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
A series of nominal compositions MgAl_(2-x)(Li_(1/3)Ti_(2/3))_(x)O_(4)(x=0,0.04,0.08,0.12,0.16,and 0.20)ceramics were successfully prepared via the conventional solid-state reaction route.The phase compositions,micros...A series of nominal compositions MgAl_(2-x)(Li_(1/3)Ti_(2/3))_(x)O_(4)(x=0,0.04,0.08,0.12,0.16,and 0.20)ceramics were successfully prepared via the conventional solid-state reaction route.The phase compositions,microstructures,and microwave dielectric properties were investigated.The results of x-ray diffraction(XRD)and scanning electron microscopy(SEM)showed that a single phase of MgAl_(2-x)(Li_(1/3)Ti_(2/3))_(x)O_(4)ceramics with a spinel structure was obtained at x≤0.12,whereas the second phase of MgTi_(2)O_(5)appeared when x>0.12.The cell parameters were obtained by XRD refinement.As the x values increased,the unit cell volume kept expanding.This phenomenon could be attributed to the partial substitution of(Li_(1/3)Ti_(2/3))^(3+)for Al^(3+).Results showed that(Li_(1/3)Ti_(2/3))^(3+)doping into MgAl_(2)O_(4)spinel ceramics effectively reduced the sintering temperature and improved the quality factor(Q_f)values.Good microwave dielectric properties were achieved for a sample at x=0.20 sintering at 1500℃in air for 4 h:dielectric constantε_(r)=8.78,temperature coefficient of resonant frequencyτ_(f)=-85 ppm/℃,and Q_(f)=62300 GHz.The Q_(f)value of the x=0.20 sample was about 2 times higher than that of pure MgAl_(2)O_(4)ceramics(31600 GHz).Thus,MgAl_(2-x)(Li_(1/3)Ti_(2/3))_(x)O_(4)ceramics with excellent microwave dielectric properties can be applied to 5G communications.展开更多
基金supported by the National Natural Science Foundation of China (No.52004044)the Natural Science Foundation of Chongqing,China (No.CSTB2022NSCQ-MSX0801)+3 种基金the Foundation of Chongqing University of Science and Technology,China (No.ckrc2022030)the Graduate Research Innovation Project of Chongqing University of Science and Technology,China (No.YKJCX2220214)the Science and Technology Innovation Training Program of Chongqing University of Science and Technology,China (No.2022046)the College Students’Innovation and Entrepreneurship Training Program of Chongqing University of Science and Technology,China (No.2022007).
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。
基金the Chengdu University of Technology(Grant No.KYQD201907728)。
文摘A series of nominal compositions MgAl_(2-x)(Li_(1/3)Ti_(2/3))_(x)O_(4)(x=0,0.04,0.08,0.12,0.16,and 0.20)ceramics were successfully prepared via the conventional solid-state reaction route.The phase compositions,microstructures,and microwave dielectric properties were investigated.The results of x-ray diffraction(XRD)and scanning electron microscopy(SEM)showed that a single phase of MgAl_(2-x)(Li_(1/3)Ti_(2/3))_(x)O_(4)ceramics with a spinel structure was obtained at x≤0.12,whereas the second phase of MgTi_(2)O_(5)appeared when x>0.12.The cell parameters were obtained by XRD refinement.As the x values increased,the unit cell volume kept expanding.This phenomenon could be attributed to the partial substitution of(Li_(1/3)Ti_(2/3))^(3+)for Al^(3+).Results showed that(Li_(1/3)Ti_(2/3))^(3+)doping into MgAl_(2)O_(4)spinel ceramics effectively reduced the sintering temperature and improved the quality factor(Q_f)values.Good microwave dielectric properties were achieved for a sample at x=0.20 sintering at 1500℃in air for 4 h:dielectric constantε_(r)=8.78,temperature coefficient of resonant frequencyτ_(f)=-85 ppm/℃,and Q_(f)=62300 GHz.The Q_(f)value of the x=0.20 sample was about 2 times higher than that of pure MgAl_(2)O_(4)ceramics(31600 GHz).Thus,MgAl_(2-x)(Li_(1/3)Ti_(2/3))_(x)O_(4)ceramics with excellent microwave dielectric properties can be applied to 5G communications.
