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931.
电能路由器将在以微网为基本单元的未来能源互联网中占据核心地位,针对电能路由器采用定制化设计存在的功能单一、灵活性低下等问题,该文利用软件定义技术对电能路由器进行研究,采用数字实时仿真和模块化变流器融合技术,实现软件定义电能路由器工具化实验平台的设计搭建,并通过分析研究一个九端口电能路由器的实用案例证明了方案的有效性和可行性。所提方法为电能路由器提供了一种面向工程实施的试验新范式,使得电能路由器设计向“硬件模块化+功能软件化”模式演进,更好地推进未来电能路由器的智能化、体系化发展。
相似文献932.
Khalid A. Alissa Mohammed Maray Areej A. Malibari Sana Alazwari Hamed Alqahtani Mohamed K. Nour Marwa Obbaya Mohamed A. Shamseldin Mesfer Al Duhayyim 《计算机、材料和连续体(英文)》2023,74(3):5349-5367
Emerging technologies such as edge computing, Internet of Things (IoT), 5G networks, big data, Artificial Intelligence (AI), and Unmanned Aerial Vehicles (UAVs) empower, Industry 4.0, with a progressive production methodology that shows attention to the interaction between machine and human beings. In the literature, various authors have focused on resolving security problems in UAV communication to provide safety for vital applications. The current research article presents a Circle Search Optimization with Deep Learning Enabled Secure UAV Classification (CSODL-SUAVC) model for Industry 4.0 environment. The suggested CSODL-SUAVC methodology is aimed at accomplishing two core objectives such as secure communication via image steganography and image classification. Primarily, the proposed CSODL-SUAVC method involves the following methods such as Multi-Level Discrete Wavelet Transformation (ML-DWT), CSO-related Optimal Pixel Selection (CSO-OPS), and signcryption-based encryption. The proposed model deploys the CSO-OPS technique to select the optimal pixel points in cover images. The secret images, encrypted by signcryption technique, are embedded into cover images. Besides, the image classification process includes three components namely, Super-Resolution using Convolution Neural Network (SRCNN), Adam optimizer, and softmax classifier. The integration of the CSO-OPS algorithm and Adam optimizer helps in achieving the maximum performance upon UAV communication. The proposed CSODL-SUAVC model was experimentally validated using benchmark datasets and the outcomes were evaluated under distinct aspects. The simulation outcomes established the supreme better performance of the CSODL-SUAVC model over recent approaches. 相似文献
933.
In the Industry 4.0 era, disruptive technologies such as big data analytics, blockchain, Internet-of-Things, and additive manufacturing have become major forces driving supply chain transformation. Under such circumstances, particular attention should be attached to balancing resilience and efficiency of the supply chain, especially in the presence of more turbulence. In this study, we first summarize the conflicts between supply chain efficiency and supply chain resilience regarding practices and objectives. Then, we discuss the positive effects of disruptive technologies in improving resilience and efficiency. Afterwards, we propose a research agenda that covers both the influence mechanism and trade-off mechanism of these technologies in terms of resilience and efficiency. 相似文献
934.
真值发现是数据集成领域具有挑战性的研究热点之一。传统的方法利用数据源与观测值之间的交互关系推断真值,缺乏足够的特征信息;基于深度学习的方法可以有效地进行特征抽取,但其性能依赖于大量手工标注,而在实际应用中很难获取到大量高质量的真值标签。为克服以上问题,本文提出一种基于多特征融合的无监督真值发现方法(Unsupervised truth discovery method based on multi-feature fusion, MFOTD)。首先,利用集成学习无监督标注“真值”标签;然后,分别使用预训练模型 Bert和独热编码获取观测值的语义特征和交互特征;最后,融合观测值多种特征并使用其“真值”标签构建初始训练集,通过自训练方式训练真值预测模型。在两个真实数据集上的实验结果表明,与已有方法相比,本文所提出的方法具有更高的真值发现准确性。 相似文献
935.
采用纳秒脉冲激光对石化设备普遍使用的20钢表面锈蚀层以及油污进行了激光清洗试验,通过正交实验法得到优化后的激光清洗工艺参数,在激光功率18 W,激光脉冲重复频率75kHz,扫描速度3 000mm/s的清洗工艺参数下可有效去除20钢表面的锈蚀层;在激光功率20 W,激光脉冲重复频率75 kHz,扫描速度2 250 mm/s的清洗工艺参数下可有效去除20钢表面附着的油污。分析了激光清洗前后材料表面形貌的变化,研究了激光清洗前后表面的显微硬度以及耐腐蚀性,结果表明:激光清洗可以在不改变材料的耐腐蚀性能的同时提升材料表面的显微硬度,从而达到理想的激光清洗效果。 相似文献
936.
目的 为了应对日益恶化的全球气候变化,并实现碳中和的目标,研究低碳化技术在包装行业的应用成为当下至关重要的任务。为了推动包装行业在碳中和背景下的低碳化转型,有必要对现有的低碳化技术进行分类和梳理。方法 从碳减排和碳移除两方面对包装行业已有的低碳化技术进行了研究。综述当前可降解生物塑料和聚合物单体化学循环技术在包装中的应用,介绍了几种清洁能源以及碳捕捉、碳利用和碳储存技术的发展现状。结论 对包装行业而言,实现碳中和的目标还面临着很多挑战。包装行业在推进碳中和目标时要选取与发展适合的低碳能源和碳中和技术。 相似文献
937.
938.
Self-cleaning of tin contaminants was realized utilizing a self-driven hydrogen plasma. Cleaning rates of 0.7–6 nm min-1 were achieved for removal of discontinuous tin particles at different powers. The analysis of topography and cross-sectional morphology revealed that the removal of tin particles was achieved through top-down cleaning with hydrogen plasma, where the upper part of spherical tin particles was always more intensely cleaned under the synergistic effect of hydrogen atoms and ions due to the vertical incidence of ions to the substrate during the whole cleaning process. Redeposition of tin atoms caused by physical sputtering and its promotion of the chemical cleaning effect was observed for the first time. Reflectance recovery measurements during cleaning and surface analysis of the substrate after cleaning indicated that nondestructive cleaning with a reflectance loss of less than 1% can be achieved at a relatively low power of 120 W. Plasma-induced substrate damage, such as holes and valleys, reduced the reflectance of the substrate when cleaning was performed at a high power greater than 120 W, so this method should only be considered for application under conditions without substrate exposure. This study provides a comprehensive understanding of the removal of discontinuous tin particles using the in situ self-driven plasma cleaning method, and also provides meaningful guidance for the extension of this method in other potential fields of application. 相似文献
939.
940.
Li YANG 《等离子体科学和技术》2022,24(10):105505
Atmospheric pressure plasma jet (APPJ) was used to clean nitrogen-containing carbon films (C–N) fabricated by plasma-assisted chemical vapor deposition method employing the plasma surface interaction linear device at Sichuan University (SCU-PSI). The properties of the contaminated films on the surface of pristine and He-plasma pre-irradiated tungsten matrix, such as morphology, crystalline structure, element composition and chemical structure were characterized by scanning electron microscopy, grazing incidence x-ray diffraction and x-ray photoelectron spectroscopy. The experimental results revealed that the removal of C–N film with a thickness of tens of microns can be realized through APPJ cleaning regardless of the morphology of the substrates. Similar removal rates of 16.82 and 13.78 μm min−1 were obtained for C–N films deposited on a smooth pristine W surface and rough fuzz-covered W surface, respectively. This is a remarkable improvement in comparison to the traditional cleaning method. However, slight surface oxidation was found after APPJ cleaning, but the degree of oxidation was acceptable with an oxidation depth increase of only 3.15 nm. Optical emission spectroscopy analysis and mass spectrometry analysis showed that C–N contamination was mainly removed through chemical reaction with reactive oxygen species during APPJ treatment using air as the working gas. These results make APPJ cleaning a potentially effective method for the rapid removal of C–N films from the wall surfaces of fusion devices. 相似文献