Cellulose - A new strategy was proposed to determine the Kappa number of bleached Eucalyptus globulus kraft pulps based on FT-Raman spectroscopy. Before modeling, smoothing (Savitzky-Golay),... 相似文献
As a promising technique to potentially address the energy crisis and environmental issues, photocatalysis has been reported widely to exhibit various outstanding behaviors in production of new fuels/chemicals and treatment of contaminants. The photocatalytic performance is extremely dependent on the used photocatalysts, so that the design and preparation of efficient photocatalysts are critically important for significantly improving the photocatalytic activity. Among various strategies, the hybridization of metal with semiconductors has recently been attracting more and more research interest owing to their expended spectral absorption, promoted transferring rate of charge carriers and Plasmon-enhanced effect. In this minireview, the metal-facilitated hybrid photocatalysts are overviewed comprehensively to first reveal unique functions of metals in improvement of photoactivity and summarize the emerging metal-involved hybrid systems. Subsequently, the synthetic methods towards hybrid photocatalysts are introduced and their practical applications are emphasized in environmental remediation including degradation of organic pollutants, conversion of harmful gases, treatment of heavy metal ions and sterilization of bacteria. At the end, the challenges for industrializing these hybrid photocatalysts are discussed carefully and future development is suggested rationally. 相似文献
In this paper, we present the theory of constructing optimal generalized helical-wave coupling dynamical systems. Applying the helical-wave decomposition method to Navier-Stokes equations, we derive a pair of coupling dynamical systems based on optimal generalized helical-wave bases. Then with the method of multi-scale global optimization based on coarse graining analysis, a set of global optimal generalized helical-wave bases is obtained. Optimal generalized helical-wave bases retain the good properties of classical helical-wave bases. Moreover, they are optimal for the dynamical systems of Navier-Stokes equations, and suitable for complex physical and geometric boundary conditions. Then we find that the optimal generalized helical-wave vortexes fitted by a finite number of optimal generalized helical-wave bases can be used as the fundamental elements of turbulence, and have important significance for studying physical properties of complex flows and turbulent vortex structures in a deeper level. 相似文献
In this paper, the theory of constructing optimal dynamical systems based on weighted residual presented by Wu & Sha is applied to three-dimensional Navier-Stokes equations, and the optimal dynamical system modeling equations are derived. Then the multiscale global optimization method based on coarse graining analysis is presented, by which a set of approximate global optimal bases is directly obtained from Navier-Stokes equations and the construction of optimal dynamical systems is realized. The optimal bases show good properties, such as showing the physical properties of complex flows and the turbulent vortex structures, being intrinsic to real physical problem and dynamical systems, and having scaling symmetry in mathematics, etc.. In conclusion, using fewer terms of optimal bases will approach the exact solutions of Navier-Stokes equations, and the dynamical systems based on them show the most optimal behavior. 相似文献
We make a mapping from Sierpinski fractals to a new class
of networks, the incompatibility networks, which are scale-free,
small-world, disassortative, and maximal planar graphs. Some
relevant characteristics of the networks such as degree
distribution, clustering coefficient, average path length, and
degree correlations are computed analytically and found to be
peculiarly rich. The method of network representation can be applied
to some real-life systems making it possible to study the complexity
of real networked systems within the framework of complex network
theory. 相似文献
Transition Metal Chemistry - In this study, the shape-controlled synthesis of ruthenium (Ru) nanostructures was examined using microwave irradiation. Dendritic Ru nanostructures, with an average... 相似文献
How to efficiently utilize most abundant biomass of cellulose, lignin and their derivatives has become an emerging challenge as the anticipative oil depletion. In this paper, the ternary anionic copolymer of carboxymethyl cellulose-acrylamide-lignosulfonate (CAL) was successfully prepared by hydrothermal polymerization. Based on the flocculation characteristics of cationic methylene blue, the optimal polymerization process was confirmed as the raw material ratio of 1:1:1, initiator dosage of 0.9 wt %, the reaction time was 5 h and the reaction temperature was 55 °C. The results showed that the decolorization ratio was 87.5% at the CAL dosage of 600 mg/L for the 500 mg/L methylene blue simulated wastewater. The CAL achieved fast flocculation kinetics and super color removal ratios in the wide ranges of environmental pH, temperature and salt concentration. The flocculation mechanism is single charge neutralization. Moreover, the estimated treatment cost of CAL is 68.3% lower than that of commercial anionic PAM. The prepared anionic CAL flocculant has the characteristics of environmental safety, excellent flocculation performance and cost-effectiveness, which shows great potential in the field of dye wastewater treatment, and also provides a feasible way for the effective utilization of biomass resources.
A novel 1D chain-like coordination polymer, {[Pb(CDCA)2(DMF)] · DMF · 2H2O]}n (I) (HCDCA = chenodeoxycholic acid, DMF = dimethyl formamide), has been synthesized by hydrothermal method and characterized by single crystal X-ray diffraction, IR spectroscopy, and elemental analysis (CIF file CCDC no. 996098). X-ray diffraction analyses indicated that I displays distorted octahedral metal centers with secondary building units [Pb(CDCA)2(DMF)] bridged by a pair of μ2-COO?-bridges. In the crystal, interchain O-H?O hydrogen bonds are present and assemble the neighboring 1D chain into a (4,4) sql type three-dimensional (3D) supramolecular topological network. 相似文献
The crystallization of γ‐cyclodextrin‐based metal‐organic framework (CD‐MOF) with inclusion of ferulic acid (FA) was carried out through vapor diffusion of methanol to the aqueous solution of γ‐cyclodextrin (γ‐CD), KOH and FA. Although the crystallization of pure CD was limited in highly basic solution of KOH (pH>13.0), the CD‐MOF with inclusion of FA (FA/CD‐MOF) was able to be formed at pH 6.8 after the neutralization of KOH by FA. The inclusion behavior of FA in CD‐MOF was studied by using differential scanning calorimetry. The data indicate the formation of the stable association between FA and γ‐CD in FA/CD‐MOF. 相似文献