Ion masking improves resolution in quadrupole mass spectrometers

Mass spectrometers analyze molecular composition by determining mass-to-charge ratio of ion fragments of molecules. Study adds significantly to quantitative understanding of quadrupole mass filter. It includes development of quantitative theory of ion oscillations, computer analysis of ion behavior, and identification of determining factors in peak tail size

Effect-specific analysis of propagation parameters

Results of propagation measurements with the satellite OLYMPUS carried out at 12.5, 20, and 30 GHz at the Research Center of the Deutsche Bundespost Telekom are discussed. In particular, attenuation, scintillation, and depolarization measurements are analyzed with special emphasis on frequency scaling of the various effects

Quadrupole ion entrance mask study

Theoretical and computer analyses of unstable ions in quadrupole mass spectrometer with ion source maskin

A User's Guide to the AI Lab: Getting Started at Tech Square

MIT Artificial Intelligence Laborator

Designing a Semantically Rich Visual Iinterface for Cultural Digital Libraries Using the UNESCO Multilingual Thesaurus

This paper reports on the design of a visual user interface for the UNESCO digital portal. The interface makes use of the UNESCO multilingual thesaurus to provide visualized views of terms and their relationships and the way in which spaces associated with the thesaurus, the query and the results can be integrated into a single user interface.\u

Designing a semantically rich visual interface for cultural digital libraries using the UNEsCO multilingual thesaurus

This paper reports on the design of a visual user interface for the UNESCO digital portal. The interface makes use of the UNESCO multilingual thesaurus to provide visualized views of terms and their relationships and the way in which spaces associated with the thesaurus, the query and the results can be integrated into a single user interface

Preparation of Neurospora crassa mitochondria

The fungus Neurospora crassa represents a eukaryotic cell with high biosynthetic activities. Cell mass doubles in 2-4 hr during expone ntial growth , even in simple salt media with sucrose as the sole carbon source. The microorgani sm forms a mycelium of long hyphae durlng vegetative growth . The mitochondria can be isolated under relatively gentle condi tions since a few breaks in the threadlike hyphae are sufficient to cause the outflow of the organelles. This article describes two methods for the physical disruption of the hyphae : (I) The cell s are opened in a grind mill between two rotating corundum di sks. This is a continuous and fast procedure and allows large- and small-scale preparations of mitochondria. (2) Hyphae are ground with sand in a mortar and pestle. This procedure can be applied to microscale preparations of mitochondria starting with minute amounts of cells. Other procedures for the isolation of Neurospora mitochondria after the physical di sruption or the enzymatic degradation of the cell wall have been described elsewher

Citation rhetoric examined

In his influential monograph «The Rhetoric of Citation Systems», Connors (1999) elaborates on the principle that scholars working with different forms of citation find themselves thinking differently, since the citation format has natural consequences in the way it interacts with the material in the practice of the writer. [...

Strategic targeting of development policies to a complex region: A GIS-based stratification applied to Uganda

It is often the case that national policies are not necessarily suitable at lower administrative levels due to the spatial complexity of natural and socio-economic resources within a country. That complexity of resources can be resolved by spatial modeling of natural and socio-economic variation. We propose a new GIS-based stratification algorithm to demarcate homogenous development domains at national level and applied that algorithm to Uganda. Based on that stratification, we assembled various spatial information to assess comparative advantages and disadvantages of these development domains for potential pathways of economic development. We expect that our stratification strategy may help policy makers and regional planners to target development investments more efficiently towards sustainable agriculture in Uganda