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91.
High-energy, high-power ytterbium-doped Q-switched fiber laser 总被引:8,自引:0,他引:8
Alvarez-Chavez JA Offerhaus HL Nilsson J Turner PW Clarkson WA Richardson DJ 《Optics letters》2000,25(1):37-39
We report on a Q -switched, cladding-pumped, ytterbium-doped large-mode-area fiber laser operating at 1090 nm that is capable of generating 2.3 mJ of output pulse energy at a 500-Hz repetition rate and more than 5 W of average output power at higher repetition rates in a high-brightness beam (M(2) = 3) . Using a similar fiber with a smaller core, we generated >0.5-mJ pulses in a diffraction-limited beam. Our results represent a threefold increase in pulse energy over previously published values for Q-switched fiber lasers and firmly establish fiber lasers as compact, multiwatt, multimillijoule pulse sources with large scope for both industrial and scientific applications. 相似文献
92.
Albanis V Bratfalean RT Dhanjal S Zheludev NI Emel'yanov VI Petropoulos P Richardson DJ 《Optics letters》2000,25(21):1594-1596
The reflectivity of a gallium/silica interface formed on an optical flat or at the tip of a cleaved optical fiber can be reduced in a reversible fashion when the interface is excited by a few milliwatts of laser power. This phenomenon occurs at temperatures just below gallium's melting point. We believe that the effect can be attributed to light-induced structuring at the interface. 相似文献
93.
We present a new approach for the simulation of beyond standard model (BSM) physics within the Herwig++ event generator. Our
approach is more generic than previous methods with the aim of minimising the effort of implementing further new physics models.
Spin correlations, which are important for BSM models due to new heavy fermions and bosons, are discussed and their effects
demonstrated for the minimal supersymmetric standard model (MSSM) and Randall–Sundrum model using our new framework. 相似文献
94.
Zhi NA Bei JIANG Hui YANG Zhong Wen LIN Han Dong SUN* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming Chemistry Deparment of the College of Life Science Chemistry Yunnan University K 《中国化学快报》2001,(8)
Isodon enanderianus (Hand. -Mazz.) H. W. Li, has been used in folk medicine as anti-inflammatory and detoxified agent1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. In order to find more biologically active substances, we have carefully investigated the chemical constituents of I. enanderianus collected in Shiping county of Yunnan province, and as a result, enanderi… 相似文献
95.
X-ray diffraction has been used to study the nematic phases of the cis and trans isomers of an elongated molecule containing the cyclobutane group. It has been shown that these nematic phases consist of a mixture of single molecules and overlapping core dimers. It has been found that increasing the temperature of the cis isomer rapidly reduces the dimer population, whereas increasing the temperature of the trans isomer enhances the dimer population. This provides an explanation of the relatively high clearing temperature of the trans isomer. The different temperature dependences of the dimer population in the cis and trans isomers has been explained by a model involving inversion of the cylobutane group. 相似文献
96.
E. G. Richardson 《Colloid and polymer science》1937,81(1):87-88
Zusammenfassung Mit Bezug auf kürzlich in der Kolloid-Zeitschrift veröffentlichte Arbeiten wird die Theorie der Analyse der Partikelgröße mittels Sedimentation und Photozelle diskutiert. Es wird darauf hingewiesen, daß der Verfasser schon im Jahre 1934 einen ähnlichen Apparat beschrieben hat. Es wird gezeigt, wie man eine ununterbrochene Verteilungskurve der Partikeldurchmesser eines Dispersoids bekommen kann.Übersetzt von H. A. Wannow (Leipzig). 相似文献
97.
98.
J. Badier M. Bardadin-Otwinowska C. Bemporad U. Berthon H. Bienvenu J. Boucrot J. Bourotte G. Burgun O. Callot Ph. Charpentier A. M. Cnops M. Cohen F. Constantini M. Crozon D. Décamp P. Delpierre J. F. Detoeuf P. Espigat B. Gandois G. R. Giannini V. Hajjar M. Hansroul Y. Karyotakis P. Lariccia P. Le D? J. Mas A. Michelini G. C. Moneti M. Moniez E. Paré G. Rahal-Callot M. Rumpf O. Runolfsson A. Tilquin S. Weisz NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,31(3):341-347
Direct photon production has been studied by an experiment performed with the NA3 spectrometer at CERN, using incident negative and positive beams at 200 GeV/c interacting with an isoscalar Carbon target. Two different triggers have been used; one of them requires the photon conversion. The experiment is sensitive to direct photons produced with 3.0≦P T ≦6 GeV/c and center-of-mass rapidity ?0.4≦y *≦1.2. Inclusive cross sections are given for incident π± and protons, and compared with second order QCD predictions; finally an estimation of the gluon structure function of the nucleon is given. 相似文献
99.
100.
Jonathan P. Williams Julie Ann Lough Iain Campuzano Keith Richardson Peter J. Sadler 《Rapid communications in mass spectrometry : RCM》2009,23(22):3563-3569
We report the development of an enhanced algorithm for the calculation of collision cross‐sections in combination with Travelling‐Wave ion mobility mass spectrometry technology and its optimisation and evaluation through the analysis of an organoruthenium anticancer complex [(η6‐biphenyl)RuII(en)Cl]+. Excellent agreement was obtained between the experimentally determined and theoretically determined collision cross‐sections of the complex and its major product ion formed via collision‐induced dissociation. Collision cross‐sections were also experimentally determined for adducts of this ruthenium complex with the single‐stranded oligonucleotide hexamer d(CACGTG). Ion mobility tandem mass spectrometry measurements have allowed the binding sites for ruthenium on the oligonucleotide to be determined. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献