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101.
102.
CHENG Xiang 《半导体光子学与技术》2004,(4)
Amorphous carbon (a-C) films and amorphous carbon films incorporating with the nitrogen (a-C∶N) were deposited on silicon substrates in a radio-frequency driven plasma enhanced chemical vapour deposition system, while the surface electrical properties of films were investigated by electrochemical capacitance-voltage measurements. It was examined the effect of the interface defects on the properties and deduced that the conducting type of a-C∶N films was n-type. Subsequently, a comparative studies of a-C and a-C∶N films were performed by photoluminescence spectra depending on the temperature. With the decrease of the temperature, the main band with peak energy of 2.48 eV in the a-C∶N films was more intense compared with the other three bands caused by amorphous C in the a-C films. 相似文献
103.
104.
In this paper, the data of wax precipitation before and after the addition of the additives showed that the addition of the drag reducing agent (DRA) and the pour point depressant (PPD) cannot change the wax appearance temperature (WAT) of crude oil. When the dosage of DRA is small, the DRA cannot increase, stop, or slow down the precipitation of wax crystals. The addition of PPDs has no influence on the amount of precipitated wax crystals. From the GPC analysis, the molecular weight of the wax deposit samples in Linpu pipeline is from 500 to 76,800, which indicates that there is no enrichment of DRA in wax deposit samples. The results of IR show that the C?O group was not detected in the wax deposit sample of the Wei Jing pipeline, which indicates that there is no enrichment of the PPDs in wax deposit samples. The results showed that the DRA and PPD have no obvious effect on crude oil pipeline wax deposition. 相似文献
105.
The coked Mo-Co/γ-Al2O3 catalysts were Soxhlet extracted with the solvent of tetrahydrofuran. Experimental techniques like FT-IR, GC-MS, XPS, H2-TPR, BET, etc. were applied for the characterization of coke and catalysts to make a comparison of their physical properties. The results showed that the active components of the catalyst were slightly less after the reaction. The specific surface area and the pore volume had recovered to some degree. These results indicated that the main cause of deactivation of Mo-Co/γ-Al2O3 catalysts is carbon deposit. The principal components of the soluble carbon deposit on Mo-Co/γ-Al2O3 catalysts were alkyl aromatics with 1–4 rings and C19–C29 long-chain alkane compounds. 相似文献
106.
Xiaoli Xu Richard T. Kuehn Mehmet C. Öztürk Jimmie J. Wortman Robert J. Nemanich Gari S. Harris Dennis M. Maher 《Journal of Electronic Materials》1993,22(3):335-339
Various silicon surface cleaning processes for rapid thermal in-situ polysilicon/ oxide/silicon stacked gate structures have
been evaluated. Metal-oxide-semiconductor capacitors were fabricated to assess the effects of cleaning on the quality of gate
oxide structures produced by both rapid thermal oxidation (RTO) and rapid thermal chemical vapor deposition (RTCVD). Excellent
electrical properties have been achieved for both RTO and RTCVD gate oxides formed on silicon wafers using either an ultraviole/zone
(UV/O3) treatment or a modified RCA clean. On the contrary, poor electrical properties have been observed for RTO and RTCVD gate
oxides formed on silicon wafers using a high temperature bake in Ar, H2, or high vacuum ambient. It has also been found that the electrical properties of the RTCVD gate oxides exhibit less dependence
upon cleaning conditions than those of RTO gate oxides. This work demonstrates that initial surface condition prior to gate
oxide formation plays an important role in determining the quality of RTO and RTCVD gate oxides. 相似文献
107.
该文将光学模拟技术与镀膜工艺结合,采用光线追踪程序来模拟溅射粒子在振子表面膜层的分布状态。通过模拟和相关实验验证,当设备相对角度β=10°、φ=60°时,振子表面膜层的均匀性最高,模拟值与实际测试值匹配度较好,误差在7%以内。 相似文献
108.
M. R. Islam R. V. Chelakaea J. G. Neff K. G. Fertitta P. A. Grudowski A. L. Holmes F. J. Ciuba R. D. Dupuis J. E. Fouquet 《Journal of Electronic Materials》1995,24(6):787-792
AlGaAs double heterostructures are grown by low-pressure metalorganic chemical vapor deposition to evaluate the level of oxygen
contamination in different trimethylaluminum sources. Effects of arsine purifiers, misoriented substrates, atmospheric exposure
of the growth chamber, and possible phosphorus contamination are also studied. Extensive characterization is performed on
these films by a variety of methods, including high-resolution x-ray diffraction, photoluminescence (PL), time-resolved photoluminescence,
and secondary-ion mass spectrometry. The PL intensities for structures grown with the low-alkoxide grade are reproducibly
much greater than those grown with the regular-grade TMA1. The use of AsH3 purification improves the PL intensity. 相似文献
109.
Thin strained regions have been inserted at the interfaces of lattice-matched InGaAs/lnP superlattices to assess growth conditions
for tailoring of localized compositional changes and for studying As-P intermixing behavior during heterojunction growth.
Also, precise growth rates of binary composition layers were determined from specially designed superlattices using strained
layers of common anion compounds inserted periodically into InP and GaAs. Growth rates of fractional monolayers are found
to be identical to thick layer growth rates. When thin InAs, GaAs, GaP, ALAs, or AIP layers were inserted at the InGaAs/lnP
heterojunctions, the measured strain at either one or both interfaces was equal to the strain predicted from the growth rate
x time product. Excess strain seen in some cases is due to a change in As-P intermixing and this component can be separated
from the predicted strain. Insertion of Ga-compounds at the InP-grown-on-InGaAs interface causes interface roughening which
degrades the superlattice. For all other compositions the thin, highly strained regions are not detrimental to the crystalline
quality of the periodic structure. 相似文献
110.