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991.
H. R. Vydyanath J. A. Ellsworth R. F. Fisher J. J. Kennedy C. J. Johnson G. T. Neugebauer 《Journal of Electronic Materials》1993,22(8):1067-1071
Cd1−xZnxTe compounds of different compositions have been prepared at temperatures ranging from 400 to 1000°C by annealing elemental
Te in sealed quartz ampoules, in an atmosphere comprising vapors of Cd and Zn whose partial pressures were varied by varying
the composition of the binary Cd1−yZny alloys which provided the Cd and Zn vapors in these annealing experiments. The chemical compositions of the resulting Cd1−xZnxTe compounds have been analyzed using electron probe microanalytical techniques. Results indicate that presence of a 0.5%Zn
along with Cd in a closed or semi-closed system may prove to be beneficial in preventing decomposition and/or formation of
a metal/non metal phase during annealing of Cd0.96Zn0.04 Te substrates. Using the thermodynamic data in the literature for the binary Cd1−yZny alloys and with the assumption that the activities of the Cd and Zn components are weakly dependent on temperature, the partial
pressures of Cd and Zn in equilibrium with the Cd1−xZnxTe compounds at various temperatures have been evaluated. 相似文献
992.
高剂量Ar离子辐照Si缺陷产生及其退火行为EPR研究 总被引:2,自引:1,他引:1
112MeVAr离子在50K以下的低温辐照Si到8×1014/cm2剂量,室温下采用电子顺磁共振技术分析了由辐照引起的缺陷产生及其退火行为,结果表明:Ar离子辐照在Si中引起了中性四空位(Si-P3心)、带正电荷的〈100〉劈裂的双间隙子(Si-P6心)以及连续的非晶层3种缺陷的形成. 在200℃的退火温度,Si-P3心和Si-P6心消失,这时带负电荷的五空位(Si-P1心)开始生长,Si-P1心可以保持到550℃左右的退火温度. 在350℃时,可以明显地观测到另一个含有更多空位的顺磁缺陷心(Si-A11心).连续非晶层的再结晶需要600℃以上的温度,并且在整个退火过程中,非晶顺磁共振线的线型和线宽保持不变. 定性地讨论了结果. 相似文献
993.
Pt/n-GaN肖特基接触的退火行为 总被引:2,自引:1,他引:1
在金属有机物气相外延 (MOVPE)方法生长的非故意掺杂的n GaN上用Pt制成了肖特基接触 ,并在 2 5 0~6 5 0℃范围内对该接触进行退火 .通过实验发现 ,Pt与非故意掺杂n GaN外延薄膜可以形成较好的肖特基接触 ,而适当的退火温度可以有效地改善Pt/n GaN肖特基接触的性质 .在该实验条件下 ,40 0℃温度下退火后的Pt/n GaN肖特基接触 ,势垒高度最大 ,理想因子最小 .在 6 0 0℃以上温度退火后 ,该接触特性受到破坏 ,SEM显示在该温度下 ,Pt已经在GaN表面凝聚成球 ,表面形成孔洞. 相似文献
994.
The effects of thermal annealing on the component and microstructure of carbon nitride films deposited by vacuum cathodic arc method are reported. The bonding structure of the films is investigated by Raman spectroscopy, FTIR, XPS and valence band XPS. Upon annealing, the N content of the film drops gradually from original 31.0 to 17.0 at.% at 600 °C. The results of Raman spectroscopy, FTIR and valence XPS demonstrate that the films below 500 °C mainly consist of aromatic cluster component and polymeric component, which is rather stable upon the increasing of anealing temperatures. With the further increasing of the annealing temperatures from 400 to 600 °C, the fraction of polymeric component decreases and the aromatic component develops greatly. Meanwhile the films tend to transform towards the fullerene-like microstructure, which can be seen from the large separation of the N 1s peaks (>2.0 eV). As a result the N sp3 C bonds increase due to the rising of cross-linking between the graphite plane. 相似文献
995.
996.
Annealing behaviour of structure and morphology and its effects on the optical gain of Er3+/Yb3+ co-doped Al2O3 planar waveguide amplifier
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Using transmission electron microscopy (TEM) and x-ray diffraction
analysis, we have studied the structural and morphological evolution
of highly Er/Yb co-doped Al2O3 films in the temperature
range from $600\,^{\circ}\mkern-1mu$C--900$\,^{\circ}\mkern-1mu$C.
By comparison with TEM observation, the annealing behaviours of
photoluminescence (PL) emission and optical loss were found to have
relation to the structure and morphology. The increase of PL
intensity and optical loss above 800$\,^{\circ}\mkern-1mu$C might
result from the crystallization of amorphous Al2O3 films.
Based on the study on the structure and morphology, a rate equation
propagation model of a multilevel system was used to calculate the
optical gains of Er-doped Al2O3 planar waveguide
amplifiers involving the variation of PL efficiency and optical loss
with annealing temperature. It was found that the amplifiers had an
optimized optical gain at the temperature corresponding to the
minimum of optical loss, rather than at the temperature
corresponding to the maximum of PL efficiency, suggesting
that the optical loss is a key factor for determining the optical gain of an
Er-doped Al2O3 planar waveguide amplifier. 相似文献
997.
998.
Katsufumi Tanaka Yuichiro Tanabe Takatoshi Morina Ryuichi Akiyama 《Liquid crystals》2008,35(3):253-264
Solid cast films with polydomain textures were prepared on a glass substrate with transparent interdigitated electrodes from an isotropic aqueous solution of hydroxypropyl cellulose via its liquid crystalline phase under the sinusoidal electric field with small amplitude and frequency of 0.05 V µm-1 and 105 Hz, respectively. The process was monitored using microdielectrometry as well as polarised optical microscopy. The apparent dielectric constant εr' and loss factor εr' sensitively changed with time depending on the process conditions. On the other hand, the logarithmic relation between εr' and εr' showed a single curve, when they were normalised by an effective portion of the electrostatic energy density estimated using each solid-film thickness. The conversion to the solid film was estimated during the process based on the concentration dependences of εr' and εr'. Characteristic times were reported for the onset of the biphasic phase, fully developed cholesteric phase and termination of the process. 相似文献
999.
This paper presents a mathematical model and simulated annealing based solution approach for finding optimal location updates and paging area configuration for mobile communication networks. We use a two-layered zone-based location registration and paging scheme in which the costs of location updates and paging signaling traffic are reduced by introducing a two-step paging process. The location updates and paging procedures in a two-layered scheme are first described, and an approximation of the measure required for calculating the paging-related signaling volume is provided based on assumptions of cell shapes and mobile stations’ movement patterns. A simulated annealing (SA)-based solution method is devised along with a greedy heuristic, and computational experiments are conducted to illustrate the superiority of the proposed SA-based method over other solution methods. 相似文献
1000.
Temperature control and wafer-to-wafer reproducibility during momentary annealing via rapid thermal annealing is critical
for TiSi2
Self-Aligned siLICIDE (SALICIDE) processing for deep submicron complementary metal oxide semiconductor. TiSi2 must undergo a transformation from the high resistivity C49 phase to the low resistivity C54 phase for applications where
it is used as a gate conductor. A process modification to achieve improved wafer-to-wafer and within wafer temperature reproducibility
is demonstrated. It has the additional benefit to the TiSi2 salicide process of enabling anneals of reduced duration, enhancing suicide transformation to the desired phase without leading
to agglomeration. 相似文献