HTR－10小盘管螺旋管圈高压汽水两相流动摩擦阻力特性的研究

在压力ｐ＝４－１４ＭＰａ，质量流密度Ｇ＝４００－２０００ｋｇ／ｍ２·ｓ，内壁热流密度ｑ＝０－７５０ｋｗ／ｍ２的参数范围内，进行了螺旋管内高压汽水两相流动磨擦阻力的试验研究。螺旋管分水平放置和垂直放置；有电加热和绝热两种；管内径是１２ｍｍ和１０ｍｍ，螺旋直径均为１１５ｍｍ。另外还有一受热水平直管用来进行比较。通过理论分析和试验数据回归得到了一个经验关系式，用来计算水平或垂直放置的螺旋管内的汽水两相磨擦阻力。     

Analysis of the coil centrifugal force field in countercurrent chromatography

1 INTRODUCTIONCountercurrent chromatography(CCC)is a true liquid-liquid partition chromatographywhich totally eliminates the use of a solid support.Being a support-free system,themethod offers a number of advantages over other chromatographic methods byminimizing problems arising from the use of solid supports such as adsorptive loss andinactivation of samples,tailing of solute peaks,contamination,etc.In practice,CCCprovides its greatest advantage in preparative-scale separations where high-performanceliquid chromatography(HPLC)suffers loss of partition efficiency and high expenditure     

量子拍频三能级原子的偶极压缩效应

本文讨论Ｖ型量子拍频三能级原子体系与单模光场相互作用时原子的动力学行为，并研究了原子的偶极压缩效应。     

Biplanar gradient coil design by simulated annealing

Simulated annealing has been applied to the design of biplanar gradient coils for use in NMR microscopy. This method allows a variety of coil parameters to be considered, such as homogeneity over a specified region of interest (ROI), power dissipation, and efficiency. Chosen parameters are represented in an overall figure of merit which is then minimized by the simulated annealing approach. Unlike most analytical techniques which rely on the use of the stream function, with this technique the coil properties are calculated directly from the wire positions, so there is no stage of approximation between current density and the actual coil design. Using this technique, we have designed biplanar x and z gradient coils for use in an 11.7-T NMR microscope. In each case, the coils were composed of straight wire units. The plane spacing was set at 10 mm and the ROI was a central cube of side 6 mm. Starting from a design generated using the target field approach, simulated annealing was applied with the aim of minimizing the ratio of power dissipation per unit current to the square root of coil efficiency while maintaining adequate gradient homogeneity. The efficiency and power dissipation per unit current of the resulting x and z coils were 117 mT m^–1 A^–1 and 0.1 W A^–2, and 99 mT m^–1 A^–1 and 0.4 W A^–2, respectively.     

减压炉汽化段炉管的工艺设计中PRO/Ⅱ软件的应用

简述了具有相变的减压炉汽化段炉管设计的工艺特点和计算方法，介绍了用PRO／Ⅱ的“PIPE”单元计算减压护汽化段炉管的方法，并给出了计算实例。     

虚火花放电产生的强流脉冲电子束流强度测量

介绍了用于最近成功运转的高功率，强流密度，低发射度，高亮度虚火花电子束源的强流测量方法──自积分线圈测量法。给出该线圈的实用化设计及其标定方法。实验表明，这种线圈在强流环境里特性很好，虚火花电子束的束质量比冷阴极电子束好得多。     

Quench detection method without a central voltage tap by calculating active power

In this paper, we present an electric quench detection method without a central voltage tap which may cause the short-circuit of the lead-wires from the voltage taps in the quench detection of a large AC superconducting coil. In this method, an inductive voltage detection coil is used instead of the central voltage tap. The inductive voltage detection coil is electrically insulated from a superconducting coil and therefore the lead-wires do not break down. Through the quench detection tests for a Bi-2223/Ag HTS coil, we show the feasibility of the proposed method for detecting the quench of the large AC superconducting coil.     

一种用于微带半波振子天线的新型BALUN

通过将常规的空气板线BALUN微带化，从而建立一种新型微带BALUN。该BALUN引入一个并联谐振电路，可以有效补偿半波振子的串联电抗而实现微带半波振子带宽的最大化。采用此种BALUN设计制作了一个L波段微带偶极子天线单元。测试结果表明：该半波振子天线在21．8％的带宽内驻波比优于1．18，带内交叉极化优于一21dB，接近理论最大设计带宽。     

Experimental study on steam-water two-phase flow frictional pressure drops in helical coils

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基于四参数仿射模型的频域运动估计技术

仿射模型能比块平移模型更好地拟合真实运动场景,但待解的参数也相应地增加了.基于梯度的搜索算法在高阶问题中存在局部极小和收敛速度的缺陷,基于Hough变换和Gabor滤波等的变换域方法同样存在运算量的问题,影响了仿射模型在实时运动估计中的应用.传统的相位相关法仅利用了傅氏频谱的相位信息求解块平移而未利用频谱的幅值特性.本文通过对仿射运动场频域特性的分析,将仿射模型的线性项和平移项解耦,结合频谱的幅值特性和相位特性在频率域内求解仿射运动参数.实验结果表明该算法在运算量增加不大的情况下运动估计效果得到明显改善.