Silicon - The nature of the opening silicate- based surface affects the chemical interaction, spectroscopic and antimicrobial efficiency. The aim of this approach was to evaluate the spectroscopic... 相似文献
Silicon - Magnesium calcium silicate nanostructures (MCSNS) loaded with (0.0, 0.6, 0.9, and 1.2 wt%) of Cephradine-drug consisting of mesoporous particles were functionally prepared by sol-gel... 相似文献
The catalytic filter, V2O5-WO3-TiO2 supported on a ceramic filter, is known as a promising material for treating particulates and NOx simultaneously at optimum temperatures around 320°C. In order to improve its catalytic activity at low temperatures, the
effect of Pt addition on the catalytic filter has been investigated. Catalytic filters, Pt-V2O5-WO3-TiO2/SiC, were prepared by co-impregnation of Pt, V, and W precursors on TiO2 coated-SiC filter by vacuum aided-dip coating. The Pt-added catalytic filter shifted the optimum working temperature from
280–330°C (for the non Pt-impregnated filter) to 180–230°C, providing Nx slip concentration less than 20 ppm for the treatment of 700 ppm NO at a face velocity of 2 cm/s with the same value over
the non Pt-added catalytic filters. The promotional effect following the addition of Pt is believed to result from electrical
modification of the catalyst maintaining a high electron transfer state. Ammonia oxidation was also observed to be dominant
above the optimal temperature for SCR. 相似文献
The effect of shear on floc properties was observed through population balance to comprehend the mechanisms of flocculation, in particular the role of restructuring. Little fundamental attention has been given before to the shear influence responsible for creating compact aggregates, while the floc characteristics might differ in other conditions. It is crucial to understand how aggregates evolve to steady state, if their properties are to be ‘tailored’ to suit subsequent solid-liquid separation. From a previous experimental study (Langmuir 18(6) (2002) 1974), restructuring was observed to occur extensively in the flocculation of latex particles in couette-flow, and was proposed to be responsible for the decrease in floc size on their transition to equilibrium. On the other hand, flocs of larger primary particles were more susceptible to breakage, with densification occurring as a result of fragmentation and re-aggregation. Denser flocs were found when structural deformation dominated, particularly in the initial stage of the process, while comparatively tenuous ones were observed when formation and breakage kinetics were the governing mechanisms. The distinct manners in which aggregates of different primary particle sizes evolved with time, were replicated with a population balance that incorporated the floc structural variation; verifying that restructuring indeed played a crucial role under certain flocculation conditions. 相似文献
The effects of platinum (Pt) and silver (Ag) metallisation in the photocatalytic oxidation of resorcinol at pH 3 ± 0.5 have been investigated. The photocatalytic degradation of resorcinol was significantly improved by Pt/TiO2, while the presence of Ag/TiO2 enhanced the initial photocatalytic degradation rate of resorcinol slightly. Likewise, the photocatalytic mineralisation of resorcinol continued to be enhanced by Pt/TiO2, but it was retarded when Ag/TiO2 was used.
The function of Pt and Ag deposits on the surface of TiO2 has been found to be markedly influenced by the interaction of resorcinol and its degradation products with the metal deposits. The presence of Pt or Ag on the surface of TiO2 altered the distribution of degradation products of resorcinol as well as the production of photoactive species for the photocatalytic oxidation of resorcinol. The X-ray photoelectron spectroscopy (XPS), zeta potential and transmission electron microscopy (TEM) analyses have indicated that the contrasting effect of Pt and Ag deposits were governed by the oxidation states and the catalytic property of metal deposits. In addition to that, it has been found that the roles of metal deposits are specific and should not be generalised. 相似文献
In a competitive business environment, the textile industrialists intend to propose diversified products according to consumers
preference. For this purpose, the integration of sensory attributes in the process parameters choice seems to be a useful
alternative. This paper provides fuzzy and neural models for the prediction of sensory properties from production parameters
of knitted fabrics. The prediction accuracy of these models was evaluated using both the root mean square error (RMSE) and
mean relative percent error (MRPE). The results revealed the models ability to predict tactile sensory attributes based on
the production parameters. The comparison of the prediction performances showed that the neural models are slightly powerful
than the fuzzy models. 相似文献
Given a planar point set sampled from an object boundary, the process of approximating the original shape is called curve reconstruction. In this paper, a novel non‐parametric curve reconstruction algorithm based on Delaunay triangulation has been proposed and it has been theoretically proved that the proposed method reconstructs the original curve under ε‐sampling. Starting from an initial Delaunay seed edge, the algorithm proceeds by finding an appropriate neighbouring point and adding an edge between them. Experimental results show that the proposed algorithm is capable of reconstructing curves with different features like sharp corners, outliers, multiple objects, objects with holes, etc. The proposed method also works for open curves. Based on a study by a few users, the paper also discusses an application of the proposed algorithm for reconstructing hand drawn skip stroke sketches, which will be useful in various sketch based interfaces. 相似文献
Arterial bypass grafts tend to fail after some years due to the development of intimal thickening (restenosis). Non-uniform hemodynamics following a bypass operation contributes to restenosis and bypass failure can occur due to the focal development of anastomotic intimal hyperplasia. Additionally, surgical injury aggravated by compliance mismatch between the graft and artery has been suggested as an initiating factor for progress of wall thickening along the suture line Vascular grafts that are small in diameter tend to occlude rapidly. Computational fluid dynamics (CFD) methods have been effectively used to simulate the physical and geometrical parameters characterizing the hemodynamics of various arteries and bypass configurations. The effects of such changes on the pressure and flow characteristics as well as the wall shear stress during a cardiac cycle can be simulated. Recently, utilization of fluid and structure interactions have been used to determine fluid flow parameters and structure forces including stress and strains relationships under steady and transient conditions. In parallel to this, experimental diagnostics techniques such as Laser Doppler Anemometry, Particle Image Velocimetry, Doppler Guide wire and Magnetic Resonance Imaging have been used to provide essential information and to validate the numerical results. Moreover, clinical imaging techniques such as magnetic resonance or computed tomography have assisted considerably in gaining a detailed patient-specific picture of the blood flow and structure dynamics. This paper gives a review of recent numerical investigations of various configurations of coronary artery bypass grafts (CABG). In addition, the paper ends with a summary of the findings and the future directions. 相似文献
Wet agglomeration mechanisms developing in low shear mixers have been described considering a fractal morphogenesis process that links the median size of the agglomerates with their solid volume fraction via a fractal dimension. It appears fundamental to integrate the polydispersity of the generated structures (nuclei, agglomerates, dough pieces) in the analysis of the agglomeration process in order to approach the industrial problems. The objective of this study is to correlate the influence of the physicochemical characteristics of several liquid binders, on the fractal agglomeration mechanisms. To do so, we considered the values of the fractal model parameters. The obtained results confirmed that semolina wet agglomeration follows a fractal morphogenesis for the different applied liquid binders. Our results also showed a marked influence of the studied physicochemical properties of the liquid binder on the value of the fractal model parameters. During wet agglomeration in low shear mixers, the mechanisms implied during agglomeration (wetting, nucleation and growth) do not occur consecutively, but they coexist throughout at each water contents. 相似文献
A novel magnetic nano-sorbent was synthesized by Schiff’s base formation via covalent bonding of gelatin to the surface of nano-magnetite-immobilized-3-aminopropyltrimethoxysilane (Nano-Fe3O4-Si-N=Gelatin). The structure was confirmed by the FT-IR, TGA, and SEM. The maximum capacity of Cd(II) and Pb(II) were identified as 440 and 400 µmol g?1, respectively. The separation characteristics were evaluated in presence of various controlling factors. The sorption processes of Cd(II) and Pb(II) were found to follow the postulates of Langmuir, Brunauer-Emmer-Teller, and Dubinin Radushkevich isotherm models. The potential applications of Nano-Fe3O4-Si-N=Gelatin in water treatment of Cd(II) and Pb(II) were successfully accomplished using a micro-column technique. 相似文献