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991.
This study was carried out to compare EPS (Extracellular Polymeric Substances) composition between conventional activated
sludge (AS) and activated sludge dosed with clinoptilolite (CAS). Additionally, those were compared with organic removal efficiency
in the effluent in conjunction with EPS concentrations. The experiments were conducted at SRT (Solids Retention Time) ranging
from 5 to 100 d. For the CAS, proteins were more readily observed for SRT 20 and 100 d compared to that of the AS. Polysaccharide
concentration in the sludge was greatly increased for the CAS, but it was significantly diminished when the SRT was extended.
The level of EPS concentration observed from the effluent had the same pattern of variation for the two different types of
systems. Regardless of type of reactor, the ratio of proteins for sludge versus effluent was independent of SRT, but the ratio
of polysaccharides diminished as SRT increased. In the long run, the degree of protein synthesis directly ascribed to concurrent
enhancement of SCOD removal efficiency was slightly more in the CAS. It was decided that clinoptilolite added system could
be more reliably retrofitted to a conventional activated sludge process. 相似文献
992.
Summary Anisotropic orientation of liquid crystalline epoxy(LCE) resin on carbon fiber(CF) surface was investigated and it was correlated
with curing behavior and thermomechanical properties of LCE. Anisotropic orientation of a LCE resin was spontaneously induced
on CF surface along a long molecular axis of CF during curing and the anisotropic orientation was maintained after curing.
Curing of LCE was accelerated by alignment of LCE on CF and anisotropic orientation of LCE enhanced dynamic modulus of CF
reinforced LCE composites. 相似文献
993.
Effect of Precursor and Solvent on Morphology of Zirconia Nanoparticles Produced by Combustion Aerosol Synthesis 总被引:1,自引:0,他引:1
Zirconia nanoparticles were synthesized using a flame-based system involving spray droplet combustion of different precursor solutions. The characteristics of the feed were varied by varying the precursor compound, precursor concentration, and solvent type, and by using droplets of different mean sizes. When large droplets were used, agglomerated particles were formed when an organometallic precursor was used and large cenospheric particles were produced when an inorganic precursor was used. Reduction of the droplet size to a number-mean droplet diameter of 3.2 μm resulted in the production of solid spherical particles regardless of the precursor type. When an inertial impactor was used to eliminate droplets larger than 2.3 μm, the large particles in the final product were eliminated and uniformly sized solid zirconia particles having a smaller mean size were produced. The final particle size did not vary with the concentration of the precursor, indicating that multiple ceramic particles resulted from each precursor-containing droplet. 相似文献
994.
Gel permeation chromatography and thin layer chromatography have been used respectively to separate and characterize the first seven members of an epoxy resin polymer homologous series on a preparative and analytical scale. The epoxy resin was formed by the reaction between Bisphenol-A and epichlorhydrin. NMR was used to identify the oligomers. The relationship between extinction coefficient and degree of polymerisation was also determined. 相似文献
995.
Bothexo- andendo-brevicomin reduced the response of flyingDendroctonus ponderosae (Coleoptera: Scolytidae) to an attractant composed oftrans-verbenol and terpenes or oftrans- andcis-verbenol and terpenes in a stand ofPinus contorta var.murrayana. These data suggest that racemicexo- andendo-brevicomin may interrupt aggregation in populations of mountain pine beetle colonizing lodgepole pine; functions of the natural chiral compounds are unknown.Research supported by NSF grants DEB 77-11367 and PCN 79-21708 and the O.S.U. School of Forestry. O.S.U. Agric. Exp. Sta. Tech. Paper No. 5713. 相似文献
996.
Kwang‐Pill Lee Anantha Iyengar Gopalan See‐Hee Lee Ali Md Showkat Young Chang Nho 《应用聚合物科学杂志》2006,102(4):3912-3918
Conducting polydiphenylamine was used to encapsulate silica nanoparticles through the oxidative polymerization of diphenylamine in the presence of ultrasonic irradiation. The polymerization was performed in the presence of sodium lauryl sulfate as a surfactant. Experiments performed in the absence of ultrasound clearly demonstrated that the application of ultrasonication played multiple roles in the preparation of a composite of polydiphenylamine with silica nanoparticles. Ultrasonication dispersed the silica nanoparticles, converted sodium lauryl sulfate to lauryl alcohol, and augmented the dispersion of the silica‐nanoparticle/polydiphenylamine composite in an organic medium. Silica‐nanoparticle/polydiphenylamine composites were also prepared in the absence of ultrasound and/or sodium lauryl sulfate. The silica‐nanoparticle/polydiphenylamine composites were characterized with Fourier trans form infrared spectroscopy, ultraviolet–visible/near‐infrared spectroscopy, and thermogravimetric analysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3912–3918, 2006 相似文献
997.
A new graphical estimation technique is proposed for the determination of the kinetic parameters describing an autocatalytic reaction. A differential scanning calorimeter was used to monitor the reaction kinetics of an epoxy-based vinyl ester resin. The method utilizes information from a zero initial reaction rate, conversation at vitrification, the ratio of reaction rate constants under different isothermal conditions, and characteristics of the phenomenological kinetic model with assumptions being made about the overall reaction order. By fitting data to the integrated reaction rate equation with adjustments for the isothermal conditions, the kinetic parameters are estimated without using a linear or nonlinear regression method. Different kinetic parameters can be estimated from data before and after the gel point which was obtained from the relationship between the glass transition temperature and the degree of cure. 相似文献
998.
Cheng-Chang Lee Chen-Chia Chou Dah-Shyang Tsai 《Journal of the American Ceramic Society》1997,80(11):2885-2890
The 1/3 <111>-type ordering of Ba(Zn1/3 Ta2/3 )O3 (BZT) can be transformed to 1/2 <111>–type ordering by substituting the La3+ cation into the A site. The 1/3 <111> ordering in BZT is shown to be reduced, discontinued, and then replaced by 1/2 <111> ordering, using X–ray diffraction, electron microscopy, and Raman spectroscopy. On the other hand, potassium–substituted BZT only displays a reduction in the degree of ordering. 相似文献
999.
The electrocatalytic activities of Ru-Pt binary oxide electrodes prepared by thermal decomposition for both oxygen and chlorine evolution reactions (OER and CER) were investigated by cyclic voltammetry (CV) and log i/E relationships (Tafel study). Both CV and Tafel studies revealed that the electrodes from the coating solutions with 60 and 20 mol % Pt content possessed the maximum apparent activity for OER and optimal apparent activity for CER/hypochlorite production, respectively. The specific activity (i/q
*) revealed that mixing of the RuO2 and PtO
x
had no synergistic effects for OER due to the occurrence of phase segregation, which was revealed by element mapping/surface morphologies and Auger electron spectroscopy. Lower current efficiencies for hypochlorite production were found on the freshly prepared binary electrodes (type I electrodes) than on those having been treated by repetitive CVs (type II electrodes). Stability testing of both type I and II electrodes was measured in 0.5 m NaCl solution at 300 mA cm–2 for 480 h, indicating that both type I and II electrodes are quite stable under the above conditions. 相似文献
1000.
Various reactions occur between pyrite (FeS2) in coal and CaO to form CaS when a finely pulverized intimate mixture of coal and CaO is coked at 900 °C in an inert atmosphere. The effectiveness of lime and calcined dolomite (CaO.MgO) in promoting this reaction has been evaluated; calcined dolomite is somewhat more effective than lime over coal/ oxide weight ratios from 2.8 to 14. The degree of conversion of pyrite to calcium sulphide at a coal/calcined dolomite weight ratio of 7 has been determined as a function of time at 900 °C; coking time in excess of 2.5 h does not have a significant effect. It has been shown that the total sulphur lost on coking coal/lime mixtures decreases and the percentage of FeS, originating from the dissociation of pyrite, converted to CaS increases as the amount of lime added increases. But although the total sulphur content of coke produced in the presence of CaO is then higher than when the coal is coked without lime, the pyritic sulphur has been converted to CaS which is more amenable to chemical conversion to H2S. A method is outlined for determining CaS in the coked mixture in the presence of FeS. 相似文献