全文获取类型
收费全文 | 79篇 |
免费 | 2篇 |
专业分类
化学 | 16篇 |
综合类 | 2篇 |
数学 | 8篇 |
物理学 | 55篇 |
出版年
2014年 | 1篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 1篇 |
2007年 | 7篇 |
2006年 | 9篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有81条查询结果,搜索用时 81 毫秒
61.
Despite all the advances in nonlinear microscopy, all existing instruments are constrained to obtain images of one focal plane at a time. In this Letter we demonstrate a two-photon absorption fluorescence scanning microscope capable of imaging two focal planes simultaneously. This is accomplished by temporally demultiplexing the signal coming from two focal volumes at different sample depths. The scheme can be extended to three or more focal planes. 相似文献
62.
Planchon TA Amir W Field JJ Durfee CG Squier JA Rousseau P Albert O Mourou G 《Optics letters》2006,31(14):2214-2216
By using the third-harmonic signal generated at an air-dielectric interface, we demonstrate a novel way of correcting wavefront aberrations induced by high-numerical-aperture optics. The third harmonic is used as the input physical parameter of a genetic algorithm working in closed loop with a 37-actuator deformable mirror. This method is simple and reliable and can be used to correct aberrations of tightly focused beams, a regime where other methods have limitations. Improvement of the third-harmonic signal generated with an f/1.2 parabolic mirror by 1 order of magnitude is demonstrated. 相似文献
63.
Gibson EA Gaudiosi DM Kapteyn HC Jimenez R Kane S Huff R Durfee C Squier J 《Optics letters》2006,31(22):3363-3365
Efficient reflection grisms for pulse-compression and material-dispersion compensation have been designed and demonstrated in a 40 fs, 300 microJ, 5 kHz downchirped pulse amplification system for the first time to our knowledge. A grism design for 800 nm femtosecond laser pulse dispersion compensation applications is realized by using standard, commercial diffraction gratings. 相似文献
64.
65.
66.
67.
68.
69.
Koster S Duursma MC Boon JJ Nielen MW de Koster CG Heeren RM 《Journal of mass spectrometry : JMS》2000,35(6):739-748
The molecular structure of a series of homo- and copolyesters was studied using sustained off-resonance irradiation collisionally activation dissociation on a Fourier transform ion cyclotron resonance mass spectrometer. Electrospray ionization was used as an ionization technique. The most important fragmentation pathways of the homopolyesters poly(dipropoxylated bisphenol-A/adipic acid) and poly(dipropoxylated bisphenol-A/isophthalic acid) were studied. Six different dissociation mechanisms were observed which are very similar to the mechanisms found to occur during pyrolysis of these compounds. Four of these mechanisms are a result of cleavages of the ester bond and the others are due to cleavages of the ether bond or bisphenol-A unit. Some of the fragments expected are not present in the spectrum, indicating that each fragment has a specific sodium affinity. Sequence-specific fragments of two of the three copolyester sequences that theoretically can exist were experimentally observed. Fragments that originate from the third sequence are not unique and can also be formed from other sequences. Therefore, it was not possible to determine the presence of the third sequence. Copyright 2000 John Wiley & Sons, Ltd. 相似文献
70.