Recent Advances in Algorithm Development to Extract Information from AVHRR Data

Recent Advances in High Dispersion Spectroscopy of Globular Cluster Stars

Symposium - International Astronomical Union ◽

10.1017/s0074180900035610 ◽

1988 ◽

Vol 132 ◽

pp. 525-530

Author(s):

Raffaele G. Gratton

Keyword(s):

Globular Cluster ◽

Globular Clusters ◽

High Dispersion ◽

Photographic Material ◽

Recent Advances ◽

Metal Abundances ◽

Ccd Detectors ◽

Major Progress

The use CCD detectors has allowed a major progress in abundance derivations for globular cluster stars in the last years. Abundances deduced from high dispersion spectra now correlates well with other abundance indicators. I discuss some problems concerning the derivation of accurate metal abundances for globular clusters using high dispersion spectra from both the old photographic and the most recent CCD data. The discrepant low abundances found by Cohen (1980), from photographic material for M71 giants, are found to be due to the use of too high microturbulences.

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Coherent electron nanodiffraction from clean silver nano particles in a UHV STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015112x ◽

1993 ◽

Vol 51 ◽

pp. 1058-1059

Author(s):

J. Liu ◽

M. Pan ◽

G. E. Spinnler

Keyword(s):

Supported Catalysts ◽

Imaging Techniques ◽

Nano Particles ◽

Metal Particles ◽

Shape Structure ◽

Dynamical Simulations ◽

Small Metal Particles ◽

Extract Information

Small metal particles have peculiar chemical and physical properties as compared to bulk materials. They are especially important in catalysis since metal particles are common constituents of supported catalysts. The structural characterization of small particles is of primary importance for the understanding of structure-catalytic activity relationships. The shape and size of metal particles larger than approximately 5 nm in diameter can be determined by several imaging techniques. It is difficult, however, to deduce the shape of smaller metal particles. Coherent electron nanodiffraction (CEND) patterns from nano particles contain information about the particle size, shape, structure and defects etc. As part of an on-going program of STEM characterization of supported catalysts we report some preliminary results of CEND study of Ag nano particles, deposited in situ in a UHV STEM instrument, and compare the experimental results with full dynamical simulations in order to extract information about the shape of Ag nano particles.

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The Contribution of Phonon-Scattered Electrons to High-Resolution Electron Micrographs of Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100179063 ◽

1990 ◽

Vol 48 (1) ◽

pp. 62-63

Author(s):

H. Kohl

Keyword(s):

High Resolution ◽

Spherical Aberration ◽

High Resolution Electron Microscopy ◽

Static Potential ◽

Qualitative Comparison ◽

The Past ◽

Resolution Electron ◽

High Resolution Images ◽

High Resolution Electron Micrographs ◽

Extract Information

High-Resolution Electron Microscopy is able to determine structures of crystals and interfaces with a spatial resolution of somewhat less than 2 Å. As the image is strongly dependent on instrumental parameters, notably the defocus and the spherical aberration, the interpretation of micrographs necessitates a comparison with calculated images. Whereas one has often been content with a qualitative comparison of theory with experiment in the past, one is currently striving for quantitative procedures to extract information from the images [1,2]. For the calculations one starts by assuming a static potential, thus neglecting inelastic scattering processes.We shall confine the discussion to periodic specimens. All electrons, which have only been elastically scattered, are confined to very few directions, the Bragg spots. In-elastically scattered electrons, however, can be found in any direction. Therefore the influence of inelastic processes on the elastically (= Bragg) scattered electrons can be described as an attenuation [3]. For the calculation of high-resolution images this procedure would be correct only if we had an imaging energy filter capable of removing all phonon-scattered electrons. This is not realizable in practice. We are therefore forced to include the contribution of the phonon-scattered electrons.

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Chelation-assisted transition metal-catalysed C–H chalcogenylations

Organic Chemistry Frontiers ◽

10.1039/c9qo01497g ◽

2020 ◽

Vol 7 (8) ◽

pp. 1022-1060 ◽

Cited By ~ 7

Author(s):

Wenbo Ma ◽

Nikolaos Kaplaneris ◽

Xinyue Fang ◽

Linghui Gu ◽

Ruhuai Mei ◽

...

Keyword(s):

Transition Metal ◽

Recent Advances ◽

Site Selectivity ◽

Transition Metal Catalyzed ◽

Metal Catalyzed

This review summarizes recent advances in C–S and C–Se formations via transition metal-catalyzed C–H functionalization utilizing directing groups to control the site-selectivity.

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Nucleosome dynamics

Biochemical Society Symposium ◽

10.1042/bss0730109 ◽

2006 ◽

Vol 73 ◽

pp. 109-119 ◽

Cited By ~ 2

Author(s):

Chris Stockdale ◽

Michael Bruno ◽

Helder Ferreira ◽

Elisa Garcia-Wilson ◽

Nicola Wiechens ◽

...

Keyword(s):

High Resolution ◽

Chromatin Structure ◽

Current Knowledge ◽

Dynamic Properties ◽

Structure And Dynamics ◽

Nucleosome Dynamics ◽

Sharp Focus ◽

Recent Advances ◽

Insight Into ◽

Chromatin Structure And Dynamics

In the 30 years since the discovery of the nucleosome, our picture of it has come into sharp focus. The recent high-resolution structures have provided a wealth of insight into the function of the nucleosome, but they are inherently static. Our current knowledge of how nucleosomes can be reconfigured dynamically is at a much earlier stage. Here, recent advances in the understanding of chromatin structure and dynamics are highlighted. The ways in which different modes of nucleosome reconfiguration are likely to influence each other are discussed, and some of the factors likely to regulate the dynamic properties of nucleosomes are considered.

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The Use of Real-Time Visual Displays of Speech in the Training of a Profoundly Deaf, Nonspeaking Child: A Case Report

Journal of Speech and Hearing Disorders ◽

10.1044/jshd.3603.397 ◽

1971 ◽

Vol 36 (3) ◽

pp. 397-409 ◽

Cited By ~ 10

Author(s):

Rachel E. Stark

Keyword(s):

Case Report ◽

Real Time ◽

Speech Production ◽

Behavior Problem ◽

Deaf Children ◽

Developmental Sequence ◽

Visual Displays ◽

Individual Instruction ◽

Academic Record ◽

Extract Information

Real-time amplitude contour and spectral displays were used in teaching speech production skills to a profoundly deaf, nonspeaking boy. This child had a visual attention problem, a behavior problem, and a poor academic record. In individual instruction, he was first taught to produce features of speech, for example, friction, nasal, and stop, which are present in vocalizations of 6- to 9-month-old infants, and then to combine these features in syllables and words. He made progress in speech, although sign language and finger spelling were taught at the same time. Speech production skills were retained after instruction was terminated. The results suggest that deaf children are able to extract information about the features of speech from visual displays, and that a developmental sequence should be followed as far as possible in teaching speech production skills to them.

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