全文获取类型
收费全文 | 105541篇 |
免费 | 8303篇 |
国内免费 | 3005篇 |
专业分类
电工技术 | 4171篇 |
技术理论 | 10篇 |
综合类 | 4551篇 |
化学工业 | 19867篇 |
金属工艺 | 4255篇 |
机械仪表 | 4616篇 |
建筑科学 | 6563篇 |
矿业工程 | 1885篇 |
能源动力 | 2842篇 |
轻工业 | 12292篇 |
水利工程 | 1681篇 |
石油天然气 | 3824篇 |
武器工业 | 527篇 |
无线电 | 9862篇 |
一般工业技术 | 14476篇 |
冶金工业 | 10196篇 |
原子能技术 | 866篇 |
自动化技术 | 14365篇 |
出版年
2024年 | 395篇 |
2023年 | 1519篇 |
2022年 | 2802篇 |
2021年 | 4013篇 |
2020年 | 3090篇 |
2019年 | 2725篇 |
2018年 | 3642篇 |
2017年 | 3634篇 |
2016年 | 3651篇 |
2015年 | 3835篇 |
2014年 | 4834篇 |
2013年 | 6788篇 |
2012年 | 6630篇 |
2011年 | 7000篇 |
2010年 | 5692篇 |
2009年 | 5350篇 |
2008年 | 5306篇 |
2007年 | 4931篇 |
2006年 | 4363篇 |
2005年 | 3743篇 |
2004年 | 2934篇 |
2003年 | 2630篇 |
2002年 | 2397篇 |
2001年 | 2041篇 |
2000年 | 2125篇 |
1999年 | 2489篇 |
1998年 | 4127篇 |
1997年 | 2923篇 |
1996年 | 2359篇 |
1995年 | 1697篇 |
1994年 | 1431篇 |
1993年 | 1141篇 |
1992年 | 682篇 |
1991年 | 529篇 |
1990年 | 451篇 |
1989年 | 414篇 |
1988年 | 349篇 |
1987年 | 267篇 |
1986年 | 212篇 |
1985年 | 193篇 |
1984年 | 154篇 |
1983年 | 110篇 |
1982年 | 127篇 |
1981年 | 136篇 |
1980年 | 129篇 |
1979年 | 57篇 |
1978年 | 57篇 |
1977年 | 152篇 |
1976年 | 278篇 |
1973年 | 65篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Wenlong Song Shoujun Wang Yang Lu Xuan Zhang Zixiang Xia Kai Sun Guangming Xin 《Ceramics International》2021,47(9):12631-12640
To enhance the tribological performance of Si3N4/TiC ceramics, MoS2/PTFE composite coatings were deposited on the ceramic substrate through spraying method. The micrographs and basic properties of the MoS2/PTFE coated samples were investigated. Dry sliding friction experiments against WC/Co ball were performed with the coated ceramics and traditional ones. These results showed that the composite coatings could significantly reduce the friction coefficient of ceramics, and protect the substrate from adhesion wear. The primary tribological mechanisms of the coated ceramics were abrasive wear, coating spalling and delamination, and the tribological property was transited from slight wear to serious wear with the increase of load because of the lower surface hardness and shear strength. The possible mechanisms for the effects of MoS2/PTFE composite coatings on the friction performance of ceramics were discussed. 相似文献
12.
Lucas Portela Oliveira Camila Cristina de Foggi Bruna Natália Alves da Silva Pimentel Marcelo Assis Juan Andrés Elson Longo Carlos Eduardo Vergani 《Ceramics International》2021,47(16):22604-22614
The present study reports for the first time the performance of silver phosphate (Ag3PO4) microcrystals as photocatalyst (degradation of Rodamine B-RhB) and antifungal agent (against Candida albicans–C. albicans) under visible-light irradiation (455 nm). Ag3PO4 microcrystals were synthesized by a simple co-precipitation (CP) method at room temperature. The structural and electronic properties of the as-synthetized Ag3PO4 have been investigated before and after 4 cycles of RhB degradation under visible light using X-ray diffraction (XRD), micro-Raman spectroscopy, UV–Vis spectrophotometer and field emission scanning electron microscopy (FE-SEM) images. The antifungal activity was analyzed in planktonic cells and 48h-biofilm of C. albicans by colony forming units (CFU) counting, confocal laser and FE-SE microscopies. Statistical analysis was carried out using SPSS software. Morphological and structural modifications of Ag3PO4 were observed upon recycling. After 4 recycles, the material maintained its photodegradation property; an eightfold increase in the efficiency of Ag3PO4 was observed in planktonic cells and a two fold increase in biofilm when irradiated under visible light. Thus, higher antifungal effectiveness against C. albicans was obtained when associated with visible-light irradiation. 相似文献
13.
15.
Romero-Garcés A. Salles De Freitas R. Marfil R. Vicente-Chicote C. Martínez J. Inglés-Romero J. F. Bandera A. 《Multimedia Tools and Applications》2022,81(3):3603-3628
Multimedia Tools and Applications - The design of robots capable of operating autonomously in changing and unstructured environments, requires using complex software architectures in which,... 相似文献
16.
Alawiya Reslan Juliano G. Haddad Liadrine Moukendza Koundi Philippe Desprs Jean-Loup Bascands Gilles Gadea 《International journal of molecular sciences》2021,22(5)
Mosquito-borne Zika virus (ZIKV) became a real threat to human health due to the lack of vaccine and effective antiviral treatment. The virus has recently been responsible for a global outbreak leading to millions of infected cases. ZIKV complications were highlighted in adults with Guillain–Barré syndrome and in newborns with increasing numbers of congenital disorders ranging from mild developmental delays to fatal conditions. The ability of ZIKV to establish a long-term infection in diverse organs including the kidneys has been recently documented but the consequences of such a viral infection are still debated. Our study aimed to determine whether the efficiency of ZIKV growth in kidney cells relates to glucose concentration. Human kidney HK-2 cells were infected with different ZIKV strains in presence of normal and high glucose concentrations. Virological assays showed a decrease in viral replication without modifying entry steps (viral binding, internalization, fusion) under high glucose conditions. This decrease replication was associated with a lower virus progeny and increased cell viability when compared to ZIKV-infected HK-2 cells in normal glucose concentration. In conclusion, we showed for the first time that an elevated glucose level influences ZIKV replication level with an effect on kidney cell survival. 相似文献
17.
Vanessa Modelski Schatkoski Thaís Larissa do Amaral Montanheiro Beatriz Rossi Canuto de Menezes Raissa Monteiro Pereira Karla Faquine Rodrigues Renata Guimarães Ribas Diego Morais da Silva Gilmar Patrocínio Thim 《Ceramics International》2021,47(3):2999-3012
Studies related to biomaterials that stimulate the repair of living tissue have increased considerably, improving the quality of many people's lives that require surgery due to traumatic accidents, bone diseases, bone defects, and reconstructions. Among these biomaterials, bioceramics and bioactive glasses (BGs) have proved to be suitable for coating materials, cement, scaffolds, and nanoparticles, once they present good biocompatibility and degradability, able to generate osteoconduction on the surrounding tissue. However, the role of biomaterials in hard tissue engineering is not restricted to a structural replacement or for guiding tissue regeneration. Nowadays, it is expected that biomaterials develop a multifunctional role when implanted, orchestrating the process of tissue regeneration and providing to the body the capacity to heal itself. In this way, the incorporation of specific metal ions in bioceramics and BGs structure, including magnesium, silver, strontium, lithium, copper, iron, zinc, cobalt, and manganese are currently receiving enhanced interest as biomaterials for biomedical applications. When an ion is incorporated into the bioceramic structure, a new category of material is created, which has several unique properties that overcome the disadvantages of primitive material and favors its use in different biomedical applications. The doping can enhance handling properties, angiogenic and osteogenic performance, and antimicrobial activity. Therefore, this review aims to summarize the effect of selected metal ion dopants into bioceramics and silicate-based BGs in bone tissue engineering. Furthermore, new applications for doped bioceramics and BGs are highlighted, including cancer treatment and drug delivery. 相似文献
18.
Liang Yan-Jun Lu You-Jun Gao De-Xin Wang Zhong-Sheng 《International Journal of Control, Automation and Systems》2022,20(2):507-514
International Journal of Control, Automation and Systems - The vibration control problem of offshore jacket platforms is studied. The model of offshore platforms with nonlinear interactions of the... 相似文献
19.
20.