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71.
Performance scaling of passively mode-locked ultrashort-pulse fiber oscillators in terms of average power, peak power, and pulse energy is demonstrated. A very-large-mode-area fiber laser in an all-positive group-velocity-dispersion ring cavity configuration with intracavity spectral filter, mode-locked by nonlinear polarization evolution, emits 66 W of average power at 76 MHz repetition rate, corresponding to 0.9 μJ pulse energy. The pulses are dechirped to 91 fs outside the cavity with an average power of 60 W remaining after the compressor. The generated pulse peak power is as high as 7 MW. 相似文献
72.
In this work, the PGD method will be considered for solving some problems of fluid mechanics by looking for the solution as a sum of tensor product functions. In the first stage, the equations of Stokes and Burgers will be solved. Then, we will solve the Navier–Stokes problem in the case of the lid-driven cavity for different Reynolds numbers (Re = 100, 1000 and 10,000). Finally, the PGD method will be compared to the standard resolution technique, both in terms of CPU time and accuracy. 相似文献
73.
Marcelo M. Cavalcanti Ammar Khemmoudj Mohamed Medjden 《Journal of Mathematical Analysis and Applications》2007,328(2):900-930
In this paper, the uniform stabilization of the Cauchy-Ventcel problem with variable coefficients is considered, and the uniform energy decay rate for the problem is established by Riemannian geometry methods. 相似文献
74.
We evaluate the inter-channel crosstalk in a semiconductor optical amplifier when injecting a high optical power continuous wave, as assist light, inside its active region around the gain transparency wavelength. In this work, the crosstalk of signal1 (1535 nm) modulated at 2.5 Gb/s, has been induced by signal2 (1560 nm) modulated at 2.5 Gb/s as well and having an optical input power of −7.5 dBm to simulate a multi-channel transmission. By measuring the bit error rate of signal1, we show that the pattern penalty induced by the cross-gain modulation can be significantly reduced or even in certain conditions suppressed by the assist light. 相似文献
75.
Ammar R Baringer P Coppage D Davis R Haas P Kelly M Kwak N Lam H Ro S Kubota Y Nelson JK Perticone D Poling R Schrenk S Crawford G Fulton R Jensen T Johnson D Kagan H Kass R Malchow R Morrow F Whitmore J Wilson P Bortoletto D Brown DN Dominick J McIlwain RL Miller DH Modesitt M Ng CR Schaffner SF Shibata EI Shipsey IP Battle M Kroha H Sparks K Thorndike EH Wang C Alam MS Kim IJ Li WC Nemati B Romero V Sun CR Wang P Zoeller MM Goldberg M Haupt T Horwitz N Jain V Kennett R Mestayer MD Moneti GC 《Physical review D: Particles and fields》1991,44(11):3383-3393
76.
Ammar R Baringer P Coppage D Davis R Kelly M Kwak N Lam H Ro S Kubota Y Lattery M Nelson JK Perticone D Poling R Schrenk S Wang R Alam MS Kim IJ Nemati B Romero V Sun CR Wang P Zoeller MM Crawford G Fulton R Gan KK Kagan H Kass R Lee J Malchow R Morrow F Sung MK Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Skubic P Snow J Bortoletto D Brown DN Dominick J McIlwain RL Miller DH Modesitt M Shibata EI Schaffner SF Shipsey IP Battle M Ernst J Kroha H Roberts S Sparks K Thorndike EH 《Physical review D: Particles and fields》1992,45(11):3976-3985
77.
Alexander J Artuso M Bebek C Berkelman K Browder T Cassel DG Cheu E Coffman DM Crawford G DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Katayama N Kreinick DL Lewis JD Ludwig GS Mistry NB Mueller J Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Selen M Silverman A Stone S Worden H Worris M Sadoff AJ Avery P Besson D Garren L Yelton J Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Zhu Y 《Physical review letters》1990,65(13):1531-1534
78.
Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Ammar R Baringer P Coppage D Haas P Lam H Jawahery A Park CH Kubota Y Nelson JK Perticone D Poling R Chen W Dominick J McIlwain RL Miller DH Ng CR Schaffner SF Shibata EI Yao W Sparks K Thorndike EH Alam MS Kim IJ Li WC Lou XC Sun CR Fulton R Hempstead M Jensen T Johnson DR Kagan H Kass R Morrow F Whitmore J Bortoletto D Goldberg M Horwitz N Mestayer MD Moneti GC Sharma V Shipsey IP Skwarnicki T Csorna SE Letson T Alexander J 《Physical review D: Particles and fields》1990,41(3):805-808
79.
1,3-Diphenyl-5-imino-2-imidazolidinone-4-thione (II) was treated with diazomethanes to give (III-V). Interaction of (II) with amino compounds furnished the corresponding 4-substituted imino derivatives (VIa-m). Imidazoquinoxaline derivatives (VIIIb, c) were obtained through interaction of (II) with o-phenylenediamines. Condensation of (II) with hydrazines afforded the hydrazones (IX, Xa, b). Semicarbazone and thiosemicarbazone derivatives (XIIa-d) were prepared from the reaction of (IX) with isocyanates and isothiocyanates. Again (II) was allowed to react with n-butylmagnesium bromide and HgCl2 to give (XIII) and (XIV) respectively. 相似文献
80.
Mohamed S.A. El-Gaby Jehan A. Micky Nadia M. Saleh Yousry A. Ammar Heba S.A. Mohamed 《中国化学快报》2015,26(6):690-694
2-Aminocyclopenta[d]pyrimidines 3a-c were achieved via a one-pot, three-component reactions of cyclopentanone 1, aromatic aldehyde and guanidine hydrochloride (1:2:1 molar ratio). Also, cyclization of 2,5-bis-(arylmethylidene)cyclopentanones 2 with guanidine hydrochloride (1:1 molar ratio) in methanol in the presence of sodiummethoxide afforded cyclopenta-[d]pyrimidines 3. Compound 3a has been shown to be a useful building block for the synthesis of some novel pyrimido[1,2-a]pyrimidines 5, 7 and 12. The structures of the newly synthesized compounds were confirmed on the basis of analytical and spectral data. 相似文献