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Paweł Mochalski Beata Wzorek Ireneusz Śliwka Anton Amann 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(20-21):1856-1866
Suitability of different types of pre-concentration (solid phase microextraction and sorbent trapping) and detection (flame photometric detector (FPD) and mass selective detector (MSD)) for gas chromatographic determination of sulphur-containing compounds (H2S, MeSH, EtSH, DMS, COS and CS2) in breath-gas was assessed in this study. Several factors like influence of humidity, influence of oxygen, or stability of target compounds in extraction vessels (SPME vials and sorbent tubes) were investigated. Despite poor stability of VSCs in SPME vials and matrix effects (unfavorable influence of humidity), SPME was found to be a fast and reliable enrichment method, which coupled with mass selective detector provided satisfactory LODs of target compounds at the ppt level (from 0.15 ppb for CS2 to 2.3 ppb for H2S). Application of sorbent trapping with two-bed sorbent tubes containing Tenax TA and Carboxen 1000 gave excellent LODs (0.03–0.3 ppb for 200 ml sample and MSD). Stability of investigated VSCs in sorbents was found to be very poor (30–40% losses after 2 h). FPD showed satisfactory sensitivity only when it was coupled with sorbent trapping. Breath samples were collected into Tedlar bags in a CO2-controlled manner. Humidity was removed during sampling (permeation dryer – Nafion) to avoid unfavorable water dependent effects during analysis. 相似文献
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Journal of Plant Growth Regulation - In the presented work attempts have been made to explore effectiveness of the sugar beet (Beta vulgaris L.) seeds priming process in relation to seed quality... 相似文献
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Alexander E. Sorochinsky Toshimasa Katagiri Taizo Ono Alicja Wzorek José Luis Aceña Vadim A. Soloshonok 《Chirality》2013,25(8):i-ii
This work demonstrates that self‐disproportionation of enantiomers via achiral chromatography can be recommended as inexpensive and general method for optical purifica‐ tion of enantiomerically enriched compounds. In particular, the advantage of this approach over conventional recrystallization is that it can be used for both crystalline as well as liquid com‐ pounds. Chirality, 25:365–368, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Kwiatkowska Magdalena Marcinkowska Magdalena Wzorek Alicja Pajkert Romana Han Jianlin Klika Karel D. Soloshonok Vadim A. Röschenthaler Gerd-Volker 《Amino acids》2019,51(9):1377-1385
Amino Acids - This work presents the first study of the self-disproportionation of enantiomers via chromatography (SDEvC) of β-aminophosphonic acid esters, several of which have been... 相似文献
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Alexander E. Sorochinsky Toshimasa Katagiri Taizo Ono Alicja Wzorek José Luis Aceña Vadim A. Soloshonok 《Chirality》2013,25(6):365-368
This work demonstrates that self‐disproportionation of enantiomers via achiral chromatography can be recommended as inexpensive and general method for optical purification of enantiomerically enriched compounds. In particular, the advantage of this approach over conventional recrystallization is that it can be used for both crystalline as well as liquid compounds. Chirality, 25:365‐368, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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