全文获取类型
收费全文 | 38624篇 |
免费 | 14801篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 757篇 |
综合类 | 2篇 |
化学工业 | 17278篇 |
金属工艺 | 353篇 |
机械仪表 | 728篇 |
建筑科学 | 1705篇 |
矿业工程 | 4篇 |
能源动力 | 856篇 |
轻工业 | 7190篇 |
水利工程 | 295篇 |
石油天然气 | 54篇 |
无线电 | 6997篇 |
一般工业技术 | 11610篇 |
冶金工业 | 972篇 |
原子能技术 | 29篇 |
自动化技术 | 4601篇 |
出版年
2023年 | 20篇 |
2022年 | 38篇 |
2021年 | 246篇 |
2020年 | 1458篇 |
2019年 | 3206篇 |
2018年 | 3140篇 |
2017年 | 3470篇 |
2016年 | 3925篇 |
2015年 | 3976篇 |
2014年 | 3913篇 |
2013年 | 5045篇 |
2012年 | 2743篇 |
2011年 | 2384篇 |
2010年 | 2666篇 |
2009年 | 2568篇 |
2008年 | 2082篇 |
2007年 | 1954篇 |
2006年 | 1695篇 |
2005年 | 1407篇 |
2004年 | 1370篇 |
2003年 | 1324篇 |
2002年 | 1281篇 |
2001年 | 1119篇 |
2000年 | 1084篇 |
1999年 | 482篇 |
1998年 | 173篇 |
1997年 | 126篇 |
1996年 | 76篇 |
1995年 | 49篇 |
1994年 | 54篇 |
1993年 | 50篇 |
1992年 | 33篇 |
1991年 | 29篇 |
1990年 | 25篇 |
1989年 | 23篇 |
1988年 | 23篇 |
1987年 | 26篇 |
1986年 | 17篇 |
1985年 | 13篇 |
1984年 | 11篇 |
1983年 | 15篇 |
1982年 | 9篇 |
1981年 | 16篇 |
1980年 | 14篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1977年 | 8篇 |
1976年 | 14篇 |
1975年 | 4篇 |
1972年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
Bijan Nasri‐Nasrabadi Akif Kaynak Shayan Seyedin Zahra Komeily‐Nia Abbas Z Kouzani 《Polymer International》2019,68(5):922-928
Recent advances in three‐dimensional (3D) printing have enabled the fabrication of interesting structures which are not achievable using traditional fabrication approaches. The 3D printing of carbon microtube composite inks allows fabrication of conductive structures for practical applications in soft robotics and tissue engineering. However, it is challenging to achieve 3D printed structures from solution‐based composite inks, which requires an additional process to solidify the ink. Here, we introduce a wet 3D printing technique which uses a coagulation bath to fabricate carbon microtube composite structures. We show that through a facile nanogrooving approach which introduces cavitation and channels on carbon microtubes, enhanced interfacial interactions with a chitosan polymer matrix are achieved. Consequently, the mechanical properties of the 3D printed composites improve when nanogrooved carbon microtubes are used, compared to untreated microtubes. We show that by carefully controlling the coagulation bath, extrusion pressure, printing distance and printed line distance, we can 3D print composite lattices which are composed of well‐defined and separated printed lines. The conductive composite 3D structures with highly customised design presented in this work provide a suitable platform for applications ranging from soft robotics to smart tissue engineering scaffolds. © 2019 Society of Chemical Industry 相似文献
3.
Rosa Maria Vitale Fabio Arturo Iannotti Pietro Amodeo 《International journal of molecular sciences》2021,22(9)
Cannabidiol (CBD), the major nonpsychoactive Cannabis constituent, has been proposed for the treatment of a wide panel of neurological and neuropsychiatric disorders, including anxiety, schizophrenia, epilepsy and drug addiction due to the ability of its versatile scaffold to interact with diverse molecular targets that are not restricted to the endocannabinoid system. Albeit the molecular mechanisms responsible for the therapeutic effects of CBD have yet to be fully elucidated, many efforts have been devoted in the last decades to shed light on its complex pharmacological profile. In particular, an ever-increasing number of molecular targets linked to those disorders have been identified for this phytocannabinoid, along with the modulatory effects of CBD on their cascade signaling. In this view, here we will try to provide a comprehensive and up-to-date overview of the molecular basis underlying the therapeutic effects of CBD involved in the treatment of neurological and neuropsychiatric disorders. 相似文献
4.
Karolina Storesund Francine Amon Anne Steen‐Hansen Shayesteh Haghighatpanah Ida Larsson 《火与材料》2021,45(1):181-190
The aim of this exploratory study has been to investigate the fire properties and environmental aspects of different upholstery material combinations, mainly for domestic applications. An analysis of the sustainability and circularity of selected textiles, along with lifecycle assessment, is used to qualitatively evaluate materials from an environmental perspective. The cone calorimeter was the primary tool used to screen 20 different material combinations from a fire performance perspective. It was found that textile covers of conventional fibres such as wool, cotton and polyester, can be improved by blending them with fire resistant speciality fibres. A new three‐dimensional web structure has been examined as an alternative padding material, showing preliminary promising fire properties with regard to ignition time, heat release rates and smoke production. 相似文献
5.
Moustapha Moussa Amudhan Ponrajan Osvaldo H. Campanella Martin R. Okos Mario M. Martinez Bruce R. Hamaker 《International Journal of Food Science & Technology》2022,57(7):4594-4601
Traditional West African pearl millet couscous products are popular; however, their preparation is laborious, time-consuming and energy-demanding, involving agglomeration, steaming, drying and sieving steps. In this study, a process was developed to produce millet couscous using a high pressure, high temperature and low-cost single-screw extruder. The innovation was to directly process the cooked low-moisture extrudate to a couscous product by drying and milling to the appropriate particle size (ranging between 1 and 2 mm). Throughput for the traditional process as prepared for commercial sale is 50 kg per day, but with the same amount of labour, the extrusion process yields ~350 kg per day. A consumer sensory study held in Niamey (Niger) showed that the extruded millet couscous was comparable to traditional couscous, though this was dependent on selection of the proper millet variety. This novel extrusion process could stimulate small- to medium-scale manufacturing of couscous and couscous-type products in West Africa. 相似文献
6.
Fluorescence‐Activated Cell Sorters: Standing Surface Acoustic Wave (SSAW)‐Based Fluorescence‐Activated Cell Sorter (Small 40/2018) 下载免费PDF全文
7.
8.
SPEEK/cSMM membrane for simultaneous electricity generation and wastewater treatment in microbial fuel cell 下载免费PDF全文
9.
Efficacy of Crude and Purified Chitinases (SsChi50) Extracted from Offal Red Scorpion Fish in Biological Control of Chickpea Weevil (Callosobruchus maculatus L.) 下载免费PDF全文
10.
Quality enhancement of the abundant under‐valued crustacean,lobster krill (Munida spp.), during its chilled storage 下载免费PDF全文
Bibiana García‐Soto José M. Miranda Jorge Barros‐Velázquez Santiago P. Aubourg 《International Journal of Food Science & Technology》2015,50(3):708-716
Lobster krill (Munida genus) represents an under‐valued crustacean frequently caught on European fishing banks. In this work, its sensory, microbiological and biochemical qualities were evaluated during chilled storage. Additionally, the effects of a prestorage antimelanosic treatment consisting of soaking in sodium metabisulphite (SMB) solutions at two different concentrations (0.25% and 0.75%) were also studied. SMB prestorage treatment provided lobster specimens that still exhibited acceptable sensory quality after 10 days of storage, while control specimens were unacceptable at that time. SMB treatment also resulted in a significant (P < 0.05) inhibition of microbial growth, mainly of Enterobacteriaceae, psychrotrophes and proteolytic bacteria. Low lipid oxidation levels were observed for all batches; however, a significantly higher (P < 0.05) retention of polyunsaturated fatty acids was found in SMB‐treated lobster, especially in the 0.75% SMB batch. The results presented here open the way to the potential commercialisation of currently under‐utilised lobster krill as a chilled product. 相似文献