全文获取类型
收费全文 | 516篇 |
免费 | 24篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 111篇 |
金属工艺 | 6篇 |
机械仪表 | 10篇 |
建筑科学 | 36篇 |
矿业工程 | 2篇 |
能源动力 | 41篇 |
轻工业 | 63篇 |
水利工程 | 4篇 |
无线电 | 31篇 |
一般工业技术 | 97篇 |
冶金工业 | 51篇 |
原子能技术 | 3篇 |
自动化技术 | 82篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 10篇 |
2020年 | 4篇 |
2019年 | 7篇 |
2018年 | 11篇 |
2017年 | 14篇 |
2016年 | 12篇 |
2015年 | 11篇 |
2014年 | 16篇 |
2013年 | 30篇 |
2012年 | 22篇 |
2011年 | 30篇 |
2010年 | 15篇 |
2009年 | 19篇 |
2008年 | 24篇 |
2007年 | 24篇 |
2006年 | 23篇 |
2005年 | 25篇 |
2004年 | 8篇 |
2003年 | 16篇 |
2002年 | 14篇 |
2001年 | 4篇 |
2000年 | 7篇 |
1999年 | 14篇 |
1998年 | 18篇 |
1997年 | 15篇 |
1996年 | 6篇 |
1995年 | 9篇 |
1994年 | 6篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 8篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1972年 | 6篇 |
1963年 | 2篇 |
1951年 | 2篇 |
排序方式: 共有540条查询结果,搜索用时 15 毫秒
1.
Ochratoxin A is a mycotoxin that may cause damage to the kidneys and the immune system in man. Foods are examined for this contaminant by the laboratories responsible for official food control. At present, there are no specific provisions for the sampling and examination of ochratoxin A in foods. Therefore, recourse is made to the provisions for aflatoxins. They prescribe the processing of samples with a weight of up to 30 kg. The examination of raw coffee for ochratoxin A in conjunction with the German Food Monitoring Programme of 2000 was undertaken with various sample weights (5, 10 and 30 kg) in order to identify the influence of the sample weight on the result. Overall, the sample weight did not have an effect on the detection and level of the ochratoxin A content in the samples of raw coffee examined. 相似文献
2.
3.
4.
Bruno Gabel Denis Thiéry Vaclav Suchy Frédéric Marion-Poll Peter Hradsky Pavel Farkas 《Journal of chemical ecology》1992,18(5):693-701
The European grapevine moth (EGVM),Lobesia botrana, is a major pest of grapes in Europe. Females are attracted to a nonhost plant: tansy (Tanacetum vulgare L.), which is a common weed in Slovakian vineyards. A steam distillate extract of tansy flowers was analyzed by means of a GC-EAG technique to screen constituents detected by the olfactory receptors of EGVM females. From more than 200 GC peaks, nine peaks corresponding to monoterpenoids released an EAG response in more than 70% of the females (N=15):p-cymene,d-limonene,-thujene,-thujone,-thujone, thujyl alcohol, terpinene-4-ol, (Z)-verbenol, and piperitone. The steam distillate of tansy as well as a synthetic blend of identified compounds released consistent attraction in a field cage. The use of nonhost plants and host plant odors in integrated pest management is discussed. 相似文献
5.
6.
7.
Alisher Mirzabaev Dawit Guta Jann Goedecke Varun Gaur Jan Börner Detlef Virchow 《国际水》2015,40(5-6):772-790
This article provides a review of trade-offs and synergies of bioenergy within the water–energy–food security nexus, with emphasis on developing countries. It explores the links of bioenergy with food security, poverty reduction, environmental sustainability, health, and gender equity. It concludes that applying the nexus perspective to analyses of bioenergy widens the scope for achieving multiple-win outcomes along the above aspects. 相似文献
8.
9.
Multifunctional Gadolinium‐Doped Mesoporous TiO2 Nanobeads: Photoluminescence,Enhanced Spin Relaxation,and Reactive Oxygen Species Photogeneration,Beneficial for Cancer Diagnosis and Treatment
下载免费PDF全文
![点击此处可从《Small (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Roghayeh Imani Ralf Dillert Detlef W. Bahnemann Meysam Pazoki Tomaž Apih Veno Kononenko Neža Repar Veronika Kralj‐Iglič Gerrit Boschloo Damjana Drobne Tomas Edvinsson Aleš Iglič 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(20)
Materials with controllable multifunctional abilities for optical imaging (OI) and magnetic resonant imaging (MRI) that also can be used in photodynamic therapy are very interesting for future applications. Mesoporous TiO2 sub‐micrometer particles are doped with gadolinium to improve photoluminescence functionality and spin relaxation for MRI, with the added benefit of enhanced generation of reactive oxygen species (ROS). The Gd‐doped TiO2 exhibits red emission at 637 nm that is beneficial for OI and significantly improves MRI relaxation times, with a beneficial decrease in spin–lattice and spin–spin relaxation times. Density functional theory calculations show that Gd3+ ions introduce impurity energy levels inside the bandgap of anatase TiO2, and also create dipoles that are beneficial for charge separation and decreased electron–hole recombination in the doped lattice. The Gd‐doped TiO2 nanobeads (NBs) show enhanced ability for ROS monitored via ?OH radical photogeneration, in comparison with undoped TiO2 nanobeads and TiO2 P25, for Gd‐doping up to 10%. Cellular internalization and biocompatibility of TiO2@x Gd NBs are tested in vitro on MG‐63 human osteosarcoma cells, showing full biocompatibility. After photoactivation of the particles, anticancer trace by means of ROS photogeneration is observed just after 3 min irradiation. 相似文献
10.
Peele AG Nugent KA Rode AV Gabel K Richardson MC Strack R Siegmund W 《Applied optics》1996,35(22):4420-4425
We report an experimental investigation and comparison with simulation of the x-ray focusing of a flat, square profile microchannel plate. We use x rays with an energy of ~1.5 keV from a laser-produced plasma. The images were recorded with x-ray film. We find the focal structure to be consistent with theoretical expectations. The angular resolution of the focus is 0.96 mrad, which is a major improvement over previous results. The measured peak intensity gain is 27 ± 4, which is ~33% of that for a perfect optic. 相似文献