First-principles study on the electronic and optical properties of F- and Nb-doped anatase TiO2

We present a comparative study on the electronic and optical properties of Nb- and F- doped anatase TiO₂ by first-principles calculations based on the density functional theory (DFT). Although both TiO₂:Nb and TiO₂:F have a similar band structure, the effective mass of TiO₂:F is larger than that of TiO₂:Nb, and the carriers density in the former is lower than that in the latter, indicating that TiO₂:Nb has better electronic conductivity than TiO₂:F. The interaction between photons and electrons in TiO₂:F is much stronger than that in TiO₂:Nb, resulting in increased photon absorption and reduced transmittance, especially in the visible and near-infrared regions. The results demonstrate that TiO₂:F is not suitable for transparent conductive oxide applications.     

γ（fcc）→α（bcc）马氏体相变表面浮凸的AFM观察与定量分析

利用原子力显微镜（AFM）及扫描电镜（SEM）观察并定量分析了γ(fcc)→α（bcc)马氏体相变的表面浮凸。结果表明：{259}f马氏体表面浮凸为双倾动、帐篷（∧）型，{557}f马氏体的表达浮凸为“孤立岛状”浮凸群，{225}f马氏体表面浮凸为具有层状结构的“三角形”浮凸群；{259}f马氏体表面浮凸的宽度、高度及浮凸角度均大于{225}f马氏体“三角形”浮凸群，{557}f马氏体表面浮凸群的高度最小，其浮凸角也最小。     

套管车丝机锁紧缸杆断裂的原因分析及解决方法

0　概　述我公司从美国 PMC公司引进的套管、接箍两条生产线是 2 0世纪 90年代世界先进的生产线 ,471型 CNC套管车丝机是其中最关键设备。471型 CNC套管车丝机有四组卡盘 ,距离车丝机由近及远依次为 :定位卡盘、机内浮动卡盘、机外浮动卡盘、固定卡盘。全部卡盘由液压驱动。装卡过程为 :管子传递到加工工位→固定卡盘卡紧同时定位卡盘定位卡紧→两浮动卡盘卡紧→定位卡盘松开→管端加工螺纹→三卡盘同时打开。CNC套管车丝机的装卡装置 ,使钢管中心和车丝机主轴中心完全重合 ,克服了由于钢管管径和直线度误差造成的定位误差。这种巧妙的…     

单片机与PC机三线制高速串行通讯

分析了单片机与PC机串行通讯波特率误差来源，采取选择单片机适配晶振频率的方法，解决了串行通讯高速度与可靠性之间矛盾，可实现串行数据高速无误差传输，在多项实际应用中取得满意的效果。文中给出了硬件接口和程序设置。     

一种新型萃取装置及其在水样挥发酚测定中的应用

本文介绍一种新型萃取装置,由磁力搅拌器、三角烧瓶和经改造的活塞组成。此装置已用于挥发酚的测定中。大量实验数据表明,该装置优于常规分液漏斗,克服了使用分液漏斗中常见的易漏、重现性差、工作强度大等缺点。其准确度,重现性,工作曲线相关性均较好,是一种可以取代分液漏斗,用于各类常规分析的理想玻璃仪器。     

Facile coordinating decoration of salophen Al on graphene nanosheet: Salophen Al complex functionalized graphene nanocomposite with electrochemical properties

Salophen Al complex functionalized graphene (SCFG) nanocomposite was synthesized by simple coordination of phenol functionalized graphene (PFG) and as-prepared salophen Al complex. This process is facile, convenient and high efficient. We also investigated the structure, optical properties and electrochemical properties of the obtained SCFG composites. The results showed that salophen Al conjugated and incorporated onto the graphene sheet surface and the composites maintained the micro-structure of graphene sheets without agglomeration. The photoluminescence of salophen Al was completely quenched by graphene, due to the charge transfer between the salophen Al and the graphene nanosheets. Moreover, a significant electrochemical signal emerged on the SCFG modified electrodes compared with those of the graphene sheets or salophen Al complex. Owing to preliminary results of the excellent electrochemical property, SCFG nanocomposite is a promising electrochemical redox probe material.     

3D navicular ceria micro/nanocomposite structure with multi-layered arrangement and its application in CO oxidation

In this work, novel three-dimensional (3D) navicular ceria micro/nanocomposite architecture with multi-layered structure was synthesized for the first time via solution reaction followed by a simple hydrothermal treatment in the presence of lysozyme. During the synthesis procedure, a 3D navicular ceria precursor (Ce₂O(CO₃)₂·H₂O) with multi-layered structure was obtained after hydrothermal treatment at 100 °C for 10 h. Ceria with the same morphology can be obtained after thermal decomposition of this Ce₂O(CO₃)₂·H₂O precursor. Structural properties of the products were characterized by XRD, TG-DTA, FT-IR, SEM, TEM, and N₂-sorption techniques. Then a possible layer-by-layer electrostatic self-assembled growth mechanism was proposed for the formation of this 3D navicular architecture based on the experimental results and detail analysis of the evolution process of ceria precursors. Furthermore, a mold reaction of the catalytic oxidation of CO was conducted on the as-obtained CeO₂ and gold supported catalyst, both showed excellent activity and durability for CO conversion.     

一种基于邻居节点间相互影响和改进概率的社交网络信息传播模型

目前网络传播动力学的研究焦点之一是以经典的传染病动力学模型为基础,来研究特定网络的信息传播规律。本文针对社交网络中信息传播的特点,在传统的SIR模型基础上,加入新的一类假免疫节点,建立了SDIR模型。并考虑到邻居节点间的相互影响,定义了三个传播概率函数,对SDIR模型做了改进。通过对比不同条件下信息传播的过程,实验证明了信息不能覆盖全网络,Twitter比新浪微博有更好的信息传播效率的推测,并发现初始传播概率会对信息传播有重要影响。     

铝电解槽控机可靠性探讨

本文分析了影响大型预焙电解槽自控系统槽控机可靠性的因素，提出了提高槽控机系统可靠性的思想，重点论述了电解槽控机软件保护技术，硬件保护技术和抗干扰技术。通过这些技术的研究应用证明，槽控机的可靠性得到大幅提高。     

1993～2005年秦山核电公司外照射个人剂量监测

介绍了秦山核电公司1993年～2005年外照射个人剂量监测工作的开展情况。着重从热释光个人剂量计的使用、监测方法及数据处理、质量保证和剂量数据评价等方面进行描述，指出存在问题，提出对今后个人剂量监测工作改进的一些想法和建议。