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41.
Ying-Yu Kuo Wai-Tim Jim Liang-Cheng Su Chi-Jung Chung Ching-Yu Lin Chieh Huo Jen-Chih Tseng Shih-Han Huang Chih-Jen Lai Bo-Chih Chen Bi-Juan Wang Tzu-Min Chan Hui-Ping Lin Wun-Shaing Wayne Chang Chuang-Rung Chang Chih-Pin Chuu 《International journal of molecular sciences》2015,16(5):10748-10766
Head and neck cancers, which affect 650,000 people and cause 350,000 deaths per year, is the sixth leading cancer by cancer incidence and eighth by cancer-related death worldwide. Oral cancer is the most common type of head and neck cancer. More than 90% of oral cancers are oral and oropharyngeal squamous cell carcinoma (OSCC). The overall five-year survival rate of OSCC patients is approximately 63%, which is due to the low response rate to current therapeutic drugs. In this review we discuss the possibility of using caffeic acid phenethyl ester (CAPE) as an alternative treatment for oral cancer. CAPE is a strong antioxidant extracted from honeybee hive propolis. Recent studies indicate that CAPE treatment can effectively suppress the proliferation, survival, and metastasis of oral cancer cells. CAPE treatment inhibits Akt signaling, cell cycle regulatory proteins, NF-κB function, as well as activity of matrix metalloproteinase (MMPs), epidermal growth factor receptor (EGFR), and Cyclooxygenase-2 (COX-2). Therefore, CAPE treatment induces cell cycle arrest and apoptosis in oral cancer cells. According to the evidence that aberrations in the EGFR/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling, NF-κB function, COX-2 activity, and MMPs activity are frequently found in oral cancers, and that the phosphorylation of Akt, EGFR, and COX-2 correlates to oral cancer patient survival and clinical progression, we believe that CAPE treatment will be useful for treatment of advanced oral cancer patients. 相似文献
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The effect of manganese sulfide (MnS) inclusions on the machinability of free-cutting steel is based on their morphology, size and distribution. Furthermore, the plasticity of MnS is high during the hot working caused different characterization of MnS. In this study, the deformation behavior of MnS in 1215MS steel after a thermomechanical process was investigated at 1323 K. The microstructures of MnS inclusions were characterized by optical microscopy, scanning electron microscopy, energy-dispersive spectrometry, and electron backscattering diffraction (EBSD). As the thickness reduction of the inclusions increased from 10 to 70%, their average aspect ratio increased from 1.20 to 2.39. In addition, the deformability of MnS inclusions was lower than that of the matrix. The possible slip systems of A, B, C, and D plane traces were \(\left( {\bar{1}0\bar{1}} \right)\left[ {\bar{1}01} \right],\left( {10\bar{1}} \right)\left[ {101} \right],\left( {011} \right)\left[ {01\bar{1}} \right]\), and \(\left( {110} \right)\left[ {1\bar{1}0} \right]\). Furthermore, the EBSD measurements suggested that slip planes in MnS inclusions occur on {110} planes. 相似文献
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In their original forms, carbon nanotubes (CNT) are spatially entangled. To make CNT papers (CNTPs), the CNT agglomerates must be dispersed and re‐entangled into a planar sheet. The processing characteristics are very different from those of traditional buck‐form nanocomposites. This article examines the processing, micro‐structures, and failure behavior of the CNTP composites. The CNTPs were first made by a dispersion and filtering process. Then, an epoxy resin was added into the CNTP by using a vacuum bag method. Different CNT weights were employed to make the CNTPs with different thicknesses and areal weights. The CNTP allows direct resin impregnation along the thickness direction and avoids the difficulty of dispersing CNTs in the viscous resin. The CNT content can be much higher than that attainable in traditional bulk CNT composites. Both tensile and tearing tests were conducted, and the fracture behaviors were examined. POLYM. COMPOS., 37:1564–1571, 2016. © 2014 Society of Plastics Engineers 相似文献
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Planar Heterojunction Perovskite Solar Cells Incorporating Metal–Organic Framework Nanocrystals 下载免费PDF全文
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Artificial Photosynthesis: Ni‐Nanocluster Modified Black TiO2 with Dual Active Sites for Selective Photocatalytic CO2 Reduction (Small 2/2018) 下载免费PDF全文
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Mobile Networks and Applications - There is a tremendous growth in the traffic of the Internet of Things (IoT) devices. Some of the IoT application scenarios may prefer the wireless access... 相似文献
49.
Soiling problems are always encountered for equipment installed in outdoor environments, such as headlamps of automobiles, air conditioners, solar collectors, and so on. How to prevent soiling problems on this equipment is one of the challenges for the design of their external layouts. Thus, evaluations of the dust sedimentation quantities on the surfaces of such equipment are necessary. Outdoor testing is usually straightforward but it takes a long time to experience various environmental parameters, such as dust-laden air, wind speed, wind direction, and so on. Indoor tests, performed in a dust test chamber, are instruments for controlling various environmental parameters independently. The conventional design for a dust test chamber is aimed at providing for a test under extreme environmental conditions. The uniformity of dust sedimentation rate within the chamber is not rigorously controlled. Nevertheless, some applications such as the effect of dust sedimentation on the glazing of solar collector require uniform distribution of dustfall in the test chamber for the indoor (laboratory) test. An improved design for a conventional dust test chamber is proposed. Performance tests done with the remodeled dust test chamber based on the improved design show that the normalized standard deviation of the dustfall concentration can be controlled within 2.41% ± 1.29%. 相似文献
50.
Shiou-Huei Chen Wen-Shyong Kuo Ruey-Bin Yang 《International Journal of Applied Ceramic Technology》2019,16(5):2065-2072
In this study, carbon nanotube papers were employed in fabricating thin and broadband radar absorbing structures (RAS). Different concentrations of the CNT papers have been made by using a vacuum filtration method, with 20 × 20 cm in size and 21-27 μm in thickness. An epoxy resin was added into the CNT paper and then cured to become a composite with 1-5 wt.% of CNTs and 83-309 μm in thickness. The complex permittivity and permeability (ε′, ε″, μ′, μ″) of the CNT paper composites were measured using the transmission/reflection method in the frequency range of 2-18 GHz. The results reveal that the real (ε′) and imaginary (ε″) parts of the complex permittivity are increased with the CNT concentration. The ε′ of 5 wt.% CNT sample reaches 323 at 2 GHz and then decreases to 49.0 at 18 GHz. The ε″ reaches 321 at 2 GHz and decreases to 26.0 at 18 GHz. The CNT paper composite combined with a glass fabric composite used for a dielectric spacer is fabricated for an innovative RAS and the reflection loss is measured using the arch method in a microwave anechoic chamber. The results show that the 5 wt.% CNT paper composite/glass fabric composite absorbers attain maximum reflection loss of −13.3 dB at 12.0 GHz, −13.8 dB at 10.0 GHz, and −16.0 dB at 7.5 GHz for spacer thickness of 1.5, 2.0, and 3.0 mm, respectively. 相似文献