ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 264 (1976), S. 236-237 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Measurements were carried out from July 6 to July 10, 1976 of the vertical component of the electric field downwind of a 110-m chimney stack of a cement works at Eastgate, Co. Durham, using a series of conventional field mills1. Eastgate, 33 km W of Durham City, is sited in a broad valley, 235 m ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Ta2O5 is a candidate for use in metal–oxide–metal (MOM) capacitors in several areas of silicon device technology. Understanding and controlling leakage current is critical for successful implementation of this material. We have studied thermal and photoconductive charge transport processes in Ta2O5 MOM capacitors fabricated by anodization, reactive sputtering, and chemical vapor deposition. We find that the results from each of these three methods are similar if one compares films that have the same thickness and electrodes. Two types of leakage current are identified: (a) a transient current that charges the bulk states of the films and (b) a steady state activated process involving electron transport via a defect band. The transient process involves either tunneling conductivity into states near the Fermi energy or ion motion. The steady state process, seen most commonly in films 〈300 Å thick, is dominated by a large number of defects, ∼1019–1020 cm−3, located near the metal–oxide interfaces. The interior of thick Ta2O5 films has a substantially reduced number of defects. Modest heating (300–400 °C) of Ta2O5 in contact with a reactive metal electrode such as Al, Ti, or Ta results in interfacial reactions and the diffusion of defects across the thickness of the film. These experiments show that successful integration of Ta2O5 into semiconductor processing requires a better understanding of the impact of defects on the electrical characteristics and a better control of the metal–Ta2O5 interface. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Bulletin of economic research 24 (1972), S. 0 
    ISSN: 1467-8586
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-1472
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Unipolar air ions released into the wind constitute a tracer which can be measured with high resolution. An ion source produces a cloud with homogeneous charge density, insensitive to source strength, dependent on time since formation only. It is well suited for tracing concentration changes due to turbulence, less suited for cloud size tracing. A tight array of 8 sensors has been used to examine turbulently dispersed ions. High-resolution records are presented and discussed. The highest concentrations measured could be undiluted source material. The frequency distribution within a plume did not differ from that in a multitude of puffs. The distribution seems to be log-normal with a geometric standard deviation of about 2.45. The time resolution used corresponds to volume resolutions of 40, 225, and 650 cm3. Sample size had no apparent effect.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1573-1472
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Experiments have been carried out to investigate the dispersion of plumes at short range in the atmospheric boundary layer during stable and unstable conditions. The experiments and measurement system are described, and the results are compared with those of previous experiments. The slow meandering under stable conditions found by Mylne (1992) is not present here (probably because of topographic effects), so the plume is present on the mean centreline more often, and timescales are shorter, under stable conditions. Associated with this, statistics during stable conditions exhibit greater stability to changes in total sampling time. Intensity is found to be greater under unstable conditions, but there do not appear to be large differences in the shape of the probability density function between stable and unstable conditions. The intermittency is calculated using several variations on the conventional definition. The values obtained vary substantially according to which definition is used (although they are always higher in the stable than in the unstable experiments), demonstrating the sensitivity to both the precise definition and to measurement system characteristics. It is shown that even at very short range the mean and variance of concentration are determined almost entirely by the fluid not emanating from the source. Thus the partition between source and non-source fluid suggested by Chatwin and Sullivan (1989), while providing a more scientifically sound definition of intermittency, does not have an obvious direct practical application.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-1472
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract In July 1977 dispersion experiments with air ions as tracer were carried out at Porton in southern England. Each trial lasted about 40 min. The source height was 5 m. Continuous ion production took place in eight trials for source-sensor distances between 10 and 100m. Ion production in 1 s pulses took place in another four trials for source-sensor distances between 10 and 50 m. Two sensors were positioned at a height of 5 m and one sensor at 4 m. The experimental set-up and the weather conditions are described. Tabulated results comprise concentration frequency distributions, as well as auto- and cross-correlations, both for 0.01 and 0.1 s resolution.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1573-1987
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The momentum and turbulent kinetic energy equations are solved for a number of phenomenological closure approximations. The various methods are evaluated by comparison with several selected sets of experimental data. The empirical constants are determined such that the deviation between the experimental and theoretical values is minimized. The minimization process is carried out via a logical search algorithm which can also be applied to other problems in which the minimum or maximum value of a function of several variables is desired.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 56 (1990), S. 117-123 
    ISSN: 1570-7458
    Keywords: Rhinotermitidae ; termites ; Coptotermes formosanus ; wood density
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Les préférences alimentaires des termites xylophages ont été mesurées en comparant les différentes biomasses de bois prélevées, les pourcentages de bois consommé et l'importance des dégâts en fonction de catégories arbitrairement définies. Quand les caractéristiques des bois examinés différent, par exemple la densité, ces comparaisons ne sont plus possibles. Nous avons examiné les réactions de Coptotermes formosanus Shiraki (Iso., Rhinitermitidae) en présence de bois différant par leurs caractéristiques physiques, par compression du bois jusqu'à une densité dépassant de 40% la densité naturelle. Les termites consomment alors significativement moins en pourcentage, mais les biomasses consommées sont voisines de celles que l'on observe avec du bois du pin normal. Par contre, elles consomment significativement plus de biomasse, mais les mêmes pourcentages d'acajou compressé ou normal. Savoir quel critère doit être préférentiellement utilisé: le pourcentage ou la fraction de biomasse prélevé, dépend de la nature des facteurs de régulation de la taille du repas chez les termites. Si les termites consomment des repas de biomasse déterminée, alors la biomasse consommée est un bon critère: s'ils consomment un repas de volume déterminé, alors le pourcentage prélevé est un critère satisfaisant.
    Notes: Abstract Feeding preferences of xylophagous termites have been determined by comparing differences in wood biomass removed, percentage of wood consumed or degree of damage rated in arbitrary categories. When test woods differ in physical characteristics such as density, these measures are not comparable. We examined the response of the Formosan termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) to wood that differed in physical characteristics by compressing blocks to 40% greater than the natural density. Termites ate significantly greater percentages, but similar amounts of biomass, of uncompressed over compressed natural pine. In contrast, they ate significantly greater amounts of biomass, but similar percentages, of compressed over uncompressed mahogany. Whether percentage or amount of biomass removed should be used as a measure of preference depends on what regulates insect meal size. If termites consume meals of fixed biomass, then biomass consumed is the correct measure; percentage removed is appropriate if they consume meals of fixed volume.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2011-10-20
    Type: paper
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2016-09-07
    Type: paper
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...