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排序方式: 共有10000条查询结果,搜索用时 27 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.
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
4.
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
5.
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
6.
张磊 《数学的实践与认识》2021,(1):302-307
设G=(V,E)是一个连通图.称一个边集合S■E是一个k限制边割,如果G-S的每个连通分支至少有k个顶点.称G的所有k限制边割中所含边数最少的边割的基数为G的k限制边连通度,记为λ_k(G).定义ξ_k(G)=min{[X,■]:|X|=k,G[X]连通,■=V(G)\X}.称图G是极大k限制边连通的,如果λ_k(G)=ξ_k(G).本文给出了围长为g>6的极大3限制边连通二部图的充分条件. 相似文献
7.
Liu Jun-Wei Shen Shu-Qian Li Ming Li Lei 《International Journal of Theoretical Physics》2021,60(5):1712-1719
International Journal of Theoretical Physics - Quantum coherence, coming from quantum superposition, occupies a significant position in the field of physics. We put forward a lower bound of the... 相似文献
8.
Technical Physics - Taking damping into account in the problems of structural dynamics is an important and nontrivial problem. Its complexity is primarily determined by the required specification... 相似文献
9.
Abramov B. M. Baznat M. Borodin Yu. A. Bulychjov S. A. Dukhovskoy I. A. Krutenkova A. P. Kulikov V. V. Martemianov M. A. Matsyuk M. A. Turdakina E. N. 《Physics of Atomic Nuclei》2021,84(4):467-474
Physics of Atomic Nuclei - In the FRAGM experiment at the heavy-ion accelerator $$-$$ accumulator complex ITEP $$-$$ TWA, yields of cumulative charged $$\pi$$ mesons have been measured in a... 相似文献
10.
Novikov V. S. Kuznetsov S. M. Kuzmin V. V. Prokhorov K. A. Sagitova E. A. Darvin M. E. Lademann J. Ustynyuk L. Yu. Nikolaeva G. Yu. 《Doklady Physics》2021,66(9):257-263
Doklady Physics - The dependence of Raman spectra of the molecules containing polyene chains on the conjugation length, structure of side and end groups, and isomer type is analyzed theoretically. 相似文献