نتایج جستجو برای: raman spectra

تعداد نتایج: 138355  

2006
Nikolai Gaponik Yury P Rakovich Matthias Gerlach John F Donegan Diana Savateeva Andrey L Rogach

We have studied the photoluminescence and Raman spectra of a system consisting of a polystyrene latex microsphere coated by CdTe colloidal quantum dots. The cavity-induced enhancement of the Raman scattering allows the observation of Raman spectra from only a monolayer of CdTe quantum dots. Periodic structure with very narrow peaks in the photoluminescence spectra of a single microsphere was de...

1999
T. P. Devereaux A. P. Kampf

A theory of electronic Raman scattering in nearly antiferromagnetic Fermi liquids is constructed using the phenomenological electron-electron interaction introduced by Millis, Monien, and Pines. The role of ‘‘hot spots’’ and their resulting signatures in the channel dependent Raman spectra is highlighted, and different scaling regimes are addressed. The effects of self-consistency and vertex co...

Journal: :Analytica chimica acta 1975
C W Tsai M D Morris

The resonance Raman effect has been known for many years’. Its potential for trace analysis was pointed out by Brandmiiller2 in 1959. However, full exploitation of resonance Raman spectrometry did not begin until the development of high power, multiline gas lasers as Raman excitation sources. The recent application of tunable dye lasers as excitation sources3 promises even broader applications ...

2006
M. Castanys Marta Castillejo

This work offers an automatic identification system of Raman spectra of artistic pigments. The proposed methodology is based on a fuzzy logic system, and uses principal component analysis to reduce redundancies in data and the correlation operator as an index of similarity between two Raman spectra. Moreover, as sometimes pigments are used in mixtures by artist, the designed system is able to r...

2007
Xi Wang Ali Shakouri Bin Yu Xuhui Sun Meyya Meyyappan

The observation of pure phonon confinement effect in germanium nanowires is limited due to the illumination sensitivity of Raman spectra. In this paper we measured Raman spectra for different size germanium nanowires with different excitation laser powers and wavelengths. By eliminating the local heating effect, the phonon confinement effect for small size nanowires was clearly identified. We h...

Journal: :Applied spectroscopy 2012
Kerstin Ramser Evgenya Malinina Stefan Candefjord

The aim of this study was to investigate the medial preoptic nucleus (MPN) of the anterior hypothalamus by resonance Raman spectroscopy (514.5 nm) to determine if it is possible to enhance the Raman scattering of hemoproteins in fresh brain tissue slices. The resonance effect was compared with near-infrared Raman spectra. Two groups of male Sprague Dawley rats were studied, one control group o...

2003
FRANKLIN D. HARDCASTLE

A new method is presented for interpreting the Raman spectra of bismuth oxides. The method relies on empirical relations between bismuth-oxygen (Bi-0) bond lengths, bond strengths, and Raman stretching frequencies. A least-squares exponential fit of crystallographically determined Bi-0 bond lengths and Raman stretching frequencies is presented along with a relation between Bi-0 bond strengths, ...

2005
Becky Palermo Brenda Kelly Brian O’Brien

Computational and spectroscopic techniques have been combined to probe local protein structure. Experimental resonance Raman spectra were obtained for small fragments of the 29 amino acid glucose regulating protein glucagon. The Raman spectra for these fragments were also simulated computationally and were used to aid in the interpretation of the experimental spectra. Glucagon was then probed w...

1997
THOMAS PETER DEVEREAUX

A theory for electronic Raman scattering in the cuprate superconductors is presented with a specific emphasis on the polarization dependence of the spectra which can infer the symmetry of the energy gap. Signatures of the effects of disorder on the low frequency and low temperature behavior of the Raman spectra for different symmetry channels provide detailed information about the magnitude and...

Journal: :Physical review letters 2012
Masahiro Sato Hosho Katsura Naoto Nagaosa

We study theoretically the Raman-scattering spectra in the one-dimensional (1D) quantum spin-1/2 antiferromagnets. The analysis reveals that their low-energy dynamics is exquisitely sensitive to various perturbations to the Heisenberg chain with nearest-neighbor exchange interactions, such as magnetic anisotropy, longer-range exchange interactions, and bond dimerization. These weak interactions...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید