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31.
32.
双脉冲激光诱导等离子体在激光加工、元素检测、材料去除等领域有广阔的应用前景和发展空间,对其进行诊断具有重要意义。针对延迟双脉冲激光诱导铝等离子体的作用效果和影响机理,采用双波长干涉法对其时间演化规律展开研究。基于马赫-曾德尔干涉仪搭建了双波长干涉诊断系统,得到了双脉冲激光诱导等离子体干涉图。通过对干涉图的处理和分析,得到了等离子体电子密度随双脉冲激光延迟时间的变化规律。结果表明,随着双脉冲激光延迟时间的增加,第二束脉冲激光对等离子体电子密度的增强效果先加强后减弱。其中,双脉冲激光延迟时间为10 ns时,对等离子体电子密度的增强效果最强,在30 ns时刻,其中心区域平均电子密度可达6.49×1019 cm?3,相较于同等能量单脉冲激光诱导等离子体提升了26%。同时研究了延迟时间对第二束脉冲激光作用机制的影响。研究结果为双脉冲激光诱导等离子体的优化方向提供了参考。 相似文献
33.
Carleson measure characterization of Bloch functions 总被引:1,自引:0,他引:1
Lou Zengjian 《数学学报(英文版)》1996,12(2):175-184
We give several equivalences of Bloch functions and little Bloch functions. Using these results we obtain the generalized Carleson measure characterization of Bloch functions and the generalized vanishing Carleson measure characterization of little Bloch functions, that is,f B if and only if |D
f(z)|
p
(1-|z|2)p-1
dm(z) is a generalized Carleson measure;f B
0 if and only if |D
f(z)|
p
(1-|z|2)p-1
dm(z) is a generalized vanishing Carleson measure, whereD
f( > 0) is the fractional derivative of analytic functionf of order, m denotes the normalised Lebesgue measure.Supported partly by the Young Teacher Natural Science Foundation of Shandong Province. 相似文献
34.
T. Case K. M. Crowe K. Lou C. Petitjean W. H. Breunlich M. Jeitler P. Kammel B. Lauss J. Marton W. Prymas J. Zmeskal D. V. Balin V. N. Baturin Yu. S. Grigoriev A. I. Ilyin E. M. Maev G. E. Petrov G. G. Semenchuk Yu. V. Smirenin A. A. Vorobyov N. I. Voropaev P. Baumann H. Daniel F. J. Hartmann M. Mühlbauer W. Schott P. Wojciechowski 《Hyperfine Interactions》1993,82(1-4):295-302
Starting in 1989 an experiment was run at PSI to directly measure the final sticking probability in muon catalyzed dt fusion. This experiment was based on an active-target ionization chamber (IC) built at Gatchina, Russia, and an array of plastic neutron counters. In three runs approximately 5×106 isolated alpha signals were recorded with around one half of these occurring in the inner chamber region where we have more complete understanding of the systematic errors. Particularly from a long run in 1992 we were able to obtain a very clean sticking peak of some 5000 events. However, to reach an accurate value of sticking, all systematic effects and several major backgrounds had to be understood in detail. To this end a Monte Carlo code was written to simulate the full electrostatic environment of the IC and to recreate completely each signal type including the actual tritium decay noise from the live experiment. A slightly model dependent value of approx. 0.56±0.04% is obtained for final sticking. 相似文献
35.
W. Schott V. N. Baturin W. H. Breunlich T. Case H. Daniel F. J. Hartmann M. Jeitler P. Kammel K. Lou E. M. Maev J. Marton M. Mühlbauer C. Petitjean G. E. Petrov Yu. V. Petrov G. G. Semenchuk Yu. V. Smirenin A. A. Vorobyov P. Wojciechowski J. Zmeskal 《Hyperfine Interactions》1993,82(1-4):471-481
The triton energy of the muon capture reaction 3He t+v, where 3 He is the ground state of muonic3He, has been measured in order to investigate a possible heavy v admixture into the flavour with high sensitivity. 3 He has been formed via the pd fusion reaction by stopping – in an ionization chamber (IC) filled with an H/D gas mixture of 3% D concentration at a pressure of 161 bar. In a first short experiment 650 triton events were observed yielding an upper limit for the -heavy v mixing strength of 2.3×10–3 atE
0v=60 MeV. 相似文献
36.
P. Ackerbauer W. H. Breunlich M. Fuchs S. Fussy M. Jeitler P. Kammel B. Lauss J. Marton W. Prymas J. Werner J. Zmeskal K. Lou C. Petitjean P. Baumann H. Daniel F. J. Hartmann W. Schott T. von Egidy P. Wojciechowski D. Chatellard J. P. Egger E. Jeannet T. Case K. M. Crowe R. H. Sherman V. Markushin 《Hyperfine Interactions》1993,82(1-4):243-258
Complementary to the investigations of the most efficient dt cycle, also the other muon-induced fusion cycles in mixtures of hydrogen isotopes have been studied. The results of these dedicated experiments provide rich information about muon-induced few-body reactions and contribute significantly to a better overall understanding of CF. A summary of the recent progress will be presented. Special emphasis will be put on two characteristic examples, namely a new experimental approach to study the muonic cascade in H-D mixtures and the systematic study of hyperfine effects in muon-induced reactions. 相似文献
37.
For the first time the isomerization of 1,3,2-diazaphospholidine-2-sclenide dervatives in refluxing benzene in the presence of trace water was observed. The structures of isomerized products were determined by IR, ^1H NMR,^31P NMR, elemental analysis and X-ray crystallography. The mechanism of isomerization was also proposed. 相似文献
38.
The dispersed fluorescence spectra of Pb_2 dimer were recorded from the excitation of Ar~+ laser in HPOR. By the detailed spectroscopic analysis for this well-resolved fluorescence spectra, the ground state of pb_2 molecule and one of its electronically excited state were assigned preliminarily to be X~1∑_g~+ and F′Ⅱ_u state respectively.The spectral constants of the X and F are ω_e″=108.5 cm~(-1),ω_e″X_e″ = 0.209 cm~(-1), ω_e′=152.4 cm~(-1), ω_e′X_e′=0.636 cm~(-1) and T_e=19818,1 cm~(-1)., respectively 相似文献
39.
Six chiral diamide stationary phases (CSPs), namely N-(3-carbobenzoxypropionyl)-L-Val-tert-butylamide (CSP-1), N-undecenoyl-L-Val-S-α-phenylethylamide (CSP-2), N-undecenoyl-L-Val-R-α-phenylethylamide (CSP-3), OV-225-L-Val-tert-butylamide (CSP-4), XE-60-L-Val-tert-butylamide (CSP-5) and polycyanoethyl vinyl siloxane-L-Val-tert-butylamide (CSP-6), were inves-tigated and CSP-6 was crosslinked within narrow bore (70 μm) fused silica capillary columns. Theseparation of amino acid enantiomers on this narrow bore column by gas chromatography (GC) isillustrated. 相似文献
40.
Two new routes to hexafluorotropone have been developed, one from hexachlorotropone and a superior synthesis from hexafluorobenzene. Hexafluorotropone was found to be a very weak base, with a conjugate acid pK(a) of -6.2 +/- 0.5. The tropone adds in [6 + 4] fashion to cyclopentadiene and photocyclizes to hexafluorobicyclo[3.2.0]hepta-3,6-dien-2-one. Lithium hydroxide in benzene transforms the tropone into pentafluorotropolone, which functions as a bidentate ligand. 相似文献