全文获取类型
收费全文 | 184篇 |
免费 | 0篇 |
国内免费 | 15篇 |
专业分类
综合类 | 3篇 |
化学工业 | 69篇 |
金属工艺 | 11篇 |
机械仪表 | 13篇 |
建筑科学 | 5篇 |
能源动力 | 8篇 |
轻工业 | 3篇 |
无线电 | 10篇 |
一般工业技术 | 47篇 |
冶金工业 | 1篇 |
自动化技术 | 29篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 7篇 |
2021年 | 14篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 4篇 |
2017年 | 7篇 |
2016年 | 6篇 |
2015年 | 4篇 |
2014年 | 6篇 |
2013年 | 10篇 |
2012年 | 12篇 |
2011年 | 14篇 |
2010年 | 10篇 |
2009年 | 22篇 |
2008年 | 14篇 |
2007年 | 11篇 |
2006年 | 7篇 |
2005年 | 9篇 |
2004年 | 7篇 |
2003年 | 2篇 |
2002年 | 6篇 |
2000年 | 1篇 |
1998年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
排序方式: 共有199条查询结果,搜索用时 15 毫秒
1.
《International Journal of Hydrogen Energy》2021,46(56):28397-28405
Water electrolysis powered by renewable electricity will likely be critical to a future hydrogen economy. However, the typical use of strongly acidic or alkaline electrolytes necessitates the use of expensive materials, while bubbles add to capital and operational costs, due to blocking of the electrode surface and the necessary use of pumps and gas-liquid separators. Here ‘bubble-free’ oxygen evolution at mild pH is carried out using an electrocatalyst that mimics photosystem II (PSII). The bubble-free electrode includes a gas-extracting Gore-Tex® membrane. Edge-functionalised graphene (EFG) is included to mimic the metal-binding local protein environment, and the tyrosine residue, in the oxygen evolving complex (OEC) of PSII, while MnOx and Ca2+ are incorporated to mimic the Mn4CaO5 cluster. Interaction between EFG, MnOx, and Ca2+ results in a significant, 130 mV fall in the overpotential required to drive electrocatalytic oxygen evolution at 10 mA cm−2, compared to the electrode without these biomimetic components. 相似文献
2.
Biomimetic synthesis of spherical nano-hydroxyapatite in the presence of polyethylene glycol 总被引:1,自引:0,他引:1
Spherical nano-hydroxyapatite (nano-HA) was synthesized successfully by a biomimetic method using Ca(NO3)2·4H2O and (NH4)3PO4·3H2O as reagents in the presence of polyethylene glycol (PEG). The crystalline phase, microstructure, chemical composition, and morphology of the obtained samples were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The results show that spherical nano-HA with diameter of 30–50 nm can be synthesized in the presence of a certain concentration (2–6%) of PEG. The crystallinity of HA powder synthesized in the presence of PEG was higher than that synthesized in the absence of PEG, but the crystallinity of HA reduced with increasing the concentration of PEG. The electrical conductivity (EC) of the solution revealed that PEG reduced the transfer rate of Ca2+ in the process of HA crystallization, indicating the interaction between PEG and HA. The possible mechanism of formation spherical nano-HA was discussed. 相似文献
3.
4.
Shigeo Asai Kunihito Koumoto Yushu Matsushita Eiji Yashima Masahiko Morinaga Kunihiko Takeda 《Science and Technology of Advanced Materials》2013,14(5):421-433
The center of excellence (COE) titled ‘The Creation of Nature-Guided Materials Processing’ has been established in Nagoya University as the 21st Century COE Program supported by Ministry of Education, Culture, Sports, Science and Technology. In the Nature COE, various activities on the education and research are being performed through learning the laws of nature, namely, methods of attaining ‘appearance of the maximum function under the minimum substance and energy consumption’, which the nature and living organisms have acquired through their evolution in long period. Together with such educational programs for PhD students as research incentive, oversea training, and external evaluation programs, an ‘Open-Cluster Program’ was originated for promoting researches proposed by research groups consisting of young researchers in and out of the university and also for fostering them.The researches are being advanced on materials used for living bodies, mimicking structures which nature or living bodies are forming, and producing materials by mimicking processes to form the structures observed in the nature or the living bodies. In this COE, these researches are conducted by four groups to extend the processes observed in the natural world to a new type of processing, that is, thoroughly examined and rationalized by plunging a scalpel of engineering and to establish a new academic field of materials science and engineering. 相似文献
5.
6.
Healing-on-demand materials exhibit the capability to close cracks and heal the closed/narrowed cracks when needed and to recover functionality using intrinsic or extrinsic resources. In this paper, advances in healing-on-demand polymers and polymer composites in the past decade are reviewed, covering different schemes and technologies used to trigger crack closure and to heal molecularly. A balanced review on non-load-bearing polymers and polymer composites as well as load-carrying polymers and polymer composites is presented. The progress in self-healing polymers and polymer composites has been well discussed recently in the literatures. In this review, therefore, less attention has been paid on what has been widely reported; we primarily focus on healing-on-demand materials concerned with large volume damage healing by a close-then-heal (CTH) strategy. The healing-on-demand material by the CTH approach undergoes a process of crack closure, followed by crack healing with healing agents. Healing theories, including those within the continuum damage mechanics framework, and healing efficiency evaluations are also reviewed. Perspectives on future development in this emerging research area are discussed. 相似文献
7.
气动肌肉驱动仿生关节的理论分析 总被引:1,自引:0,他引:1
根据气动肌肉的简化模型,通过引入关节的刚度和力矩-压力系数等概念,建立了由一对对抗性气动肌肉驱动仿生关节的理论模型.研究了关节的刚度和位置独立控制时对气动肌肉输入压力的要求,并对气动肌肉驱动关节运动时的几种压力变化方式进行了分析.研究表明,两个气动肌肉的压力的不同变化方式对于关节动态的刚度、转矩有很大的影响. 相似文献
8.
A carbonation route for the synthesis of hydrophobic calcium carbonate was studied. In the process, dodecanoic acid was used as an organic substrate to induce the nucleation and growth of calcium carbonate. The calcium carbonate particles were produced by means of carbonation of the mixture of calcium hydroxide and dodecanoic acid by bubbling CO2/N2 gas mixture. The operating parameters such as temperature and the concentration of the organic substrate were varied to study their influences on the active ratio and contact angle of calcium carbonate particles. The morphology of the calcium carbonate particles was characterized with scanning electron microscopy (SEM). The synthesized calcium carbonate particles in the presence of the organic substrate are rod-like and ellipse-like particles. The polymorphs were characterized with X-ray diffraction (XRD). 相似文献
9.
The biomimetic deposition of an apatite coating on polyphosphazene was investigated. A polyphosphazene having carboxylatophenoxy side groups was synthesized as a candidate polymer with heterogeneous nucleation sites for apatite deposition. Poly[bis(carboxylatophenoxy)phosphazene] (PCPP) was synthesized by a two-step synthetic route involving the synthesis of poly(dichlorophosphazene) (PDP) followed by nucleophilic replacement of the chlorine atoms of PDP with carboxylatophenoxy groups. The surface of the carboxylated polyphosphazene induced the formation of a dense layer of apatite on the surface after incubation in simulated body fluid at 37 °C with an ionic concentration approximately the same as that of human blood plasma. The results suggested an early precipitation of octacalcium phosphate and calcium phosphate intermediates on the surface, both of which are known to promote osteoblast differentiation and proliferation. 相似文献
10.