With the development of the removal of organic pollutants in the soil and water environment, antibiotics have been considered as emerging pollutants and received considerable attention among the scientific community. Thus, there is a need for an effective, economical, fast, operational feasible and environmental-friendly technology to remove antibiotics. Adsorption technology would be one of the most promising option on the basis that it best meets the criteria we set out above. From the most primitive activated carbon to the most innovative modified biochar, carbon-based materials have played a significant role in the adsorption process of antibiotics all the time. This paper reviews the adsorption behavior of some representative antibiotics (e.g., chloramphenicols, sulfonamides, tetracyclines, flouroquinolones) over various carbonaceous materials (i.e., activated carbon, carbon nanotubes, graphene, and biochar). Nevertheless, in addition to the structural characteristics and adsorption capacities of carbon-based materials, a special emphasis was placed on the underlying adsorption mechanisms and roles of different influencing factors in the adsorption process. Moreover, the knowledge gaps and research challenges have been highlighted, including design and optimization of the carbonaceous materials for antibiotics adsorption.
Identification and quantification of small organic molecules capable of binding to a protein of interest with reasonable affinity and specificity is a central problem. Via developing DNA-encoded recognizing probe, we validate a proof-of-principle for constructing of small target-to-DNA conversion that screens the small molecule-protein interaction. Successful identification of beta-indole acetic acid, abscisic acid, or 2,4-dichlorophenoxyacetic acid/corresponding antibody binding implies its fascinating potential for interrogating small molecule/protein interaction.
Multifractal theory has been widely used in different kinds of fields. In this paper, methods were proposed to extract two kinds of multifractal descriptors of gray series and two-dimensional surfaces for gray image based on the multifractal detrended fluctuation analysis. The proposed multifractal parameters can be well described by texture feature through the test of some textures. Three aspects of experiments have been conducted to verify the robustness of the proposed parameters, which include noise immunity, degree of image blurring and compression ratio. Comparisons were conducted between the proposed parameters and other kinds of texture feature parameters calculated by the standard multifractal analysis, the method of differential box counting and the methods of gray level co-occurrence matrix. Results demonstrate that the proposed exponents of H(2) and h(2) have great noise immunity and are robust to image compression and blurring.
In this paper, multi-fractal characteristics of speech signals are analyzed based on MF-DFA, and it is found that the multi-fractal features are influenced greatly by frame length and noise, besides, there is a little difference between them among speech frames. Secondly, motivated by framing and using frame shift to ensure the continuity and smooth transition of speech in speech signals processing, an advanced MF-DFA (MF-DFA with forward moving overlapping windows) is proposed. The length of moving overlapping windows is determined by parameter θ. Given the value of time scale s, we have MF-DFA with the maximum moving overlapping windows and MF-DFA with half overlapping windows when θ=1/s and θ=1/2 respectively. Moreover, when θ=1 we exactly have MF-DFA. Numerical experiments and analysis illustrate that the multi-fractal characteristics based on AMF-DFA outperform MF-DFA and MF-DMA in stability, noise immunity and discrimination.
Micro-coiled carbon fibers<&wdkj&>Catalysts<&wdkj&>Electrochemical deposition<&wdkj&>Sulfur<&wdkj&>Chemical vapour deposition<&wdkj&>Scanning electron microscopy
Micro-coiled carbon fibers were directly prepared on the graphite substrate using co-electrodeposition of nickel and sulfur as catalysts, in this paper. The diameter of coil and that of micro-coiled carbon fiber are about 800 nm and 400 nm, respectively. Compared with the current preparation methods of catalysts, electrochemical deposition is an effective, cheap and simple technique. Especially, this method is suitable for preparation of ally catalyst. The parameters of electrochemical deposition (deposition time and current density) have little influence on helix of growth and growth mechanism of carbon fibers. By adjusting the electrolyte solution, the amount of sulfur in catalyst are easily carried out, and it is found that sulfur content in catalyst plays an important role on morphological characteristics of carbon fibers.
We performed first-principles calculations to quantify the effect of 26 transition metals on the mechanical properties of vanadium (V) alloys. The generalized stacking-fault (GSF) energies of the solutes were evaluated in three slip systems. Solutes with similar atomic radii to that of V present high GSF energies, which increase the energy barrier for double-kink nucleation and result in excellent strengthening effect. This size effect indicates that noble metals can significantly improve the mechanical strength of V alloys.
Chinese Physics B,2010年19(3):55-60 ISSN：1674-1056
[Kang Guo-Dong; Ouyang Xi-Cheng; Deng Xiao-Juan; Fang Mao-Fa] Hunan Normal Univ, Coll Phys & Informat Sci, Changsha 410081, Hunan, Peoples R China.;[Ouyang Xi-Cheng] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Huang Li-Yuan] Changsha Univ, Dept Elect & Commun Engn, Changsha 410003, Hunan, Peoples R China.
[Fang Mao-Fa] Hunan Normal Univ, Coll Phys & Informat Sci, Changsha 410081, Hunan, Peoples R China.
entanglement sudden death;concurrence;two-photon Jaynes-Cummings model;Kerr-like medium
In this paper, the entanglement dynamics of a double two-photon Jaynes-Cummings model with Kerr-like medium is investigated. It is shown that initial entanglement has an interesting subsequent time evolution, including the so-called entanglement sudden death effect. It is also shown analytically that the Kerr-like medium can repress entanglement sudden death and enhance the degree of atom-atom entanglement. A more interesting fact is that the Kerr effect is more obvious when each of the two cavities with have the Kerr-like medium than only one of them with the Kerr-like medium.
Electron mediators have the ability to facilitate electron acceptance and donation, which can accelerate the electron transfer during the electrochemical process. Few research has been reported about electroactive polymer nanospheres as redox mediators for sensing to date. In this study, we synthesized a new electroactive ferrocene derivative polymer nanospheres (FPS) via a facile and self-assembly method. The obtained FPS was characterized by UV-Vis spectra, Fourier transform infrared spectroscopy, transmission electron microscopy and dynamic light scattering. Based on the electroactive property of FPS, a new electrochemical sensor for acetaminophen (AP) based on the nanocomposite of multi-walled carbon nanotubes-ploy-diallyl-dimethyl-ammonium chloride-FPS (MWCNT-PDDA-FPS) was firstly developed. The greatly enhanced electrochemical performance towards AP determination can be obtained owing to the electrocatalysis of electroactive FPS and good conductivity of MWCNT. The AP sensor exhibits a wide sensing linear range from 3 to 1100 mu M and the detection limit is 0.6 mu M(S/N = 3). Therefore, these ferrocene derivative polymer nanospheres may become a new nanomaterial to construct of platforms for bioanalytical and electrochemical immune research in the future. (C) 2018 Elsevier Ltd. All rights reserved.