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31.
In this study, a new biosynthetic tracer was developed to characterize the virus retention dynamics of membrane systems. This new tracer is a modified bacteriophage obtained by the grafting of enzymatic probes to an MS2 bacteriophage, one of the smallest non-pathogenic bacteria viruses, with an average diameter of about 30 nm. A protocol for the synthesis and purification of this new tracer was developed in this work. The production of this biosynthetic tracer was first qualitatively shown by a chromatographic characterization and an enzymatic test. The average number of probes grafted per phage was then quantified for three batches of tracers made from the same native phage suspension and the same batch of enzymatic probes. This quantification demonstrated the reproducibility of the synthesis protocol developed. 相似文献
32.
Our Fortran codes for hard sphere fluids and their mixtures for the correlation functions that arise from the Percus–Yevick theory and the Verlet–Weis semi-empirical correction have proven useful during a period of nearly four decades and continue to be useful. In order to make these codes even more widely available, a brief summary is presented here and listings of these codes are given in the electronically accessible Supplementary Material to this paper. 相似文献
33.
C. F. Tejero 《Molecular physics》2013,111(23-24):2999-3004
Two analytic approximations for the direct correlation function of a hard-sphere fluid are considered. The first follows from a generalization of the Percus–Yevick result in d dimensions, whereas the second arises in the Rational Function Approximation (RFA) method. Both approximations require the equation of state of the hard-sphere fluid as input. The results, derived after use of the Carnahan–Starling and the Padé 4,3 equations of state in both approaches, are compared with simulation data. The comparison shows that the first approximation is rather accurate in the region inside the core, but inherits the limitation of the Percus–Yevick theory for distances beyond the hard-sphere diameter. On the other hand, the results of the RFA method are also accurate inside the core and capture well the initial part of the tail beyond the hard-sphere diameter, but fail to account for the subsequent oscillations observed in the simulations. Other merits and limitations of the two approaches are reported. 相似文献
34.
Alternative process to hexavalent chromium, substitute materials and new designs are urgently needed owing to the requirement of “clean” manufacture. This comparative study was conducted to systematically investigate the corrosion resistance and lubricated sliding wear behavior of graded Ni-P alloy deposits produced from a single plating bath by electrodeposition and hard Cr deposits, using potentiodynamic polarization and reciprocating ball-on-disc tribometer. Results showed that Ni-P deposits heat-treated at 400 °C with maximum hardness exhibited more than two orders of magnitude higher corrosion resistance than hard Cr deposits in 10 wt.% HCl solution. The Stribeck curves for the heat-treated Ni-P gradient deposits and hard Cr under lubrication conditions were obtained with accurate control of normal load and sliding speed during the wear process, three main different regimes corresponding to different lubrication mechanism were identified. Heat-treated Ni-P gradient deposits showed relatively poor wear resistance than hard Cr deposits under the lubrication conditions, which may be attributed to superior oil-retaining surface structure and the unique “nodular” effect of hard Cr in wear process. 相似文献
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We analyze the iterative structure of unfactorized partonic structure functions in the large-x limit, and derive all-order expressions for the leading-logarithmic off-diagonal splitting functions Pgq and Pqg and the corresponding coefficient functions C?,q and C2,g in Higgs- and gauge-boson exchange deep-inelastic scattering. The splitting functions are given in terms of a new function not encountered in perturbative QCD so far, and vanish maximally in the supersymmetric limit CA−CF→0. The coefficient functions do not vanish in this limit, and are given by simple expressions in terms of the above new function and the well-known leading-logarithmic threshold exponential. Our results also apply to the evolution of parton fragmentation functions and semi-inclusive e+e− annihilation. 相似文献
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The structural and thermodynamic properties of a confined hard ellipse fluid are studied using Monte Carlo simulation. The angular, average number densities and order parameters of hard ellipses confined between hard parallel walls are obtained for various bulk densities, aspect ratios and wall separations. The results show that the effect of the existence of the wall on the molecular fluid structure, either on their directions or their locations, with respect to the bulk, especially close to the walls, is significant. For this system the pressure is also obtained and it is shown that the average density at the wall is proportional to the pressure, βP=〈ρw〉. Our simulation results show that the order parameters depend on the number of the particles in the box unless it exceeds thousand. 相似文献
40.
Masatomo Sumiya Yutaro Kamo Masaki Takeguchi Hideki Yoshikawa Keisuke Kobayashi Minoru Hagino Shunro Fuke 《Applied Surface Science》2010,256(14):4442-4446
Photocathode devices operating in reflection-mode, where the photoemission is detected on the same side as the light irradiation, were developed for the detection of deep ultraviolet light by using p-AlxGa1−xN films grown on Si(1 1 1) substrates. The external quantum efficiencies were as high as 20-15% at 200 nm and 280 nm, while the value was as low as 10−2% at 310 nm. The on-off ratio was more than four orders of magnitude, which represents high solar-blind sensitivity. The escape probability of AlxGa1−xN photocathode was decreased with increase of AlN mole fraction. The effective barrier potential against the photoelectron emission near the surface was reduced due to the upward shift of conduction band of AlxGa1−xN. The photoemission from the AlxGa1−xN films terminated with Cs-O adatoms will be discussed in terms of band diagrams that were evaluated by hard X-ray photoelectron spectroscopy. 相似文献