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851.
Yao Chun-Hsu Chang Tung-Hao Tsai Min-Jia Lai Yuan-Chun Chen Yi-An Chang Yuan-Jen Chen Chin-Hsing 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(2):1277-1286
Volumetric modulated arc therapy (VMAT) was developed to shorten treatment time and increase target conformance. However, a true three-dimensional (3D) gel dosimeter is needed for dose verification. In this study, two clinic cases were adopted: a simple case of lung cancer and a complex case of larynx cancer. For each clinic case, two treatment plans were generated for the same planning target volume using VMAT and intensity modulated radiation therapy calculation software packages. An N-isopropylacrylamide (NIPAM) polymer gel dosimeter was used for 3D dose verification. In addition, the dose characteristics of the NIPAM gel dosimeter were investigated for the two clinic cases.
相似文献852.
853.
Wei-Hsiao Lin Chien-Jang Wu Shoou-Jinn Chang 《Applied Physics A: Materials Science & Processing》2011,104(3):807-809
In this work, we investigate the angular dependence of transmission and reflection in the single-negative (SNG) materials.
We consider a model structure of a SNG bilayer which consists of the epsilon-negative (ENG) and mu-negative (MNG) layers.
The wave transmission and reflection properties due to the losses from the ENG and MNG materials are specifically investigated.
With the presence of losses in the ENG and MNG materials, some unusual wave properties will be explored and numerically demonstrated. 相似文献
854.
855.
856.
A plasmonic multilayer structure (PMS) is proposed for photovoltaic cells with an ultrathin active layer that is 30 nm amorphous
Si (α-Si). The optical properties of the PMS are analyzed by rigorous coupled-wave analysis (RCWA) and finite-difference time-domain
(FDTD) method. Using the PMS, the incident light can be trapped into localized surface plasmon (LSP) and then the localized
surface plasmon induces the surface plasmon (SP) that propagates transversely within the α-Si layer. Compared with the indium tin oxide (ITO)/α-Si/Ag structure, the photon number absorbed by PMS increase 28.7% while a normal incident transverse magnetic (TM) polarization
wave is applied. 相似文献
857.
K. Zhou H. P. Wang J. Chang B. Wei 《Applied Physics A: Materials Science & Processing》2011,105(1):211-214
Thermophysical properties of liquid alloys are usually difficult to measure, especially for high melting point and reactive
alloys. In this work, the surface tensions of superheated and undercooled liquid Ti55Al45, Ti50Al45Nb5 and Ti45Al45Nb10 alloys are determined by using oscillating drop method under electromagnetic levitation state. The experimental results of
Ti–Al and Ti–Al–Nb alloys display linear temperature dependence. The maximum undercoolings of 259 (0.143T
L), 268 (0.146T
L) and 275 K (0.147T
L) are respectively achieved for these three alloys. Furthermore, the viscosities of liquid Ti55−x
Al45Nb
x
alloys are also derived from the experimental results. 相似文献
858.
The nonisothermal decomposition kinetics of Ginkgo biloba leaves polyprenol (GBP) and cleaved situation of its chemical bond during thermal decomposition process were first investigated using thermogravimetric (TG) and TG‐FTIR technology. The results of thermal decomposition kinetics revealed that the nonisothermal decomposition mechanism of GBP corresponds to first‐order chemical reaction with n = 1, integral form g(a) = –ln(1 – a) and differential form f(a) = 1 – a. TG‐FTIR results demonstrated that absorbance of –CH3, unsaturated C–H bond, =CH2, accumulated C=C, –OH, and so on constantly increased with thermal decomposition reaction went on. In addition, storage life of GBP was also evaluated. These data could provide theoretical guidance for purification under high temperature and other thermal application of GBP. 相似文献
859.
S. P. Changlai H. H. Tsai S. C. Tsai H. P. Chen C. L. Chang Y. H. Yao C. Y. Chen 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):859-863
This work is the first evaluation of environmental gamma exposure rates by the Nuclear Medicine Department at Lin Shin Hospital
(LSH) in Taichung with Thermoluminescent dosimeter (TLD-100H) during the Fukushima Nuclear Power Plant (FNPP) accident. After
the 9.0 MW strong earthquake hit northern Japan on March 11, 2011, a TLD-100H was used to monitor environmental kerma rate at Taichung
(2,500 km away from northern Japan) from Mar-08 to Apr-09, 2011 and evaluated kerma rate due to global fallout of the sever
FNPP accidents. Exposure rates varied widely among positions close to the PET/CT facility. Observed kerma rates of up to 4.12 ± 0.62 mSv mo−1 indicated an explicit, heavy leakage of photon through the PET/CT facility. No significant contributions were detected at
Taichung, Taiwan. Hence, the health effect cause by the “extra radiation” from FNPP accidents is negligible. As this was a
rare case of environmental monitoring during a nuclear power plant accident, its findings are of considerable significance. 相似文献
860.