针对高放废液硼硅酸盐玻璃固化体易析出辉石晶相的问题,本文采用P_(2)O_(5)部分替代硼硅酸盐基础玻璃配方中的MgO和CaO,研究了P_(2)O_(5)掺量(质量分数为0~8%)对玻璃固化体析晶和抗浸出性能的影响。结果表明,当P_(2)O_(5)掺量为0~3%时,...针对高放废液硼硅酸盐玻璃固化体易析出辉石晶相的问题,本文采用P_(2)O_(5)部分替代硼硅酸盐基础玻璃配方中的MgO和CaO,研究了P_(2)O_(5)掺量(质量分数为0~8%)对玻璃固化体析晶和抗浸出性能的影响。结果表明,当P_(2)O_(5)掺量为0~3%时,样品为无定形态,在850℃热处理6 h后,P_(2)O_(5)掺量为0~2%的样品主要析出辉石晶相,而P_(2)O_(5)掺量为3%的样品析出了少量硅酸钙晶相,辉石晶相基本消失;当P_(2)O_(5)掺量高于3%时,样品析出球形Na_(3)Ca_(6)(PO_(4))_(5)晶体,且析晶度随P_(2)O_(5)掺量的增加而升高。29 Si MAS NMR和^(11)B MAS NMR分析表明,随着P_(2)O_(5)掺量的增加,玻璃网络结构中Q^(3)、Q^(4)和BO_(3)结构单元含量逐渐增加。静态浸泡法(MCC-1)试验结果表明,样品的抗浸出性能随P_(2)O_(5)掺量的增加而逐渐提高,其中P_(2)O_(5)掺量为3%的样品浸泡28 d后,Si、B、Na和Cs元素的归一化浸出率分别为0.508、0.468、0.533、0.280 g/(m^(2)·d)。展开更多
目的:研究不同含量P_(2)O_(5)替代SiO对生物活性玻璃的力学性能及生物活性的影响。方法:应用高温熔融法烧制各组分基础玻璃,P_(2)O_(5)含量分别为0wt%、1wt%、3wt%、6wt%、9wt%、12wt%。以聚氨酯海绵为模板,有机泡沫浸渍法制作多孔生物...目的:研究不同含量P_(2)O_(5)替代SiO对生物活性玻璃的力学性能及生物活性的影响。方法:应用高温熔融法烧制各组分基础玻璃,P_(2)O_(5)含量分别为0wt%、1wt%、3wt%、6wt%、9wt%、12wt%。以聚氨酯海绵为模板,有机泡沫浸渍法制作多孔生物活性玻璃支架。万能力学试验机单轴压缩和三点弯曲法测试支架的力学性能,标准模拟体液(simulated body fluid,SBF)浸泡计算质量损失百分比及扫描电镜(scanning electron microscope,SEM)观察、X线衍射分析(X-ray diffraction,XRD)观测生物活性。结果:(1)五组多孔支架的抗压强度及抗弯强度测试结果显示,除P_(2)O_(5)含量为0wt%和1wt%两组无显著差异外,随P_(2)O_(5)含量增高材料的力学性能逐渐增强,但当P_(2)O_(5)含量达到12wt%时支架无法烧制成型。(2)五组多孔支架浸泡实验结果表示,高磷含量组材料降解性能强于低磷含量组。且随着浸泡时间延长,除P_(2)O_(5)含量为0wt%和1wt%两组无显著差异外,其余各组之间降解性能有显著差异。(3)在SBF中浸泡后SEM及XRD检测发现,P_(2)O_(5)含量为0wt%和1wt%两组无体外矿化活性,其余各组有矿化活性,且随P_(2)O_(5)含量增高材料体外矿化活性逐渐增强。结论:(1)添加一定量的P_(2)O_(5)可以显著增强生物活性玻璃的力学性能,但含量达到12wt%时支架无法成型;(2)P_(2)O_(5)可以显著增强生物活性玻璃的降解性能及体外矿化活性。展开更多
介绍了河钢石钢采用60 t BOF-LF-VD-CC流程,V_(2)O_(5)直接合金化生产含钒钢的工艺试验过程,并从钒的吸收率、吨钢成本、夹杂物级别以及氧含量等方面与钒铁工艺进行了对比。结果表明,V_(2)O_(5)直接合金化工艺中,V_(2)O_(5)与Al按照质量...介绍了河钢石钢采用60 t BOF-LF-VD-CC流程,V_(2)O_(5)直接合金化生产含钒钢的工艺试验过程,并从钒的吸收率、吨钢成本、夹杂物级别以及氧含量等方面与钒铁工艺进行了对比。结果表明,V_(2)O_(5)直接合金化工艺中,V_(2)O_(5)与Al按照质量比2∶1的比例在炉后加入钢包内,V_(2)O_(5)的吸收率与钒铁工艺相当,能稳定在99%左右;钢中每增加0.01%钒吨钢成本比钒铁工艺降低2.92元;且使用V_(2)O_(5)增钒夹杂物与氧含量与钒铁工艺基本持平,对钢水质量没影响。展开更多
A series of 20Li_(2)O-30V_(2)O_(5)-(50-x)SiO_(2)-xB_(2)O_(3)(mol.%)(x=10,20,30,40)glasses were prepared by the traditional melt-quenching synthesis.The amorphous nature of the glasses was determined by XRD,DSC and TEM...A series of 20Li_(2)O-30V_(2)O_(5)-(50-x)SiO_(2)-xB_(2)O_(3)(mol.%)(x=10,20,30,40)glasses were prepared by the traditional melt-quenching synthesis.The amorphous nature of the glasses was determined by XRD,DSC and TEM investigations.FTIR measurement revealed the functional group of obtained glasses.And EDS results confirmed the presence and uniform distribution of elements in the glasses.20Li_(2)O-30V_(2)O_(5)-40SiO_(2)-10B_(2)O_(3)(LVSB10)sample with the highest V^(4+) ratio exhibited the best cycling capacity.In order to further improve cycling stability of LVSB10 sample,ball milling was employed to reduce the particle size.The ball milled LVSB10 sample(LVSB10-b)showed an improved first discharge capacity,cycling stability and rate capacity.EIS measurements showed that ball milling can effectively decrease charge transfer impedance and facilitate Li^(+) ion diffusion.This work provides a new way to explore a new type of cathode materials for lithium ion batteries.展开更多
Transparent Ce:lutetium aluminum garnet(Ce:Lu_(3)A_(l5)O_(12),Ce:LuAG)ceramics have been regarded as potential scintillator materials due to their relatively high density and atomic number(Zeff).However,the current Ce...Transparent Ce:lutetium aluminum garnet(Ce:Lu_(3)A_(l5)O_(12),Ce:LuAG)ceramics have been regarded as potential scintillator materials due to their relatively high density and atomic number(Zeff).However,the current Ce:LuAG ceramics exhibit a light yield much lower than the expected theoretical value due to the inevitable presence of LuAl antisite defects at high sintering temperatures.This work demonstrates a low-temperature(1100℃)synthetic strategy for elaborating transparent LuAG–Al_(2)O_(3) nanoceramics through the crystallization of 72 mol%Al_(2)O_(3)–28 mol%Lu_(2)O_(3)(ALu28)bulk glass.The biphasic nanostructure composed of LuAG and Al_(2)O_(3) nanocrystals makes up the whole ceramic materials.Most of Al_(2)O_(3) is distributed among LuAG grains,and the rest is present inside the LuAG grains.Fully dense biphasic LuAG–Al_(2)O_(3) nanoceramics are highly transparent from the visible region to mid-infrared(MIR)region,and particularly the transmittance reaches 82%at 780 nm.Moreover,LuAl antisite defect-related centers are completely undetectable in X-ray excited luminescence(XEL)spectra of Ce:LuAG–Al_(2)O_(3) nanoceramics with 0.3–1.0 at%Ce.The light yield of 0.3 at%Ce:LuAG–Al_(2)O_(3) nanoceramics is estimated to be 20,000 ph/MeV with short 1μs shaping time,which is far superior to that of commercial Bi_(4)Ge_(3)O_(12)(BGO)single crystals.These results show that a low-temperature glass crystallization route provides an alternative approach for eliminating the antisite defects in LuAG-based ceramics,and is promising to produce garnet-based ceramic materials with excellent properties,thereby meeting the demands of advanced scintillation applications.展开更多
La-and Nb-doped BaTi_(2)O_(5)(BT2)spherical glasses were prepared by a containerless aerodynamic levitation method and their glass-forming regions were established.It is found that La-doping on the Ba-site(network-mod...La-and Nb-doped BaTi_(2)O_(5)(BT2)spherical glasses were prepared by a containerless aerodynamic levitation method and their glass-forming regions were established.It is found that La-doping on the Ba-site(network-modifier)and Nb-doping on the Ti-site(network-former)show distinct difference in the glassforming region:less than 10%La can replace Ba whereas 40%Nb can incorporate into BT2 glass.The distinction in glass-forming ability induced by La-and Nb-doping is discussed mainly from the structural arrangement of the glass.Raman spectroscopy analysis shows that La-doping elongates the short Ti-O bonds in the distorted[TiO_(5)]polyhedra and thus relaxes the network.Nb-doping introduces[NbO_(6)]polyhedra into BT_(2) and there exists a critical doping level(20%),below which incorporation of Nb into BT_(2) relaxes the[TiOn]polyhedra by shortening the long Ti-O bond and above which[NbO_(6)]starts to participate in the network skeleton construction resulting in a dramatic change in the glass structure,which is supported by the dramatic change in the exothermic peak on the DTA curves.This work triggers the speculation that the network-modifiers in BT_(2) glass possess a very important role in the structure of network-former skeleton than those in glasses based on traditional network-former oxides such as SiO_(2),GeO_(2) and B_(2)O_(3),which may provide a useful strategy for modifying the properties of these novel glasses by chemical doping.展开更多
Ce doped Lu_(3)Al_(5)O_(12)(Ce:LuAG)transparent ceramics are considered as promising color converters for solid-state lighting because of their excellent luminous efficiency,high thermal quenching temperature,and good...Ce doped Lu_(3)Al_(5)O_(12)(Ce:LuAG)transparent ceramics are considered as promising color converters for solid-state lighting because of their excellent luminous efficiency,high thermal quenching temperature,and good thermal stability.However,Ce:LuAG ceramics mainly emit green light.The shortage of red light as well as the expensive price of Lu compounds are hindering their application for white lighting.In this work,transparent(Lu,Gd)_(3)Al_(5)O_(12)–Al_(2)O_(3)(LuGAG–Al_(2)O_(3))nanoceramics with different replacing contents of Gd^(3+)(10%–50%)were successfully elaborated via a glass-crystallization method.The obtained ceramics with full nanoscale grains are composed of the main LuGAG crystalline phase and secondary Al_(2)O_(3) phase,exhibiting eminent transparency of 81.0%@780 nm.After doping by Ce^(3+),the Ce:LuGAG–Al_(2)O_(3) nanoceramics show a significant red shift(510 nm→550 nm)and make up for the deficiency of red light component in the emission spectrum.The Ce:LuAG–Al_(2)O_(3) nanoceramics with 20%Gd^(3+)show high internal quantum efficiency(81.5%in internal quantum efficiency(IQE),96.7%of Ce:LuAG–Al_(2)O_(3) nanoceramics)and good thermal stability(only 9%loss in IQE at 150℃).When combined with blue LED chips(10 W),0.3%Ce:LuGAG–Al_(2)O_(3) nanoceramics with 20%Gd^(3+)successfully realize the high-quality warm white LED lighting with a color coordinate of(0.3566,0.435),a color temperature of 4347 K,CRI of 67.7,and a luminous efficiency of 175.8 lm·W^(−1).When the transparent 0.3%Ce:LuGAG–Al_(2)O_(3) nanoceramics are excited by blue laser(5 W·mm^(−2)),the emission peak position redshifts from 517 to 570 nm,the emitted light exhibits a continuous change from green light to yellow light,and then to orange-yellow light,and the maximum luminous efficiency is up to 234.49 lm·W^(−1)(20%Gd^(3+)).Taking into account the high quantum efficiency,good thermal stability,and excellent and adjustable luminous properties,the transparent Ce:LuGAG–Al_(2)O_(3) nanoceramics with different Gd^(3+)substitution contents in this paper are believed to be promising candidates for high-power white LED/LD lighting.展开更多
文摘针对高放废液硼硅酸盐玻璃固化体易析出辉石晶相的问题,本文采用P_(2)O_(5)部分替代硼硅酸盐基础玻璃配方中的MgO和CaO,研究了P_(2)O_(5)掺量(质量分数为0~8%)对玻璃固化体析晶和抗浸出性能的影响。结果表明,当P_(2)O_(5)掺量为0~3%时,样品为无定形态,在850℃热处理6 h后,P_(2)O_(5)掺量为0~2%的样品主要析出辉石晶相,而P_(2)O_(5)掺量为3%的样品析出了少量硅酸钙晶相,辉石晶相基本消失;当P_(2)O_(5)掺量高于3%时,样品析出球形Na_(3)Ca_(6)(PO_(4))_(5)晶体,且析晶度随P_(2)O_(5)掺量的增加而升高。29 Si MAS NMR和^(11)B MAS NMR分析表明,随着P_(2)O_(5)掺量的增加,玻璃网络结构中Q^(3)、Q^(4)和BO_(3)结构单元含量逐渐增加。静态浸泡法(MCC-1)试验结果表明,样品的抗浸出性能随P_(2)O_(5)掺量的增加而逐渐提高,其中P_(2)O_(5)掺量为3%的样品浸泡28 d后,Si、B、Na和Cs元素的归一化浸出率分别为0.508、0.468、0.533、0.280 g/(m^(2)·d)。
文摘目的:研究不同含量P_(2)O_(5)替代SiO对生物活性玻璃的力学性能及生物活性的影响。方法:应用高温熔融法烧制各组分基础玻璃,P_(2)O_(5)含量分别为0wt%、1wt%、3wt%、6wt%、9wt%、12wt%。以聚氨酯海绵为模板,有机泡沫浸渍法制作多孔生物活性玻璃支架。万能力学试验机单轴压缩和三点弯曲法测试支架的力学性能,标准模拟体液(simulated body fluid,SBF)浸泡计算质量损失百分比及扫描电镜(scanning electron microscope,SEM)观察、X线衍射分析(X-ray diffraction,XRD)观测生物活性。结果:(1)五组多孔支架的抗压强度及抗弯强度测试结果显示,除P_(2)O_(5)含量为0wt%和1wt%两组无显著差异外,随P_(2)O_(5)含量增高材料的力学性能逐渐增强,但当P_(2)O_(5)含量达到12wt%时支架无法烧制成型。(2)五组多孔支架浸泡实验结果表示,高磷含量组材料降解性能强于低磷含量组。且随着浸泡时间延长,除P_(2)O_(5)含量为0wt%和1wt%两组无显著差异外,其余各组之间降解性能有显著差异。(3)在SBF中浸泡后SEM及XRD检测发现,P_(2)O_(5)含量为0wt%和1wt%两组无体外矿化活性,其余各组有矿化活性,且随P_(2)O_(5)含量增高材料体外矿化活性逐渐增强。结论:(1)添加一定量的P_(2)O_(5)可以显著增强生物活性玻璃的力学性能,但含量达到12wt%时支架无法成型;(2)P_(2)O_(5)可以显著增强生物活性玻璃的降解性能及体外矿化活性。
文摘介绍了河钢石钢采用60 t BOF-LF-VD-CC流程,V_(2)O_(5)直接合金化生产含钒钢的工艺试验过程,并从钒的吸收率、吨钢成本、夹杂物级别以及氧含量等方面与钒铁工艺进行了对比。结果表明,V_(2)O_(5)直接合金化工艺中,V_(2)O_(5)与Al按照质量比2∶1的比例在炉后加入钢包内,V_(2)O_(5)的吸收率与钒铁工艺相当,能稳定在99%左右;钢中每增加0.01%钒吨钢成本比钒铁工艺降低2.92元;且使用V_(2)O_(5)增钒夹杂物与氧含量与钒铁工艺基本持平,对钢水质量没影响。
基金financially supported by Shenzhen Basic Research Project Funds(JCYJ20170817161127616).
文摘A series of 20Li_(2)O-30V_(2)O_(5)-(50-x)SiO_(2)-xB_(2)O_(3)(mol.%)(x=10,20,30,40)glasses were prepared by the traditional melt-quenching synthesis.The amorphous nature of the glasses was determined by XRD,DSC and TEM investigations.FTIR measurement revealed the functional group of obtained glasses.And EDS results confirmed the presence and uniform distribution of elements in the glasses.20Li_(2)O-30V_(2)O_(5)-40SiO_(2)-10B_(2)O_(3)(LVSB10)sample with the highest V^(4+) ratio exhibited the best cycling capacity.In order to further improve cycling stability of LVSB10 sample,ball milling was employed to reduce the particle size.The ball milled LVSB10 sample(LVSB10-b)showed an improved first discharge capacity,cycling stability and rate capacity.EIS measurements showed that ball milling can effectively decrease charge transfer impedance and facilitate Li^(+) ion diffusion.This work provides a new way to explore a new type of cathode materials for lithium ion batteries.
基金supported by the National Natural Science Foundation of China (No.51972304)Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park (No.Z221100006722022)+1 种基金the Project of Scientific Experiment on Chinese Manned Space Station,Chinese Academy of Sciences President’s International Fellowship Initiative for 2021 (No.2021VEA0012)the Fundamental Research Funds for the Central Universities.
文摘Transparent Ce:lutetium aluminum garnet(Ce:Lu_(3)A_(l5)O_(12),Ce:LuAG)ceramics have been regarded as potential scintillator materials due to their relatively high density and atomic number(Zeff).However,the current Ce:LuAG ceramics exhibit a light yield much lower than the expected theoretical value due to the inevitable presence of LuAl antisite defects at high sintering temperatures.This work demonstrates a low-temperature(1100℃)synthetic strategy for elaborating transparent LuAG–Al_(2)O_(3) nanoceramics through the crystallization of 72 mol%Al_(2)O_(3)–28 mol%Lu_(2)O_(3)(ALu28)bulk glass.The biphasic nanostructure composed of LuAG and Al_(2)O_(3) nanocrystals makes up the whole ceramic materials.Most of Al_(2)O_(3) is distributed among LuAG grains,and the rest is present inside the LuAG grains.Fully dense biphasic LuAG–Al_(2)O_(3) nanoceramics are highly transparent from the visible region to mid-infrared(MIR)region,and particularly the transmittance reaches 82%at 780 nm.Moreover,LuAl antisite defect-related centers are completely undetectable in X-ray excited luminescence(XEL)spectra of Ce:LuAG–Al_(2)O_(3) nanoceramics with 0.3–1.0 at%Ce.The light yield of 0.3 at%Ce:LuAG–Al_(2)O_(3) nanoceramics is estimated to be 20,000 ph/MeV with short 1μs shaping time,which is far superior to that of commercial Bi_(4)Ge_(3)O_(12)(BGO)single crystals.These results show that a low-temperature glass crystallization route provides an alternative approach for eliminating the antisite defects in LuAG-based ceramics,and is promising to produce garnet-based ceramic materials with excellent properties,thereby meeting the demands of advanced scintillation applications.
基金the National Natural Science Foundation of China(Nos.51971138,51727802 and 51821001)the National Natural Science Foundation of ChinaExcellent Young Scholars(No.51922068)+1 种基金the National Key Research and Development Program(No.2017YFA0403800)the Shanghai Pujiang Program(No.19PJ1404400)。
文摘La-and Nb-doped BaTi_(2)O_(5)(BT2)spherical glasses were prepared by a containerless aerodynamic levitation method and their glass-forming regions were established.It is found that La-doping on the Ba-site(network-modifier)and Nb-doping on the Ti-site(network-former)show distinct difference in the glassforming region:less than 10%La can replace Ba whereas 40%Nb can incorporate into BT2 glass.The distinction in glass-forming ability induced by La-and Nb-doping is discussed mainly from the structural arrangement of the glass.Raman spectroscopy analysis shows that La-doping elongates the short Ti-O bonds in the distorted[TiO_(5)]polyhedra and thus relaxes the network.Nb-doping introduces[NbO_(6)]polyhedra into BT_(2) and there exists a critical doping level(20%),below which incorporation of Nb into BT_(2) relaxes the[TiOn]polyhedra by shortening the long Ti-O bond and above which[NbO_(6)]starts to participate in the network skeleton construction resulting in a dramatic change in the glass structure,which is supported by the dramatic change in the exothermic peak on the DTA curves.This work triggers the speculation that the network-modifiers in BT_(2) glass possess a very important role in the structure of network-former skeleton than those in glasses based on traditional network-former oxides such as SiO_(2),GeO_(2) and B_(2)O_(3),which may provide a useful strategy for modifying the properties of these novel glasses by chemical doping.
基金This work is financially supported by the National Natural Science Foundation of China(No.51972304)Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park(No.Z221100006722022)+1 种基金the Project of Scientific Experiment on Chinese Manned Space Station,Chinese Academy of Sciences President’s International Fellowship Initiative for 2021(No.2021VEA0012)the Fundamental Research Funds for the Central Universities.The project benefitted from the microscopy facilities of the Platform MACLE-CVL which was co-funded by the European Union and Centre-Val de Loire Region(FEDER).Declaration of competing interest。
文摘Ce doped Lu_(3)Al_(5)O_(12)(Ce:LuAG)transparent ceramics are considered as promising color converters for solid-state lighting because of their excellent luminous efficiency,high thermal quenching temperature,and good thermal stability.However,Ce:LuAG ceramics mainly emit green light.The shortage of red light as well as the expensive price of Lu compounds are hindering their application for white lighting.In this work,transparent(Lu,Gd)_(3)Al_(5)O_(12)–Al_(2)O_(3)(LuGAG–Al_(2)O_(3))nanoceramics with different replacing contents of Gd^(3+)(10%–50%)were successfully elaborated via a glass-crystallization method.The obtained ceramics with full nanoscale grains are composed of the main LuGAG crystalline phase and secondary Al_(2)O_(3) phase,exhibiting eminent transparency of 81.0%@780 nm.After doping by Ce^(3+),the Ce:LuGAG–Al_(2)O_(3) nanoceramics show a significant red shift(510 nm→550 nm)and make up for the deficiency of red light component in the emission spectrum.The Ce:LuAG–Al_(2)O_(3) nanoceramics with 20%Gd^(3+)show high internal quantum efficiency(81.5%in internal quantum efficiency(IQE),96.7%of Ce:LuAG–Al_(2)O_(3) nanoceramics)and good thermal stability(only 9%loss in IQE at 150℃).When combined with blue LED chips(10 W),0.3%Ce:LuGAG–Al_(2)O_(3) nanoceramics with 20%Gd^(3+)successfully realize the high-quality warm white LED lighting with a color coordinate of(0.3566,0.435),a color temperature of 4347 K,CRI of 67.7,and a luminous efficiency of 175.8 lm·W^(−1).When the transparent 0.3%Ce:LuGAG–Al_(2)O_(3) nanoceramics are excited by blue laser(5 W·mm^(−2)),the emission peak position redshifts from 517 to 570 nm,the emitted light exhibits a continuous change from green light to yellow light,and then to orange-yellow light,and the maximum luminous efficiency is up to 234.49 lm·W^(−1)(20%Gd^(3+)).Taking into account the high quantum efficiency,good thermal stability,and excellent and adjustable luminous properties,the transparent Ce:LuGAG–Al_(2)O_(3) nanoceramics with different Gd^(3+)substitution contents in this paper are believed to be promising candidates for high-power white LED/LD lighting.
