分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-08-18
摘要: We present a novel strategy for simultaneous doping of Cu ions into TiO2 nanocrystals and transforming amorphous anodic TiO2 nanotubes (TNTs) into anatase nanoparticle (NP) array film. Highly reactive colloidal Cu clusters derived by laser ablation in liquids were used as doping precursor, which can react with amorphous TiO2 nanotubes to form doped anatase NPs by dissolution and recrystallization processes. The Cu-doped TiO2 NPs (Cu-TNPs) film was characterized by X-ray diffraction, scanning and transmission electron microscopy and Raman spectroscopy. The Cu-TNPs show a rugby-like shape with exposed active {101}, {001} facets and the long-axis parallel to [001] lattice direction. The substitutional Cu2+ ions dopants in TiO2 nanocrystals caused the swelling of the crystalline unit cell, red shift of the absorption edge, and enhanced absorption in the visible-light region. The green and efficient doping design would facilliate the ongoing effort toward improving nanostructured TiO2 as a practical biosensor for glucose molecules.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-08-18
摘要: We report the coexistence of resistance switching (RS) behavior and negative differential resistance (NDR) phenomenon in α-Fe2O3 nanorod film grown in situ on fluorine-doped tin oxide glass substrate. The reversible switching of the low- and high-resistance states (LRS and HRS, respectively) of the film device can be excited simply by applying bias voltage. The switching from HRS to LRS was initiated at the negative bias region, whereas the NDR process followed by the reversion of HRS occurred at the positive bias region. With the increase in compliant current (CC), the carrier conduction models of LRS and HRS both changed and the current–voltage (I–V) relationships at the NDR region were seriously affected by the thermal process according to the level of applied CC. The co-existence of RS and NDR was possibly caused by defects during migration, such as oxygen vacancies and interstitial iron ions, which were formed in the α-Fe2O3 nanorod film. This work provided information on the ongoing effort toward developing novel electrical features of advanced transition metal oxide devices.
分类: 核科学技术 >> 核科学与技术 提交时间: 2024-05-12
摘要: 在物理试验中准确测量控制棒价值对于反应堆安全运行有着非常重要的意义。开展基于六角形几何的多群时空动力学计算方法研究,基于此,开展适用于六角形几何的先进动态刻棒方法研究。该方法适用范围广,测量精度高且测量过程快。利用田湾VVER动态刻棒试验数据对该方法进行了验证,结果表明基于该方法所测量的控制棒价值与理论值偏差在10%以内,计算精度较高,且该方法计算时间较短,计算效率高。