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71.
Abstract The similarities and differences in the polymerization of MMA (methyl methacrylate) and iBMA (isobutyl methacrylate) in a ternarycomponent system have been investigated from a turbid emulsion to a transparent microemulsion by increasing the surfactant concentration. In spite of the difference in the solubilities of these two monomers in the aqueous phase, the rate dependencies on the surfactant concentration of both monomers were found to be about 0.30 for the emulsion polymerization and about 0.60 for the microemulsion polymerization with monomer concentrations higher than 5 wt%. However, at a low monomer concentration (3 wt%), different negative rate dependencies of ?0.93 and ?1.20 were obtained for microemulsion polymerization of MMA and iBMA, respectively. The results are discussed in terms of particle nucleation mechanisms. 相似文献
72.
We investigate the fundamental connection between quadrature squeezing and continuous variable entanglement within a general
class of two-coupled oscillator systems. We determine the quantitative relationship between them through the squeezing parameter
and the entanglement entropy of the lowest energy eigenstate of the coupled oscillator systems numerically. Unlike the relation
between entanglement and uncertainty product, we found that this relationship is, by no means, the same for the whole class
of coupled oscillator systems: to a large extent it depends on the order and strength of the anharmonic potential, which implies
that knowledge of the anharmonic potential of the coupled oscillator system is required before one can characterize the degree
of entanglement through the squeezing parameter. Our results reveal that a more effective approach to enhance squeezing is
to adjust the anharmonicity of the system potential, instead of increasing the quantum correlations between the oscillators.
In addition, by probing into a quantum catastrophe model, we uncover transitions in the entanglement entropy and squeezing
relation as the potential changes from a single well to a triple well, and then a double-well structure. The transitions appear
through distinct entropy–squeezing relation, with a multi-well structure displaying a larger change in the antisqueezing behavior
of the position quadrature than the single-well structure, for the same change in the entanglement entropy. 相似文献
73.
When an intense laser pulse irradiates a solid-density foil target, electrons produced at the relativistic critical density can be accelerated to relativistic energy by the ponderomotive force. When a plasma fiber is attached to the back of the foil, the produced relativistic electrons are guided to propagate along the fiber for a long distance, because the high-current electron beam induces strong radial electric fields in the fiber. Transport and heating of intense laser-driven relativistic electrons in both wire and hollow plasma fibers are compared theoretically and numerically. We found that the coupling efficiency from the laser to the plasma fiber depends on the fiber structure. Because of the enhanced return currents in the wire fiber, the temperature in the wire fiber is higher than that in the hollow fiber. 相似文献
74.
In this paper, we prepared a novel reactor with switchable ability to address present challenges in tandem catalyst. By introducing mussel-inspired moiety, this goal was achieved via preparing a “smart” polymer reactor which can open or closes the entry tunnel of the targeted substrate in cascade reactions. The catalyst consisted of two functional layers acting as tandem catalytic parts and one smart layer with mussel-inspired moieties as a controlled middle switch. The top and the bottom layer were made of molecularly imprinted polymers and catalytic components, like acidic parts and metal nanoparticles, respectively. The middle layer made of polymeric dopamine (PDPA) and acrylamide with self-healing ability will allow or inhibit the intermediate product for the reaction, thus controlling the process of the tandem catalysis. As a result, the novel catalyst exhibited self-controlled tandem catalysis, which provides new opportunities to design smart tandem catalysts, showing a promising prospect in this area. 相似文献
75.
Pseudolinearity and efficiency 总被引:9,自引:0,他引:9
First order and second order characterizations of pseudolinear functions are derived. For a nonlinear programming problem
involving pseudolinear functions only, it is proved that every efficient solution is properly efficient under some mild conditions. 相似文献
76.
P. Baillon E. Barrelet M. Benayoun J. Chauveau D. Chew M. Ferro-Luzzi J. Kahane D. Lellouch P. Leruste P. Liaud F. Moreau J.M. Perreau J. Séguinot R. Sené J. Tocqueville M. Urban 《Physics letters. [Part B]》1980,94(4):533-540
Hoping to find resonant structures in the momentum dependence of π?p elastic scattering we have measured the differential cross section for this reaction at c.m. angles near 90°. An intense pion beam (≈ 107π/s) has been used, together with a high incident momentum resolution (dP/P ≈ 2 × 10?4), to scan the region of laboratory momenta from 5.75 to 13.02 GeV/c (c.m. energy from 3.42 to 5.03 GeV). The sensitivity attained by the experiment is such that signals would have been seen corresponding to the formation of non-strange baryon resonances having width larger than ≈ 0.1 MeV and elasticity larger than a few per cent. Within these limits no resonances were sighted. 相似文献
77.
Multiperipheral models are used to show how the Regge expansion, while lacking threshold branch points, may nevertheless approximate the localized physical effects of “peripheral” thresholds. Examples are given to demonstrate that a single pair of complex poles is capable of representing even the lowest inelastic thresholds in both total and single-particle inclusive cross sections. The Regge mechanism that allows the position of a threshold to depend sensibly on the masses of incoming and outgoing particles is elucidated. 相似文献
78.
Excitation functions at θ = 90° have been measured for , , and , in the range E3He = 3–19 MeV. The first reaction has also been studied at θ = 40°. Excitation functions at 90° have also been measured for and for E3He = 19–26 MeV. Angular distributions have been measured for the first four reactions.For the most excitation functions, a broad peak is observed, several MeV wide, centred at about Ex≈ 20 MeV. Superimposed on this, in some cases, are narrower peaks, with width ≈ 1 MeV. Energies and widths have been extracted for all resonances.Cluster-model calculations have been carried out, using methods similar to those which have proved successful for low-lying states in A= 18–19 nuclei. No satisfactory correspondence with the present results was found. The shell model has been used to calculate Γ3He and Γγ for 1?ω excitations in the final nuclei. These generally show good agreement with the trends of the experimental data. The results are consistent with the excitation of the giant dipole resonance in 3He capture, but much more weakly than in proton capture. 相似文献
79.
A suite of numerical techniques was utilized in a concerted fashion for the efficacious multivariate chemometrics analysis of hyperspectral infrared imaging data of exfoliated oral mucosa cells. Based on the vector representation of infrared spectrum a1xnu), spectral vector properties (SVP) are demonstrated to possess underpinning spectral information that was exploited in crucial chemometrics analyses; which include outlier spectra identification, selection for a subset of imaged mid-infrared spectra that contain good oral mucosa cell signals, and, for the first time, obtain major biochemical constituent spectra via the band-target entropy minimization (BTEM) curve resolution algorithm. The relative concentration spatial distribution of the major biochemical constituents observed, namely membrane lipids and various cellular protein structures (alpha-helix, beta-sheet, turns and bends), were subsequently acquired through multi-linear regression and were displayed as chemical contour maps. Amongst the set of numerical algorithms employed, two novel unsupervised clustering algorithms were developed and tested. One is useful for outlier spectra detection, and the other aids the selection of pertinent spatially distributed spectra that possess oral mucosa cell mid-infrared spectra with good signal-to-noise ratio. It is anticipated that this developed numerical suite will serve as an effective multivariate chemometrics protocol for cellular studies and biomedical diagnostics via infrared imaging. 相似文献
80.
Norwahyu Jusoh Thiam Leng Chew Kok Keong Lau Azmi Mohd Shariff 《Separation & Purification Reviews》2016,45(4):321-344
In the early stage of membrane technology development in gas separation, utilization of polymeric membranes has gained attention due to their robustness and ease of fabrication. However, the performance of polymeric membranes is limited by the trade-off between permeability and selectivity. Meanwhile, inorganic membrane is capable to exhibit great enhancement in separation performance but unfortunately its fabrication process is hard and costly. Thus, development of mixed matrix membranes (MMMs) by incorporating inorganic fillers into the polymer matrix has become a potential alternative to overcome the limitations of polymeric and inorganic membranes in gas separation. Nevertheless, fabrication of defect-free MMMs with improved separation performance and without compromising the mechanical and thermal stability is extremely difficult and challenging. In the current review paper, various types of inorganic fillers for MMMs fabrication and recent reported efforts to tailor the underlying problems on MMMs fabrication were discussed. The future outlook to advance the performance of MMMs in gas separation especially for CO2/CH4 separation was highlighted. 相似文献