A high performance liquid chromatography(HPLC) method was proposed to monitor the synthesis and purification of the 1-alkyl-3-methylimidazolium ionic liquid precursors from alkylation of 1-methylimidazole with alkyl h...
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A high performance liquid chromatography(HPLC) method was proposed to monitor the synthesis and purification of the 1-alkyl-3-methylimidazolium ionic liquid precursors from alkylation of 1-methylimidazole with alkyl halides and determine the purity of final *** results showed that separation of 1-methylimidazole from the precursors could be obtained under the HPLC performance conditions such as cation exchange column,acetonitrile/KH2PO4 aqueous solution and 209 nm *** content of unreacted 1-methylimidazole in the precursors could be easily calculated from their corresponding HPLC peak areas with the calibration curve of *** retention times of the 1-alkyl-3-methylimidazolium ionic liquid precursors decreased with their increasing alkyls,and the ionic liquids with the same cation and different anions had almost the same retention times.
Magnetic particles have numerous applications in biotechnology and biomedicine. In this paper we reviewed the synthesis, surface modification and some applications of magnetic particles with focus on their synthesis a...
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Magnetic particles have numerous applications in biotechnology and biomedicine. In this paper we reviewed the synthesis, surface modification and some applications of magnetic particles with focus on their synthesis and surface modification. Various methods have been developed for the production of magnetic particles （magnetic nanoparticles and magnetic composite particles）. For future application magnetic particles must be modified to obtain stability and surface functional groups. Finally, the application of magnetic particles in magnetic separation, drug delivery, hyperthermia, and magnetic resonance imaging are discussed.
Ti/Sb-SnO2 anodes were prepared by thermal decomposition to examine the influence of the amount of Sb dopant on the structure and electrocatalytic capability of the electrodes in the oxidation of 4-chlorophenol. The p...
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Ti/Sb-SnO2 anodes were prepared by thermal decomposition to examine the influence of the amount of Sb dopant on the structure and electrocatalytic capability of the electrodes in the oxidation of 4-chlorophenol. The physicochemical properties of the Sb-SnO2 coating were markedly influenced by different amounts of Sb dopant. The electrodes, which contained 5% Sb dopant in the coating, presented a much more homogenous surface and much smaller mud-cracks, compared with Ti/Sb-SnO2 electrodes containing 10% or 15% Sb dopant, which exibited larger mud cracks and pores on the surface. However, the main microstructure remained unchanged with the addition of the Sb dopant. No new crystal phase was observed by X-ray diffraction （XRD）. The electrochemical oxidation of 4-chlorophenol on the Ti/SnO2 electrode with 5% Sb dopant was inclined to electrochemical combustion; while for those containing more Sb dopant, intermediate species were accumulated. The electrodes with 5% Sb dopant showed the highest efficiency in the bulk electrolysis of 4-chlorophenol at a current density of 20 mA/cm^2 for 180 min; and the removal rates of 4-chlorophenol and COD were 51.0% and 48.9%, respectively.
A kind of output-feedback networked control system was addressed to overcome the defect of feedback lag introduced by the network usage in the networked control system. By introducing a plant model and a buffer into t...
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A kind of output-feedback networked control system was addressed to overcome the defect of feedback lag introduced by the network usage in the networked control system. By introducing a plant model and a buffer into this system, when feedback was available, this system could compute the control output and update the plant model with the plant output, otherwise, compute the control output based on the plant model output instead of plant output. On the condition that the plant was SISO and the error between plant and model existed, the necessary and sufficient condition for closed-loop stability of this system was derived. Simulation indicates that the range of model error within which this system is stable is easy to be derived by using this necessary and sufficient condition.
The velocity profiles and temperature distributions of gas flow in microchannels, for Knudsen numbers ranging from 0.01 to 0.20, are investigated with pseudo-particle modeling (PPM). It has been found that the velocit...
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The velocity profiles and temperature distributions of gas flow in microchannels, for Knudsen numbers ranging from 0.01 to 0.20, are investigated with pseudo-particle modeling (PPM). It has been found that the velocity profiles are mainly affected by Knudsen number and the external force fields applied. When Knudsen number was increased, the slip velocities on the walls increased at the beginning, and then decreased. The temperature distributions were also significantly affected by the external force. The Darcy friction factor increased with increasing Knudsen number, and its variation with Mach number under increased Knudsen number was similar to the so-called premature laminar-turbulent transition observed in experiments.
The effect of different extraction and purification conditions on the microbial protein obtained from solid-state fermentation(SSF)and the effect of periodical dynamic changes of air on protein have been *** mechanism...
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The effect of different extraction and purification conditions on the microbial protein obtained from solid-state fermentation(SSF)and the effect of periodical dynamic changes of air on protein have been *** mechanism of solid-state fermentation with periodical dynamic changes of air is also *** with static solid-state fermentation,periodical dynamic changes of air afford a higher protein mass;from 1 g of the fermentation microbe,5.3 mg of the intracellular protein(an increase of 34.63%)and 9.09 mg of the extracellular protein(an increase of 17.8%)were obtained on the sixth day of *** filter paper activity and carboxymethyl cellulose activity(FPA and CMCase)of the extracellular protein are 1.739μmol/s and 109.592μmol/s,respectively,which represent increases of 60.1%and 21.2%over the corresponding values for static solid-state *** FPA and CMCase of the intra-cellular protein are 0.245μmol/s and 6.392μmol/s,respec-tively,which represent decreases of 22.2%and 38.7%over the corresponding values for static solid-state *** enzyme activity of the microbial extracellular protein in solid-state fermentation with periodical dynamic changes of air on the fifth day is nearly equal to that on the sixth day without periodical dynamic changes of air,so the period of fermentation can be *** sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)experiments suggest that pulsating air pressure stimulation leads to a decrease in the amount of protein component with molecule mass of about 80400Da,and an increase in the amount of protein component with molecule mass of about 28520Da.
Coal pyrolysis can be significantly affected by CoCl2 catalyst. In this paper, the effect of CoCl2 catalyst on the pyrolysis of Huolinhe lignite was investigated in a spout-entrainment reactor and in a thermogravimetr...
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ISBN:
(纸本)9781604238617
Coal pyrolysis can be significantly affected by CoCl2 catalyst. In this paper, the effect of CoCl2 catalyst on the pyrolysis of Huolinhe lignite was investigated in a spout-entrainment reactor and in a thermogravimetric cell. The results showed that the yield of total volatile from lignite fast pyrolysis using CoCl2 catalyst was twice as much as that without CoCl2 catalyst. Moreover, the main components of light tar, including phenol, carboxylic and aliphatic groups were also increased by 150 %, 83 %, 100 % and 200 %, respectively. On the contrary, the slow pyrolysis of lignite was inhibited by CoCl2 catalyst: the yield of total volatile and the yields of phenol and carboxylic groups were all decreased. The different effect of CoCl2 catalyst on fast and slow pyrolysis of coal might be attributed to secondary cracking of tar precursors. In order to recycle Co catalyst, CoCl2 was impregnated to clay zeolite. The catalytic effect of Co-clay zeolite is lower than that of CoCl2 directly impregnated to lignite. However, catalytic pyrolysis of lignite with Co-clay zeolite should be feasible in an industrial setting because it's easy to be separated and recycled.
Based on the observation that the ratio of the perimeter. P, to the square root of the area. A0.5, of the grains for a given material is nearly constant, it is suggested that the grain shape may be treated as a regula...
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Based on the observation that the ratio of the perimeter. P, to the square root of the area. A0.5, of the grains for a given material is nearly constant, it is suggested that the grain shape may be treated as a regular polygon with a non-integral side number. Examining the variation of P/A 0.5-ratio with sintering holding time may provide useful information for sintering dynamics. Further analysis suggests that the P/A0.5 -ratio may be a potential parameter for studying the grain-boundary effect in polycrystalline materials.
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