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991.
Diode pumped operation of 1 mm Tm,Ho:YAP microchip laser 总被引:1,自引:0,他引:1
A single-longitudinal-mode (SLM) operation of a c-cut 1 mm Tm(5%), Ho(0.3%):YAP micro-chip laser pumped by a fiber-coupled
diode-laser was reported. Under cryogenic temperature, the output power of 216 mW was obtained under the incident power of
2230 mW, corresponding to the slope efficiency was 13.6%. As much as 133 mW output and slope efficiency of 4.9% was obtained
under the pump power of 3000 mW at 291 K. In addition, a maximum SLM output power of 30 mW at wavelength of 2130.56 nm is
demonstrated under 77 K. 相似文献
992.
We report an experimental demonstration of muliwavelength erbium-doped fiber laser with adjustable wavelength number based
on a power-symmetric nonlinear optical loop mirror (NOLM) in a linear cavity. The intensity-dependent loss (IDL) induced by
the NOLM is used to suppress the mode competition and realize the stable multiwavelength oscillation. The controlling of the
wavelength number is achieved by adjusting the strength of IDL, which is dependent on the pump power. As the pump power increases
from 40 to 408 mW, 1–7 lasing line(s) at fixed wavelength around 1601 nm are obtained. The output power stability is also
investigated. The most power fluctuation of single wavelength is less than 0.9 dB, when the wavelength number is increased
from 1–7. 相似文献
993.
In this paper, we report two crystals Tm:YLF laser pumped by a fiber coupled diode laser with total power of 180 W at 792
nm. When the incident power reached up to 117.0 and 37.3 W of the emission wave-length at 1.91 μm was achieved. Through linear
fit, the corresponding slope efficiency of 38.5%, optical-to-optical conversion efficiency of 31.9% and the beam quality factor
of M
2 ∼ 1.1 were obtained, indicating nearly diffraction limited beam propagation. To our best knowledge, this is the best beam
quality among the reported paper results under the similar experiments. 相似文献
994.
A diode end-pumped single-frequency Tm,Ho:YAP laser at room temperature was reported. We obtain a single frequency Tm,Ho:YAP
laser of up to 31 mW with Fabry-Perot etalons in the cavity at 2130.8 nm. The optical conversion efficiency is 1.0% and the
slope efficiency is 6.3%. The measured full width at half maximum (FWHM) is approximately 65 pm. The single-longitudinal-mode
(SLM) laser can be used as a seed laser for coherent wind measurements and differential absorption LIDAR systems. 相似文献
995.
B. Q. Yao F. Chen C. T. Wu Q. Wang G. Li C. H. Zhang Y. Z. Wang Y. L. Ju 《Laser Physics》2011,21(3):468-471
In this paper, we presented experimental results concerning on the laser characteristics of two microchip lasers emitting
in the 2 μm range, Tm:Ho:YVO4 microchip laser and Tm:Ho:GdVO4 microchip laser. At a heat sink temperature of 283 K, the maximum output power of Tm:Ho:YVO4 laser and Tm:Ho:GdVO4 laser is 47 and 34 mW under absorbed pump power of 912 mW, respectively. High efficiency can be achieved for both lasers
at room temperature. Nevertheless, compared with Tm:Ho:GdVO4 laser, Tm:Ho:YVO4 laser can operate on single frequency with high power easily. At the heat sink temperature of 288 K, as much as 16.5 mW of
2052.3 nm single-longitudinal-mode (SLM) laser was achieved for Tm:Ho:YVO4 laser. Under the same condition, only 8 mW of 2048.5 nm SLM laser was achieved for Tm:Ho:GdVO4 laser. 相似文献
996.
B. Q. Yao F. Chen C. T. Wu Q. Wang G. Li C. H. Zhang Y. Z. Wang Y. L. Ju 《Laser Physics》2011,21(4):663-666
Room temperature Tm, Ho:YVO4 microchip laser operated around 2 μm was demonstrated for the first time to our knowledge. At a heat sink temperature of
283 K, a maximum output power of 47 mW was obtained by using a 0.25 mm length crystal at an absorbed pump power of 912 mW,
corresponding to a slope efficiency of 9.1%. Increasing the temperature to 288 K, as much as 16.5 mW 2052.3 nm single-longitudinal-mode
laser was achieved. The M
2 factor was measured to be 1.4. 相似文献
997.
A novel artificial anion receptor based on phenylhydrazone structure was designed, synthesized and characterized. The binding behavior of the receptor to various anions was investigated by UV-vis fluorescence analyses. In addition, 1H NMR experiments were carried out to explore the nature of interaction between receptor 1 and acetate. The processes of sensing can literally be seen through the ‘naked-eye’ for the sharp color changes from yellow to purple. 相似文献
998.
An information hiding method based on the optical interference principle is proposed. In this method, a secret image can be obtained by two light beams' interference. One of the beams is modulated by our assigned host image; and the other is modulated by a noise-like complex distribution, which is regard as the encrypted image. The transmission of the encrypted image can be implemented by hiding it in the host image to prevent the communication from being perceived by unauthorized person. In addition, this method can also realize simultaneous encryption and hiding for two images. A series of numerical simulation results are presented to verify the feasibility of our proposed method. 相似文献
999.
We report a new type of black silicon: flexible black silicon. A silicon-on-insulator (SOI) wafer is irradiated by automatically scanning a femtosecond laser and then split by etching out the SOI silica middle layer. Large-area, uniform micro spikes on the surface of a very thin flexible silicon layer are obtained. The black silicon shows good flexibility and optical properties. The absorption spectrum of the flexible black silicon is as high as 97% in the visible and insensitive to the change of the incident angle of the light, which makes it a potential good candidate as an absorber for the solar-thermo generator. 相似文献
1000.
Chunting Wu Youlun Ju Qiang Wang Zhenguo Wang Baoquan Yao Yuezhu Wang 《Optics Communications》2011,284(4):994-998
The solid-state, tunable, narrowband, high pulse energy and high reliability lasers are attractive source for LIDAR system. In this paper, we demonstrated a diode pumped injection-seeded 2 μm Tm:YAG laser. By inserting two F-P etalons into the laser cavity, linear-polarized single-frequency seed-laser was achieved at a wavelength of 2013 nm, with a maximum output power of 60 mW. Long-term and short-term frequency stability for the seed-laser were 1.27 × 10− 7 and 97 Hz/μs, respectively. High power Q-switched laser was operated using a bowtie cavity, the bidirectional output of which was favorable for the injection-seeded. After injecting the seed-laser to the power-laser, single-frequency, nearly transform-limited pulsed 2 μm laser was obtained. As much as 2.0 mJ output energy was achieved at an operating repetition rate of 15 Hz, with a pulse width of 356.2 ns. 相似文献