全文获取类型
收费全文 | 121篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
化学 | 73篇 |
晶体学 | 1篇 |
力学 | 1篇 |
数学 | 27篇 |
物理学 | 28篇 |
出版年
2022年 | 3篇 |
2021年 | 9篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 17篇 |
2012年 | 3篇 |
2011年 | 4篇 |
2010年 | 5篇 |
2009年 | 5篇 |
2008年 | 7篇 |
2007年 | 7篇 |
2006年 | 1篇 |
2005年 | 4篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 7篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1968年 | 1篇 |
1948年 | 3篇 |
排序方式: 共有130条查询结果,搜索用时 31 毫秒
91.
Christopher A Reid Brendan EL Adams Damian Myers Terence J O'Brien David A Williams 《BMC neuroscience》2008,9(1):59
Background
Excitotoxicity occurs in a number of pathogenic states including stroke and epilepsy. The adaptations of neuronal circuits in response to such insults may be expected to play an underlying role in pathogenesis. Synchronous neuronal firing can be induced in isolated hippocampal slices and involves all regions of this structure, thereby providing a measure of circuit activity. The effect of an excitotoxic insult (kainic acid, KA) on Mg2+-free-induced synchronized neuronal firing was tested in organotypic hippocampal culture by measuring extracellular field activity in CA1 and CA3. 相似文献92.
D. V. Vokhmyanina E. E. Karyakina E. A. Andreev A. A. Karyakin 《Moscow University Chemistry Bulletin》2018,73(5):216-222
A planar multibiosensor for the simultaneous determination of glucose and lactate is developed by combining the Prussian Blue-based electrocatalyst and the protocol for immobilization of glucose oxidase and lactate oxidase enzymes from solutions with a high content of an organic solvent. High sensitivity coefficients (>80 mA M–1 cm–2 for lactate and >20 mA M –1 cm–2 for glucose) are demonstrated by the multibiosensors operating in the flow-injection mode in a thin-layer measuring cell. The linear range of the analyzed concentration is 1–500 μM for lactate and 5–1000 μM for glucose. A multibiosensor can be used repeatedly (the exhibited operational stability is not less than 100 measurements without the need for recalibration), which allows using it for the analysis of diluted blood samples and blood serum. The electrocatalytic system with a multibiosensor demonstrates performance characteristics that are superior to the commercial analyzers. 相似文献
93.
Lukachova LV Karyakin AA Ivanova YN Karyakina EE Varfolomeyev SD 《The Analyst》1998,123(10):1981-1985
The formation of Nafion membranes containing glucose oxidase and dimethylferrocene as a mediator was optimized using a previously reported non-aqueous enzymology approach for biosensor development. Enzyme immobilization in Nafion membranes was carried out from water-organic mixtures with a high content of organic solvent. The mediator based reagentless glucose electrode was tested in a flow injection system. The response towards glucose addition was stable: the reproducibility during 50 assays exceeded 95%. The response was linear over the glucose concentration range 0.5-50 mM. 相似文献
94.
Lilia V Lukachova Elena A Kotel'nikova Daniele D'Ottavi Egor A Shkerin Elena E Karyakina Danila Moscone Giuseppe Palleschi Antonella Curulli Arkady A Karyakin 《Bioelectrochemistry (Amsterdam, Netherlands)》2002,55(1-2):145-148
Electropolymerisation of nonconducting polymer, poly-(1,2-diaminobenzene) on the top of Prussian Blue (PB) modified electrode led to significant improvement of resulting hydrogen peroxide transducer selectivity and operational stability. The reported transducer retained 100% of response during 20 h under the continuous flow of 0.1 mM H(2)O(2), and thus improves the stability level in selective peroxide detection by one order of magnitude. The selectivity value of the PB-poly(1,2-DAB) based H(2)O(2) sensor in relation to ascorbate is approximately 600. No signals to acetaminophen and urate were investigated. PB-poly(1,2-diaminobenzene) modified electrode allows the detection of H(2)O(2) in the flow-injection mode down to 10(-7) M with the sensitivity 0.3 A M(-1) cm(-2), which is only two times lower compared to the uncovered PB based transducer. 相似文献
95.
Morozov S. V. Karyakina E. E. Zadvornyi O. A. Zorin N. A. Varfolomeev S. D. Karyakin A. A. 《Russian Journal of Electrochemistry》2002,38(1):97-102
Application of various carbon materials as substrates for immobilizing hydrogenase and creating a hydrogen enzyme electrode is studied. A stable, highly-active electrocatalyst for mediatorless oxidation–evolution of hydrogen is obtained. The electrocatalyst uses hydrogenase from Th. roseopersicina immobilized on an inactive carbon material (based on carbon cloth TVSh-300M) and retains more than 50% of its initial activity after a half year in storage. An equilibrium hydrogen potential is established on enzyme electrodes made of a graphitized cloth and graphite rods with hydrogenase immobilized on them. 相似文献
96.
A N Ivanov L V Lukachova G A Evtugyn E E Karyakina S G Kiseleva H C Budnikov A V Orlov G P Karpacheva A A Karyakin 《Bioelectrochemistry (Amsterdam, Netherlands)》2002,55(1-2):75-77
Cholinesterase sensors based on glassy carbon and planar epoxy graphite electrodes modified with processed polyaniline have been developed and examined for pesticide detection. The modification of electrode surface with polyaniline provides high operational stability and sensitivity towards the pesticides investigated. The detection limits found (coumaphos, 0.002, trichlorfon, 0.04, aldicarb, 0.03, methiocarb, 0.08 mg l(-1)) make it possible to detect the pollutants in the waters on the level of limited threshold levels without sample preconcentration. 相似文献
97.
A. V. Budruev L. N. Karyakina O. P. Levina A. V. Oleinik 《Russian Journal of Coordination Chemistry》2005,31(3):181-184
An aqua complex of copper(II) o-azidobenzoate, [Cu(OH)ABA2H2O]2 (ABA is o-azidobenzoic acid), was synthesized in an aqueous solution and identified by IR and electronic absorption spectroscopy. In the complex, the azido group is not coordinated by Cu2+. When dissolved in dry organic solvents (DMF, DMSO, dioxane, and methanol), the complex undergoes dehydration to give a chelate complex (CC) containing the Cu2+-coordinated azido group as a result of the electron density redistribution at its N atoms. The IR spectrum of the chelate complex contains no absorption band at 2135 cm–1 corresponding to the stretching vibrations of the azido group. The resulting CC is unstable in solutions and spontaneously decomposes with a release of molecular nitrogen. The interaction of a Cu2+ ion with o-azidobenzoic acid in dry organic solvents affords a CC similar to the complex obtained on the dissolution of [Cu(OH)ABA2H2O]2 in dry solvents.Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 3, 2005, pp. 195–198.Original Russian Text Copyright © 2005 by Budruev, Karyakina, Levina, Oleinik.This revised version was published online in April 2005 with a corrected cover date.This revised version was published online in April 2005 with a corrected cover date. 相似文献
98.
Photolysis of m-azidophenol (m-AP) in organic solvents and water-organic mixtures of various composition was studied using the methods of electronic spectroscopy. m-Azidophenol dissolved in water-organic mixtures was shown to form associates with solvent molecules, depending on the composition of the mixture. The nature of m-AP photolysis products and the rate of their formation are determined by the character of m-AP solvation in water-organic mixtures. In acetonitrile solution, a polymeric product is formed via the interaction of the phenol group with the nitrene of an adjacent m-AP molecule. An increase in the mole fraction of water in a water-acetonitrile mixture leads to a decrease in the yield of the polymeric product and an increase in the yield of the hydroxylamine derivative. In water-ethanol mixtures, the hydroxylamine derivative is the main product of photolysis. 相似文献
99.
Haddou EL Ghazi Anouar Jorio Izeddine Zorkani Mohamed Ouazzani-Jamil 《Optics Communications》2008,281(12):3314-3319
Electroluminescence (EL) properties of InxGa1−xN/AlyGa1−yN/GaN/SiC diode were studied. The spectral range for which EL spectra were recorded is 1–3.5 eV. Room temperature EL was obtained for forward bias (3.18 V, 220 μA) at 446.067 nm (blue luminescence band), 606.98 nm (yellow luminescence band) and 893.84 nm (Infrared luminescence band). The EL temperature dependence shows that, BL band is mostly given by e–h recombination corresponding to indium composition equal to 0.17 ± 0.01 and 0.14 ± 0.02 obtained theoretically and experimentally, respectively. The yellow band is generally weak and absent at low temperature. The IRL band is more consistent with the DAP recombination and could be explained by the thermal activation of Mg states. The luminescence bands shift to lower energies is due probably to the larger potential fluctuations effect. 相似文献
100.