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161.
Summary Flow injection analysis associated with a gradient mixing technique can be used for the determination of free acidity and total acidity (sum of free and bonded hydrogen ions) in a few microliters by reaction with suitable acid/base indicators and UV/VIS-detection. A rapid analysis of the two parameters in single raindrops in dependence on their size is possible [1]. 相似文献
162.
P. K. Volkov 《Journal of Applied Mechanics and Technical Physics》1991,32(3):379-383
Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 3, pp. 87–91, May–June, 1991. 相似文献
163.
N. M. Agababyan M. R. Atayan M. Charlet J. Czyżewski E. A. De Wolf K. Dziunikowska A. M. F. Endler Z. Sh. Garutchava H. R. Gulkanyan R. Sh. Hakobyan J. K. Karamyan D. Kisielewska W. Kittel S. S. Mehrabyan Z. V. Metreveli E. C. Oliveira K. Olkiewicz F. K. Rizatdinova E. K. Shabalina L. N. Smirnova M. D. Tabidze L. A. Tikhonova A. V. Tkabladze A. G. Tomaradze F. Verbeure S. A. Zotkin 《Zeitschrift fur Physik C Particles and Fields》1996,71(1):405-414
The NA22 data onπ ? π ? correlations are analyzed in terms of a number of two- and three-dimensional parametrizations (Gaussian space-time, Goldhaber, Bowler string-like, Bertsch hydrodynamical, Kopylov-Podgoretskii, etc.). Contrary to the results obtained for e+e? andµp collisions, the Goldhaber parametrization, as well as string-like models, fail in describing the hadron-hadron data. Better fits are obtained in the framework of surface-emitting fireball-like models, both when including and excluding hydrodynamical expansion of nuclear matter. Our results indicate that pion radiation occurs at earlier stages of matter evolution than in nuclear collisions. 相似文献
164.
K. K. Kalnin'sh D. N. Glebovskii M. E. Bedrina E. K. Roshchina 《Journal of Structural Chemistry》1992,33(5):636-643
Institute of High-Molecular-Weight Compounds, Russian Academy of Sciences. Leningrad State University Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 5, pp. 20–27, September–October, 1992. 相似文献
165.
The leading logarithmic corrections to the critical behavior of a dilute uniaxial (Ising) ferromagnet in the disordered phase are derived using renormalization group methods. The values of the exponents in the logarithmic terms differ from those given by previous authors. 相似文献
166.
167.
Electrochemical oxidation of thio/carbohydrazide and their hydrazone derivatives Benzaldehyde thiocarbohydrazone [BTCH] diacetylene
thiocarbohydrazone [DATCH] have been studied in Brit-ton Robinson buffer in aqueous and nonaqueous media at a glassy carbon
electrode. The effects of pH, sweep rate, concentration, temperature and surfactants have been studied. The complex bis (carbo/thiocabohydrazide) Zn(II) chloride was also subjected to voltammetric analysis in order to understand the reactivity
both in free and metal bound states. The reaction conditions were optimized for the determination of above compounds in micrograms
quantities by differential pulse voltammetry, analytical utility of this investigation is also highlighted. 相似文献
168.
169.
170.
Susanne K. Wiedmer Toni Andersson Marika Sündermann Marja‐Liisa Riekkola Heikki Tenhu 《Journal of Polymer Science.Polymer Physics》2007,45(19):2655-2663
Cationic polyelectrolytes were synthesized and used as semipermanent coating materials for capillaries in electrophoresis. The polyelectrolytes used were a homopolymer of poly(methacryl oxyethyl trimethylammonium chloride) (PMOTAC) and its poly(ethylene glycol) (PEG)‐grafted analogue. Two PMOTAC polyelectrolytes, with molar masses of 85,000 and 300,000 g/mol, and PEG‐grafted PMOTAC with a molar mass of 280,000 g/mol were synthesized and then characterized by size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR) spectroscopy. Attachment of the polyelectrolytes to the wall of the fused silica capillary for electrophoresis caused the electroosmotic flow (EOF) to reverse. The polyelectrolyte coatings were tested over the pH range 2–11 at different buffer ionic strengths, and the most stable and strongest anodic EOFs were obtained at acidic pH values with low ionic strength buffers. Between runs the capillary is merely rinsed for 2 or 3 min with the background electrolyte solution. With the PMOTAC coatings at pH values ≤5, the RSDs of the EOFs were less than 2.9% after 60 injections. The effects of the molar mass of the polycation and of PEGylation of PMOTAC on the interactions between the polycations and basic proteins were studied at acidic pH values. The differences in the effective electrophoretic mobilities, resolution values, and plate numbers of the proteins with the different coatings were due to the EOF, as demonstrated through calculations of reduced mobilities, relative resolution values, and relative plate numbers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2655–2663, 2007 相似文献