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991.
Measurement of the analyzing power in the Primakoff process with a high-energy polarized proton beam
Carey DC Coleman RN Corcoran MD Cossairt JD Derevschikov AA Grosnick DP Hill D Imai K Konaka A Kuroda K Lehar F de Lesquen A Lopiano D Luehring FC Maki T Makino S Masaike A Matulenko YA Meschanin AP Michalowicz A Miller DH Miyake K Nagamine T Nakano T Nessi-Tedaldi F Nessi M Nguyen C Nurushev SB Ohashi Y Pauletta G Penzo A Phillips GC Read AL Roberts JB van Rossum L Salvato G Schiavon P Shima T Solovyanov VL Spinka H Stanek RW Takashima R Takeutchi F Tamura N Tanaka N Underwood DG Vasiliev AN 《Physical review letters》1990,64(4):357-360
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Summary Methods for the determination of Th in the range of low concentrations are compiled and discussed. Application of spectrophotometry and voltammetry is investigated. Spectrophotometry is applicable down to concentrations of the order of 0.1 g/l as long as the ratio U:Th is low. Voltammetric determination of Th is not possible in the presence of Al. 相似文献
995.
H. Hora H. Haseroth T. Henkelmann C. E. Hill G. Korschinek R. Matulioniene C. S. Taylor 《Czechoslovak Journal of Physics》1992,42(9):927-938
The need for highly charged heavy ions from projected particle accelerators has recently led to a re-evaluation of the complex processes of ion production in laser generated plasmas. Possible mechanisms for the production of intense beams of high charge state ions are investigated as is the experimental evidence for these mechanisms. The hypothesis that 20 keV ions are driven by hot electrons is not supported by experimental work to date. This work, on the other hand, suggests that 30ps pulsation is the basic mechanism for the acceleration of tantalum ions up to charge state 8+ whose energy increases linearly with charge state up to 24keV. For long pulses and charge states between 8+ and 18+, it appears that there is a secondary mechanism of electron impact ionisation by plasma electrons of approximately 200 eV in the plasma in front of the target, resulting in ions whose energy of around 24 keV is independent of charge state. 相似文献
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Thron JL Allison WW Alner GJ Ambats I Ayres DS Balka LJ Barr GD Barrett WL Benjamin D Border PM Brooks CB Cobb JH Cockerill DJ Courant H Dawson JW Demuth DM Edwards VW Ewen B Fields TH Garcia-Garcia C Giles RH Giller GL Goodman MC Gray RN Heilig SJ Hill N Hoftiezer JH Jankowski DJ Johns K Kafka T Kasahara SM Kochocki J Leeson W Litchfield PJ Longley NP Lopez FV Lowe MJ Mann WA Marshak ML May EN Maxam D McMaster L Milburn RH Miller WH Minor CP Napier A Oliver WP Pearce GF Perkins DH Peterson EA 《Physical review D: Particles and fields》1992,46(11):4846-4851
1000.
J.S. Cowpe J.S. Astin R.D. Pilkington A.E. Hill 《Spectrochimica Acta Part B: Atomic Spectroscopy》2007,62(12):1335-1342
Response Surface Methodology (RSM) was employed to optimize LIBS analysis of single crystal silicon at atmospheric pressure and under vacuum conditions (pressure 10− 6 mbar). Multivariate analysis software (StatGraphics 5.1) was used to design and analyze several multi-level, full factorial RSM experiments. A Quality Factor (QF) was conceived as the response parameter for the experiments, representing the quality of the LIBS spectrum captured for a given hardware configuration. The QF enabled the hardware configuration to be adjusted so that a best compromise between resolution, signal intensity and signal noise could be achieved. The effect on the QF of simultaneously adjusting spectrometer gain, gate delay, gate width, lens position and spectrometer slit width was investigated, and the conditions yielding the best QF determined. 相似文献