In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation ...In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation for the KdV equation to such coupled KdV system.Then from a trivial seed solution,we construct soliton solutions.We also give a nonlinear superposition formula,which allows us to generate multi-soliton solutions.展开更多
Al-doped manganese dioxide(MnO_(2))was synthesized by simple hydrothermal method,and a controllable phase transition of the MnO_(2)crystal phase fromβtoδwas achieved.The effects of Al doping concentration on the str...Al-doped manganese dioxide(MnO_(2))was synthesized by simple hydrothermal method,and a controllable phase transition of the MnO_(2)crystal phase fromβtoδwas achieved.The effects of Al doping concentration on the structure and electrochemical properties of electrode materials were studied in detail.The results show that the controlled synthesis requires a synergy between KMnO_(4),MnCl_(2)and AlCl_(3),and that Al^(3+)plays an important role.Compared with the pure phase MnO_(2),the crystallinity of Al-doped MnO_(2)decreases and the specific surface area increases,which provides more active sites for the electrode material.When 3 mmol Al^(3+)is added,the prepared MnO_(2)-3 has the largest specific capacitance and the highest rate performance.The energy density of the asymmetric supercapacitor(ASC)with MnO_(2)-3 as the positive electrode and activated carbon(AC)as the negative electrode can reach 18.4 W·h/kg at the power density of 400 W/kg,and the capacity can maintain 90%of the initial value after 20000 cycles,indicating that Al-doped MnO_(2)has certain practical application value.This study provides favorable guidance for MnO_(2)as a high performance electrode material.展开更多
Heat transfers at the interface of adjacent saturated soil primarily through the soil particles and the water in the voids.The presence of water induces the contraction of heat flow lines at the interface,leading to t...Heat transfers at the interface of adjacent saturated soil primarily through the soil particles and the water in the voids.The presence of water induces the contraction of heat flow lines at the interface,leading to the emergence of the thermal contact resistance effect.In this paper,four thermal contact models were developed to predict the thermal contact resistance at the interface of multilayered saturated soils.Based on the theory of thermal-hydro-mechanical coupling,semi-analytical solutions of thermal consolidation subjected to time-dependent heating and loading were obtained by employing Laplace transform and its inverse transformation.Thermal consolidation characteristics of multilayered saturated soils under four different thermal contact models were discussed,and the effects of thermal resistance coefficient,partition thermal contact coefficient,and temperature amplitude on the thermal consolidation process were investigated.The outcomes indicate that the general thermal contact model results in the most pronounced thermal gradient at the interface,which can be degenerated to the other three thermal contact models.The perfect thermal contact model overestimates the deformation of the saturated soil during the thermal consolidation.Moreover,the effect of temperature on consolidation properties decreases gradually with increasing interfacial contact thermal resistance.展开更多
The development and wide application of genetic transformation for cotton improvement are restrained by the unresolved problem of genotype dependence in regeneration in vitro.High embryogenic and regenerative potentia...The development and wide application of genetic transformation for cotton improvement are restrained by the unresolved problem of genotype dependence in regeneration in vitro.High embryogenic and regenerative potential have been obtained for limited number of Coker type genotypes。展开更多
Judicial procedure,as a legal method to exercise the jurisdiction,has become an important element of the legal system construction.To improve the judicial procedure,legal procedure must be strictly complied with to co...Judicial procedure,as a legal method to exercise the jurisdiction,has become an important element of the legal system construction.To improve the judicial procedure,legal procedure must be strictly complied with to complete the proceedings and the legitimate interests of the entities of the parties concerned and participants must be respected and protected.The reform of the judicial procedure system shall be strictly promoted and orderly carried out through scientific and reasonable setting,positive guidance in equal participation of both parties of the proceedings while making use of the security mechanism of supervision and restriction.展开更多
"Law and literature " comes from an American radical law school of the1970 s,and it was then considered a campaign,thus the school became one of the most post-modernistic schools of thought. Due to its weste..."Law and literature " comes from an American radical law school of the1970 s,and it was then considered a campaign,thus the school became one of the most post-modernistic schools of thought. Due to its western theoretic background,it is necessary to interpret its context; in other words,the "Law and literature"problems shall be interpreted in the Chinese context,which can also provide much inspiration and reference for the construction of China's legal system.展开更多
The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literat...The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literature studies.In this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical materials.The linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal analyser.The thermal decomposition curves are decoupled by advanced thermokinetics software.The thermal decomposition and kinetic parameters before and after decoupling are calculated.The results of TG experiment show that both NQ and RDX began to lose mass during the endothermic stage.The endothermic melting and exothermic decomposition of NQ and RDX are coupled within this stage.The coupling effect has different degrees of influence on its initial decomposition temperature and safety parameters.Compared with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling decrease.The self-accelerating decomposition temperature increases,and internal thermal runaway time decreases.In the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。展开更多
In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequen...In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequence of L^(1)functions converging to the given function and verifying their representation in the form of Fourier transform to establish the desired result of the given function.Applying this main result,we further generalize the Paley-Wiener theorem for band-limited functions to the analytic function spaces L^(p)(0<p<∞)with general weights.展开更多
The room temperature phase diagram of Al-Zn-Cu system is the important basis for judging the phase constituents of the materials at the usage condition. New results about the room temperature phase diagram of the low ...The room temperature phase diagram of Al-Zn-Cu system is the important basis for judging the phase constituents of the materials at the usage condition. New results about the room temperature phase diagram of the low copper side in the Al-Zn-Cu systems have been shown in this study. Miscibility gap of fcc phase in the Al-Zn-Cu system has also been studied by experimental diffusion-couple method and thermodynamic calculation. Properties of this miscibility gap have been known. It is practically significant for the study on the aging behavior and for the control of the microstructure and properties of the Al alloys with Zn and Cu element.展开更多
In the present study,molecular dynamic simulation(MD)was used to investigate the plastic deformation process of the Fe-Mn alloys with different Mn contents.The influences of Mn contents ranging from 10%to 30%(at%)on t...In the present study,molecular dynamic simulation(MD)was used to investigate the plastic deformation process of the Fe-Mn alloys with different Mn contents.The influences of Mn contents ranging from 10%to 30%(at%)on the deformation behavior and the controlling mechanism of the Fe-base alloys were analyzed.The results show that phase transformations and{112}<111>_(BCC)deformation twinning occur in all Fe-Mn alloys but follow different deformation paths.In the Fe-10%Mn alloy the deformation twinning mechanism obeys the FCC-related path,the Fe-20%Mn alloy involves both the FCC-and HCP-related paths,and the deformation of the Fe-30%Mn alloy is dominated by the HCP-related twinning path.The addition of Mn can increase the stacking fault energy and retard the activation of slip systems as well as the formation of stacking faults.Thus,a higher content of Mn can delay the FCC®ε-martensite and the subsequentε-martensite®BCC phase transition at the intersection of twoε-martensitic bands.Therefore,the addition of Mn alloying element increases the yield strength and reduces the elastic modulus of the Fe-Mn alloys.The formation of deformation twins will contribute to the work-hardening effect and delay the necking and fracture of alloys.It is expected that the results in the present study will provide theoretical reference for the design and optimization of high-performance steels.展开更多
Model-based system-of-systems(SOS)engineering(MBSoSE)is becoming a promising solution for the design of SoS with increasing complexity.However,bridging the models from the design phase to the simulation phase poses si...Model-based system-of-systems(SOS)engineering(MBSoSE)is becoming a promising solution for the design of SoS with increasing complexity.However,bridging the models from the design phase to the simulation phase poses significant challenges and requires an integrated approach.In this study,a unified requirement modeling approach is proposed based on unified architecture framework(UAF).Theoretical models are proposed which compose formalized descriptions from both topdown and bottom-up perspectives.Based on the description,the UAF profile is proposed to represent the SoS mission and constituent systems(CS)goal.Moreover,the agent-based simulation information is also described based on the overview,design concepts,and details(ODD)protocol as the complement part of the SoS profile,which can be transformed into different simulation platforms based on the eXtensible markup language(XML)technology and model-to-text method.In this way,the design of the SoS is simulated automatically in the early design stage.Finally,the method is implemented and an example is given to illustrate the whole process.展开更多
This study proposes a general imperfect thermal contact model to predict the thermal contact resistance at the interface among multi-layered composite structures.Based on the Green-Lindsay(GL)thermoelastic theory,semi...This study proposes a general imperfect thermal contact model to predict the thermal contact resistance at the interface among multi-layered composite structures.Based on the Green-Lindsay(GL)thermoelastic theory,semi analytical solutions of temperature increment and displacement of multi-layered composite structures are obtained by using the Laplace transform method,upon which the effects of thermal resistance coefficient,partition coefficient,thermal conductivity ratio and heat capacity ratio on the responses are studied.The results show that the generalized imperfect thermal contact model can realistically describe the imperfect thermal contact problem.Accordingly,it may degenerate into other thermal contact models by adjusting the thermal resistance coefficient and partition coefficient.展开更多
The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of manufacture.However,to-date,laboratory testi...The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of manufacture.However,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the Convention.In this project,portable FTIR and Raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within Australia.While both FTIR and Raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FTIR and Raman spectra were matched the relevant explosive(RDX or PETN),rather than the DMDNB taggant.For all three plastic explosives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex Convention.Additional testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the solid.Thus,while both FTIR and Raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for detection.It is likely that similar results would be found for other taggants stipulated by the Marplex Convention,given they are also present in concentrations less than 1%.展开更多
Martensitic transformation behavior was studied for zirconia containing 4%~10% CeO2 (in mole fraction) by using a dilatometric method. The Ms (Martensite start temperature) decreased near linearly with increasing CeO...Martensitic transformation behavior was studied for zirconia containing 4%~10% CeO2 (in mole fraction) by using a dilatometric method. The Ms (Martensite start temperature) decreased near linearly with increasing CeO2. Different transformation modes were observed depending on the composition and cooling rate. ZrO2 containing 6% CeO2 showed isothermal transformation behavior, whereas ZrO2 containing 9% and 10% CeO2 showed athermal transformation behavior. However, ZrO2 containing 8% CeO2 showed either isothermal or athermal transformations behavior depending on the cooling rate. A TTT (Time-Temperature-Transformation) diagram was proposed for ZrO2 containing 8% CeO2.展开更多
Based on current theories of diffusion and creep cavity closure at high temperature, a theoretical analysis of phase transformation diffusion bonding for T8/T8 eutectoid steel is carried out. The diffusion bonding is ...Based on current theories of diffusion and creep cavity closure at high temperature, a theoretical analysis of phase transformation diffusion bonding for T8/T8 eutectoid steel is carried out. The diffusion bonding is mainly described as two-stage process: Ⅰ The interfacial cavity with shape change from diamond to cylinder.Ⅱ The radius of the cylindrical cavity are reduced and eliminated gradually. A new theoretical model is established for the process of transformation superplastic diffusion bonding (TSDB) on the basis of a theoretical model for isothermal superplastic diffusion. The model can predict the bonding quality which is affected by technological parameters, such as limit cycling temperature, the compressive stress, the numbers of thermal cycles and temperature cycling through the phase transformation in the thermal cycling and so on. Results show that the maximum temperature, the compressive stress, the numbers of thermal cycles and the rate of temperature changing speed in the thermal cycling have an important influence on TSDB process. Meanwhile, reasonable technological parameters chosen from theoretical analysis is in good agreement with those obtained from experimental results.展开更多
This paper proposes an efficient scheme to reduce the pre-correlation bandwidth effect in the global navigation satellite system(GNSS)receiver filtering process.It is mainly based on the application of a spectral tran...This paper proposes an efficient scheme to reduce the pre-correlation bandwidth effect in the global navigation satellite system(GNSS)receiver filtering process.It is mainly based on the application of a spectral transformation to the satellite-emitted signal that effectively reduces its band.At the receiver's end,this operation causes the spreading of noise over a much wider band than that used by the radio frequency stage.Consequently,the resulting auto-correlation function in the acquisition process acquires properties that enhance considerably the performance of the receiver in the presence of the multipath and noise disturbing phenomena.The simulation results demonstrate that the proposed method is a plausible solution for both multipath and noise problems in the GNSS applications for any limited value of the pre-correlation bandwidth in the receiver filter.展开更多
Sulfur speciation transformation during bioleaching of pyrite-containing sphalerite concentrate by thermophile Sulfolobus metallicus (S. metallicus) at 65 ℃ was investigated by X-ray diffraction (XRD), diffuse re...Sulfur speciation transformation during bioleaching of pyrite-containing sphalerite concentrate by thermophile Sulfolobus metallicus (S. metallicus) at 65 ℃ was investigated by X-ray diffraction (XRD), diffuse reflectance Fourier transform infrared spectroscopy (FT-IR) and sulfur K-edge X-ray absorption near edge structure spectroscopy (XANES). The results show that the presence of S. metallicus effectively enhances the dissolution of the mineral. The yield of zinc increases from 0.5 g/L in sterile control to 2.7 g/L in bioleaching. The pyrite in the concentrate facilitates zinc dissolution in the early stage, but has hindrance role in the late stage for the formation of jarosite. Sulfur speciation analyses show that jarosite and elemental sulfur are main products in bioleaching process, and the accumulation ofjarosite is mainly responsible for the decline of leaching efficiency.展开更多
Since the advent of transgenic technology,the incorporation of gene(s)encoding traits of economic importance in cotton is being practiced worldwide.However,factors like recalcitrant nature of cotton cultivars,in vitro...Since the advent of transgenic technology,the incorporation of gene(s)encoding traits of economic importance in cotton is being practiced worldwide.However,factors like recalcitrant nature of cotton cultivars,in vitro regeneration via tissue culture(especially via somatic embryogenesis),genotype dependency,long and toilsome protocols impede the pace of development of transgenic cotton.Besides that,types and age of explants,media composition,plant growth regulators and other environmental factors affect in vitro cotton regeneration significantly.The studies of genetic control of in vitro regeneration in plants have elucidated the role of certain transcription factor genes that are induced and expressed during somatic embryogenesis.Among these transcription factors,BABY BOOM(BBM)plays a very important role in signal transduction pathway,leading to cell differentiation and somatic embryos formation.The role of BBM has been established in plant cell proliferation,growth and development even without exogenous growth regulators.This review intends to provide an informative summary of regeneration and transformation problems in cotton and the latest developments in utilization of BBM transcription factors in cotton.We believe that the use of BBM will not only ease cotton genetic improvement but will also accelerate cotton breeding programmes.展开更多
Financing difficulties have always been one of the bottlenecks restricting the development of"three rural".The core to solve the difficulties is to seek financing collaterals that in line with the law and wi...Financing difficulties have always been one of the bottlenecks restricting the development of"three rural".The core to solve the difficulties is to seek financing collaterals that in line with the law and with the value able to be effectively evaluated.Besides,the law confirmation of the mortgage financing's form for Rural Land ManagementRight(RLMR)is the primary prerequisite for rural land financing.With the continuous advancement of rural revitalization strategy,the rural land reform with the main content of"three powers separation"has paid more attention to the functions of RLMR financing.Due to the lack of supply of existing laws,there are still certain legal risks in the financing of RLMR.Based on rural revitalization strategy,this paper made an in-depth analysis of the causes of financing risk of RLMR.Furthermore,we put forward some possible paths to legalize this right.展开更多
Under the dual driven forces of soaring disputes and national policy,the dispute resolution ecosystem of China showed the mediation centralism,and the revival of mediation presented the characteristics of adversary sy...Under the dual driven forces of soaring disputes and national policy,the dispute resolution ecosystem of China showed the mediation centralism,and the revival of mediation presented the characteristics of adversary system.In order to comply with the modern rule of law system,the traditional mediation is incorporated into the modern legal system through the three-level transformation of"discipline of laws","introduction of procedures"and"specialized cultivation",which was promoted by the popularity of social governance,the input of the idea of diversified solutions and the pragmatic impetus under the pressure of social transformation.The mediation movement has the characteristics of both consciousness of pragmatism and the initial legalization,but will also face the mediation disorder.The remodeling of mediation must be rooted in systematization and modernization.Its development trend includes expansion of fields,symbiosis of autonomy and specialization,and mandatory introduction.展开更多
基金Supported by the Jiangsu Higher School Undergraduate Innovation and Entrepreneurship Training Program(202311117078Y)。
文摘In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation for the KdV equation to such coupled KdV system.Then from a trivial seed solution,we construct soliton solutions.We also give a nonlinear superposition formula,which allows us to generate multi-soliton solutions.
基金Project(202203021221138)supported by the Collaborative Innovation Center for Shanxi Advanced Permanent Materials and Technologythe 1331 Engineering of Shanxi ProvinceFundamental Research Program of Shanxi Province,China。
文摘Al-doped manganese dioxide(MnO_(2))was synthesized by simple hydrothermal method,and a controllable phase transition of the MnO_(2)crystal phase fromβtoδwas achieved.The effects of Al doping concentration on the structure and electrochemical properties of electrode materials were studied in detail.The results show that the controlled synthesis requires a synergy between KMnO_(4),MnCl_(2)and AlCl_(3),and that Al^(3+)plays an important role.Compared with the pure phase MnO_(2),the crystallinity of Al-doped MnO_(2)decreases and the specific surface area increases,which provides more active sites for the electrode material.When 3 mmol Al^(3+)is added,the prepared MnO_(2)-3 has the largest specific capacitance and the highest rate performance.The energy density of the asymmetric supercapacitor(ASC)with MnO_(2)-3 as the positive electrode and activated carbon(AC)as the negative electrode can reach 18.4 W·h/kg at the power density of 400 W/kg,and the capacity can maintain 90%of the initial value after 20000 cycles,indicating that Al-doped MnO_(2)has certain practical application value.This study provides favorable guidance for MnO_(2)as a high performance electrode material.
基金Projects(U24B20113,42477162) supported by the National Natural Science Foundation of ChinaProject(2025C02228) supported by the Primary Research and Development Plan of Zhejiang Province,China。
文摘Heat transfers at the interface of adjacent saturated soil primarily through the soil particles and the water in the voids.The presence of water induces the contraction of heat flow lines at the interface,leading to the emergence of the thermal contact resistance effect.In this paper,four thermal contact models were developed to predict the thermal contact resistance at the interface of multilayered saturated soils.Based on the theory of thermal-hydro-mechanical coupling,semi-analytical solutions of thermal consolidation subjected to time-dependent heating and loading were obtained by employing Laplace transform and its inverse transformation.Thermal consolidation characteristics of multilayered saturated soils under four different thermal contact models were discussed,and the effects of thermal resistance coefficient,partition thermal contact coefficient,and temperature amplitude on the thermal consolidation process were investigated.The outcomes indicate that the general thermal contact model results in the most pronounced thermal gradient at the interface,which can be degenerated to the other three thermal contact models.The perfect thermal contact model overestimates the deformation of the saturated soil during the thermal consolidation.Moreover,the effect of temperature on consolidation properties decreases gradually with increasing interfacial contact thermal resistance.
文摘The development and wide application of genetic transformation for cotton improvement are restrained by the unresolved problem of genotype dependence in regeneration in vitro.High embryogenic and regenerative potential have been obtained for limited number of Coker type genotypes。
文摘Judicial procedure,as a legal method to exercise the jurisdiction,has become an important element of the legal system construction.To improve the judicial procedure,legal procedure must be strictly complied with to complete the proceedings and the legitimate interests of the entities of the parties concerned and participants must be respected and protected.The reform of the judicial procedure system shall be strictly promoted and orderly carried out through scientific and reasonable setting,positive guidance in equal participation of both parties of the proceedings while making use of the security mechanism of supervision and restriction.
文摘"Law and literature " comes from an American radical law school of the1970 s,and it was then considered a campaign,thus the school became one of the most post-modernistic schools of thought. Due to its western theoretic background,it is necessary to interpret its context; in other words,the "Law and literature"problems shall be interpreted in the Chinese context,which can also provide much inspiration and reference for the construction of China's legal system.
基金the project of the Open Research Fund Program of Science and Technology on Aerospace Chemical Power Laboratory(Grant No.STACPL320221B04)Key Laboratory of Explosion Science and Technology(Beijing Institute of Technology)The project number is ZDKT21-01.
文摘The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical materials.However,the impact of the above coupling on thermal hazard assessment is not considered in the literature studies.In this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical materials.The linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal analyser.The thermal decomposition curves are decoupled by advanced thermokinetics software.The thermal decomposition and kinetic parameters before and after decoupling are calculated.The results of TG experiment show that both NQ and RDX began to lose mass during the endothermic stage.The endothermic melting and exothermic decomposition of NQ and RDX are coupled within this stage.The coupling effect has different degrees of influence on its initial decomposition temperature and safety parameters.Compared with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling decrease.The self-accelerating decomposition temperature increases,and internal thermal runaway time decreases.In the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。
基金Supported by the National Natural Science Foundation of China(12301101)the Guangdong Basic and Applied Basic Research Foundation(2022A1515110019 and 2020A1515110585)。
文摘In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequence of L^(1)functions converging to the given function and verifying their representation in the form of Fourier transform to establish the desired result of the given function.Applying this main result,we further generalize the Paley-Wiener theorem for band-limited functions to the analytic function spaces L^(p)(0<p<∞)with general weights.
文摘The room temperature phase diagram of Al-Zn-Cu system is the important basis for judging the phase constituents of the materials at the usage condition. New results about the room temperature phase diagram of the low copper side in the Al-Zn-Cu systems have been shown in this study. Miscibility gap of fcc phase in the Al-Zn-Cu system has also been studied by experimental diffusion-couple method and thermodynamic calculation. Properties of this miscibility gap have been known. It is practically significant for the study on the aging behavior and for the control of the microstructure and properties of the Al alloys with Zn and Cu element.
基金Project(51901248)supported by the National Natural Science Foundation of ChinaProject(2023JJ40742)supported by the Natural Science Foundation of Hunan Province,China。
文摘In the present study,molecular dynamic simulation(MD)was used to investigate the plastic deformation process of the Fe-Mn alloys with different Mn contents.The influences of Mn contents ranging from 10%to 30%(at%)on the deformation behavior and the controlling mechanism of the Fe-base alloys were analyzed.The results show that phase transformations and{112}<111>_(BCC)deformation twinning occur in all Fe-Mn alloys but follow different deformation paths.In the Fe-10%Mn alloy the deformation twinning mechanism obeys the FCC-related path,the Fe-20%Mn alloy involves both the FCC-and HCP-related paths,and the deformation of the Fe-30%Mn alloy is dominated by the HCP-related twinning path.The addition of Mn can increase the stacking fault energy and retard the activation of slip systems as well as the formation of stacking faults.Thus,a higher content of Mn can delay the FCC®ε-martensite and the subsequentε-martensite®BCC phase transition at the intersection of twoε-martensitic bands.Therefore,the addition of Mn alloying element increases the yield strength and reduces the elastic modulus of the Fe-Mn alloys.The formation of deformation twins will contribute to the work-hardening effect and delay the necking and fracture of alloys.It is expected that the results in the present study will provide theoretical reference for the design and optimization of high-performance steels.
基金Fifth Electronic Research Institute of the Ministry of Industry and Information Technology(HK07202200877)Pre-research Project on Civil Aerospace Technologies of CNSA(D020101)+2 种基金Zhejiang Provincial Science and Technology Plan Project(2022C01052)Frontier Scientific Research Program of Deep Space Exploration Laboratory(2022-QYKYJHHXYF-018,2022-QYKYJH-GCXD-001)Zhiyuan Laboratory(ZYL2024001)。
文摘Model-based system-of-systems(SOS)engineering(MBSoSE)is becoming a promising solution for the design of SoS with increasing complexity.However,bridging the models from the design phase to the simulation phase poses significant challenges and requires an integrated approach.In this study,a unified requirement modeling approach is proposed based on unified architecture framework(UAF).Theoretical models are proposed which compose formalized descriptions from both topdown and bottom-up perspectives.Based on the description,the UAF profile is proposed to represent the SoS mission and constituent systems(CS)goal.Moreover,the agent-based simulation information is also described based on the overview,design concepts,and details(ODD)protocol as the complement part of the SoS profile,which can be transformed into different simulation platforms based on the eXtensible markup language(XML)technology and model-to-text method.In this way,the design of the SoS is simulated automatically in the early design stage.Finally,the method is implemented and an example is given to illustrate the whole process.
基金Projects(42477162,52108347,52178371,52168046,52178321,52308383)supported by the National Natural Science Foundation of ChinaProjects(2023C03143,2022C01099,2024C01219,2022C03151)supported by the Zhejiang Key Research and Development Plan,China+6 种基金Project(LQ22E080010)supported by the Exploring Youth Project of Zhejiang Natural Science Foundation,ChinaProject(LR21E080005)supported by the Outstanding Youth Project of Natural Science Foundation of Zhejiang Province,ChinaProject(2022M712964)supported by the Postdoctoral Science Foundation of ChinaProject(2023AFB008)supported by the Natural Science Foundation of Hubei Province for Youth,ChinaProject(202203)supported by Engineering Research Centre of Rock-Soil Drilling&Excavation and Protection,Ministry of Education,ChinaProject(202305-2)supported by the Science and Technology Project of Zhejiang Provincial Communication Department,ChinaProject(2021K256)supported by the Construction Research Founds of Department of Housing and Urban-Rural Development of Zhejiang Province,China。
文摘This study proposes a general imperfect thermal contact model to predict the thermal contact resistance at the interface among multi-layered composite structures.Based on the Green-Lindsay(GL)thermoelastic theory,semi analytical solutions of temperature increment and displacement of multi-layered composite structures are obtained by using the Laplace transform method,upon which the effects of thermal resistance coefficient,partition coefficient,thermal conductivity ratio and heat capacity ratio on the responses are studied.The results show that the generalized imperfect thermal contact model can realistically describe the imperfect thermal contact problem.Accordingly,it may degenerate into other thermal contact models by adjusting the thermal resistance coefficient and partition coefficient.
基金funded by the Defence Science Technology Group(DSTG)。
文摘The Marplex Convention was established to prevent the manufacture of unmarked plastic explosives and stipulates that a volatile detection agent must be added at the time of manufacture.However,to-date,laboratory testing remains the internationally accepted practice for identifying and quantifying the taggants stipulated in the Convention.In this project,portable FTIR and Raman instruments were tested for their ability to detect 2,3-dimethyl-2,3-dinitrobutane(DMDNB),the chemical marker incorporated in plastic explosives that are manufactured within Australia.While both FTIR and Raman instruments detected solid DMDNB(98%purity),field analysis of plastic explosives at an Australian Defence establishment showed that both FTIR and Raman spectra were matched the relevant explosive(RDX or PETN),rather than the DMDNB taggant.For all three plastic explosives tested,the concentration of DMDNB was measured by SPME-GC-MS to be between 1.8 and 2%,greater than the minimum 1%concentration stipulated by the Marplex Convention.Additional testing with a plastic explosive analogue confirmed that the minor absorption peaks that would characterize low concentrations of DMDNB were masked by absorption bands from other compounds within the solid.Thus,while both FTIR and Raman spectroscopy are suitable for detection of plastic explosives,neither rely on the presence of DMDNB for detection.It is likely that similar results would be found for other taggants stipulated by the Marplex Convention,given they are also present in concentrations less than 1%.
文摘Martensitic transformation behavior was studied for zirconia containing 4%~10% CeO2 (in mole fraction) by using a dilatometric method. The Ms (Martensite start temperature) decreased near linearly with increasing CeO2. Different transformation modes were observed depending on the composition and cooling rate. ZrO2 containing 6% CeO2 showed isothermal transformation behavior, whereas ZrO2 containing 9% and 10% CeO2 showed athermal transformation behavior. However, ZrO2 containing 8% CeO2 showed either isothermal or athermal transformations behavior depending on the cooling rate. A TTT (Time-Temperature-Transformation) diagram was proposed for ZrO2 containing 8% CeO2.
文摘Based on current theories of diffusion and creep cavity closure at high temperature, a theoretical analysis of phase transformation diffusion bonding for T8/T8 eutectoid steel is carried out. The diffusion bonding is mainly described as two-stage process: Ⅰ The interfacial cavity with shape change from diamond to cylinder.Ⅱ The radius of the cylindrical cavity are reduced and eliminated gradually. A new theoretical model is established for the process of transformation superplastic diffusion bonding (TSDB) on the basis of a theoretical model for isothermal superplastic diffusion. The model can predict the bonding quality which is affected by technological parameters, such as limit cycling temperature, the compressive stress, the numbers of thermal cycles and temperature cycling through the phase transformation in the thermal cycling and so on. Results show that the maximum temperature, the compressive stress, the numbers of thermal cycles and the rate of temperature changing speed in the thermal cycling have an important influence on TSDB process. Meanwhile, reasonable technological parameters chosen from theoretical analysis is in good agreement with those obtained from experimental results.
文摘This paper proposes an efficient scheme to reduce the pre-correlation bandwidth effect in the global navigation satellite system(GNSS)receiver filtering process.It is mainly based on the application of a spectral transformation to the satellite-emitted signal that effectively reduces its band.At the receiver's end,this operation causes the spreading of noise over a much wider band than that used by the radio frequency stage.Consequently,the resulting auto-correlation function in the acquisition process acquires properties that enhance considerably the performance of the receiver in the presence of the multipath and noise disturbing phenomena.The simulation results demonstrate that the proposed method is a plausible solution for both multipath and noise problems in the GNSS applications for any limited value of the pre-correlation bandwidth in the receiver filter.
基金Project(50974140) supported by the National Natural Science Foundation of ChinaProject(VR-09157) supported by Beijing Synchrotron Radiation Facility (BSRF) Public User Program,China
文摘Sulfur speciation transformation during bioleaching of pyrite-containing sphalerite concentrate by thermophile Sulfolobus metallicus (S. metallicus) at 65 ℃ was investigated by X-ray diffraction (XRD), diffuse reflectance Fourier transform infrared spectroscopy (FT-IR) and sulfur K-edge X-ray absorption near edge structure spectroscopy (XANES). The results show that the presence of S. metallicus effectively enhances the dissolution of the mineral. The yield of zinc increases from 0.5 g/L in sterile control to 2.7 g/L in bioleaching. The pyrite in the concentrate facilitates zinc dissolution in the early stage, but has hindrance role in the late stage for the formation of jarosite. Sulfur speciation analyses show that jarosite and elemental sulfur are main products in bioleaching process, and the accumulation ofjarosite is mainly responsible for the decline of leaching efficiency.
基金No any funds were received from any agency for this study.
文摘Since the advent of transgenic technology,the incorporation of gene(s)encoding traits of economic importance in cotton is being practiced worldwide.However,factors like recalcitrant nature of cotton cultivars,in vitro regeneration via tissue culture(especially via somatic embryogenesis),genotype dependency,long and toilsome protocols impede the pace of development of transgenic cotton.Besides that,types and age of explants,media composition,plant growth regulators and other environmental factors affect in vitro cotton regeneration significantly.The studies of genetic control of in vitro regeneration in plants have elucidated the role of certain transcription factor genes that are induced and expressed during somatic embryogenesis.Among these transcription factors,BABY BOOM(BBM)plays a very important role in signal transduction pathway,leading to cell differentiation and somatic embryos formation.The role of BBM has been established in plant cell proliferation,growth and development even without exogenous growth regulators.This review intends to provide an informative summary of regeneration and transformation problems in cotton and the latest developments in utilization of BBM transcription factors in cotton.We believe that the use of BBM will not only ease cotton genetic improvement but will also accelerate cotton breeding programmes.
基金A phasic achievement of the Ministry of Education Youth Fund Project named “Law Research on Online Transaction of Rural Land Management Right under the Background of Rural Revitalization Strategy”(Project No.18yjc820001)funded by the China Scholarship Council(Project No.201907845009)
文摘Financing difficulties have always been one of the bottlenecks restricting the development of"three rural".The core to solve the difficulties is to seek financing collaterals that in line with the law and with the value able to be effectively evaluated.Besides,the law confirmation of the mortgage financing's form for Rural Land ManagementRight(RLMR)is the primary prerequisite for rural land financing.With the continuous advancement of rural revitalization strategy,the rural land reform with the main content of"three powers separation"has paid more attention to the functions of RLMR financing.Due to the lack of supply of existing laws,there are still certain legal risks in the financing of RLMR.Based on rural revitalization strategy,this paper made an in-depth analysis of the causes of financing risk of RLMR.Furthermore,we put forward some possible paths to legalize this right.
文摘Under the dual driven forces of soaring disputes and national policy,the dispute resolution ecosystem of China showed the mediation centralism,and the revival of mediation presented the characteristics of adversary system.In order to comply with the modern rule of law system,the traditional mediation is incorporated into the modern legal system through the three-level transformation of"discipline of laws","introduction of procedures"and"specialized cultivation",which was promoted by the popularity of social governance,the input of the idea of diversified solutions and the pragmatic impetus under the pressure of social transformation.The mediation movement has the characteristics of both consciousness of pragmatism and the initial legalization,but will also face the mediation disorder.The remodeling of mediation must be rooted in systematization and modernization.Its development trend includes expansion of fields,symbiosis of autonomy and specialization,and mandatory introduction.