全文获取类型
收费全文 | 99篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
化学 | 55篇 |
晶体学 | 1篇 |
力学 | 1篇 |
数学 | 24篇 |
物理学 | 27篇 |
出版年
2022年 | 5篇 |
2021年 | 9篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 17篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 8篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1997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 |
1948年 | 3篇 |
排序方式: 共有108条查询结果,搜索用时 15 毫秒
71.
L. A. Kochergina E. L. Ratkova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(1):34-40
The heat effects of interaction of cobalt(II) ions with D,L-threonine in aqueous solution and the corresponding heats of dilution were determined by direct calorimetry at 288.15, 298.15, and 308.15 K and ionic strength values of 0.25, 0.50, and 0.75 (against the background of potassium nitrate). The standard heat effects of formation of CoThr+, CoThr2, and CoThr 3 ? complexes were determined by extrapolation to zero ionic strength according to the equation with one individual parameter. The standard enthalpies of formation of complex particles in the hypothetical nondissociated state in aqueous solution were calculated. 相似文献
72.
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
73.
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74.
In this paper, we study the applicability of the iterative asynchronousalgorithms to systems of first order differential equations.These algorithms can be implemented on monoprocessors as wellas on multiprocessors, therefore this study extends Picard'smethod and opens a future perspective for treating differentialsystems in a parallel and asynchronous manner using multiprocessors 相似文献
75.
76.
77.
In this note, we describe the image of ?2 in Gr(2, ?4) under a morphism given by a rank two vector bundle on ?2 with Chern classes (2, 2). 相似文献
78.
E. H. EL Kinani 《International Journal of Theoretical Physics》2000,39(6):1457-1462
We review the R-deformed Heisenberg algebra and its Fock space representation.We construct the R-deformed quantum mechanics in N dimensions, and proposea new R-deformed Virasoro algebra. 相似文献
79.
80.
Nor EL Houda Tahiri Hamza Saghrouchni Noureddine Hamamouch Mostafa El Khomsi Abdulhakeem Alzahrani Ahmad Mohammad Salamatullah Lyoussi Badiaa Lalla Aicha Lrhorfi 《Molecules (Basel, Switzerland)》2022,27(23)
During the postharvest period, citrus fruits are exposed to Penicillium italicum, Penicillium digitatum, and Geotrichum candidum. Pesticides such as imazalil (IMZ), thiabendazole (TBZ), orthophenylphenol (OPP), and guazatine (GUA) are commonly used as antifungals. Glyphosate (GP) is also used in citrus fields to eliminate weed growth. The sensitivity of fungal pathogens of citrus fruit to these pesticides and 1,8-cineole was evaluated, and the effect of GP on the development of cross-resistance to other chemicals was monitored over a period of 3 weeks. IMZ most effectively inhibited the mycelial growth and spore germination of P. digitatum and P. italicum, with minimum inhibitory concentrations (MICs) of 0.01 and 0.05 mg/mL, respectively, followed by 1,8-cineole, GP, and TBZ. 1,8-Cineole and GP more effectively inhibited the mycelial growth and spore germination of G. candidum, with minimum inhibitory concentrations (MICs) of 0.2 and 1.0 mg/mL, respectively, than OPP or GUA. For the spore germination assay, all substances tested showed a total inhibitory effect. Subculturing the fungal strains in culture media containing increasing concentrations of GP induced fungal tolerance to GP as well as to the fungicides. In soil, experiments confirmed that GP induced the tolerance of P. digitatum to TBZ and GP and the tolerance of P. italicum to IMZ, TBZ, and GP. However, no tolerance was recorded against 1,8-cineole. In conclusion, it can be said that 1,8-cineole may be recommended as an alternative to conventional fungicides. In addition, these results indicate that caution should be taken when using GP in citrus fields. 相似文献