Acetontrile (ACN) process is one of the three most widely used distillation processes to produce 1,3-butadiene (BD),which is an important base material and just second to propylene and ethylene in the petrochemical **...
Acetontrile (ACN) process is one of the three most widely used distillation processes to produce 1,3-butadiene (BD),which is an important base material and just second to propylene and ethylene in the petrochemical *** to our experimental and theoretic work, ionic liquid [emim][PF6] as an additive could remarkably improve the performance of the process.
The crevice corrosion of the Ni/Graphite abradable sealing coating with open porous for engine of aircrafts will happen,when it serves in marine environment.A simulated occluded corrosion cell was used to study chemic...
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The crevice corrosion of the Ni/Graphite abradable sealing coating with open porous for engine of aircrafts will happen,when it serves in marine environment.A simulated occluded corrosion cell was used to study chemical changes of Ni/Graphite coating in ***% NaCl solution at 35℃.The corrosion behaviors of Ni in simulated solution was investigated by potentialdynamic polarization test.X-ray diffraction (XRD) was used to study the corrosion *** results showed that as the anodic current passes through the cell,the pH value of occluded solution decreased and the Cl- migrates into the occluded cell,meanwhile the Ni2+ and Na+ migrates out the occluded *** Cl- concentration in the occluded cell increased and Ni(OH)2· XH2O generated outside the occluded *** curves showed that the corrosion potential Ecorr of Ni decreased when the pH decreased and the Cl- enriched.
To solve the weapon network system optimization problem against small raid objects with low attitude,the concept of direction probability and a new evaluation index system are *** calculating the whole damaging probab...
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To solve the weapon network system optimization problem against small raid objects with low attitude,the concept of direction probability and a new evaluation index system are *** calculating the whole damaging probability that changes with the defending angle,the efficiency of the whole weapon network system can be subtly *** such method,we can avoid the inconformity of the description obtained from the traditional index *** new indexes are also proposed,*** index,overlap index and cover index,which help manage the relationship among several *** normalizing the computation results with the Sigmoid function,the matching problem between the optimization algorithm and indexes is well ***,the algorithm of improved marriage in honey bees optimization that proposed in our previous work is applied to optimize the embattlement *** is carried out to show the efficiency of the proposed indexes and the optimization algorithm.
Thermodynamic models of calculating mass action concentrations of structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions has been developed based on the ion ...
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Thermodynamic models of calculating mass action concentrations of structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions has been developed based on the ion and molecule coexistence theory at 298.15K.A transformation coefficient is needed to compare calculated mass action concentration and reported activity because they are obtained at different standard state and concentration *** results show that transformation coefficients between calculated mass action concentrations and reported activities of the same structural units or ion couples change in a very narrow *** transformed mass action concentrations of structural units or ion couples in RbCl-H2O binary system are in good agreement with that of reported activities.
Eulerian granular multiphase model with a drag coefficient correction based on the energy-minimization multi-scale （EMMS） model was used to simulate a semi-industry scale circulating fluidized bed （CFB）. Three-dim...
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Eulerian granular multiphase model with a drag coefficient correction based on the energy-minimization multi-scale （EMMS） model was used to simulate a semi-industry scale circulating fluidized bed （CFB）. Three-dimensional （3D）, time-dependent simulation of a full-loop CFB revealed that the axial profiles of cross-sectionally averaged solid volume fraction, and the radial profiles of solid axial velocity and solid volume fraction were in reasonable agreement with experimental data. Based on this agreement, database derived from experiments not yet accomplished was replenished with such simulations, and fluid regime diagrams and pressure balance around the CFB loop were derived accordingly. This work presents an integrated viewpoint on CFB and unfolds a fresh paradigm for CFB modeling, which can be expected to help resolve certain issues long in dispute but bard for experiments.
A new method of investigating catalytic combustion characteristics of pulverized coal was introduced using synthetical thermal analyzer, that is, the referenced DTA. Ignition temperatures of anthracite with K2CO3, Fe2...
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A new method of investigating catalytic combustion characteristics of pulverized coal was introduced using synthetical thermal analyzer, that is, the referenced DTA. Ignition temperatures of anthracite with K2CO3, Fe2O3, CaCO3 and CeO2 addition were 319°C, 410°C, 400°C and 405°C respectively determined by the referenced DTA. The ignition temperatures decreased by catalysts were observed directly from the reference DTA curves. In addition, variations of heat release during pulverized coal combustion were calculated by the referenced DTA curves. The heat releases of anthracite combustion increased by 340.2 J/g, 352.8 J/g, 348.6 J/g and 264.6 J/g, respectively, with K2CO3, Fe2O3, CaCO3 and CeO2 addition. The above results are accordance with those from conventional DTA experiment. However, the referenced DTA is more effective and direct to show catalytic combustion characteristics of pulverized coal.
The effect of Ca-Fe-Ce series catalyst on the characteristics of anthracite combustion was investigated by thermo-gravimetric analysis. The results showed that there may be a synergetic effect among the components in ...
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The effect of Ca-Fe-Ce series catalyst on the characteristics of anthracite combustion was investigated by thermo-gravimetric analysis. The results showed that there may be a synergetic effect among the components in the composite catalyst and the composite catalyst exhibits better performance than the single one for the anthracite combustion. The combustion characteristics of anthracite are affected by the dispersion of catalyst, heating rate and combustion atmosphere. The catalytic effect is enhanced by increasing the catalyst dispersion. The reduction degree of ignition temperature increases with the increase of heating rate. The ignition temperature decreases significantly with the increase of O2 concentration.
BaF2·CaF2 eutectic and Cr3C2 composite powders coated with NiCr alloy were prepared with the technology of hydrogen reduction hydrothermal process combined with a solid state alloying. NiCr/Cr3C2 -BaF2·CaF2 ...
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BaF2·CaF2 eutectic and Cr3C2 composite powders coated with NiCr alloy were prepared with the technology of hydrogen reduction hydrothermal process combined with a solid state alloying. NiCr/Cr3C2 -BaF2·CaF2 coating was produced by atmospheric plasma spray (APS) using the prepared powders. The microstructure and phase compositions of the powders as well as the deposited coating were analyzed by SEM and XRD, while the friction and wear behavior of the coatings from room temperature to 500C were evaluated using a SRV high temperature tribometer. The NiCr/Cr3C2 -BaF2·CaF2 composite coating exhibited excellent wear-resistant performance by high temperature self-lubrication with high microhardness and cohesive strength. Oxidation, decarburization and ablation of Cr3C2-BaF2·CaF2 during spray were avoided due to the protection by NiCr layer. The friction coefficient of the coating, 0.740.02 at room temperature, gradually decreased with the increase of temperature, a small value of 0.380.03 was achieved as temperature up to 500C, which led to a significant decrease of wear rates of both of the coating and the Si3N4 ball. BaF2·CaF2 eutectic underwent a transition with decrease of shear strength at high temperature from brittle to plastic state, which resulted in the formation on a continuous lubricating layer in the wear track at 500C.
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