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1.
Marija argonja Darko Mekterovi Paula
urga Jagoda Ravli‐Gulan Iva Bogdanovi Radovi Gordana
auhar 《X射线光谱测定》2021,50(1):68-79
During metal welding and cutting, large amounts of particulate matter (PM) are produced that might represent a significant health risk for the exposed workers. In the present pilot study, we performed an elemental analysis of fine PM collected in a metal workshop. Also, elemental analysis of the hair and nail samples collected from workers exposed to the workshop dust and control group was done. Concentrations of 15 elements in PM were measured with X‐Ray Fluorescence (XRF) and Particle Induced X‐ray Emission (PIXE), whereas inductively coupled plasma mass spectrometry (ICP‐MS) was used to determine 12 elements in hair and nail samples. Mean 8‐hr concentrations of PM2.5, Fe, and Mn in the vicinity of welders were up to 1803, 860, and 30 μg/m3, respectively, whereas in the nearby city, daily PM2.5 concentrations are on average 11 μg/m3. We found that several elements, especially Fe and Mn, had substantially higher concentrations in hair and nail samples of exposed workers than in the control group, which indicates the accumulation of metals in workers' tissues, although limit values were not exceeded. 相似文献
2.
Lipatnikova Ya. D. Valuiskaya L. A. Solov’eva Yu. V. Cherepanov D. N. Zgolich M. V. Belov N. N. Starenchenko V. A. 《Russian Physics Journal》2021,64(3):371-375
Russian Physics Journal - The paper presents mathematical simulation of localized plastic deformation of metal-intermetallic laminated composites after equal channel angular pressing. Deformation... 相似文献
3.
Journal of Applied Mechanics and Technical Physics - The accuracy of numerical calculations of the dynamics of vortex filaments is estimated via the cutoff method using the example of the motion of... 相似文献
4.
Nonlinear Dynamics - The hybrid neural model provides a computationally effective and biophysics-based neuron behavior model, which maintains its simplicity by incorporating the dynamics... 相似文献
5.
In this article a coupled version of the improved divergence‐free‐condition compensated method will be proposed to simulate time‐varying geometries by direct forcing immersed boundary method. The proposed method can be seen as a quasi‐multi‐moment framework due to the fact that the momentum equations are discretized by both cell‐centered and cell‐face velocity. For simulating time‐varying geometries, a semi‐implicit iterative method is proposed for calculating the direct forcing terms. Treatments for suppressing spurious force oscillations, calculating drag/lift forces, and evaluating velocity and pressure for freshly cells will also be addressed. In order to show the applicability and accuracy, analytical as well as benchmark problems will be investigated by the present framework and compared with other numerical and experimental results. 相似文献
6.
Mokshin A. V. Khusnutdinoff R. M. Vilf Ya. Z. Galimzyanov B. N. 《Theoretical and Mathematical Physics》2021,206(2):216-235
Theoretical and Mathematical Physics - In the framework of the concept of time correlation functions, we develop a self-consistent relaxation theory of the transverse collective particle dynamics... 相似文献
7.
Zhang Tinggui Xi Ya Fei Shao-Ming 《International Journal of Theoretical Physics》2021,60(8):2909-2915
We study the Bell nonlocality of high dimensional quantum systems based on quantum entanglement. A quantitative relationship between the maximal expectation value B of Bell operators and the quantum entanglement concurrence C is obtained for even dimension pure states, with the upper and lower bounds of B governed by C.
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Turdybekov K. M. Nurkenov O. A. Seilkhanov T. M. Fazylov S. D. Turdybekova Ya. G. Kudusov A. S. 《Journal of Structural Chemistry》2022,63(6):944-950
Journal of Structural Chemistry - N-cyanomethylanabasine is prepared with an yield of 70% by the interaction of the alkaloid anabasine with glyconitrile. It is shown that the highest yield of the... 相似文献