scholarly journals Radon signals in geological (natural) geogas and in a simultaneous enhanced confined mode simulation experiment

2018 ◽  
Vol 474 (2216) ◽  
pp. 20170787
Author(s):  
Gideon Steinitz ◽  
Peter Kotlarsky ◽  
Oksana Piatibratova
Keyword(s):  
Gamma Radiation ◽  
Simulation Experiment ◽  
Experimental System ◽  
Geophysical Research ◽  
Variation Pattern ◽  
Stable Temperature ◽  
External Driver ◽  
Lead Shielding ◽  
Periodic Components ◽  
Typical Variation

An enhanced confined mode (ECM) radon simulation experiment, tested in the laboratory in Jerusalem, was relocated to a subsurface geophysical observatory located 400 km apart, at a depth of 150 m and with a stable temperature. Five gamma sensors are placed around the ECM canister and lead shielding minimizes the influence of natural local gamma radiation. Simultaneous measurement of the geological radon and from radon in the ECM system indicates that the temporal variation of gamma radiation from radon in the ECM system contains annual, multi-day and daily signals, that correspond to signals in the local geological radon. This implies that a common external driver influences the radiation pattern of the geological radon and from radon inside the ECM canister. Once activated at BGO the typical variation pattern of the experimental system occurring in the laboratory changed to that occurring at the observatory. This is interpreted to indicate that the overall style of the temporal patterns of radiation from radon is site dependent. The outcome of this investigation conforms and further substantiates the recent suggestion that a component in solar radiation is driving the annual and daily periodic components in the variation of radon. New geophysical research potential is indicated.

scholarly journals The gamma radiation shielding effectiveness of textured steel yarn based fabrics

2018 ◽  
Vol 69 (01) ◽  
pp. 44-49
Author(s):  
ÖZDEMIR HAKAN ◽  
CAMGÖZ BERKAY
Keyword(s):  
Gamma Radiation ◽  
Structural Characteristics ◽  
Woven Fabrics ◽  
Radiation Shielding ◽  
Weft Yarn ◽  
Personal Protection ◽  
Shielding Effectiveness ◽  
X Ray ◽  
Lead Shielding ◽  
Shielding Material

Lead aprons that are lead-shielding products are generally used for personal protection of physicians and patients from X-ray (gamma) radiation during medical operations; lead has environmental disadvantages, with high toxicity, though. Therefore, the aim of this research was to produce an environmentally friendly and flexible textile-based radiation shielding material. In this work, 2/2 twill, 3/1 twill, Herringbone, Whipcord, which are twill derivatives, Barathea and Crêpe woven fabrics, which are sateen derivatives, woven with textured steel yarns, which have soft feeling and flexibility, and gamma radiation shielding effectiveness of these fabrics were investigated and were not studied in the references. The effects of fabric structural characteristics such as weave, conductive weft yarn density, fabric thickness and porosity on these properties were analysed graphically and statistically. It is observed that with the biggest thicknesses and lowest porosities, Barathea and Crêpe woven fabrics performed better gamma radiation shielding performance than other woven fabrics. The samples F1 and E1, woven with Barathea and Crêpe weave, have the highest gamma radiation shielding effectiveness, thanks to the highest fabric thicknesses and lowest porosities. In addition, the increases of textured steel yarn density improved the gamma radiation shielding effectiveness of woven fabrics.

Mechanical Simulation Experiment of Coiled Tubing in Wells

2012 ◽  
Vol 594-597 ◽  
pp. 2460-2463
Author(s):  
Feng Guan ◽  
Wei Guo Ma ◽  
Xian Zhong Yi
Keyword(s):  
Operating Systems ◽  
Structural Design ◽  
Test Bench ◽  
Simulation Experiment ◽  
Experimental System ◽  
Functional Requirements ◽  
Coiled Tubing ◽  
Function Module ◽  
Helical Buckling ◽  
Actual Depth

Coiled tubing operating systems have complex underground loading, by related research, we have got the solution about actual depth which the coiled tubing goes into well, and we also have got the solution about the buckling and lock-up of coiled tubing. The reasonable overall experiment scheme is put forward according to the related functional requirements, the appropriate geometric parameters and dynamic parameters of the experimental system is determined, the function module analysis and structural design of the test bench is carried on. The experimental phenomena about buckling and helical buckling lock-up are analyzed, and the conditions of helical buckling lock-up are put forward. This experiment has provided the basis for the analysis of mechanical behavior of coiled tubing in wells.

Effects of sterilization modes on the mechanical strengths of plaster of paris implants

1989 ◽  
Vol 47 ◽  
pp. 890-891
Author(s):  
K. Cowden ◽  
B. Giammara ◽  
T. Devine ◽  
J. Hanker
Keyword(s):  
Gamma Radiation ◽  
Calcium Sulfate ◽  
Significant Loss ◽  
Potassium Sulfate ◽  
Limiting Factors ◽  
Radiation Sterilization ◽  
Plaster Of Paris ◽  
Hardness Tester ◽  
Dry Heat ◽  
Calcium Sulfate Hemihydrate

Plaster of Paris (calcium sulfate hemihydrate, CaSO4. ½ H2O) has been used as a biomedical implant material since 1892. One of the primary limiting factors of these implants is their mechanical properties. These materials have low compressive and tensile strengths when compared to normal bone. These are important limiting factors where large biomechanical forces exist. Previous work has suggested that sterilization techniques could affect the implant’s strength. A study of plaster of Paris implant mechanical and physical properties to find optimum sterilization techniques therefore, could lead to a significant increase in their application and promise for future use as hard tissue prosthetic materials.USG Medical Grade Calcium Sulfate Hemihydrate Types A, A-1 and B, were sterilized by dry heat and by gamma radiation. Types A and B were additionally sterilized with and without the setting agent potassium sulfate (K2SO4). The plaster mixtures were then moistened with a minimum amount of water and formed into disks (.339 in. diameter x .053 in. deep) in polyethylene molds with a microspatula. After drying, the disks were fractured with a Stokes Hardness Tester. The compressive strengths of the disks were obtained directly from the hardness tester. Values for the maximum tensile strengths σo were then calculated: where (P = applied compression, D = disk diameter, and t = disk thickness). Plaster disks (types A and B) that contained no setting agent showed a significant loss in strength with either dry heat or gamma radiation sterilization. Those that contained potassium sulfate (K2SO4) did not show a significant loss in strength with either sterilization technique. In all comparisons (with and without K2SO4 and with either dry heat or gamma radiation sterilization) the type B plaster had higher compressive and tensile strengths than that of the type A plaster. The type A-1 plaster however, which is specially modified for accelerated setting, was comparable to that of type B with K2SO4 in both compressive and tensile strength (Table 1).

Detecting Random Responses in a Personality Scale Using IRT-Based Person-Fit Indices

2019 ◽  
Vol 35 (1) ◽  
pp. 126-136 ◽  
Author(s):  
Tour Liu ◽  
Tian Lan ◽  
Tao Xin
Keyword(s):  
Experimental System ◽  
Real Data ◽  
Fit Indices ◽  
Random Response ◽  
Person Fit ◽  
Index Method ◽  
Single Person ◽  
Person Fit Index ◽  
Random Responses ◽  
Response Behaviors

Abstract. Random response is a very common aberrant response behavior in personality tests and may negatively affect the reliability, validity, or other analytical aspects of psychological assessment. Typically, researchers use a single person-fit index to identify random responses. This study recommends a three-step person-fit analysis procedure. Unlike the typical single person-fit methods, the three-step procedure identifies both global misfit and local misfit individuals using different person-fit indices. This procedure was able to identify more local misfit individuals than single-index method, and a graphical method was used to visualize those particular items in which random response behaviors appear. This method may be useful to researchers in that it will provide them with more information about response behaviors, allowing better evaluation of scale administration and development of more plausible explanations. Real data were used in this study instead of simulation data. In order to create real random responses, an experimental test administration was designed. Four different random response samples were produced using this experimental system.

Use of the comet assay to measure DNA damage in cells exposed to photosensitizers and gamma radiation

1999 ◽  
Vol 96 (1) ◽  
pp. 143-146 ◽  
Author(s):  
J.-P. Pouget ◽  
J.-L. Ravanat ◽  
T. Douki ◽  
M.-J. Richard ◽  
J. Cadet
Keyword(s):  
Dna Damage ◽  
Comet Assay ◽  
Gamma Radiation ◽  
In Cells

Antifibrinolytic Action of the Anticoagulant Split Product of Fibrinogen

1968 ◽  
Vol 19 (03/04) ◽  
pp. 526-532 ◽  
Author(s):  
L. B Nanninga ◽  
M. M Guest
Keyword(s):  
Experimental System ◽  
New Method ◽  
System A ◽  
Fibrinogenolytic Activity

SummaryThe purified anticoagulant split product of fibrinogen has antifibrinolytic and anti-fibrinogenolytic activity. This was investigated by lysis times of fibrin and by the rate of disappearance of fibrinogen in plasma and in a purified system. A new method was used to measure fibrinogenolytic activity. In the experimental system which we have used no indication of additional breakdown of the anticoagulant split product in the presence of fibrinolysin was obtained.

National primary standard of air kerma, air kerma rate, exposure, exposure rate and energy flux for X-rays and gamma radiation GET 8-2019

2020 ◽  
pp. 8-12
Author(s):  
Alexandr V. Oborin ◽  
Anna Y. Villevalde ◽  
Sergey G. Trofimchuk
Keyword(s):  
Gamma Radiation ◽  
Energy Flux ◽  
Primary Standard ◽  
Average Energy ◽  
Ion Pair ◽  
X Rays ◽  
Exposure Rate ◽  
Ionization Chambers ◽  
Air Kerma ◽  
Air Kerma Rate

The results of development of the national primary standard of air kerma, air kerma rate, exposure, exposure rate and energy flux for X-rays and gamma radiation GET 8-2011 in 2019 are presented according to the recommendations of the ICRU Report No. 90 “Key Data for Ionizing-Radiation Dosimetry: Measurement Standards and Applications”. The following changes are made to the equations for the units determination with the standard: in the field of X-rays, new correction coefficients of the free-air ionization chambers are introduced and the relative standard uncertainty of the average energy to create an ion pair in air is changed; in the field of gamma radiation, the product of the average energy to create an ion pair in air and the electron stopping-power graphite to air ratio for the cavity ionization chambers is changed. More accurate values of the units reproduced by GET 8-2019 are obtained and new metrological characteristics of the standard are stated.

An experimental system on heart resistance by split dose hyperthermia

1983 ◽  
Vol 19 (3) ◽  
pp. 475
Author(s):  
M H Yoo ◽  
K J Lee ◽  
C S Rhee
Keyword(s):  
Experimental System ◽  
Split Dose
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