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排序方式: 共有114条查询结果,搜索用时 15 毫秒
1.
一种用于冶金炉前快速分析的新仪器——激光诱导击穿光谱仪 总被引:3,自引:2,他引:1
冶金炼钢要求快速分析冶金炉前样品来及时掌握冶炼过程。文章介绍了自主研制的一种新型的光谱仪——激光诱导击穿光谱仪,该仪器采用ns级脉宽的Nd∶YAG激光器作为样品离子化光源,激光聚焦样品表面激发产生的等离子体光谱依次经帕邢-龙格光学系统进行分光、光电倍增管探测、门控积分器积分、模拟数字转换器转换后获得的最终结果输入计算机进行数据处理。和目前冶金炉前样品分析常用的光谱仪相比,该仪器无需样品预处理,分析速度快(1 min或更少),准确灵敏度高,非常适用于冶金炉前样品的快速分析。近年来随着光纤技术的迅速发展,使用该仪器进行钢液实时在线分析和动态控制冶金工艺必将成为现实。 相似文献
2.
Anjam Khursheed 《Optik》2009,120(6):280-288
This paper presents the design of a multi-beam charged particle instrument that simultaneously focuses electrons, gallium, oxygen and cesium ions onto the same sample. In addition, the instrument has provision to capture the spectra of both secondary electrons and ions in parallel. The mass spectrometer part of the instrument is expected to detect and identify secondary ion species across the entire range of the periodic table, and also record a portion of their emitted energy spectrum. The electron energy spectrometer part of the instrument is designed to acquire the entire range of scattered electrons, from the low-energy secondary electrons through to the elastic backscattered electrons. 相似文献
3.
M. Mukherjee D. Beck K. Blaum G. Bollen J. Dilling S. George F. Herfurth A. Herlert A. Kellerbauer H. -J. Kluge S. Schwarz L. Schweikhard C. Yazidjian 《The European Physical Journal A - Hadrons and Nuclei》2008,35(1):1-29
ISOLTRAP is a Penning trap mass spectrometer for high-precision mass measurements on short-lived nuclides installed at the
on-line isotope separator ISOLDE at CERN. The masses of close to 300 radionuclides have been determined up to now. The applicability
of Penning trap mass spectrometry to mass measurements of exotic nuclei has been extended considerably at ISOLTRAP by improving
and developing this double Penning trap mass spectrometer over the past two decades. The accurate determination of nuclear
binding energies far from stability includes nuclei that are produced at rates less than 100 ions/s and with half-lives well
below 100ms. The mass-resolving power reaches 107 corresponding to 10keV for medium heavy nuclei and the uncertainty of the resulting mass values has been pushed down to below
10-8. The article describes technical developments achieved since 1996 and the present performance of ISOLTRAP. 相似文献
4.
5.
6.
W. Yu 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):509-511
The HERMES Collaboration installed a new Recoil Detector to upgrade the existing spectrometer to study hard exclusive processes
which provide access to generalised parton distributions (GPDs) and hence to the orbital angular momentum of quarks. The HERMES
Recoil Detector mainly consists of three components: a silicon detector surrounding the target cell inside the beam vacuum,
a scintillating fibre tracker and a photon detector with three layers of tungsten and scintillator bars in three different
orientations. All three detectors are located inside a solenoidal magnet which provides a 1T longitudinal magnetic field.
The Recoil Detector was installed in January 2006 and data taking will last until July of 2007. 相似文献
7.
P. Mason N. Marginean G. Montagnoli S. Beghini F. Scarlassara E. Farnea C. A. Ur A. Meroni A. M. Stefanini L. Corradi E. Fioretto I. V. Pokrovskiy B. Guiot A. Gadea J. J. Valiente-Dobón F. Della Vedova R. Orlandi E. Sahin D. R. Napoli L. Berti N. Toniolo S. Szilner M. Trotta M. Romoli M. La Commara D. Pierroutsakou M. Sandoli G. Pollarolo G. Benzoni 《The European physical journal. Special topics》2007,150(1):359-361
PRISMA is a magnetic
spectrometer installed at Laboratori Nazionali di Legnaro (Italy)
and designed for A=100–200, E=5–10 MeV-per-nucleon beams, and for
possible use with the proposed radioactive beam facility SPES. The
foremost features of the instrument are presented, along with the
outline of two data analyses exemplifying the effectiveness of
PRISMA-CLARA in studies of reaction
dynamics. 相似文献
8.
W. R. Plaß T. Dickel M. Petrick D. Boutin Z. Di T. Fleckenstein H. Geissel C. Jesch C. Scheidenberger Z. Wang 《The European physical journal. Special topics》2007,150(1):367-368
A novel system consisting of RF quadrupole and time-of-flight sections
is proposed, in which ions can be cooled, bunched, mass separated with a resolution sufficient to
differentiate between isobars, and guided to different experimental setups, e.g. for precision mass
measurements or mass-resolved decay spectroscopy. It enables multiplexed operation of
several connected experiments and interleaved measurements using different nuclides in one connected experiment.
Such a system could be employed advantageously at in-flight facilities, at which experiments with stopped
exotic nuclei are made possible using gas-filled stopping cells, such as SHIPTRAP at GSI, or potentially
at ISOL facilities. First results for individual stages of the system are presented. 相似文献
9.
Mittels Aktivierungsanalyse wurde der Gehalt an Arsen, Antimon, Kupfer, Phosphor und Zink in Halbleitersilizium bestimmt. Die Methode besteht aus zwei Schritten: 1. Gruppentrennung durch Anionenaustausch mit einem Gemisch von Salz- und Fluorwasserstoffsäure, 2. Selektive substöchiometrische Extraktion von Arsen und Kupfer mit Diäthyldithiocarbamat, von Antimon mit Cupferron und von Zink mit Dithizon. Phosphor wurde extraktiv als Phosphomolybdat abgetrennt. 相似文献
10.
本文在分析微机化四极质谱仪现状的基础上,以国产ZLS-150型四极质谱仪为原型,进行了四极质谱仪微机控制和数据处理系统的研制,提出了最小二乘质量标定方法。通过对质谱仪扫描规律的详细研究,探讨了新颖的定点扫描方式,较好地解决了监测过程中监测频率和监测组分数之间的矛盾。该系统经联机调试取得了满意效果。 相似文献