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排序方式: 共有10000条查询结果,搜索用时 312 毫秒
1.
Doklady Mathematics - New properties of convex infinitely differentiable functions related to extremal problems are established. It is shown that, in a neighborhood of the solution, even if the... 相似文献
2.
Mayboroda I. O. Kolobkova E. M. Grishchenko Yu. V. Chernykh I. A. Zanaveskin M. L. Chumakov N. K. 《Crystallography Reports》2021,66(3):520-524
Crystallography Reports - The formation of β-Si3N4 for subsequent growth of AlGaN and GaN heterostructures of silicon wafers has been studied. It is established that the native oxide layer... 相似文献
3.
Liu Wen-Wen Yang Zi-Feng Fei Shao-Ming 《International Journal of Theoretical Physics》2021,60(11-12):4177-4195
International Journal of Theoretical Physics - We investigate the monogamy relations related to the concurrence, the entanglement of formation, convex-roof extended negativity, Tsallis-q... 相似文献
4.
5.
Khabensky V. B. Almjashev V. I. Granovsky V. S. Krushinov E. V. Vitol S. A. Kotova S. Yu. Gusarov V. V. 《Technical Physics》2021,66(2):221-228
Technical Physics - In the case of a severe accident at a nuclear power plant with light-water reactors, the most effective method for localization of the formed melt (corium) is its retention in... 相似文献
6.
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
7.
Evropeitsev E. A. Serov Yu. M. Nechaev D. V. Jmerik V. N. Shubina T. V. Toropov A. A. 《JETP Letters》2021,113(8):504-509
JETP Letters - The decay kinetics of low-temperature exciton photoluminescence in a heterostructure with multiple GaN/AlN monolayer quantum wells, which is prepared by molecular beam epitaxy, is... 相似文献
8.
Wei Yuting Wang Qihua Liu Wei 《Annals of the Institute of Statistical Mathematics》2021,73(3):535-553
Annals of the Institute of Statistical Mathematics - In this paper, a model averaging approach is developed for the linear regression models with response missing at random. It is shown that the... 相似文献
9.
Journal of Optimization Theory and Applications - We distinguish two kinds of piecewise linear functions and provide an interesting representation for a piecewise linear function between two normed... 相似文献
10.
Numerical Algorithms - In this paper, we combine the ideas of multilevel augmentation methods for solving integral equations and the shifted-inverse power method to develop a new multilevel... 相似文献