全文获取类型
收费全文 | 986篇 |
免费 | 35篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 25篇 |
综合类 | 3篇 |
化学工业 | 261篇 |
金属工艺 | 47篇 |
机械仪表 | 34篇 |
建筑科学 | 24篇 |
矿业工程 | 4篇 |
能源动力 | 66篇 |
轻工业 | 86篇 |
水利工程 | 3篇 |
石油天然气 | 6篇 |
无线电 | 65篇 |
一般工业技术 | 168篇 |
冶金工业 | 69篇 |
原子能技术 | 4篇 |
自动化技术 | 159篇 |
出版年
2024年 | 2篇 |
2023年 | 10篇 |
2022年 | 17篇 |
2021年 | 34篇 |
2020年 | 23篇 |
2019年 | 36篇 |
2018年 | 32篇 |
2017年 | 36篇 |
2016年 | 32篇 |
2015年 | 20篇 |
2014年 | 44篇 |
2013年 | 82篇 |
2012年 | 57篇 |
2011年 | 68篇 |
2010年 | 60篇 |
2009年 | 65篇 |
2008年 | 56篇 |
2007年 | 47篇 |
2006年 | 45篇 |
2005年 | 29篇 |
2004年 | 36篇 |
2003年 | 25篇 |
2002年 | 22篇 |
2001年 | 13篇 |
2000年 | 8篇 |
1999年 | 9篇 |
1998年 | 22篇 |
1997年 | 9篇 |
1996年 | 14篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1992年 | 11篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1971年 | 1篇 |
排序方式: 共有1024条查询结果,搜索用时 31 毫秒
1.
Güzin Kaban Selen Sallan Kübra Çinar Topçu Bilge Sayın Börekçi Mükerrem Kaya 《International Journal of Food Science & Technology》2022,57(7):4392-4399
The study aims to evaluate the technological properties of autochthonous strains (Lactobacillus sakei S15, Lactobacillus plantarum S24, L. plantarum S91, Pediococcus pentosaceus S128b and Staphylococcus carnosus G109) in Turkish dry fermented sausage (sucuk). After 24 h of fermentaPtion, all lactic acid bacteria strains reduced the pH to below 5.0, while the pH in the control group was above 5.3. The number of lactic acid bacteria strains reached 108–109 cfu g−1 during fermentation. Staphylococcus carnosus G109 remained at the inoculation level of 106 cfu g−1 during ripening. Lactobacillus sakei S15 as mono-culture showed higher TBARS values compared to other strains. The control group had the lowest L* value and autochthonous strains caused no significant difference for a* value. According to principal component analysis results, most volatile compounds were positively correlated with the group containing only L. sakei S15. 相似文献
2.
Ozdemir Erdem Tevfik Kartal Ugur Dikici Tuncay Erol Mustafa Yurddaskal Metin 《Journal of Materials Science: Materials in Electronics》2021,32(23):27398-27408
Journal of Materials Science: Materials in Electronics - In this study, zinc oxide (ZnO) nanowires (NWs) were successfully produced on Zn plates through electrochemical anodization in potassium... 相似文献
3.
4.
Multimedia Tools and Applications - Hotel recommendation is one of the most used application areas in recommendation systems. So far, many hotel recommendation systems have been proposed. Most of... 相似文献
5.
6.
7.
I. Isil Gurten Inal Murat Akdemir Mustafa Kaya 《International Journal of Hydrogen Energy》2021,46(41):21534-21541
In the present study, a Mn-supported catalyst material developed from Microcystis aeruginosa microalgae for hydrogen generation was tested as a supercapacitor electrode material for the first time. The catalyst material (MA-HCl-Mn) was examined for hydrogen generation through methanolysis of NaBH4, and it demonstrated good catalytic activity. Symmetric and asymmetric supercapacitor cells were prepared using MA-HCl-Mn as the electrode material. The electrochemical performance of the cells were evaluated by a two-electrode system using 2 M KOH as the electrolyte. The gravimetric capacitance of the symmetric and asymmetric cells found to be 40 F/g and 71 F/g, respectively. It was concluded that MA-HCl-Mn served as a sustainable, dual functional material showing a high catalytic activity for the hydrogen generation and a promising electrochemical performance as the supercapacitor electrode. 相似文献
8.
ABSTRACTWind turbine control is an important task to make the electricity generation secure in terms of energy demand and machine safety. It also yields to control the desired power level and optimized energy because of the assignment of turbine speed. The contactless piezoelectric wind energy harvester (CPWEH) used in this study has three piezoelectric layers located around the shaft with 120 degrees apart and they are buckled by the magnetic force without any physical contact. The superiority of this device is to generate energy for low wind speeds such as 1.5 m/s. However, for high speeds, high total harmonic distortions (THDs) govern the waveforms, thus controlling the turbine speed becomes necessary for optimizing the output power. Encouraged by this, a small low inertia dc generator is coupled with the wind turbine, and the generator terminals are connected to a resistor through a power switch to generate a braking torque that opposes to wind speed direction. By controlling the switch properly, turbine speed is ensured to remain within a certain band, which accordingly prevents the turbine from rotating very fast at damaging wind speeds. Several experiments are performed on the developed CPWEH with/without the presented control scheme which prove the existence of promising performance of our proposal. 相似文献
9.
A new series of poly(azomethine-imide)s having siloxane moities in backbone was prepared using different dianhydrides.Thermal, optical, and morphological properties of these polymers were clarified. Also, bulky CO and CF3 group effects and meta or para-substituted aldeyhde effects on the mentioned properties were evaluated. The structural characterization of poly(azomethine-imide)s was carried out using a FT-IR spectroscopy. The optical properties of the polymers were performed via an UV–Vis spectrophotometer. Optical band gap of the poly(imide)s containing azomethine was calculated between 2.20 and 2.33 eV. Thermal behavior of poly(azomethine-imide)s was also studied using TG-DTA, DSC, and DMA techniques. The onset degradation temperature and percentage char values of the polyimides were found in the range from 429 to 545 °C and 22 to 35%, respectively. Thermal stability results demonstrated that benzophenone bearing poly(azomethine-imide)s have higher onset temperature, percentage char, and the glass transition temperature than poly(azomethine-imide)s derived from hexafluoroisopropylidene. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48364. 相似文献
10.