long storage of a sample after laboratory irradiation and in which fading tests may be designed to also correct for possibly (slightly) changing IRSL readout temperatures at different delay times. Thus, the observations are at least partly SAR-immanent.

G-value determination of the Fricke dosemeter for 50 kvp x-rays

1969 ◽  
Vol 14 (1) ◽  
pp. 61-71 ◽  
Author(s):  
Janet Geisselsoder ◽  
C J Karzmark
Keyword(s):  
X Rays ◽  
Value Determination ◽  
G Value

Penentuan Metode Intensitas Hujan Berdasarkan Karakteristik Hujan dari Stasiun Pengamat Hujan Disekitar Kecamatan Karawang Timur

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Melisa Permatasari ◽  
M. Candra Nugraha ◽  
Etih Hartati
Keyword(s):  
Drainage System ◽  
Daily Rainfall ◽  
Intensity Analysis ◽  
Rain Intensity ◽  
Rainy Period ◽  
Discharge Plan ◽  
Calculation Results ◽  
Value Determination ◽  
Maximum Daily Rainfall ◽  
Method Approach

<p>The rain intensity is the high rainfall in unit of time. The length of rain will be reversed by the amount rain intensity. The shorter time the rain lasts, the greater of the intensity and re-period of its rain. The value of rain intensity is required to calculate the flood discharge plan on the drainage system planning area in East Karawang district. Determining the value rain intensity is required the maximum daily rainfall data obtained from the main observer stations in the Plawad station planning area. The method of determination rain intensity analysis can be done with three methods: Van Breen, Bell Tanimoto and Hasper der Weduwen. Selected method is based on the smallest deviation value. Determination deviation value is determined by comparing rain intensity value of Van Breen method, Bell Tanimoto, Hasper der Weduwen. By comparing rain intensity value of the Van Breen method, Bell Tanimoto, Hasper der Weduwen with the results of calculating three methods through the method approach Talbot, Sherman and Ishiguro. Calculation results show that the method of rain has smallest deviation standard is method Van Breen with Talbot approach for rainy period (PUH) 2, 5, 10, 25, 50 and 100 years.</p>

VALUE-SEMANTIC ECONOMY

ASJ. ◽  
2020 ◽  
Vol 1 (40) ◽  
pp. 53-57
Author(s):  
A.V. Kurbatov A.V., ◽  
L.A. Kurbatova
Keyword(s):  
Human Capital ◽  
High Efficiency ◽  
Human Capital Development ◽  
Capital Theory ◽  
The Sustainable Development ◽  
External Resources ◽  
Internal Resources ◽  
Value Determination ◽  
High Dynamics ◽  
Capital Development

The continuing build-up in the speed of deepening of the global economic crisis, driven by just as fast drop in quantity of the external resources calculated per inhabitant of our planet, forces us to refer to internal resources in order to prevent the irreversible losses, to overcome the crisis and ensure the sustainable development. Beginning from the second half of the 20-th century, the hopes for efficient deployment of internal resources have been laid on the development of the human-capital theory. However, despite the intensive change in perception of the very concept of "human capital" and a wide scope of innovative models of its practical application, aimed at bringing the economy out of stagnation, the desired outcome is not achieved. The trend of transferring of the bulk of investments to human capital, at the expense of the share of investments spent on increased production, has proved insufficient. The analysis of causes of ultra-high risks of investments in increase of human capital has helped to determine that the models, which are used currently, do not take into account some of the fundamental patterns, which ensure the high efficiency of investment in human capital. Most of the models are based on application of the methods of situational governance, which, at best, have a short-term positive effect. This trend results from the insufficient awareness of managers of the fundamental patterns of human capital development, which deprives the investors of the possibility to benefit from the optimal combination of the situational governance with relevant long-term programs, which can steadily increase human capital. The researches of the fundamental patterns of human capital development have shown, that the main factor for achieving the high efficiency of investment in human capital is the correct organization of the processes of value determination of the subjects of economic activity and the transition from the value determination to value-semantic determination, thus ensuring guaranteed attainment of goals along with high dynamics of resources. The work presented here is dedicated to the method of managing the quality of human capital, which is hereafter referred to as value-semantic economy.

Temperature Dependent Line-Shape of the Silicon Dangling Bond EPR-Resonance in Polycrystalline Silicon

1996 ◽  
Vol 452 ◽  
Author(s):  
N. H. Nickel ◽  
E. A. Schiff
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Polycrystalline Silicon ◽  
Room Temperature ◽  
Dangling Bond ◽  
Temperature Dependent ◽  
Paramagnetic Resonance ◽  
Temperature Electron ◽  
Motional Narrowing ◽  
G Value ◽  
Electron Paramagnetic

AbstractThe temperature dependence of the silicon dangling-bond resonance in polycrystalline (poly-Si) and amorphous silicon (a-Si:H) was measured. At room temperature, electron paramagnetic resonance (EPR) measurements reveal an isotropie g-value of 2.0055 and a line width of 6.5 and 6.1 G for Si dangling-bonds in a-Si:H and poly-Si, respectively. In both materials spin density and g-value are independent of temperature. While in a-Si:H the width of the resonance did not change with temperature, poly-Si exhibits a remarkable T dependence of ΔHpp. In unpassivated poly-Si a pronounced decrease of ΔHpp is observed for temperatures above 300 K. At 384 K ΔHpp reaches a minimum of 5.1 G, then increases to 6.1 G at 460 K, and eventually decreases to 4.6 G at 530 K. In hydrogenated poly-Si ΔHpp decreases monotonically above 425 K. The decrease of ΔHpp is attributed to electron hopping causing motional narrowing. An average hopping distance of 15 and 17.5 Å was estimated for unhydrogenated and H passivated poly-Si, respectively.

scholarly journals Unusual enhancement of ~ 30 MeV proton flux in an ICME sheath region

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Mitsuo Oka ◽  
Takahiro Obara ◽  
Nariaki V. Nitta ◽  
Seiji Yashiro ◽  
Daikou Shiota ◽  
...  
Keyword(s):  
Shock Front ◽  
Energetic Particle ◽  
Leading Edge ◽  
Solar Energetic Particle ◽  
Interplanetary Shock ◽  
Proton Event ◽  
Sheath Region ◽  
Time Profiles ◽  
Energetic Particle Flux ◽  
Mev Protons

AbstractIn gradual Solar Energetic Particle (SEP) events, shock waves driven by coronal mass ejections (CMEs) play a major role in accelerating particles, and the energetic particle flux enhances substantially when the shock front passes by the observer. Such enhancements are historically referred to as Energetic Storm Particle (ESP) events, but it remains unclear why ESP time profiles vary significantly from event to event. In some cases, energetic protons are not even clearly associated with shocks. Here, we report an unusual, short-duration proton event detected on 5 June 2011 in the compressed sheath region bounded by an interplanetary shock and the leading edge of the interplanetary CME (or ICME) that was driving the shock. While < 10 MeV protons were detected already at the shock front, the higher-energy (> 30 MeV) protons were detected about four hours after the shock arrival, apparently correlated with a turbulent magnetic cavity embedded in the ICME sheath region.

SPALLATION YIELDS FROM HIGH ENERGY PROTON BOMBARDMENT OF HEAVY ELEMENTS

1957 ◽  
Vol 35 (1) ◽  
pp. 21-37 ◽  
Author(s):  
J. D. Jackson
Keyword(s):  
Cross Sections ◽  
High Energy ◽  
Heavy Elements ◽  
Collective Effects ◽  
Comparison With Experiment ◽  
Energy Proton ◽  
Stringent Test ◽  
Neutron Evaporation ◽  
Nuclear Processes ◽  
Mev Protons

The Monte Carlo calculations of McManus and Sharp (unpublished) for the prompt nuclear processes occurring upon bombardment of heavy elements by 400 Mev. protons are combined with a description of the subsequent neutron evaporation to determine spallation cross sections for comparison with experiment. The model employed is a schematic one which suppresses the detailed characteristics of individual nuclei, but gives the over-all behavior to be expected. Many-particle and collective effects such as alpha particle emission and fission are ignored. The computed cross sections are presented in a variety of different graphical forms which illustrate quantitatively the qualitative picture of high energy reactions first given by Serber (1947). The calculations are in general agreement with existing data when fission is not an important effect, but the agreement does not imply a very stringent test of the various features of the model.

scholarly journals Factors Affecting the Dependency of Shear Strain of LRB and SHDR: Experimental Study

Actuators ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 98
Author(s):  
Chao-Yong Shen ◽  
Xiang-Yun Huang ◽  
Yang-Yang Chen ◽  
Yu-Hong Ma
Keyword(s):  
Experimental Study ◽  
Low Temperature ◽  
Shear Strain ◽  
Loading Frequency ◽  
Loading Test ◽  
Characteristic Strength ◽  
Rubber Bearing ◽  
Dominant Feature ◽  
Loading Sequence ◽  
G Value

In this research we conducted a sensitivity experimental study where we explored the dependency of the shear strain on the seismic properties of bearings, namely lead rubber bearing (LRB) and super high damping rubber bearing (SHDR). The factors studied were vertical pressure, temperature, shear modulus of the inner rubber (G value), loading frequency, and loading sequence. Six specimens were adopted, i.e., three LRBs and three SHDR bearings. A series of test plans were designed. The seismic characteristics of the bearings were captured through a cyclic loading test, which included post-yield stiffness, characteristic strength, area of a single cycle of the hysteretic loop, equivalent stiffness, and equivalent damping ratio. A whole analysis of variances was then conducted. At the same time, to explore certain phenomena caused by the factors, an extended discussion was carried out. Test results showed that the temperature is the most dominant feature, whereas the G value is the least contributing factor, with the effect of the loading frequency and the loading sequence found between these two. The increment of the post-yielded stiffness for LRB from 100% to 25% is a significant reduction from a low temperature to high one. The slope of the characteristic strength versus the shear strain for LRB under high temperature is larger than the one under low temperature.

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