10,234 research outputs found
Control of equilibrium pressure-temperature conditions in cryogenic storage
Metered vent controls the pressure within a liquid hydrogen tank. Vent size is chosen to permit a gas flow which corresponds to the boil-off rate necessary to maintain the desired bulk temperature of the cryogen
The H-Coal processes: A status report
A catalytic process (H-Coal) involving the direct hydrogenation of coal to produce hydrocarbon liquids is described. Bench-scale and pilot plant development of the H-Coal process is reported. Emphasis is placed on a proposed pilot plant which will be the largest coal liquefaction plant on-line in the U.S., processing up to 600 tpd of coal. Economic considerations are given
Spin structure functions
We review the study of the internal spin structure of the proton and neutron. High-energy scattering of polarized leptons by polarized protons, neutrons, and deuterons provides a measurement of the nucleon spin structure functions. These structure functions give information on the polarized quark contributions to the spin of the proton and the neutron and allow tests of the quark-parton model and quantum chromodynamics. We discuss the formalism of deep inelastic scattering of polarized leptons on polarized nucleons, the past decade of experimental progress, and future programs to measure the polarized gluon contribution to the proton spin
Parametric, nonparametric and parametric modelling of a chaotic circuit time series
The determination of a differential equation underlying a measured time
series is a frequently arising task in nonlinear time series analysis. In the
validation of a proposed model one often faces the dilemma that it is hard to
decide whether possible discrepancies between the time series and model output
are caused by an inappropriate model or by bad estimates of parameters in a
correct type of model, or both. We propose a combination of parametric
modelling based on Bock's multiple shooting algorithm and nonparametric
modelling based on optimal transformations as a strategy to test proposed
models and if rejected suggest and test new ones. We exemplify this strategy on
an experimental time series from a chaotic circuit where we obtain an extremely
accurate reconstruction of the observed attractor.Comment: 19 pages, 8 Fig
Analysis of multi-layered films
Dye densities of multi-layered films are determined by applying a regression analysis to the spectral response of the composite transparency. The amount of dye in each layer is determined by fitting the sum of the individual dye layer densities to the measured dye densities. From this, dye content constants are calculated. Methods of calculating equivalent exposures are discussed. Equivalent exposures are a constant amount of energy over a limited band-width that will give the same dye content constants as the real incident energy. Methods of using these equivalent exposures for analysis of photographic data are presented
A rocket-borne pulse-height analyzer for energetic particle measurements
The pulse-height analyzer basically resembles a time-sharing multiplexing data-acquisition system which acquires analog data (from energetic particle spectrometers) and converts them into digital code. The PHA simultaneously acquires pulse-height information from the analog signals of the four input channels and sequentially multiplexes the digitized data to a microprocessor. The PHA together with the microprocessor form an on-board real-time data-manipulation system. The system processes data obtained during the rocket flight and reduces the amount of data to be sent back to the ground station. Consequently the data-reduction process for the rocket experiments is speeded up. By using a time-sharing technique, the throughput rate of the microprocessor is increased. Moreover, data from several particle spectrometers are manipulated to share one information channel; consequently, the TM capacity is increased
Cross-Border Data Flows, the GDPR, and Data Governance
Today, cross-border data flows are an important component of international trade and an element of digital service models. However, they are impeded by restrictions on cross-border personal data transfers and data localization legislation. This Article focuses primarily on these complexities and on the impact of the new European Union (“EU”) legislation on personal data protection—the GDPR. First, this Article introduces its discussion of these flows by placing them in their economic and geopolitical setting, including a discussion of the results of a lack of international harmonization of law in the area. In this framework, rule overlap and rival standards are relevant. Once this situation is established, this Article turns to an analysis of the legal measures that have filled the gap left by the lack of international regulation and the failure to harmonize law: extraterritorial laws in the European Union (regional legislation) and the United States (state legislation); and data localization laws in China and Russia. Specific provisions restricting cross-border personal data transfers are detailed under EU legislation, as are the international agreements that have been invaluable in allowing flows between the United States and the European Union to continue—first the Safe Harbor, and now the Privacy Shield. Finally, in this context, the role of data governance is investigated, both in the context of data controllers’ accountability for the actions of other actors in global supply chains under EU law and under the Privacy Shield. Thus, this Article goes beyond the law itself, to place requirements in the context of the globalized business world of data flows, and to suggest ways that companies may improve their compliance position worldwide
GABAergic compensation in connexin36 knock-out mice evident during low-magnesium seizure-like event activity
Gap junctions within the cerebral cortex may facilitate cortical seizure formation by their ability to synchronize electrical activity. To investigate this, one option is to compare wild-type (WT) animals with those lacking the gene for connexin36 (Cx36 KO); the protein that forms neuronal gap junctions between cortical inhibitory cells. However, genetically modified knock-out animals may exhibit compensatory effects; with the risk that observed differences between WT and Cx36 KO animals could be erroneously attributed to Cx36 gap junction effects. In this study we investigated the effect of GABAA-receptor modulation (augmentation with 16 μM etomidate and blockade with 100 μM picrotoxin) on low-magnesium seizure-like events (SLEs) in mouse cortical slices. In WT slices, picrotoxin enhanced both the amplitude (49% increase, p = 0.0006) and frequency (37% increase, p = 0.005) of SLEs; etomidate also enhanced SLE amplitude (18% increase, p = 0.003) but reduced event frequency (25% decrease, p < 0.0001). In Cx36 KO slices, the frequency effects of etomidate and picrotoxin were preserved, but the amplitude responses were abolished. Pre-treatment with the gap junction blocker mefloquin in WT slices did not significantly alter the drug responses, indicating that the reduction in amplitude seen in the Cx36 KO mice was not primarily mediated by their lack of interneuronal gap junctions, but was rather due to pre-existing compensatory changes in these animals. Conclusions from studies comparing seizure characteristics between WT and Cx36 KO mice must be viewed with a degree of caution because of the possible confounding effect of compensatory neurophysiological changes in the genetically modified animals
Microanalytical and Micromorphological Investigations of High Temperature Materials With and Without Protective Coatings
The phenomenon High Temperature Corrosion (HTC) is described; three different types (pure oxidation, high temperature hot corrosion, low temperature hot corrosion) are defined. HTC is demonstrated taking gas turbine blades as an example. The results of laboratory HTC tests under defined conditions were compared with those of long time engine experience; the agreement is very satisfactory.
Metallurgical investigations with scanning electron microscopy and EDX-/WDX-analytical techniques gave explanations for the behaviour of protective coatings . The corrosion mechanism of a NiCrAlY-plasma spray coating is explained as consequence of Cr- and Al-oxidation. A special analytical technique - the integral layer profile analysis is introduced to ameliorate concentration profile methods. By examining IN 738 LC specimen with CoCrAlY-plasma spray coating, stressed by hot gas at 900°C, the limits of this system are shown.
The aim of the present work is to demonstrate how the analytical techniques mentioned can contribute to the selection of materials and protective coatings leading to higher rentability, higher output and durability of the plant
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