The transformation behaviors of Pb fractions during composting of Pb-polluted waste without inoculants and with the inoculants of Phanerochaete chrysosporium were studied.Results show that the active Pb ions with high...The transformation behaviors of Pb fractions during composting of Pb-polluted waste without inoculants and with the inoculants of Phanerochaete chrysosporium were studied.Results show that the active Pb ions with high toxicity and transferability are transformed into the inactive Pb with low toxicity and transferability,confirming that Pb ions can be efficiently immobilized during composting without or with the inoculants.The soluble-exchangeable Pb in composting without inoculants reaches 49.0 mg/kg at day 60,while that with the inoculants is reduced to 0 mg/kg dry mass compost.The higher contents of organic-bound Pb (59.0 mg/kg)and residual Pb(69.2 mg/kg)with low toxicity are found after 60-day composting with inoculants,compared with those without inoculants.The above data indicate the better immobilization effect of Pb and the greater alleviation of Pb hazards in composting with the inoculants of Phanerochaete chrysosporium than without inoculants,which may be due to the more microbial biomass and the higher pH value in composting of Pb-polluted waste with inoculants.展开更多
The present paper investigates the existence of chaos in a non-autonomous fractional-order micro-electromechanical resonator system（FOMEMRS）.Using the maximal Lyapunov exponent criterion,we show that the FOMEMRS exh...The present paper investigates the existence of chaos in a non-autonomous fractional-order micro-electromechanical resonator system（FOMEMRS）.Using the maximal Lyapunov exponent criterion,we show that the FOMEMRS exhibits chaos.Strange attractors of the system are plotted to validate its chaotic behavior.Afterward,a novel fractional finite-time controller is introduced to suppress the chaos of the FOMEMRS with model uncertainties and external disturbances in a given finite time.Using the latest version of the fractional Lyapunov theory,the finite time stability and robustness of the proposed scheme are proved.Finally,we present some computer simulations to illustrate the usefulness and applicability of the proposed method.展开更多
For the purpose of investigating the nonlinear dynamics of the system,a fractional-order Chua's circuit based on the memristor deriving from the integer-order counterparts is provided. Firstly,according to the Lya...For the purpose of investigating the nonlinear dynamics of the system,a fractional-order Chua's circuit based on the memristor deriving from the integer-order counterparts is provided. Firstly,according to the Lyapunov's indirect method,the stability analysis of the memristive system is made,and it shows that when the fractional-orders parameter of memristive system passes a critical value,the system loses the stability and bifurcation occurs. Then the bifurcation and chaos behaviors of fractional-order memristive system are show n using bifurcation diagrams w ith varying fractional orders of the system and other parameters. Furthermore,the chaotic behaviors of memristive chaotic system are proved by the waveform,phase plot and largest Lyapunov exponent diagram. Finally,theoretical results are illustrated and validated with the given numerical simulations.展开更多
The three-parameter Petal-Teja equation of state coupled with a characterization proceduref0r C<sub>7+</sub>-fraction based on gamma distribution function was employed to predict the phase behaviorof eight...The three-parameter Petal-Teja equation of state coupled with a characterization proceduref0r C<sub>7+</sub>-fraction based on gamma distribution function was employed to predict the phase behaviorof eight gas condensates.The lumping of the subdivided single carbon number（SCN）hydrocarbons inthe plus-fraction and the choice of empirical correlations for calculating the critical properties andacentric factor of SCN hydrocarbons were discussed.展开更多
Heat transfer at the metal-die interface has a great influence on the solidification process and casting structure. As thin-wall components are extensively produced by high pressure die casting process(HPDC), the B390...Heat transfer at the metal-die interface has a great influence on the solidification process and casting structure. As thin-wall components are extensively produced by high pressure die casting process(HPDC), the B390 alloy finger-plate casting was cast against an H13 steel die on a cold-chamber HPDC machine. The interfacial heat transfer behavior at different positions of the die was carefully studied using an inverse approach based on the temperature measurements inside the die. Furthermore, the filling process and the solidification rate in different finger-plates were also given to explain the distribution of interfacial heat flux(q) and interfacial heat transfer coefficient(h). Measurement results at the side of sprue indicates that qmax and hmax could reach 9.2 MW·m^(-2) and 64.3 kW ·m^(-2)·K^(-1), respectively. The simulation of melt flow in the die reveals that the thinnest(T_1) finger plate could accelerate the melt flow from 50 m·s^(-1) to 110 m·s^(-1). Due to this high velocity, the interfacial heat flux at the end of T_1 could firstly reach a highest value 7.92 MW·m^(-2) among the ends of T_n(n=2,3,4,5). In addition, the q_(max) and h_(max) values of T_2, T_4 and T_5 finger-plates increase with the increasing thickness of the finger plate. Finally, at the rapid decreasing stage of interfacial heat transfer coefficient(h), the decreasing rate of h has an exponential relationship with the increasing rate of solid fraction(f).展开更多
The Tuha vacuum residue(>500℃)was separated into 7 narrow fractions by Supercritical Fluid Extraction and Fractionation(SFEF). The properties of all fractions and the vacuum residue were analyzed, and a characteri...The Tuha vacuum residue(>500℃)was separated into 7 narrow fractions by Supercritical Fluid Extraction and Fractionation(SFEF). The properties of all fractions and the vacuum residue were analyzed, and a characterization index for heavy oil, K H , was proposed to characterize the fractions which were used as the feedstock for FCC. The catalytic cracking reaction was carried out in an elaborately designed reactor system using CC-20D(QD)catalyst. The experimental results showed that SFEF had a good separation efficiency for vacuum residue and the fraction became worse with the increasing of extraction rate for FCC. The industrial way of residue oil for FCC was advanced on the base of the test results.展开更多
基金Project(50808073)supported by the National Natural Science Foundation of ChinaProject(2005CB724203)supported by the National Basic Research Program of China+1 种基金Project(2007)supported by the Program for Changjiang Scholars and Innovative Research Team in University,ChinaProject(2007185)supported by the Environmental Protection Technology Research Program of Hunan Province,China
文摘The transformation behaviors of Pb fractions during composting of Pb-polluted waste without inoculants and with the inoculants of Phanerochaete chrysosporium were studied.Results show that the active Pb ions with high toxicity and transferability are transformed into the inactive Pb with low toxicity and transferability,confirming that Pb ions can be efficiently immobilized during composting without or with the inoculants.The soluble-exchangeable Pb in composting without inoculants reaches 49.0 mg/kg at day 60,while that with the inoculants is reduced to 0 mg/kg dry mass compost.The higher contents of organic-bound Pb (59.0 mg/kg)and residual Pb(69.2 mg/kg)with low toxicity are found after 60-day composting with inoculants,compared with those without inoculants.The above data indicate the better immobilization effect of Pb and the greater alleviation of Pb hazards in composting with the inoculants of Phanerochaete chrysosporium than without inoculants,which may be due to the more microbial biomass and the higher pH value in composting of Pb-polluted waste with inoculants.
文摘The present paper investigates the existence of chaos in a non-autonomous fractional-order micro-electromechanical resonator system（FOMEMRS）.Using the maximal Lyapunov exponent criterion,we show that the FOMEMRS exhibits chaos.Strange attractors of the system are plotted to validate its chaotic behavior.Afterward,a novel fractional finite-time controller is introduced to suppress the chaos of the FOMEMRS with model uncertainties and external disturbances in a given finite time.Using the latest version of the fractional Lyapunov theory,the finite time stability and robustness of the proposed scheme are proved.Finally,we present some computer simulations to illustrate the usefulness and applicability of the proposed method.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61201227)the Funding of China Scholarship Council,the Natural Science Foundation of Anhui Province(Grant No.1208085M F93)the 211 Innovation Team of Anhui University(Grant Nos.KJTD007A and KJTD001B)
文摘For the purpose of investigating the nonlinear dynamics of the system,a fractional-order Chua's circuit based on the memristor deriving from the integer-order counterparts is provided. Firstly,according to the Lyapunov's indirect method,the stability analysis of the memristive system is made,and it shows that when the fractional-orders parameter of memristive system passes a critical value,the system loses the stability and bifurcation occurs. Then the bifurcation and chaos behaviors of fractional-order memristive system are show n using bifurcation diagrams w ith varying fractional orders of the system and other parameters. Furthermore,the chaotic behaviors of memristive chaotic system are proved by the waveform,phase plot and largest Lyapunov exponent diagram. Finally,theoretical results are illustrated and validated with the given numerical simulations.
文摘The three-parameter Petal-Teja equation of state coupled with a characterization proceduref0r C<sub>7+</sub>-fraction based on gamma distribution function was employed to predict the phase behaviorof eight gas condensates.The lumping of the subdivided single carbon number（SCN）hydrocarbons inthe plus-fraction and the choice of empirical correlations for calculating the critical properties andacentric factor of SCN hydrocarbons were discussed.
基金financially supported by the class General Financial Grant from the China Postdoctoral Science Foundation(No.2015M580093)the National Nature Science Foundation of China(No.20151301587)the National Major Science and Technology Program of China(No.2012ZX04012011)
文摘Heat transfer at the metal-die interface has a great influence on the solidification process and casting structure. As thin-wall components are extensively produced by high pressure die casting process(HPDC), the B390 alloy finger-plate casting was cast against an H13 steel die on a cold-chamber HPDC machine. The interfacial heat transfer behavior at different positions of the die was carefully studied using an inverse approach based on the temperature measurements inside the die. Furthermore, the filling process and the solidification rate in different finger-plates were also given to explain the distribution of interfacial heat flux(q) and interfacial heat transfer coefficient(h). Measurement results at the side of sprue indicates that qmax and hmax could reach 9.2 MW·m^(-2) and 64.3 kW ·m^(-2)·K^(-1), respectively. The simulation of melt flow in the die reveals that the thinnest(T_1) finger plate could accelerate the melt flow from 50 m·s^(-1) to 110 m·s^(-1). Due to this high velocity, the interfacial heat flux at the end of T_1 could firstly reach a highest value 7.92 MW·m^(-2) among the ends of T_n(n=2,3,4,5). In addition, the q_(max) and h_(max) values of T_2, T_4 and T_5 finger-plates increase with the increasing thickness of the finger plate. Finally, at the rapid decreasing stage of interfacial heat transfer coefficient(h), the decreasing rate of h has an exponential relationship with the increasing rate of solid fraction(f).
文摘The Tuha vacuum residue(>500℃)was separated into 7 narrow fractions by Supercritical Fluid Extraction and Fractionation(SFEF). The properties of all fractions and the vacuum residue were analyzed, and a characterization index for heavy oil, K H , was proposed to characterize the fractions which were used as the feedstock for FCC. The catalytic cracking reaction was carried out in an elaborately designed reactor system using CC-20D(QD)catalyst. The experimental results showed that SFEF had a good separation efficiency for vacuum residue and the fraction became worse with the increasing of extraction rate for FCC. The industrial way of residue oil for FCC was advanced on the base of the test results.
