三相异步电动机运行指标的分析

利用电机学理论分析了影响电机起动转矩、起动电流、最大转矩和最小转矩的因素。     

Study on Adsorption Behavior of Rare Earth Complexes on Nanometer-Size Titanium Dioxide with ICP-AES

Inrecentyears ,rareearthelements (REEs)havebeenwidelyusedinfunctionalmaterials ,cata lystsandotherproductsinindustry ,diagnosisreagentsofmagneticresonanceimaging (MRI)inmedicineandsomefertilizersinagricultureespeciallyinChina .However,asaresultoftheirusage ,moreandmoreREEsaregettingintotheenvironment,andalsointohumanbodyviafoodchain[1,2 ] .Itisnotclearwhetherrareearthelementsareessentialforman ,soitisveryurgenttostudythebiologicaleffectofrareearthelementsinhumanhealthandenvironment .Inthes…     

F-X域粘弹性波动方程保幅偏移

提出了一种利用粘弹性声波波动方程进行偏移的新方法。其基本思路是,修改成像条件,使修改后的成像方程中考虑振幅补偿,然后利用粘弹性、单程波动方程在F-X域对震源和接收点波场进行延拓,进而完成散射、透射等补偿。理论数据处理和实际地震资料处理表明,该方法理论基础可靠,处理效果明显,能较好地解决实际地质问题。     

含钡合金的生产及其对钢液脱氧行为的研究

介绍了含钡合金的生产状况。在MoSi2炉上对钢管钢进行了含钡合金脱氧行为的研究，然后在150tLF／VD精炼设备上进行了使用含钡合金的工业试验。研究中主要选取SiAlBa、SiCaBa、SiAlBaCa、SiAlBaCaSr及用于钙处理的SiCa包芯线，并选用Al和FeSiAl作为对比脱氧剂，分别考察了实验室条件下和实际生产过程中，采用钡系合金对钢液脱氧的全氧含量，脱氧产物的分布、尺寸和形貌，探讨了钡系合金脱氧和对夹杂物的变质作用的机理。     

"信号调制法"研究电子诱导脱附--基本原理及误差分析

电子诱导脱附是近年来在真空科学与表面科学领域内的热门研究课题。它不仅作为研究和探讨原子激发过程以及电子能量传输机制的有效手段,而且已经逐渐成为获取表面和界面结构、状态等信息的有效方法。“信号调制法”是利用脉冲电流能量调制的电子探束取代传统的直流电子探束,并通过测量电子诱导脱附产物引起的压强变化量,来研究电子诱导脱附的新方法。本文系统地介绍了该方法的基本原理,并从理论上对该方法带来的测量误差进行了分析。     

低温等离子体对血管内金属支架的表面改性

生物材料用于人体必须要具备生物相容性。尤其是与血液相接触的材料如血管内支架必须要具备血液相容性。材料的表面特性直接影响血液系统中是否会出现血栓。本文针对金属血管内支架的表面特性、与血液的界面反应以及用于提高血液相容性的低温等离子表面改性进行了简要综述     

吉林闹枝金矿床黄铁矿的标型特征研究

从成因矿物学及找矿矿物学的观点出发，系统地研究了闹枝金矿床黄铁矿的形态、粒度、化学成分、热电性、硫同位素方面的标型特征，为矿床的成因研究和深部远景评价提供了矿物学依据。     

A novel optical burst switching scheme—logical cascaded private subnet with start wavelength assignment policy

Many recent studies have convincingly demonstrated that network traffic exhibits a noticeable self-similar nature, which has a considerable impact on network performance, and most studies of optical burst switching (OBS) networks are under a fundamental assumption that full wavelength conversion is available throughout the network. In practice, however, economic and technical considerations are likely to dictate a more limited and sparse deployment of wavelength converters in the optical network. Therefore, we present a novel scheme for OBS networks, called logical cascaded private subnet (LCPN) with start wavelength assignment policy. We define the concept of canoe relative to cluster in self-similar traffic, and introduce a new device named payload segregator at the edge node as a gateway to the core node in OBS Networks. According to the changes in the edge node framework, we put forward the concept of cluster private subnet and canoe private subnet in the core node correspondingly. A new start wavelength assignment policy is proposed for the absence of (full) wavelength conversion capabilities in the core node of OBS Networks. The performance study indicates that, our new scheme is robust under self-similar traffic and wavelength continuity constraint.     

First Harmonic (2f) Characterisation of Resonant Frequency and Q-Factor of Micromechanical Transducers

In this paper, the response to the first harmonic component (2f) of the electrostatic force in single terminal driven electrostatic comb-drive and parallel-plate drive was used as a signal to extract device parameters, namely, the Q-factor and resonant frequency instead of the fundamental (1f) resonance response. It is shown that the difficulty in motional measurement due to electrical cross-talk (parasitics) using 1f measurement can be overcome with a higher signal-to-noise ratio of the 2f signal. Both atmospheric (low-Q) and reduced pressure environment were investigated using off-chip electronics and lock-in amplifier. The measurements were done on the electrostatic comb-drive and capacitive parallel plate sensing plates that form the two core modules of a yaw rate sensor (dual-axis resonator). The effects of AC and DC bias voltages on the measured response have been investigated. Experimental amplitude and phase response data have been analysed using the Lorentzian curve-fit, Resonance Curve Area (RCA) method, the half-power bandwidth method (3 dB) and the Nyquist plot for data fitting and determination of the Q-factor and resonance frequency.     

DSP在声频谱测井仪器中的应用

声频谱仪器是一种新型的数控全波列测井仪，采用DSP作为它的控制核心器件，以便实现对整个仪器的工作状态、数据采集及传输的控制，是声频谱测井仪器的核心部分。文章主要介绍DSP的芯片结构和性能、ADSP-2101在声频谱仪器控制系统中的功能及实现、声频谱仪器现场采集的接收全波列波形和结论。