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161.
Tobias Fieback Frieder DreisbachMarcus Petermann Roland SpanEckard Weidner 《Fluid Phase Equilibria》2011,301(2):217-224
A novel measuring method is presented here that allows sorption and solvation measurements near to different process conditions. Especially for the sorption kinetics it is important that the measuring conditions are similar to later applications. Particularly for high pressure sorption measurements this claim could not be fulfilled for most technical applications.The advantage of the measuring methods presented here is that solid bed samples in high pressure gravimetry can be measured under flow-through conditions in both directions and, for the first time in high pressure gravimetry, liquid samples can be measured under flow-through conditions. Especially for ionic liquids, of which a large variety of new substances with unknown sorption potentials have been synthesised in the last few years, this results in much shorter measuring times.The first measurements presented here show that the new system allows for measuring times around 26 times shorter for an ionic liquid. 相似文献
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High water‐content thermoresponsive hydrogels via electrostatic macrocrosslinking of cellulose nanofibrils
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Tobias Ingverud Emma Larsson Guillaume Hemmer Ramiro Rojas Michael Malkoch Anna Carlmark 《Journal of polymer science. Part A, Polymer chemistry》2016,54(21):3415-3424
Atom transfer radical polymerization (ATRP) has been utilized to synthesize tri‐ and star‐block copolymers of poly(di(ethylene glycol)methyl ether methacrylate) (PDEGMA) and quaternized poly(2‐(dimethylamino)ethyl methacrylate) (qPDMAEMA). The block copolymers, all with a minimum of two cationically charged blocks, were sequentially used for electrostatic macrocrosslinking of a dilute dispersion of anionic TEMPO‐oxidized cellulose nanofibrils (CNF, 0.3 wt%), forming free‐standing hydrogels. The cationic block copolymers adsorbed irreversibly to the CNF, enabling the formation of ionically crosslinked hydrogels, with a storage modulus of up to 2.9 kPa. The ability of the block copolymers to adsorb to CNF was confirmed by quartz crystal microbalance with dissipation monitoring (QCM‐D) and infrared spectroscopy (FT‐IR), and the thermoresponsive properties of the hydrogels were investigated by rheological stress and frequency sweep, and gravimetric measurements. This method was shown to be promising for the facile production of thermoresponsive hydrogels based on CNF. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3415–3424 相似文献
166.
Close contacts between chalcogen atoms in cyclic dienes and diynes are used to create columnar structures in the solid state. Rigid and fairly planar cycles with chalcogen centers are the preconditions for forming those columnar structures. 相似文献
167.
We present a quantum protocol for the task of weak coin flipping. We find that, for one choice of parameters in the protocol, the maximum probability of a dishonest party winning the coin flip if the other party is honest is 1/sqrt[2]. We also show that if parties restrict themselves to strategies wherein they cannot be caught cheating, their maximum probability of winning can be even smaller. As such, the protocol offers additional security in the form of cheat sensitivity. 相似文献
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A method for determining the orbit types of the action of the group of gauge transformations on the space of connections for gauge theories with gauge group SU(n) in spacetime dimension d4 is presented. The method is based on the one-to-one correspondence between orbit types and holonomy-induced reductions of the underlying principal SU(n)-bundle. It is shown that the orbit types are labelled by certain cohomology elements of spacetime satisfying two relations. Thus, for every principal SU(n)-bundle the corresponding stratification of the gauge orbit space can be explicitly determined. As an application, a criterion characterizing kinematical nodes for physical states in Yang–Mills theory with the Chern–Simons term proposed by Asorey et al. is discussed. 相似文献
170.
C. Andreoiu M. Axiotis G. de Angelis J. Ekman C. Fahlander E. Farnea A. Gadea T. Kröll S.M. Lenzi N. Mărginean T. Martinez M.N. Mineva C. Rossi Alvarez D. Rudolph C.A. Ur 《The European Physical Journal A - Hadrons and Nuclei》2002,15(4):459-462
Excited states in 59Zn were observed for the first time following the fusion-evaporation reaction 24Mg + 40Ca at a beam energy of 60 MeV. The GASP array in conjunction with the ISIS Silicon ball and the NeutronRing allowed for the
detection of γ-rays in coincidence with evaporated light particles. The mirror symmetry of 59Zn and 59Cu is discussed.
Received: 28 May 2002 / Accepted: 10 July 2002 / Published online: 3 December 2002
RID="a"
ID="a"Present address: Oliver Lodge Laboratory, University of Liverpool, P.O. Box 147, Liverpool, L69 7ZE, United Kingdom; e-mail: ca@ns.ph.liv.ac.uk.
RID="b"
ID="b"Present address: Physik-Departament, Technische Universit?t München, D-85748 Garching, Germany.
Communicated by W. Henning 相似文献