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301.
L.J.M. Van de Klundert M.R.E. Bos J.A.M. Van der Meij H.A. Steffens 《Physics letters. A》1977,62(7):487-489
The osmotic pressure of 3He-4He mixtures was measured along the phase separation curve at temperatures up to 500 mK by balancing it with the fountain pressure of pure 4He. The usefullness of the secondary osmotic pressure thermometer was reinvestigated. 相似文献
302.
Irradiation of 2,4,6-tri-(tert,-butyl)thiobenzaldehyde with some alkoxy-, alkylthio-, and phenyl-allenes - gave one stereoisomer of a (2+2)-cycloadduct, viz. thietane in high yields (75–95%). Ringclosure is in agreement with MNDO-calculations. 相似文献
303.
Werner Bos 《Mathematische Annalen》1967,175(4):341-344
Ohne Zusammenfassung 相似文献
304.
H. Domininghaus K. J. Rauterkus H. Kelker H. Bergmann U. Bos K. Dehnicke 《Colloid and polymer science》1982,260(1):110-112
305.
A.S. Clough C.I. Beard D.V. Bugg J.A. Edgington J. Hall K. Bos J.C. Kluyver R.A. Kunne L. Linssen R. Birsa F. Bradamante S. Dalla Torre-Colautti M. Giorgi A. Martin A. Penzo P. Schiavon A. Villari S. Degli-Agosti D. Rapin 《Physics letters. [Part B]》1984,146(5):299-302
Measurements are reported of p?p total cross sections from 388 to 599 MeV/c in small momentum steps. Statistical errors are typically ±0.4%and the normalisation uncertainty is ±0.7%. There is no evidence for the “S-meson”. 相似文献
306.
The aggregation of teicoplanin was studied in four solutions: 0.06 M phosphate buffers pH 4.3 and 6.3, both with and without 10% (v/v) of acetonitrile. Conductometry, capillary electrophoresis, cyclic voltammetry, and static light scattering were employed to determine the critical micelle concentration (CMC) of teicoplanin. Dynamic light scattering was used to give an additional information on the size and the size distribution of the particles formed. While the CMC was found in solutions without acetonitrile, attempts to detect any CMC failed in solutions containing acetonitrile. The results point out to different solvating mechanism in solutions with and without acetonitrile, leading to two different schemes of association. 相似文献
307.
Renault M Bos MP Tommassen J Baldus M 《Journal of the American Chemical Society》2011,133(12):4175-4177
Multidomain proteins constitute a large part of prokaryotic and eukaryotic proteomes and play fundamental roles in various physiological processes. However, their structural characterization is challenging because of their large size and intrinsic flexibility. We show here that motional-filtered high-resolution solid-state NMR (ssNMR) experiments allow for the observation and structural analysis of very large multidomain membrane proteins that are characterized by different motional time scales. This approach was used to probe the folding of the 790-residue membrane protein BamA, which is the core component of the Escherichia coli outer membrane protein assembly machinery. A combination of dipolar- and scalar-based two-dimensional ssNMR experiments applied to two uniformly (13)C,(15)N-labeled BamA variants revealed characteristic secondary structure elements and distinct dynamics within the BamA transmembrane protein segment and the periplasmic POTRA domains. This approach hence provides a general strategy for collecting atomic-scale structural information on multidomain (membrane) proteins in a native-like environment. 相似文献
308.
Janečková L Kalíková K Vozka J Armstrong DW Bosáková Z Tesařová E 《Journal of separation science》2011,34(19):2639-2644
Cyclofructans (CFs), a new class of chiral selectors, have been recently introduced for application in liquid chromatography and capillary electrophoresis. So far, derivatized CFs have performed interesting separation possibilities for a variety of compounds. The current work is focused on characterization of three different CF-based chiral stationary phases (CF-based CSPs), i.e. isopropyl carbamate cyclofructan 6 (IP-CF6), R-naphthylethyl carbamate cyclofructan 6 (RN-CF6) and dimethylphenyl carbamate cyclofructan 7 (DMP-CF7). The linear free energy relationship (LFER) model was used to reveal the dominant interactions participating in the complex retention mechanism. A set of 44 different test solutes, with known solvation parameters, was used to determine the regression coefficients of the LFER equation under two mobile-phase compositions in normal separation mode. The LFER results showed that hydrogen bond acidity, hydrophobicity and dipolarity/polarizibility mostly affect the retention and separation process on the CF-based columns in the studied separation systems. 相似文献
309.
Qiu H Loukotková L Sun P Tesařová E Bosáková Z Armstrong DW 《Journal of chromatography. A》2011,1218(2):270-279
New stationary phases for hydrophilic interaction liquid chromatography (HILIC) were synthesized by covalently attaching native cyclofructan 6 (CF6) to silica gel. The chromatographic characteristics of the new stationary phases were evaluated and compared to three different types of commercial HILIC columns. The CF6 columns produced considerably different retention and selectivity patterns for various classes of polar analytes, including nucleic acid compounds, xanthines, β-blockers, salicylic acid and its derivatives, and maltooligosaccharides. Univariate optimization approaches were examined including organic modifier (acetonitrile) contents and buffer pH and salt concentration. The thermodynamic characteristic of the CF6 stationary phase was investigated by considering the column temperature effect on retention and utilizing van't Hoff plots. CF6 based stationary phases appear to have exceptionally broad applicability for HILIC mode separations. 相似文献
310.
Martin Franc Jiří Vojta Jana Sobotníková Pavel Coufal Zuzana Bosáková 《Chemical Papers》2014,68(1):22-28
Fused silica capillary columns of the internal diameter of 320 μm were packed with the Nucleosil C18 stationary phase of 5 μm using the slurry packing method. The time of the bed compaction phase, packing pressure, and the use of ultrasound varied to study their influence on the column performance. Van Deemter curves were measured and separation impedance values were calculated in order to assess both separation efficiency and kinetic performance of the columns. Selected columns were tested again after nine months to evaluate the stability of their beds. Separation efficiencies of all columns were similar, but a major difference, caused by the use of ultrasound, was observed in the bed stability. Columns sonicated for 25 minutes during the bed compaction phase exhibited unchanged performance in the course of several months, while the performance of non-sonicated columns decreased. 相似文献