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361.
The mass energy absorption coefficient(μ_(en)/p),effective atomic number(Z_(PEA)_(eff)),and electron density(N_(PEA)_(eff))of some biomolecules with potential application in radiation dosimetry were calculated for their photon energy absorption(PEA)in the energy region of 1-20 MeV.It was noticed that the values of μ_(en)/ρ,Z_(PEA)_(eff),and N_(PEA)_(eff) vary with the energy and composition of the biomolecules.The results for Z_(PEA)_(eff) were compared with effective atomic numbers(Z_(PI)_(eff))owing to the photon interaction(PI).Significant differences were noted between Z_(PEA)_(eff) and Z_(PI)_(eff) in the energy region of 10-150 keV for all of the biomolecules involved.A maximum difference of 45.36% was observed at 50 keV for creatinine hydrochloride.Moreover,the studied attenuation parameters were found to be sharply affected at the K-absorption edge of relatively high-Z elements present in the biomolecules.  相似文献   
362.
This study reports the results of a preliminary study of manufacturing aluminum–potassium feldspar metal matrix composites including its castability and mechanical properties. The material was composed considering 0.25 %, 0.5 %, and 0.75 % additive ratios to examine the impact of the amount of potassium feldspar on the material and mechanical properties of the manufactured aluminum metal matrix composite material. Aluminum alloy (A356) was utilized as the matrix of the composition. The composite material was manufactured by the stir casting technique. The modulus of elasticity, yield strength, tensile strength, elongation, density, and quality index of the material parameters was taken into account to determine the materials′ practicality. The preliminary results indicated that potassium feldspar is a promising mineral to be utilized as an additive for aluminum metal matrix composites since it has a positive impact on mechanical properties. By optimizing the casting parameters, the positive aspects of the potassium feldspar may make the material more practical to be utilized in vast engineering applications.  相似文献   
363.
This article presents the mutual diffusion coefficients of a carbon dioxide–ionic liquid, [bmim][PF6], system at temperatures of 313.15 and 323.15 K and pressures of 5 and 8 MPa. In order to estimate the diffusion coefficients, we have carried out experiments to find time-dependent carbon dioxide solubilities in the ionic liquid and then fit a transport model to the data. In a system containing high pressure carbon dioxide and ionic liquid, carbon dioxide dissolves in the liquid until its equilibrium mole fraction is reached. During this process, the position of the liquid–vapour interface and the density of the liquid phase change. To account for the variation in liquid density, an equation fit to the experimental density data is included in the transport model. To track the moving interface, the volume-of-fluid method is used. The diffusivities at dilute concentration and at thermodynamic phase equilibrium are determined and compared with the literature values and those obtained from correlations.  相似文献   
364.
Measurement models in civil engineering. A review The research project “‘Last Witnesses’ Measurement Models in Civil Engineering – Scientific Significance and Preservation” was funded as part of the priority program 2255 “Construction as Cultural Heritage” of the German Research Foundation (DFG) and consists of three sub-projects divided between the University of Innsbruck, the Karlsruhe University of Applied Sciences and the Technical University of Munich. The project aimed to locate the last surviving measurement models in German-speaking countries, document them, classify them in terms of construction history, digitise them and evaluate their state of conservation. This report is intended to provide an overview of the initial situation, the approaches, the difficulties and the results and findings achieved in the project.  相似文献   
365.
We aimed to enhance the magnetic force efficiency of Maglev systems without increasing total weight. For this aim, we divided YBCO bulks into three slices horizontally to utilize the YBCO-permanent magnetic guideway (PMG) interaction surface as much as possible. We used whole YBCO above PMGs with different magnetic pole directions (PMG-A and PMG-B) in two lying positions of transversal and longitudinal and investigated levitation and guidance force performances. It is determined that levitation and guidance forces by using YBCO in transversal lying mode are bigger compared to the longitudinal mode. For sliced YBCO, the maximum levitation force increased by 69% and 78%, while the guidance force enhancements are determined as 212% and 91%, compared to the whole YBCO above PMG-A and PMG-B, respectively. The levitation and guidance force density with respect to the total mass of unit a set of slices YBCO increased by 92% and 106%, respectively, compared to the whole YBCO above PMG-B in transversal mode. Since the higher levitation force and the lower total weight of the onboard unit are important parameters in point of the energy efficiency in Maglev and other levitation applications, the result of this study supplies useful data for the engineers and industrial partners.  相似文献   
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