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The palladium-catalysed coupling of both 5-iodouridine and 5-iodo-2′-deoxyuridine derivatives with functionalized and non-functionalized arylboronic acids and aryltrimethylstannanes gave moderate to good yields of the corresponding 5-aryluridines and 5-aryl-2′-deoxyuridines. 相似文献
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Hana?DrnovskáEmail author Lubomír?Lap?íkJr. Vilma?Bur?íková Josef?Zemek Ana?M.?Barros-Timmons 《Colloid and polymer science》2003,281(11):1025-1033
The effect of oxygen and ammonia plasma treatments on changes of the surface properties of linear high-density polyethylene (HDPE) was studied. Surface energies of the polymer substrates were evaluated by contact angle measurements using Lifshitz-van der Waals acid-base approach. The surface energy of untreated HDPE is mainly contributed by Lifshitz-van der Waals interactions. After 5 min of plasma treatment, hydrogen bonds are formed on the surface, which is reflected in predominant acid-base interactions. The SEM results obtained demonstrate considerable changes of the surface roughness due to different types of the plasma gas used. Evolution of oxygen- or amino-containing moieties was detected by XPS and ATR FT IR. The prepared polyethylene surfaces were used as a basic support for further fabrication of novel hybrid biocomposite sandwich structures. 相似文献
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Vilma Petkova Ekaterina Serafimova Tiit Kaljuvee Yoncho Pelovsky 《Journal of Thermal Analysis and Calorimetry》2013,113(2):683-692
The shortage of raw materials and the environmental problems due to pollution require development of new green technologies utilizing some wastes and transforming them to secondary raw materials. The aim of this work is to study the properties of poultry waste to propose possibilities to minimizing the released emissions and avoiding the risk for human health and the environment. At the same time, two types of low grade peats with different origin are studied as components for the production of soil conditioners. During the studies, we applied the inductively coupled plasma (ICP) and chemical analysis, powder X-ray diffraction, thermal analysis, IR spectroscopy, and scanning electron microscopy for determining the composition, crystal phase, the shape and size of particles, and thermal stability of the investigated samples. The chemical and the phase compositions of the studied samples confirmed that the content of nutrient compounds and of the carbon substances is suitable as an effective secondary raw material for soil conditioners. It is found that the poultry wastes and peat samples have a similar phase and chemical composition and contain an organic mass in the form of carbon components with amorphous, fibrous, and skeleton-like structure, suitable to be combined with other nutrient-containing compounds. During the thermal treatment, the carbon compounds are oxidized releasing heat. Based on that the materials under study are considered as environmentally friendly fuels, releasing relatively low emissions. 相似文献