The No.601 watermelon (citrullus lanatus) seeds were treated with 25 keV N+ implantation at the dosage of 7.8 ×1016 ions/cm2. After treatment, watermelon seeds were incubated with 380μg/μl pumpkin (Cucubita, ma...The No.601 watermelon (citrullus lanatus) seeds were treated with 25 keV N+ implantation at the dosage of 7.8 ×1016 ions/cm2. After treatment, watermelon seeds were incubated with 380μg/μl pumpkin (Cucubita, maxima Duch) DNA solution at 35 ℃ for 5 hours. By two-generations of selection and resistance screening at seedling stage, one transformed material was selected out, whose rind color is similar to that of the donor pumpkin and whose size of seeds is between that of the donor and the receptor. Using AFLP (amplified fragment length polymorphism) technique, two polymorphic DNA fragments were amplified. This primarily testified that the donor DNA fragments/gene were introduced into the receptor cell and integrated into the genomic DNA of the receptor.展开更多
Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformat...Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformation during the cooling process must be addressed.At present,frequently used semi-empirical kinetics models suffer from huge errors at the beginning of transformation,and most of them fail to exhibit the sigmoidal shape characteristic of transformation curves.To describe the martensitic transformation process accurately,based on the Magee model,we introduced the changes in the nucleation activation energy of martensite with temperature,which led to the varying nucleation rates of this model during martensitic transformation.According to the calculation results,the relative error of the modified model for the martensitic transformation kinetics curves of Fe-C-X(X = Ni,Cr,Mn,Si) alloys reached 9.5% compared with those measured via the thermal expansion method.The relative error was approximately reduced by two-thirds compared with that of the Magee model.The incorporation of nucleation activation energy into the kinetics model contributes to the improvement of its precision.展开更多
Thermoelastic martensitic transformations in shape memory alloys can be modeled on the basis of nonlinear elastic theory.Microstructures of fine phase mixtures are local energy minimizers of the total energy.Using a o...Thermoelastic martensitic transformations in shape memory alloys can be modeled on the basis of nonlinear elastic theory.Microstructures of fine phase mixtures are local energy minimizers of the total energy.Using a one-dimensional effective model,we have shown that such microstructures are inhomogeneous solutions of the nonlinear Euler-Lagrange equation and can appear upon loading or unloading to certain critical conditions,the bifurcation conditions.A hybrid numerical method is utilized to calculate the inhomogeneous solutions with a large number of interfaces.The characteristics of the solutions are clarified by three parameters:the number of interfaces,the interface thickness,and the oscillating amplitude.Approximated analytical expressions are obtained for the interface and inhomogeneity energies through the numerical solutions.展开更多
By detecting and analyzing the variations of energy parameters-torque and temperature field during friction welding, this paper describes that during quasi-stationary heating phase, quite a little mechanical work is t...By detecting and analyzing the variations of energy parameters-torque and temperature field during friction welding, this paper describes that during quasi-stationary heating phase, quite a little mechanical work is transformed into plastic deformation work, thus the efficiency of heat excited by friction is low.展开更多
This paper critically examines research on consumer attitudes and behavior towards solar photovoltaic (PV) and renewable energy technology in Australia. The uptake of renewable energy technology by residential consume...This paper critically examines research on consumer attitudes and behavior towards solar photovoltaic (PV) and renewable energy technology in Australia. The uptake of renewable energy technology by residential consumers in Australia in the past decade has transformed the electricity supply and demand paradigm. Thus, this paper reviews Australian research on consumer behavior, understanding and choices in order to identify gaps in knowledge. As the role of the consumer transforms, there is a critical need to understand the ways that consumers may respond to future energy policies to mitigate unforeseen negative social and economic consequence of programs designed to achieve positive environmental outcomes.展开更多
An energy model for the structure transformation of pile-ups of grain boundary dislocations(GBD)at the triple-junction of the grain boundary of ultrafine-grain materials was proposed.The energy of the pile-up of the G...An energy model for the structure transformation of pile-ups of grain boundary dislocations(GBD)at the triple-junction of the grain boundary of ultrafine-grain materials was proposed.The energy of the pile-up of the GBD in the system was calculated by the energy model,the critical geometric and mechanical conditions for the structure transformation of head dislocation of the pile-up were analyzed,and the influence of the number density of the dislocations and the angle between Burgers vectors of two decomposed dislocations on the transformation mode of head dislocation was discussed.The results show when the GBD is accumulated at triple junction,the head dislocation of the GBD is decomposed into two Burgers vectors of these dislocations unless the angle between the two vectors is less than 90°,and the increase of applied external stress can reduce the energy barrier of the dislocation decomposition.The mechanism that the ultrafine-grained metal material has both high strength and plasticity owing to the structure transformation of the pile-up of the GBD at the triple junction of the grain boundary is revealed.展开更多
Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large ...Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large public buildings energy-saving is an effective way both at home and abroad. EPC mode has obvious characteristics for the ESCO and the customers, it can meet the basic requirements of large public buildings energy-saving, such as the width of funding sources, program specifi cation, advanced technology, information fl ow and management level higher, etc. Under the condition of market economy, it also provides a broad platform for the ESCO implements building energy saving transformation, which is conducive to the realization of the win-win cooperation between the parties, and to promote the healthy development of the existing large public building energy saving reconstruction.展开更多
The energy transformation and efficiency is now a hot topic among researches of scientific drilling into fault zones (Tanaka et al., 2006; Ma et al., 2006). This study conducted temperature measurements and fault go...The energy transformation and efficiency is now a hot topic among researches of scientific drilling into fault zones (Tanaka et al., 2006; Ma et al., 2006). This study conducted temperature measurements and fault gouge particle analysis of borehole WFSD-1 from the Wenchuan Earthquake Fault Science Drilling Project (WFSD), and discussed the earthquake energy budget. The research progress is illuminated as follows.展开更多
A New Round of Industrial Revolution Promotes Energy Transformation Energy serves as a critical physical basis for sustaining human society and the development of civi lization."Energy transformation"refers ...A New Round of Industrial Revolution Promotes Energy Transformation Energy serves as a critical physical basis for sustaining human society and the development of civi lization."Energy transformation"refers to fundamental changes in the structure of the energy system.It is not only a process of the energy industry itself but also involves systematic problems concerning human living environments and society.Energy transformation is usually accompanied by an industrial revolution.After James Watt invented the steam engine in 1770,the first Industrial Revolution began.展开更多
The peculiarities of energy dissipation transferred by solitary waves on defects such as freesurface, grain boundary, region with high concentration of vacancies are studied. One of theways of description of the long ...The peculiarities of energy dissipation transferred by solitary waves on defects such as freesurface, grain boundary, region with high concentration of vacancies are studied. One of theways of description of the long range effect taking place at ion implantation in metallic materialsis suggested.展开更多
Urban energy transformation is important to promote China’s energy transformation,to facilitate ecological civilization construction,and to achieve the goal of carbon peak and carbon neutrality.In recent years,Huzhou...Urban energy transformation is important to promote China’s energy transformation,to facilitate ecological civilization construction,and to achieve the goal of carbon peak and carbon neutrality.In recent years,Huzhou,a city of Zhejiang Province,has actively promoted the"ecology+power"city construction.It has explored an innovative mode of urban energy transformation and gained rich practical experience,which has widely attracted attention at home and abroad.Based on field research,this paper makes a comprehensive collation of policies and practical experience of Huzhou’s"ecology+power"mode and summarizes the mode characteristics and promotion value of Huzhou’s urban energy transformation.Finally,taking Huzhou as a sample,we put forward some policy suggestions of China’s urban energy transformation.展开更多
"Economic transformation"has become the main path to promote China's social and economic development,and many regions have increased the importance and attention to"economic transformation",and..."Economic transformation"has become the main path to promote China's social and economic development,and many regions have increased the importance and attention to"economic transformation",and the Southwest region is no exception.Many cities in Southwest China are developing new energy sources to promote economic development and economic transformation.Economic transformation and economic development in Southwest China are mutually influencing and interacting,while energy development in Southwest China and its local economic development are mutually promoting and influencing,so economic transformation also affects energy demand and development in Southwest China.The importance of economic transformation should be taken into consideration.展开更多
Let LE(G) denote the Laplacian energy of a graph G. In this paper the xyz-transformations G^(xyz) of an r-regular graph G for x,y,z∈{0,1, +,-} are considered. The explicit formulas of LE(G^(xyz)) are presented in ter...Let LE(G) denote the Laplacian energy of a graph G. In this paper the xyz-transformations G^(xyz) of an r-regular graph G for x,y,z∈{0,1, +,-} are considered. The explicit formulas of LE(G^(xyz)) are presented in terms of r,the number of vertices of G for any positive integer r and x,y,z∈{ 0,1},and also for r = 2 and all x,y,z∈{0,1,+,-}. Some Laplacian equienergetic pairs of G^(xyz) for r = 2 and x,y,z∈{0,1, +,-} are obtained. This also provides several ways to construct infinitely many pairs of Laplacian equienergetic graphs.展开更多
Supposing carbon contents of ferrite phases in pearlite precipitating from austenite in multicomponent steel at temperature T and in Fe-C ystem at T' are the same the pearlite formation temperature diference, can ...Supposing carbon contents of ferrite phases in pearlite precipitating from austenite in multicomponent steel at temperature T and in Fe-C ystem at T' are the same the pearlite formation temperature diference, can be calculated from the FeX phase diagrams and the equilibrium temperature Al. Using Tp and Fe-C binary thermodynamic model, the driving forces for phase transformation from austenite to pearlite in multicomponent steels have been successfully calculated. Through the combination of simplified Zener and Hillert's model for pearlite growth with Johnson-Mehl equation, using data from known TTT diagrams, the interfacial energy parameter and activation energy for pearlite formation can be determined and expressed as functions of chemical composition in steels by regression analysis. The calculated starting curves of pearlitic transformation in some commercial steels agree well with the experimental data.展开更多
The reduction of titanomagnetite(TTM) ironsand, which contains 11.41wt% TiO_2 and 55.63wt% total Fe, by graphite was performed using a thermogravimetric analysis system under an argon gas atmosphere at 1423–1623 K....The reduction of titanomagnetite(TTM) ironsand, which contains 11.41wt% TiO_2 and 55.63wt% total Fe, by graphite was performed using a thermogravimetric analysis system under an argon gas atmosphere at 1423–1623 K. The behavior and effects of titanium in TTM ironsand during the reduction process were investigated by means of thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. During the reduction procedure, the titanium concentrated in the slag phase, where the phase transformation followed this sequence: Fe O + FeTiO_3 → Fe_2 TiO_4 → FeTiO_3 → FeTi_2O_5 → TiO_2. The calculated results for the reduction kinetics showed that the carbothermic reduction was controlled by the diffusion of ions through the product layer. Furthermore, the apparent activation energy was 170.35 k J·mol^(-1).展开更多
A new micromechanics constitutive model for pure dilatant transformation plasticity of structure ceramics is proposed in this paper.Based on the thermodynamics,micromechanics and microscale t→ m trans- formation mech...A new micromechanics constitutive model for pure dilatant transformation plasticity of structure ceramics is proposed in this paper.Based on the thermodynamics,micromechanics and microscale t→ m trans- formation mechanism analysis of the TZP and PSZ ZrO2-containing ceramics,an analytic expressions of the Helmholtz and complementary free energy of the constitutive element for the case of pure dilatant transforma- tion is derived for the first time in a self-consistent manner.By the analysis of energy dissipation in the for- ward and reverse transformations,the mieromechanics constitutive law is derived in the framework of Hill-Rice’s internal variable constitutive theory.展开更多
Photovoltaic(PV)systems are environmentally friendly,generate green energy,and receive support from policies and organizations.However,weather fluctuations make large-scale PV power integration and management challeng...Photovoltaic(PV)systems are environmentally friendly,generate green energy,and receive support from policies and organizations.However,weather fluctuations make large-scale PV power integration and management challenging despite the economic benefits.Existing PV forecasting techniques(sequential and convolutional neural networks(CNN))are sensitive to environmental conditions,reducing energy distribution system performance.To handle these issues,this article proposes an efficient,weather-resilient convolutional-transformer-based network(CT-NET)for accurate and efficient PV power forecasting.The network consists of three main modules.First,the acquired PV generation data are forwarded to the pre-processing module for data refinement.Next,to carry out data encoding,a CNNbased multi-head attention(MHA)module is developed in which a single MHA is used to decode the encoded data.The encoder module is mainly composed of 1D convolutional and MHA layers,which extract local as well as contextual features,while the decoder part includes MHA and feedforward layers to generate the final prediction.Finally,the performance of the proposed network is evaluated using standard error metrics,including the mean squared error(MSE),root mean squared error(RMSE),and mean absolute percentage error(MAPE).An ablation study and comparative analysis with several competitive state-of-the-art approaches revealed a lower error rate in terms of MSE(0.0471),RMSE(0.2167),and MAPE(0.6135)over publicly available benchmark data.In addition,it is demonstrated that our proposed model is less complex,with the lowest number of parameters(0.0135 M),size(0.106 MB),and inference time(2 ms/step),suggesting that it is easy to integrate into the smart grid.展开更多
Partial thermoelastic martensitic transformations have been studied by calorimetry on CuAlNi single crystals with special methods. The chemical enthalpy change, the elastic energy stored at the interfaces or inside of...Partial thermoelastic martensitic transformations have been studied by calorimetry on CuAlNi single crystals with special methods. The chemical enthalpy change, the elastic energy stored at the interfaces or inside of the martensite and the energy dissipated in acoustic emission were calculated for a partial transformation; the relationship among them was studied based on measured latent heat and transformation temperatures. The influence of specimen shape on the stored elastic energy was evaluated and discussed.展开更多
The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collectin...The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.展开更多
Based on strain signals, a new time-domain methodology for detecting the beam local damage has been developed. The pseudo strain energy density (PSED) is defined and used to build two major damage indexes, the avera...Based on strain signals, a new time-domain methodology for detecting the beam local damage has been developed. The pseudo strain energy density (PSED) is defined and used to build two major damage indexes, the average pseudo strain energy density (APSED) and the average pseudo strain energy density rate (APSEDR). Probability and mathematical statistics are utilized to derive a standardized damage index. Furthermore, by applying the analytic relation between the strain energy release rate and the stress intensity factor, an analytic solution of crack depth is derived. For the dynamic strain signals, the wavelet packet transform is used to pre-process measured data. Finally, a numerical simulation indicates that this method can effectively identify the damage location and its absolute severity.展开更多
基金This work was supported by National Key Project (96-538-01-01).
文摘The No.601 watermelon (citrullus lanatus) seeds were treated with 25 keV N+ implantation at the dosage of 7.8 ×1016 ions/cm2. After treatment, watermelon seeds were incubated with 380μg/μl pumpkin (Cucubita, maxima Duch) DNA solution at 35 ℃ for 5 hours. By two-generations of selection and resistance screening at seedling stage, one transformed material was selected out, whose rind color is similar to that of the donor pumpkin and whose size of seeds is between that of the donor and the receptor. Using AFLP (amplified fragment length polymorphism) technique, two polymorphic DNA fragments were amplified. This primarily testified that the donor DNA fragments/gene were introduced into the receptor cell and integrated into the genomic DNA of the receptor.
基金financially supported by the National Natural Science Foundation of China(No.U2102212)the Shanghai Rising-Star Program(No.21QA1403200)。
文摘Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformation during the cooling process must be addressed.At present,frequently used semi-empirical kinetics models suffer from huge errors at the beginning of transformation,and most of them fail to exhibit the sigmoidal shape characteristic of transformation curves.To describe the martensitic transformation process accurately,based on the Magee model,we introduced the changes in the nucleation activation energy of martensite with temperature,which led to the varying nucleation rates of this model during martensitic transformation.According to the calculation results,the relative error of the modified model for the martensitic transformation kinetics curves of Fe-C-X(X = Ni,Cr,Mn,Si) alloys reached 9.5% compared with those measured via the thermal expansion method.The relative error was approximately reduced by two-thirds compared with that of the Magee model.The incorporation of nucleation activation energy into the kinetics model contributes to the improvement of its precision.
基金supported by the National Natural Science Foundation of China(Grants 11461161008 and 11272092)
文摘Thermoelastic martensitic transformations in shape memory alloys can be modeled on the basis of nonlinear elastic theory.Microstructures of fine phase mixtures are local energy minimizers of the total energy.Using a one-dimensional effective model,we have shown that such microstructures are inhomogeneous solutions of the nonlinear Euler-Lagrange equation and can appear upon loading or unloading to certain critical conditions,the bifurcation conditions.A hybrid numerical method is utilized to calculate the inhomogeneous solutions with a large number of interfaces.The characteristics of the solutions are clarified by three parameters:the number of interfaces,the interface thickness,and the oscillating amplitude.Approximated analytical expressions are obtained for the interface and inhomogeneity energies through the numerical solutions.
文摘By detecting and analyzing the variations of energy parameters-torque and temperature field during friction welding, this paper describes that during quasi-stationary heating phase, quite a little mechanical work is transformed into plastic deformation work, thus the efficiency of heat excited by friction is low.
文摘This paper critically examines research on consumer attitudes and behavior towards solar photovoltaic (PV) and renewable energy technology in Australia. The uptake of renewable energy technology by residential consumers in Australia in the past decade has transformed the electricity supply and demand paradigm. Thus, this paper reviews Australian research on consumer behavior, understanding and choices in order to identify gaps in knowledge. As the role of the consumer transforms, there is a critical need to understand the ways that consumers may respond to future energy policies to mitigate unforeseen negative social and economic consequence of programs designed to achieve positive environmental outcomes.
基金financial supports from the National Natural Science Foundation of China(Nos.51161003,51561031)the Natural Science Foundation of Guangxi,China(No.2018GXNSFAA138150)。
文摘An energy model for the structure transformation of pile-ups of grain boundary dislocations(GBD)at the triple-junction of the grain boundary of ultrafine-grain materials was proposed.The energy of the pile-up of the GBD in the system was calculated by the energy model,the critical geometric and mechanical conditions for the structure transformation of head dislocation of the pile-up were analyzed,and the influence of the number density of the dislocations and the angle between Burgers vectors of two decomposed dislocations on the transformation mode of head dislocation was discussed.The results show when the GBD is accumulated at triple junction,the head dislocation of the GBD is decomposed into two Burgers vectors of these dislocations unless the angle between the two vectors is less than 90°,and the increase of applied external stress can reduce the energy barrier of the dislocation decomposition.The mechanism that the ultrafine-grained metal material has both high strength and plasticity owing to the structure transformation of the pile-up of the GBD at the triple junction of the grain boundary is revealed.
基金supported by the National Natural Foundation of China (Grant No. 71171141)Project of the Ministry of Housing and Urban-Rural Development (Grant No. 2013-R1-14)the Tianjin Municipal Social Science Planning Project (Grant No. TJGLHQ1403)
文摘Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large public buildings energy-saving is an effective way both at home and abroad. EPC mode has obvious characteristics for the ESCO and the customers, it can meet the basic requirements of large public buildings energy-saving, such as the width of funding sources, program specifi cation, advanced technology, information fl ow and management level higher, etc. Under the condition of market economy, it also provides a broad platform for the ESCO implements building energy saving transformation, which is conducive to the realization of the win-win cooperation between the parties, and to promote the healthy development of the existing large public building energy saving reconstruction.
基金supported by the Science and Technology Project of China (No.WFSD-0003)
文摘The energy transformation and efficiency is now a hot topic among researches of scientific drilling into fault zones (Tanaka et al., 2006; Ma et al., 2006). This study conducted temperature measurements and fault gouge particle analysis of borehole WFSD-1 from the Wenchuan Earthquake Fault Science Drilling Project (WFSD), and discussed the earthquake energy budget. The research progress is illuminated as follows.
文摘A New Round of Industrial Revolution Promotes Energy Transformation Energy serves as a critical physical basis for sustaining human society and the development of civi lization."Energy transformation"refers to fundamental changes in the structure of the energy system.It is not only a process of the energy industry itself but also involves systematic problems concerning human living environments and society.Energy transformation is usually accompanied by an industrial revolution.After James Watt invented the steam engine in 1770,the first Industrial Revolution began.
文摘The peculiarities of energy dissipation transferred by solitary waves on defects such as freesurface, grain boundary, region with high concentration of vacancies are studied. One of theways of description of the long range effect taking place at ion implantation in metallic materialsis suggested.
文摘Urban energy transformation is important to promote China’s energy transformation,to facilitate ecological civilization construction,and to achieve the goal of carbon peak and carbon neutrality.In recent years,Huzhou,a city of Zhejiang Province,has actively promoted the"ecology+power"city construction.It has explored an innovative mode of urban energy transformation and gained rich practical experience,which has widely attracted attention at home and abroad.Based on field research,this paper makes a comprehensive collation of policies and practical experience of Huzhou’s"ecology+power"mode and summarizes the mode characteristics and promotion value of Huzhou’s urban energy transformation.Finally,taking Huzhou as a sample,we put forward some policy suggestions of China’s urban energy transformation.
文摘"Economic transformation"has become the main path to promote China's social and economic development,and many regions have increased the importance and attention to"economic transformation",and the Southwest region is no exception.Many cities in Southwest China are developing new energy sources to promote economic development and economic transformation.Economic transformation and economic development in Southwest China are mutually influencing and interacting,while energy development in Southwest China and its local economic development are mutually promoting and influencing,so economic transformation also affects energy demand and development in Southwest China.The importance of economic transformation should be taken into consideration.
基金National Natural Science Foundation of China(No.11371086)the Fund of Science and Technology Commission of Shanghai Municipality,China(No.13ZR1400100)
文摘Let LE(G) denote the Laplacian energy of a graph G. In this paper the xyz-transformations G^(xyz) of an r-regular graph G for x,y,z∈{0,1, +,-} are considered. The explicit formulas of LE(G^(xyz)) are presented in terms of r,the number of vertices of G for any positive integer r and x,y,z∈{ 0,1},and also for r = 2 and all x,y,z∈{0,1,+,-}. Some Laplacian equienergetic pairs of G^(xyz) for r = 2 and x,y,z∈{0,1, +,-} are obtained. This also provides several ways to construct infinitely many pairs of Laplacian equienergetic graphs.
文摘Supposing carbon contents of ferrite phases in pearlite precipitating from austenite in multicomponent steel at temperature T and in Fe-C ystem at T' are the same the pearlite formation temperature diference, can be calculated from the FeX phase diagrams and the equilibrium temperature Al. Using Tp and Fe-C binary thermodynamic model, the driving forces for phase transformation from austenite to pearlite in multicomponent steels have been successfully calculated. Through the combination of simplified Zener and Hillert's model for pearlite growth with Johnson-Mehl equation, using data from known TTT diagrams, the interfacial energy parameter and activation energy for pearlite formation can be determined and expressed as functions of chemical composition in steels by regression analysis. The calculated starting curves of pearlitic transformation in some commercial steels agree well with the experimental data.
基金financially supported by National Basic Research Program of China(No.2012CB720400)the National Natural Science Foundation of China(No.51504216)
文摘The reduction of titanomagnetite(TTM) ironsand, which contains 11.41wt% TiO_2 and 55.63wt% total Fe, by graphite was performed using a thermogravimetric analysis system under an argon gas atmosphere at 1423–1623 K. The behavior and effects of titanium in TTM ironsand during the reduction process were investigated by means of thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. During the reduction procedure, the titanium concentrated in the slag phase, where the phase transformation followed this sequence: Fe O + FeTiO_3 → Fe_2 TiO_4 → FeTiO_3 → FeTi_2O_5 → TiO_2. The calculated results for the reduction kinetics showed that the carbothermic reduction was controlled by the diffusion of ions through the product layer. Furthermore, the apparent activation energy was 170.35 k J·mol^(-1).
基金The project is supported by the National Natural Science Foundation of Chin
文摘A new micromechanics constitutive model for pure dilatant transformation plasticity of structure ceramics is proposed in this paper.Based on the thermodynamics,micromechanics and microscale t→ m trans- formation mechanism analysis of the TZP and PSZ ZrO2-containing ceramics,an analytic expressions of the Helmholtz and complementary free energy of the constitutive element for the case of pure dilatant transforma- tion is derived for the first time in a self-consistent manner.By the analysis of energy dissipation in the for- ward and reverse transformations,the mieromechanics constitutive law is derived in the framework of Hill-Rice’s internal variable constitutive theory.
基金supported by the National Research Foundation of Korea (NRF)grant funded by the Korean government (MSIT) (No.2019M3F2A1073179).
文摘Photovoltaic(PV)systems are environmentally friendly,generate green energy,and receive support from policies and organizations.However,weather fluctuations make large-scale PV power integration and management challenging despite the economic benefits.Existing PV forecasting techniques(sequential and convolutional neural networks(CNN))are sensitive to environmental conditions,reducing energy distribution system performance.To handle these issues,this article proposes an efficient,weather-resilient convolutional-transformer-based network(CT-NET)for accurate and efficient PV power forecasting.The network consists of three main modules.First,the acquired PV generation data are forwarded to the pre-processing module for data refinement.Next,to carry out data encoding,a CNNbased multi-head attention(MHA)module is developed in which a single MHA is used to decode the encoded data.The encoder module is mainly composed of 1D convolutional and MHA layers,which extract local as well as contextual features,while the decoder part includes MHA and feedforward layers to generate the final prediction.Finally,the performance of the proposed network is evaluated using standard error metrics,including the mean squared error(MSE),root mean squared error(RMSE),and mean absolute percentage error(MAPE).An ablation study and comparative analysis with several competitive state-of-the-art approaches revealed a lower error rate in terms of MSE(0.0471),RMSE(0.2167),and MAPE(0.6135)over publicly available benchmark data.In addition,it is demonstrated that our proposed model is less complex,with the lowest number of parameters(0.0135 M),size(0.106 MB),and inference time(2 ms/step),suggesting that it is easy to integrate into the smart grid.
文摘Partial thermoelastic martensitic transformations have been studied by calorimetry on CuAlNi single crystals with special methods. The chemical enthalpy change, the elastic energy stored at the interfaces or inside of the martensite and the energy dissipated in acoustic emission were calculated for a partial transformation; the relationship among them was studied based on measured latent heat and transformation temperatures. The influence of specimen shape on the stored elastic energy was evaluated and discussed.
基金This work was supported by the Ministry of Science and Technology(No.2020YFE0202001)by the National Natural Science Foundation of China(Nos.11961141004 and 12205160)Tsinghua University Initiative Scientific Research Program.
文摘The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.
基金The National Natural Science Foundation of China (Nos.50778077 and 50608036)
文摘Based on strain signals, a new time-domain methodology for detecting the beam local damage has been developed. The pseudo strain energy density (PSED) is defined and used to build two major damage indexes, the average pseudo strain energy density (APSED) and the average pseudo strain energy density rate (APSEDR). Probability and mathematical statistics are utilized to derive a standardized damage index. Furthermore, by applying the analytic relation between the strain energy release rate and the stress intensity factor, an analytic solution of crack depth is derived. For the dynamic strain signals, the wavelet packet transform is used to pre-process measured data. Finally, a numerical simulation indicates that this method can effectively identify the damage location and its absolute severity.