[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis...[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis×E.urophylla were studied. [Result] There was certain difference in leaf characteristics values between the 2 species. The leaf areas of E. urophylla and E. grandis×E.urophylla both had significant correlation with leaf length,leaf width,leaf perimeter,leaf length × leaf width,the ratio of leaf length to leaf width,shape factor,etc.,so the factors could be constructed into a regression model with leaf area. Among them,the best 2 models for leaf area calculation which were built by leaf length × leaf width of E. urophylla and E. grandis×E.urophylla both had relatively high accuracy and practical applications. [Conclusion] The research provides a simple and effective leaf area measurement method for studies on the 2 tree species.展开更多
Based on the hexagonal crystallite model of graphite,the electrochemical characteristics of carbon atoms on the edge and basal plane were proposed by analyzing graphite crystal structure and bonds of carbon atoms in d...Based on the hexagonal crystallite model of graphite,the electrochemical characteristics of carbon atoms on the edge and basal plane were proposed by analyzing graphite crystal structure and bonds of carbon atoms in different sites.A spherical close-packed model for graphite particle was developed.The fractions of surface carbon atoms(SCA) and edge carbon atoms(ECA) were derived in the expression of crystallographic parameters and particle size,and the effects of ECA on the initial irreversible capacity and the mechanisms of action were analyzed and verified.The results show that the atoms on the edge are more active for electrochemical reactions,such as electrolyte decomposition and tendency to form stable bond with other atoms and groups.For the practical graphite particle,corresponding modifying factors were introduced to revise the difference in calculating results.The revised expression is suitable for the calculation of the fractions of SCA and ECA for carbon materials such as graphite,disordered carbon and modified graphite.展开更多
In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distanc...In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distance of wetting fronts are still unclear.Besides,wetting front migration distance and leaching time are usually required to optimize the leaching process.In this study,wetting front migration tests of ionadsorption rare earth ores during the multi-hole fluid injection(the spacing between injection holes was 10 cm,12 cm and 14 cm)and single-hole fluid injection were completed under the constant water head height.At the pre-intersection stage,the wetting front migration laws of ion-adsorption rare earth ores during the multi-hole fluid injection and single-hole fluid injection were identical.At the postintersection stage,the intersection accelerated the wetting front migration.By using the Darcy’s law,the intersection effect of wetting fronts during the multi-hole liquid injection was transformed into the water head height directly above the intersection.Finally,based on the Green-Ampt model,a wetting front migration model of ion-adsorption rare earth ores during the multi-hole unsaturated liquid injection was established.Error analysis results showed that the proposed model can accurately simulate the infiltration process under experimental conditions.The research results enrich the infiltration law and theory of ion-adsorption rare earth ores during the multi-hole liquid injection,and this study provides a scientific basis for optimizing the liquid injection well pattern parameters of ion-adsorption rare earth in situ leaching in the future.展开更多
A bridge project is taken as an example to analyze the application of bearing capacity detection and evaluation.This article provides a basic overview of the project,the application of bearing capacity detection techn...A bridge project is taken as an example to analyze the application of bearing capacity detection and evaluation.This article provides a basic overview of the project,the application of bearing capacity detection technology,and the bearing capacity assessment analysis.It is hoped that this analysis can provide a scientific reference for the load-bearing capacity detection and evaluation work in bridge engineering projects,thereby achieving a scientific assessment of the overall load-bearing capacity of the bridge engineering structure.展开更多
By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture t...By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice.展开更多
A calculation method for predicting the formation of alkali-silica gel and analyzing the relationship of ASR induced expansion and aggregate size was proposed. The complicated chemistry of alkali silica reaction was s...A calculation method for predicting the formation of alkali-silica gel and analyzing the relationship of ASR induced expansion and aggregate size was proposed. The complicated chemistry of alkali silica reaction was simplified to be controlled by the diffusion process of chemical ions into reactive aggregates. The transport of chemical ions was described by the Fick's law. The ASR induced expansion was assumed to be directly related to the volume of produced alkali-silica gel. The finally expansion of a representative volume element (RVE) of concrete was then calculated according to the ratio of volume of alkali-silica gel and RVE. The input parameters of the model contains radius of reactive aggregate, volume fraction of reactive aggregate, initial concentration of chemical ions and porosity of cement paste. The applicability of the model was validated by an experiment of ASR-affected concrete specimens containing glass aggregate. It is shown that the amount of alkali-silica gel and ASR induced expansion can be well predicted. The expansion increasing with the decreasing aggregate size can be reproduced by the proposed model.展开更多
On the basis of analysis and selection of factors influencing operation cost of coal resources development, fuzzy set method and artificial neural network (ANN) were adopted to set up the classification analysis model...On the basis of analysis and selection of factors influencing operation cost of coal resources development, fuzzy set method and artificial neural network (ANN) were adopted to set up the classification analysis model of coal resources. The collected samples were classified by using this model. Meanwhile, the pattern recognition model for classifying of the coal resources was built according to the factors influencing operation cost. Based on the results achieved above, in the light of the theory of information diffusion, the calculation model for operation cost of coal resources development has been presented and applied in practice, showing that these models are reasonable.展开更多
The process and path of retrometamorphism of coesite have great significance to our understanding of the P-T tracks of the exhumation of ultrahigh-pressure metamorphic rocks. Most of the coesites in the eclogite from ...The process and path of retrometamorphism of coesite have great significance to our understanding of the P-T tracks of the exhumation of ultrahigh-pressure metamorphic rocks. Most of the coesites in the eclogite from Shima, Anhui Province, the Dabie Mountains, China, are found degraded to quartz partly or wholly, with ruptures occurring in the shells, outside which include the coesite and quartz. According to the microscopic observation, the sample of coesite inclusion is composed of garnet, quartz and coesite, based on which we have built a three-shelled composite sphere model to compute the transition of coesite. Based on the crystal growth formulas and pressure conditions of the ruptures in the garnet, we have calculated the radius of the quartz sphere, which depends on temperature, and eventually drawn the different retrometamorphic paths for different retrometamorphism rates.展开更多
A simulation calculation model for the solubility of insoluble compound MmAa in complex system was established.According to coordination equilibrium principle,relevant dissociation reaction,complexation reaction,self-...A simulation calculation model for the solubility of insoluble compound MmAa in complex system was established.According to coordination equilibrium principle,relevant dissociation reaction,complexation reaction,self-complexation reaction and protonation reaction during insoluble compound dissolving were considered and then the mass balance equations about solubility calculation were obtained.In the case analysis,the solubility of silver chloride in ammonia system was obtained by simulation calculation,and curved surface charts of thermodynamic equilibrium about the total concentration of silver ions,pH and concentration of ammonia ions were drawn correspondingly.The results show that under the conditions of room temperature and 6 mol/L ammonia concentration,the calculated solubility value of silver chloride(34 g/L) is close to the actual value(31 g/L),demonstrating that this model is suitable for solubility calculation of insoluble compound MmAa in the complex system.展开更多
Two calculation models of mass action concentrations for CaO-MgO-SiO_2-Al_2O_3-Cr_2O_3 penta-slag was presented whether 3CaO·Cr_2O_3·3SiO_2 was existence or not.Equilibrium mass action concentration of each ...Two calculation models of mass action concentrations for CaO-MgO-SiO_2-Al_2O_3-Cr_2O_3 penta-slag was presented whether 3CaO·Cr_2O_3·3SiO_2 was existence or not.Equilibrium mass action concentration of each element structure was gained.And the models results were compared with experimental activity.The final results illustrated the model without 3CaO·Cr_2O_33SiO_2 was suit for reality.The model could response the element structure of slag as well.展开更多
In order to calculate the air temperature of the near surface layer in urban environment,the surface layer air was divided into several sections in the vertical direction,and some energy balance equations were develop...In order to calculate the air temperature of the near surface layer in urban environment,the surface layer air was divided into several sections in the vertical direction,and some energy balance equations were developed for each air layer,in which the heat exchange due to vertical turbulence and horizontal air flow was taken into account.Then,the vertical temperature distribution of the surface layer air was obtained through the coupled calculation using the energy balance equations of underlying surfaces and building walls.Moreover,the measured air temperatures in a small area(with a horizontal scale of less than 500 m) and a large area(with a horizontal scale of more than 1 000 m) in Guangzhou in summer were used to validate the proposed model.The calculated results accord well with the measured ones,with a maximum relative error of 4.18%.It is thus concluded that the proposed model is a high-accuracy method to theoretically analyze the urban heat island and the thermal environment.展开更多
The application of PV facades emerges greatly in recent years and however its calculation methods and analysis remains insufficient under the weather conditions of China. In such demand, this paper investigates PV fac...The application of PV facades emerges greatly in recent years and however its calculation methods and analysis remains insufficient under the weather conditions of China. In such demand, this paper investigates PV facade in terms of PV electricity generation in different arrangements and weather conditions of four major cities in China. The calculation models for PV facade are developed and validated by comparing the results with the measured data from the field experiments. A parametric study is carried out to provide a reference for the optimal design of the PV facades. The results show that with various cities, building orientations, building forms, materials and arrangements of PV modules, there is a distinct difference in the electrical output energy of PV facades. Weather conditions nlav a very important role in terms of PV generation nerformance of PV facades.展开更多
The nonwoven composites have sandwich structure, with the first and third layers being nonwovens and the middle layer of woven fabric. On the basis of tests of the single rip tearing strength and drawing out resistanc...The nonwoven composites have sandwich structure, with the first and third layers being nonwovens and the middle layer of woven fabric. On the basis of tests of the single rip tearing strength and drawing out resistances of both the nonwoven composites and the woven fabric, the single rip tearing failure mechanism of the composites were analyzed. Then theoretical calculation model for the single rip tearing strength was established, which indicates that the breaking strength of warp and weft yams in the nonwoven composites, the density of warp and weft yarns and drawing out resistances are the main influencing factors. In the end, experimental verification was made, which shows that theoretical values conform to the measured values well.展开更多
This paper discussed the importance of the delayed neutron detection system.We improved the delayed neutron detection station and delayed neutron detector,so the noise was greatly decreased and the detection efficienc...This paper discussed the importance of the delayed neutron detection system.We improved the delayed neutron detection station and delayed neutron detector,so the noise was greatly decreased and the detection efficiency was greatly increased.After the improvement the stability of the detector was enhanced and the false alarm was eliminated.We introduced the principle of the gas lift pump designed for the sodium cooled fast reactor.A calculation model of the failed fuel detection system of CEFR was proposed,and from the model a code using LabWindows/CVI was developed.The minimum broken area that could be detected by the delayed neutron detection system of CEFR was calculated and the delayed neutron detection signal in a few representative transient conditions during fuel failure happened was stimulated.展开更多
This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 ...This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 binary oxides. and found good agreemenl between estimated and experimental entropies.展开更多
High-speed motor has the characteristics of high frequency, high temperature, and more stress, resulting in the field distribution inside the motor being complicated. To better study the electromagnetic characteristic...High-speed motor has the characteristics of high frequency, high temperature, and more stress, resulting in the field distribution inside the motor being complicated. To better study the electromagnetic characteristics of silicon steel sheet for high-speed motor. In this article, a study on the calculation model of silicon sheet electromagnetic characteristics considers the effects of electromagnetic, stress, and temperature factors. The study is divided into two parts, one is to propose the calculation model of silicon steel sheet’s permeability;the other is to improve the calculation model of silicon steel sheet’s loss. Then, the magnetic field, stress field, and temperature field of a surface mount high speed permanent magnet motor(SMHSPMSM) are analyzed by finite element method(FEM), and the results under the consideration of magnetic, stress, and temperature factors are brought into the calculation model for calculation. Finally, the accuracy of the calculation model for electromagnetic characteristics of silicon steel sheet is verified by comparing the calculated results with the finite element results.展开更多
Cobalt-protein complexes play an important role in biochemical processes.The structure of the model molecule,Co(H_2O)_3SO_4(phen) has been studied by molecular mechanics.The molecular force field (MM2) parameters have...Cobalt-protein complexes play an important role in biochemical processes.The structure of the model molecule,Co(H_2O)_3SO_4(phen) has been studied by molecular mechanics.The molecular force field (MM2) parameters have been developed for the particular class of the complexes.展开更多
This paper describes the numerical calculations of gaseous reaction flows in a model of gas turbine combustors. The profiles of hydrodynamic and thermodynamic patterns in a three-dimensional combustor model are obtain...This paper describes the numerical calculations of gaseous reaction flows in a model of gas turbine combustors. The profiles of hydrodynamic and thermodynamic patterns in a three-dimensional combustor model are obtained by solving the governing differential transport equations. The well-established numerical prediction algorithm SIMPLE, the modified k-ε turbulence model and k-ε-g turbulent diffusion flame model have been adopted in computations. The β function has been selected as probability density function. The effect of combustion process on flow patterns has been investigated. The calculated results have been verified by experiments. They are in remarkably good agreement.展开更多
In response to the lack of global quantitative research on the potential and scale prediction of CO_(2) capture,utilization and storage(CCUS)in China under the background of carbon peak and carbon neutrality goals,thi...In response to the lack of global quantitative research on the potential and scale prediction of CO_(2) capture,utilization and storage(CCUS)in China under the background of carbon peak and carbon neutrality goals,this study predicts the future economic costs of different links of ccUS technologies and the carbon capture needs of different industries in the scenario of fossil energy continuation.Based on the CO_(2) utilization and storage potential and spatial distribution in China,a cost-scale calculation model for different regions in China in 206o is constructed to predict the whole-process economic cost and its corresponding scale potential of CCUs.The results show that a local+remote storage mode is preferred,together with a local utilization mode,to meet China's 27×10^(8)t/a CO_(2) emission reduction demand under the scenario of fossil energy continuation.Specifically,about 5×10^(8) t CO_(2) emission is reduced by capture utilization,and the whole-process cost is about-1400-200 RMB/t;about 22×10^(8) t CO_(2) emission is reduced by capture storage,and the whole-process cost is about 200-450 RMB/t.According to the model results,it is recommended to develop the chemical utilization industry based on P2X(Power to X,where X is raw material)technology,construct the CcUs industrial cluster,and explore a multi-party win-win cooperation mode.A scheme of national trunk pipeline network connecting areas connecting intensive emission reduction demand areas and target storage areas is suggested.The emission reduction cost of thermal power based on CCUS is calculated to be 0.16 RMB/(kW.h).展开更多
The use of open-type check dams in mountainous areas has become common practice in order to mitigate the effects of debris flow and extend the service life of engineering structures.The beam dam,a common debris flow c...The use of open-type check dams in mountainous areas has become common practice in order to mitigate the effects of debris flow and extend the service life of engineering structures.The beam dam,a common debris flow control system,has received less attention in research on the impact process of debris flow and check dams compared to solid check dams.Additionally,the estimation of impact pressure in debris flow primarily considers debris flow characteristics,without taking into account the influence of geometric characteristics of the transmission structure.To better understand the impact process of debris flow on beam dams,a series of small-scale debris flow impact tests were conducted in a model flume.Key parameters,including velocity,depth,and impact pressure,were measured.The results show that the maximum impact pressure of debris flow is affected by both the characteristics of the debris flow and the relative opening size of the beam dam.Due to flow and edge occlusion in the middle of the beam dam,the discharge of debris flow is enhanced,resulting in a longer impact process and higher maximum impact pressure.Based on these findings,a calculation model of the maximum impact pressure of debris flow at the midpoint of the middle beam is proposed,which can be used to estimate the impact of debris flow on the discharge part of the beam dam.展开更多
基金Supported by Key Science and Technology Project of Forestry in Guangxi Province for the Eleventh Five-year Plan ([2009] No.8)~~
文摘[Objective] The aim was to build an optimal leaf area measurement model of E. urophylla and E. grandis×E.urophylla. [Method] The correlation between leaf area and leaf's eigenvalue of E. urophylla and E. grandis×E.urophylla were studied. [Result] There was certain difference in leaf characteristics values between the 2 species. The leaf areas of E. urophylla and E. grandis×E.urophylla both had significant correlation with leaf length,leaf width,leaf perimeter,leaf length × leaf width,the ratio of leaf length to leaf width,shape factor,etc.,so the factors could be constructed into a regression model with leaf area. Among them,the best 2 models for leaf area calculation which were built by leaf length × leaf width of E. urophylla and E. grandis×E.urophylla both had relatively high accuracy and practical applications. [Conclusion] The research provides a simple and effective leaf area measurement method for studies on the 2 tree species.
基金Project (09001232) supported by the Doctoral Foundation of Henan University of Science and Technology,China
文摘Based on the hexagonal crystallite model of graphite,the electrochemical characteristics of carbon atoms on the edge and basal plane were proposed by analyzing graphite crystal structure and bonds of carbon atoms in different sites.A spherical close-packed model for graphite particle was developed.The fractions of surface carbon atoms(SCA) and edge carbon atoms(ECA) were derived in the expression of crystallographic parameters and particle size,and the effects of ECA on the initial irreversible capacity and the mechanisms of action were analyzed and verified.The results show that the atoms on the edge are more active for electrochemical reactions,such as electrolyte decomposition and tendency to form stable bond with other atoms and groups.For the practical graphite particle,corresponding modifying factors were introduced to revise the difference in calculating results.The revised expression is suitable for the calculation of the fractions of SCA and ECA for carbon materials such as graphite,disordered carbon and modified graphite.
基金This research was funded by the National Natural Science Foundation of China(Grant No.52174113)the Young Jinggang Scholars Award Program in Jiangxi Province,China(Grant No.QNJG2018051)the“Thousand Talents”of Jiangxi Province,China(Grant No.jxsq2019201043).
文摘In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distance of wetting fronts are still unclear.Besides,wetting front migration distance and leaching time are usually required to optimize the leaching process.In this study,wetting front migration tests of ionadsorption rare earth ores during the multi-hole fluid injection(the spacing between injection holes was 10 cm,12 cm and 14 cm)and single-hole fluid injection were completed under the constant water head height.At the pre-intersection stage,the wetting front migration laws of ion-adsorption rare earth ores during the multi-hole fluid injection and single-hole fluid injection were identical.At the postintersection stage,the intersection accelerated the wetting front migration.By using the Darcy’s law,the intersection effect of wetting fronts during the multi-hole liquid injection was transformed into the water head height directly above the intersection.Finally,based on the Green-Ampt model,a wetting front migration model of ion-adsorption rare earth ores during the multi-hole unsaturated liquid injection was established.Error analysis results showed that the proposed model can accurately simulate the infiltration process under experimental conditions.The research results enrich the infiltration law and theory of ion-adsorption rare earth ores during the multi-hole liquid injection,and this study provides a scientific basis for optimizing the liquid injection well pattern parameters of ion-adsorption rare earth in situ leaching in the future.
文摘A bridge project is taken as an example to analyze the application of bearing capacity detection and evaluation.This article provides a basic overview of the project,the application of bearing capacity detection technology,and the bearing capacity assessment analysis.It is hoped that this analysis can provide a scientific reference for the load-bearing capacity detection and evaluation work in bridge engineering projects,thereby achieving a scientific assessment of the overall load-bearing capacity of the bridge engineering structure.
文摘By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice.
基金Funded by the Major state Basic Research Development Program of China (973 Program) (No. 2009CB623203)
文摘A calculation method for predicting the formation of alkali-silica gel and analyzing the relationship of ASR induced expansion and aggregate size was proposed. The complicated chemistry of alkali silica reaction was simplified to be controlled by the diffusion process of chemical ions into reactive aggregates. The transport of chemical ions was described by the Fick's law. The ASR induced expansion was assumed to be directly related to the volume of produced alkali-silica gel. The finally expansion of a representative volume element (RVE) of concrete was then calculated according to the ratio of volume of alkali-silica gel and RVE. The input parameters of the model contains radius of reactive aggregate, volume fraction of reactive aggregate, initial concentration of chemical ions and porosity of cement paste. The applicability of the model was validated by an experiment of ASR-affected concrete specimens containing glass aggregate. It is shown that the amount of alkali-silica gel and ASR induced expansion can be well predicted. The expansion increasing with the decreasing aggregate size can be reproduced by the proposed model.
文摘On the basis of analysis and selection of factors influencing operation cost of coal resources development, fuzzy set method and artificial neural network (ANN) were adopted to set up the classification analysis model of coal resources. The collected samples were classified by using this model. Meanwhile, the pattern recognition model for classifying of the coal resources was built according to the factors influencing operation cost. Based on the results achieved above, in the light of the theory of information diffusion, the calculation model for operation cost of coal resources development has been presented and applied in practice, showing that these models are reasonable.
基金the National Natural Science Foundation of China grants 40172019 ,40272083 the Natural Science Foundation of HubeiProvince grant 2002AB020.
文摘The process and path of retrometamorphism of coesite have great significance to our understanding of the P-T tracks of the exhumation of ultrahigh-pressure metamorphic rocks. Most of the coesites in the eclogite from Shima, Anhui Province, the Dabie Mountains, China, are found degraded to quartz partly or wholly, with ruptures occurring in the shells, outside which include the coesite and quartz. According to the microscopic observation, the sample of coesite inclusion is composed of garnet, quartz and coesite, based on which we have built a three-shelled composite sphere model to compute the transition of coesite. Based on the crystal growth formulas and pressure conditions of the ruptures in the garnet, we have calculated the radius of the quartz sphere, which depends on temperature, and eventually drawn the different retrometamorphic paths for different retrometamorphism rates.
基金Project(2007CB613604) supported by the National Basic Research Program of China
文摘A simulation calculation model for the solubility of insoluble compound MmAa in complex system was established.According to coordination equilibrium principle,relevant dissociation reaction,complexation reaction,self-complexation reaction and protonation reaction during insoluble compound dissolving were considered and then the mass balance equations about solubility calculation were obtained.In the case analysis,the solubility of silver chloride in ammonia system was obtained by simulation calculation,and curved surface charts of thermodynamic equilibrium about the total concentration of silver ions,pH and concentration of ammonia ions were drawn correspondingly.The results show that under the conditions of room temperature and 6 mol/L ammonia concentration,the calculated solubility value of silver chloride(34 g/L) is close to the actual value(31 g/L),demonstrating that this model is suitable for solubility calculation of insoluble compound MmAa in the complex system.
文摘Two calculation models of mass action concentrations for CaO-MgO-SiO_2-Al_2O_3-Cr_2O_3 penta-slag was presented whether 3CaO·Cr_2O_3·3SiO_2 was existence or not.Equilibrium mass action concentration of each element structure was gained.And the models results were compared with experimental activity.The final results illustrated the model without 3CaO·Cr_2O_33SiO_2 was suit for reality.The model could response the element structure of slag as well.
基金Project(50808083) supported by the National Natural Science Foundation of China
文摘In order to calculate the air temperature of the near surface layer in urban environment,the surface layer air was divided into several sections in the vertical direction,and some energy balance equations were developed for each air layer,in which the heat exchange due to vertical turbulence and horizontal air flow was taken into account.Then,the vertical temperature distribution of the surface layer air was obtained through the coupled calculation using the energy balance equations of underlying surfaces and building walls.Moreover,the measured air temperatures in a small area(with a horizontal scale of less than 500 m) and a large area(with a horizontal scale of more than 1 000 m) in Guangzhou in summer were used to validate the proposed model.The calculated results accord well with the measured ones,with a maximum relative error of 4.18%.It is thus concluded that the proposed model is a high-accuracy method to theoretically analyze the urban heat island and the thermal environment.
基金Sponsored by the National Natural Science Foundation of China (Grant No.51008136)the Graduates’ Innovation and Enterprise Fund of HUST (Grant No.HF-11-12-2013)
文摘The application of PV facades emerges greatly in recent years and however its calculation methods and analysis remains insufficient under the weather conditions of China. In such demand, this paper investigates PV facade in terms of PV electricity generation in different arrangements and weather conditions of four major cities in China. The calculation models for PV facade are developed and validated by comparing the results with the measured data from the field experiments. A parametric study is carried out to provide a reference for the optimal design of the PV facades. The results show that with various cities, building orientations, building forms, materials and arrangements of PV modules, there is a distinct difference in the electrical output energy of PV facades. Weather conditions nlav a very important role in terms of PV generation nerformance of PV facades.
文摘The nonwoven composites have sandwich structure, with the first and third layers being nonwovens and the middle layer of woven fabric. On the basis of tests of the single rip tearing strength and drawing out resistances of both the nonwoven composites and the woven fabric, the single rip tearing failure mechanism of the composites were analyzed. Then theoretical calculation model for the single rip tearing strength was established, which indicates that the breaking strength of warp and weft yams in the nonwoven composites, the density of warp and weft yarns and drawing out resistances are the main influencing factors. In the end, experimental verification was made, which shows that theoretical values conform to the measured values well.
文摘This paper discussed the importance of the delayed neutron detection system.We improved the delayed neutron detection station and delayed neutron detector,so the noise was greatly decreased and the detection efficiency was greatly increased.After the improvement the stability of the detector was enhanced and the false alarm was eliminated.We introduced the principle of the gas lift pump designed for the sodium cooled fast reactor.A calculation model of the failed fuel detection system of CEFR was proposed,and from the model a code using LabWindows/CVI was developed.The minimum broken area that could be detected by the delayed neutron detection system of CEFR was calculated and the delayed neutron detection signal in a few representative transient conditions during fuel failure happened was stimulated.
文摘This paper establishes a new model for calculation of the standard entropies of solid binary oxides as follows: S_(29)=27.07×Φ_1+1.120×Φ_2+n_1×k×Φ, -22.19 e.u (R=0.9960) We have invesigated 103 binary oxides. and found good agreemenl between estimated and experimental entropies.
基金the Key International Cooperation of National Natural Science Foundation of China under Grant 51920105011Liaoning BaiQianWan Talents Programthe Natural Science Foundation of LiaoNing Province under Grant 2021-YQ-09。
文摘High-speed motor has the characteristics of high frequency, high temperature, and more stress, resulting in the field distribution inside the motor being complicated. To better study the electromagnetic characteristics of silicon steel sheet for high-speed motor. In this article, a study on the calculation model of silicon sheet electromagnetic characteristics considers the effects of electromagnetic, stress, and temperature factors. The study is divided into two parts, one is to propose the calculation model of silicon steel sheet’s permeability;the other is to improve the calculation model of silicon steel sheet’s loss. Then, the magnetic field, stress field, and temperature field of a surface mount high speed permanent magnet motor(SMHSPMSM) are analyzed by finite element method(FEM), and the results under the consideration of magnetic, stress, and temperature factors are brought into the calculation model for calculation. Finally, the accuracy of the calculation model for electromagnetic characteristics of silicon steel sheet is verified by comparing the calculated results with the finite element results.
基金Project supported by the National Natural Science Foundation of China.
文摘Cobalt-protein complexes play an important role in biochemical processes.The structure of the model molecule,Co(H_2O)_3SO_4(phen) has been studied by molecular mechanics.The molecular force field (MM2) parameters have been developed for the particular class of the complexes.
文摘This paper describes the numerical calculations of gaseous reaction flows in a model of gas turbine combustors. The profiles of hydrodynamic and thermodynamic patterns in a three-dimensional combustor model are obtained by solving the governing differential transport equations. The well-established numerical prediction algorithm SIMPLE, the modified k-ε turbulence model and k-ε-g turbulent diffusion flame model have been adopted in computations. The β function has been selected as probability density function. The effect of combustion process on flow patterns has been investigated. The calculated results have been verified by experiments. They are in remarkably good agreement.
基金Supported by the National Natural Science Foundation of China(72140006)GEIDCO Independent Research Project(ZY2023008).
文摘In response to the lack of global quantitative research on the potential and scale prediction of CO_(2) capture,utilization and storage(CCUS)in China under the background of carbon peak and carbon neutrality goals,this study predicts the future economic costs of different links of ccUS technologies and the carbon capture needs of different industries in the scenario of fossil energy continuation.Based on the CO_(2) utilization and storage potential and spatial distribution in China,a cost-scale calculation model for different regions in China in 206o is constructed to predict the whole-process economic cost and its corresponding scale potential of CCUs.The results show that a local+remote storage mode is preferred,together with a local utilization mode,to meet China's 27×10^(8)t/a CO_(2) emission reduction demand under the scenario of fossil energy continuation.Specifically,about 5×10^(8) t CO_(2) emission is reduced by capture utilization,and the whole-process cost is about-1400-200 RMB/t;about 22×10^(8) t CO_(2) emission is reduced by capture storage,and the whole-process cost is about 200-450 RMB/t.According to the model results,it is recommended to develop the chemical utilization industry based on P2X(Power to X,where X is raw material)technology,construct the CcUs industrial cluster,and explore a multi-party win-win cooperation mode.A scheme of national trunk pipeline network connecting areas connecting intensive emission reduction demand areas and target storage areas is suggested.The emission reduction cost of thermal power based on CCUS is calculated to be 0.16 RMB/(kW.h).
基金jointly funded by the National Natural Science Foundation of China(Grant No.42201095)the Natural Science Foundation of Sichuan(Grant No.2022NSFSC1032)。
文摘The use of open-type check dams in mountainous areas has become common practice in order to mitigate the effects of debris flow and extend the service life of engineering structures.The beam dam,a common debris flow control system,has received less attention in research on the impact process of debris flow and check dams compared to solid check dams.Additionally,the estimation of impact pressure in debris flow primarily considers debris flow characteristics,without taking into account the influence of geometric characteristics of the transmission structure.To better understand the impact process of debris flow on beam dams,a series of small-scale debris flow impact tests were conducted in a model flume.Key parameters,including velocity,depth,and impact pressure,were measured.The results show that the maximum impact pressure of debris flow is affected by both the characteristics of the debris flow and the relative opening size of the beam dam.Due to flow and edge occlusion in the middle of the beam dam,the discharge of debris flow is enhanced,resulting in a longer impact process and higher maximum impact pressure.Based on these findings,a calculation model of the maximum impact pressure of debris flow at the midpoint of the middle beam is proposed,which can be used to estimate the impact of debris flow on the discharge part of the beam dam.