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71.
72.
Halewyck H Oita I Thys B Dejaegher B Vander Heyden Y Rombaut B 《Electrophoresis》2010,31(19):3281-3287
Poliovirions, purified from infected cell extracts with anion-exchange chromatography, can be analyzed and identified by CE in untreated fused silica capillaries using UV detection. Other subviral particles can be eluted as well from the same infected cell extract using a higher salt concentration buffer on the ion-exchange chromatography. Virions can be identified because of their conversion into empty capsids upon heating at 56°C. As a result of heating, the viral genome is released from the capsid. Here, we show that during this incubation some intermediate particles were found. The latter were identified by enzymatic peak shift analysis. The high salt concentration eluate subviral particles were analyzed with preincubation affinity CE together with their sensitivity for RNase and proteinase K treatment. Electropherograms of the higher salt concentration eluate display a mixture of at least four different subviral particles. One particle proved to have an [N1, H] antigenicity and was resistant to RNase and proteinase K digestion. The remaining particles were all sensitive to proteinase K treatment. This CE method proved to be valuable in the detection, identification and analysis of poliovirions and poliovirus particles offering an alternative powerful, cheap, fast and easy analysis method. 相似文献
73.
Frederik Detobel Ken Broeckhoven Joke Wellens Bert Wouters Remco Swart Mario Ursem Gert Desmet Sebastiaan Eeltink 《Journal of chromatography. A》2010,1217(18):3085-3090
An experimental study was performed to investigate the effects of column parameters and gradient conditions on the separation of intact proteins using styrene-based monolithic columns. The effect of flow rate on peak width was investigated at constant gradient steepness by normalizing the gradient time for the column hold-up time. When operating the column at a temperature of 60 °C a small C-term effect was observed in a flow rate range of 1–4 μL/min. However, the C-term effect on peak width is not as strong as the decrease in peak width due to increasing flow rate. The peak capacity increased according to the square root of the column length. Decreasing the macropore size of the polymer monolith while maintaining the column length constant, resulted in an increase in peak capacity. A trade-off between peak capacity and total analysis time was made for 50, 100, and 250 mm long monolithic columns and a microparticulate column packed with 5 μm porous silica particles while operating at a flow rate of 2 μL/min. The peak capacity per unit time of the 50 mm long monolithic column with small pore size was superior when the total analysis time is below 120 min, yielding a maximum peak capacity of 380. For more demanding separations the 250 mm long monolith provided the highest peak capacity in the shortest possible time frame. 相似文献
74.
Bert Schroer 《Foundations of Physics》2011,41(10):1543-1568
The standard formulation of quantum gauge theories results from the Lagrangian (functional integral) quantization of classical
gauge theories. A more intrinsic quantum theoretical access in the spirit of Wigner’s representation theory shows that there
is a fundamental clash between the pointlike localization of zero mass (vector, tensor) potentials and the Hilbert space (positivity,
unitarity) structure of QT. The quantization approach has no other way than to stay with pointlike localization and sacrifice
the Hilbert space whereas the approach built on the intrinsic quantum concept of modular localization keeps the Hilbert space
and trades the conflict creating pointlike generation with the tightest consistent localization: semiinfinite spacelike string
localization. Whereas these potentials in the presence of interactions stay quite close to associated pointlike field strengths,
the interacting matter fields to which they are coupled bear the brunt of the nonlocal aspect in that they are string-generated
in a way which cannot be undone by any differentiation. 相似文献
75.
Coensel BD Vanwetswinkel S Botteldooren D 《The Journal of the Acoustical Society of America》2011,129(4):EL148-EL153
Recent studies show that introducing sound from water features in urban open spaces may reduce the loudness of road traffic noise, but it is not clear in which situations this measure also improves overall soundscape quality. This work describes a listening experiment on loudness, pleasantness, and eventfulness of stimuli that combine road traffic noise with fountain or bird sound at different sound levels. Adding fountain sound reduced the loudness of road traffic noise only if the latter had low temporal variability. Conversely, adding bird sound significantly enhanced soundscape pleasantness and eventfulness, more than what was achieved by adding fountain sound. 相似文献
76.
Bert Schroer 《Foundations of Physics》2011,41(2):204-241
It is shown that certain kinds of behavior, which hitherto were expected to be characteristic for classical gravity and quantum
field theory in curved spacetime, as the infinite dimensional Bondi-Metzner-Sachs symmetry, holography on event horizons and
an area proportionality of entropy, have in fact an unnoticed presence in Minkowski QFT. 相似文献
77.
Bohumír Bastl Bert Jüttler Miroslav Lávička Tino Schulz Zbyněk Šír 《Mathematics in Computer Science》2014,8(2):299-319
Ringed surfaces and canal surfaces are surfaces that contain a one-parameter family of circles. Ringed surfaces can be described by a radius function, a directrix curve and vector field along the directrix curve, which specifies the normals of the planes that contain the circles. In particular, the class of ringed surfaces includes canal surfaces, which can be obtained as the envelopes of a one-parameter family of spheres. Consequently, canal surfaces can be described by a spine curve and a radius function. We present parameterization algorithms for rational ringed surfaces and rational canal surfaces. It is shown that these algorithms may generate any rational parameterization of a ringed (or canal) surface with the property that one family of parameter lines consists of circles. These algorithms are used to obtain rational parameterizations for Darboux cyclides and to construct blends between pairs of canal surfaces and pairs of ringed surfaces. 相似文献
78.
Back Cover: Molybdenum Speciation and its Impact on Catalytic Activity during Methane Dehydroaromatization in Zeolite ZSM‐5 as Revealed by Operando X‐Ray Methods (Angew. Chem. Int. Ed. 17/2016) 下载免费PDF全文
79.
Mendels P Bert F de Vries MA Olariu A Harrison A Duc F Trombe JC Lord JS Amato A Baines C 《Physical review letters》2007,98(7):077204
We report muon spin rotation measurements on the S=1/2 (Cu2+) paratacamite ZnxCu4-x(OH)6Cl2 family. Despite a Weiss temperature of approximately -300 K, the x=1 compound is found to have no transition to a magnetic frozen state down to 50 mK as theoretically expected for the kagomé Heisenberg antiferromagnet. We find that the limit between a dynamical and a partly frozen ground state occurs around x=0.5. For x=1, we discuss the relevance to a singlet picture. 相似文献
80.
Groothaert MH Smeets PJ Sels BF Jacobs PA Schoonheydt RA 《Journal of the American Chemical Society》2005,127(5):1394-1395
This work reports on the capability of the O2-activated Cu-ZSM-5 and Cu-MOR zeolites to selectively convert methane into methanol at a temperature of 398 K. A strong correlation between (i) the activity and (ii) the intensity of the 22 700 cm-1 UV-vis band, assigned to the bis(mu-oxo)dicopper core, is found (i) as a function of the reaction temperature, (ii) as a function of the Cu loading of the zeolite, and (iii) in comparison to other Cu materials. These three lines of evidence firmly support the key role of the bis(mu-oxo)dicopper core in this selective, low-temperature hydroxylation of methane. 相似文献