Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "density of surface" wg kryterium: Temat


Wyświetlanie 1-6 z 6
Tytuł:
Volumes determination in terms of various data density and surface diversity
Autorzy:
Sokol, S.
Bajtala, M.
Lipták, M.
Brunčák, P.
Powiązania:
https://bibliotekanauki.pl/articles/91995.pdf
Data publikacji:
2014
Wydawca:
Główny Instytut Górnictwa
Tematy:
theoretical surface
terrestrial laser scanning
volume calculation
density of surface
diversity of surface
powierzchnia teoretyczna
skanowanie laserowe naziemne
obliczanie objętości
gęstość powierzchni
różnorodność powierzchni
Opis:
Purpose The aim of this paper is to assess the impact of input data density and diversity on surfaces obtained using the terrestrial laser scanning (TLS) method for creating digital elevation model (DEM). For this we can use several approaches, while we have chosen an intermediary parameter – volume calculation, which is in practice the most frequently requested requirement from surveyors. Methods Precise terrestrial measurement and terrestrial laser scanning were used to ensure that detailed knowledge about the surface and volumes of two piles of earth and a stone pit in comparison with theoretical defined surfaces was obtained. Results Mathematically defined surfaces generally have smooth shapes, and thus the effect of different density on the input data is less apparent in the final comparison of volumes. In our case the results for most of the different interpolation methods and the different density of the input data was less than 0.5%. From the experimental measurements of the two earth bodies and the quarry, which have an irregular shape with unsmooth surfaces, we can only test the relative precision of the calculated volumes to the data with the highest density. Experimental measurements in the area of the quarry, where the scanned surface was uneven and considerably different in height, confirmed the assumption that a vastly irregular surface should exhibit more significant variations than a smooth surface, but for the nearest neighbour method relative errors under 1% were achieved. Practical implications According to the results from the analysis above, the lower density of input data we have, the lower the precision of calculating volumes we can assume, but it is interesting that we did not achieved significantly worse results with strongly irregular surfaces compared to a less irregular surface. Originality/ value The input values for the analysis of theoretically defined surfaces were obtained by the calculation of integral calculus and earth-moving bodies and quarry from an experimental measurement terrestrial laser scanning method and were used in Slovakia for the first time.
Źródło:
Journal of Sustainable Mining; 2014, 13, 4; 23-27
2300-1364
2300-3960
Pojawia się w:
Journal of Sustainable Mining
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A first-principle study of the effect of Fe/Al impurity defects on the surface wettability of dolomite
Autorzy:
Chen, Hong
Ao, Xianquan
Cao, Yang
Li, Cuiqin
Jiang, Chunyan
Powiązania:
https://bibliotekanauki.pl/articles/2146916.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
density functional theory
phosphate rock flotation
dolomite
surface wettability
density of states
Opis:
The presence of Fe and Al atoms in large quantities in phosphate ores can significantly affect the surface properties of the minerals during flotation. In this study, the effects of Fe/Al impurities on the adsorption of H2O molecules on dolomite, including the density of states (DOS), Mulliken bond group values, and charge groups, were investigated and the adsorption energy was analyzed using density functional theory. The results show that the adsorption of H2O molecules on perfect and Fe/Al-substituted dolomites is weak chemisorption, and the Fe and Al impurities weaken and enhance the adsorption capacity of H2O molecules, respectively. Therefore, the hydrophilicity of the dolomite surface increases in the following order: Fe-substituted dolomite < perfect dolomite < Al-substituted dolomite. The Mulliken charge and bond group analysis shows that the adsorption of H2O molecules on dolomite is primarily through the interaction between Ow and Ca atoms, where the d orbitals of Ca atoms provide charges for Ow atoms to form ionic bonds, which related to the poor electronegativity of Ca atoms and their weak valence electron binding ability. The DOS analysis shows that, during the adsorption of H2O molecules on dolomite, Mg and Al atoms have less influence on the dolomite surface, whereas Fe and Ca atoms undergo competitive adsorption, which inhibits the interaction between Ca atoms and H2O molecules on the dolomite surface.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 4; art. no. 150702
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Zinc on the Surface Tension, Density and Molar Volume of (Ag-Sn)eut +Zn Liquid Alloys
Autorzy:
Gąsior, W.
Pstruś, J.
Moser, Z.
Powiązania:
https://bibliotekanauki.pl/articles/355603.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
influence of zinc
surface tension
density
molar volume alloys
Opis:
The dilatometric and maximum bubble pressure methods were applied for the measurements of the density and surface tension of liquid (Ag-Sn)eut +Zn lead-free solders. The experiments were carried out in the temperature range from 515 to 1223 K for the alloys of the zinc concentration equaling 0.01, 0.02, 0.04, 0.05, 0.1 and 0.2 of the mole fraction. It was found that the temperature dependence of both the density and the surface tension could be thought as linear, so they were interpreted by straight line equations. The experimental data of the molar volume of the investigated alloys were described by the polynomial dependent on the composition and temperature. Calculations of the surface tension by Butler’s equation were conducted and confronted with the experimental data. Some significant deviations between the experimental and the calculated surface tension were observed. They reached almost 40 mNm-1. The observed changes of the density and surface tension caused by the zinc addition to the Ag-Sn eutectic were discussed with the consideration of the thermodynamic properties and the influence of a small quantity of impurities in a protective gas atmosphere.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 361-368
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Small high density lipoprotein subclasses: some of their physico-chemical properties and stability in solution.
Autorzy:
Atmeh, Ragheb
Abd Elrazeq, Issa
Powiązania:
https://bibliotekanauki.pl/articles/1041440.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
small high density lipoproteins
diffusion coefficient
surface charge
molecular shape
coefficient of friction
stability
Opis:
Small high density lipoproteins (SHDL) contribute to the protection from atherosclerosis, but detailed information about their properties is not available yet. We isolated four of the smallest HDL subclasses that contain apoA-I alone, the small lipoprotein A-I (SLpAI), by their separation on gradient polyacrylamide gel followed by electroelution. Their physico-chemical properties were calculated from their displacement in non-denaturing gradient polyacrylamide gel under the effect of electrical potential. The properties are: Stokes' radii 2.96-3.56 nm; molecular masses 42-70 kDa; net negative charge 7.2-13.5; surface charge densities 3139-4069 -esu∙˙cm^(-2); surface potentials 10.6-15.7 -mV; coefficients of friction 5.74-6.90 × 10-8 g∙˙s^(-1); and diffusion coefficients 5.76-6.94 7× 10-7 cm^2∙˙s^(-1). We found that these particles were of low stability as they underwent molecular transformation into larger particles on storage. The estimated dimensions of these particles do not support ellipsoidal shape, therefore, the most probable shape is spherical; consequently, their hydrated characteristics were estimated. We conclude that these particles have high values of negative surface charge and diffusion coefficients, and are of low stability. Their small Stokes' radii were similar to each other and they are spherical and highly hydrated.
Źródło:
Acta Biochimica Polonica; 2005, 52, 2; 515-525
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of gypsum share on selected properties of high-density wetformed fiberboard
Autorzy:
Goliaszewska, Ada
Kowaluk, Grzegorz
Powiązania:
https://bibliotekanauki.pl/articles/2204037.pdf
Data publikacji:
2019
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
hardboard
fibreboard
wet-formed fibreboard
gypsum
density profile
contact angle
modulus
of elasticity in bending
bending strength
surface water absorption
Opis:
Influence of gypsum share on selected properties of high-density wetformed fiberboard
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology; 2019, 106; 22--30
1898-5912
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effective energy integral functionals for thin films with three dimensional bending moment in the Orlicz-Sobolev space setting
Autorzy:
Laskowski, Włodzimierz
Nguyen, Hong
Powiązania:
https://bibliotekanauki.pl/articles/729638.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
Γ-convergence
3D-2D dimension reduction
quasiconvex relaxation
minimizers of variational integral functionals
thin films
elastic membranes
effective energy integral functional
bulk and surface energy
equilibrium states of the film
non-power-growth-type bulk energy density
reflexive Orlicz and Orlicz-Sobolev spaces
Opis:
In this paper we consider an elastic thin film ω ⊂ ℝ² with the bending moment depending also on the third thickness variable. The effective energy functional defined on the Orlicz-Sobolev space over ω is described by Γ-convergence and 3D-2D dimension reduction techniques. Then we prove the existence of minimizers of the film energy functional. These results are proved in the case when the energy density function has the growth prescribed by an Orlicz convex function M. Here M is assumed to be non-power-growth-type and to satisfy the conditions Δ₂ and ∇₂.
Źródło:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization; 2016, 36, 1; 7-31
1509-9407
Pojawia się w:
Discussiones Mathematicae, Differential Inclusions, Control and Optimization
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-6 z 6

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies