全文获取类型
收费全文 | 46683篇 |
免费 | 14959篇 |
国内免费 | 28篇 |
专业分类
电工技术 | 1016篇 |
综合类 | 11篇 |
化学工业 | 18726篇 |
金属工艺 | 679篇 |
机械仪表 | 1176篇 |
建筑科学 | 1821篇 |
矿业工程 | 3篇 |
能源动力 | 1129篇 |
轻工业 | 7841篇 |
水利工程 | 314篇 |
石油天然气 | 49篇 |
无线电 | 8225篇 |
一般工业技术 | 13065篇 |
冶金工业 | 2199篇 |
原子能技术 | 172篇 |
自动化技术 | 5244篇 |
出版年
2023年 | 95篇 |
2022年 | 160篇 |
2021年 | 452篇 |
2020年 | 1547篇 |
2019年 | 3281篇 |
2018年 | 3283篇 |
2017年 | 3587篇 |
2016年 | 4097篇 |
2015年 | 4116篇 |
2014年 | 4133篇 |
2013年 | 5417篇 |
2012年 | 3166篇 |
2011年 | 2906篇 |
2010年 | 2991篇 |
2009年 | 2929篇 |
2008年 | 2452篇 |
2007年 | 2196篇 |
2006年 | 1971篇 |
2005年 | 1650篇 |
2004年 | 1581篇 |
2003年 | 1537篇 |
2002年 | 1480篇 |
2001年 | 1316篇 |
2000年 | 1251篇 |
1999年 | 694篇 |
1998年 | 732篇 |
1997年 | 455篇 |
1996年 | 338篇 |
1995年 | 234篇 |
1994年 | 216篇 |
1993年 | 195篇 |
1992年 | 114篇 |
1991年 | 114篇 |
1990年 | 93篇 |
1989年 | 69篇 |
1988年 | 68篇 |
1987年 | 68篇 |
1986年 | 66篇 |
1985年 | 57篇 |
1984年 | 68篇 |
1983年 | 64篇 |
1982年 | 45篇 |
1981年 | 46篇 |
1980年 | 55篇 |
1979年 | 40篇 |
1978年 | 33篇 |
1977年 | 32篇 |
1976年 | 56篇 |
1975年 | 18篇 |
1974年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Shin Hansub Sim Sungyong Kwon Hyukyoon Hwang Sangheum Lee Younho 《International Journal of Information Security》2022,21(1):25-36
International Journal of Information Security - This paper deals with a well-known problem in the area of the smudge attacks: when a user draws a pattern to unlock the pattern lock on a smartphone... 相似文献
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.
Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 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.
Ava Kwong Cecilia Y. S. Ho Vivian Y. Shin Chun Hang Au Tsun Leung Chan Edmond S. K. Ma 《International journal of molecular sciences》2021,22(2)
The germline carrier of the BRCA1 pathogenic mutation has been well proven to confer an increased risk of breast and ovarian cancer. Despite BRCA1 biallelic pathogenic mutations being extremely rare, they have been reported to be embryonically lethal or to cause Fanconi anemia (FA). Here we describe a patient who was a 48-year-old female identified with biallelic pathogenic mutations of the BRCA1 gene, with no or very subtle FA-features. She was diagnosed with ovarian cancer and breast cancer at the ages of 43 and 44 and had a strong family history of breast and gynecological cancers. 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.
10.
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