Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based ...Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education.展开更多
[Objective] The research aimed to study the application of chemical tracing experiment technique in leakage detection of hydraulic engineering.[Method] According to the current situation of Sanyuan Western Suburb Rese...[Objective] The research aimed to study the application of chemical tracing experiment technique in leakage detection of hydraulic engineering.[Method] According to the current situation of Sanyuan Western Suburb Reservoir in Xianyang City of Shaanxi Province,three sections （L1,L2 and L3） were set.KI was selected as the chemical tracer to carry out the tracing and detection research.[Result] There was no obvious leakage phenomenon in L1,L2 and L3 sections.The impermeability of rock in some dam abutments was bad.[Conclusion] The leakage reason of Western Suburb Reservoir was that the impermeability of rock in some dam abutments couldn’t satisfy seepage requirement.After the reservoir was put into operation,the water level in front of dam rose,and the ground water level of dam abutment also rose.The penetration water pressure correspondingly increased,and the water content of bank slope at the downstream of dam increased.展开更多
In order to make unexploded ordnance lose explosive ability,the chemical failure of HMX that is usually used as detonating explosive and booster was studied so as to find the corresponding chemical reagents,which can ...In order to make unexploded ordnance lose explosive ability,the chemical failure of HMX that is usually used as detonating explosive and booster was studied so as to find the corresponding chemical reagents,which can decompose HMX into compounds without explosive properties.For this purpose,several decomposition experiments between HMX and NaOH,HMX and thick H2 SO,HMX and mixed acid under different temperature conditions were carried out.According to the experimental results,it can be concluded that HMX can be decomposed by a mixture of concentrated nitric acid and concentrated nitric acid with the volume ratio of 3∶1.When its decomposed level reaches 60%,HMX will not be detonated,therefore the failure purpose is achieved.展开更多
Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studi...Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems.展开更多
By combining machine learning with the design of experiments,thereby achieving so-called active machine learning,more efficient and cheaper research can be conducted.Machine learning algorithms are more flexible and a...By combining machine learning with the design of experiments,thereby achieving so-called active machine learning,more efficient and cheaper research can be conducted.Machine learning algorithms are more flexible and are better than traditional design of experiment algorithms at investigating processes spanning all length scales of chemical engineering.While active machine learning algorithms are maturing,their applications are falling behind.In this article,three types of challenges presented by active machine learning—namely,convincing the experimental researcher,the flexibility of data creation,and the robustness of active machine learning algorithms—are identified,and ways to overcome them are discussed.A bright future lies ahead for active machine learning in chemical engineering,thanks to increasing automation and more efficient algorithms that can drive novel discoveries.展开更多
With liquid petrol gas(LPG)as carbon source,carbon felt as porous perform and hydrogen as diluent,C/C composites were fast fabricated by using a multi-physics field chemical vapor infiltration(MFCVI)process in a self-...With liquid petrol gas(LPG)as carbon source,carbon felt as porous perform and hydrogen as diluent,C/C composites were fast fabricated by using a multi-physics field chemical vapor infiltration(MFCVI)process in a self-made furnace.A set of orthogonal experiments were carried out to optimize parameters in terms of indices of density and graphitization degree.The results show the optimal indices can be achieved under the conditions of temperature 650℃,LPGconcentration 80%,gas flux 60 mL/s, total pressure 20 kPa,infiltration time 15 h.The verification experiment proves the effectiveness of the orthogonal experiments. Under the optimal conditions,the graphitization degree of 75%and bulk density of 1.69 g/cm are achieved with a uniform density distribution.At the same time,a new structure is obtained.展开更多
Wastewaters from the chemical industry are usually of high-strength and may contain minor inhibitory and recalcitrant organics that are at times not readily identifiable. This paper describes the experience of a biolo...Wastewaters from the chemical industry are usually of high-strength and may contain minor inhibitory and recalcitrant organics that are at times not readily identifiable. This paper describes the experience of a biological waste water treatment plant （WWTP） processing a COD concentration of 43000 mg·L^-1 wastewater from an oxochemical manufacturing plant. Stage improvements of the plant process by dilution of the inhibitory influent using other chemical wastewater streams resulting in a synergistic process effect, and removal of inhibitory organics by phase separation via acidification, effectively achieved process optimization producing a high quality effluent. In particular, the COD removal efficiency of granular sludge based anaerobic reactors increased from 56% to 90%. The final effluent COD decreased from 250mg·L^-1 to 50mg·L^-1, consistently meeting the COD concentration of 100 mg·L^-1 regulatory discharge limit. The success of the process enhancements supports the hypothesis that long-chain quaternary carboxylic acids act as substrate inhibitors in the biological process.展开更多
To address the serious pollution of heavy metals in AMD,the difficulty and the high cost of treatment,Fe_(3)O_(4)-L was prepared by the chemical co-precipitation method.Based on the single-factor and RSM,the effects o...To address the serious pollution of heavy metals in AMD,the difficulty and the high cost of treatment,Fe_(3)O_(4)-L was prepared by the chemical co-precipitation method.Based on the single-factor and RSM,the effects of particle size,total Fe concentration,the molar ratio of Fe^(2+)to Fe^(3+)and water bath temperature on the removal of AMD by Fe_(3)O_(4)-L prepared by chemical co-precipitation method were analyzed.Static adsorption experiments were conducted on Cu^(2+),Zn^(2+)and Pb^(2+)using Fe_(3)O_(4)-L prepared under optimal conditions as adsorbents.The adsorption properties and mechanisms were analyzed by combining SEM-EDS,XRD and FTIR for characterization.The study showed that the effects of particle size,total Fe concentration and the molar ratio of Fe^(2+)to Fe^(3+)are larger.Obtained by response surface optimization analysis,the optimum conditions for the preparation of Fe_(3)O_(4)-L were a particle size of 250 mesh,a total Fe concentration of 0.5 mol/L,and a molar ratio of Fe^(2+)to Fe^(3+)of 1:2.Under these conditions,the removal rates of Cu^(2+),Zn^(2+),and Pb^(2+)were 94.52%,88.49%,and 96.69%respectively.The adsorption of Cu^(2+),Zn^(2+)and Pb^(2+)by Fe_(3)O_(4)-L prepared under optimal conditions reached equilibrium at 180 min,with removal rates of 99.99%,85.27%,and 97.48%,respectively.The adsorption reaction of Fe_(3)O_(4)-L for Cu^(2+)and Zn^(2+)is endothermic,while that for Pb^(2+)is exothermic.Fe_(3)O_(4)-L can still maintain a high adsorption capacity after five cycles of adsorption-desorption experiments.Cu^(2+),Zn^(2+)and Pb^(2+)mainly exist as CuFe_(2)O_(4),Zn(OH)2,ZnFe_(2)O_(4)and PbS after being adsorbed by Fe_(3)O_(4)-L,which is the result of the combination of physical diffusion,ion exchange and surface complexation reaction.展开更多
By using the 2-D stratospheric-tropospheric dynamic-radiative-chemical coupled model,some sensitivity experiments have been done,which are interactions among ozone,radiation and temperature,vapor effects,as well as ef...By using the 2-D stratospheric-tropospheric dynamic-radiative-chemical coupled model,some sensitivity experiments have been done,which are interactions among ozone,radiation and temperature,vapor effects,as well as effects of source and sink.The result of temperature experiment shows that feedback interaction among ozone,radiation and temperature,mainly occurs in the upper and middle stratosphere,the maximum of ozone concentration decrease is 1 ppm,the maximum of temperature change is 6 K,and the maximum of total ozone change is 20 DU.From the experiment of water vapor,we can see that the area of the middle and high latitudes of the Northern Hemisphere is sensitive to vapor change.When the maximum difference between both surface sources is in the Antarctic,the maximum of ozone change is also there.Because the character of surface varies with latitude,dry deposition is different in different latitudes.The change of dry deposition makes ozone in boundary layer quite obvious,especially in both poles. The maximum change of total volume ozone in experiments of vapor,source and sink is more than 12 DU.展开更多
Aiming at the safety problems of toxic,flammable and explosive chemicals used in middle school chemical experiments,such as human poi-soning,skin corrosion,fire or explosion caused by improper experimental operation,a...Aiming at the safety problems of toxic,flammable and explosive chemicals used in middle school chemical experiments,such as human poi-soning,skin corrosion,fire or explosion caused by improper experimental operation,a virtual simulation method of chemical experiments based on unity is proposed.Due to the need to analyze and compare the data in chemical experiments,summarize the experimental characteristics and data relevance.Therefore,based on the Apriori algorithm,this method deeply excavates the data obtained in the chemical experiment,uses Maya to model the experimental environment,uses unity to design the interactive functions in the experimental process,and uses visual effect graph technology,shader graph technology and other methods to realize the special effect simula-tion of various chemical experiments.With this method,the virtual simula-tion prototype system of middle school chemistry experiment is developed.The example shows that this method can vividly and realistically reproduce the simulation effect of chemical experiment,find the correlation between the experimental data,classification,properties and the overall characteristics of the data,describe and predict the development trend of the data,so as to make better use of these data to provide support for chemical experiment,and not only solve the problems of poisoning,corrosion of skin and It also solves the problems that it is difficult to scientifically compare data and find data relevance in traditional chemical experiments.展开更多
Fused deposition modeling is one of the most adaptable additive production method as a result of the value-effectiveness and environment-friendly nature.However,FDM technique nevertheless possesses primary problems in...Fused deposition modeling is one of the most adaptable additive production method as a result of the value-effectiveness and environment-friendly nature.However,FDM technique nevertheless possesses primary problems in phrases of negative surface best due to including layer by using layer production method for the prototypes.It is acceptable to explore an efficient method for FDM elements to enhance the bad surface first-rate and dimensions precision.In the present research paper,an effort has been made to decorate the surface better and optimize the vital processing parameter of FDM based benchmark the use of vapor smoothing procedure(VSP).A comparative experimental take a look at has been completed by layout of experiments,Taguchi technique to analyse impact of input layout parameters at the floor finish of benchmark FDM parts.The outcomes of prevailing research display that VSP treatment improves the surface excellent of FDM components to micro stage with negligible dimensional variation.It is observed that improved floor excellent is observed in the 1,2,-Dichloroethane chemical at 90°component construct orientation,0.25 mm layer thickness,10%fill density and 90 sec Exposure times.展开更多
At present,most experimental teaching systems lack guidance of an operator,and thus users often do not know what to do during an experiment.The user load is therefore increased,and the learning efficiency of the stude...At present,most experimental teaching systems lack guidance of an operator,and thus users often do not know what to do during an experiment.The user load is therefore increased,and the learning efficiency of the students is decreased.To solve the problem of insufficient system interactivity and guidance,an experimental navigation system based on multi-mode fusion is proposed in this paper.The system first obtains user information by sensing the hardware devices,intelligently perceives the user intention and progress of the experiment according to the information acquired,and finally carries out a multi-modal intelligent navigation process for users.As an innovative aspect of this study,an intelligent multi-mode navigation system is used to guide users in conducting experiments,thereby reducing the user load and enabling the users to effectively complete their experiments.The results prove that this system can guide users in completing their experiments,and can effectively reduce the user load during the interaction process and improve the efficiency.展开更多
基金National Innovation and Entrepreneurship Program for College Students(202218213001)Science and Technology Innovation Strategy of Guangdong Province(Science and Technology Innovation Cultivation of University Students 2020329182130C000002).
文摘Background Most existing chemical experiment teaching systems lack solid immersive experiences,making it difficult to engage students.To address these challenges,we propose a chemical simulation teaching system based on virtual reality and gesture interaction.Methods The parameters of the models were obtained through actual investigation,whereby Blender and 3DS MAX were used to model and import these parameters into a physics engine.By establishing an interface for the physics engine,gesture interaction hardware,and virtual reality(VR)helmet,a highly realistic chemical experiment environment was created.Using code script logic,particle systems,as well as other systems,chemical phenomena were simulated.Furthermore,we created an online teaching platform using streaming media and databases to address the problems of distance teaching.Results The proposed system was evaluated against two mainstream products in the market.In the experiments,the proposed system outperformed the other products in terms of fidelity and practicality.Conclusions The proposed system which offers realistic simulations and practicability,can help improve the high school chemistry experimental education.
文摘[Objective] The research aimed to study the application of chemical tracing experiment technique in leakage detection of hydraulic engineering.[Method] According to the current situation of Sanyuan Western Suburb Reservoir in Xianyang City of Shaanxi Province,three sections （L1,L2 and L3） were set.KI was selected as the chemical tracer to carry out the tracing and detection research.[Result] There was no obvious leakage phenomenon in L1,L2 and L3 sections.The impermeability of rock in some dam abutments was bad.[Conclusion] The leakage reason of Western Suburb Reservoir was that the impermeability of rock in some dam abutments couldn’t satisfy seepage requirement.After the reservoir was put into operation,the water level in front of dam rose,and the ground water level of dam abutment also rose.The penetration water pressure correspondingly increased,and the water content of bank slope at the downstream of dam increased.
文摘In order to make unexploded ordnance lose explosive ability,the chemical failure of HMX that is usually used as detonating explosive and booster was studied so as to find the corresponding chemical reagents,which can decompose HMX into compounds without explosive properties.For this purpose,several decomposition experiments between HMX and NaOH,HMX and thick H2 SO,HMX and mixed acid under different temperature conditions were carried out.According to the experimental results,it can be concluded that HMX can be decomposed by a mixture of concentrated nitric acid and concentrated nitric acid with the volume ratio of 3∶1.When its decomposed level reaches 60%,HMX will not be detonated,therefore the failure purpose is achieved.
文摘Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems.
基金financial support from the Fund for Scientific Research Flanders(FWO Flanders)through the doctoral fellowship grants(1185822N,1S45522N,and 3F018119)funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme(818607)。
文摘By combining machine learning with the design of experiments,thereby achieving so-called active machine learning,more efficient and cheaper research can be conducted.Machine learning algorithms are more flexible and are better than traditional design of experiment algorithms at investigating processes spanning all length scales of chemical engineering.While active machine learning algorithms are maturing,their applications are falling behind.In this article,three types of challenges presented by active machine learning—namely,convincing the experimental researcher,the flexibility of data creation,and the robustness of active machine learning algorithms—are identified,and ways to overcome them are discussed.A bright future lies ahead for active machine learning in chemical engineering,thanks to increasing automation and more efficient algorithms that can drive novel discoveries.
基金Projects(5080211550721003)supported by the National Natural Science Foundation of ChinaProject(2006CB600901)supported by the National Basic Research Program of China
文摘With liquid petrol gas(LPG)as carbon source,carbon felt as porous perform and hydrogen as diluent,C/C composites were fast fabricated by using a multi-physics field chemical vapor infiltration(MFCVI)process in a self-made furnace.A set of orthogonal experiments were carried out to optimize parameters in terms of indices of density and graphitization degree.The results show the optimal indices can be achieved under the conditions of temperature 650℃,LPGconcentration 80%,gas flux 60 mL/s, total pressure 20 kPa,infiltration time 15 h.The verification experiment proves the effectiveness of the orthogonal experiments. Under the optimal conditions,the graphitization degree of 75%and bulk density of 1.69 g/cm are achieved with a uniform density distribution.At the same time,a new structure is obtained.
文摘Wastewaters from the chemical industry are usually of high-strength and may contain minor inhibitory and recalcitrant organics that are at times not readily identifiable. This paper describes the experience of a biological waste water treatment plant （WWTP） processing a COD concentration of 43000 mg·L^-1 wastewater from an oxochemical manufacturing plant. Stage improvements of the plant process by dilution of the inhibitory influent using other chemical wastewater streams resulting in a synergistic process effect, and removal of inhibitory organics by phase separation via acidification, effectively achieved process optimization producing a high quality effluent. In particular, the COD removal efficiency of granular sludge based anaerobic reactors increased from 56% to 90%. The final effluent COD decreased from 250mg·L^-1 to 50mg·L^-1, consistently meeting the COD concentration of 100 mg·L^-1 regulatory discharge limit. The success of the process enhancements supports the hypothesis that long-chain quaternary carboxylic acids act as substrate inhibitors in the biological process.
基金This work was supported by the National Natural Science Foundation of China(41672247)Liaoning Province’s“Program for Promoting Liaoning Talents”(XLYC1807159)+1 种基金the Discipline Innovation Team of Liaoning Technical University(LNTU20TD-21)the Liaoning Provincial Department of Education(LJKZ0324).
文摘To address the serious pollution of heavy metals in AMD,the difficulty and the high cost of treatment,Fe_(3)O_(4)-L was prepared by the chemical co-precipitation method.Based on the single-factor and RSM,the effects of particle size,total Fe concentration,the molar ratio of Fe^(2+)to Fe^(3+)and water bath temperature on the removal of AMD by Fe_(3)O_(4)-L prepared by chemical co-precipitation method were analyzed.Static adsorption experiments were conducted on Cu^(2+),Zn^(2+)and Pb^(2+)using Fe_(3)O_(4)-L prepared under optimal conditions as adsorbents.The adsorption properties and mechanisms were analyzed by combining SEM-EDS,XRD and FTIR for characterization.The study showed that the effects of particle size,total Fe concentration and the molar ratio of Fe^(2+)to Fe^(3+)are larger.Obtained by response surface optimization analysis,the optimum conditions for the preparation of Fe_(3)O_(4)-L were a particle size of 250 mesh,a total Fe concentration of 0.5 mol/L,and a molar ratio of Fe^(2+)to Fe^(3+)of 1:2.Under these conditions,the removal rates of Cu^(2+),Zn^(2+),and Pb^(2+)were 94.52%,88.49%,and 96.69%respectively.The adsorption of Cu^(2+),Zn^(2+)and Pb^(2+)by Fe_(3)O_(4)-L prepared under optimal conditions reached equilibrium at 180 min,with removal rates of 99.99%,85.27%,and 97.48%,respectively.The adsorption reaction of Fe_(3)O_(4)-L for Cu^(2+)and Zn^(2+)is endothermic,while that for Pb^(2+)is exothermic.Fe_(3)O_(4)-L can still maintain a high adsorption capacity after five cycles of adsorption-desorption experiments.Cu^(2+),Zn^(2+)and Pb^(2+)mainly exist as CuFe_(2)O_(4),Zn(OH)2,ZnFe_(2)O_(4)and PbS after being adsorbed by Fe_(3)O_(4)-L,which is the result of the combination of physical diffusion,ion exchange and surface complexation reaction.
文摘By using the 2-D stratospheric-tropospheric dynamic-radiative-chemical coupled model,some sensitivity experiments have been done,which are interactions among ozone,radiation and temperature,vapor effects,as well as effects of source and sink.The result of temperature experiment shows that feedback interaction among ozone,radiation and temperature,mainly occurs in the upper and middle stratosphere,the maximum of ozone concentration decrease is 1 ppm,the maximum of temperature change is 6 K,and the maximum of total ozone change is 20 DU.From the experiment of water vapor,we can see that the area of the middle and high latitudes of the Northern Hemisphere is sensitive to vapor change.When the maximum difference between both surface sources is in the Antarctic,the maximum of ozone change is also there.Because the character of surface varies with latitude,dry deposition is different in different latitudes.The change of dry deposition makes ozone in boundary layer quite obvious,especially in both poles. The maximum change of total volume ozone in experiments of vapor,source and sink is more than 12 DU.
文摘Aiming at the safety problems of toxic,flammable and explosive chemicals used in middle school chemical experiments,such as human poi-soning,skin corrosion,fire or explosion caused by improper experimental operation,a virtual simulation method of chemical experiments based on unity is proposed.Due to the need to analyze and compare the data in chemical experiments,summarize the experimental characteristics and data relevance.Therefore,based on the Apriori algorithm,this method deeply excavates the data obtained in the chemical experiment,uses Maya to model the experimental environment,uses unity to design the interactive functions in the experimental process,and uses visual effect graph technology,shader graph technology and other methods to realize the special effect simula-tion of various chemical experiments.With this method,the virtual simula-tion prototype system of middle school chemistry experiment is developed.The example shows that this method can vividly and realistically reproduce the simulation effect of chemical experiment,find the correlation between the experimental data,classification,properties and the overall characteristics of the data,describe and predict the development trend of the data,so as to make better use of these data to provide support for chemical experiment,and not only solve the problems of poisoning,corrosion of skin and It also solves the problems that it is difficult to scientifically compare data and find data relevance in traditional chemical experiments.
基金The authors would like to thank the CIPET:IPT Ahmedabad for the grant to provide a facility in which to carry out this study.
文摘Fused deposition modeling is one of the most adaptable additive production method as a result of the value-effectiveness and environment-friendly nature.However,FDM technique nevertheless possesses primary problems in phrases of negative surface best due to including layer by using layer production method for the prototypes.It is acceptable to explore an efficient method for FDM elements to enhance the bad surface first-rate and dimensions precision.In the present research paper,an effort has been made to decorate the surface better and optimize the vital processing parameter of FDM based benchmark the use of vapor smoothing procedure(VSP).A comparative experimental take a look at has been completed by layout of experiments,Taguchi technique to analyse impact of input layout parameters at the floor finish of benchmark FDM parts.The outcomes of prevailing research display that VSP treatment improves the surface excellent of FDM components to micro stage with negligible dimensional variation.It is observed that improved floor excellent is observed in the 1,2,-Dichloroethane chemical at 90°component construct orientation,0.25 mm layer thickness,10%fill density and 90 sec Exposure times.
基金the the National Key R&D Program of China(No.2018YFB1004901)the Independent Innovation Team Project of Jinan City(No.2019GXRC013).
文摘At present,most experimental teaching systems lack guidance of an operator,and thus users often do not know what to do during an experiment.The user load is therefore increased,and the learning efficiency of the students is decreased.To solve the problem of insufficient system interactivity and guidance,an experimental navigation system based on multi-mode fusion is proposed in this paper.The system first obtains user information by sensing the hardware devices,intelligently perceives the user intention and progress of the experiment according to the information acquired,and finally carries out a multi-modal intelligent navigation process for users.As an innovative aspect of this study,an intelligent multi-mode navigation system is used to guide users in conducting experiments,thereby reducing the user load and enabling the users to effectively complete their experiments.The results prove that this system can guide users in completing their experiments,and can effectively reduce the user load during the interaction process and improve the efficiency.
