全文获取类型
收费全文 | 12257篇 |
免费 | 831篇 |
国内免费 | 462篇 |
专业分类
电工技术 | 319篇 |
技术理论 | 2篇 |
综合类 | 813篇 |
化学工业 | 1006篇 |
金属工艺 | 1354篇 |
机械仪表 | 3461篇 |
建筑科学 | 395篇 |
矿业工程 | 209篇 |
能源动力 | 169篇 |
轻工业 | 404篇 |
水利工程 | 37篇 |
石油天然气 | 153篇 |
武器工业 | 144篇 |
无线电 | 492篇 |
一般工业技术 | 2322篇 |
冶金工业 | 338篇 |
原子能技术 | 24篇 |
自动化技术 | 1908篇 |
出版年
2024年 | 65篇 |
2023年 | 368篇 |
2022年 | 406篇 |
2021年 | 638篇 |
2020年 | 544篇 |
2019年 | 421篇 |
2018年 | 339篇 |
2017年 | 422篇 |
2016年 | 360篇 |
2015年 | 340篇 |
2014年 | 558篇 |
2013年 | 1115篇 |
2012年 | 623篇 |
2011年 | 521篇 |
2010年 | 392篇 |
2009年 | 444篇 |
2008年 | 457篇 |
2007年 | 642篇 |
2006年 | 691篇 |
2005年 | 647篇 |
2004年 | 578篇 |
2003年 | 510篇 |
2002年 | 479篇 |
2001年 | 401篇 |
2000年 | 327篇 |
1999年 | 284篇 |
1998年 | 196篇 |
1997年 | 151篇 |
1996年 | 155篇 |
1995年 | 122篇 |
1994年 | 77篇 |
1993年 | 74篇 |
1992年 | 41篇 |
1991年 | 41篇 |
1990年 | 23篇 |
1989年 | 13篇 |
1988年 | 10篇 |
1987年 | 11篇 |
1986年 | 21篇 |
1985年 | 7篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1964年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
1951年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
分析了制造业对环境的影响,介绍了绿色制造的概念及内涵,研究了产品从设计、材料选择、生产、包装、使用到废弃处理整个生命周期中的绿色制造关键技术。 相似文献
92.
《Mechatronics》2016
In the European manufacturing industry, production batches are decreasing, resulting in an increase in required changeovers. Companies are pushed to respond quickly and cost-efficient to changing markets. One way for Small and Medium sized Enterprises (SMEs) to become more agile, is to incorporate industrial robots in their production processes; larger enterprises already use this versatile piece of equipment for large batch sizes. To do so, a new perspective and approach is required, tailored to dynamic manufacturing systems in which production systems and components can be easily reconfigured, altered, swapped or replaced. A modular system architecture was developed within project SInBot upon which challenges in dynamic cooperation between robots and humans were projected. The developed system uses decentralized control and distributed intelligence, linked through an extensible, flexible, and fault-tolerant communication architecture. The rapidly growing complexity of traditional systems is compared to its decentralized counterpart to illustrate some of the many advantages of this new system architecture. A manufacturing scenario analogue is discussed and the approach to verify the performance of inner-system components, as well as the benefits of this approach. Key challenges that are encountered in implementing the cooperation into the current industrial environments are identified and projected upon the verification system. 相似文献
93.
Ileana Recalde Andrés. F. Gualdrón-Reyes Carlos Echeverría-Arrondo Alexis Villanueva-Antolí Jorge Simancas Jhonatan Rodriguez-Pereira Marcileia Zanatta Iván Mora-Seró Victor Sans 《Advanced functional materials》2023,33(8):2210802
The use of non-toxic and low-cost vitamins like α-tocopherol (α-TCP, vitamin E) to improve the photophysical properties and stability of perovskite nanocrystals (PNCs), through post-synthetic ligand surface passivation, is demonstrated for the first time. Especially interesting is its effect on CsPbI3 the most unstable inorganic PNC. Adding α-TCP produces that the photoluminescence quantum yield (PLQY) of freshly prepared and aged PNCs achieves values of ≈98% and 100%, respectively. After storing 2 months under ambient air and 60% relative humidity, PLQY is maintained at 85% and 67%, respectively. α-TCP restores the PL features of aged CsPbI3 PNCs, and mediates the radiative recombination channels by reducing surface defects. In addition, the combination of α-TCP and PNCs facilitates the chemical formulation to prepare PNCs-acrylic polymer composites processable by additive manufacturing. This enables the development of complex shaped parts with improved luminescent features and long-term stability for 4 months, which is not possible for non-modified PNCs. A PLQY ≈92% is reached in the 3D printed polymer/PNC composite, the highest value obtained for a red-emitting composite solid until now as far as it is known. The passivation shell provided by α-TCP makes that PNCs inks do not suffer any degradation process avoiding the contact with the environment and preserve their properties after reacting with polar monomers during composite polymerization. 相似文献
94.
Vanessa Sanchez Kausalya Mahadevan Gabrielle Ohlson Moritz A. Graule Michelle C. Yuen Clark B. Teeple James C. Weaver James McCann Katia Bertoldi Robert J. Wood 《Advanced functional materials》2023,33(26):2212541
Soft robots adapt passively to complex environments due to their inherent compliance, allowing them to interact safely with fragile or irregular objects and traverse uneven terrain. The vast tunability and ubiquity of textiles has enabled new soft robotic capabilities, especially in the field of wearable robots, but existing textile processing techniques (e.g., cut-and-sew, thermal bonding) are limited in terms of rapid, additive, accessible, and waste-free manufacturing. While 3D knitting has the potential to address these limitations, an incomplete understanding of the impact of structure and material on knit-scale mechanical properties and macro-scale device performance has precluded the widespread adoption of knitted robots. In this work, the roles of knit structure and yarn material properties on textile mechanics spanning three regimes–unfolding, geometric rearrangement, and yarn stretching–are elucidated and shown to be tailorable across unique knit architectures and yarn materials. Based on this understanding, 3D knit soft actuators for extension, contraction, and bending are constructed. Combining these actuation primitives enables the monolithic fabrication of entire soft grippers and robots in a single-step additive manufacturing procedure suitable for a variety of applications. This approach represents a first step in seamlessly “printing” conformal, low-cost, customizable textile-based soft robots on-demand. 相似文献
95.
随着科技的快速发展,诸多技术的涌现及其应用能够明显提升实际产业项目的运作效能,从而为企业管理效能与产品质量提供优质的保障。对于塑料制造加工而言,采取自动化技术来改善生产效率及其质量是极为明智的选择。通过研究塑料制造自动化流程中的技术手段,能够更为清晰地了解机器人在塑料制造自动化中的技术应用及其实际效能,从当前实践领域当中所观察到的机器人的应用状况来分析,机器人塑料制造自动化中的应用前景较为广阔,且值得在相关制造业领域中进行推广应用。本文就机器人在塑料制造自动化中的技术应用及发展进行深入探究,以期为同类型制造企业选用机器人提供有益的借鉴。 相似文献
96.
C. R. Helms J. L. Meléndez H. G. Robinson S. Holander J. Hasan S. Halepete 《Journal of Electronic Materials》1995,24(9):1137-1142
The strategy and status of a process simulator for the flexible manufacture of HgCdTe infrared focal plane arrays is described.
It has capabilities to simulate Hg vacancy and interstitial effects and cation impurity diffusion, for various boundary conditions
in one dimension. Numerical complexity of these problems stems from the necessity of solving diffusion equations for each
defect that are coupled to each other via nonlinear interaction terms. The simulator has already led to the prediction of
heretofore unexplained experimental data. Current extensions of the one-dimensional simulator planned over the next few years
include the addition of Te antisites, antisite-Hg vacancy pairs, and In-Hg vacancy pairs, ion implantation, and various energetic
processes (such as ion milling). The sequential effect of various processes will be possible with the input to the simulator
looking much like a process run sheet. 相似文献
97.
98.
将三维实体仿真技术引进雷达制造工艺设计中,并举例加以说明,汪明了三维实体仿真技术在加工中的运用可以辅助工艺规划,使工艺方案的提出更加合理、科学、便捷。 相似文献
99.
Chaoying Zhang Jiaxing Gong Jingyu Zhang Ziyu Zhu Ying Qian Kejie Lu Siyi Zhou Tianyi Gu Huiming Wang Yong He Mengfei Yu 《Advanced functional materials》2023,33(40):2302251
Autograft replaced by a nerve guidance conduit (NGC) is challenging in peripheral nerve injury because current NGC is still limited by precise conductivity and excellent biocompatibility in vivo, which influences the peripheral nerve repair even for a long lesion gap repair. Several particular elements have the potential function for nerve conductivity acceleration based on the traditional three factors of neural tissue engineering. The review aims to address three questions: 1) What is the superior factor for nerve conduction in the application? 2) How can a more conductive regenerative scaffold be constructed in vivo? 3) What is the next step in nerve regeneration for NGC? The bibliometrics analysis of NGC-related references is adopted to acquire that the conductive material, manufacturing technology of neural scaffold, and electrical stimulation (ES) play essential roles in the acceleration of nerve conduction. This review visually analyses the research status and summarizes the main types of conductive materials, the manufacturing technologies of neural scaffolds, and the characteristics of ES. The viewpoints and outlook of developing NGC are also discussed in this review. The proposed three elements are expected to improve the nerve conduction of NGC in vivo and even address the dilemma of long-distance peripheral nerve injury. 相似文献
100.
同步送粉激光增材制造是一种通过粉末添加方式快速制造实体零件的先进技术。在激光增材制造过程中, 激光与粉末束流将产生相互作用, 激光能量的损失是由于粉末束流对激光的散射作用。本文基于米氏散射理论建立数学模型, 研究粉末束流对激光能量的散射损失规律。结果表明: 激光能量散射损失与粉末颗粒物理特性、激光波长、粉末颗粒大小、送粉量等因素有关。粉末颗粒导电性能越好, 其对激光的散射损失越大;激光波长越长, 散射损失也越大;而在相同送粉量时, 粉末颗粒半径越小, 激光能量散射损失越大。从激光能量散射损失角度考虑, 激光增材制造宜选择短波长激光和大颗粒粉末。 相似文献