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101.
For the purpose of producing high intensity, multiply charged metal ion beams, the dual hollow cathode ion source for metal ions (DUHOCAMIS) was derived from the hot cathode Penning ion source combined with the hollow cathode sputtering experiments in 2007. To investigate the behavior of this discharge geometry in a stronger magnetic bottle-shaped field, a new test bench for DUHOCAMIS with a high magnetic bottle-shaped field up to 0.6 T has been set up at the Peking University. The experiments with magnetic fields from 0.13 T to 0.52 T have indicated that the discharge behavior is very sensitive to the magnetic flux densities. The slope of discharge curves in a very wide range can be controlled by changing the magnetic field as well as regulated by adjusting the cathode heating power; the production of metallic ions would be much greater than gas ions with the increased magnetic flux density; and the magnetic field has a much higher influence on the DHCD mode than on the PIG mode. 相似文献
102.
M. C. Fujiwara G. Andresen W. Bertsche A. Boston P. D. Bowe C. L. Cesar S. Chapman M. Charlton M. Chartier A. Deutsch J. Fajans R. Funakoshi D. R. Gill K. Gomberoff J. S. Hangst W. N. Hardy R. S. Hayano R. Hydomako M. J. Jenkins L. V. Jørgensen L. Kurchaninov N. Madsen P. Nolan K. Olchanski A. Olin R. D. Page A. Povilus F. Robicheaux E. Sarid D. M. Silveira J. W. Storey R. I. Thompson D. P. van der Werf J. S. Wurtele Y. Yamazaki 《Hyperfine Interactions》2006,172(1-3):81-89
ALPHA is an international project that has recently begun experimentation at CERN’s Antiproton Decelerator (AD) facility.
The primary goal of ALPHA is stable trapping of cold antihydrogen atoms with the ultimate goal of precise spectroscopic comparisons
with hydrogen. We discuss the status of the ALPHA project and the prospects for antihydrogen trapping. 相似文献
103.
基于捕获的新型正电子束及应用 总被引:1,自引:1,他引:0
基于捕获的新型正电子束技术是通过潘宁阱中捕获、约束和积累正电子而发展的新一代正电子束技术。本文介绍正电子的捕获、冷却,压缩技术,基于捕获的正电子束形成技术,以及该技术将来发展展望,最后讨论该技术在原子物理学和材料科学等多个领域的应用。 相似文献
104.
NO是血管舒张代谢的产物.生物体内由NO自由基导致的不同生理作用之间存在复杂的平稳关系,近年来对NO的研究引起众多生物学家和化学家的极大兴趣[1],特别关注于NO检测的研究.定量测定NO的方法已有多种[2,3],但尚无直接从细胞或生物体系中检测NO的... 相似文献
105.
M. F. Andersen A. Kaplan T. Grünzweig N. Davidson 《Communications in Nonlinear Science & Numerical Simulation》2003,8(3-4):289
We discuss a recently demonstrated type of microwave spectroscopy of trapped ultra-cold atoms known as “echo spectroscopy” [Phys. Rev. Lett., 2003;90:023001[1]–[4]]. Echo spectroscopy can serve as an extremely sensitive experimental tool for investigating quantum dynamics of trapped atoms even when a large number of states are thermally populated. We show numerical results for the stability of eigenstates of an atom-optics billiard of the Bunimovich type, and discuss its behavior under different types of perturbations. Finally, we propose to use special geometrical constructions to make a dephasing free dipole trap. 相似文献
106.
107.
Vladimir V. Shevchenko Natalya G. Zhegalova Andey O. Borzenko Valerij A. Nikolaev 《Helvetica chimica acta》2008,91(3):501-509
The efficiency and validity of different chemical substrates for trapping bis(methoxycarbonyl)carbene (=2‐methoxy‐1‐(methoxycarbonyl)‐2‐oxoethylidene; 1 ) is dependent on the conditions of carbene generation. On conventional photolysis of dimethyldiazomalonate (=2‐diazopropanedioic acid dimethyl ester; 2 ) by long‐wave UV light (through a Pyrex filter, λ>290 nm), the most powerful trap for carbene 1 in the series of substrates Me2S, MeOH, cyclohexane, and pyridine is Me2S (with an efficiency ratio of ca. 6 : 4 : 2 : 1, resp.). When short‐wave decomposition of diazomalonate 2 is employed (through a quartz filter, λ>210 nm), more reliable and useful chemical traps for bis(methoxycarbonyl)carbene ( 1 ) are pyridine and cyclohexane, whose adducts with 1 are rather stable under short‐wave‐irradiation conditions. Application of alcohols for the trapping of 1 proves to be preferential when simultaneous monitoring of carbene and oxoketene formation during photolysis is necessary. 相似文献
108.
Characteristics of charge traps in TlInS2 single crystals are investigated by the use of thermally stimulated current (TSC) technique. The TSC spectra of the sample from 80 K to 300 K are recorded at a constant heating rate. The spectra reveal that there are several trapping levels associated with the complex structure of overlapping peaks. The experimental results indicate that the traps in TlInS2 associated with the spectra in the measuring range of temperature obey the monomolecular (first order) kinetics. Thus, the spectra are resolved into first order shaped peaks by the use of computerized best fit procedure. The trapping parameters; such as the energy depth, temperature dependent frequency factor and capture cross section, together with concentrations of the corresponding six discrete levels are computed. These centers all having low capture cross sections with strong temperature dependence are found to be at the energies of 0.11 eV, 0.22 eV, 0.25 eV, 0.26 eV, 0.29 eV and 0.30 eV with high concentrations of 6.6 × 1016, 2.0 × 1017, 3.3 × 1017, 9.6 × 1016, 2.3 × 1017 and 4.0 × 1017 cm?3, respectively. 相似文献
109.
An interactive mixed-order thermoluminescence (TL) glow curve deconvolution function is presented for the first time in which the retrapping of thermally stimulated charge carriers in deep traps during the heating stage is taken into account. Considering this transition in the set of differential equations by describing the TL process and by solving them, an analytical function for TL intensity was obtained. This equation reduces to the known deconvolution function for the mixed-order model in the limiting case of saturation of deep trapping (DT) states. In intermediate cases, where the DT states are partially occupied, the proposed function acts as a real interactive model which allows the thermally stimulated electrons to be retrapped to deep electron traps. Applicability of the proposed model in a real TL system is also presented and discussed. 相似文献
110.