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排序方式: 共有158条查询结果,搜索用时 187 毫秒
81.
D. A. Akimov A. A. Ivanov M. V. Alfimov S. N. Bagayev T. A. Birks W. J. Wadsworth P. St. J. Russell A. B. Fedotov V. S. Pivtsov A. A. Podshivalov A. M. Zheltikov 《JETP Letters》2001,74(9):460-463
Spectral superbroadening of subnanojoule femtosecond Cr:forsterite laser pulses is demonstrated for the first time in experiments with a tapered fiber. Coupling 40-fs 0.6-nJ pulses of 1.25-μm Cr:forsterite laser radiation into a tapered fiber with a taper waist diameter of about 2 μm and a taper waist length of 90 mm, we observed the spectra spanning more than two octaves at the output of the fiber. These experimental results open new horizons for the creation of compact femtosecond systems based on Cr:forsterite lasers and tapered fibers for optical metrology and biomedical applications. 相似文献
82.
E. S. Paul S. A. Forbes J. Gizon K. Hauschild I. M. Hibbert D. T. Joss P. J. Nolan B. M. Nyak J. A. Sampson A. T. Semple R. Wadsworth L. Walker J. N. Wilson L. Zolnai 《Nuclear Physics A》2001,690(4):855-354
The Doppler-Shift Attenuation Method has been used to extract transition quadrupole moments of high-spin bands in the N=74 isotones 133Pr, 132Ce and 131La, produced in the 37Cl + 100Mo reaction. The results appear to be configuration dependent and, for 133Pr and 132Ce, the involvement of Ω=1/2 νh9/2 and νf7/2 intruder orbitals appears to enhance the collectivity at high spin (I>25 ). 相似文献
83.
Adrian R. Wadsworth 《代数通讯》2013,41(8):863-872
84.
de Nobriga CE Hobbs GD Wadsworth WJ Knight JC Skryabin DV Samarelli A Sorel M De La Rue RM 《Optics letters》2010,35(23):3925-3927
In this Letter, we report group index measurements of the supermodes of an array of two strongly coupled silicon-on-insulator waveguides. We observe coupling-induced dispersion that is greater than the material and waveguide dispersion of the individual waveguides. We demonstrate that the system transforms from supporting the two supermodes associated with two coupled waveguides to the single mode of a slot waveguide within the investigated spectral range. During the cutoff of the antisymmetric supermode, an anti-crossing between the symmetric TM and antisymmetric TE supermodes has been observed. 相似文献
85.
D. Zhang G. Bhat S. Malkan L. Wadsworth 《Journal of Thermal Analysis and Calorimetry》1997,49(1):161-167
Polypropylene homopolymer (PP) and a copolymer (P/E) were processed using the Reicofil® spunbonding line at the Textiles and Nonwovens Development Center of the University of Tennessee, Knoxville. The properties of the filament samples taken before thermal-bonding were determined through a variety of techniques such as differential scanning calorimetry, thermomechanical analysis, thermal deformation analysis and mechanical properties. The two process variables investigated, primary air temperature and throughput had a strong influence on the structure and properties of both the filaments and the bonded nonwovens. As the primary air temperature and throughput decreased, there was a tendency for decrease in filament diameter with a simultaneous increase in their crystallinity, birefringence and thermal stability. The copolymer filaments showed lower crystallinity and orientation for all the corresponding processing conditions.Authors would like to thank the Exxon Chemical Company for funding a part of this study, for providing the polymers and for providing the spunbonding equipment at no cost to the University. 相似文献
86.
H. Hübel G. Baldsiefen R.M. Clark S.J. Asztalos J.A. Becker L. Bernstein M.A. Deleplanque R.M. Diamond P. Fallon I.M. Hibbert R. Krücken I.Y. Lee A.O. Macchiavelli R.W. MacLeod G. Schmid F.S. Stephens K. Vetter R. Wadsworth 《Zeitschrift für Physik A Hadrons and Nuclei》1997,358(2):237-238
The properties of the M1 bands in the Pb region are reviewed. They can be explained by ‘magnetic rotation’ which is a new concept in nuclear excitations. Spin and excitation energy along the bands are increased by the shears effect, a step-by-step alignment of large proton-particle and large neutron-hole spins into the direction of the total angular momentum. First evidence is presented for band termination connected with the closing of the shears. 相似文献
87.
88.
89.
Submicrometer axial resolution optical coherence tomography 总被引:7,自引:0,他引:7
Povazay B Bizheva K Unterhuber A Hermann B Sattmann H Fercher AF Drexler W Apolonski A Wadsworth WJ Knight JC Russell PS Vetterlein M Scherzer E 《Optics letters》2002,27(20):1800-1802
Optical coherence tomography (OCT) with unprecedented submicrometer axial resolution achieved by use of a photonic crystal fiber in combination with a compact sub-10-fs Ti:sapphire laser (Femtolasers Produktions) is demonstrated for what the authors believe is the first time. The emission spectrum ranges from 550 to 950 nm (lambda(c)=725 nm , P(out)=27 mW) , resulting in a free-space axial OCT resolution of ~0.75 mum , corresponding to ~0.5 mum in biological tissue. Submicrometer-resolution OCT is demonstrated in vitro on human colorectal adenocarcinoma cells HT-29. This novel light source has great potential for development of spectroscopic OCT because its spectrum covers the absorption bands of several biological chromophores. 相似文献
90.
A dispersion zero near 1300 nm of a narrow-diameter tapered fiber is used to generate broadband, near-infrared light. When femtosecond pulses at 1260 nm with 750 pJ of energy are launched in proximity to the second zero-dispersion wavelength, a continuum spanning 1000-1700 nm is produced. 相似文献