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141.
Piotr Bałczewski Marian Mikołajczyk 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Reactions of α,β and β-phosphonyl radicals with alkenes leading to the formation of the P(C)n-C bonds (n=1 ÷ 3) and illustrated by a synthesis of Methylenomycin B are described. Desulfenylation and deselenylation reactions of α-heterosubstituted α-phosphoryl sulfides and selenides are also presented. 相似文献
142.
Marian Mikoßajczyk Piotr ßyżwa Józef Drabowicz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):357-358
Addition of α-phosphonate carbanions to (S)-sulfinimines 2 gives N-sulfinyl-β-aminophosphonates 3 with a high diastereoselectivity (up to 10:1). The major diastereomer of 3 (R=Ph) was converted into (+)-(R)-β-amino-β-phenylethanephosphonic acid 5. 相似文献
143.
Z. Bielecki T. Stacewicz J. Wojtas J. Mikołajczyk D. Szabra A. Prokopiuk 《Opto-Electronics Review》2018,26(2):122-133
Optoelectronic technology plays an important role in medical diagnosis. In the paper a review of some optoelectronic sensors for invasive and non-invasive human health test is presented. The main attention is paid on their basic operation principle and medical usefulness. The paper presents also own research related to developing of tools for human breath analysis. Breath sample unit and three gaseous biomarkers analyzer employing laser absorption spectroscopy designed for clinical diagnostics were described. The analyzer is equipped with sensors for CO, CH4 and NO detection. The sensors operate using multi-pass spectroscopy with wavelength modulation method (MUPASS-WMS) and cavity enhanced spectroscopy (CEAS). 相似文献
144.
Chmielewska Katarzyna Marciniak Mariola Marciniak Mikołaj 《Aequationes Mathematicae》2023,97(4):805-821
Aequationes mathematicae - In this article we prove that all squares with sides of lengths $$\frac{1}{m+1}, \frac{1}{m+2}, \dots $$ can be packed in a rectangle with a one side fixed and a... 相似文献
145.
The effect of melt temperature on the phase behavior and preferential orientation development in Nylon 6/montmorillonite nanocomposites were investigated at melt spinning temperatures ranging from 230° to 250°C. The fibers were found to exhibit mostly γ crystalline form that is typical of Nylon 6 filled with montmorillonite nanoparticles. At higher take-up speeds α-crystals begin to appear in the crystalline phase. The presence of nanoparticles was found to impart substantial chain orientation levels even at low to moderate take up speeds reaching a plateau at moderate take up speeds. This was attributed to the increased spin line stress in the presence of nanoparticles that increase the overall viscosity due to their large contact areas with the polymer chains. This increased spinline tension was found to cause fiber breakup at moderate speeds. Increasing melt temperature from 230° to 250°C alleviated this problem. 相似文献