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1.
The time-resolved fluorescence properties of the bacteriophage T4 capsid protein gp23 are investigated. The structural characteristics of this protein are largely unknown and can be probed by recording time-resolved and decay-associated fluorescence spectra and intensity decay curves using a 200 ps-gated intensified CCD-camera. Spectral and decay data are recorded simultaneously, which makes data acquisition fast compared to time-correlated single-photon counting. A red-shift of the emission maximum within the first nanosecond of decay is observed, which can be explained by the different decay-associated spectra of fluorescence lifetimes of the protein in combination with dipolar relaxation. In addition, iodide quenching experiments are performed, to study the degree of exposure of the various tryptophan residues. A model for the origin of the observed lifetimes of 0.032 +/- 0.003, 0.39 +/- 0.06, 2.1 +/- 0.1 and 6.8 +/- 0.8 ns is presented: the 32 ps lifetime can be assigned to the emission of a buried tryptophan residue, the 0.4 and 2.1 ns lifetimes to two partly buried residues, and the 6.8 ns lifetime to a single tryptophan outside the bulk of the folded gp23.  相似文献   
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Abstract

The fully deprotonated anion of 1,3,5-benzene-triphosphonic acid 1,3,5-C6H3[PO32?]3 gives rise to deceptively simple 1H and 31P NMR spectra due to a corresponding [AX]3 spin system. The 13C{1H} NMR spectrum reveals two 13C isotopomers which are identified via AXX′2 systems. Results from analysis and iteration are described.  相似文献   
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Advances in wide bandgap SiC for optoelectronics   总被引:1,自引:0,他引:1  
Silicon carbide (SiC) has played a key role in power electronics thanks to its unique physical properties like wide bandgap, high breakdown field, etc. During the past decade, SiC is also becoming more and more active in optoelectronics thanks to the progress in materials growth and nanofabrication. This paper will review the advances in fluorescent SiC for white light-emitting diodes, covering the poly-crystalline doped SiC source material growth, single crystalline epitaxy growth of fluorescent SiC, and nanofabrication of SiC to enhance the extraction efficiency for fluorescent SiC based white LEDs.  相似文献   
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In examining C-6 modified 4-nitrophenyl beta-D-galactopyranosides as donor structures the beta-galactosidase (Bacillus circulans) revealed an unexpectedly broad substrate specificity which allowed successful syntheses of various disaccharide components.  相似文献   
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Background  

Mutations within the leucine-rich repeat kinase 2 (LRRK2) gene account for a significant proportion of autosomal-dominant and some late-onset sporadic Parkinson's disease. Elucidation of LRRK2 protein function in health and disease provides an opportunity for deciphering molecular pathways important in neurodegeneration. In mammals, LRRK1 and LRRK2 protein comprise a unique family encoding a GTPase domain that controls intrinsic kinase activity. The expression profiles of the murine LRRK proteins have not been fully described and insufficiently characterized antibodies have produced conflicting results in the literature.  相似文献   
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We highlight what seems to be a remaining subtlety in the argument for the cancellation of the total anomaly associated with the M5-brane in M-theory. Then, we prove that this subtlety is resolved under the hypothesis that the C-field flux is charge-quantized in the generalized cohomology theory called J-twisted cohomotopy.

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In this study a simple micro-tube-based system for analysis of metal-containing liquids is introduced and its analytical performance is evaluated. It is based on a miniaturised dielectric barrier discharge driven at atmospheric pressure. The emission lines of various elements are observed. The system is developed for quantitative measurements and the limits of detection are determined. Because of very low flow rates of just μL min−1 the approach requires extremely low sample volumes.  相似文献   
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The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe2: [(PbSe)1.14]4[NbSe2]4, [(PbSe)1.14]3[NbSe2]3[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]3[NbSe2]2[(PbSe)1.14]1[NbSe2]2, [(PbSe)1.14]2[NbSe2]3[(PbSe)1.14]2[NbSe2]1, [(PbSe)1.14]2[NbSe2]2[(PbSe)1.14]1[NbSe2]1[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]2[NbSe2]1[(PbSe)1.14]1[NbSe2]2[(PbSe)1.14]1[NbSe2]1. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance.  相似文献   
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