为研究铁尾砂泡沫混凝土抗冻融性能, 制备了5组目标密度为900 kg/m3的泡沫混凝土, 在硫酸盐环境下冻融循环后, 对比分析不同铁尾砂掺量泡沫混凝土的质量损失、强度损失、孔隙面积率和微观结构。以质量损失和强度损失为衡量指标, 评选最优配合比, 基于Wiener退化过程进行可靠度分析并预测剩余寿命。结果表明: 在硫酸盐冻融循环过程中, 泡沫混凝土表面损伤, 内部孔隙连通形成裂缝, 各试件质量呈先增加后减少的趋势; 抗压强度和孔隙面积率持续下降, 细粒径铁尾砂的掺入有效缓解了泡沫混凝土的损伤。其中, 20%(质量分数)铁尾砂掺量的泡沫混凝土抗冻融能力最强, 试件经过约300次冻融循环后失效。本研究可为泡沫混凝土在冻土地区的应用提供思路。
铁尾砂 泡沫混凝土 冻融循环 硫酸盐环境 Wiener退化过程 iron tailings sand foam concrete freeze-thaw cycle sulfate environment Wiener degradation process
Author Affiliations
Abstract
1 State Key Laboratory of Silicon Materials, Key Laboratory for Biomedical Engineering of Ministry of Education, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
2 Wenzhou Key Laboratory of Novel Optoelectronic and Nano Materials, Institute of Wenzhou, Zhejiang University, Wenzhou 325006, China
3 Department of Electronic Science and Technology, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
4 Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
Amorphous oxide semiconductors (AOS) have unique advantages in transparent and flexible thin film transistors (TFTs) applications, compared to low-temperature polycrystalline-Si (LTPS). However, intrinsic AOS TFTs are difficult to obtain field-effect mobility (μFE) higher than LTPS (100 cm2/(V·s)). Here, we design ZnAlSnO (ZATO) homojunction structure TFTs to obtainμFE = 113.8 cm2/(V·s). The device demonstrates optimized comprehensive electrical properties with an off-current of about 1.5 × 10–11 A, a threshold voltage of –1.71 V, and a subthreshold swing of 0.372 V/dec. There are two kinds of gradient coupled in the homojunction active layer, which are micro-crystallization and carrier suppressor concentration gradient distribution so that the device can reduce off-current and shift the threshold voltage positively while maintaining high field-effect mobility. Our research in the homojunction active layer points to a promising direction for obtaining excellent-performance AOS TFTs.
thin film transistors homojunction carrier mobility amorphous oxides Journal of Semiconductors
2023, 44(5): 052101
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences,University of the Chinese Academy of Sciences, Changchun 130022, China
High efficient yellow organic light emitting diodes (OLEDs) based on exciplex were reported. The exciplex was formed by 4, 4′, 4′′-tris [3-methylphenyl (phenyl) amino]-triphenylamine (m-MTDATA) and 4, 7- diphenyl-1, 10-phenanthroline (BPhen). The resulting yellow OLEDs exhibited an external quantum efficiency of over 7%, which is attributed to the effective energy back transfer from exciplex triplet state to exciplex singlet state. The maximum power efficiency of 25 lm/W was achieved. Doping a yellow phosphor Ir(bt)2(acac) into m-MTDATA: BPhen blend, a high efficiency device was achieved with a turn-on voltage of 2.1 V, maximum power efficiency and external quantum efficiency of 86.1 lm/W and 20.7%, respectively.
organic light-emitting diodes (OLEDs) organic light-emitting diodes (OLEDs) fluorescent fluorescent exciplex exciplex Frontiers of Optoelectronics
2015, 8(4): 439
1 贵州师范大学 化学与材料科学学院, 贵阳 550001
2 贵州省功能材料化学重点实验室, 贵阳 550001
3 贵州师范大学 职业技术学院, 贵阳 550001
采用水热法结合H2SO4浸泡处理成功合成了SO2-4/Bi2O3可见光催化材料, 并采用XRD、TGDTA和UVVis等对合成产物的物相结构、热化学性能、光吸收性能以及可见光催化性能进行了研究, 对H2SO4浸泡工艺条件对产物的可见光催化性能的影响进行了探讨。研究表明, 水热合成产物为αBi2O3、Bi2O4和Bi2O2CO3的混合物, 其中αBi2O3为主要成分；H2SO4浸泡处理并未改变产物的物相结构, 但经H2SO4浸泡处理后产物的光催化性能得到了显著的提高, 并且H2SO4浸泡工艺条件对产物的光催化活性有着重要的影响。在实验范围内, 在浓度为0.5mol·L-1的H2SO4溶液中浸泡75min, 再经700℃热处理4h可制备出具有较佳光催化活性的产物, 经75min可见光的照射后对甲基橙溶液的光催化脱色率可达93.1%。
固体超酸 浸泡处理 可见光催化 solid superacid SO2-4/Bi2O3 SO2-4/Bi2O3 dipping treatment visiblelight photocatalyst
1 贵州师范大学化学与材料科学学院, 贵阳 550001
2 贵州省功能材料化学重点实验室, 贵阳 550001
3 贵州师范大学职业技术学院, 贵阳 550001
以Bi(NO3)3·5H2O和NH4VO3为原材料, 采用水热法合成了BiVO4可见光催化材料, 并采用XRD、SEM和UV-Vis等对合成产物的物相结构、形貌、光吸收性能以及光催化性能进行了研究。研究表明,反应体系的pH值对合成产物的物相结构具有重要的影响, 在酸性和弱碱性条件下可获得具有不规则纳米片状形貌的单斜白钨矿结构BiVO4晶体。合成产物对波长小于525nm的光具有强烈的吸收。水热条件的不同直接影响着产物对甲基橙溶液的可见光催化降解性能, 在Bi∶V比例为1∶1, 同时pH值为3.08并于160℃下水热处理1h所合成的BiVO4晶体对甲基橙溶液具有最佳的可见光催化活性。
水热法 单斜白钨矿结构 光催化 hydrothermal method BiVO4 BiVO4 monoclinic scheelite structure photocatalysis
State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, China
Frontiers of Optoelectronics
2008, 1(1): 147
