有益的、负责任的、可持续的

国际原子能机构为帮助着手发展核电的国家明智地、有益地、安全地和可靠地发展核电做好充分准备     

测量气体放射性的电离室的灵敏度的估计

空气中所含气态放射性物质的测量,在一般剂量测量中常用充以待测气体的电离室来进行。如复估计此种装置对不同能量的β放射性气体的灵敏度或刻度常数,可以利用下面的简单公式及曲线图。     

常规的与浸泡的金属离子植入的比较

可以把真空弧产生的金属等离子体用作常规金属离子植入用的离子源中离子的原材料，或可用作等离子体浸泡离子植入的浸泡等离子体。在两种情况下，产生等离子体的基本方法是一样的；方法是简单折、有效的，并可与各种金属一起使用。不同种类的真空弧离子源由本文作者及其他人研制出来，它们作为金属离子植入工具的适用性已为人们公认。金属等离子体浸泡表面处理是一种刚出现的方法，它的性能和应用是本研究的课题。不论在所使用的工序     

金的热中子吸收截面的测量

本文介绍利用中子晶体谱仪和4π-MnSO_4溶液探测器测量金的热中子吸收截面的方法和结果;讨论了某些对测量结果有影响的因素,并引进了相应的修正。金的热中子(E=0.0253电子伏)吸收截面的测量结果为σ_a=98.8±1.7靶,这个结果与国外近年来发表的测量结果符合得较好。     

铀的生产法的改进

美国在国外的生产铀的公司,当与美国原子能委员会签定的合同满期之后,正在面临着失去他们市场的威胁。有鉴于此,这些公司正在企图以改进工艺的办法来降低生产的成本,从而达到保持他们     

铀的宏观浸蚀的研究

本文研究出一种醋酸-铬酸-水溶液电解浸蚀显露金属铀宏观组织的方法,效果良好,并与过去常用的几种方法进行了比较。     

科罗拉多高原的铀的指示植物

在科罗拉多高原采用了两种植物找铀的方法。第一种方法建立在对深根植物的化学分析基础上,这种植物的根能延展至矿体并从其中吸附铀;该法所探测的是通过植物根部所吸附的但可分析的元素量。第二种方法包括绘制指     

Development of laser ion source for heavy ion applications

We have been developing a high-performance laser ion source (LIS) for practical applications since 2009. Ideally, the LIS should generate a carbon beam with a peak current of 20 mA and a pulse duration of over 1 μs. We selected a Nd:YAG laser with a Gaussian-coupled resonator as the laser source based on our experience of generating high-charge-state ion beams. This laser can produce fundamental pulses with a power of 650 mJ and durations of about 6 ns. The graphite target used is 10 cm high and 10 cm in diameter, as it can be irradiated with up to 10⁵ laser shots. The maximum extraction voltage was designed to be 50 kV. We have already finished designing the LIS and we commenced fabrication. We intend to measure the source performance by performing plasma and beam tests up to the end of March 2011.     

尼尔逊离子源重离子束流的发射度

尼尔逊离子源已广泛地应用于重离子加速器、同位素分离器及研究用离子注入机。用于C-600离子注入机的尼尔逊离子源,目前已获得达100μA的三十余种重离子束,其中有近二十种固体元素。     

微波离子源聚焦离子束光学系统的研究

设计了一种微波离子源的聚焦离子束光学系统,分析计算了光学系统的束径。并数值模拟了由空间电荷作用造成的束径增宽效应,找出了影响束斑大小的主要因素和减小束径的方法。测试结果表明,在束能在２５ｋｅＶ时,束流为１４８ｎＡ,束径约为２０μｍ左右。     

离子注入与离子束混合两用机

早在1979年,为了解决应用于高温高真空环境下的轴承的自润滑问题,我们就着手采用     

离子注入、分析联用靶室

近年来,离子注入和离子束分析技术,应用相当广泛,已扩展到许多新的领域,形成了一种多学科性的边缘学科。 离子注入已作为一种成熟的技术广泛地应用在半导体工业上,在半导体制造工艺方面,它比传统的热扩散法显示出多方面的优越性。同时在材料改性方面也引起人们的极大兴趣,许多金属部件在实际使用时起作用的是金属表面的性质,而离子注入正好是能够改变金属表面性质(如硬度、磨损、腐蚀等)的有效途径。此外,离子注入技术用来改变光学表面指定区域的反射率、折射率,这在“集成光学”中是一项有效技术,也有人利用离子注入技术研制记忆元件(如磁泡)以及提高超导材料的超导性能等。     

Use of a duoplasmatron ion source for negative ion generation

The use of electronegative species as primary ions considerably enhances the emission of positive secondary ions in SIMS. Considering furthermore that negative primary ions can be required due to instrumental configurations (e.g. the Cameca NanoSIMS 50 requires an opposite polarity of the primary and secondary ions), O⁻ ion bombardment is employed in SIMS analysis. These O⁻ ions are typically created in a duoplasmatron source, which suffers however from its low brightness and which is thus not suited for high resolution imaging applications. The development of new (electro)negative ion sources is thus necessary to optimize the analysis of electropositive elements in terms of lateral resolution and sensitivity.In this paper, we present the performance of a duoplasmatron ion source generating F⁻, Cl⁻, Br⁻ and I⁻ ion beams. In particular, we experimentally determine on a dedicated test bench the brightness of the source in the F⁻, Cl⁻, Br⁻ and I⁻ modes as a function of the gas pressure, the magnetic field strength and the arc current in the source. The obtained results are compared to the performances of the duoplasmatron in the standard O⁻ mode. In this context, a five times higher brightness was found for F⁻ (200 A/cm² sr) compared to the standard O⁻ (42 A/cm² sr).     

High precision Hf ion implantation using a high-current ion implanter

The development of accurate mass spectrometry, enabling the identification of all the ions extracted from the ion source and further precise ¹⁸⁰Hf isotope implantation, in a high current implanter is described. The spectrometry system uses two signals (x-y graphic), one proportional to the magnetic field (x-axes), taken from the high-voltage potential with an optic fiber system, and the other proportional to the beam current intensity (y-axes), taken from a beam-stop. The ion beam mass register in a mass spectrum of all the elements magnetically analyzed with the same radius and defined by a pair of analyzing slits as a function of their beam intensity is presented. Hence, it is possible to implant ¹⁸⁰Hf⁺, with less than 1% contamination from neighboring isotopes, in order to conduct material characterization studies by Perturbed Angular Correlations. The precision of the low fluence ion implantation has been done by neutron activation analysis.     

Polarized ion source

A polarized ion source giving a current of about 0.1A has been constructed. The background from nonpolarized deuterons is 1–2%, and that from protons is 10–15%. The degree of alignment of the deuterons has been checked; this is revealed in the anisotropy of the angular distribution of partides in the reaction T(d,n)He⁴.The degree of alignment equals P₂ = –0.32₆ ± 0.01, which agrees closely with the theoretical value P₂ = –0.328 for an orienting field of 10 Oe. This latter leads to the conclusion that the polarization of the protons is about 50% and that of the deuterons about 33%. Cooling the water dissociator with liquid nitrogen increases the intensity approximately by a factor of two.Translated from Atomnaya Énergiya, Vol. 17, No. 1, pp. 17–22, July, 1964     

Investigation of the ion acoustic effect during focused ion beam irradiation

Acoustic waves induced by an intensity modulated focused ion beam (FIB) have been measured. The experiments were performed with Ga⁺ ions of 35 keV at a current of 3 nA and variable chopping frequency up to 10 MHz. The acoustic signals were detected by means of a piezoelectric sensor with integrated pre-amplifier. A dependence on the sample material was found during line scan FIB motion. The results show that the ion-acoustic effect may be utilized for an alternative sample imaging and material analysis in FIB systems.     

微波离子枪离子束光学的数值模拟

用数值模拟方法研究了聚焦离子束系统中微波离子枪的束光学性能，将离子枪看作由源等离子体极和Ｏｒｌｏｆｆ－Ｓｗａｎｓｏｎ透镜组成的双级加速系统，分析了各参对束发射特性的影响。结果展示出引出束光学主要取决于引出导流系数和电势分布，在一定条件下可获得发散度小的离子束。