A new method based on phononic crystals is presented to detect the concentration of heavy water(D_(2)O)in an H_(2)O-D_(2)O mixture.Results have been obtained and analyzed in the concentration range of 0%-10%and 90%-10...A new method based on phononic crystals is presented to detect the concentration of heavy water(D_(2)O)in an H_(2)O-D_(2)O mixture.Results have been obtained and analyzed in the concentration range of 0%-10%and 90%-100%D_(2)O.A proposed structure of tungsten scatterers in an aluminum host is studied.In order to detect the target material,a cavity region is considered as a sound wave resonator in which the target material with different concentrations of D_(2)O is embedded.By changing the concentration of D_(2)O in the H_(2)O-D_(2)O mixture,the resonance frequency undergoes a frequency shift.Each 1%change in D_(2)O concentration in the H_(2)O-D_(2)O mixture causes a frequency change of about 120 Hz.The finite element method is used as the numerical method to calculate and analyze the natural frequencies and transmission spectra of the proposed sensor.The performance evaluation index shows a high Q factor up to 1475758 and a high sensitivity up to 13075,which are acceptable values for sensing purposes.The other figures of merit related to the detection performance also indicate high-quality performance of the designed sensor.展开更多
A simple model is described to simulate kinetic processes in dielectric barrier dis-charges for O2/NOx mixtures. A threshold of ozone production found experimentally is confirmedby the calculations of this modeling, a...A simple model is described to simulate kinetic processes in dielectric barrier dis-charges for O2/NOx mixtures. A threshold of ozone production found experimentally is confirmedby the calculations of this modeling, and the underiying chemical reaction mechanisms are dis-cussed. It is also found that the effects of diffusion processes in the period of the lifetime of Oatoms are not important to microdischarge channels with a large radius, i.e. larger than l50 μm.展开更多
The ferrites of Cuo-ZnO-Fe2o3 solid solution series near the molar ratio of ZnxCu1-x were prepared by direct heating of their coprecipitated hydroxides using NH4OH as precipitating agent where x=0.0, 0.2, 0.5, 0.8 and...The ferrites of Cuo-ZnO-Fe2o3 solid solution series near the molar ratio of ZnxCu1-x were prepared by direct heating of their coprecipitated hydroxides using NH4OH as precipitating agent where x=0.0, 0.2, 0.5, 0.8 and 1.0. Additional amounts of Cu and Zn sulphates were added to compensate the loss during the coprecipitation of the hydroxides. The ferritized samples were characterized by chemical analysis, XRD. DTA, TGA and SEM. XRD of both Zn0.2Cu0.8Fe2O4 and Zn0.5Cu0.5 Fe2O4 that indicates the formation of a heterogeneous ferrite material of ZnFe2O4 and CuFe2O4 mixed with variable amounts of α-Fe2O3. Zn and Cu ferrites were observed only in Zn0.8Cu0.2Fe2O4.From TGA-time relation, the activation energy of the different transformation phases were calculated. It is found that, the activation energy of ZnFe2O4 is slightly equal to 3/2 of that for CuFe2O4. Dielectric measurements show that the electrical behaviour depends on the ordering and disordering of the phases.展开更多
A solid ternary mixture consisting of NaF,silicon and one metal oxide such as La2O3,CeO2,Pr6O11,Nd2O3,and Y2O3 was prepared and usedas de-fluorinated reagent for CF4 decomposition.The results show that 90% conversion ...A solid ternary mixture consisting of NaF,silicon and one metal oxide such as La2O3,CeO2,Pr6O11,Nd2O3,and Y2O3 was prepared and usedas de-fluorinated reagent for CF4 decomposition.The results show that 90% conversion of CF4 can be reached initially over NaF-Si-La2O3,NaF-Si-CeO2,NaF-Si-Nd2O3,and NaF-Si-Y2O3 at 850 C.The fresh and used reagents were characterized using XRD and XPS techniques.It was found that the active components of NaF and metal oxides in NaF-Si-CeO2,NaF-Si-Pr6O11,NaF-Si-Nd2O3,and NaF-Si-Y2O3 weretransformed into inert phases of mixed metal fluorides and silicates,respectively,resulting in an ineffective utilization of these de-fluorinatedreagents,whereas no inert phases from NaF and La2O3 can be observed in the used NaF-Si-La2O3,indicating the NaF-Si-La2O3 reagent couldbe utilized more efficiently than the other reagents in CF4 decomposition.展开更多
Phase behavior of carbon dioxide/water binary mixtures plays an important role in various CO2-based industry processes. This work aims to screen a thermodynamic model out of a number of promising candidate models to c...Phase behavior of carbon dioxide/water binary mixtures plays an important role in various CO2-based industry processes. This work aims to screen a thermodynamic model out of a number of promising candidate models to capture the vapor–liquid equilibria, liquid–liquid equilibria, and phase densities of CO2/H2O mixtures. A comprehensive analysis reveals that Peng–Robinson equation of state (PR EOS) (Peng and Robinson 1976), Twu α function (Twu et al. 1991), Huron–Vidal mixing rule (Huron and Vidal 1979), and Abudour et al. (2013) volume translation model (Abudour et al. 2013) is the best model among the ones examined;it yields average absolute percentage errors of 5.49% and 2.90% in reproducing the experimental phase composition data and density data collected in the literature. After achieving the reliable modeling of phase compositions and densities, a new IFT correlation based on the aforementioned PR EOS model is proposed through a nonlinear regression of the measured IFT data collected from the literature over 278.15–477.59 K and 1.00–1200.96 bar. Although the newly proposed IFT correlation only slightly improves the prediction accuracy yielded by the refitted Chen and Yang (2019)’s correlation (Chen and Yang 2019), the proposed correlation avoids the inconsistent predictions present in Chen and Yang (2019)’s correlation and yields smooth IFT predictions.展开更多
A glass crusher was developed to improve the waste glass crushing process.The waste glass was recycled,crushed and sieved to different particle sizes as glass aggregates,and the surface of glass aggregates was treated...A glass crusher was developed to improve the waste glass crushing process.The waste glass was recycled,crushed and sieved to different particle sizes as glass aggregates,and the surface of glass aggregates was treated by nano-Fe2O3 suspension to improve the anti-striping property.The glasphalt mixture made by partly replacing mineral aggregates with glass aggregates was designed and evaluated.The sizes of glass aggregates were selected to be 2.36 and 4.75 mm,and the optimum concentration of nano-Fe2O3 suspension was determined to be 10%.The optimum asphalt content(OAC)was determined by the Marshall method and the glass aggregate content.The influence of the glass aggregate content on the technical properties of glasphalt mixtures were analyzed by the rutting test,three-point bending test,freeze-thaw splitting test and skid resistance test.The results show that the optimal content of glass aggregates and OAC are recommended to be 15%and 4.4%,respectively.These environmentally-friendly glasphalt mixtures can solve the problem of environmental pollution caused by waste glass,as well as reducing the cost of pavement materials and construction.展开更多
In this work, a two-dimensional fluid model has been employed to study the characteristics of Ar/O2 radio frequency（RF） inductively coupled plasma discharges. The emphasis of this work has been put on the influence ...In this work, a two-dimensional fluid model has been employed to study the characteristics of Ar/O2 radio frequency（RF） inductively coupled plasma discharges. The emphasis of this work has been put on the influence of the external parameters（i.e., the RF power, the pressure, and the Ar/O2 gas ratio） on the plasma properties. The numerical results show that the RF power has a significant influence on the amplitude of the plasma density rather than on the spatial distribution.However, the pressure and the Ar/O2 gas ratio affect not only the amplitude of the plasma density, but also the spatial uniformity. Finally, the comparison between the simulation results and the experimental data has been made at different gas pressures and oxygen contents, and a good agreement has been achieved.展开更多
文摘A new method based on phononic crystals is presented to detect the concentration of heavy water(D_(2)O)in an H_(2)O-D_(2)O mixture.Results have been obtained and analyzed in the concentration range of 0%-10%and 90%-100%D_(2)O.A proposed structure of tungsten scatterers in an aluminum host is studied.In order to detect the target material,a cavity region is considered as a sound wave resonator in which the target material with different concentrations of D_(2)O is embedded.By changing the concentration of D_(2)O in the H_(2)O-D_(2)O mixture,the resonance frequency undergoes a frequency shift.Each 1%change in D_(2)O concentration in the H_(2)O-D_(2)O mixture causes a frequency change of about 120 Hz.The finite element method is used as the numerical method to calculate and analyze the natural frequencies and transmission spectra of the proposed sensor.The performance evaluation index shows a high Q factor up to 1475758 and a high sensitivity up to 13075,which are acceptable values for sensing purposes.The other figures of merit related to the detection performance also indicate high-quality performance of the designed sensor.
文摘A simple model is described to simulate kinetic processes in dielectric barrier dis-charges for O2/NOx mixtures. A threshold of ozone production found experimentally is confirmedby the calculations of this modeling, and the underiying chemical reaction mechanisms are dis-cussed. It is also found that the effects of diffusion processes in the period of the lifetime of Oatoms are not important to microdischarge channels with a large radius, i.e. larger than l50 μm.
文摘The ferrites of Cuo-ZnO-Fe2o3 solid solution series near the molar ratio of ZnxCu1-x were prepared by direct heating of their coprecipitated hydroxides using NH4OH as precipitating agent where x=0.0, 0.2, 0.5, 0.8 and 1.0. Additional amounts of Cu and Zn sulphates were added to compensate the loss during the coprecipitation of the hydroxides. The ferritized samples were characterized by chemical analysis, XRD. DTA, TGA and SEM. XRD of both Zn0.2Cu0.8Fe2O4 and Zn0.5Cu0.5 Fe2O4 that indicates the formation of a heterogeneous ferrite material of ZnFe2O4 and CuFe2O4 mixed with variable amounts of α-Fe2O3. Zn and Cu ferrites were observed only in Zn0.8Cu0.2Fe2O4.From TGA-time relation, the activation energy of the different transformation phases were calculated. It is found that, the activation energy of ZnFe2O4 is slightly equal to 3/2 of that for CuFe2O4. Dielectric measurements show that the electrical behaviour depends on the ordering and disordering of the phases.
基金supported by the National Natural Science Foundation of China (No. 20976149)
文摘A solid ternary mixture consisting of NaF,silicon and one metal oxide such as La2O3,CeO2,Pr6O11,Nd2O3,and Y2O3 was prepared and usedas de-fluorinated reagent for CF4 decomposition.The results show that 90% conversion of CF4 can be reached initially over NaF-Si-La2O3,NaF-Si-CeO2,NaF-Si-Nd2O3,and NaF-Si-Y2O3 at 850 C.The fresh and used reagents were characterized using XRD and XPS techniques.It was found that the active components of NaF and metal oxides in NaF-Si-CeO2,NaF-Si-Pr6O11,NaF-Si-Nd2O3,and NaF-Si-Y2O3 weretransformed into inert phases of mixed metal fluorides and silicates,respectively,resulting in an ineffective utilization of these de-fluorinatedreagents,whereas no inert phases from NaF and La2O3 can be observed in the used NaF-Si-La2O3,indicating the NaF-Si-La2O3 reagent couldbe utilized more efficiently than the other reagents in CF4 decomposition.
文摘Phase behavior of carbon dioxide/water binary mixtures plays an important role in various CO2-based industry processes. This work aims to screen a thermodynamic model out of a number of promising candidate models to capture the vapor–liquid equilibria, liquid–liquid equilibria, and phase densities of CO2/H2O mixtures. A comprehensive analysis reveals that Peng–Robinson equation of state (PR EOS) (Peng and Robinson 1976), Twu α function (Twu et al. 1991), Huron–Vidal mixing rule (Huron and Vidal 1979), and Abudour et al. (2013) volume translation model (Abudour et al. 2013) is the best model among the ones examined;it yields average absolute percentage errors of 5.49% and 2.90% in reproducing the experimental phase composition data and density data collected in the literature. After achieving the reliable modeling of phase compositions and densities, a new IFT correlation based on the aforementioned PR EOS model is proposed through a nonlinear regression of the measured IFT data collected from the literature over 278.15–477.59 K and 1.00–1200.96 bar. Although the newly proposed IFT correlation only slightly improves the prediction accuracy yielded by the refitted Chen and Yang (2019)’s correlation (Chen and Yang 2019), the proposed correlation avoids the inconsistent predictions present in Chen and Yang (2019)’s correlation and yields smooth IFT predictions.
基金The project was supported by the National Key Basic Research Program of China(973)(2012CB720100)National Natural Science Foundation of China(20973124)~~
基金The Project of the Department of Science&Technology of Shaanxi Province(No.2016KJXX-69,2016ZDJC-24,2017KCT-13)China Postdoctoral Science Foundation(No.2017M620434)the Special Fund for Basic Scientific Research of Central College of Chang’an University(No.310821153502,310821173501)
文摘A glass crusher was developed to improve the waste glass crushing process.The waste glass was recycled,crushed and sieved to different particle sizes as glass aggregates,and the surface of glass aggregates was treated by nano-Fe2O3 suspension to improve the anti-striping property.The glasphalt mixture made by partly replacing mineral aggregates with glass aggregates was designed and evaluated.The sizes of glass aggregates were selected to be 2.36 and 4.75 mm,and the optimum concentration of nano-Fe2O3 suspension was determined to be 10%.The optimum asphalt content(OAC)was determined by the Marshall method and the glass aggregate content.The influence of the glass aggregate content on the technical properties of glasphalt mixtures were analyzed by the rutting test,three-point bending test,freeze-thaw splitting test and skid resistance test.The results show that the optimal content of glass aggregates and OAC are recommended to be 15%and 4.4%,respectively.These environmentally-friendly glasphalt mixtures can solve the problem of environmental pollution caused by waste glass,as well as reducing the cost of pavement materials and construction.
基金Project supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China(Grant No.2011ZX02403-001)the National Natural Science Foundation of China(Grant No.11205025)
文摘In this work, a two-dimensional fluid model has been employed to study the characteristics of Ar/O2 radio frequency（RF） inductively coupled plasma discharges. The emphasis of this work has been put on the influence of the external parameters（i.e., the RF power, the pressure, and the Ar/O2 gas ratio） on the plasma properties. The numerical results show that the RF power has a significant influence on the amplitude of the plasma density rather than on the spatial distribution.However, the pressure and the Ar/O2 gas ratio affect not only the amplitude of the plasma density, but also the spatial uniformity. Finally, the comparison between the simulation results and the experimental data has been made at different gas pressures and oxygen contents, and a good agreement has been achieved.
