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101.
Blockchain possesses the potential of transforming global supply chain management. Gartner predicts that blockchain could be able to track $2?T of goods and services in their movement across the globe by 2023, and blockchain will be a more than $3 trillion business by 2030. Nowadays, a growing number of blockchain initiatives are disrupting traditional business models in each sector. In this paper, we provide a timely and holistic overview of the state-of-the-art, challenges, gaps and opportunities in global supply chain and trade operations for both the private sector and governmental agencies, by synthesising a wide range of resources from business leaders, global international organisations, leading supply chain consulting firms, research articles, trade magazines and conferences. We then identify collaborative schema and future research directions for industry, government, and academia to jointly work together in ensuring that the full potential of blockchain is unleashed amidst the socioeconomic, geopolitical and technological disruptions that global supply chains and trade are facing. 相似文献
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Yong Xu Yun Li Songlin Li Francis Balestra Gerard Ghibaudo Wenwu Li Yen‐Fu Lin Huabin Sun Jing Wan Xinran Wang Yufeng Guo Yi Shi Yong‐Young Noh 《Advanced functional materials》2020,30(20)
Unreliable mobility values, and particularly greatly overestimated values and severely distorted temperature dependences, have recently hampered the development of the organic transistor field. Given that organic field‐effect transistors (OFETs) have been routinely used to evaluate mobility, precise parameter extraction using the electrical properties of OFETs is thus of primary importance. This review examines the origins of the various mobilities that must be determined for OFET applications, the relevant extraction methods, and the data selection limitations, which help in avoiding conceptual errors during mobility extraction. For increased precision, the review also discusses device fabrication considerations, calibration of both the specific gate‐dielectric capacitance and the threshold voltage, the contact effects, and the bias and temperature dependences, which must actually be handled with great care but have mostly been overlooked to date. This review serves as a systematic overview of the OFET mobility extraction process to ensure high precision and will also aid in improving future research. 相似文献
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为了优化高碳马氏体不锈钢8Cr13MoV的球化热处理工艺,提高其退火后的冷加工性能,采用微观组织分析法以及拉伸力学分析法研究了球化退火过程中奥氏体化保温时间和冷却速率对8Cr13MoV钢的球化效果影响。结果表明, 随着奥氏体保温时间的增加,组织中细颗粒状碳化物数量减少,索氏体数量增多,试样硬度先降低后升高,但断后伸长率持续增加;随冷却速率增加,试样组织中细颗粒状碳化物和索氏体数量、硬度和强度增加,断后伸长率降低。综合对比,奥氏体保温时间ϕ90 min时试样综合力学性能较好,冷却速率应控制在25 ℃·h-1以内。与奥氏体保温时间相比,冷却速率对力学性能的影响更加显著。 相似文献
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Akif Soltan Matthew S. Dargusch Zhiming Shi Darren Gerrard Sulaiman Al Shabibi Yu-Chieh Kuo Andrej Atrens 《工业材料与腐蚀》2020,71(6):956-979
This study studied corrosion in 0.1 M Na2SO4, 0.1 M NaCl, and 0.6 M NaCl, all saturated with Mg(OH)2, using weight loss, hydrogen evolution, and electrochemical measurements. Corrosion was similar in all cases. Nevertheless, the corrosion rates were alloy-dependent, were somewhat lower in 0.1 M Na2SO4 than in 0.1 M NaCl, and increased with NaCl concentration. The corrosion damage morphology was similar for all solutions; the extent correlated with the corrosion rate. The corrosion rates evaluated by the electrochemical methods were lower than those evaluated from hydrogen evolution, consistent with the Mg corrosion mechanism involving the unipositive Mg+ ion. 相似文献
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Gang Zhao Le Shi Jianbo Xu Xiaohui Yan T.S. Zhao 《International Journal of Hydrogen Energy》2018,43(3):1470-1478
In this paper, we have investigated the role of phosphorus (P) in nitrogen (N) and phosphorus dual-doped carbon electrocatalyst for oxygen reduction reaction (ORR) in alkaline media with three samples prepared by varying the doping orders of N and P. Results show that the resultant N-POMC (first doped with P, then N) exhibits an outstanding activity for ORR in alkaline media. The mechanism leading to the improved activity is found to be associated with the orientation effect of the first doped P on the later doped N, by increasing the ratio of graphitic-N significantly. Furthermore, a portion of the first doped P can act as the doping sites and be replaced by the later doped N, called ‘self-sacrifice’ mode, which is confirmed by both experiments and density functional theory (DFT) calculations. However, this orientation effect cannot be observed in the other two dual-doped samples. In addition, experimental and DFT calculation also prove that the amount of graphitic-N is important in improving the activity for ORR. The doping strategy reported in this work is applicable to various co-doping systems in exploring the synergy effect of different dopants and improving activity for ORR. 相似文献