BACKGROUND Polygoni Cuspidati Rhizoma et Radix(PCRR),a well-known traditional Chinese medicine(TCM),inhibits inflammation associated with various human diseases.However,the anti-inflammatory effects of PCRR in acute l...BACKGROUND Polygoni Cuspidati Rhizoma et Radix(PCRR),a well-known traditional Chinese medicine(TCM),inhibits inflammation associated with various human diseases.However,the anti-inflammatory effects of PCRR in acute lung injury(ALI)and the underlying mechanisms of action remain unclear.AIM To determine the ingredients related to PCRR for treatment of ALI using multiple databases to obtain potential targets for fishing.METHODS Recognized and candidate active compounds for PCRR were obtained from Traditional Chinese Medicine Systems Pharmacology,STITCH,and PubMed databases.Target ALI databases were built using the Therapeutic Target,DrugBank,DisGeNET,Online Mendelian Inheritance in Man,and Genetic Association databases.Network pharmacology includes network construction,target prediction,topological feature analysis,and enrichment analysis.Bioinformatics resources from the Database for Annotation,Visualization and Integrated Discovery were utilized for gene ontology biological process and Kyoto Encyclopedia of Genes and Genomes network pathway enrichment analysis,and molecular docking techniques were adopted to verify the combination of major active ingredients and core targets.RESULTS Thirteen bioactive compounds corresponding to the 433 PCRR targets were identified.In addition,128 genes were closely associated with ALI,60 of which overlapped with PCRR targets and were considered therapeutically relevant.Functional enrichment analysis suggested that PCRR exerted its pharmacological effects in ALI by modulating multiple pathways,including the cell cycle,cell apoptosis,drug metabolism,inflammation,and immune modulation.Molecular docking results revealed a strong associative relationship between the active ingredient and core target.CONCLUSION PCRR alleviates ALI symptoms via molecular mechanisms predicted by network pharmacology.This study proposes a strategy to elucidate the mechanisms of TCM at the network pharmacology level.展开更多
This paper reports the preparation of nano-TiO2 (about 10 nm) powder by the method of precipitation. In detail, some breparation conditions were investigated in order to find out how to control the grain size and redu...This paper reports the preparation of nano-TiO2 (about 10 nm) powder by the method of precipitation. In detail, some breparation conditions were investigated in order to find out how to control the grain size and reduce the agglomeration of powders. Also, the reflex spectra of nano-scale powders with different grain size were studied. It tvas found that the wave length and width of reflex spectra are connected with the grain size of nano-TiO2 powders展开更多
In order to investigate the burning characteristics of a 0#diesel and 3#jet fuel,a small-scale experimental bench mainly composed of a cone calorimeter was arranged.The heat release and burning rates were investigated...In order to investigate the burning characteristics of a 0#diesel and 3#jet fuel,a small-scale experimental bench mainly composed of a cone calorimeter was arranged.The heat release and burning rates were investigated changing the external irradiance in order to clarify the triadic relationship among these quantities.The effective heat of combustion of 0#diesel and 3#jet fuel were 38.89 MJ/kg and 43.15 MJ/kg,respectively,with the corresponding combustion efficiencies being 96.78%and 99.60%(the effective peak heat of combustion being 1.665 times the mean value for both types of fuel).According to our experimental results,the heat release rate and burning rate of 0#diesel and 3#jet fuel both grow linearly with an increase in the external irradiance.Moreover,the heat release rate and burning rate of 3#jet fuel are greater than the equivalent values for the 0#diesel.The average smoke production rate of 0#diesel grows with an increase in the external irradiance,while for the 3#jet fuel it remains approximately the same.The specific extinction area of these two kinds of fuel shows a subtle decrease with the increase of external irradiance.The time to ignition of 3#jet fuel is smaller than 0#diesel for all the considered external irradiances,which indicates that 3#jet fuel is easier to ignite than the 0#diesel.展开更多
The effects of gate oxide traps on gate leakage current and device performance of metal–oxide–nitride–oxide–silicon(MONOS)-structured NAND flash memory are investigated through Sentaurus TCAD. The trap-assisted tu...The effects of gate oxide traps on gate leakage current and device performance of metal–oxide–nitride–oxide–silicon(MONOS)-structured NAND flash memory are investigated through Sentaurus TCAD. The trap-assisted tunneling(TAT)model is implemented to simulate the leakage current of MONOS-structured memory cell. In this study, trap position, trap density, and trap energy are systematically analyzed for ascertaining their influences on gate leakage current, program/erase speed, and data retention properties. The results show that the traps in blocking layer significantly enhance the gate leakage current and also facilitates the cell program/erase. Trap density ~10^(18) cm^(-3) and trap energy ~ 1 eV in blocking layer can considerably improve cell program/erase speed without deteriorating data retention. The result conduces to understanding the role of gate oxide traps in cell degradation of MONOS-structured NAND flash memory.展开更多
The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00...The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00 and off at 18:00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00:00, 04:00, 08:00, 12:00, 16:00 and 20:00 with 60 turtles each (Initial body weight 88.27 - 0.09 g). Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate (SGR) and RNA/ DNA:SGR=t.1586RNA/DNA-0.7097 (r = 0.9328, P = 0.0066). The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12:00 were the lowest from the six groups (P 〈 0.05). Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight (FBW), higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total.展开更多
A recent novel coronavirus(COVID-19)outbreak has started since December 2019 in Wuhan,Hubei province,People’s Republic of China and has progressively expanded to various parts of China.Based on those practical proble...A recent novel coronavirus(COVID-19)outbreak has started since December 2019 in Wuhan,Hubei province,People’s Republic of China and has progressively expanded to various parts of China.Based on those practical problems of emergency science popularization works in the current epidemic situation,this article,from the perspective of accuracy,timeliness and acceptability of emergency science popularization,proposes that the professional science popularization knowledge should be popularized,rumor should be refuted in a timely manner,and accurate science popularization strategies should be taken for different science preference,so to provide countermeasures and guidance for problems in emergency science popularization.展开更多
To guarantee the blue skies for the 2022 Winter Olympics held in Beijing and Zhangjiakou from February 4 to 20,Beijing and its surrounding areas adopted a series of emission control measures.This provides an opportuni...To guarantee the blue skies for the 2022 Winter Olympics held in Beijing and Zhangjiakou from February 4 to 20,Beijing and its surrounding areas adopted a series of emission control measures.This provides an opportunity to determine the impacts of large-scale temporary control measures on the air quality in Beijing during this special period.Here,we applied the WRF-CMAQ model to quantify the contributions of emission reduction measures and meteorological conditions.Results show that meteorological conditions in 2022 decreased PM_(2.5)in Beijing by 6.9 and 11.8μg/m^(3)relative to 2021 under the scenarios with and without emission reductions,respectively.Strict emission reduction measures implemented in Beijing and seven neighboring provinces resulted in an average decrease of 13.0μg/m^(3)(-41.2%)in PM_(2.5)in Beijing.Over the entire period,local emission reductions contributed more to good air quality in Beijing than nonlocal emission reductions.Under the emission reduction scenario,local,controlled regions,other regions,and boundary conditions contributed 47.7%,42.0%,5.3%,and 5.0%to the PM_(2.5)concentrations in Beijing,respectively.The results indicate that during the cleaning period with the air masses from the northwest,the abatements of PM_(2.5)were mainly caused by local emission reductions.However,during the potential pollution period with the air masses from the east-northeast and west-southwest,the abatements of PM_(2.5)were caused by both local and nonlocal emission reductions almost equally.This implies that regional coordinated prevention and control strategies need to be arranged scientifically and rationally when heavy pollution events are forecasted.展开更多
The Aqishan-Yamansu metallogenic belt(AYMB)in East Tianshan hosts abundant sub-marine volcanic-hosted iron deposits.Although there is agreement with the magmatic source of the ore-forming materials and the role of hyd...The Aqishan-Yamansu metallogenic belt(AYMB)in East Tianshan hosts abundant sub-marine volcanic-hosted iron deposits.Although there is agreement with the magmatic source of the ore-forming materials and the role of hydrothermal replacement in iron ore formation,the mineraliza-tion processes of these iron deposits remain uncertain.Three ore types are identified on the basis of the geological occurrences of minerals and the sequence of mineral in ores.The typeⅠores are characte-rized by magnetite,diopside,amphibole with a few pyrite,and chalcopyrite.The type II ores are mainly composed of magnetite,garnet,chlorite with a few pyrite,while the type III ores are mainly composed of magnetite,quartz,calcite with a few pyrite.In order to constrain the mineralization processes of these ore types,we performed iron isotopes and trace element compositions of magnetite from three typical iron deposits(Yamansu,Duotoushan and Luotuofeng).Trace element and Fe isotope investiga-tions of the three ore types reveal two major groups.The groupⅠconsists of analyses of the typeⅠandⅡores,with both showing a narrow range of positiveδ56Fe values(+0.08‰to+0.22‰for typeⅠores and+0.15‰ to+0.22‰ for typeⅡores)and plotting in the range of the ortho-magmatic field.In contrast,the group 2 is composed merely of the typeⅢores,showing a wider range of negativeδ56Fe values(-0.49‰ to-0.01‰),which is similar to the features of Fe-skarn magnetite.As shown in the binary dia-grams of magnetite trace elements and a fractionation of the Fe isotopes,different ore types were likely produced during gradually changing ore-forming stages from magmatic to hydrothermal.Collectively,the submarine volcanic-hosted iron deposits in the East Tianshan are likely the results of a continuous magmatic-hydrothermal mineralization process.展开更多
The 5-methylcytosine DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)-mediated active DNA demethylation is critical for shaping the genomic DNA methylation landscape in Arabidopsis.Whether and how the stability of...The 5-methylcytosine DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)-mediated active DNA demethylation is critical for shaping the genomic DNA methylation landscape in Arabidopsis.Whether and how the stability of ROS1 may be regulated by post-translational modifications is unknown.Using a methylation-sensitive PCR(CHOP-PCR)-based forward genetic screen forArabidopsis DNA hyper-methyl-ation mutants,we identified the SUMO E3 ligase SIZ1 as a critical regulator of active DNA demethylation.Dysfunction of SIZ1 leads to hyper-methylation at approximately 1000 genomic regions.SIZ1 physically in-teracts with ROS1 and mediates the SUMOylation of ROS1.The SUMOylation of ROS1 is reduced in siz1 mutant plants.Compared with that in wild-type plants,the protein level of ROS1 is significantly decreased,whereas there is an increased level of ROS1 transcripts in siz1 mutant plants.Our results suggest that SIZ1-mediated SUMOylation of ROS1 promotes its stability and positively regulates active DNA demethylation.展开更多
In the current work,the bulk ternary(0.85-x)BiFeO3-xBaTiO3-0.15PbTiO3(BF-BTx-PT,x=0.08-0.35)system has been studied as a potential high-temperature piezoceramics.Samples with various content of BT were prepared via so...In the current work,the bulk ternary(0.85-x)BiFeO3-xBaTiO3-0.15PbTiO3(BF-BTx-PT,x=0.08-0.35)system has been studied as a potential high-temperature piezoceramics.Samples with various content of BT were prepared via solid-state route,and pure perovskite phase was confirmed by X-ray diffraction.The temperature dependence of dielectric constants confirmed the decrease of Curie temperature with increasing BT content.It was found that the morphotropic phase boundary(MPB)composition of BF-BTx-PT ceramics was in the vicinity of x=0.15,which exhibits optimal properties with piezoelectric constant d33 of 60 pC/N,high Curie temperature of 550℃,and low sintering temperature of 920℃.Measurements also showed that the depoling temperature was 300℃,about 150℃higher than that of commercialized PZT ceramics,which indicated good temperature stability.BF-BTx-PT ceramics are promising candidates for high temperature applications.展开更多
基金Supported by Shandong Province Integrated Traditional Chinese and Western Medicine Professional Disease Prevention and Control Project,No.YXH2019ZXY010.
文摘BACKGROUND Polygoni Cuspidati Rhizoma et Radix(PCRR),a well-known traditional Chinese medicine(TCM),inhibits inflammation associated with various human diseases.However,the anti-inflammatory effects of PCRR in acute lung injury(ALI)and the underlying mechanisms of action remain unclear.AIM To determine the ingredients related to PCRR for treatment of ALI using multiple databases to obtain potential targets for fishing.METHODS Recognized and candidate active compounds for PCRR were obtained from Traditional Chinese Medicine Systems Pharmacology,STITCH,and PubMed databases.Target ALI databases were built using the Therapeutic Target,DrugBank,DisGeNET,Online Mendelian Inheritance in Man,and Genetic Association databases.Network pharmacology includes network construction,target prediction,topological feature analysis,and enrichment analysis.Bioinformatics resources from the Database for Annotation,Visualization and Integrated Discovery were utilized for gene ontology biological process and Kyoto Encyclopedia of Genes and Genomes network pathway enrichment analysis,and molecular docking techniques were adopted to verify the combination of major active ingredients and core targets.RESULTS Thirteen bioactive compounds corresponding to the 433 PCRR targets were identified.In addition,128 genes were closely associated with ALI,60 of which overlapped with PCRR targets and were considered therapeutically relevant.Functional enrichment analysis suggested that PCRR exerted its pharmacological effects in ALI by modulating multiple pathways,including the cell cycle,cell apoptosis,drug metabolism,inflammation,and immune modulation.Molecular docking results revealed a strong associative relationship between the active ingredient and core target.CONCLUSION PCRR alleviates ALI symptoms via molecular mechanisms predicted by network pharmacology.This study proposes a strategy to elucidate the mechanisms of TCM at the network pharmacology level.
文摘This paper reports the preparation of nano-TiO2 (about 10 nm) powder by the method of precipitation. In detail, some breparation conditions were investigated in order to find out how to control the grain size and reduce the agglomeration of powders. Also, the reflex spectra of nano-scale powders with different grain size were studied. It tvas found that the wave length and width of reflex spectra are connected with the grain size of nano-TiO2 powders
基金by the National Natural Science Foundation of China(No.51704301)National Defense Technology Project Foundation(No.3604031)Youth Scientific Research Foundation of LEU(No.YQ16-420802),are gratefully acknowledged.
文摘In order to investigate the burning characteristics of a 0#diesel and 3#jet fuel,a small-scale experimental bench mainly composed of a cone calorimeter was arranged.The heat release and burning rates were investigated changing the external irradiance in order to clarify the triadic relationship among these quantities.The effective heat of combustion of 0#diesel and 3#jet fuel were 38.89 MJ/kg and 43.15 MJ/kg,respectively,with the corresponding combustion efficiencies being 96.78%and 99.60%(the effective peak heat of combustion being 1.665 times the mean value for both types of fuel).According to our experimental results,the heat release rate and burning rate of 0#diesel and 3#jet fuel both grow linearly with an increase in the external irradiance.Moreover,the heat release rate and burning rate of 3#jet fuel are greater than the equivalent values for the 0#diesel.The average smoke production rate of 0#diesel grows with an increase in the external irradiance,while for the 3#jet fuel it remains approximately the same.The specific extinction area of these two kinds of fuel shows a subtle decrease with the increase of external irradiance.The time to ignition of 3#jet fuel is smaller than 0#diesel for all the considered external irradiances,which indicates that 3#jet fuel is easier to ignite than the 0#diesel.
基金Project supported by the San Disk Info Tech Shanghai,Chinathe Institute of Microelectronic Materials&Technology,School of Materials Science and Engineering,Shanghai Jiao Tong University,China。
文摘The effects of gate oxide traps on gate leakage current and device performance of metal–oxide–nitride–oxide–silicon(MONOS)-structured NAND flash memory are investigated through Sentaurus TCAD. The trap-assisted tunneling(TAT)model is implemented to simulate the leakage current of MONOS-structured memory cell. In this study, trap position, trap density, and trap energy are systematically analyzed for ascertaining their influences on gate leakage current, program/erase speed, and data retention properties. The results show that the traps in blocking layer significantly enhance the gate leakage current and also facilitates the cell program/erase. Trap density ~10^(18) cm^(-3) and trap energy ~ 1 eV in blocking layer can considerably improve cell program/erase speed without deteriorating data retention. The result conduces to understanding the role of gate oxide traps in cell degradation of MONOS-structured NAND flash memory.
基金supported by the National Natural Science Foundation of China (No.31172085)
文摘The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00 and off at 18:00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00:00, 04:00, 08:00, 12:00, 16:00 and 20:00 with 60 turtles each (Initial body weight 88.27 - 0.09 g). Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate (SGR) and RNA/ DNA:SGR=t.1586RNA/DNA-0.7097 (r = 0.9328, P = 0.0066). The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12:00 were the lowest from the six groups (P 〈 0.05). Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight (FBW), higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total.
基金This study is supported by the Key Research Base of Philosophy and Social Sciences in Shaanxi Province,Shaanxi Health Culture Research Center Projects(Grand JKWH2019-Q19)China Association for Science and Technology Graduate Science Communication Ability Promotion Project(Grant No.kxyjskpxm2019024 and kxyjskpxm2019055)+1 种基金2018 Ministry of Education Youth Fund Project of Humanities and Social Science(Grand No.18YJC860032)Liaoning Social Science Planning Fund Project(Grand No.L18DXW002).
文摘A recent novel coronavirus(COVID-19)outbreak has started since December 2019 in Wuhan,Hubei province,People’s Republic of China and has progressively expanded to various parts of China.Based on those practical problems of emergency science popularization works in the current epidemic situation,this article,from the perspective of accuracy,timeliness and acceptability of emergency science popularization,proposes that the professional science popularization knowledge should be popularized,rumor should be refuted in a timely manner,and accurate science popularization strategies should be taken for different science preference,so to provide countermeasures and guidance for problems in emergency science popularization.
基金supported by the National Natural Science Foundation of China (Nos.42175084,21577126,and 41561144004)the Department of Science and Technology of China (Nos.2018YFC0213506,2018YFC0213503,and 2016YFC0202702)+4 种基金the National Research Program for Key Issues in Air Pollution Control in China (No.DQGG0107)supported by the“Zhejiang 1000 Talent Plan”and Research Center for Air Pollution and Health in Zhejiang UniversityPengfei Li is supported by the National Natural Science Foundation of China (No.22006030)the Initiation Fund for Introducing Talents of Hebei Agricultural University (No.412201904)the Hebei Youth Top Q15 Fund (No.BJ2020032)。
文摘To guarantee the blue skies for the 2022 Winter Olympics held in Beijing and Zhangjiakou from February 4 to 20,Beijing and its surrounding areas adopted a series of emission control measures.This provides an opportunity to determine the impacts of large-scale temporary control measures on the air quality in Beijing during this special period.Here,we applied the WRF-CMAQ model to quantify the contributions of emission reduction measures and meteorological conditions.Results show that meteorological conditions in 2022 decreased PM_(2.5)in Beijing by 6.9 and 11.8μg/m^(3)relative to 2021 under the scenarios with and without emission reductions,respectively.Strict emission reduction measures implemented in Beijing and seven neighboring provinces resulted in an average decrease of 13.0μg/m^(3)(-41.2%)in PM_(2.5)in Beijing.Over the entire period,local emission reductions contributed more to good air quality in Beijing than nonlocal emission reductions.Under the emission reduction scenario,local,controlled regions,other regions,and boundary conditions contributed 47.7%,42.0%,5.3%,and 5.0%to the PM_(2.5)concentrations in Beijing,respectively.The results indicate that during the cleaning period with the air masses from the northwest,the abatements of PM_(2.5)were mainly caused by local emission reductions.However,during the potential pollution period with the air masses from the east-northeast and west-southwest,the abatements of PM_(2.5)were caused by both local and nonlocal emission reductions almost equally.This implies that regional coordinated prevention and control strategies need to be arranged scientifically and rationally when heavy pollution events are forecasted.
基金This study was financially supported by National Natural Science Foundation of China(No.41672078)the China Geological Survey(No.DD20190606).
文摘The Aqishan-Yamansu metallogenic belt(AYMB)in East Tianshan hosts abundant sub-marine volcanic-hosted iron deposits.Although there is agreement with the magmatic source of the ore-forming materials and the role of hydrothermal replacement in iron ore formation,the mineraliza-tion processes of these iron deposits remain uncertain.Three ore types are identified on the basis of the geological occurrences of minerals and the sequence of mineral in ores.The typeⅠores are characte-rized by magnetite,diopside,amphibole with a few pyrite,and chalcopyrite.The type II ores are mainly composed of magnetite,garnet,chlorite with a few pyrite,while the type III ores are mainly composed of magnetite,quartz,calcite with a few pyrite.In order to constrain the mineralization processes of these ore types,we performed iron isotopes and trace element compositions of magnetite from three typical iron deposits(Yamansu,Duotoushan and Luotuofeng).Trace element and Fe isotope investiga-tions of the three ore types reveal two major groups.The groupⅠconsists of analyses of the typeⅠandⅡores,with both showing a narrow range of positiveδ56Fe values(+0.08‰to+0.22‰for typeⅠores and+0.15‰ to+0.22‰ for typeⅡores)and plotting in the range of the ortho-magmatic field.In contrast,the group 2 is composed merely of the typeⅢores,showing a wider range of negativeδ56Fe values(-0.49‰ to-0.01‰),which is similar to the features of Fe-skarn magnetite.As shown in the binary dia-grams of magnetite trace elements and a fractionation of the Fe isotopes,different ore types were likely produced during gradually changing ore-forming stages from magmatic to hydrothermal.Collectively,the submarine volcanic-hosted iron deposits in the East Tianshan are likely the results of a continuous magmatic-hydrothermal mineralization process.
文摘The 5-methylcytosine DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)-mediated active DNA demethylation is critical for shaping the genomic DNA methylation landscape in Arabidopsis.Whether and how the stability of ROS1 may be regulated by post-translational modifications is unknown.Using a methylation-sensitive PCR(CHOP-PCR)-based forward genetic screen forArabidopsis DNA hyper-methyl-ation mutants,we identified the SUMO E3 ligase SIZ1 as a critical regulator of active DNA demethylation.Dysfunction of SIZ1 leads to hyper-methylation at approximately 1000 genomic regions.SIZ1 physically in-teracts with ROS1 and mediates the SUMOylation of ROS1.The SUMOylation of ROS1 is reduced in siz1 mutant plants.Compared with that in wild-type plants,the protein level of ROS1 is significantly decreased,whereas there is an increased level of ROS1 transcripts in siz1 mutant plants.Our results suggest that SIZ1-mediated SUMOylation of ROS1 promotes its stability and positively regulates active DNA demethylation.
基金the support of the Key Programmer of Natural Science Foundation of China(No.50932004)the International Technology Cooperation Project from the Ministry of Science and Technology of China(No.2011DFA52680)+3 种基金the National Natural Science Foundation of China(No.51102189)the Key Grant Project of Chinese Ministry of Education(No.309022)the program for New Century Excellent Talents in University(No.NCET-11-0685)the Fundamental Research Funds for the Central Universities(No.2012-IV-006).
文摘In the current work,the bulk ternary(0.85-x)BiFeO3-xBaTiO3-0.15PbTiO3(BF-BTx-PT,x=0.08-0.35)system has been studied as a potential high-temperature piezoceramics.Samples with various content of BT were prepared via solid-state route,and pure perovskite phase was confirmed by X-ray diffraction.The temperature dependence of dielectric constants confirmed the decrease of Curie temperature with increasing BT content.It was found that the morphotropic phase boundary(MPB)composition of BF-BTx-PT ceramics was in the vicinity of x=0.15,which exhibits optimal properties with piezoelectric constant d33 of 60 pC/N,high Curie temperature of 550℃,and low sintering temperature of 920℃.Measurements also showed that the depoling temperature was 300℃,about 150℃higher than that of commercialized PZT ceramics,which indicated good temperature stability.BF-BTx-PT ceramics are promising candidates for high temperature applications.