Fused deposition molding is an advanced kind of rapid prototyping technology. On the accuracy of the forming process, the research on the temperature of the molding material is based on the analysis of the forming par...Fused deposition molding is an advanced kind of rapid prototyping technology. On the accuracy of the forming process, the research on the temperature of the molding material is based on the analysis of the forming parameters. The influence of the tenlperature of the molding material on the specimen is reasonably described by the actual forming part and the finite element analysis model. The experimental results show that the temperatur( of the molding material is less affected by the temperature of the molding material in a certain range. This will lay the theoretical foundation for the formation of the molding technology in the future展开更多
A temperature stable Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1)ceramics were fabricated using a conventional solid-state route sintered at 1100℃for 4 h.The XRD results indicate that the main phase Li2ZnTi3O8 and secondary...A temperature stable Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1)ceramics were fabricated using a conventional solid-state route sintered at 1100℃for 4 h.The XRD results indicate that the main phase Li2ZnTi3O8 and secondary phase including SrxCa1-xTiO3(0≤x≤1)solid solution and TiO2 co-exist in composite and form a stable composite system when the(CaxSr1-x)(0≤x≤1)substitutes for Zn of Li2ZnTi3O8 ceramic.As x is increased from 0 to 1,the relative permittivity(εr)increases from 26.65 to 27.12,and the quality factor(Q×f)increases from 63300 to 66600 GHz.With the increased of x,the temperature coefficient of resonant frequency(τf)increases from 0.27 to 8.23 ppm/℃,and then decreases to 3.51 ppm/℃.On the whole,the Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1)ceramics show excellent comprehensive properties of middleεr=25-27,higher Q×f≥60000 GHz andτf≤±8.5 ppm/℃.展开更多
In the past half century China has developed and formed her own system ofhigh temperature materials for power, automobile and aero-engine industries in the temperature rangefrom 550 deg C to 1100 deg C. These high tem...In the past half century China has developed and formed her own system ofhigh temperature materials for power, automobile and aero-engine industries in the temperature rangefrom 550 deg C to 1100 deg C. These high temperature materials include heat-resisting steels,iron-base, nickel-iron-base and nickel-base superalloys. Some achievements - in high temperaturestrength study, new technologies and new alloy development are also discussed.展开更多
Carbon fiber reinforced phenolic based composites were prepared by laminating molding. The variation in mechanical characteristics of composites was evaluated with heating temperature and procedure. The microstructure...Carbon fiber reinforced phenolic based composites were prepared by laminating molding. The variation in mechanical characteristics of composites was evaluated with heating temperature and procedure. The microstructures of composites at different temperatures were observed by optical microscope and scanning electron microscope, respectively. The results showed that the main weight loss range of carbon/phenolic is from 300 to 800 ℃, before 700 ℃ the weight loss was resulted from pyrolysis and after that the weight loss was mainly by oxidation in the fiber phase; with the heat treatment temperature rising, the bonding at the interface of carbon fibers and resin matrix weakened; in the pyrolysis temperature range, the interlaminar shear strength(ILSS) of carbon/phenolic showed a rapid drop with temperature rising, and then decrease in the rate of ILSS became relatively slower; the fiber oxidation had little influence on the ILSS.展开更多
Improved life assessment techniques will enable engineering components to be replaced before failure, thereby reducing the risk of industrial accidents as well as minimizing financial loss due to unscheduled outages. ...Improved life assessment techniques will enable engineering components to be replaced before failure, thereby reducing the risk of industrial accidents as well as minimizing financial loss due to unscheduled outages. For components operating at high temperatures, temperature measurement is very important. In many situations, the environmental conditions are too hostile for conventional techniques to be used. Researchers over the world have been looking for new techniques for temperature measurement and one such device, called Feroplug, has been developed previously by the and coworkers. The Feroplug has been patented in USA, UK and Europe by the British Technology Group. The underlying principle of the Feroplug is based on the transformation of ferrite in some specially designed duplex stainless steels. This paper describes a new invention called Sigmaplug which is a new development of the Feroplug but using an entirely different physical principle. It was discovered that the sigma phase in Fe展开更多
The practical condition of needle-punched filters applied in coal-fired power plants is investigated. According to the actual operating conditions, two common filters (glass fiber filter and polyphenylene sulfide (PPS...The practical condition of needle-punched filters applied in coal-fired power plants is investigated. According to the actual operating conditions, two common filters (glass fiber filter and polyphenylene sulfide (PPS) filter) are selected for experiment. The performance of these two kinds of filter is compared based on a series of tests such as resistance to the acid and alkali, oxidation resistance,hydrolysis resistance,and wear resistance. Experimental results show that PPS filter materials have better properties than those of glass filter material except oxidation resistance. Composite filter mixed glass fiber and PPS is recommended for polluters because of its good properties in all aspects.展开更多
LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode material is prepared by sol-gel method and the effects of Nb^(5+)doping and different calcination temperatures on cathode materials were deeply investigated.Structural and morpho...LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode material is prepared by sol-gel method and the effects of Nb^(5+)doping and different calcination temperatures on cathode materials were deeply investigated.Structural and morphological characterizations revealed that the optimal content of 1 mol%Nb^(5+)can stabilize layered structures,mitigate Ni^(2+)migration to Li layers,improve lithium diffusion capacity,and reduce lattice expansion/shrinkage while cycling.And calcination temperature at 800℃can not only ensure good morphology,but also suppress the mixed discharge of lithium and nickel in the internal structure.Electrochemical performance evaluation revealed that Nb^(5+)doping improves the discharge-specific capacity of the material,which is conducive to ameliorating its rate capability and cycle performance.And the material at 800℃exhibits the highest discharge specific capacity,the best magnification performance,low polarizability,and the best cycle reversibility.展开更多
This paper briefiy introduces the R&D of intermetallics in China. R&D on intermetallics in a national scale in China began near ten years ago. The investigation in past years focused on the fundamental researc...This paper briefiy introduces the R&D of intermetallics in China. R&D on intermetallics in a national scale in China began near ten years ago. The investigation in past years focused on the fundamental research and materials development. A significant progress has been made. Various components that made of Ti3Al Ni3Al, TiAl and Fe3Al have been successfully manufactured Some of them have been evaluted. It is expected that some intermetallic alloys will be produced in an industrial scale in the near future.展开更多
In order to promote the application of clean energy technology in clothing and promote the integration of industrial development and artificial intelligence wearable technology,this study elaborates the energy applica...In order to promote the application of clean energy technology in clothing and promote the integration of industrial development and artificial intelligence wearable technology,this study elaborates the energy application characteristics of intelligent wearable products at home and abroad and its application in different fields,aiming at the current research status of wearable technology in the field of textile and clothing.The wearable distributed generation technology is classified,and a creative clothing design for detecting climate temperature is designed.Based on the monitoring of body temperature,the changes in clothing pattern color can reflect people’s health and emotional status.At the same time,it can also be applied to the screening of abnormal body temperature during the COVID-19.展开更多
Low temperature calorimetry is an experimental method of heat capacity measurements, and heatcapacity is one of the most important and fundamental thermodynamic properties of substances. Theheat capacity can provide a...Low temperature calorimetry is an experimental method of heat capacity measurements, and heatcapacity is one of the most important and fundamental thermodynamic properties of substances. Theheat capacity can provide an average evaluation of the thermal property of a sample since it is a bull(property of substances. In the other hand, the condensed states of substances could be mainly controlledby the molecular motions, intermolecular interactions, and interplay among molecular structures. Thephysical property reflected in a material may be closely related to the energy changes in these threefactors, which can be directly observed in a heat capacity curve. Therefore, low temperature calorimetryhas been used not only to obtain heat capacity, entropy, enthalpy and Gibbs free energy, but also toinvestigate and understand lattice vibrations, metals, superconductivity, electronic and nuclearmagnetism, dilute magnetic systems and structural transitions. In this review, we have presented theconcept of low temperature calorimetry and its applications in the related field of material researches,such as nano-materials, magnetic materials, ferroelectric materials, phase change materials and othermaterials.展开更多
Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temp...Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temperature(LCST) is often sharp, which allows for a wide range of smart material applications.At the LCST, oligo(ethylene glycol)-substituted polyisocyanides(PICs) form soft hydrogels, composed of polymer bundles similar to biological gels, such as actin, fibrin and intermediate filaments. Here, we show that the LCST of PICs strongly depends linearly on the length of the ethylene glycol(EG) tails; every EG group increases the LCSTand thus the gelation temperature by nearly 30 ℃. Using a copolymerisation approach, we demonstrate that we can precisely tailor the gelation temperature between 10 ℃ and 60 ℃and, consequently, tune the mechanical properties of the PIC gels.展开更多
Boron subphosphide(B_(12)P_(2))is a promising high temperature thermoelectric material due to its good thermal stability,and chemical inertness.However,the thermal properties of B_(12)P_(2) have not been well revealed...Boron subphosphide(B_(12)P_(2))is a promising high temperature thermoelectric material due to its good thermal stability,and chemical inertness.However,the thermal properties of B_(12)P_(2) have not been well revealed so far.Here,we first develop a deep learning potential for B_(12)P_(2) based on quantum mechanical calculations.Then the isotropic lattice thermal conductivity(LTC)of crystalline B_(12)P_(2) is predicted to be 39.70±4.38 W/m⋅K from molecular dynamics simulations using this deep learning potential.The LTC exhibits the relationship ofκL~1/T in the temperature range of 300~1500 K.More important,a twin boundary strategy is proposed to reduce the LTC of B_(12)P_(2).In nanotwinned B_(12)P_(2),the phonon transport in all directions is significantly suppressed by twin boundaries(TBs)with the isotropic LTC of 15.85±2.70 W/m⋅K,especially in the direction normal to the TB plane.The decrease of vibrational density of states and phonon participation ratio due to TBs’phonon scattering is the main reason of the low LTC in nanotwinned B_(12)P_(2).In addition,the elastic moduli(B and G)of B_(12)P_(2) crystal decrease by less than 7%after inducing TBs,which suggests that the mechanical properties are not significantly affected by TBs.Overall,this work enriches our understanding of the thermal properties of B_(12)P_(2) and offers a promising approach,i.e.,introducing TBs,to design high-performance thermoelectric materials.展开更多
文摘Fused deposition molding is an advanced kind of rapid prototyping technology. On the accuracy of the forming process, the research on the temperature of the molding material is based on the analysis of the forming parameters. The influence of the tenlperature of the molding material on the specimen is reasonably described by the actual forming part and the finite element analysis model. The experimental results show that the temperatur( of the molding material is less affected by the temperature of the molding material in a certain range. This will lay the theoretical foundation for the formation of the molding technology in the future
基金Funded by the Open Project Program of Key Laboratory of Inorganic Functional Materials and Devices,Chinese Academy of Sciences(No.KLIFMD201606)the Open Fund of National Innovation Platform(No.2017YJ163)+1 种基金the National Natural Science Foundation of China(Nos.51502220,51521001,and 51672197)the Open Foundation of Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics(Wuhan University of Technology)(No.TAM201802)。
文摘A temperature stable Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1)ceramics were fabricated using a conventional solid-state route sintered at 1100℃for 4 h.The XRD results indicate that the main phase Li2ZnTi3O8 and secondary phase including SrxCa1-xTiO3(0≤x≤1)solid solution and TiO2 co-exist in composite and form a stable composite system when the(CaxSr1-x)(0≤x≤1)substitutes for Zn of Li2ZnTi3O8 ceramic.As x is increased from 0 to 1,the relative permittivity(εr)increases from 26.65 to 27.12,and the quality factor(Q×f)increases from 63300 to 66600 GHz.With the increased of x,the temperature coefficient of resonant frequency(τf)increases from 0.27 to 8.23 ppm/℃,and then decreases to 3.51 ppm/℃.On the whole,the Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1)ceramics show excellent comprehensive properties of middleεr=25-27,higher Q×f≥60000 GHz andτf≤±8.5 ppm/℃.
文摘In the past half century China has developed and formed her own system ofhigh temperature materials for power, automobile and aero-engine industries in the temperature rangefrom 550 deg C to 1100 deg C. These high temperature materials include heat-resisting steels,iron-base, nickel-iron-base and nickel-base superalloys. Some achievements - in high temperaturestrength study, new technologies and new alloy development are also discussed.
基金the Innovation Foundation of Postgraduate of Jiangsu Province,China(No.CX08B_134Z)Beforehand Research Fund of Defense Technology(No.404040301)The Fundamental Research Funds for the Central Universities(No.NUST2011XQTR13)
文摘Carbon fiber reinforced phenolic based composites were prepared by laminating molding. The variation in mechanical characteristics of composites was evaluated with heating temperature and procedure. The microstructures of composites at different temperatures were observed by optical microscope and scanning electron microscope, respectively. The results showed that the main weight loss range of carbon/phenolic is from 300 to 800 ℃, before 700 ℃ the weight loss was resulted from pyrolysis and after that the weight loss was mainly by oxidation in the fiber phase; with the heat treatment temperature rising, the bonding at the interface of carbon fibers and resin matrix weakened; in the pyrolysis temperature range, the interlaminar shear strength(ILSS) of carbon/phenolic showed a rapid drop with temperature rising, and then decrease in the rate of ILSS became relatively slower; the fiber oxidation had little influence on the ILSS.
文摘Improved life assessment techniques will enable engineering components to be replaced before failure, thereby reducing the risk of industrial accidents as well as minimizing financial loss due to unscheduled outages. For components operating at high temperatures, temperature measurement is very important. In many situations, the environmental conditions are too hostile for conventional techniques to be used. Researchers over the world have been looking for new techniques for temperature measurement and one such device, called Feroplug, has been developed previously by the and coworkers. The Feroplug has been patented in USA, UK and Europe by the British Technology Group. The underlying principle of the Feroplug is based on the transformation of ferrite in some specially designed duplex stainless steels. This paper describes a new invention called Sigmaplug which is a new development of the Feroplug but using an entirely different physical principle. It was discovered that the sigma phase in Fe
文摘The practical condition of needle-punched filters applied in coal-fired power plants is investigated. According to the actual operating conditions, two common filters (glass fiber filter and polyphenylene sulfide (PPS) filter) are selected for experiment. The performance of these two kinds of filter is compared based on a series of tests such as resistance to the acid and alkali, oxidation resistance,hydrolysis resistance,and wear resistance. Experimental results show that PPS filter materials have better properties than those of glass filter material except oxidation resistance. Composite filter mixed glass fiber and PPS is recommended for polluters because of its good properties in all aspects.
文摘LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode material is prepared by sol-gel method and the effects of Nb^(5+)doping and different calcination temperatures on cathode materials were deeply investigated.Structural and morphological characterizations revealed that the optimal content of 1 mol%Nb^(5+)can stabilize layered structures,mitigate Ni^(2+)migration to Li layers,improve lithium diffusion capacity,and reduce lattice expansion/shrinkage while cycling.And calcination temperature at 800℃can not only ensure good morphology,but also suppress the mixed discharge of lithium and nickel in the internal structure.Electrochemical performance evaluation revealed that Nb^(5+)doping improves the discharge-specific capacity of the material,which is conducive to ameliorating its rate capability and cycle performance.And the material at 800℃exhibits the highest discharge specific capacity,the best magnification performance,low polarizability,and the best cycle reversibility.
文摘This paper briefiy introduces the R&D of intermetallics in China. R&D on intermetallics in a national scale in China began near ten years ago. The investigation in past years focused on the fundamental research and materials development. A significant progress has been made. Various components that made of Ti3Al Ni3Al, TiAl and Fe3Al have been successfully manufactured Some of them have been evaluted. It is expected that some intermetallic alloys will be produced in an industrial scale in the near future.
文摘In order to promote the application of clean energy technology in clothing and promote the integration of industrial development and artificial intelligence wearable technology,this study elaborates the energy application characteristics of intelligent wearable products at home and abroad and its application in different fields,aiming at the current research status of wearable technology in the field of textile and clothing.The wearable distributed generation technology is classified,and a creative clothing design for detecting climate temperature is designed.Based on the monitoring of body temperature,the changes in clothing pattern color can reflect people’s health and emotional status.At the same time,it can also be applied to the screening of abnormal body temperature during the COVID-19.
基金financially supported by the National Natural Science Foundation of China(Nos.21473198,11775226)Natural Science Foundation of Liaoning Provincial(No.201602741)Hundred-Talent Program founded by Chinese Academy of Sciences
文摘Low temperature calorimetry is an experimental method of heat capacity measurements, and heatcapacity is one of the most important and fundamental thermodynamic properties of substances. Theheat capacity can provide an average evaluation of the thermal property of a sample since it is a bull(property of substances. In the other hand, the condensed states of substances could be mainly controlledby the molecular motions, intermolecular interactions, and interplay among molecular structures. Thephysical property reflected in a material may be closely related to the energy changes in these threefactors, which can be directly observed in a heat capacity curve. Therefore, low temperature calorimetryhas been used not only to obtain heat capacity, entropy, enthalpy and Gibbs free energy, but also toinvestigate and understand lattice vibrations, metals, superconductivity, electronic and nuclearmagnetism, dilute magnetic systems and structural transitions. In this review, we have presented theconcept of low temperature calorimetry and its applications in the related field of material researches,such as nano-materials, magnetic materials, ferroelectric materials, phase change materials and othermaterials.
基金the Netherlands Organisation for Scientific Research (NWO)for providing and supporting beam time at the DutchBelgium beamline(DUBBLE) for SAXS experiments(No. BM26-02773)financial support from NWO (VENI grant No. 680-47-437)+2 种基金the Euopean Union's 2020 ResearchInnovation Programme under Grant Agreement No. 642687project Biogel
文摘Thermosensitive polymers show an entropy-driven transition from a well-solvated to a poorly solvated polymer chain, resulting in a more compact globular conformation. The transition at the lower critical solution temperature(LCST) is often sharp, which allows for a wide range of smart material applications.At the LCST, oligo(ethylene glycol)-substituted polyisocyanides(PICs) form soft hydrogels, composed of polymer bundles similar to biological gels, such as actin, fibrin and intermediate filaments. Here, we show that the LCST of PICs strongly depends linearly on the length of the ethylene glycol(EG) tails; every EG group increases the LCSTand thus the gelation temperature by nearly 30 ℃. Using a copolymerisation approach, we demonstrate that we can precisely tailor the gelation temperature between 10 ℃ and 60 ℃and, consequently, tune the mechanical properties of the PIC gels.
文摘Boron subphosphide(B_(12)P_(2))is a promising high temperature thermoelectric material due to its good thermal stability,and chemical inertness.However,the thermal properties of B_(12)P_(2) have not been well revealed so far.Here,we first develop a deep learning potential for B_(12)P_(2) based on quantum mechanical calculations.Then the isotropic lattice thermal conductivity(LTC)of crystalline B_(12)P_(2) is predicted to be 39.70±4.38 W/m⋅K from molecular dynamics simulations using this deep learning potential.The LTC exhibits the relationship ofκL~1/T in the temperature range of 300~1500 K.More important,a twin boundary strategy is proposed to reduce the LTC of B_(12)P_(2).In nanotwinned B_(12)P_(2),the phonon transport in all directions is significantly suppressed by twin boundaries(TBs)with the isotropic LTC of 15.85±2.70 W/m⋅K,especially in the direction normal to the TB plane.The decrease of vibrational density of states and phonon participation ratio due to TBs’phonon scattering is the main reason of the low LTC in nanotwinned B_(12)P_(2).In addition,the elastic moduli(B and G)of B_(12)P_(2) crystal decrease by less than 7%after inducing TBs,which suggests that the mechanical properties are not significantly affected by TBs.Overall,this work enriches our understanding of the thermal properties of B_(12)P_(2) and offers a promising approach,i.e.,introducing TBs,to design high-performance thermoelectric materials.