Biological aerated filters have many advantages such as small volume and high treatment efficiency. This research focused on sewage treatment performance of integrated biological aerated filter (IBAF) under different ...Biological aerated filters have many advantages such as small volume and high treatment efficiency. This research focused on sewage treatment performance of integrated biological aerated filter (IBAF) under different conditions such as aeration, hydraulic retention time and the height of fillers layer, to identify the turn of marked affecting factor of removal performance through orthogonal experiments, optimize the function parameter of IBAF, reveal the regularity of sewage treatment of IBAF under different conditions, and adopt suitable measures to guarantee excess water quality of IBAF.展开更多
The carbon fiber reinforced composite is a new type of composite material with an excellent property in strength and elastic modulus,and has found extensive applications in aerospace,energy,automotive industry and so ...The carbon fiber reinforced composite is a new type of composite material with an excellent property in strength and elastic modulus,and has found extensive applications in aerospace,energy,automotive industry and so on.However,this composite has a strict requirement on processing techniques,for example,brittle damage or delamination often exists in conventional processing techniques.Abrasive water jet machining technology is a new type of green machining technique with distinct advantages such as high-energy and thermal distortion free.The use of abrasive water jet technique to process carbon fiber composite materials has become a popular trend since it can significantly improve the processing accuracy and surface quality of carbon fiber composite materials.However,there are too many parameters that affect the quality of an abrasive water jet machining.At present,few studies are carried out on the parameter optimization of such a machining process,which leads to the unstable quality of surface processing.In this paper,orthogonal design of experiment and regression analysis were employed to establish the empirical model between cutting surface roughness and machining process parameters.Then a verified model was used to optimize the machining process parameters for abrasive water jet cutting carbon fiber reinforced composites.展开更多
The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation sp...The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation speed. Experimental results show that the spindle rotation speed is the most influential factor. The thrust andthe torque decrease under the condition of high rotation rate. With the decrease of the feed speed, the thrust and the torque decrease. But the effect of the feed speed is less than that of the spindle rotation rate. Moreover, the effect of drill materials on the thrust and the torque is more notable than that of the drill geometries and the feed speed. The thrust is greatly affected by the feed speed while the torque is obviously affected by drill geometries.展开更多
Aiming at the independent development of tracked vehicles,it is urgent to improve its mobility,passability and ride comfort,a new type of flexible road wheel with a“wheel-hinge-hub”combined structure is proposed in ...Aiming at the independent development of tracked vehicles,it is urgent to improve its mobility,passability and ride comfort,a new type of flexible road wheel with a“wheel-hinge-hub”combined structure is proposed in this study.The vibration model characteristics of the flexible road wheel were studied by the combination of numerical simulation and experiments.The superelasticity of rubber is obtained through uniaxial tensile experiment of the material and a detail three-dimensional nolinear finite element model of the flexible road wheel is established through finite element software ABAQUS.The free vibration equation of the flexible road wheel is solved by Lanczos vector direct superposition method,and its predicted modes and natural frequencies are compared with experimental results,which verifies the accuracy and reliability of the established finite element model.On this basis,the effects of various key structural or material factors on the natural frequencies of the flexible road wheel are studied using orthogonal experimental design method.Besides,the vibration modal characteristics of the flexible road wheel are also compared with those of the rigid road wheel.The research results provide a theoretical basis for the vibration and noise reduction of flexible road wheel.展开更多
With ion implantation (N+, energy 10 keV and dosage 1.56×1015 N+cm-2), a high xylanase-producing strain Aspergillus niger N212 was selected. Based on an orthogonal experiment, an optimal fermentation condition wa...With ion implantation (N+, energy 10 keV and dosage 1.56×1015 N+cm-2), a high xylanase-producing strain Aspergillus niger N212 was selected. Based on an orthogonal experiment, an optimal fermentation condition was designed for this high-yield strain. The suitable medium was composed of 8% corncob; 1.0% wheat bran; 0.1%TWEEN20; 0.5% (NH4)2SO4; 0.5%NaNO3; 0.5%FeSO4, 7.5 × 10-4; MnSO4·H2O, 2.5 × 10-4; ZnSO4, 2.0 × 10-4; CoCl2, 3.0 × 10-4. At present, under our experiment condition, xylanase activity of Aspergillus niger N212 reached a level of 600 IU/ml, almost increased by 100% in xylanase production and the time of yielding xylanase was largely reduced to 12 h at 28℃.展开更多
a new strategy combining an expert system and improved genetic algorithms is presented for tuning proportional-integral-derivative （PID） parameters for petrochemical processes. This retains the advantages of genetic...a new strategy combining an expert system and improved genetic algorithms is presented for tuning proportional-integral-derivative （PID） parameters for petrochemical processes. This retains the advantages of genetic algorithms, namely rapid convergence and attainment of the global optimum. Utilization of an orthogonal experiment method solves the determination of the genetic factors. Combination with an expert system can make best use of the actual experience of the plant operators. Simulation results of typical process systems examples show a good control performance and robustness.展开更多
We focused on the optimization of corn-stalk skin flake-wood shaving composite technology. We studied the effects of material-mixture ratio, glue content, hot- pressing temperature, and hot-pressing time on the appear...We focused on the optimization of corn-stalk skin flake-wood shaving composite technology. We studied the effects of material-mixture ratio, glue content, hot- pressing temperature, and hot-pressing time on the appear- ance, physical, and mechanical properties of the composite by the orthogonal experiment method. Our findings yielded highly significant results in all three cases： the effects of the material-mixture ratio on 2 h of thickness swelling （2hTS） and the modulus of rupture （MOR）; the effects of glue con- tent on 2hTS, internal bond strength, and modulus of elas- ticity （MOE）; and the effects of hot-pressing temperature on MOR and MOE. Product optimization is achieved when the ratio of corn stalk skin flake to wood shaving is 3：7, the glue content is 12 %, the hot-pressing temperature is 150 ℃, and the hot-pressing time is 4.5 min.展开更多
To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain siz...To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain size of Li FeP O4/C decreases,and the impurities in Li Fe PO4/C composites reduce to a great extent. It makes great sense to the mass industrial production. The optimum synthesis conditions determined in this work are based on the orthogonal experiments. The samples synthesized in a scale of 500 g exhibit high purity,excellent electrochemical performance,high reaction activity,good reversibility,and low polarization level.The discharge capacities are 145,134,117,and 102 m Ah/g at the current densities of 0.1 C,0.2 C,0.5 C and1 C,respectively. This work puts forward a practical suggestion for mass producing environmental benign and low cost Li FeP O4/C as cathode materials of lithium ion batteries.展开更多
The stability of petroleum coke water slurry（PCWS） is currently a hot topic. The inherent relationship between yield stress and stability of bubble-PCWS was studied through orthogonal experiments and range analysis ...The stability of petroleum coke water slurry（PCWS） is currently a hot topic. The inherent relationship between yield stress and stability of bubble-PCWS was studied through orthogonal experiments and range analysis in this work. The results showed that the stability of bubble-PCWS was positively related to the yield stress and that the yield stress could be greatly impacted by the operation conditions during preparation of bubble-PCWS. The main factors affecting the yield stress of bubble-PCWS were solid concentration, aeration time and dosage of frother. However, the effects of aperture size of air distribution plates and type of frother on the yield stress were slight within the experimental range. The optimal conditions for the greatest yield stress were as follows： aeration time of 30 min, solid concentration of 65 wt%, frother dosage of0.030 wt% of the air-dried pulverized petroleum coke, aperture size of air distribution plate of 2-5 lm and AOS frother.The yield stress and the pour rate of bubble-PCWS under this optimum operation condition could reach maxima of more than 0.4 Pa and 96%, respectively.展开更多
To optimize cutting control parameters and provide scientific evidence for controlling cutting forces,cutting force modeling and cutting control parameter optimization are researched with one tool adopted to orbital d...To optimize cutting control parameters and provide scientific evidence for controlling cutting forces,cutting force modeling and cutting control parameter optimization are researched with one tool adopted to orbital drill holes in aluminum alloy 6061.Firstly,four cutting control parameters(tool rotation speed,tool revolution speed,axial feeding pitch and tool revolution radius)and affecting cutting forces are identified after orbital drilling kinematics analysis.Secondly,hybrid level orthogonal experiment method is utilized in modeling experiment.By nonlinear regression analysis,two quadratic prediction models for axial and radial forces are established,where the above four control parameters are used as input variables.Then,model accuracy and cutting control parameters are analyzed.Upon axial and radial forces models,two optimal combinations of cutting control parameters are obtained for processing a13mm hole,corresponding to the minimum axial force and the radial force respectively.Finally,each optimal combination is applied in verification experiment.The verification experiment results of cutting force are in good agreement with prediction model,which confirms accracy of the research method in practical production.展开更多
A new fluid bag buffer mechanism,which can provide large axial stiffness under the small displacement,is designed.The dynamic change laws of the mechanism stiffness and the internal pressure of the fluid bag are studi...A new fluid bag buffer mechanism,which can provide large axial stiffness under the small displacement,is designed.The dynamic change laws of the mechanism stiffness and the internal pressure of the fluid bag are studied when it is subjected to impact load.According to the protection performance for the flexible joint and the pressure change in the fluid bag during the impact process,the sensitivity of the geometric parameters of the fluid bag to the axial stiffness is analyzed by using the orthogonal experimental method,and the optimal parameter combination of the geometric parameters of the fluid bag under impact is obtained,leading to the displacement of the inner shell reduce by 41.4%.The results show that the internal pressure of the fluid bag is a rising process of oscillation and fluctuation.The sensitivity of the geometric parameters of the fluid bag to the displacement of the inner shell from high to low is as follows:Height H,radius r,wall thickness t,chamfer A.The correlation between the geometric parameters of the fluid bag and its internal pressure is:H is negatively correlated with the internal pressure,while the r,t,and A are positively correlated with the internal pressure.展开更多
Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of ox...Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of oxidative desulfurization under the electric field was compared with that of the single oxidative desulfurization method.The test results showed that the desulfurization reaction taking place under the electric field would be better than the traditional method.The desulfurization rate of crude oil could reach up to 77.06% at 115 ℃ at a distilled water amount of 10 m%,a desulfurizer dosage of 200 μg/g,and a demulsifier dosage of 50 μg/g.展开更多
A new process for preparing poly(phenylene sulfide amide, PPSA), which is by reaction of sulfur instead of sodium sulfide as S source with dichlorobenzamide (DCBA) and alkali in polar orga...A new process for preparing poly(phenylene sulfide amide, PPSA), which is by reaction of sulfur instead of sodium sulfide as S source with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure (called sulfur solution route), is reported in the present paper. The influences of polymerization time, molar ratio of precursors, catalyst and solvent upon the polymer were investigated. To seek the best parameters of polymerization, orthogonal design was employed in the experiments. The results indicate that the molar ratio of precursors is the most significant effect on both of viscosity and yield of the polymer. The suitable parameters for preparing the related polymer are presented. The polymer was characterized by IRspectrum, 1HNMRspectrum and Raman spectrum, etc.展开更多
A new type of refuse derived fuel (RDF) for pyrolysis and gasification was prepared from municipal solid waste (MSW) in the presence of a small quantity of coal by bindless high pressure technology at room temperature...A new type of refuse derived fuel (RDF) for pyrolysis and gasification was prepared from municipal solid waste (MSW) in the presence of a small quantity of coal by bindless high pressure technology at room temperature. The physicochemical property of RDF was tested. Orthogonal experiment method was used to optimize the process parameters using dropping strength (mechanical strength) and thermal stability of the RDF as indices for quality of RDF. The result shows that the mixture of MSW and coal with a total moisture ranging from 5% to 17% can be easily compressed into RDF briquettes at a pressure above 70 MPa. When the briquetting pressure is higher than 100 kN and moisture content is about 10%, the qualified RDF can be obtained. The orthogonal experiment shows that the moisture can greatly affect the mechanical strength of RDF, while all the technique parameters have no obvious influence on thermal stability of RDF. The optimal parameters are a shaping pressure of 106 MPa, a moisture content of 10%, and a coal content of 20%.展开更多
文摘Biological aerated filters have many advantages such as small volume and high treatment efficiency. This research focused on sewage treatment performance of integrated biological aerated filter (IBAF) under different conditions such as aeration, hydraulic retention time and the height of fillers layer, to identify the turn of marked affecting factor of removal performance through orthogonal experiments, optimize the function parameter of IBAF, reveal the regularity of sewage treatment of IBAF under different conditions, and adopt suitable measures to guarantee excess water quality of IBAF.
基金National High-Tech R&D Program of China(863 Program)(2015AA043401)。
文摘The carbon fiber reinforced composite is a new type of composite material with an excellent property in strength and elastic modulus,and has found extensive applications in aerospace,energy,automotive industry and so on.However,this composite has a strict requirement on processing techniques,for example,brittle damage or delamination often exists in conventional processing techniques.Abrasive water jet machining technology is a new type of green machining technique with distinct advantages such as high-energy and thermal distortion free.The use of abrasive water jet technique to process carbon fiber composite materials has become a popular trend since it can significantly improve the processing accuracy and surface quality of carbon fiber composite materials.However,there are too many parameters that affect the quality of an abrasive water jet machining.At present,few studies are carried out on the parameter optimization of such a machining process,which leads to the unstable quality of surface processing.In this paper,orthogonal design of experiment and regression analysis were employed to establish the empirical model between cutting surface roughness and machining process parameters.Then a verified model was used to optimize the machining process parameters for abrasive water jet cutting carbon fiber reinforced composites.
文摘The thrust and the torque of various carbide drills are studied for the high-speed drilling of fiber reinforced epoxy composites. The orthogonal experiment is carried out with different feed speeds at high rotation speed. Experimental results show that the spindle rotation speed is the most influential factor. The thrust andthe torque decrease under the condition of high rotation rate. With the decrease of the feed speed, the thrust and the torque decrease. But the effect of the feed speed is less than that of the spindle rotation rate. Moreover, the effect of drill materials on the thrust and the torque is more notable than that of the drill geometries and the feed speed. The thrust is greatly affected by the feed speed while the torque is obviously affected by drill geometries.
基金the National Natural Science Foundation of China[grant numbers 11672127,51605215]the Advance Research Special Technology Project of Army Equipment[grant number AGA19001]+2 种基金the Army Research and Technology Project[grant number AQA19001],the Innovation Fund Project of China Aerospace 1st Academy[grant number CHC20001]the Special funded project of China Postdoctoral Science Foundation[grant number 2019T120450]the Fundamental Research Funds for the Central Universities[grant number NP2020407].
文摘Aiming at the independent development of tracked vehicles,it is urgent to improve its mobility,passability and ride comfort,a new type of flexible road wheel with a“wheel-hinge-hub”combined structure is proposed in this study.The vibration model characteristics of the flexible road wheel were studied by the combination of numerical simulation and experiments.The superelasticity of rubber is obtained through uniaxial tensile experiment of the material and a detail three-dimensional nolinear finite element model of the flexible road wheel is established through finite element software ABAQUS.The free vibration equation of the flexible road wheel is solved by Lanczos vector direct superposition method,and its predicted modes and natural frequencies are compared with experimental results,which verifies the accuracy and reliability of the established finite element model.On this basis,the effects of various key structural or material factors on the natural frequencies of the flexible road wheel are studied using orthogonal experimental design method.Besides,the vibration modal characteristics of the flexible road wheel are also compared with those of the rigid road wheel.The research results provide a theoretical basis for the vibration and noise reduction of flexible road wheel.
文摘With ion implantation (N+, energy 10 keV and dosage 1.56×1015 N+cm-2), a high xylanase-producing strain Aspergillus niger N212 was selected. Based on an orthogonal experiment, an optimal fermentation condition was designed for this high-yield strain. The suitable medium was composed of 8% corncob; 1.0% wheat bran; 0.1%TWEEN20; 0.5% (NH4)2SO4; 0.5%NaNO3; 0.5%FeSO4, 7.5 × 10-4; MnSO4·H2O, 2.5 × 10-4; ZnSO4, 2.0 × 10-4; CoCl2, 3.0 × 10-4. At present, under our experiment condition, xylanase activity of Aspergillus niger N212 reached a level of 600 IU/ml, almost increased by 100% in xylanase production and the time of yielding xylanase was largely reduced to 12 h at 28℃.
文摘a new strategy combining an expert system and improved genetic algorithms is presented for tuning proportional-integral-derivative （PID） parameters for petrochemical processes. This retains the advantages of genetic algorithms, namely rapid convergence and attainment of the global optimum. Utilization of an orthogonal experiment method solves the determination of the genetic factors. Combination with an expert system can make best use of the actual experience of the plant operators. Simulation results of typical process systems examples show a good control performance and robustness.
文摘We focused on the optimization of corn-stalk skin flake-wood shaving composite technology. We studied the effects of material-mixture ratio, glue content, hot- pressing temperature, and hot-pressing time on the appear- ance, physical, and mechanical properties of the composite by the orthogonal experiment method. Our findings yielded highly significant results in all three cases： the effects of the material-mixture ratio on 2 h of thickness swelling （2hTS） and the modulus of rupture （MOR）; the effects of glue con- tent on 2hTS, internal bond strength, and modulus of elas- ticity （MOE）; and the effects of hot-pressing temperature on MOR and MOE. Product optimization is achieved when the ratio of corn stalk skin flake to wood shaving is 3：7, the glue content is 12 %, the hot-pressing temperature is 150 ℃, and the hot-pressing time is 4.5 min.
基金supported by the National Science Foundation of China(grant no.21206099)
文摘To effectively solve the agglomeration problems in the solid state reaction process,pre-adding glucose is adopted to the synthesis of Li Fe PO4/C energy materials using Fe–P waste slag. The average particle grain size of Li FeP O4/C decreases,and the impurities in Li Fe PO4/C composites reduce to a great extent. It makes great sense to the mass industrial production. The optimum synthesis conditions determined in this work are based on the orthogonal experiments. The samples synthesized in a scale of 500 g exhibit high purity,excellent electrochemical performance,high reaction activity,good reversibility,and low polarization level.The discharge capacities are 145,134,117,and 102 m Ah/g at the current densities of 0.1 C,0.2 C,0.5 C and1 C,respectively. This work puts forward a practical suggestion for mass producing environmental benign and low cost Li FeP O4/C as cathode materials of lithium ion batteries.
基金he financial supports from National Natural Science Foundation of China (Grant No. 51506185)Zhejiang Provincial Natural Science Foundation of China (Grant No. LQ15E060002)
文摘The stability of petroleum coke water slurry（PCWS） is currently a hot topic. The inherent relationship between yield stress and stability of bubble-PCWS was studied through orthogonal experiments and range analysis in this work. The results showed that the stability of bubble-PCWS was positively related to the yield stress and that the yield stress could be greatly impacted by the operation conditions during preparation of bubble-PCWS. The main factors affecting the yield stress of bubble-PCWS were solid concentration, aeration time and dosage of frother. However, the effects of aperture size of air distribution plates and type of frother on the yield stress were slight within the experimental range. The optimal conditions for the greatest yield stress were as follows： aeration time of 30 min, solid concentration of 65 wt%, frother dosage of0.030 wt% of the air-dried pulverized petroleum coke, aperture size of air distribution plate of 2-5 lm and AOS frother.The yield stress and the pour rate of bubble-PCWS under this optimum operation condition could reach maxima of more than 0.4 Pa and 96%, respectively.
基金Supported by the National Natural Science Foundation of China(50975141)the Aviation Science Fund(20091652018,2010352005)the National Science and Technology Major Project of the Ministry of Science and Technology of China(2012ZX04003031-4)
文摘To optimize cutting control parameters and provide scientific evidence for controlling cutting forces,cutting force modeling and cutting control parameter optimization are researched with one tool adopted to orbital drill holes in aluminum alloy 6061.Firstly,four cutting control parameters(tool rotation speed,tool revolution speed,axial feeding pitch and tool revolution radius)and affecting cutting forces are identified after orbital drilling kinematics analysis.Secondly,hybrid level orthogonal experiment method is utilized in modeling experiment.By nonlinear regression analysis,two quadratic prediction models for axial and radial forces are established,where the above four control parameters are used as input variables.Then,model accuracy and cutting control parameters are analyzed.Upon axial and radial forces models,two optimal combinations of cutting control parameters are obtained for processing a13mm hole,corresponding to the minimum axial force and the radial force respectively.Finally,each optimal combination is applied in verification experiment.The verification experiment results of cutting force are in good agreement with prediction model,which confirms accracy of the research method in practical production.
基金supported by the Fun⁃damental Scientific Research Business Expenses of Central Universities(No.NJ2020024).
文摘A new fluid bag buffer mechanism,which can provide large axial stiffness under the small displacement,is designed.The dynamic change laws of the mechanism stiffness and the internal pressure of the fluid bag are studied when it is subjected to impact load.According to the protection performance for the flexible joint and the pressure change in the fluid bag during the impact process,the sensitivity of the geometric parameters of the fluid bag to the axial stiffness is analyzed by using the orthogonal experimental method,and the optimal parameter combination of the geometric parameters of the fluid bag under impact is obtained,leading to the displacement of the inner shell reduce by 41.4%.The results show that the internal pressure of the fluid bag is a rising process of oscillation and fluctuation.The sensitivity of the geometric parameters of the fluid bag to the displacement of the inner shell from high to low is as follows:Height H,radius r,wall thickness t,chamfer A.The correlation between the geometric parameters of the fluid bag and its internal pressure is:H is negatively correlated with the internal pressure,while the r,t,and A are positively correlated with the internal pressure.
基金financial supports from the Science and Technology Office of Liaoning Province (Project number:2008403001)the Liaoning Provincial Office of Education for Innovation Team (Project number:2009T002)
文摘Oxidative desulfurization (ODS) of Azeri crude oil was studied under the electric field.By means of orthogonal experiments,the optimum conditions for desulfurization of crude oil were identified,while the effect of oxidative desulfurization under the electric field was compared with that of the single oxidative desulfurization method.The test results showed that the desulfurization reaction taking place under the electric field would be better than the traditional method.The desulfurization rate of crude oil could reach up to 77.06% at 115 ℃ at a distilled water amount of 10 m%,a desulfurizer dosage of 200 μg/g,and a demulsifier dosage of 50 μg/g.
文摘A new process for preparing poly(phenylene sulfide amide, PPSA), which is by reaction of sulfur instead of sodium sulfide as S source with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure (called sulfur solution route), is reported in the present paper. The influences of polymerization time, molar ratio of precursors, catalyst and solvent upon the polymer were investigated. To seek the best parameters of polymerization, orthogonal design was employed in the experiments. The results indicate that the molar ratio of precursors is the most significant effect on both of viscosity and yield of the polymer. The suitable parameters for preparing the related polymer are presented. The polymer was characterized by IRspectrum, 1HNMRspectrum and Raman spectrum, etc.
基金Foundation of Education Departmentof Jiangsu Government for Commercialization of High Technology Developed in Universities
文摘A new type of refuse derived fuel (RDF) for pyrolysis and gasification was prepared from municipal solid waste (MSW) in the presence of a small quantity of coal by bindless high pressure technology at room temperature. The physicochemical property of RDF was tested. Orthogonal experiment method was used to optimize the process parameters using dropping strength (mechanical strength) and thermal stability of the RDF as indices for quality of RDF. The result shows that the mixture of MSW and coal with a total moisture ranging from 5% to 17% can be easily compressed into RDF briquettes at a pressure above 70 MPa. When the briquetting pressure is higher than 100 kN and moisture content is about 10%, the qualified RDF can be obtained. The orthogonal experiment shows that the moisture can greatly affect the mechanical strength of RDF, while all the technique parameters have no obvious influence on thermal stability of RDF. The optimal parameters are a shaping pressure of 106 MPa, a moisture content of 10%, and a coal content of 20%.
