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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.
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
3.
Journal of Algebraic Combinatorics - APR tilts for path algebra kQ can be realized as the mutation of the quiver Q in $${\mathbb Z}Q$$ with respect to the translation. In this paper, we show that... 相似文献
4.
Zheng Xinyan Hu Po Yao Ruxian cheng Jinhe Chang Yiheng Wu Haitao Mei Hongying Sun Shuxiang Chen Qingtai liu Fang Chen Shujing Wen Hua 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2217-2226
Journal of Radioanalytical and Nuclear Chemistry - Enhancement of U(VI) biomineralization by Saccharomyces cerevisiae through addition of inorganic phosphorus was studied in this work. The addition... 相似文献
5.
Chinese Journal of Polymer Science - The emerging chemical recyclable polymers, such as poly(γ-butyrolactone) (PGBL) and poly((R)-3,4-trans six-membered ring-fused GBL) (P((R)-M)), provide a... 相似文献
6.
Hu Duo-Duo Gao Qian Dai Jing-Cheng Cui Ru Li Yuan-Bo Li Yuan-Ming Zhou Xiao-Guo Bian Kang-Jie Wu Bing-Bing Zhang Kai-Fan Wang Xi-Sheng Li Yan 《中国科学:化学(英文版)》2022,65(4):753-761
Science China Chemistry - A light-induced, nickel-catalyzed three-component arylsulfonation of 1,3-enynes in the absence of photocatalyst is reported. This methodology exhibited mild conditions,... 相似文献
7.
Given a graph sequence denote by T3(Gn) the number of monochromatic triangles in a uniformly random coloring of the vertices of Gn with colors. In this paper we prove a central limit theorem (CLT) for T3(Gn) with explicit error rates, using a quantitative version of the martingale CLT. We then relate this error term to the well-known fourth-moment phenomenon, which, interestingly, holds only when the number of colors satisfies . We also show that the convergence of the fourth moment is necessary to obtain a Gaussian limit for any , which, together with the above result, implies that the fourth-moment condition characterizes the limiting normal distribution of T3(Gn), whenever . Finally, to illustrate the promise of our approach, we include an alternative proof of the CLT for the number of monochromatic edges, which provides quantitative rates for the results obtained in [7]. 相似文献
8.
Czechoslovak Mathematical Journal - The irregularity of a graph G = (V, E) is defined as the sum of imbalances ∣du ? dv∣ over all edges uv ∈ E, where du denotes the degree... 相似文献
9.
SHANG Anqi ZHAO Lele LI Zhenhua CHENG Zhuang JIN Haixu FENG Zijun CHEN Zhijun ZHANG Haiquan LU Ping 《高等学校化学研究》2022,38(6):1461-1466
Near-infrared(NIR) fluorescent materials with high photoluminescent quantum yields(PLQYs) have wide application prospects. Therefore, we design and synthesize a D-A type NIR organic molecule, TPATHCNE, in which triphenylamine and thiophene are utilized as the donors and fumaronitrile is applied as the acceptor. We systematically investigate its molecular structure and photophysical property. TPATHCNE shows high Tgof 110℃ and Td of 385℃ and displays an aggregation-induced emission(AIE) property. A narrow optical bandgap of 1.65 eV is obtained. The non-doped film of TPATHCNE exhibits a high PLQY of 40.3% with an emission peak at 732 nm, which is among the best values of NIR emitters. When TPATHCNE is applied in organic light-emitting diode(OLED), the electroluminescent peak is located at 716 nm with a maximum external quantum efficiency of 0.83%. With the potential in cell imaging, the polystyrene maleic anhydride(PMSA) modified TPATHCNE nanoparticles(NPs) emit strong fluorescence when labeling HeLa cancer cells, suggesting that TPATHCNE can be used as a fluorescent carrier for specific staining or drug delivery for cellular imaging. TPATHCNE NPs fabricated by bovine serum protein(BSA) are cultivated with mononuclear yeast cells, and the intense intracellular red fluorescence indicates that it can be adopted as a specific stain for imaging. 相似文献
10.
Xinghuo Xiao Wenyan Wang Jiali Wang Prof. Can Yang Prof. Guigang Zhang Prof. Xianjun Lang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(52):e202201244
Conjugated polymers feature promising structure and properties for photocatalytic water splitting. Herein, a hydrolysis strategy was demonstrated to rationally modulate the surface hydrophilicity and band structures of conjugated poly-benzothiadiazoles. High hydrophilicity not only enhances the dispersions of polymeric solids in an aqueous solution but also reduces the absorption energy of water molecules. Besides, both theoretical and experimental results reveal that a more positive valence band potential is generated, which contributes to enhancing the photocatalytic water oxidation performance. Accordingly, the surface-modified conjugated polymers show largely promoted photocatalytic water oxidation activities by deposition of cobalt oxides as cocatalysts. 相似文献