基于电/磁转换的海洋电场检测方法

传统的直接电测量方法受1/f噪声限制,在低频处信号与噪声发生混叠,难以实现高水平低噪声测量。该文提出一种基于电/磁转换的海洋电场低噪声检测方法,将电信号转化为磁信号,通过微机械的方法将磁信号调制到高频,有效避开低频1/f噪声影响。设计一种实现电/磁转换功能的微机械结构,利用TMR电阻构成惠斯通电桥测量磁信号,实现海洋电场的高水平低噪声检测。仿真与实验结果在1 Hz处噪声分别达到1.16 nV/(Hz)~(1/2)和1.41 nV/(Hz)~(1/2),优于传统电测量方案的噪声水平,验证该方法的有效性。     

大功率声电转换材料的研究及其应用

本文简要叙述了大功率声电转换材料在声学及电子工程领域中的意义和作用，论述研制和开发新型、高性能大功率声电转换材料是大功率声电转换器件研制和开发工作的需要，还介绍了作者研制的系列大功率压电陶瓷Ｆ１－ＰＺＴ、Ｆ２－ＰＺＴ、ＦＤ３－ＰＺＴ及ＦＤ４－ＰＺＴ的有关情况。     

Zn-Se/不锈钢薄膜的电沉积及其应用研究

研究了Zn-Se/不锈钢薄膜的电沉积工艺条件及其在染料废水处理中的应用.讨论了电流密度、初始浓度比(c(ZnSO4):c(Na2SeO2))、pH值、柠檬酸钠加入量、电沉积时间、电沉积温度以及超声功率对镀层的影响.经扫描电镜及能谱仪分析测试表明,在电流密度为3.8mA/cm2、初始浓度比为250:1、pH=2.9、柠檬酸钠加入量为14.71g、电沉积时间为7min、电沉积温度为55℃、超声功率为160W条件下制备出的Zn-Se/不锈钢薄膜,其表面结晶致密、均匀,Zn与se的化学计量比为1:1.25.用所制备的薄膜材料作阴极,采用电化学复合技术处理罗丹明B模拟染料废水,可使模拟废水的脱色率接近99%,COD去除率接近90%.     

碳气凝胶的制备及其电除盐性能的研究

在常压条件下通过溶胶-凝胶法和碳化、活化工艺制备碳气凝胶材料.用SEM和BET比表面积测量等手段对材料的表面形貌和微观结构进行分析表征,通过循环伏安法对材料的电化学性能进行研究.联系材料的微观结构和电化学性能,对碳气凝胶的电除盐过程和除盐机理进行了研究和分析,发现碳气凝胶是一种具有很大应用潜力的多孔电极吸附材料.     

电转气成本特性对电–气–热综合系统调度的影响

电转气技术是一种有前景的连接电网与燃气网的方法,将广泛应用于电-气-热综合能源系统中,以提高其运行灵活性.然而,电转气较高的运行成本将影响其在综合能源系统中的应用.该文提出计及电转气成本和风电利用率的电-气-热综合能源系统调度模型,分析电转气成本特性对综合能源系统调度的影响.首先,介绍包含电转气的电-气-热综合能源系统...     

复合电沉积制备SnO2/TiO2薄膜及其光电催化性能

为了寻求廉价、高效和稳定的光催化剂,用复合电沉积技术在紫铜片上制备了Sn/TiO2薄膜,经300℃热氧化使之形成SnO2/TiO2复合电极.利用SEM,XRD对薄膜进行了表征,以甲基橙为模型化合物,对复合电极的光催化和光电催化性能进行了测定.研究表明:该薄膜由0.3~1μm的颗粒构成,每个颗粒又由纳米晶粒形成;电极具有多孔结构,膜中的SnO2以两种不同的晶体结构存在;在薄膜质量相等的情况下,SnO2/TiO2薄膜的光催化活性是纯TiO2粒子膜的2.87倍;外加一定偏压下,其催化性能大幅度提高.     

介电/半导体功能集成薄膜的制备和特性调控

介电/半导体功能集成薄膜,主要是指将具有电、磁、声、光、热等功能特性的介电功能材料(主要是氧化物类介电功能材料)与硅、砷化镓或氮化镓等典型半导体类功能材料,以单层薄膜或多层薄膜的形式生长(甚至外延生长)在一起而形成的人工新材料,这类新材料有可能具有多功能一体化和功能特性之间的相互调制及耦合等特点,可望在新型电子和光电子器件中获得应用.介绍了介电/半导体功能集成薄膜产生的背景;从集成铁电薄膜与器件、HK/半导体集成薄膜与器件以及极性氧化物/GaN功能集成薄膜与器件等3个方面,分别介绍了介电/半导体功能集成薄膜的应用;概括介绍了介电/半导体功能集成薄膜的制备方法及特性调控.     

高精度的轴角/数字转换系统

目前,在许多火控系统中,还有不少的系统仍采用自整角机作为目标测定器,其输出为模拟信号,为了提高火控系统的性能,计算机理所当然地被引入到其中,而这就需进行轴角/数字转换,本文叙述了一种转换精度高,速度快的轴角/数字转换系统。     

SnO2/Fe2O3双层薄膜的界面结构及其对气敏特性的影响

本文给出用等离子化学气相沉积 (PCVD)技术制备的SnO2 /Fe2 O3 双层薄膜结构的俄歇谱 (AES)剖面分析、透射电镜 (TEM)断面形貌和扫描电镜 (SEM)表面形貌的实验研究结果。AES剖面分析和TEM断面形貌图显示在SnO2 与Fe2 O3 界面区有一个约 35nm厚的过渡层存在 ,其质地松散。实验还发现这个界面过渡层的存在缓解了层间应力 ,增强了SnO2 薄膜的附着力 ,对该双层膜的气敏特性有明显的控制作用 ;但当SnO2 层厚大于 2 70nm时 ,其控制作用几乎完全消失     

Solute-homogenization model and its experimental verification in Mg-Gd-based alloys

Composition homogenization in solid solution is important for industrial alloys. In the present work, a solute homogenization model is proposed based on the chemical short-range-order tendency in Mg-Gd-based alloys. After a calculation using the cluster-plus-glue-atom model, the stable Mg-Gd structural unit is derived, [Gd-Mg₁₂]Mg₆, where one solute Gd is nearest-neighbored with twelve Mg atoms to form the characteristic hcp cluster [Gd-Mg₁₂] and this cluster is matched with six Mg glue atoms. Such a local unit is then mixed with [Mg-Mg₁₂]Mg₃, the stable unit for pure Mg. Assuming that the Gd-containing units are arranged in fcc- or bcc-like lattice points and the Mg units in their octahedral interstices, three proportions between the two units are obtained, 1:1, 2:3, and 1:3, which constitute three solute homogenization modes. The prevailing Mg-Gd-based alloys are consequently classified into three groups, respectively exemplified by GW103 K (Mg-10Gd-3Y-0.4Zr, wt%), GW83 K (Mg-8Gd-3Y-0.4Zr), and GW63 K (Mg-6Gd-3Y-0.4Zr). Mg-Gd-Y-Zr alloys were designed following the model (where Y and Zr were also added in substitution for Gd) and prepared by permanent-mould casting. According to their mechanical properties, the 1:3 alloy (Mg-5.9Gd-1.6Y-0.4Zr) shows the best comprehensive properties (ultimate tensile strength 305 MPa, yield strength 186 MPa, elongation 9.0%) in solution plus ageing state.     

A model of a magnetomodulation converter

A model of a magnetomodulation converter in which the remagnetization of the sensitive elements is approximated by a piecewise-linear function is proposed. Translated from Izmeritel’naya Tekhnika, No. 1, pp. 47–51, January, 2009.     

A new model of shear creep and its experimental verification

Mechanics of Time-Dependent Materials - Creep exerts a significant role in rock engineering safety. In engineering practice, it is helpful to develop a mathematical model representing rock creep...     

Two-dimensional temperature field of a semiconductor thermoelectric converter

Analytic relations are obtained for constructing the two-dimensional temperature field of a semiconductor thermoelectric converter operating in the steady-state regime.     

Numerical and experimental verification of a damping model used in DEM

This paper presents a study on the damping ratio \(({\upbeta })\) used in discrete element simulations. Physical experiments are performed by dropping particles from a predetermined height. Two kinds of granular particles, aluminum and steel spheres, are used. The size of these particles are the same. The process of particle depositing under gravity is simulated using the discrete element method. The experimental observation is compared with the numerical result to identify the appropriate \({\upbeta }\). The result indicates that the appropriate damping ratio used in discrete element simulations is between 0.2 and 0.3 %. Various \({\upbeta }\) are then used in the numerical simulations to study the effect of \({\upbeta }\) on the dropping process. The final height of the sample relates to \({\upbeta }\) and the drop height. The effect of \({\upbeta }\) is more profound for small drop height. For greater drop height, the effect of \({\upbeta }\) is negligible.     

快速以太网光纤收发器系统设计

为了便于用户接入网的升级,又可以保护原有的铜缆投资,论文设计了一种带宽充足,性能稳定、高可靠性、低价位的多模快速以太网光纤收发器,该收发器主要由RJ45电接口模块、光电介质转换芯片AL210和光收发一体化模块HFBR - 5105组成.论文介绍了该收发器的工作原理,光电介质转换芯片AL210,光收发一体化模块HFBR - 5105,详细说明了设计方法,并给出了设计的具体原理图.     

Physical model of an integrating converter

Results are presented of theoretical investigations of a thermal converter model in a nonstationary operating mode.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 55, No. 6, pp. 965–970, December, 1988.