The influence of MWCNT and hybrid ( MWCNT /nanoclay) fillers on performance of EPDM‐CIIR blends in nuclear applications: Mechanical, hydrocarbon transport, and gamma‐radiation aging characteristics

2020 ◽  
Vol 137 (42) ◽  
pp. 49271
Author(s):  
Ashok Neelesh ◽  
Sakthivel Vidhyashree ◽  
Balachandran Meera
2014 ◽  
Vol 453 (1-3) ◽  
pp. 233-238 ◽  
Author(s):  
Hsu-Sheng Tsai ◽  
Der-Sheng Chao ◽  
Ya-Hsuan Wu ◽  
Yu-Ting He ◽  
Yu-Lun Chueh ◽  
...  

Author(s):  
K. Cowden ◽  
B. Giammara ◽  
T. Devine ◽  
J. Hanker

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).


1999 ◽  
Vol 96 (1) ◽  
pp. 143-146 ◽  
Author(s):  
J.-P. Pouget ◽  
J.-L. Ravanat ◽  
T. Douki ◽  
M.-J. Richard ◽  
J. Cadet

2020 ◽  
pp. 8-12
Author(s):  
Alexandr V. Oborin ◽  
Anna Y. Villevalde ◽  
Sergey G. Trofimchuk

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.


1975 ◽  
Vol 116 (7) ◽  
pp. 517 ◽  
Author(s):  
O.F. Prilutskii ◽  
I.L. Rozental' ◽  
V.V. Usov
Keyword(s):  

1980 ◽  
Vol 132 (12) ◽  
pp. 700
Author(s):  
A.M. Gal'per ◽  
Yu.D. Kotov ◽  
B.I. Luchkov
Keyword(s):  

Author(s):  
Adam Bodіuk

The subject of the study is the mechanism for determining the fiscal fee forthe main transportation of hydrocarbon goods as a resource concept. The purposeof this article is to justify the nature and prospects of using, instead of currentrent, hydrocarbon fiscal-main income as a fiscal payment, which is brought intothe state budget by operators of the main hydrocarbon-transport system as business entities for their transportation of hydrocarbons and products of their processing through main pipelines appropriate to the economic requirements. Theresearch methodology is determined by a combination of methods: a) cognition:legal analysis (study of the regulatory framework for the use of rent); b) justification: abstract logical analysis (definition of the concepts of hydrocarbon fiscalmain income); c) generalization (substantiation of conclusions and proposals).Results of work. In the process of analyzing the regulatory legal acts that regulate the use of current annuity as payment to the budget for the main transportation of hydrocarbons, it was established that it is not a tax in the interpretationof PKU, since the essence does not meet the official definition of tax, does notmeet the accepted definition of the concept of rent. The accepted nature andmechanism of paying rent for the transportation of hydrogen resources and associated revenues of the state and users of the main hydrogen transport systemand the unpromising nature of its use as a fiscal payment are analyzed. Conclusions.It is proposed that the state pay for the territorial pumping of hydrocarbon resources according to our triple principle as hydrocarbon fiscal-main income, whichcorresponds to its essence, and accordingly change the mechanism for calculatingand depositing funds to treasury accounts. Since the funds come to the revenueside of the state budget, that is, inherently belong to state revenue. The creationof such a mechanism needs certain studies, justifications and government decisions. The same applies to land use, since the quality indicators of soils, wherethe laid pipelines are territorially different. In addition, there is a process ofchanging land for its intended purpose, for the property. The fee for movinghydrocarbon resources should be calculated depending on the type of transport,including pipelines, for a set of indicators: quantity and quality of goods, time,main tariffs and distance of its movement. The amount may be adjusted usingfactors officially established by the CMU. Since the pipelines are located in territorial lands, part of this fee should be transferred to the territorial local budgets.Theoretically, the economic use of trunk pipelines should be considered as a typeof economic environmental management. Therefore, this type of government revenue should be determined by a set of indicators, as well as taking into account the economic interests of business entities authorized by the CMU. Thus, theimplementation of our proposed fiscal payment is relevant, has scientific noveltyand promising practical significance, therefore, for state recognition it is proposedto include it in the Tax Code of Ukraine.


2018 ◽  
Vol 9 (08) ◽  
pp. 20193-20206 ◽  
Author(s):  
Md. Akhlak Bin Aziz ◽  
Md. Faisal Rahman ◽  
Md. Mahidul Haque Prodhan

The paper compares  Lead, Copper and Aluminium as gamma radiation shielding material using both experimental and simulation techniques. Cs- 137 (662KeV), Na-22 (511KeV) and Na- 22(1274KeV) were used as gamma radiation sources and a sodium iodide (NaI) detector was used to detect the radiation. Variations were noted for detected gamma count rates by changing shielding material thickness. In the experimental approach, thickness was varied by placing sheets of a particular test material one by one. For simulation, Monte Carlo n- Particle (MCNP) code version 4c was used and the geometry of the whole experimental setup was plotted in it. The results were then compared for each test material and it was found that lead is the best shielding material for gamma radiation followed by copper and aluminium.


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