全文获取类型
收费全文 | 154篇 |
免费 | 2篇 |
专业分类
化学 | 70篇 |
力学 | 2篇 |
数学 | 10篇 |
物理学 | 74篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2017年 | 1篇 |
2015年 | 3篇 |
2014年 | 3篇 |
2013年 | 7篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 6篇 |
2007年 | 3篇 |
2006年 | 5篇 |
2005年 | 4篇 |
2004年 | 5篇 |
2003年 | 1篇 |
2001年 | 6篇 |
2000年 | 11篇 |
1999年 | 9篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 9篇 |
1995年 | 6篇 |
1994年 | 11篇 |
1993年 | 8篇 |
1992年 | 4篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1977年 | 2篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有156条查询结果,搜索用时 15 毫秒
121.
122.
Franco Vairoletti Margot Paulino Graciela Mahler Gustavo Salinas Cecilia Saiz 《Molecules (Basel, Switzerland)》2022,27(9)
A recent screen of 67,012 compounds identified a new family of compounds with excellent nematicidal activity: the ortho-substituted benzamide families Wact-11 and Wact-12. These compounds are active against Caenorhabditis elegans and parasitic nematodes by selectively inhibiting nematode complex II, and they display low toxicity in mammalian cells and vertebrate organisms. Although a big number of benzamides were tested against C. elegans in high-throughput screens, bioisosteres of the amide moiety were not represented in the chemical space examined. We thus identified an opportunity for the design, synthesis and evaluation of novel compounds, using bioisosteric replacements of the amide group present in benzamides. The compound Wact-11 was used as the reference scaffold to prepare a set of bioisosteres to be evaluated against C. elegans. Eight types of amide replacement were selected, including ester, thioamide, selenoamide, sulfonamide, alkyl thio- and oxo-amides, urea and triazole. The results allowed us to perform a structure–activity relationship, highlighting the relevance of the amide group for nematicide activity. Experimental evidence was complemented with in silico structural studies over a C. elegans complex II model as a molecular target of benzamides. Importantly, compound Wact-11 was active against the flatworm Echinococcus granulosus, suggesting a previously unreported pan-anthelmintic potential for benzamides. 相似文献
123.
Olga Martín Francisco Mendicuti Enrique Saiz Wayne L. Mattice 《Journal of Polymer Science.Polymer Physics》1999,37(3):253-266
Steady‐state fluorescence was used to measure the ratio of emission intensities, denoted ID/IM, for excited state complexes and excited monomers of five trichromophoric compounds, 2‐naphthyl‐COO‐(CH2)m‐OOC‐2,6‐dinaphthyl‐COO‐(CH2)m‐OOC‐2‐naphthyl, m = 2–6. The linear aliphatic alcohols H(CH2)nOH, n = 1–7, as well as mixtures of ethylene glycol and methanol, were used to change the viscosity of the medium, η. The values of ID/IM depend on η and m. A Rotational Isomeric State model and Molecular Dynamics simulations were used for interpretation of the experimental results. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 253–266, 1999 相似文献
124.
Braulio García-Cámara José María Saiz Francisco González Fernando Moreno 《Optics Communications》2010,283(3):490-730
Nanostructured metamaterials offer new and interesting possibilities in nanophotonics because of the unusual optical properties they possess in the optical frequency domain. Kerker et al. [27] were pioneers in studying particles with a wide range of optical constants. They considered conditions for which the light scattering in the forward and backward directions could be zero for dipole-like particles. In this work, we have analyzed the behaviour of these two conditions when the particles have a finite-size in the nanometric range. In addition, we consider similar conditions for other scattering directions. Such conditions can be useful for designing light guides for optical communications or biomedical treatments. 相似文献
125.
de Farias RF de Souza JM de Melo JV Airoldi C 《Journal of colloid and interface science》2000,227(1):147-151
Polyaniline deposited on As(2)O(3) surface resulted in a new material, which was characterized by infrared spectoscopy, thermogravimetry, differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, and cyclic voltammetry. The mass percentage of polymer deposited on oxide surface is approximately 13%. The scanning electron microscopy images as well as the X-ray diffraction patterns provided conclusive evidence that the oxide surface is coated by the polymer. The cyclic voltammograms of the polyaniline adsorbed on As(2)O(3) surface showed that the adsorbate exerts remarkable effects on redox processes on this oxide. The pure oxide exhibited two oxidation/reduction peaks at 0.25/-0.06 and 0.47/-0.25 V attributed tentatively to the processes As(2)O(3)(s)+6H(+)+6e(-)=2As(s)+3H(2)O and As(s)+3H(+)+3e(-)=AsH(3)(g), respectively. The polyaniline-coated sample exhibited a better-defined voltammogram in which the first oxidation peak of the oxide had its intensity increased about four times. Copyright 2000 Academic Press. 相似文献
126.
Jos L. de la Pea Jos M. Saiz Pedro J. Valle Francisco Gonzlez Fernando F. Moreno 《Particle & Particle Systems Characterization》1999,16(3):113-118
We have developed an experimental light-scattering method to size metallic spherical and cylindrical particles on flat substrates. Based on the analysis of the angular positions of the minima in the light scattering patterns, we propose three different procedures. The results have been experimentally verified for both types of particle. A selection criterion for finding suitable minima is also presented. 相似文献
127.
128.
129.
We investigate the effect of specific conformations of double-bond segments in highly polyunsaturated acyl chains on the deuterium (2)H NMR order parameters of a fully hydrated 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (SDPC, 18:0/22:6 PC) lipid bilayer. The system is analyzed by performing a molecular dynamics simulation study at ambient conditions in the fluid lamellar phase. By separately calculating the different partial contributions to the total order parameter profiles measurable experimentally, we are able to get insights into the molecular origin of earlier experimental and theoretical observations. The effect of the position of the different conformations of double-bond segments along the polyunsaturated acyl chain is also examined. As in experiments performed in a series of lipid bilayers with an increasing number of cis double bonds per lipid molecule [Holte, L. L., et al. Biophys. J. 1995, 68, 2396], we find that unsaturations influence mainly the order of the bottom half of the saturated chain. Specific conformations of the polyunsaturated chain close to the lipid headgroups have a distinct effect on the order of the bottom half of the saturated chain and on the top half of the polyunsaturated chain. Our results indicate that for SDPC the conformation of the region of the polyunsaturated chain located between the first three cis double bonds is responsible for the major effects on the orientational order of both the saturated and the polyunsaturated chains. 相似文献
130.