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111.
112.
András Varga Mónika Huszár Zsófia Dobos Éva Kiss Anikó Horváth Miklós Idei 《Electrophoresis》2009,30(11):1923-1928
Lipophilicity and methylene selectivity of mixed pseudo‐stationary phases (PSPs) (containing lithium dodecyl sulphate (LDS) and lithium perfluorooctanesulphonate (LiPFOS) in different molar ratios) applied in MEKC have been investigated. Micellar proportion (tprop,mic, a quantity expressing that how much time is spent by the analyte in the micellar phase related to its whole migration time), CLOGP50 value (showing the value of hydrophobicity of a molecule spending exactly 50% of its migration time in the PSP) and methylene selectivity have been determined for different LDS/LiPFOS mixed phases. Values of the above‐mentioned parameters have been determined for analytes with different chemical structures (alkylbenzene and alkylphenone homologous series, alcohols). Good linear correlation was obtained between either the micellar proportion, CLOGP50, or methylene selectivity and the phase composition for the mixed phases. Lipophilicity and methylene selectivity of the mixed LDS/LiPFOS PSPs can be calculated and can continuously be changed by mixing the two single phases (LDS and LiPFOS) in the appropriate (and calculable) portion. 相似文献
113.
Kéki S Szilágyi LS Deák G Zsuga M 《Rapid communications in mass spectrometry : RCM》2003,17(8):783-787
A detailed investigation of the most commonly used plasticizers, such as phthalate, adipate and trimellitate esters, using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and post-source decay (PSD) MALDI-TOFMS/MS is described. It is shown that PSD MALDI-TOFMS/MS is capable of unambiguous determination of the different types of plasticizers. The determination of the types of plasticizers from different PVC samples by PSD MALDI-TOFMS/MS, without the need for solvent extraction, is also demonstrated. The fragmentation mechanisms of these plasticizers cationized with protons and sodium ions are also reported. 相似文献
114.
Recently much attention has been focused on the theory of quasi-random graph and hypergraph properties. The class of quasi-random graphs is defined by certain equivalent graph properties possessed by random graphs. We shall investigate propertiesP which do not imply quasi-randomnes for sequences (G
n
) of graphs on their own, but do imply if they hold not only for the whole graphG
n
but also for every sufficiently large subgraph ofG
n
. Here the properties are strongly connected to countingnot necessarily induced subgraphs of a given type, while in a subsequent paper we shall investigate the properties connected with counting induced subgraphs.Dedicated to the memory of Paul ErdsResearch supported by OTKA N1909. 相似文献
115.
Chang-Jo F. Chung Miklós Csörgő Lajos Horváth 《Annals of the Institute of Statistical Mathematics》1990,42(1):21-36
Some new confidence bands are established for the quantile function from randomly censored data. The method does not require estimation of the density function. As an application, we construct bands for the quantile function of the length of fractures in the granitic plutons near Lac du Bonnet, Manitoba, where an Underground Research Laboratory is being built for the nuclear waste disposal program in Canada.Geological Survey of Canada Contribution Number 10386.Research partially supported by an NSERC Canada Grant.Research done while at Carieton University, supported by NSERC Canada and EMR Canada Grants of M. Csörg. 相似文献
116.
Mária Horváth Cagatay Ipbüker Miklós Hegedűs Tibor Kovács Alan H. Tkaczyk 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(2):391-400
Our previous studies indicated the suitability of tobacco plants for biomonitoring remediated depositories, due to their 210Po and 210Pb accumulation ability. The methods and requirements of testing 210Pb uptake by leaf-surface adsorption was investigated and implemented in the construction of a controlled environment. Uranium ore (theoretical Rn concentration 638 Bqm?3) was the main source of radon and progeny. Rn concentrations were measured by RAD7, AlphaGUARD, EQF 3220, RTM 2100 and CR-39 SSNTDs (411–516 Bqm?3). Activity concentrations of the attached and unattached fractions were determined by EQF 3220. The results are indicative of good measurement setup for tracking 210Po(Pb) uptake pathways. 相似文献
117.
Szilágyi Imre Miklós Kállay-Menyhárd Alfréd 《Journal of Thermal Analysis and Calorimetry》2019,135(6):2915-2915
Journal of Thermal Analysis and Calorimetry - 相似文献
118.
Viktor Kelemen Miklós Bege Dr. Dániel Eszenyi Nóra Debreczeni Dr. Attila Bényei Dr. Tobias Stürzer Prof. Dr. Pál Herczegh Prof. Dr. Anikó Borbás 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(64):14555-14571
A comprehensive optimization and mechanistic study on the photoinduced hydrothiolation of different d - and l - hexo- and pentoglycals with various thiols was performed, at the temperature range of RT to −120 °C. Addition of thiols onto 2-substituted hexoglycals proceeded with complete 1,2-cis-α-stereoselectivity in all cases. Hydrothiolation of 2-substituted pentoglycals resulted in mixtures of 1,2-cis-α- and -β-thioglycosides of varying ratio depending on the configuration of the reactants. Hydrothiolation of unsubstituted glycals at −80 °C proceeded with excellent yields and, except for galactal, provided the axially C2-S-linked isomers with high selectivity. Cooling was always beneficial to the efficacy, increased the yields and in most cases significantly raised the stereoselectivity. The suggested mechanism explains the different conformational preferences of the intermediate carbon-centered radicals, which is a crucial factor in the stereoselectivity of the reactions. 相似文献
119.
120.