Pairwise combination of methods of detecting radiation sources

2008 ◽  
Vol 51 (8) ◽  
pp. 913-921 ◽  
Author(s):  
V. M. Kirillov
Author(s):  
G. Lehmpfuhl ◽  
P. J. Smith

Specimens being observed with electron-beam instruments are subject to contamination, which is due to polymerization of hydrocarbon molecules by the beam. This effect becomes more important as the size of the beam is reduced. In convergent-beam studies with a beam diameter of 100 Å, contamination was observed to grow on samples at very high rates. Within a few seconds needles began forming under the beam on both the top and the underside of the sample, at growth rates of 400-500 Å/s, severely limiting the time available for observation. Such contamination could cause serious difficulty in examining a sample with the new scanning transmission electron microscopes, in which the beam is focused to a few angstroms.We have been able to reduce the rate of contamination buildup by a combination of methods: placing an anticontamination cold trap in the sample region, preheating the sample before observation, and irradiating the sample with a large beam before observing it with a small beam.


2006 ◽  
Vol 133 ◽  
pp. 1173-1175
Author(s):  
C. A. Back ◽  
J. F. Seely ◽  
J. L. Weaver ◽  
U. Feldman ◽  
R. Tommasini ◽  
...  
Keyword(s):  

SinkrOn ◽  
2020 ◽  
Vol 4 (2) ◽  
pp. 151
Author(s):  
Rinaldi Setiawan ◽  
Arini Arini ◽  
Luh Kesuma Wardhani

The number of micro, small and medium enterprises (MSMEs) in the field of screen printing and convection that use websites in marketing is one of them CV. Ini Sablon. but in the production process there are obstacles in working on orders that come to be done first in accordance with predetermined criteria, namely deadlines, number of orders, design, profit, and availability of goods. The use of Decision Support System (DSS) aims to provide recommendations to owners of screen printing companies. This study uses the SMART method to weight the criteria and the TOPSIS method for product selection. This system is built using the PHP programming language and MySQL database. The results of the study were a screen printing production priority website with the best final value of 0.62 and the worst final value of 0.35 with the level of accuracy between manual and system calculations reaching 100%. In this study the criteria cannot be updated, it is expected that further research criteria can be updated and use a combination of methods that have not been done.


2020 ◽  
Vol 23 (1) ◽  
pp. 66-71
Author(s):  
E. A. Gurnevich ◽  
I. V. Moroz

The Smith-Purcell radiation of a charged particle moving in a periodic structure is analysed theoretically. The considered structure consists of two planar diffraction gratings with different periods which are formed by parallel conducting wires. The analytical expression for the spectral-angular distribution of radiation is obtained. It is shown that the angular distribution of radiation can be made narrower by using two gratings instead of one, and radiation intensity can be manipulated by parallel relative shift of gratings. The obtained results are of great importance for the research and development of high power radiation sources based on volume free-electron lasers.


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.


Author(s):  
Nataliia Vdovenko ◽  
Maryna Pavlenko ◽  
Elena Hryniuk

The purpose of the article it consists in the substantiation of innovation and investment principles of competitive development of fisheries and aquaculture in order to effectively conduct business in modern economic conditions and to comply with technological parameters of production, introduce innovations in production, and economical attitude to fish and water resources. Methodology research consists in using a combination of methods: economic-statistical, monographic, systemic, economic-mathematical, abstract-logical and others. The scientific novelty the re- sults obtained include the introduction of innovative, economically viable and competitive production technologies based on a scientific approach to organizing an aquaculture business, namely the ability to quickly and efficiently respond to external challenges, find a way out of a critical situation and correctly adjust production plans in accordance with changes in market conditions. Conclusions. Substantially modern principles of the effective functioning of fisheries in order to ensure competitive activity. Regulatory tools are proposed to ensure the profitability of the aquaculture business, which include attracting in- vestments for the acquisition of capital goods, training specialists and constantly improving their skills, and ensuring efficient fisheries production in an innovative economy.


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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