搜索结果: 1-12 共查到“知识库 物理学 AMS”相关记录12条 . 查询时间(0.213 秒)
182Hf的AMS测量技术研究
182Hf 岩石样品 加速器质谱 核环境工程
2013/4/17
为实现对182Hf岩石样品的AMS精确测量，基于HI-13串列加速器对测量技术和方法等进行了系统的改进，主要包括：182Hf空白样品的制备、偏置束流的同时监测技术、加速器系统稳定性检验、交替测量方案的实施、182W扣除方法的改进、模拟样品测量检验、岩石样品测量检验及测量结果可信度检验等。实验结果表明，对于1×10-10(182Hf/180Hf)水平的模拟样品，测量结果的相对不确定度约为12%，基本...
AMS measurement of In-situ produced cosmogenic 10Be in Loess Quartz in Luochuan
Loess in Luochuan In-situ produced cosmogenic 10Be AMS measurement
2009/8/17
Loess is the most important and the most typical continental classic sediments of Quaternary. So the measurement of In-situ produced cosmogenic 10Be is expected to be used for the Loess stratigraphic ...
A Bragg curve detector and its application in AMS measurements for medium-weight nuclides
Bragg curve detector isobaric identification AMS 36Cl 41Ca
2009/8/17
The schematic layout and principle of a Bragg curve detector were showed in this paper. A Bragg curve detector was systemically modified and its performance was improved. The total energy resolution o...
Measurements of 79Se with AMS based on extracting molecular negative ions
79Se accelerator mass spectrometry (AMS) extraction form molecular negative ions isobar Bragg curve detector
2009/8/14
A new method for measuring selenium-79 with AMS, which is based on extracting molecular negative ions, is described in this paper. According to the experimental results, the extraction ion form SeO2－ ...
Developments in accelerator mass spectrometry (AMS) method for 182Hf
182Hf accelerator mass spectrometry (AMS) HfF4 injector solid-phase reaction
2009/8/14
The present detection limit for 182Hf at CIAE HI-13 AMS systems could not satisfy various applications (e. g. detection of a nearby supernovae signal). Therefore, techniques were developed in this wor...
236U及其加速器质谱（AMS）测量
236U 加速器质谱 环境监测
2010/2/24
236U是一种长寿命放射性核素， 其半衰期为T1/2=2.342(3)×107 a， 在自然界的含量极微， 天然铀中 236U/238U的原子比约为～10-14。 目前， 对于236U及其测量的研究报道较少。首先介绍了236U的产生， 并对地球中 236U的总量进行了估算。 概述了236U测定在亿年级中子注量率积分评估、 核环境和核活动监测， 以及地质学等领域中的重要应用。 最后，对国内外加速器质...
NEC14C测量AMS系统离子源升级
加速器质谱 离子源 球面电离器 引出流强
2009/3/2
为提高样品测量效率，对MC-SNICS多靶位铯溅射负离子源进行了升级改进。改进后的离子源采用球面电离器代替原有的锥面电离器，对供铯系统也进行了比较彻底的改造，通过参数优化，12C-引出流强最大可达近150μA，比原有离子源提高了1倍以上。流强的提高增加了加速器的束载效应，导致纹波变大，对测量稳定性造成一定影响。通过增加主分析磁铁后的光阑孔径和优化束流传输，可使AMS保持高的测量精度，同时对测量本底...
Use of 14C - AMS in the Study of Biological Production in Coastal Upwelling Areas
14C - AMS Biological Production Coastal Upwelling Areas
2010/10/22
We describe the use of the 14C-AMS technique to study the influence of upwelling waters to the local biological production, at Arraial do Cabo, Brazil. Results on ¢14C from seaweed tissues incuba...
AMS Dating of Early Shellmounds of the Southeastern Brazilian Coast
AMS Dating Early Shellmounds the Southeastern Brazilian Coast
2010/10/28
This paper discusses the chronology of prehistoric settlements of the central-south Brazilian coast. A charcoal sample from a coastal shellmound of Rio de Janeiro State was dated by 14C-AMS to 7; 860§...
AMS测量中同量异位素的鉴别方法
加速器质谱 同量异位素 粒子鉴别
2010/2/23
在加速器质谱测量中,存在同位素和同量异位素的干扰.排除同位素的干扰是开展超微量核素分析的重要课题之一.主要介绍了加速器质谱测量中同量异位素的几种鉴别、排除方法,以及这些方法的原理、发展及应用.There are interference of isotopes and isobars in accelerator mass spectrometry (AMS) measurements. Elim...
AMS在核物理与天体物理研究中的应用
加速器质谱学 泡利不相容原理 超新星
2010/2/24
加速器质谱学方法在核物理与天体物理研究中有重要应用.主要介绍了该方法在寻找泡利不相容原理的违背事例和超新星活动研究等工作中的应用. As an ultra high sensitive analyzing method, accelerator mass spectrometry is playing an important role in the studies of nuclear phys...