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951.
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A phosphorus-containing tri-ethoxysilane (dopo-icteos) reacting from the nucleophilic addition reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (dopo) and 3-(trieoxysilyl) isocyanate (icteos) was synthesized. The structure of dopo-icteos was confirmed by 1H, 13C, 31P NMR and IR spectra. A triethylamine catalyzed mechanism for the dopo-icteos synthesis was proposed and verified by NMR spectra. The phosphorus-containing epoxy/SiO2 and polyimide/SiO2 nanocomposites were prepared from the in-situ curing of diglycidyl ether of bisphenol A (DGEBA)/4,4-diaminodiphenylmethane(DDM)/dopo-icteos, and imidization of poly(amic acid) of pyromellitic dianhydride (PMDA)/4,4′-oxydianiline (ODA)/dopo-icteos, respectively. The microstructure and morphology were investigated by 29Si NMR, scanning electron microscope (SEM), EDS (Si and P mapping) analysis and atomic force microscope (AFM). The thermal properties, flame retardancy and dielectric properties of the organic-inorganic hybrids were investigated by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), limiting oxygen index (LOI), thermal gravimetric analysis (TGA) and dielectric analyzer (DEA). 相似文献
955.
Mixer-settler counter-current chromatography with a barricaded spiral disk assembly with glass beads
Ito Y Qi L Powell J Sharpnack F Metger H Yost J Cao XL Dong YM Huo LS Zhu XP Li T 《Journal of chromatography. A》2007,1151(1-2):108-114
A novel spiral disk is designed by placing barricades at 6 mm intervals in the middle of the spiral channel to divide the channel into multiple sections. Glass beads are placed in every other section so that the planetary motion produces repetitive mixing and settling of polymer phase systems. Performance of this mixer-settler spiral disk assembly was examined for separation of lysozyme and myoglobin with a polymer phase system. The best results were obtained with a spiral disk equipped with barricades with openings ranging from 1.2 to 0.4 mm on each side at a high revolution speed up to 1200 rpm. 相似文献
956.
Yan Y Xiong W Li X Lu T Huang J Li Z Fu H 《The journal of physical chemistry. B》2007,111(9):2225-2230
The geometrical rule of molecular packing parameters in a bolaamphiphile solution was tested with experimental results. By modifying the solution conditions to change the molecular packing parameters, the morphology of the aggregate was successfully manipulated in a single-chain bolaamphiphile, disodium phenyl-1,4-bis (oxyhexanoate) (i.e., C6PhC6Na2 solution). Micelle-vesicle-tube transformation was observed by changing the pH and the addition of NaBr or octanol. In the mixed systems of oppositely charged bola/surfactants, the molecular packing parameter's role is related to the mixing ratio. 相似文献
957.
Zhi Ting XU 《数学学报(英文版)》2007,23(7):1189-1198
By using vector Riccati transformation and averaging technique, some oscillation criteria for the quasilinear elliptic differential equation of second order,
ΣNi,j=1Di[Ψ(y)Aij(x)|Dy|^p-2Djy]+p(x)f(y)=0,
are obtained. These theorems extend and include earlier results for the semilinear elliptic equation and PDE with p-Laplacian. 相似文献
958.
The l-quasi Nil Radical of Lattice-ordered Rings 总被引:1,自引:0,他引:1
§ 1.l- q Ideals and the l- q Radical of an l- ring Generalizing the notion of quasi nil of rings to lattice-ordered rings(l-rings) ,we de-fine l-quasi nil ideals(l-q ideals) and the l-quasi nil radical(l-q radical) of l-rings.Theproperties of the l-q radical and the structure of l-q semisimple rings are studied.Fur-thermore,we consider the l-q radical of full l-matrix l-rings and l-rings with minimumcondition on single sided l-ideals. Throughout this paper R denotes an l-ring if not spec… 相似文献
959.
960.
Yingtan Yu Ying Lyu Ting Zhang Lin Liu Bing Fan Jian Wang Chaoxing Zhang 《Molecules (Basel, Switzerland)》2021,26(21)
Iopromide (IOP), an iodinated X-ray contrast medium (ICM), is identified as a precursor to iodide disinfection byproducts that have high genotoxicity and cytotoxicity to mammals. ICM remains persistent through typical wastewater treatment processes and even through some hydroxyl radical-based advanced oxidation processes. The development of new technologies to remove ICMs is needed. In this work, mackinawite (FeS)-activated sulfite autoxidation was employed for the degradation of IOP-containing water. The experiment was performed in a 500 mL self-made temperature-controlled reactor with online monitoring pH and dissolved oxygen in the laboratory. The effects of various parameters, such as initial pH values, sulfite dosages, FeS dosages, dissolved oxygen, and inorganic anions on the performance of the treatment process have been investigated. Eighty percent of IOP could be degraded in 15 min with 1 g L−1 FeS, 400 μmol L−1 sulfite at pH 8, and high efficiency on the removal of total organic carbon (TOC) was achieved, which is 71.8% via a reaction for 1 h. The generated hydroxyl and oxysulfur radicals, which contributed to the oxidation process, were identified through radical quenching experiments. The dissolved oxygen was essential for the degradation of IOP. The presence of Cl− could facilitate IOP degradation, while NO3− and CO32− could inhibit the degradation process. The reaction pathway involving H-abstraction and oxidative decarboxylation was proposed, based on product identification. The current system shows good applicability for the degradation of IOP and may help in developing a new approach for the treatment of ICM-containing water. 相似文献