全文获取类型
收费全文 | 120篇 |
免费 | 2篇 |
专业分类
化学 | 96篇 |
力学 | 1篇 |
数学 | 18篇 |
物理学 | 7篇 |
出版年
2023年 | 4篇 |
2022年 | 11篇 |
2021年 | 6篇 |
2020年 | 7篇 |
2019年 | 9篇 |
2018年 | 8篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 1篇 |
2013年 | 6篇 |
2012年 | 6篇 |
2011年 | 5篇 |
2010年 | 7篇 |
2009年 | 5篇 |
2008年 | 6篇 |
2007年 | 3篇 |
2006年 | 2篇 |
2005年 | 3篇 |
2004年 | 5篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2001年 | 1篇 |
1999年 | 3篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1988年 | 1篇 |
1975年 | 1篇 |
1967年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有122条查询结果,搜索用时 15 毫秒
1.
Galina A. Selivanova Leonid M. Pokrovskii Vitaliy D. Shteingarts 《Journal of fluorine chemistry》2004,125(12):1829-1834
Chlorine-containing polyfluorinated anilines and meta-phenylenediamines undergo selective hydrodechlorination easily upon reduction by zinc in aqueous ammonia. A new approach is thus provided to synthetically valuable, partially fluorinated arylamines based on utilizing polyfluorochloroarenes, which are available as intermediates of perfluoroarene production from perchloroarenes. When chlorine atoms are present in positions both ortho and para to the amino group, para chlorine is initially eliminated. Based on this reaction, a one-pot synthesis of partially fluorinated 4-aminopyridines from 3,5-dichlorotrifluoro- and 3-chlorotetrafluoropyridine has been realized. 相似文献
2.
Geir Bjrklund Mariia Shanaida Roman Lysiuk Monica Butnariu Massimiliano Peana Ioan Sarac Oksana Strus Kateryna Smetanina Salvatore Chirumbolo 《Molecules (Basel, Switzerland)》2022,27(20)
Aging is a very complex process that is accompanied by a degenerative impairment in many of the major functions of the human body over time. This inevitable process is influenced by hereditary factors, lifestyle, and environmental influences such as xenobiotic pollution, infectious agents, UV radiation, diet-borne toxins, and so on. Many external and internal signs and symptoms are related with the aging process and senescence, including skin dryness and wrinkles, atherosclerosis, diabetes, neurodegenerative disorders, cancer, etc. Oxidative stress, a consequence of the imbalance between pro- and antioxidants, is one of the main provoking factors causing aging-related damages and concerns, due to the generation of highly reactive byproducts such as reactive oxygen and nitrogen species during the metabolism, which result in cellular damage and apoptosis. Antioxidants can prevent these processes and extend healthy longevity due to the ability to inhibit the formation of free radicals or interrupt their propagation, thereby lowering the level of oxidative stress. This review focuses on supporting the antioxidant system of the organism by balancing the diet through the consumption of the necessary amount of natural ingredients, including vitamins, minerals, polyunsaturated fatty acids (PUFA), essential amino acids, probiotics, plants’ fibers, nutritional supplements, polyphenols, some phytoextracts, and drinking water. 相似文献
3.
4.
5.
Mariia M. Efremova Anastasia I. Govdi Valeria V. Frolova Andrey M. Rumyantsev Irina A. Balova 《Molecules (Basel, Switzerland)》2021,26(9)
Cu-catalyzed 1,3-dipolar cycloaddition of methyl 2-azidoacetate to iodobuta-1,3-diynes and subsequent Suzuki-Miyaura cross-coupling were used to synthesize new triazoles derivatives: 5-aryl-4-arylethynyl-1H-1,2,3-triazoles. Investigation of their optical properties by using UV absorption and fluorescence emission spectroscopies revealed that all molecules possess fluorescence properties with the values of the Stokes shift more than 100 nm. The photophysical behavior of the two most promising triazoles in polar and non-polar solvents was also studied. 相似文献
6.
Natalia Selivanova Aidar Gubaidullin Pavel Padnya Ivan Stoikov Yuriy Galyametdinov 《Liquid crystals》2019,46(3):415-421
Supramolecular organised materials were prepared from nonionic surfactants and the following macrocyclic ionic liquids: n-tert-butylthiacalix[4]arenes containing quaternary ammonium fragments with amino acid substituents. Tetraethylene glycol monododecyl ether and decadiethylene glycol monododecyl ether were used as nonionic surfactants. They form lamellar and hexagonal mesophases in aqueous media, respectively. Liquid crystal and structural properties of these systems were studied. Intermolecular interactions of system components leading to formation of lyomesophases were estimated. Molecular structure of thiacalixarene contributes to the formation of a hydrogen bonding with surfactants. This process, in turn, initiates formation of a denser packed hexagonal structure. 相似文献
7.
Doklady Mathematics - 相似文献
8.
N. I. Afanas’ev S. B. Selyanina N. V. Selivanova 《Russian Journal of Applied Chemistry》2008,81(10):1851-1855
The influence of the initial wood species and polymolecular characteristics on the characteristics of the surface of solid-phase lignin was estimated, and the correlation of these parameters with the ability of kraft lignins to stabilize the oleic acid-water emulsion was examined. The kinetics of breakdown of emulsions stabilized with kraft lignin was studied. 相似文献
9.
Ya. I. Korenman E. I. Mel’nikova S. I. Niftaliev S. E. Boeva A. A. Selivanova E. S. Rudnichenko E. V. Bogdanova 《Russian Journal of Applied Chemistry》2009,82(8):1380-1383
System of sensors operating on the piezoquartz microweighing principle was employed to forecast the storage life of food products
based on milk serum. Signals from the sensors are integrated into an output signal forming a recognizable “visual pattern”
of an odor. 相似文献
10.
Mariia Svyntkivska Tomasz Makowski Ewa Piorkowska Marek Brzezinski Agata Herc Anna Kowalewska 《Molecules (Basel, Switzerland)》2021,26(5)
Electrospun nonwovens of poly(L-lactide) (PLLA) modified with multiwall carbon nanotubes (MWCNT) and linear ladder-like poly(silsesquioxane) with methoxycarbonyl side groups (LPSQ-COOMe) were obtained. MWCNT and LPSQ-COOMe were added to the polymer solution before the electrospinning. In addition, nonwovens of PLLA grafted to modified MWCNT were electrospun. All modified nonwovens exhibited higher tensile strength than the neat PLA nonwoven. The addition of 10 wt.% of LPSQ-COOMe and 0.1 wt.% of MWCNT to PLLA increased the tensile strength of the nonwovens 2.4 times, improving also the elongation at the maximum stress. 相似文献