全文获取类型
收费全文 | 152016篇 |
免费 | 14799篇 |
国内免费 | 8228篇 |
专业分类
电工技术 | 11117篇 |
技术理论 | 6篇 |
综合类 | 10902篇 |
化学工业 | 22533篇 |
金属工艺 | 8545篇 |
机械仪表 | 9489篇 |
建筑科学 | 11948篇 |
矿业工程 | 4141篇 |
能源动力 | 4374篇 |
轻工业 | 11605篇 |
水利工程 | 3378篇 |
石油天然气 | 6896篇 |
武器工业 | 1645篇 |
无线电 | 19524篇 |
一般工业技术 | 17414篇 |
冶金工业 | 7205篇 |
原子能技术 | 1881篇 |
自动化技术 | 22440篇 |
出版年
2024年 | 736篇 |
2023年 | 2449篇 |
2022年 | 4897篇 |
2021年 | 6747篇 |
2020年 | 4827篇 |
2019年 | 3844篇 |
2018年 | 4304篇 |
2017年 | 5017篇 |
2016年 | 4424篇 |
2015年 | 6352篇 |
2014年 | 8009篇 |
2013年 | 9843篇 |
2012年 | 11094篇 |
2011年 | 11984篇 |
2010年 | 10583篇 |
2009年 | 10192篇 |
2008年 | 9955篇 |
2007年 | 9254篇 |
2006年 | 8788篇 |
2005年 | 7275篇 |
2004年 | 4901篇 |
2003年 | 3705篇 |
2002年 | 3640篇 |
2001年 | 3108篇 |
2000年 | 2908篇 |
1999年 | 2735篇 |
1998年 | 2298篇 |
1997年 | 1993篇 |
1996年 | 1795篇 |
1995年 | 1525篇 |
1994年 | 1156篇 |
1993年 | 953篇 |
1992年 | 776篇 |
1991年 | 564篇 |
1990年 | 471篇 |
1989年 | 358篇 |
1988年 | 306篇 |
1987年 | 217篇 |
1986年 | 186篇 |
1985年 | 153篇 |
1984年 | 111篇 |
1983年 | 84篇 |
1982年 | 80篇 |
1981年 | 73篇 |
1980年 | 67篇 |
1979年 | 39篇 |
1978年 | 36篇 |
1977年 | 33篇 |
1976年 | 56篇 |
1973年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
To improve the electrochemical properties of rare-earth–Mg–Ni-based hydrogen storage alloys, the effects of stoichiometry and Cu-substitution on the phase structure and thermodynamic properties of the ... 相似文献
65.
66.
Qiang Xia Tao Feng Xiaowei Lou Ying Wang Yangying Sun Daodong Pan Jinxuan Cao 《International Journal of Food Science & Technology》2020,55(2):669-680
As a decisive attribute, flavour could be influenced by HP treatments through multiple physical and chemical pathways within the high pressure (HP)-assisted meat curing process. This investigation aimed to identify the major pathway influencing volatile flavour patterns of two representative vinasse-cured duck (VCD) products with HP treatments (150–300 MPa/15 min), including wet and dry types, by employing headspace fingerprinting as an untargeted approach. Results suggested that HP treatments greatly lowered moisture contents and increased Warner-Bratzler shear force and thiobarbituric acid reactive substances of the cured samples. According to multivariate models, the volatile flavour patterns of the HP-processed VCD could be clearly separated from the unprocessed samples, but the VCD pressurised at different intensities represented similar volatile fingerprinting, which was validated by e-nose analysis. The discriminant analysis (OPLS-DA) model outlined vinasse-derived ethanol, acetic acid, 3-methyl-1-butanol, 2-methyl-1-butanol, phenethyl alcohol and 2-methyl-3-octanone as the major discriminant aromas across the unpressurised and pressurised samples. 相似文献
67.
The application of deep learning in the field of object detection has
experienced much progress. However, due to the domain shift problem, applying an
off-the-shelf detector to another domain leads to a significant performance drop. A
large number of ground truth labels are required when using another domain to train
models, demanding a large amount of human and financial resources. In order to avoid
excessive resource requirements and performance drop caused by domain shift, this
paper proposes a new domain adaptive approach to cross-domain vehicle detection. Our
approach improves the cross-domain vehicle detection model from image space and
feature space. We employ objectives of the generative adversarial network and cycle
consistency loss for image style transfer in image space. For feature space, we align
feature distributions between the source domain and the target domain to improve the
detection accuracy. Experiments are carried out using the method with two different
datasets, proving that this technique effectively improves the accuracy of vehicle
detection in the target domain. 相似文献
69.
Neural Machine Translation (NMT) is an end-to-end learning approach for
automated translation, overcoming the weaknesses of conventional phrase-based translation
systems. Although NMT based systems have gained their popularity in commercial
translation applications, there is still plenty of room for improvement. Being the most
popular search algorithm in NMT, beam search is vital to the translation result. However,
traditional beam search can produce duplicate or missing translation due to its target
sequence selection strategy. Aiming to alleviate this problem, this paper proposed neural
machine translation improvements based on a novel beam search evaluation function. And
we use reinforcement learning to train a translation evaluation system to select better
candidate words for generating translations. In the experiments, we conducted extensive
experiments to evaluate our methods. CASIA corpus and the 1,000,000 pairs of bilingual
corpora of NiuTrans are used in our experiments. The experiment results prove that the
proposed methods can effectively improve the English to Chinese translation quality. 相似文献
70.
随着掘进工作面自动化程度的提高,掘进巷道速度也在日益加快,而现有的顺槽皮带机机尾移动缓慢且移动时工作量大,需要两三人配合操作,存在一定的安全隐患。针对以上问题,研发可调偏迈步式胶带自移机尾,具有与悬挂二运皮带转载机搭接行程长,可以迈步式前进,自动调偏等功能,同时,可以降低工人的劳动强度,加快巷道掘进速度。 相似文献