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11.
Sébastien Simon Stefan Theiler Agnethe Knudsen Gisle Øye Johan Sjöblom 《Journal of Dispersion Science and Technology》2013,34(5):632-640
We have studied the rheological properties of fumed silica particle-stabilized emulsions. Two particles of different polarity were considered, the first more hydrophilic “Aerosil R7200,” the second more hydrophobic “Aerosil R972.” These particles flocculate and probably form a network at the investigated concentration. The flow curves of emulsions stabilized by a single type of particles exhibit yield stress, shear-thinning behavior and thixotropy. Moreover they display rheological features typical of gels. These features are attributed to strengthening of the particle network by droplets. Moreover the rheological properties of w/o emulsions stabilized by hydrophobic are similar to the ones of o/w emulsions stabilized by hydrophilic particles. The rheological properties of o/w emulsions stabilized by mixtures of hydrophilic and hydrophobic particles have then been studied by keeping the total particle concentration constant and varying the mass ratio between particles. The results show that when the hydrophobic particle concentration increases, the viscosity and stability of emulsions decrease establishing evidence that the network is weakened due to preferential orientation of hydrophobic particles towards the oil phase. 相似文献
12.
Ingrid Hauser Ana B. Colaço Julie A. Skjæran Aslak Einbu Kjetill Østgaard Hallvard F. Svendsen Francisco J. Cervantes 《Applied biochemistry and biotechnology》2013,169(4):1449-1458
Large-scale amine-based CO2 capture will generate waste containing large amounts of ammonia, in addition to contaminants such as the actual amine as well as degradation products thereof. Monoethanolamine (MEA) has been a dominant amine applied so far in this context. This study reveals how biological N removal can be achieved even in systems heavily contaminated by MEA in post- as well as pre-denitrification treatment systems, elucidating the rate-limiting factors of nitrification as well as aerobic and denitrifying biodegradation of MEA. The hydrolysis of MEA to ammonia readily occurred both in post- and pre-denitrification treatment systems with a hydraulic retention time of 7 h. MEA removal was ≥99?±?1 % and total nitrogen removal 77?±?10 % in both treatment systems. This study clearly demonstrates the advantage of pre-denitrification over post-denitrification for achieving biological nitrogen removal from MEA-contaminated effluents. Besides the removal of MEA, the removal efficiency of total nitrogen as well as organic matter was high without additional carbon source supplied. 相似文献
13.
LetX=G/H be an affine symmetric space of Hermitian type. For modules in the analytic continuation of the scalar holomorphic discrete
series forG, we show existence and uniqueness (that is, a multiplicity one result) of imbeddings into functions onX. The corresponding intertwining operators are analyzed using our previous methods for discrete series. In a slightly less
explicit way, we also give the analogous results for the continuation of the general discrete series. 相似文献
14.
Søren Fournais Maria Hoffmann-Ostenhof Thomas Hoffmann-Ostenhof Thomas Østergaard Sørensen 《Communications in Mathematical Physics》2002,228(3):401-415
We prove that the electron densities of electronic eigenfunctions of atoms and molecules are smooth away from the nuclei. 相似文献
15.
E. Østgaard 《Physics letters. [Part B]》1973,47(4):303-305
The ground-state energy and pressure of a neutron solid is calculated by means of a modified Brueckner theory. The possibility of a phase transition from normal neutron matter into a neutron solid is then considered, but no phase transition is found to occur for the specific two-body potential assumed. 相似文献
16.
Niels Olaf Østerberg Torben Smith Sørensen Jørgen Birger Jensen 《Journal of Electroanalytical Chemistry》1981,119(1):93-108
The emf of electrochemical cells containing various sorts of salt bridges between various concentrations has been measured. The net diffusion potential over a salt bridge has been treated theoretically. An expression to calculate the net diffusion potential has been derived and tested on values estimated from the emf measurements. A merit factor has been calculated for a saturated KCl bridge separating two HCl solutions and compared with the merit factor estimated from emf measurements on the cell:Pt|Ag|AgCl, HCl(c1)|KCl(sat)|HCl(c2), AgCl|Ag|Pt The practical performance of two commonly used reference electrodes with salt bridges has been tested on emf measurements on KBr solutions. 相似文献
17.
We generalize Israel's formalism to cover singular shells embedded in a non-vacuum Universe. That is, we deduce the relativistic equation of motion for a thin shell embedded in a Schwarzschild/Friedmann-Lemaître-Robertson-Walker spacetime. Also, we review the embedding of a Schwarzschild mass into a cosmological model using curvature coordinates and give solutions with (Sch/FLRW) and without the embedded mass (FLRW). 相似文献
18.
Bronowska A Chilmonczyk Z Leś A Edvardsen O Ostensen R Sylte I 《Journal of computer-aided molecular design》2001,15(11):1005-1023
In the present study experimentally determined ligand selectivity of three methylated buspirone analogues (denoted as MM2, MM5 and P55) towards 5-HT1A and 5-HT2A serotonin receptors was theoretically investigated on a molecular level. The relationships between the ligand structure and 5-HT1A and 5-HT2A receptor affinities were studied and the results were found to be in agreement with the available site-directed mutagenesis and binding affinity data. Molecular dynamics (MD) simulations of ligand-receptor complexes were performed for each investigated analogue, docked twice into the central cavity of 5-HT1A/5-HT2A, each time in a different orientation. Present results were compared with our previous theoretical results, obtained for buspirone and its non-methylated analogues. It was found that due to the presence of the methyl group in the piperazine ring the ligand position alters and the structure of the ligand-receptor complex is modified. Further, the positions of derivatives with pyrimidinyl aromatic moiety and quinolinyl moiety are significantly different at the 5-HT2A receptor. Thus, methylation of such derivatives alters the 3D structures of ligand-receptor complexes in different ways. The ligand-induced changes of the receptor structures were also analysed. The obtained results suggest, that helical domains of both receptors have different dynamical behaviour. Moreover, both location and topography of putative binding sites for buspirone analogues are different at 5-HT1A and 5-HT2A receptors. 相似文献
19.
Branson’s Q-curvature is now recognized as a fundamental quantity in conformal geometry. We outline its construction and present its basic properties. 相似文献
20.
Stefanie Breukers Christer L. Øpstad Hans‐Richard Sliwka Vassilia Partali 《Helvetica chimica acta》2009,92(9):1741-1747
The oft‐claimed ‘good’ water solubility of the food color norbixin ( 3 ) could not be confirmed. In contrast, the potassium salt 5 of norbixin formed suitable dispersions. The surface and aggregation properties of salt 5 were investigated and compared with other naturally occurring and synthetic hydrophilic carotenoids (Table). 相似文献