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81.
At ISOLDE (CERN),an on-line test bench is dedicated to charge breeding experiments with a 14GHz Phoenix ion source,for the investigation of the 1 →n scenario at next generation ISOL-type facilities.This year,various technical developments have been undertaken for intensifying the tests of the on- line performances of the booster with a high diversity of stable and radioactive ion beams.This contribution will present an overview of the latest developments,the current challenges,and some perspectives for the future use of the Phoenix booster for physics experiments at ISOLDE.  相似文献   
82.
The low-pressure rf plasma of a secondary neutral mass spectrometer (e-gas SNMS) was connected with a time-of-flight (ToF) mass spectrometer for the first time. As opposed to ToF–SIMS in e-gas SNMS, the primary ion pulse cannot be used for triggering the flight time measurement. Therefore, an extraction pulse is used which at a defined time loads an ion package from the beam of the post-ionised particles into the ToF spectrometer. The newly developed ToF–SNMS system is described, and first experimental results are presented.  相似文献   
83.
实验表明,在TE011模式园柱形腔中,不但可以使用扁平样品管测量水溶液样品的ESR波谱,而且获得好的腔品质因子Q和高品质的ESR信号。所观察到的信号高度,是使用最佳尺寸毛细管样品时最大信号高度的3.2倍;又是在具有波导尺寸的TE102腔中使用扁平样品管时所获得信号高度的3倍。本文对此作了定性的理论分析。  相似文献   
84.
BEPC-LINAC试验束上1GeV/c多粒子磁谱仪的设计和性能测量   总被引:2,自引:0,他引:2  
试验束上2Q2D结构的磁谱仪系统由2块二极磁铁和2块四极磁铁以及位置灵敏探测器组成.该磁谱仪的接收立体角5×10–4sr,动量范围0.2—1.3GeV/c.测量了聚焦面上的束流截面和动量谱.介绍了一种测量电子与质子飞行时间差的动量测量方法.  相似文献   
85.
Penning trap mass spectrometry has reached a state that allows its application to very short-lived nuclides available from various sources of radioactive beams. Mass values with outstanding accuracy are achieved even far from stability. This paper illustrates the state of the art by summarizing the status of the ISOLTRAP experiment at ISOLDE/CERN. Furthermore, results of mass measurements on unstable rare earth isotopes will be given. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
86.
阿达玛变换成像光谱术的研究   总被引:3,自引:0,他引:3  
本文论述了阿达玛变换成像光谱仪的基本原理,探讨了工作模式和若干设计问题,利用自行研制的实验装置,在可见波段获得了各种透明字形的成像光谱图。采用对称π变换和快速δ阿达玛变换,改善了实验数据的处理方法。  相似文献   
87.
A new form of charged particle energy analyser is proposed. It is broadly based on the 180° magnetic spectrograph, but is intended to detect charged particles moving out of the dispersion plane with a helical motion. The analyser has the capability to acquire charged particle energy spectra over a large energy range, similar to those acquired in Auger electron spectroscopy, ca. 2500 eV and large angular range, up to 90°, in parallel. These conditions are more favourable for surface analysis by electron spectroscopy at high vacuum, where for example an electron energy resolution of 0.2% to 0.5% is typical. Expressions showing how the landing positions of the charged particles on the detector vary as a function of energy and polar take off angle are determined as well as the conditions for optimum energy resolution at a range of polar take off angles. The equations reveal that in general, the device obtains the highest resolution at angles of revolution greater than 180°. The design is simple and could be easily put into practice using available material and technologies and be used to analyse the energies of electrons emitted from a sample placed in a scanning electron microscope. It can be made to function with a primary electron beam of any desired energy and could fit in to the small space between the sample and the end of an electron column. However, the device is difficult to retrofit into existing SEMs and ideally an SEM column needs to be designed to work in association with the analyser. The direction of the magnetic field of the analyser is coincident with the axis of the electron gun so that the primary beam is little influenced by the magnetic field and symmetry can be maintained in the primary beam electron column. Because the device is intended to acquire electron spectra in parallel, any movement of the primary beam on the sample because of a ramping field in the analyser is avoided. The field of view and the effect of the analyser upon the operation of the SEM are discussed. Spectra including elastic and Auger peaks reveal an energy resolution of ~4 eV at 900‐eV electron energy. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
88.
对RoHS检测用X荧光光谱仪提出了计量性能要求及校准方法,并验证了方法的可行性,为今后规程的制定提供参考。  相似文献   
89.
气相色谱-质谱联用法测定化妆品中邻苯二甲酸酯类化合物不确定度的主要来源有标准溶液引入的不确定度、样品引入的不确定度、样品处理过程中引入的不确定度。以邻苯二甲酸二丁酯(DBP)为例,对各不确定度分量进行了评定,计算了合成不确定度和扩展不确定度。当化妆品中DBP测量结果为10.39 mg/L时,其扩展不确定度为0.50 mg/L(k=2)。  相似文献   
90.
A simple, sensitive, and specific method with gas chromatography-mass spectrometry was developed for simultaneous extraction and derivatization of amphetamines (APs) and 3,4-methylenedioxyamphetamines (MDAs) in human urine by using a monolithic silica spin column. All the procedures, such as sample loading, washing, and elution were performed by centrifugation. APs and MDAs in urine were adsorbed on the monolithic silica and derivatized with propyl chloroformate in the column. Methamphetamine-d5 was used as an internal standard. The linear ranges were 0.01-5.0 μg mL−1 for methamphetamine (MA) and 3,4-methylenedioxymethamphetamine (MDMA) and 0.02-5.0 μg mL−1 for amphetamine (AP) and 3,4-methylenedioxyamphetamine (MDA) (coefficient of correlation ≧0.995). The recovery of APs and MDAs in urine was 84-94%, and the relative standard deviation of the intra- and interday reproducibility for urine samples containing 0.1, 1.0, and 4.0 μg mL−1 of APs and MDAs ranged from 1.4% to 13.6%. The lowest detection limit (signal-to-noise ratio ≧ 3) in urine was 5 ng mL−1 for MA and MDMA and 10 ng mL−1 for AP and MDA. The proposed method can be used to perform simultaneous extraction and derivatization on spin columns that have been loaded with a small quantity of solvent by using centrifugation.  相似文献   
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