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61.
CATAZONE is a new process of heterogeneous catalytic ozonation in which water is ozonated in the presence of a solid catalyst composed of titanium dioxide. The efficiency of this O3/TiO2 system has been compared to the two well-known oxidant systems: ozone alone and ozone combined with hydrogen peroxide.
This comparison was undertaken on three models of natural organic compounds : an aquatic fulvic acid, a protein and a disaccharide. The first results showed the following order of relative efficiency: O3/TiO2 > O3/H2O2 > O3 as far as Total Organic Carbon (TOC) removal was concerned. 相似文献
62.
有机化合物如有机金属化合物、有机酸、有机胺和有机硫化物等在加氢精制催化剂的研制中具有重要作用,在制备催化剂的中用这些有机化合物处理可提高催化剂的活性和稳定性或降低成本,本文对这些有机化合物在这方面应用的技术加以综述。 相似文献
63.
H. Giebl A. Berner G. Reischl H. Puxbaum A. Kasper-Giebl R. Hitzenberger 《Journal of aerosol science》2002,33(12):1623-1634
The cloud droplet activation of monodisperse laboratory aerosols consisting of single organic and inorganic substances as well as a mixture of several substances was investigated using the University of Vienna cloud condensation nuclei counter (CCNC). The CCNC operates on the principle of a static thermal diffusion chamber. Water vapour supersaturations can be set in the range from 0.1% to 2%. Aqueous solutions of oxalic acid and malonic acid as well as solutions of inorganic compounds (NaCl and (NH4)2SO4) were nebulized in a Collison atomizer and then passed through a closed-loop differential mobility particle spectrometer to produce monodispersed particles. An internally mixed aerosol consisting of ammonium sulphate, oxalic acid and malonic acid with relative concentrations resembling those found in cloud water at a mountain station [Löflund, Kasper-Giebl, Schuster, Giebl, Hitzenberger, Reischl et al. (2002) Atmos. Environ. 36, 1553] was also investigated for cloud condensation nuclei (CCN) activation. All these particles were activated at supersaturations expected from Köhler theory. Oxalic and malonic acid particles are therefore expected to be good atmospheric CCN both as pure particles and as internally mixed particles containing other chemical compounds. 相似文献
64.
Dario Natali Mario Caironi Marco Sampietro Andrew P. Meacham Steven J. Vickers Michael D. Ward 《Optical Materials》2006,28(12):1362-1365
We report on the electrochromic behavior of a dinuclear ruthenium complex, which provides high environmental stability together with an intense absorption maximum at 1237 nm in solution in its +3 oxidation state. To verify its optoelectronic properties, we used this complex as the photoactive material in a planar photodetector prototype for near-infrared light pulses, succeeding in the detection of a train of light pulses at a wavelength of 1280 nm. 相似文献
65.
Till Böcking Michael James Christopher L. Brown Kevin D. Barrow 《Thin solid films》2006,515(4):1857-1863
Poly(amidoamine) dendrimers were attached to activated undecanoic acid monolayers, covalently linked to smooth silicon surfaces via Si-C bonds. The resulting ultra-thin dendrimer films were characterized by X-ray photoelectron spectroscopy (XPS), X-ray reflectometry (XR) and atomic force microscopy (AFM). XPS results suggested amide bond formation between the dendrimer and the surface carboxylic acid groups. XR yielded thicknesses of 10 Å for the alkyl region of the undecanoic acid monolayer and 12 Å for the dendrimer layer, considerably smaller than the diameter of these spherical macromolecules in solution. This was consistent with AFM images showing collapsed dendrimers on the surface. It was concluded that the deformation arose from a large number of amine groups on the surface of each dendrimer reacting efficiently with the activated surface, whereby the dendrimers can deform to fill voids while spreading over the activated surface to form a homogeneous macromolecular layer. 相似文献
66.
67.
A mathematical model was developed to estimate the efficacy of coagulation–flocculation treatment for removing neutral hydrophobic organic chemicals from raw drinking water. The model assumed that the only significant removal mechanism was the destabilization and settling of organic matter containing sorbed anthropogenic organic compounds. The model was validated with standard jar tests using compounds with a range of hydrophobicities (log?Kow = 1.89?to?5.48), including contaminant candidate list chemicals, pesticides, pharmaceuticals, and endocrine disrupting chemicals. Final concentrations of test compounds after coagulation and flocculation were in good agreement with model estimations for synthetic waters composed of Aldrich (Milwaukee, WI) humic acid solutions. The final compound concentrations in coagulated natural waters from two drinking water reservoirs were about 80% lower than those estimated with the model. Overestimations of treated water concentrations by the model were attributed to an increase in sorption by natural organic matter when coiled in aluminum hydroxide flocs, compared to sorption to dispersed natural organic matter in untreated water. 相似文献
68.
Yu Qiu 《Materials Research Bulletin》2005,40(5):794-799
Novel blue-emitting cyanuric acid-melamine complexes CAx·M1−x (x = 0.8-0.9) have been prepared by a simple two-step procedure from urea. Relatively strong and pure blue-light emission with a maximum at 470 nm was observed from these complexes. These complexes are very promising light-emitting materials due to their good thermal stability. 相似文献
69.
豆类低聚糖的开发应用 总被引:3,自引:0,他引:3
本文对有关豆类低聚糖的分布,生理功能,分离纯化途径及食品加工性能等方面进行了分析和论述,认为豆类低聚糖是一类有利于人体健康的新型低聚糖,值得开发利用。 相似文献
70.
H. Fujiwara H.‐J. Lee H.‐B. Cui H. Kobayashi E. Fujiwara A. Kobayashi 《Advanced materials (Deerfield Beach, Fla.)》2004,16(19):1765-1769