查询词典 alternating current

Conversion of alternating to unidirectional current.

直流电和交流电同步转换的机器。

In the experimental processes, the degenerately p-doped silicon wafers with 100 nm silicon oxide were used as the back gate; palladium metal electrodes were formed by photolithography combined with lift-off technique, and finally deposited and aligned CNTs on the predefined electrode pairs to complete devices fabrication by using alternating current dielectrophoresis.

在实验制作方面，我们以退化型之重掺杂矽基材作为背闸极，基材上方长出100nm之氧化矽绝缘层，配合微影制程定义钯电极於介电层上，再利用介电泳力将奈米碳管接合至电极上方，完成奈米碳管电子元件之制作。

This procuct is even a savior for the ajumping-off which use alternating current disconvenient .

本产品是出差、旅行、在校学生、上班一族和跑业务者的好伴侣，对边远地区交流电充电不方便的地方本产品更是手机等的一个大救星。

The influence of alternating current magnetic fields on the solidification structure of hypoeutectic Al-7%Si alloy was studied.

中文摘要：研究了在交流磁场下凝固的Al-7%Si合金晶内Si溶质元素含量及凝固组织的变化。

To solve the problem of interference between main arc and pilot arc and improve the stability of main arc, all possible ways such as adopting noncontinuous or alternating pilot arc or making main arc and pilot arc have different current passages and detailed measures are proposed.

论述了等离子弧焊中维弧的存在形式及其对主弧的稳定机理，提出了解决主、维弧相互干涉的各种可能途径如采用断续维弧、交流维弧或使主、维弧具有不同通道及从维弧形态等方面提高主弧稳定性的具体措施。

At first, this paper gives the brief introduction of the history and present status of accelerometer and its testing technology, the working principium and math model of the liquid floated pendu-lous accelerometer, and then, decides the binary width pulse force retrim loop as the design proposal of testing system, researches the transfer function of every part in the system emphasizly, analyses the stability of the whole accelerometer testing system from the angle of control theoretics by the open loop transfer function of system, and designed the correcting net, analyses the basal problems such as resolution, sampling restraint, precision and so on, designs the hardware testing circuits such as preamplification, band-pass filter, alternating amplifier, phase sensitive demodulatorn, pulse-width modulation, frequency scale circuit, moment current generator. Finally, using the graphics program language LabV-IEW which is designed for testing field especially by NI accomplishes the solfware design of testing system,realized the testing functions.

首先对加速度计及其测试技术的发展历史和现状，液浮摆式加速度计的工作原理和数学模型等作了简要的介绍，然后确定了以二元调宽脉冲再平衡测试回路为设计方案，并从控制理论的角度进行了分析，着重研究了系统中各部分的传递函数，利用系统开环传递函数分析了系统的稳定性，同时设计了系统的校正网络；分析了二元调宽脉冲再平衡测试回路的分辨率、采样约束以及测试精度等基本问题，并按照系统分析的结果设计了包括前置放大、带通滤波、交流放大、相敏解调、脉宽调制、频标电路以及力矩电流发生器等测试系统各部分硬件电路，验证了电路的正确性，最后按照测试系统的要求，采用了美国NI公司专为测试领域所开发的虚拟仪器工具——LabVIEW作为测试软件开发工具，利用该图形化编程语言完成了测试系统软件部分的设计，实现了测试功能。

In a normal alternating current power system, the voltage varies sinusoidally at a specific frequency, usually 50 or 60 hertz.

在一个正常的交流电力系统，正弦电压变化在特定的频率，通常是50或60赫兹。

The method by drying/adsorption was used to prepare DNA adsorptively modified electrodes, and thus-resulting DNA-modified electrodes were electrochemically and spectroscopically characterized, including cyclic voltammetry, scanning tunneling microscopy, Raman spectroscopy, in-situ UV/Vis reflection spectroscopy, X-ray photoelectron spectroscopy, and alternating current impedance. Some information about the state of DNA immobilized on electrode surfaces was obtained.

鉴于此，本论文工作首先利用简便的干燥吸附法制备获得DNA吸附修饰电极，采用电化学方法及多种谱学仪器方法如STM，XPS，Raman，交流阻抗，UV-Vis现场光谱等对DNA修饰电极进行了表征，获得了有关DNA在电极表面状态等有价值的信息；又采用自组装单分子层修饰技术，制备出DNA共价键合修饰SAM/电极，并对制备条件进行了优化，利用XPS及电化学方法对修饰电极进行了表征。

The anisotropic bonded NdFeB magnets were prepared by die-upsetting process and the effect of surface residual magnetization of anisotropic bonded magnets which were demagnetized by alternating current demagnetization and heat demagnetization process on the quantity of magnetic powder attracted on the surface was investigated.

采用模压成型方法制备各向异性粘结NdFeB 磁体，并研究了其经交流退磁及热退磁后磁体的表面剩磁大小对磁粉吸附程度的影响。

This structure applies non-controlled rectifier, boost chopper and SPWM inverter chopper to convert the electric energy dynamited by electrical machine into alternating current which can be accessed to the constant frequency and voltage of electricity grid.

详细介绍了直驱型风力风电系统的组成结构及其变流系统的控制原理，给出了一种在考虑现有开关器件功率水平的情况下符合大功率直驱并网型风力发电机组要求的变流电路拓扑结构，并给出了相应的主要部分的具体应用电路。

Who? I never heard of him, Paul said, before asking teammate James Posey if he had heard of him.

赛后，科比说，他一直都是一名非常出色的射手，今天他打得很棒。

When I joined the company, I rotated around the different sections.

我加入这个公司时，轮换过几个不同的部门。