Measurement of 8～25keV electron impact K－shell ionization cross sections of Cu and Co elements

Ｍｅａｓｕｒｅｍｅｎｔｏｆ８～２５ｋｅＶｅｌｅｃｔｒｏｎｉｍｐａｃｔＫ－ｓｈｅｌｌｉｏｎｉｚａｔｉｏｎｃｒｏｓｓｓｅｃｔｉｏｎｓｏｆＣｕａｎｄＣｏｅｌｅｍｅｎｔｓＡｎＺｈｕ（安竹），ＬｉＴａｉ－Ｈｕａ（李泰华），ＷａｎｇＬｉａｎｇ－Ｍｉｎｇ（王良明）...     

In~+离子注入蓝宝石(α-A1_2O_3单晶)的表面改性研究

研究了＜０００１＜和＜１２１０＞晶向蓝宝石（α－Ａｌ２Ｏ３单晶）在注入３６０ｋｅＶ．１×１０￣１６ｃｍ￣－２或１００ｋｅＶ、６×１０￣１６ｃｍ￣－２的Ｉｎ￣＋后产生的损伤、注入层的性能变化和退火行为。实验结果表明，退火过程中损伤的恢复和Ｉｎ的分布与退火气氛有关：在１００ｋｅＶ、６×１０￣１６ｃｍ￣－２的Ｉｎ￣＋注入时，注入层电阻率降低了１０个量级，大小为６．８×１０￣３·ｃｍ，表面损伤层的显微硬度提高了９２％；在３６０ｋｅＶ，１×１０￣１６ｃｍ￣－２的Ｉｎ＋注入时，其表面损伤层的显微硬度提高了４５％，在空气中不同温度下退火后，其显微硬度的变化和损伤的变化具有相同的规律。     

低能离子束辐照氨基酸结构变化的傅立叶变换红外光谱法研究

利用傅立叶变换红外光谱（ＦＴＩＲ）法研究了３０ｋｅＶ的Ｎ＾＋离子束辐照引起氨基酸结构的变化。结果表明：经相同剂量Ｎ＾＋离子束辐照后,天冬氨酸（Ａｓｐ）和苯丙氨酸（Ｐｈｅ）的基团有相似的变化规律,即羧酸根离子（ＣＯＯ＾－）的ｖＣ＝Ｏ伸缩振动（分别为１６４６ｃｍ＾－１和１６２６ｃｍ＾－１）均增强,ＮＨ３＾＋的谱峰（分别主要为１５１７ｃｍ＾－１和１５６０ｃｍ＾－１）强度均减弱。Ｐｈｅ较Ａｓｐ中的基因强度     

In^＋离子注入蓝宝石（α—Al2O3单晶）的表面改性研究

研究了〈０００１〉和〈１＾－２１０〉晶向蓝宝石（α－Ａｌ２Ｏ３单昌）在注入３６０ｋｅＶ、１×１０＾１６ｃｍ＾－２或１００ｋｅＶ、６×１０＾１６ｃｍ＾－１的Ｉｎ＾＋后产生的损伤、注入层的性能变化和退火行为。实验结果表明，退火过程中损伤的恢复和Ｉｎ的分布与退火气氛有关：在１００ｋｅＶ、６×１０＾１６ｃｍ＾－２的Ｉｎ＾＋注入时，注入层电阻率降低了１０个量级，大小为６．８×１０＾３Ω·ｃｍ，表面损伤层的显     

锗γ谱仪^110mAg符合相加修正因子测量

通过在ＨＰＧｅ探测器表面及距探头２８ｃｍ处分别测量形状相同的＾１１０ｍＡｇ（６５７．８ｋｅＶ）和＾１３７Ｃｓ（６６１．６ｋｅＶ）体源的全能峰妆计数率,可在避开源活度,发射几度和自吸收修正等条件下,测得在探测器表面测量＾１１０ｍＡｇ６５７．８ｋｅＶγ射线的符合相加修正因子Ｆ０;本文介绍了此测量方法的原理和测量结果。     

碘化汞半导体探测器的能量分辨率

介绍了ＨｇＩ２晶体的生长方法及探测器制备技术，讨论了ＨｇＩ２半导体探测器的能量分辨率，测得ＨｇＩ２探测器在室温玻地＾５５Ｆｅ５．９ｋｅＶ和＾２４１Ａｍ５９．５ｋｅＶＡ射线的能量分辨率分别为１．３ｋｅＶ和３．４ｋｅＶ。     

高剂量铂和钇离子注入Al2O3单晶的表面改性

研究了〈０００１〉和〈１２↑－１０〉晶向α－Ａｌ２Ｏ３单晶在高剂量的Ｙ、Ｐｔ离子注入后产生的损伤,注入层的性能变化和退火行为。实验结果表明,在室温,１７１ｋｅＶ、１×１０＾１７／ｃｍ＾２Ｙ离子注入的〈１２↑－１０〉α－Ａｌ２Ｏ３单晶的表面层约有１３９ｎｍ厚被无定形化。而１５８ｋｅＶ、９×１０＾１７／ｃｍ＾２Ｐｔ离子注入的〈０００１〉α－Ａｌ２Ｏ３单晶的表面层不产生无定形,且实际离子注入进衬底的剂量     

Ar离子辐照的非晶态合金表面发泡扫描电镜观测

１５０、１９５和３００ｋｅＶＡｒ离子在室温下辐照非晶态合金Ｃｏ７０．２Ｆｅ３． ９Ｎｄ３．９Ｓｉ１４Ｂ８和Ｃｏ６６Ｆｅ４．５Ｖ２．２５Ｎｉ２．２５Ｓｉ１０Ｂ１５，扫描电镜在一定的辐照剂量范围观测到了表面发泡形成，发泡形成的临界剂量和直径随离能量增加而增加。Ａｒ离子能量高于１９５ｋｅＶ时，发泡和发泡破裂是主要的表面损伤现象，而在１５０ｋｅＶＡｒ离子辐照下，未观测到发泡破裂。     

堆芯功率分布重构方法分析

本文介绍了堆芯功率分布重构方法中传统的两种方法：权重系数法及多项式展开法。用堆芯计算程序SMART构造测量和预测状态分布,分别采用权重系数法和多项式展开法进行径向功率重构。计算结果显示,在径向重构中多项式展开法对瞬态及局部下的重构效果并不佳,而权重系数法则能部分重构堆芯局部各处的偏差分布。在稳态下,两种重构算法各有优点。     

峰面积比法测量绝对热中子注量率

介绍了利用γ谱仪测量绝对中子注量率的方法。在已知中子场中照射金（Ａｕ）箔和铕（Ｅｕ）箔，利用γ谱仪分别测量＾１９８Ａｕ和＾１５２Ｅｕ的４１１ｋｅＶγ峰面积，根据两者的峰面积之比和已知中子场的约对中子注量率，求得＾１５２Ｅｕ的４１１ｋｅＶγ峰面积对应的中子注量率。在待测中子场中，照射金箔，利用γ谱仪测量其４１１ｋｅＶγ峰面积和刻度过的＾１５２Ｅｕ的４１１ｋｅＶγ峰面积，根据两者之比和已求得的＾１５２     

Filter back—projection technique applied to Abel inversion

The inverse Abel transform is applicable to optically thin plasma with cylindrical symmetry,which is often encountered in plasma physics and inertial(or magnetic)confinemant fusion.The filter back-projection technique is modified,and then a new method of inverse Abel transform is presented.     

The Application of Barr Numerical Method to Realize Abel Inversion

An 8-channel HCN laser interferometer will be installed on HL-2A in near term. In order to get the spatial profile of the electron density Barr numerical method is adopted to realize the Abel inversion. In this article the result of the Abel inversion by Matlab GUI is given which can be updated to process the measured data of the 8-channel laser interferometer and provide the spatial distribution of the electron density.     

An Analytical Method for the Abel Inversion of Asymmetrical Gaussian Profiles

An analytical algorithm for fast calculation of the Abel inversion for density profile measurement in tokamak is developed. Based upon the assumptions that the particle source is negligibly small in the plasma core region, density profiles can be approximated by an asymmetrical Gaussian distribution controlled only by one parameter VoID and VoID is constant along the radial direction, the analytical algorithm is presented and examined against a testing profile. The validity is confirmed by benchmark with the standard Abel inversion method and the theoretical profile. The scope of application as well as the error analysis is also discussed in detail.     

Analysis of Reverse Flow in Inverted U-Tubes of Steam Generator under Natural Circulation Condition

In this paper, we report on the analysis of reverse flow in inverted U-tubes of a steam generator under natural circulation condition. The mechanism of reverse flow in inverted U-tubes of the steam generator with natural circulation is graphically analyzed by using the full-range characteristic curve of parallel U-tubes. The mathematical model and numerical calculation method for analyzing the reverse flow in inverted U-tubes of the steam generator with natural circulation have been developed. The reverse flow in an inverted U-tube steam generator of a simulated pressurized water reactor with natural circulation is analyzed. Through the calculation, the mass flow rates of normal and reverse flows in individual U-tubes are obtained. The predicted sharp drop of the fluid temperature in the inlet plenum of the steam generator due to reverse flow agrees very well with the experimental data. This indicates that the developed mathematical model and solution method can be used to correctly predict the reverse flow in the inverted U-tubes of the steam generator with natural circulation. The obtained results also show that in the analysis of natural circulation flow in the primary circuit, the reverse flow in the inverted U-tubes of the steam generator must be taken into account.     

Fast Data Processing of a Polarimeter-Interferometer System on J-TEXT

A method of fast data processing has been developed to rapidly obtain evolution of the electron density profile for a multichannel polarimeter-interferometer system(POLARIS)on J-TEXT. Compared with the Abel inversion method, evolution of the density profile analyzed by this method can quickly offer important information. This method has the advantage of fast calculation speed with the order of ten milliseconds per normal shot and it is capable of processing up to 1 MHz sampled data, which is helpful for studying density sawtooth instability and the disruption between shots. In the duration of a flat-top plasma current of usual ohmic discharges on J-TEXT, shape factor u is ranged from 4 to 5. When the disruption of discharge happens, the density profile becomes peaked and the shape factor u typically decreases to 1.     

竖直圆管中泡状流含汽率径向分布的统计测量方法

为了研究竖直圆管中高含汽率泡状流的含汽率径向分布,设计了一种测量含汽率径向分布的方法.该方法通过统计投影视图中的像素信息得到泡状流的投影含汽率,根据汽泡投影重叠概率计算出截面含汽率在投影面上的边缘分布;再基于竖直圆管中含汽率分布轴对称的假设,使用改进的傅里叶级数展开方法求解Abel逆变换,计算出含汽率沿圆管径向的分布.为验证该方法的有效性,测量了较低含汽率时的泡状流径向含汽率,并与匹配方法的测量结果进行比较.实验结果表明:此方法能得到高含汽率或含汽率近壁分布等其他方法难以测量的含汽率分布.     

Online plasma diagnostics of a laser-produced plasma

In this study,we report a laser interferometry experiment for the online-diagnosing of a laserproduced plasma.The laser pulses generating the plasma are ultra-fast(30 femtoseconds),ultraintense(tens of Terawatt) and are focused on a helium gas jet to generate relativistic electron beams via the laser wakefield acceleration(LWFA) mechanism.A probe laser beam(λ?=?800 nm) which is split-off the main beam is used to cross the plasma at the time of arrival of the main pulse,allowing online plasma density diagnostics.The interferometer setup is based on the No Marski method in which we used a Fresnel bi-prism where the probe beam interferes with itself after crossing the plasma medium.A high-dynamic range CCD camera is used to record the interference patterns.Based upon the Abel inversion technique,we obtained a 3D density distribution of the plasma density.     

Response functions of the convection-dispersion equations describing radionuclide migration in a semi-infinite medium

Analytic expressions are derived for the response functions for the set of n coupled convection-dispersion equations in 1-D and with constant coefficients, for an n-member radioactive decay chain. The one-sided Laplace transform is applied to this set of partial differential equations, and eigen vectors and eigen values of the resulting system of equations are used to obtain general expressions for the Laplace transforms of the response functions. These are then inverted to produce analytic expressions for the response functions. These are used to solve problems with arbitrary time-varying boundary condition using convolutions. Laplace transforms of systems having similar characteristics can be written readily using results presented in this paper.     

Tomography of a simply magnetized toroidal plasma

Optical emission spectroscopy is a passive diagnostic technique,which does not perturb the plasma state.In particular,in a hydrogen plasma,Balmer-alpha(Hα) emission can be easily measured in the visible range along a line of sight from outside the plasma vessel.Other emission lines in the visible spectral range from hydrogen atoms and molecules can be exploited too,in order to gather complementary pieces of information on the plasma state.Tomography allows us to capture bi-dimensional structures.We propose to adopt an emission spectroscopy tomography for studying the transverse profiles of magnetized plasmas when Abel inversion is not exploitable.An experimental campaign was carried out at the Thorello device,a simple magnetized torus.The characteristics of the profile extraction method,which we implemented for this purpose are discussed,together with a few results concerning the plasma profiles in a simply magnetized torus configuration.     

Diagnosis of Electron, Vibrational and Rotational Temperatures in an Ar/N2 Shock Plasma Jet Produced by a Low Pressure DC Cascade Arc Discharge

In this paper,a low pressure Ar/N2 shock plasma jet with clearly multicycle alternating zones produced by a DC cascade arc discharge has been investigated by an emission spectral method combined with Abel inversion analysis.Plasma emission intensity,electron,vibrational and rotational temperatures of the shock plasma have been measured in the expansion and compression zones.The results indicate that the ranges of the measured electron temperature,vibrational temperature and rotational temperature are 1.1 eV to 1.6 eV,0.2 eV to 0.7 eV and 0.19 eV to 0.22 eV,respectively,and it is found for the first time that the vibrational and rotational temperatures increase while the electron temperature decreases in the compression zones.The electron temperature departs from the vibrational and the rotational temperatures due to non-equilibrium plasma efects.Electrons and heavy particles could not completely exchange energy via collisions in the shock plasma jet under the low pressure of 620 Pa or so.