全文获取类型
收费全文 | 314篇 |
免费 | 36篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 159篇 |
金属工艺 | 5篇 |
机械仪表 | 5篇 |
建筑科学 | 3篇 |
能源动力 | 8篇 |
轻工业 | 79篇 |
无线电 | 7篇 |
一般工业技术 | 36篇 |
冶金工业 | 28篇 |
自动化技术 | 18篇 |
出版年
2022年 | 32篇 |
2021年 | 43篇 |
2020年 | 10篇 |
2019年 | 21篇 |
2018年 | 14篇 |
2017年 | 21篇 |
2016年 | 11篇 |
2015年 | 13篇 |
2014年 | 15篇 |
2013年 | 16篇 |
2012年 | 21篇 |
2011年 | 13篇 |
2010年 | 15篇 |
2009年 | 7篇 |
2008年 | 14篇 |
2007年 | 6篇 |
2006年 | 11篇 |
2005年 | 7篇 |
2004年 | 5篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 7篇 |
1997年 | 8篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1983年 | 3篇 |
1980年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有350条查询结果,搜索用时 375 毫秒
41.
42.
Michał Terlecki Saumya Badoni Michał K. Leszczyński Stanisław Gierlotka Iwona Justyniak Hanako Okuno Małgorzata Wolska-Pietkiewicz Daniel Lee Gaël De Paëpe Janusz Lewiński 《Advanced functional materials》2021,31(49):2105318
Colloidal nanoplatelets (NPLs) and nanosheets with controlled thickness have recently emerged as an exciting new class of quantum-sized nanomaterials with substantially distinct optical properties compared to 0D quantum dots. Zn-based NPLs are an attractive heavy-metal-free alternative to the so far most widespread cadmium chalcogenide colloidal 2D semiconductor nanostructures, but their synthesis remains challenging to achieve. The authors describe herein, to the best of their knowledge, the first synthesis of highly stable ZnO NPLs with the atomically precise thickness, which for the smallest NPLs is 3.2 nm (corresponding to 12 ZnO layers). Furthermore, by means of dynamic nuclear polarization-enhanced solid-state 15N NMR, the original role of the benzamidine ligands in stabilizing the surface of these nanomaterials is revealed, which can bind to both the polar and non-polar ZnO facets, acting either as X- or L-type ligands, respectively. This bimodal stabilization allows obtaining hexagonal NPLs for which the surface energy of the facets is modulated by the presence of the ligands. Thus, in-depth study of the interactions at the organic–inorganic interfaces provides a deeper understanding of the ligand–surface interface and should facilitate the future chemistry of stable-by-design nano-objects. 相似文献
43.
The effects of the structure of di- and triblock copolymers of poly(L-lysine) – LYS with poly(ethylene glycol) – PEG as well as the length of nonionic fragment in the LYS-PEG macromolecule on the copolymer chains conformation in the adsorption layer formed on the colloidal silica (SiO2) surface were examined. Spectrophotometry and turbidimetry were applied for the determination of copolymer adsorbed amounts and stability coefficients of silica aqueous suspensions. The electrokinetic parameters such as solid surface charge density and zeta potential were also estimated. The adsorption of LYS-PEG was proved to be the highest at pH 10 whereas the lowest adsorption on the solid surface was found for the triblock copolymer with long fragments of LYS at the same pH value. 相似文献
44.
45.
Joanna Jaskowiak Jolanta Kwasniewska Miriam Szurman-Zubrzycka Magdalena Rojek-Jelonek Paul B. Larsen Iwona Szarejko 《International journal of molecular sciences》2020,21(22)
ATR, a DNA damage signaling kinase, is required for cell cycle checkpoint regulation and detecting DNA damage caused by genotoxic factors including Al3+ ions. We analyzed the function of the HvATR gene in response to chemical clastogen-maleic acid hydrazide (MH). For this purpose, the Al-tolerant barley TILLING mutant hvatr.g was used. We described the effects of MH on the nuclear genome of hvatr.g mutant and its WT parent cv. “Sebastian”, showing that the genotoxic effect measured by TUNEL test and frequency of cells with micronuclei was much stronger in hvatr.g than in WT. MH caused a significant decrease in the mitotic activity of root cells in both genotypes, however this effect was significantly stronger in “Sebastian”. The impact of MH on the roots cell cycle, analyzed using flow cytometry, showed no differences between the mutant and WT. 相似文献
46.
Marta Semkiv Iwona Kata Orysya Ternavska Wladimir Sibirny Kostyantyn Dmytruk Andriy Sibirny 《Yeast (Chichester, England)》2019,36(5):329-339
Production of fuel ethanol is one of the possible ways to utilize crude glycerol, substantial amounts of which are produced by biodiesel industry. Earlier, we have described construction of the recombinant strains of methylotrophic thermotolerant yeast Ogataea polymorpha with simultaneous overexpression of the genes PDC1 and ADH1, which produced increased amounts of ethanol from glycerol. In this work, we have further improved these strains by overexpression of genes involved either in oxidative (through dihydroxyacetone) or phosphorylative (through glycerol-3-phosphate) pathway of glycerol catabolism, as well as heterologous gene coding for glycerol transporter FPS1 from Komagataella phaffii (formerly, Pichia pastoris). Obtained recombinant strains produced up to 10.7 g/L of ethanol (with ethanol productivity 30 mg/g of biomass/hr and yield 132 mg/g of consumed glycerol) from pure glycerol and up to 3.55 g/L of ethanol (with ethanol productivity 11.6 mg/g of biomass/hr and yield 72.3 mg/g of consumed glycerol) from crude glycerol as a carbon source, which is approximately 15 times more relative to that of the O. polymorpha wild-type strain and 2.2 more relative to the earlier constructed strain. 相似文献
47.
Tomczyk Monika Osewski Pawel Berger Marie-Helene Diduszko Ryszard Jóźwik Iwona Adamo Giorgio Pawlak Dorota A. 《Journal of Materials Science》2021,56(19):11219-11228
Journal of Materials Science - Zinc oxide (ZnO) nanostructures exhibiting high exciton binding energy and efficient radiative recombination, even at the room temperature, are of increasing interest... 相似文献
48.
Magdalena Gantner Dominika Guzek Agnieszka Najda Marta Brodowska Elżbieta Górska-Horczyczak Iwona Wojtasik-Kalinowska 《International Journal of Food Properties》2017,20(11):2527-2537
The aim of the study was to determine the effects of adding of coriander extracts to turkey meatballs. Meat samples were stored in modified atmosphere at 4°C ± 1°C for 9 days. The addition of coriander extract at 500 ppm level delayed the process of lipid oxidation for the period of 6 days of storage and growth inhibition of aerobic microorganisms for the period of 9 days of storage. The usage of a dose of 500 ppm as well as a dose of 200 ppm had no significant effect on the sensory features, but had an impact on colour parameters of the meatballs. In the groups with coriander extract, volatile terpenes were identified. 相似文献
49.
50.
Czeslaw Strumillo Ireneusz Zbici
ski Iwona Smucerowicz Clayton Crowe 《Chemical Engineering and Processing: Process Intensification》1999,38(4-6):593-600
The paper presents a theoretical and experimental analysis of a pulse combustion spray drying system. Measurements of the velocity flow field inside the drying chamber and extensive tests on drying and water evaporation were carried out for various feed rates and operating parameters of the pulse combustor. Each test included the analysis of temperature distribution in the dryer, evaporation level and sprayed material structure. LDA and PDA techniques were employed to determine the character of pulsating flow in the chamber, amount of water evaporated and to perform a profound analysis of spray structure. Experimental results show an intensive and efficient drying process. An attempt was made to perform theoretical predictions of velocity and temperature distribution in the drying chamber. The CFD technique was used to calculate time-dependent flow in the chamber. Results show vanishing velocity, pressure and temperature oscillations along the length of the drying chamber. Temperature oscillations decline faster than oscillations of pressure and velocity. Satisfactory agreement between calculations and experimental results was found in certain regions of the drying chamber. Discrepancies might be caused by simplification of the system geometry and flow pattern which were assumed to perform calculations in reasonable time. 相似文献