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211.
Mahmoud Elgammal Sylvain Prévost Ralf Schweins Reinhold Schneider Michael Gradzielski 《Colloid and polymer science》2014,292(7):1487-1500
We report the synthesis and design of aqueous monodisperse copolymer latexes by miniemulsion polymerization and their application as binders in pigment printing and ink-jet printing of cotton fabrics. For that purpose, miniemulsion radical polymerization was carried out with a high content of the soft butyl acrylate (BA) and a low content of the hard methyl methacrylate (MMA) in the presence of hexadecane as osmotic costabilizer. The addition of small amounts of functional monomers such as methacrylic acid MAA and N-methylol acrylamide NMA to some miniemulsion recipes allowed to impart cross-linking sites and functionality to the copolymer chains. Dynamic light scattering (DLS), small angle neutron scattering (SANS), and transmission electron microscopy (TEM) showed that the particle size diameter and size distributions could be controlled in the range of 50 to 400 nm by the amount of SDS surfactant, while the presence of a costabilizer such as hexadecane determines the particle size and, to a lesser extent, the polydispersity of the obtained miniemulsion latex dispersions. The glass transition temperature of the different miniemulsion latexes ranged between ?14 and ?33 °C, depending on the monomer composition. Selected samples of these nanolatexes were then employed in textile printing. The miniemulsion binders with their uniform shape and smaller size have technological advantages over conventional processes for the pigment and ink-jet printing and yielded better printing properties in terms of softness, fastness, and color strength of the printed fabric. Accordingly, by optimized use of the miniemulsion method, one is not only able to control the particle size but also to improve the properties of these latexes for textile applications. 相似文献
212.
Wright AC Lemdiasov R Connick TJ Bhagat YA Magland JF Song HK Toddes SP Ludwig R Wehrli FW 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,210(1):113-122
A Helmholtz-pair local transmit RF coil with an integrated four-element receive array RF coil and foot immobilization platform was designed and constructed for imaging the distal tibia in a whole-body 7T MRI scanner. Simulations and measurements of the B(1) field distribution of the transmit coil are described, along with SAR considerations for operation at 7T. Results of imaging the trabecular bone of three volunteers at 1.5T, 3T and 7T are presented, using identical 1.5T and 3T versions of the 7T four-element receive array. The spatially registered images reveal improved visibility for individual trabeculae and show average gains in SNR of 2.8× and 4.9× for imaging at 7T compared to 3T and 1.5T, respectively. The results thus display an approximately linear dependence of SNR with field strength and enable the practical utility of 7T scanners for micro-MRI of trabecular bone. 相似文献
213.
We develop a scattering theory of current-induced forces exerted by the conduction electrons of a general mesoscopic conductor on slow "mechanical" degrees of freedom. Our theory describes the current-induced forces both in and out of equilibrium in terms of the scattering matrix of the phase-coherent conductor. Under general nonequilibrium conditions, the resulting mechanical Langevin dynamics is subject to both nonconservative and velocity-dependent Lorentz-like forces, in addition to (possibly negative) friction. We illustrate our results with a two-mode model inspired by hydrogen molecules in a break junction which exhibits limit-cycle dynamics of the mechanical modes. 相似文献
214.
David J. Ashline Andrew J. S. Hanneman Hailong Zhang Vernon N. Reinhold 《Journal of the American Society for Mass Spectrometry》2014,25(3):444-453
Documenting mass spectral data is a fundamental aspect of accepted protocols. In this report, we contrast MSn sequential disassembly spectra obtained from natural and synthetic glycan epitopes. The epitopes considered are clusters found on conjugate termini of lipids and N- and O-glycans of proteins. The latter are most frequently pendant through a CID-labile HexNAc glycosidic linkage. The synthetic samples were supplied by collaborating colleagues and commercial sources and usually possessed a readily released reducing-end linker, a by-product of synthesis. All samples were comparably methylated, extracted, and MSn disassembled to compare their linkage and branching spectral details. Both sample types provide B-ion type fragments early in a disassembly pathway and their compositions are a suggestion of structure. Further steps of disassembly are necessary to confirm the details of linkage and branching. Included in this study were various Lewis and H antigens, 3- and 6-linked sialyl-lactosamine, NeuAc-2,8-NeuAc dimer, and Galα1,3Gal. Sample infusion provided high quality spectral data whereas disassembly to small fragments generates reproducible high signal/noise spectra for spectral matching. All samples were analyzed as sodium adducted positive ions. This study includes comparability statistics and evaluations on several mass spectrometers. Figure
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215.
Mirjam C. K. Geditz Georg Heinkele Asma Ahmed Peter G. Kremsner Reinhold Kerb Matthias Schwab Ute Hofmann 《Analytical and bioanalytical chemistry》2014,406(17):4299-4308
Artesunate (AS), a hemisuccinate derivative of artemisinin, is readily soluble in water and can easily be used in formulations for parenteral treatment of severe malaria. AS is rapidly hydrolyzed to the active metabolite dihydroartemisinin (DHA) and primarily eliminated by biliary excretion after glucuronidation. To investigate systematically the AS metabolism and pharmacokinetics, a novel liquid chromatography–tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of AS and its metabolites DHA and DHA glucuronide (DHAG) in human plasma samples was developed. Compared to previous methods, our method includes for the first time the quantification of the glucuronide metabolite using a newly synthesized stable isotope-labeled analogue as internal standard. Sample preparation was performed with only 50 μL plasma by high-throughput solid-phase extraction in the 96-well plate format. Separation of the analytes was achieved on a Poroshell 120 EC-C18 column (50*2.1 mm, 2.7 μm, Agilent Technologies, Waldbronn, Germany). The method was validated according to FDA guidelines. Calibration curves were linear over the entire range from 1 to 2,500 nM (0.4–961.1 ng/mL), 165 to 16,500 nM (46.9–4,691.8 ng/mL), and 4 to 10,000 nM (1.8–4,604.7 ng/mL) for AS, DHA, and DHAG, respectively. Intra- and interbatch accuracy, determined as a deviation between nominal and measured values, ranged from ?5.7 to 3.5 % and from 2.7 to 5.8 %, respectively. The assay variability ranged from 1.5 to 10.9 % for intra- and interbatch approaches. All analytes showed extraction recoveries above 85 %. The method was successfully applied to plasma samples from patients under AS treatment. Figure
Chemical structures and combined MRM chromatograms of the analytes AS, DHA and DHAG 相似文献
216.
217.
218.
B. Josephson G. Jungner J. G. Reinhold D. W. Wilson L. Cuny Y. Abe S. Kawaguchi A. v. Christiani V. Anger O. Rosenheim R. Ehrström K. Täufel H. Thaler G. Widmann E. Kirk W. R. Bloor H. H. Williams B. N. Erickson I. Avrin S. S. Bernstein I. G. Macy G. Ellis L. A. Maynard R. N. Chopra A. C. Roy R. Feulgen H. Grünberg K. Imhäuser C. A. Grau V. Oliva E. Epstein und H. Lieb 《Fresenius' Journal of Analytical Chemistry》1941,122(3-4):149-160
Ohne Zusammenfassung 相似文献
219.
Reinhold Baer 《Mathematische Zeitschrift》1934,38(1):375-416
Ohne Zusammenfassung 相似文献
220.