Tetragonal zirconia (T-ZrO2) ceramic nanopowders stabilized with 3 mol% Y2O3 were synthesized via polyacrylamide gel method, using ZrOCl2?8H2O and Y(NO3)3?6H2O as raw materials. The effect of temperature on phase comp...Tetragonal zirconia (T-ZrO2) ceramic nanopowders stabilized with 3 mol% Y2O3 were synthesized via polyacrylamide gel method, using ZrOCl2?8H2O and Y(NO3)3?6H2O as raw materials. The effect of temperature on phase composition and morphology of YSZ nanopowders and sintering behavior of YSZ ceramics was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Vickers hardness tester. The aging-resistance of YSZ ceramics was measured by means of aging experiments. The results demonstrated that the phase composition of YSZ ceramic nanopowders had no obvious change and it was composed of T-ZrO2. Particle size of well-dispersed YSZ ceramic nanopowders increased from 17 to 35 nm with increasing calcining temperature from 600 to 800 ℃. There was noticeable negative correlation between calcining temperature and the relative density of YSZ ceramic at the same sintering temperature. The aging experiments showed that water vapor facilitated tetragonal to monoclinic phase transformation, and the sample that had smaller grain size exhibited better aging-resistance. It can be concluded that when the calcining temperature is 600 ℃ and sintering temperature is 1550 ℃, the relative density and hardness of YSZ ceramic arrive at the peak of 96.64% and 11.135 GPa respectively, and it has less microcracks and excellent aging-resistance.展开更多
目的观察头颈部原发结外弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)临床病理特征,为预后预测及个体化治疗提供依据。方法收集2010年1月至2020年11月新疆医科大学第一附属医院耳鼻咽喉科、血液科、肿瘤科连续确诊为头颈...目的观察头颈部原发结外弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)临床病理特征,为预后预测及个体化治疗提供依据。方法收集2010年1月至2020年11月新疆医科大学第一附属医院耳鼻咽喉科、血液科、肿瘤科连续确诊为头颈部原发结外DLBCL的患者62例。结果DLBCL中,男性38例,女性24例,中位年龄为58岁;形态学以中心母细胞型为主,可见星空现象、凝固性坏死,核分裂像和凋亡小体易见;Han’s分型GCB型23例,ABC型34例,无法分类的5例;MYC/bcl-6基因重排双打击淋巴瘤(MYC/bcl-6 DHL)2例,其中1例为双打击合并三表达。Ann Arbor分期早期20例,晚期42例,早期和晚期死亡百分比无差异(χ^(2)=0.707,P=0.400>0.05),早期比晚期的中位生存期长。EB病毒(Epstein-Barr virus,EBV)病毒阳性者2例,中位生存期51个月;EB病毒阴性者31例,中位生存期24个月。生存分析提示:综合治疗方式比手术或化疗的预后好(χ^(2)=8.554,P=0.003<0.05)。结论DLBCL患者综合治疗方式比单纯手术或化疗预后好,期待早期在个体化治疗的基础上开展综合治疗。展开更多
在智能电表中,结算方式已经由原有的电量结算转换为金额结算,并且费率模式也较以往的电表更为复杂,这些需求对智能电表中的实时钟(Real Time Clock,RTC)提出了更高的要求。而众所周知,影响实时钟精度的主要原因为晶体的温度偏差,晶体的...在智能电表中,结算方式已经由原有的电量结算转换为金额结算,并且费率模式也较以往的电表更为复杂,这些需求对智能电表中的实时钟(Real Time Clock,RTC)提出了更高的要求。而众所周知,影响实时钟精度的主要原因为晶体的温度偏差,晶体的温度曲线接近二次曲线,因此用二次曲线校正的方法,可修正晶体的温度偏差,从而提升智能电表的实时钟精度。展开更多
基金Funded by the National Natural Science Foundation of China(No.51964035)the Natural Science Foundation of Inner Mongolia Autonomous Region(No.2019MS0520)。
文摘Tetragonal zirconia (T-ZrO2) ceramic nanopowders stabilized with 3 mol% Y2O3 were synthesized via polyacrylamide gel method, using ZrOCl2?8H2O and Y(NO3)3?6H2O as raw materials. The effect of temperature on phase composition and morphology of YSZ nanopowders and sintering behavior of YSZ ceramics was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Vickers hardness tester. The aging-resistance of YSZ ceramics was measured by means of aging experiments. The results demonstrated that the phase composition of YSZ ceramic nanopowders had no obvious change and it was composed of T-ZrO2. Particle size of well-dispersed YSZ ceramic nanopowders increased from 17 to 35 nm with increasing calcining temperature from 600 to 800 ℃. There was noticeable negative correlation between calcining temperature and the relative density of YSZ ceramic at the same sintering temperature. The aging experiments showed that water vapor facilitated tetragonal to monoclinic phase transformation, and the sample that had smaller grain size exhibited better aging-resistance. It can be concluded that when the calcining temperature is 600 ℃ and sintering temperature is 1550 ℃, the relative density and hardness of YSZ ceramic arrive at the peak of 96.64% and 11.135 GPa respectively, and it has less microcracks and excellent aging-resistance.
文摘在智能电表中,结算方式已经由原有的电量结算转换为金额结算,并且费率模式也较以往的电表更为复杂,这些需求对智能电表中的实时钟(Real Time Clock,RTC)提出了更高的要求。而众所周知,影响实时钟精度的主要原因为晶体的温度偏差,晶体的温度曲线接近二次曲线,因此用二次曲线校正的方法,可修正晶体的温度偏差,从而提升智能电表的实时钟精度。
基金National Natural Science Foundation of China (51964035)Natural Science Foundation of Inner Mongolia Autonomous Region (2019MS0520)Natural Science Foundation of Inner Mongolia Autonomous Region (2020LH05017)。
基金National Natural Science Foundation of China(51964035)Natural Science Foundation of Inner Mongolia Autonomous Region(2019MS05020,2020LH05017)Science and Technology Major Project of Inner Mongolia Autonomous Region(2018-810)。
